机械外文翻译中英文

英文资料Limits and TolerancesThe breakage of the machine spare parts ,generally always from the surface layer beginning of .The function of the product ,particularly its credibility and durable ,be decided by the quantity of spare parts surface layer to a large extent. Purpose that studies the machine to process the surface quantity be for control the machine process medium various craft factor to process the surface quantity influence of regulation, in order to make use of these regulations to control to process the process, end attain to improve the surface quantity, the exaltation product use the function of purpose .The machine processes the surface quantity to use the influence of the function to the machine(A) The surface quantity to bear to whet the sexual influence1.Rough degree of surface to bear to whet the sexual influenceA just process vice-of two contact surfaces of good friction, the first stage is rough only in the surface of the peak department contact ,the actual contact area is much smaller than theoretical contact area, in contact with each other the peak of the units have very great stress, to produce actual contact with the surface area of plastic deformation, deformation and peak between the Department of shear failure, causing serious wear.Parts wear may generally be divided into three stages, the initial stage of wear and tear, normal wear and tear all of a sudden intense phase of stage wear.Parts of the surface roughness of the surface wear big impact. In general the smaller the value of surface roughness, wear better. However, surface roughness value is too small, lubricants difficult to store, contact between the adhesive-prone elements, wear it to increase. Therefore, the surface roughness of a best value, the value and parts of the work related to increased work load, the initial wear increased, the best rough surface is also increased.2.Cold Working hardening the surface of the wear resistanceProcessing the Cold Work hardening the surface of the friction surface layer of metal microhardness increase, it will generally improve the wear resistance. Cold Working but not a higher degree of hardening, wear resistance for the better, because too much will lead to hardening of the Cold Working excessive loose organization ofmetal, even a crack and peeling off the surface of the metal, declined to wear resistance.(B)The surface quality of the impact of fatigue strengthMetal hand alternating loads of fatigue after the damage occurred in parts often Chilled layer below the surface and, therefore parts of the surface quality of fatigue very influential.1.Surface roughness on the impact of fatigue strengthIn alternating load, the surface roughness of the Au-site easily lead to stress concentration, a fatigue crack, the higher the value of surface roughness, surface traces of Yu Shen Wen, Wen at the end of the radius smaller, anti-fatigue damage at the end of the more capacity Worse.2.Residual stress, fatigue Cold Work hardening of the impactResidual stress on the impact of large parts fatigue. Surface layer of residual stress fatigue crack will expand and accelerate the fatigue damage the surface layer and the residual stress can prevent fatigue crack growth, delaying the formation of fatigue damage.(C)The surface quality of the corrosion resistance of the impactParts of the corrosion resistance to a large extent depends on the surface roughness. The higher the value of surface roughness, Au Valley accumulate on the more corrosive substances. Corrosion resistance of the more worse.Surface layer of residual stress will produce stress corrosion cracking, lower parts of the wear-resistance, and the residual stress is to prevent stress corrosion cracking.(D) The surface quality with qualityRough surface will affect the value of the size of the co-ordination with the surface quality. The gap with rough value will increase wear and tear, increased space, with the requirements of the destruction of nature. For Fit, the assembly part of the process of convex surface-crowded peak times, the actual reduction of the surplus and reduce the support of the connection between the strength.DimensioningThe design of a machine includes many factors other than those of determining the loads and stresses and selecting the proper materials. Before construction or manufacture can begin, it is necessary to have complete assembly and detail drawings to convey all necessary information to the shop men. The designer frequently is called upon to check the drawings before they are sent to the shop. Much experience andfamiliarity with manufacturing processes are needed before one can become conversant with all phases of production drawings.Drawings should be carefully checked to see that the dimensioning is done in a manner that will be most convenient and understandable to the production departments. It is obvious that a drawing should be made in such a way that it has one and only one interpretation. In particular, shop personnel should not be required to make trigonometric or other involved calculations before the production machines can be set up.Dimensioning is an involved subject and long experience is required for its mastery.Tolerances must be placed on the dimensions of a drawing to limit the permissible variations in size because it is impossible to manufacture a part exactly to a given dimension. Although small tolerances give higher quality work and a better operating mechanism, the cost of manufacture increases rapidly as the tolerances are reduced, as indicated by the typical curve of Fig 14.1. It is therefore important that the tolerances be specified at the largest values that the operating or functional considerations permit.Tolerances may be either unilateral or bilateral. In unilateral dimensioning, one tolerance is zero, and all the variations are given by the other tolerance. In bilateral dimensioning, a mean dimension is used which extends to the midpoint of the tolerance zone with equal plus and minus variations extending each way from this dimension.The development of production processes for large-volume manufacture at low cost has been largely dependent upon interchangeability of component parts. Thus the designer must determine both the proper tolerances for the individual parts, The manner of placing tolerances on drawings depends somewhat on the kind of product or type of manufacturing process. If the tolerance on a dimension is not specifically stated, the drawing should contain a blanket note which gives the value of the tolerance for such dimensions. However, some companies do not use blanket notes on the supposition that if each dimension is considered individually, wider tolerance than those called for in the note could probably be specified. In any event it is very important that a drawing be free from ambiguities and be subject only to a single interpretation.Dimension and ToleranceIn dimensioning a drawing, the numbers placed in the dimension lines represent dimension that are only approximate and do not represent any degree of accuracy unless so stated by the designer.To specify a degree of accuracy, it is necessary to add tolerance figures to the dimension. Tolerance is the amount of variation permitted in the part or the total variation allowed in a given dimension. A shaft might have a nominal size of 2.5 in. (63.5mm), but for practical reasons this figure could not be maintained in manufacturing without great cost. Hence, a certain tolerance would be added and , if a variation of ±0.003 in.(±0.08mm) could be permitted, the dimension would be stated 2.500±0.003(63.5±0.008mm).Dimensions given close tolerances mean that the part must fit properly with some other part. Both must be given tolerances in keeping with the allowance desired, the manufacturing processes available, and the minimum cost of production and assembly that will maximize profit. Generally speaking, the cost of a part goes up as the tolerance is decreased. If a part has several or more surfaces to be machined, the cost can be excessive when little deviation is allowed from the nominal size.Allowance, which is sometimes confused with tolerance, has an altogether different meaning.It is the minimum clearance space intended between mating parts and representsthe condition of tightest permissible fit. If a shaft, size 1.4980.0000.003+-, is to fit a hole ofsize 1.5000.0030.000+-, the minimum size hole is 1.500 and the maximum size shaft is 1.498.Thus the allowance is 0.002 and the maximum clearance is 0.008 as based on the minimum shaft size and maximum hole dimension.Tolerances may be either unilateral or bilateral. Unilateral tolerance means that any variation is made in only one direction from the nominal or basic dimension.Referring to the previous example, the hole is dimensioned 1.5000.0030.000+-, whichrepresents a unilateral tolerance. If the dimensions were given as 1.500±0.003, the tolerance would be bilateral; that is , it would vary both over and under the nominal dimension. The unilateral system permits changing the tolerance while still retaining the same allowance or type of fit. With the bilateral system, this is not possible without also changing the nominal size dimension of one or both of the two mating parts. In mass production, where mating parts must be interchangeable, unilateral tolerances are customary. To have an interference or fore fit between mating parts, the tolerances must be such as to create a zero or negative allowance.Tolerances Limits and FitsThe drawing must be a true and complete statement of the designer’s expr essed in such a way that the part is convenient to manufacture. Every dimension necessary to define the product must be stated once and repeated in different views. Dimensions relating to one particular feature, such as the position and size of hole, where possible, appear on the same view.There should be no more dimensions than are absolutely necessary, and no feature should be located by more than one dimension in any direction. It may be necessary occasionally to give an auxiliary dimension for reference, possibly for inspection. When this is so, the dimension should be enclosed in a bracket and marked for reference. Such dimensions are not governed by general tolerances.Dimensions that affect the function of the part should always be specified and not left as the sum or other dimensions. If this is not done, the total permissible variation on that dimension will form the sum or difference of the other dimensions and their tolerance, and this with result in these tolerances having to be made unnecessarily tight. The overall dimension should always appear.All dimensions must be governed by the general tolerance on the drawing unless otherwise stated. Usually, such a tolerance will be governed by the magnitude of the dimension. Specific tolerances must always be stated on dimensions affecting or interchangeability.A system of tolerances is necessary to allow for the variations in accuracy that are bound to occur during manufacture, and still provide for interchangeability and correct function of the part.A tolerance is the difference in a dimension in order to allow for unavoidable imperfections in workmanship. The tolerance range will depend on the accuracy of the manufacturing organization, the machining process and the magnitude of the dimension. The greater the tolerance range is disposed on both sides of the nominal dimension. A unilateral tolerance is one where the tolerance zone is on one side only of the nominal dimension, in which case the nominal dimension may from one of the limits.Limits are the extreme dimensions of the tolerance zone. For example, nominal dimension30mm tolerance 30.0230.000++ limits 30.02530.000Fits depend on the relationship between the tolerance zones of two mating parts,and may be broadly classified into a clearance fit with positive allowance, a transition fit where the allowance may be either positive or negative (clearance or interference) , an interference fit where the allowance is always negative.Type of Limits and FitsThe ISO system of Limits and Fits, widely used in a number of leading metric countries, is considerably more complex than the ANSI system.In this system, each part has a basic size. Each limit of part, high and sign being obtained by subtracting the basic size form the limit in question. The difference between the two limits of size of a part is called the tolerance, an absolute without sign.There are three classes of fits: 1) clearance fits, 2) transition fits ( the assembly may have either clearance or interference ), and 3) interference fits .Either a shaft-basis system or a hole-basis system may be used. For any given basic size, a range of tolerance and deviations may be specified with respect to be line of zero deviation, called the zero line. The tolerance is a function of the basic size and is designated by a number symbol, called the grade-thus the tolerance grade. The position of the tolerance with respect to the zero line also a function of the basic size-is indicated by a letter symbol(or two letter), a capital letter for holes and a lowercase letter for shafts. Thus the specification for a hole and shaft having a basic size of 45mm might be45H8/g7.Twenty standard grades of tolerance are provided, called IT 01,IT 0 ,IT 1-18, providing numerical values for each nominal diameter, in arbitrary steps up to 500mm (for example 0-3,3-6,6-10…, 400-500mm). The value of the tolerance unit, I, for grades 5-16 is=+0.0.001i DWhere i is in microns and D in millimeters.Standard shaft and hole deviations similarly are provided by sets of formulas, However, for practical, both tolerances and deviations are provided in three sets of rather complex tables. Additional tables gives the values for basic sizes above 500mm and for “Commonly Used Shafts and Holes” in two categories ---“General Purpose” and “Fine Mecbanisms and Horology”.中文翻译极限与误差机械零件的破坏，一般总是从表层开始的。

附录英文原文Industrial Robot and its system’s componentsThere are a variety of definitions of the term robot. Depending on the definition used, the number of robot installations worldwide varies widely. Numerous single purpose muchines are used in manufacturing plants that might appear to be robots. These machines are hardwired to perform a single function and can not be reprogrammed to perform a different function. Such single-purpose machines do not fit the definition for industrial robots that is becoming widely accepted. This definition was developed by the robot Institute ofAmerica:A robot is a reprogrammable muhifunctional manipulator designed to move material, parts, tools, or specialized devices through variable progranmled motions for the perfommnce of a variety of tasks.Note that this definition cxmtalns the words reprograrnmable and multifunctional. It is these two characteristics that separate the true industrial robot from the various single-purpose machines used in modern manufacturing firms. The term"reprogrammable"implies two things:The robot operates aec~)rding to a written program, and this program can be rewritten to acconlmodatc a variety of manufacturing tasks.The term"multifunctional"means that the robot can, through reprogramming and the use of different cnd-effectors, perform a number of different manufacturing tasks. Definitions written around these two critical characteristics are becoming the accepted definitions among manufacturing professionals.The fimt articulated arm came about in 1951 and was used by the U.S. Atomic Energy Commission. In 1954, the first programmable robot was designed by George Devol. It was based on two important technologies:(1) Numerical control (NC) technology.(2) Remote manipulation technology.Numerical control technology provided a foma of machine control ideally suited to robots.It allowed for the control of motion by stored programs. These programs contain data points to which the robot sequentially moves, timing signals to initiate action and to stop movement, and logic statements to allow for decision rfmking.Remote manipulation technology allowed a machine to be more than just another NC machine. It allowed such machines to become robots that can perfoml a variety of manufactuing tasks in both inaccessible an unsafe environmonts. By mering these two technologies, Devol developed the first industrial robot, an unsophistieated programmable materials handling machine.The first conunercially produced robot was developed in 1959. In 1962, the first industrial robot to be used oil a production llne was installed by General Motors Corporation. This robot was produced by Unimation. A major step forward in robot control occurred in 1973 with the development of the T-3 industrial robot by Cincinnati Milaeron. The T-3 robot was the first commercially producedindustrial robot controlled by a minicomputer.Numerical control and remote manipulation technology prompted the wide scale development and use of industrial robots. But major technological developments do not take place simply because of such new capabilities. Something must provide the impetus for taking advantage of these capabilities. In the case of industrial robots, the impetus was economies.The rapid inflation of wages experienced in the 1970s tremendously increased the personnel costs of manufacturing firms. At the same time, foreign competition became a serious problem for U. S. manufacturers. Foreign manufacturers who had under taken automation on a wide scale basis, such as those in Japan, began to gain an increasingly large share of the U.S. and world market for manufactured goods, particularly automobiles.Through a variety of automation techniques, includicg robots, Japanese manufacturers, beginning in the 1970s, were able to produce better automobiles more cheaply than nonautomated U.S. manufacturers. Consequently, in order to survive, U.S. manufacturers were forced to consider any technological developments that could help improve productivity.It became imperative to produce better produets at lower costs in order to be competitive with foreign manufacturers. Other factors such as the need to find better ways of performing dangerous marmfacturing tasks contributed to the development of industrial robots. However, the principal rationale has always been,and is still, improved productivity.One of the principal advantages of robots is that they can be used in settings that are dangerous to humans. Welding and parting are examples of applications where rotmts can be dangerous to humans. Even though robots are closely asmciated with safety in the workplace, they can, in themselves, be dangerous.Robots and robot cells must be carefully designed and configured so that they do not endanger human workers and other machines. Robot work envelops should be accurately calculated and a danger zone surroundting the envelop clearly marked off. Red flooring strips and barriers can be userd to keep human workers out of a robot’s work envelope.Eren with such precautions it is still a good idea to have an automatic shutdown system in situations where robots are used. Such a system should should have the capacity to sense the need for an automatic shutdown of operations. Fault-tolerant computers and redunant systems can be installed to ensure proper shutdown of robotics systems to ensure a safe environment.Industrial robots is the science of designing, building, and applying industrial robcts. What are robots In the late 1970s the Robotic Industries Association defined a robot as〞 a manipulator, designed to move material, parts,tools or specialized devices through variable programmed motions for the performance of a variety of tasks". Although this definition does not directly include pick and place arms as robots, teleoperamrs and remotely controlled devicesare often referred to also as robots. The International Standards Organization(ISO) has a more lengthy definition of an industrial robot:A machine formed by a mechanism including several degrees of freedom, often having tile appearanoa of one or several arms ending in a wrist capable of holding a tool or a workpiece or an inspection device. In particular, its control unit must use a memorizing device and .sometimes it can use sensing or adaptation appliances taking into account environment and circumstances. These multipurtpose machines are generally designed to carry out a repetitive function and can be adapted to other functions.The RIA and ISO definitions both stress the muLtifunctional and programmable capabilities and, therefore, exclude special-purpose "hard automation" tools and equipment typically found in high volume production. Also excluded are manual remote manipulators, which are extensions of human hands for use in, for example, sterile, hot, or radioactive environments.In Japan, the Japanese Industrial Robot Association (JIRA) classifies industrial robots by the method of input informatkm and the method of teaching:1. Manual Manipulators. Manipulators directly activated by the operator.2. Fixed-sequence Robot. Robot that once programmed for a given sequence of operations is not easily changed.3. Variable-sequence Robot. Robot that can be programmed for a given sequence of operations and can easily be changed or reprogrammed.4. Playback Robot. Robot that "memorizes" work sequences taught by a human being who physically leads the device through the intended work pattern; the robot can then create this sequence repetitively from memory.5. Numerically Controlled (NC) Robot. Robot that operatas from and is controlled by digital data, as in the form of punched tape, cards, or digital switches; operates like a NC machine.6. Intelligent Robot. Robot that uses sensory perception to evaluate its environment andcmake decisions and proceeds to operate accordingly.The first-generation of robot systems was defined for the various robots with limited computer power. Their main intelligant functions include programming by showing a sequence of manipulation steps by a human operator using a teach box. Without any sensors, these robots require a prearranged and relatively fixed factory environment and, therefore, have limited use.The second-generation of robot systems was enhanced by the addition of a computer processor. A major step in industrial robotics development was the integration of a computer with the industrial robot mechanism. This has provided real-time calculation of trajectory to smooth the motions of the end effector and integration of mine simple force and proximity sensors to obtain external signals.The main applications of second generation robots include spot and arc welding, spray painting, and some assembly.Third-generation robot systems incorporate multiple eomputer processors and multiple arms that can operate asynchronously to perform .several functions. Distributed hierarchical mmputer organization is preferred, because it can coordinate motions and interface with external sensors, other machines, and other robots and can communicate with other computers. These robots can already exhibitintelligent behavior, including knowledge-based control and learning abilities.Japan ranks as the world's top robot-producing and robot-using country, with more than 40% of the world's industrial robot installations. The reasons for this penetration are sociological-and technological factors that are unique to Japan: industrial robots brought productivity and quality gains in Japanese industry, coupled with improvements of the work enviromnent. These have perpetuated the social-demand for more robots as well as increased the expectation from this technology.Current and emerging robot applications in industry can be categorized on the complexity and requirements of the job. They range from simple, low technolngy pick-and place operations through medium technology painting, some assembly and welding operations to high technology precision assembly and inspection operations.Pick-and-place Operations The earliest applications of robots were in machine loading unloading, pick-and-place, and material transfer operations. Such robots typically were not servo controlled and worked with pneumatic or hydraulic power. The Icxad-carrying requirements were high, working in dirty or hazardous factory environments. Replacing unskilled human labor often in hazardous jobs, these robots had to be robust and low in initial and maintenance costs.Painting and Welding Operations The next level in the sophistimtion of industrial robot applications was in spray painting, and spot and arc welding. These applications complemented or replaced certain skilled human labor. Often the justification was by eliminating dangerous environmental exposures. These applications often require tracking complex trajectories such as painting surface mntours, hence mrvo controlled "articulated or spherical robot structures were used.Lead-through teaching modes became commom, and sometimes sophisticated sensors are employed to maintain process consistency. Experience has shown that when properly selected and implemented, thase robotic applications usually lead to reduced overall manufacturing costs and improved product quality compared with manual method.Assembly Operations The most advanced level of technology employing third-generation industrial robots is found in assembly. System repeatability is of utmost importance. End-of-arm tooling must be compliant, i.e., have both force and displacement control to adjust part insertions, which require that the robot actually "feel" its way along. This technology usually requires a measure of artificial intelligence. Assembly robots generally are electronically driven and operate in clean enviromnents. Assembly robots are expected to exceed further technology applications.Other Applications Other typical applications of robots include inspection, quality control, and repair; processing such as laser and water jet cutting and drilling, riveting, and clean room operations; and applications in the wood, paper, and food-processing industries. As industrial robot technology and robot intelligence improve even further, additional applications may be justified effectively.The components of a robot system could be discussed either from a physical point of view or from a systems point of view. Physically, we would divide the system into the robot, power system, and controller (computer). Likewise, the robot itself could be partitioned anthropomorphically into base, shoulder, elbow, wrist, gripper, and tool. Most of these terms require little explanation.Consequently, we will describe the components of a robot system from the point of view of information transfer. That is, what infomtation or signal enters the component; what logical or arithmetic operation does the component perform; and what information or signal does the component produce It is important to note that the same physical component may perform many different information proees.sirkg operations (e. g. , a central computerperforms many different calculations on different data). Likewise, two physically separate components may perform identical information operations ( e. g., the shoulder and elbow actuators both convert signals to motion in very similar ways).Actuator Asmciated with each joint on the robot is an actuator which causes that joint to move. Typical actuators are electric motors and hydraulic cylinders. Typically, a robot system will contain six actuators, since six are required for full control of position and orientation. Many robot applications do not require this full flexibility, and consequently, robots are often built with five or fewer actuators.Sensor To control an actuator, the computer must have infommtion regarding the position and possibly the velocity of the actuator. In this context, the term position refers to a displacement from some arbitrary zero reference point for that actuator. For example, in the case of a rotary actuator , "position" would really the angular position and be measured in radians.Many types of sensors can provide indications of position and velocity. The various types of sensors require different mechanisms for interfacing to the computer. In addition, the industrial use of the manipulator requires that the interface be protected from the harsh electrical environment of the factory. Sources of electrical noise such as arc welders and large motors can easily makena digital system useless unless care is taken in design and construction of the interface.Computation We could easily have labeled the computation module "computer,"as most of the Functions to be described are typically perfommd by digital computers. However, many of the Functions may be performed in dedicated custom hardware or networks of computers We will, thus, discuss the commputational component as if it were a simple computer, recognizing that tile need for real-time control may require special equipment and that some of this equipment may even be analog, although the current trend is toward fully digital systems.One further note: We will tend to avoid the use of the term microprocessor in this book and simply say computer, although many current robot manufacturers use one or more microprocessors in their systems.The computation component performs the following operations: Servo Given the current position and/or velocity of an actuator, determine the appropriate drivesignal to move that actuator toward its desired position. "This operation must be performed for eaeh actuator. Kinematics Given the current statel of the actuators (position and velocity ),determine the current state of the gripper. Conversely, given a desired state of the hand, determine the desired state for each actuator.Dynamics Given knowledge of the loads on the arm (inertia, friction, gravity, acceleration), use this information to adjust the sorvo operation to achieve better performance.Workplace Sensor Analysis Given knowledge of the task to be performed, determine appropriate robot motion commands. This nmy include analyzing a TV picture of the workplace or measuring and compensating for forces applied at the hand.In addition to these easily identified co. mponents, there are also supervisory operations such as path planning and operator interaction.中文翻译工业机器人及其系统组成有许多关于机器人这个术语的定义。

机械手臂外文文献翻译、中英文翻译、外文翻译外文出处：《Manufacturing Engineering and Technology—Machining》附件1：外文原文XXXRobot XXX decades as high-XXX branch of industrial robots. It features can be programmed to perform tasks in a variety of expectations, in both structure and performance advantages of their own people and machines, in particular, XXX the work in the field of national economy and there are broad prospects for development. With the development of industrial automation, there has been CNC machining center, it is in reducing labor intensity, XXX, the upper and lower common in CNC machining processesmaterial, usually still use XXX relay-controlled semi-automatic device. The former time-consuming and labor intensive, inefficient; XXX, require more relays, XXX, XXX interference, XXX, XXX Programmable Logic Controller PLC-controlled robot control system formaterials up and down movement is simple, circuit design is reasonable, with a strong anti-jamming capability, ensuring the system'XXX, reduced maintenance rate,and XXXmechanics, mechanics, XXX, XXX, XXX and other fields of science, is a cross-disciplinary XXX.First, an overview of industrial manipulatorRobot is a kind of positioning control can be automated and can be re-programmedto change in multi-functional machine, which has multiple degrees of freedom can beused to carry an object in order to XXX China, plastic products industry, although still a labor-intensive, XXX1Europe and the United XXX, XXX-intensive South China, East China's coastal areas, XXX, because they have to face a high turnover rate of workers, as well as for theworkers to pay work-related injuries XXX.With the rapid development of China's industrial production, especially the reformand XXX workpiece handling, steering, XXX brazing, spray gun, wrenches and other tools for processing and assembly operations since, which has more and more attracted our attention. Robot is to imitate the manual part of the action,according toa given program, track and requirements for automatic capture, XXX.In real life, you will find this a problem. In the machine shop, the processing of parts loading time is not annoying, and labor productivity is not high, the cost of production major, and sometimes man-made incidents will occur, resulting in processing wereinjured. Think about what could replace it with the processing time of a tour as long as there are a few people, and can operate 24 hours saturated human right? The answeris yes, but the robot can come to replace it.XXX can increase XXX; XXX, ensuring product quality, to achieve safe production; particularly in the high-temperature, high pressure, low temperature, low pressure, dust, explosive, XXX the normal working people. Here I would like to think of designing a robot tobe used in actual production.XXX power: pneumatic robot refersto the compressed air as power source-driven robot. With pressure-driven and other energy-driven comparison have the following advantages: 1. Air inexhaustible, used XXX, does not require recycling and disposal,do not pollute the XXX. (Concept of environmental protection) 2. Air stick is small, the pi2peline pressure loss is small (typically less than asphalt gas path pressure drop of one-thousandth), to facilitate long-distance transport. 3. Compressed air of the working pressure is low (usually 4 to 8 kg / per square centimeter), and therefore moving the material components and XXX. With the hydraulic transmission, compared to its faster action and reaction, which is one of the advantages pneumatic outstanding. 5. The air cleaner media, it will not degenerate, not easy to plug the pipeline. But there are also places where it fly in the ointment: 1. As the compressibility of air, XXX the work, XXX as the precision of the velocity and not easily controlled. 2. As the use of low atmospheric pressure, the output power can not be too large; in order to increase the output power is bound to the structure of the entire pneumatic system size increased.With pneumatic drive and compare with other energy sources drive has the following advantages:Air inexhaustible, used XXX, without recycling anddisposal, do not pollute the XXX or a small amount of leakage would not be a XXX of air is small, the pipeline pressure loss also is very small, easy long-distance transport.The lower working pressure of compressed air, XXX general, reciprocating thrust in 1 to 2 tons XXX.Compared with the hydraulic transmission, and its faster action and reaction, XXX.Clean air medium, it will not degenerate, not easy to plug the pipeline. It can be safely used in flammable, XXX.Second, XXX, mechanical handRobot in the form of a variety of forms, some relatively simple, some more complicated, but the basic form is the same as the composition of the , Usually by the implementing agencies, transmission systems, control systems and auxiliary devices compose3d.1.Implementing agenciesXXX hands, wrists, arms, pillars. Hands are crawling institutions, is used to clamp and release the workpiece, and similar to human fingers, XXXXXX used to support the arm can also be made mobile as needed.2. TransmissionXXX, hydraulic transmission, XXX.3. Control SystemManipulator control system's main role is to control the robot according to certain procedures, direction, position, speed of action, a simple mechanical hand is generallynot set up a dedicated control system, using only trip switches, relays, control valves and circuits can be achieved dynamic drive system control, so that XXX of action. Action will have to use complex programmable robot controller, the micro-computer control.Three, XXX characteristicsXXX: the first is the general machinerydoes not require manual hand. It is an independent not affiliated with a particular hostdevice. It can be programmed according to the needs of thetask to complete the operation of the provisions. It is XXX, alsohas general machinery, memory, XXX second categoryis the need to manually do it, called the operation of aircraft. It originated in the atom,military industry, first through the operation of machines to complete a particular job,XXX such as the Moon. Used in industrial manipulator also fall into this category. The third category is dedicated manipulator, the XXX auto4matic lines, to solve the machine up and down the XXX known as the "Mechanical Hand", which is the host of services, from the host-driven; exception of a few outside the XXX, XXX.Main features:First, mechanical hand (the upper and lower material robot, assembly robot, handling robot, stacking robot, help robot, vacuum handling machines, vacuum suction crane,labor-saving spreader, pneumatic balancer, etc.).Second, cantilever cranes (cantilever crane, electric chain hoist crane, air balance the hanging, etc.)Third, rail-type transport system (hanging rail, light rail, single girder cranes, double-beam crane)Four, industrial machinery, application of handXXX of the production process developed a new type of device. In recent years, as electronic technology, especially computer extensive use of robot development and production of high-tech fields has XXX, XXX, XXX.Although the robot is not as flexible as staff, but it has to the continuous duplicationof work and labor, I do not know fatigue, not afraid of danger, XXX characteristics when compared with manual large, therefore, mechanical hand has been of great importance to many sectors, and increasingly has been applied widely, forexample:(1) Machining the workpiece loading and unloading, especially in the automatic lathe, combination machine tool use is more common.(2) XXX industry, it can beused to assemble printed circuit boards, XXX industry It can be used to assemble parts and components.(3) The working conditions may be poor, monotonous, repetitive easy to sub-fatigu5XXX.(4) XXX, XXX, XXX..(5) XXX.(6), XXX and testing.Help mechanical hands: also known as the balancer, balance suspended, labor-savingspreader, manual Transfer machine is a kind of weightlessness of manual load system,a novel, time-XXX,belonging to kinds of non-standard design of series products. Customer application needs, XXX of the automatic machinery, it can be a fixed program draws﹑XXX. Application of robot can replace the peopleengaged in monotonous﹑XXX, XXX of production, instead of people in hazardous XXX, XXX personal safety. The late 20th century, 40, the United XXX experiments, the first use of radioactive material handling robot, human robot in a safe room to XXX 50 years later, XXX, for the temperatures, polluted areas, and loading and unloading to take place the work piece material, but also as an auxiliary device in automaticmachine tools, machine tools, automatic production lines and processing center applications, the completion of the upper and lower material, or From the library take place XXX operation. Robot body mainly by the hand and sports XXX with the use of hands and operation of objects of different occasions, often there are clamping﹑XXX﹑﹑XXX﹑XXX, generally 2 to 3 degrees of XXX industry, machinery manufacture, XXX some of the staff and arm motor function, a fixd procedure for the captu6re, handling objects or operating tools, automatic operation device. It can replace human labor in order to achieve the production of heavy XXX the personal safety, which is XXX, metallurgy, electronics, light industry and nuclear power sectors. Mechanical hand tools or other XXX used for additional devices, such as the automatic machines or automatic production line handling and transmission of the workpiece, XXX centers, etc. generally do not have a separate control device. Some operating devices XXX.XXX and sports XXX. Task of hand is holding the workpiece (or tool) components, according to grasping objects by shape, size,weight, material and XXX structural forms, such as clamp type,type and adsorption-based care such as holding. Sports organizations, XXX (swing), XXX the required action, to change the location of objects by grasping and posture.Robot is the automated production of a kind used in the process of crawling and moving piece features automatic device, which is XXX a new type of device. In recent years, as electronic technology, especially computer extensive use of robot development and production of high-tech fields has XXX, XXX, XXX. Robot can replace humans completed the risk of duplication ofboring work, to reduce human XXX widely, in the machinery industry, it can be used for parts assembly, work piece handling, loading and unloadingXXX component of the FMC. The machine tool equip7XXX a flexible manufacturing cell, it was adapted to small and medium volume production, you can save a huge amount of the work piece conveyor device, compact, and adaptable. When the work piece changes, flexible production system is very easy to change will help XXX, improve product quality, and better adapt to market XXX, China'XXX isa certain distance, application andindustrialization of the size of the low level of robot research and development of a direct impact on raising the level of automation in China, from the economy, XXX, the study of mechanical hand design is very meaningful.8附件1：外文资料翻译译文呆板手机械手是近几十年发展起来的一种高科技自动化生产设备。

附录英文原文N/C Machine Tool ElementN/C machine tool elements consist of dimensioning systems, controlsystems,servomechanisms and open-orclosed-loop systems. It is important to understand each elementprior to actual programming of a numerically controlled port.The term measuring system in N/C refers to the method a machine tool uses to move a partfrom a reference point to a target point. A target point may be a certain locating for drilling a hole,milling a slot, or other machine operation. The two measuring systems used on N/C machines arethe absolute and incremental. The absolute measuring system uses a fixed reference point. It ison this point that all positional information is based. In other words, all the locations to which apart will be moved must be given dimensions relating to that original fixed reference point.Figure shows an absolute measuring system with X and Y dimensions, each based on the origin.The incremental measuring system has a floating coordinating system. With the incrementalsystem, the time the part is moved. Figure 16.2 show X and Y values using an incrementalmeasuring system. Notice that with this system, each new location bases its values in X and Yfrom the preceding location. One disadvantage to this system is that any errors made will berepeated throughout the entire program, if not detected and corrected.There are two types of control systems commonly used on N/C equipment: point-to-point andcontinuous path. A point-to-point controlled N/C machine tool, sometimes referred to as apositioning control type, has the capability of moving only along a straight line. However, whentwo axes are programmed simultaneously with equal values a 45 angle will be generated.Point-to-point systems are generally found on drilling and simple milling machine where holelocation and straight milling jobs are performed. Point-to-point systems can be utilized togenetate arcs and angles by programming the machine to move in a series of small steps. Usingthis technique, however, the actual path machined is slightly different from the cutting pathspecified.Machine tools that have the capability of moving simultaneously in two or more axes areclassified as continuous-path or contouring. These machines are used for machining arcs, radii,circles, and angles of any size in two or there dimensions. Continuous-path machines aremoreexpensive than point-to-point systems and generally require a computer to aid programming when machining complex contours.N/C servomechanisms are devices used for producing accurate movement of a table or slid along an axis. Two types of servos are commonly used on N/C equipment: electric stepping motors and hydraulic motors. Stepping motor servos are frequently used on less expensive N/C equipment. These motors are generally high-torque power servos and mounted directly to a lead screw of a table or tool slide. Most stepping motors are actuated by magnetic pulses from the stator and rotor assemblies. The net result of this action is that one rotation of the motor shaft produces 200 steps. Connection the motor shaft to a 10-pitch lead screw allows 0.0005-in. movements to be made. Hydraulic servos produce a fluid pressure that flows through gears or pistons to effect shaft rotation. Mechanical motion of lead screws and slides is accomplished through various values and controls from these hydraulic motors. However, they are more expensive and noisy. Most larger N/C machines use hydraulic servos.N/C machines that use an open-loop system contain no-feedback signal to ensure that a machine axis has traveled the required distance. That is, if the input received was to move a particular table axis 1.000 in, the servo unit generally moves the table 1.000 in. There is no means for comparing the actual table movement with the input signal, howeve r, The only assurance that the table has actually moved 1.000 in. is the reliability of the servo system used.Open-loop systems are, of course, less expensive than closed-loop systems. A closed-loop system compares the actual output with the input signal and compensates for any errors. A feedback unit actually compares the amount the table has been moved with the input signal. Some feedback units used on closed-loop systems are transducers, electrical or magnetic scales, and synchros. Closed-loop systems greatly increase the reliability of N/C machines. Machining Centers Many of today’s more sophisticated lathes are called machining centers since they are capable of performing, in addition to the normal turning operations, certain milling and drilling operations. Basically, a machining center can be thought of as being a combination turret lathe and milling machine. Additional features are sometimes included by manufacturers to increase the versatility of their machines.Numerical ControlOne of the most fundamental concepts in the area of advanced manufacturing technologies is numerical control (NC). Prior to the advent of NC, all machine tools were manually operated and controlled .Among the many limitations associated with manual control machine tools, perhaps none is more prominent than the limitation of operator skills. With manual control, the quality of the product is directly related to and limited to the skills of the operator. Numerical control represents the first major step away from human control of machine tools.Numerical control means the control of machine tools and other manufacturing systems through the use of prerecorded, written symbolic instructions. Rather than operating a machine tool, an NC technician writes a program that issues operational instructions to the machine tool. For a machine tool to be numerically controlled, it must be interfaced with a device for accepting and decoding the programmed instructions, known as a reader.Numerical control was developed to overcome the limitation of human operators, and it has done so. Numerical control machines are more accurate than manually operated machines, they can produce parts more uniformly, they are faster, and the long-run tooling costs are lower. The development of NC led to the development of several other innovations in manufacturing technology:1. Electrical discharge machining.2. Laser cutting.3. Electron beam welding.Numerical control has also made machine tools more versatile than their manually operated predecessors. An NC machine tool can automatically produce a wide variety of parts, each involving an assortment of widely varied and complex machining processes. Numerical control has allowed manufacturers to undertake the production of products that would not have been feasible from an economic perspective using manually controlled machine tools and processes. Like so many advanced technologies, NC was born in the laboratories of the Massachusetts Institute of Technology. The concept of NC was developed in the early 1950s with funding provided by the U. S. Air force. In its earliest stages, NC machines were able to make straight cuts efficiently and effectively.However, curved paths were a problem because the machine tool had to be programmed to undertake a series of horizontal and vertical steps to produce a curve. The shorter is the straight lines making up the steps, the smoother is the curve. Each line segment in the steps had to be calculated.This problem led to the development in 1959 of the Automatically Programmed Too ls (APT) language. This is a special programming language for NC that uses statements similar to English language to define the part geometry, describe the cutting tool configuration, and specify the necessary motions. The development of the APT language was a major step forward in the further development of NC technology. The original NC systems were vastly different from those used today. The machines had hardwired logic circuits. The instructional programs were written on punched paper, which was later to be replaced by magnetic plastic tape. A tape reader was used to interpret the instructions written on the tape for the machine. Together, all of this represented a giant step forward in the control of machine tools. However, there were a numberof problems with NC at this point in its development.A major problem was the fragility of the punched paper tape medium. It was common for the paper tape containing the programmed instructions to break or tear during a machining process. This problem was exacerbated by the fact that each successive time a part was produced on a machine tool, the paper tape carrying the programmed instructions had to be rerun through the reader. If it was necessary to produce 100 copies of a given part, it was also necessary to run the paper tape through the reader 100 separate times. Fragile paper tapes simply could not withstand the rigors of a shop floor environment and this kind of repeated use.This led to the development of a special magnetic plastic tape. Whereas the paper tape carried the programmed instructions as a series of holes punched in the tape, the plastic tape carried the instructions as a series of holes punched in the tape, the plastic tape carried the instructions as a series of magnetic dots. The plastic tape was much stronger than the paper taps, which solved the problem of frequent tearing and breakage. However, it still left two other problems.The most important of these was that it was difficult or impossible to change the instructions entered on the tape. To make even the most minor adjustments in a program of instructions, it was necessary to interrupt machining operations and make a new tape .It was also still necessary to run the tape through the reader as many times as there were parts to be produced. Fortunately, computer technology became a reality and soon solved the problems of NC associated with punched paper and plastic tape.The development of a concept known as direct numerical control (DNC) solved the paper and plastic tape problems associated with numerical control by simply eliminating tape as the medium for carrying the programmed instructions. In direct numerical control .machine tools are tied, via a data transmission link, to a host computer. Programs for operating the machine tools are stored in the host computer and fed to the machine tool as needed via the data transmission linkage. Direct numerical control represented a major step forward over punched tape and plastic tape. However, it is subject to the same limitations as all technologies that depend on a host computer. When the lost computer goes down, the machine tools also experience downtime. This problem led to the development of computer numerical control.The development of the microprocessor allowed for the development of programmable logic controllers (PLCs) and microcomputers. These two technologies allowed for the development of computer numerical control (CNC).With CNC, each machine tool has a PLC or a microcomputer that serves the same purpose. This allows programs to be input and stored at each individual machine tool. It also allows programs to be developed off-line and downloaded at the individual machine tool. CNC solved the problems associated with downtime of the hostcomputer, but it introduced another known as data management. The same program might be loaded on ten different microcomputers with no communication among them. This problem is in the process of being solved by local area networks that connect microcomputers for better data management. Cutting Tool GeometryShape of cutting tools, particularly the angles, and tool material are very important factors. Angles determine greatly not only tool life but finish quality as well. General principles upon which cutting tool angles are based do not depend on the particular tool, Basically, the same considerations hold true whether a lathe tool, a milling cutter, a drill, or even a grinding wheel are being designed. Since, however the lathe tool, depicted in Fig. 18.1, might be easiest to visualize, its geometry is discussed.Tool features have been identified by many names. The technical literature is full of confusing terminology. Thus in the attempt to cleat up existing disorganized conceptions and nomenclature, this American Society of Mechanical Engineers published AS A Standard B5-22-1950. What follows is based on it.A single-point tool is a cutting tool having one face and one continuous cutting edge, Tool angles identified in Fig. 18.2 are as follows:Tool angle 1, on front view, is the back-rank angle. It is the angle between the tool face and a line parallel to the tool base of the shank in a longitudinal plane perpendicular to the tool base. When this angle is downward from front to rear of the cutting edge, the rake is positive; when upward from front to black, the rake is negative. This angle is most significant in the machining process, because it directly affects the cutting force, finish, and tool life.The side-rake angle, numbered 2, measures the slope of the face on a cross plane perpendicular to the tool base. It, also, is an important angle, because it directs chip flow to the side of the tool post and permits the tool to feed more easily into the work.The end-relief angle is measured between a line perpendicular to the base and the end flank immediately below the end cutting edge; it is numbered 3 in the figure. It provides clearance between work and tool so that its cut surface can flow by with minimum rubbing against the tool. To save time, a portion of the end flank of the tool may sometimes be lest unground, having been previously forged to size. In such case, this end-clearance angle, numbered 4, measured to the end flank surface below the ground portion, would be larger than the relief angle.Often the end cutting edge is oblique to the flank. The relief angle is then best measured in a plane normal to the end cutting edge angle. Relief is also expressed as viewed from side and end of the tool.The side-relief angle, indicated as 5, is measured between the side flank, just below thecutting edge, and a line through the cutting edge perpendicular to the base of the tool. This clearance permits the tool to advance more smoothly into the work.Angle 6 is the end-cutting-edge angle measured between the end cutting edge and a line perpendicular to the side of the tool shank. This angle prevents rubbing of the cut surface and permits longer tool file.The side-cutting-edge angle, numbered 7, is the angle between the side cutting edge and the side of the tool shank. The true length of cut is along this edge. Thus the angel determines the distribution of the cutting forces. The greater the angle, the longer the tool life; but the possibility of charter increases. A compromise must, as usual, be reached.The nose angle, number 8, is the angle between the two component cutting edges. If the corner is rounded off, the arc size is defined by the nose radius 9. The radius size influences finish and chatter.Sand CastingThe first stage in the production of sand castings must be the design and manufacture of a suitable pattern. Casting patterns are generally made from hard word and the pattern has to be made larger than the finished casting size to allow for the shrinkage that takes place during solidification and cooling. The extent of this shrinkage varies with the type of metal or alloy to be cast. For all but the simplest shapes the pattern will be made in two or more pieces to facilitate moulding. If a hollow casting is to be made the pattern design will include extension pieces so that spaces to accept the sand core are moulded into sand. These additional spaces in the mould are termed core prints.Sand moulds for the production of small and medium-sized castings are made in a moulding box. The mould is made in two or more parts in order that the pattern may be removed.The drag half of the mould box is placed on a flat firm board and the drag half of the pattern placed in position. Facing sand is sprinkled over the pattern and then the mould box is filled with moulding sand. The sand is rammed firmly around the pattern. This process of filling and ramming may be done by hand but mould production is automated in a large foundry with the mould boxes moving along a conveyor, firstly to be filled with sand from hoppers and then to pass under mechanical hammers for ramming. When ramming of the sand is complete, excess sand is removed to leave a smooth surface flush with the edges of the moulding box.The completed drag is now turned over and the upper, or cope, portion of the moulding box positioned over it. The cope half of the pattern is placed in position, correct alignment being ensured by means of small dowel pins. Patterns for the necessary feeder, runner and risers are also placed so as to give an even distribution of metal into the mould cavity. The rise rs should coincide with the highest readily escape from the mould. The sizes of risers should be such thatthe metal in them does not freeze too rapidly. An important function of a riser is to act as reservoir of liquid metal to feed solidification within the mould. A thin coating of dry parting sand is sprinkled into mould at this stage. This is to prevent the cope and drag sticking together when the cope half is moulded. The cope is now filled with moulding sand and this is rammed firmly into shape in the same manner as in the making of the drag.After the ramming of sand in the cope is completed the two halves of the moulding box are carefully separated. At this stage venting of the moulding box are carefully separated. At this stage venting of the mould can be done, if necessary, to increase the permeability of the mould. After venting the patterns are carefully removed from both cope and drag, and a gate or gates are carefully cut to connect the runner channel with the main cavity. Gates should be sited to allow or entry into mould with a minimum of turbulence. Any loose sand is gently blown away and if a core is to be used it the cope upon the drag and it is then ready for use. Liquid metal is poured smoothly into the mould via the feeder. Pouring ceases when liquid metal appears at the top of the risers and the feeder channel is also full.When the metal that has been poured into a sand mould has fully solidified the mould is broken and casting is removed. The casting still has the runner and risers attached to it and there will be sand adhering to portions of the surface. Runners and risers are cut off and returned to the melting furnace. Sand cores are broken and adherent sand is cleaned from the surface by vibration or by sand blasting with dry sand. Any fins or metal flash formed at mould parting lines are removed by grinding and the castings are then ready for inspection.The main Elements of Horizontal Milling MachinesColumn and base The column and base form the foundation of the complete machine. Both are made from cast iron, designed with thick sections to ensure complete rigidity and freedom form vibration. The base, upon which the column is mounted, is also the cutting-fluid reservoir and contains the pump to circulate the fluid to cutting area.The column contains the spindle, accurately located in precision bearings. The spindle id driven through a gearbox from a vee-belt drive from the electric motor housed at the base of column. The gearbox enables a range of spindle speeds to be selected. In the model shown, twelve spindle speeds from 32 to 1400rev/min are available. The front of column carries the guideways upon which the knee is located and guided in a vertical direction.KneeThe knee, mounted on the column guideways, provides the vertical movement of the table. Power feed is available, through a gearbox mounted on the side, from a separate built-in motor, providing a range of twelve feed rates from 6 to 250mm/min. Drive is through a leadscrew, whose bottom end is fixed to machine base. Provision is made to raise and lower the knee byhand through a leadscrew and nut operates by a handwheel at the front. The knee has guideways on its top surface giving full-width support to the saddle and guiding it in a transverse direction. lock is provided to clamp the knee in any vertical position on the column.SaddleThe saddle, mounted on the knee guideways, providers the transverse movement of the table. Power feed is provided through the gearbox on the knee. A range of twelve feeds is available, from 12 to 500mm/min. Alternative hand movement is provided through a leadscrew and nut by a hand heel at the front of the knee.Camping of saddle to the knee is achieved by two clamps on the side of the saddle.The saddle has dovetail gun its upper surface, at right angles to the knee guideways, to provide a guide to the table in a longitudinal direction.TableThe table provides the surface upon which all workpieces and workholding equipment are located and clamped. A series of tee slots is provided for this purpose. The dovetail guides on undersurface locate in the guideways on the saddle, giving straight-line movement to the table in longitudinal direction at right angles to the saddle movement.Power feed is provided from the knee gearbox, through the saddle, to the table leadscrew. Alternative hand feed is provided by a handwheel at each end of the table. Stops at the front of the table can be set to disengage the longitudinal feed automatically in each direction. Spindle The spindle, accurately mounted in precision bearings, provides the drive for the milling cutters. Cutters can be mounted straight on the spindle nose or in curter-holding devices which in turn are mounted in the spindle, held in position by a drawbolt passing the hold spindle. Spindles of milling machines have a standard spindle nose to allow for easy interchange of cutters and cutter-holding devices. The bore of the nose is tapered to provide accurate location, the angle of taper being 1. The diameter of the taper depends on the size of the machine and may be 30,40,or 50 IST. Due to their steepness of angle, there tapers –known as non-stick or self-releasing- cannot be relied upon to transmit the drive to the cutter or cutter-holding device. Two driving keys are provided to transmit the drive.Overarm and arbor supportDue to the length of arbors used, support is required at the outer end to prevent deflection when cutting takes place. Support is provided by an arbor-support bracket, clamped to an overarm which is mounted on top of the column in a dovetail slide. The overarm is adjustable in or out for different lengths of arbor, or can be fully pushed in when arbor support is not required. Two clamping bolts are support is located in the overarm dovetail and is locked by which the arbor runs during splindle rotation.中文译文数控机床的组成部分数控机床的组成部分包括测量系统、控制系统、伺服系统及开环或闭环系统，在对数控零件进行实际程序设计之前，了解各组成部分是重要的。

英文资料High-speed millingHigh-speed machining is an advanced manufacturing technology, different from the traditional processing methods. The spindle speed, cutting feed rate, cutting a small amount of units within the time of removal of material has increased three to six times. With high efficiency, high precision and high quality surface as the basic characteristics of the automobile industry, aerospace, mold manufacturing and instrumentation industry, such as access to a wide range of applications, has made significant economic benefits, is the contemporary importance of advanced manufacturing technology. For a long time, people die on the processing has been using a grinding or milling EDM (EDM) processing, grinding, polishing methods. Although the high hardness of the EDM machine parts, but the lower the productivity of its application is limited. With the development of high-speed processing technology, used to replace high-speed cutting, grinding and polishing process to die processing has become possible. To shorten the processing cycle, processing and reliable quality assurance, lower processing costs.1 One of the advantages of high-speed machiningHigh-speed machining as a die-efficient manufacturing, high-quality, low power consumption in an advanced manufacturing technology. In conventional machining in a series of problems has plagued by high-speed machining of the application have been resolved.1.1 Increase productivityHigh-speed cutting of the spindle speed, feed rate compared withtraditional machining, in the nature of the leap, the metal removal rate increased 30 percent to 40 percent, cutting force reduced by 30 percent, the cutting tool life increased by 70% . Hardened parts can be processed, a fixture in many parts to be completed rough, semi-finishing and fine, and all other processes, the complex can reach parts of the surface quality requirements, thus increasing the processing productivity and competitiveness of products in the market.1.2 Improve processing accuracy and surface qualityHigh-speed machines generally have high rigidity and precision, and other characteristics, processing, cutting the depth of small, fast and feed, cutting force low, the workpiece to reduce heat distortion, and high precision machining, surface roughness small. Milling will be no high-speed processing and milling marks the surface so that the parts greatly enhance the quality of the surface. Processing Aluminum when up Ra0.40.6um, pieces of steel processing at up to Ra0.2 ~ 0.4um.1.3 Cutting reduce the heatBecause the main axis milling machine high-speed rotation, cutting a shallow cutting, and feed very quickly, and the blade length of the workpiece contacts and contact time is very short, a decrease of blades and parts of the heat conduction. High-speed cutting by dry milling or oil cooked up absolute (mist) lubrication system, to avoid the traditional processing tool in contact with the workpiece and a lot of shortcomings to ensure that the tool is not high temperature under the conditions of work, extended tool life.1.4 This is conducive to processing thin-walled partsHigh-speed cutting of small cutting force, a higher degree of stability, Machinable with high-quality employees compared to the company may be very good, but other than the company's employees may Suanbu Le outstanding work performance. For our China practice, we use the models to determine the method of staff training needs are simple and effective. This study models can be an external object, it can also be a combination of internal and external. We must first clear strategy for the development of enterprises. Through the internal and external business environment and organizational resources, such as analysis, the future development of a clear business goals and operational priorities. According to the business development strategy can be compared to find the business models, through a comparative analysis of the finalization of business models. In determining business models, a, is the understanding of its development strategy, or its market share and market growth rate, or the staff of the situation, and so on, according to the companies to determine the actual situation. As enterprises in different period of development, its focus is different, which means that enterprises need to invest the manpower and financial resources the focus is different. So in a certain period of time, enterprises should accurately selected their business models compared with the departments and posts, so more practical significance, because the business models are not always good, but to compare some aspects did not have much practical significance, Furthermore This can more fully concentrate on the business use of limited resources. Identify business models, and then take the enterprise of the corresponding departments and staff with the business models for comparison, the two can be found in the performance gap, a comparative analysis to find reasons, in accordance with this business reality, the final identification of training needs. The cost of training is needed, if not through an effective way to determine whether companies need to train and the training of the way, but blind to training, such training is difficult to achieve the desired results. A comparison only difference between this model is simple and practical training.1.5 Can be part of some alternative technology, such as EDM, grinding high intensity and high hardness processingHigh-speed cutting a major feature of high-speed cutting machine has the hardness of HRC60 parts. With the use of coated carbide cutter mold processing, directly to the installation of ahardened tool steel processing forming, effectively avoid the installation of several parts of the fixture error and improve the parts of the geometric location accuracy. In the mold of traditional processing, heat treatment hardening of the workpiece required EDM, high-speed machining replace the traditional method of cutting the processing, manufacturing process possible to omit die in EDM, simplifying the processing technology and investment costs .High-speed milling in the precincts of CNC machine tools, or for processing centre, also in the installation of high-speed spindle on the general machine tools. The latter not only has the processing capacity of general machine tools, but also for high-speed milling, a decrease of investment in equipment, machine tools increased flexibility. Cutting high-speed processing can improve the efficiency, quality improvement, streamline processes, investment and machine tool investment and maintenance costs rise, but comprehensive, can significantly increase economic efficiency.2 High-speed millingHigh-speed milling the main technical high-speed cutting technology is cutting the development direction of one of it with CNC technology, microelectronic technology, new materials and new technology, such as technology development to a higher level. High-speed machine tools and high-speed tool to achieve high-speed cutting is the prerequisite and basic conditions, in high-speed machining in the performance of high-speed machine tool material of choice and there are strict requirements.2.1 High-speed milling machine in order to achieve high-speed machiningGeneral use of highly flexible high-speed CNC machine tools, machining centers, and some use a dedicated high-speed milling, drilling. At the same time a high-speed machine tool spindle system and high-speed feeding system, high stiffness of the main characteristics of high-precision targeting and high-precision interpolation functions, especially high-precision arc interpolation function. High-speed machining systems of the machine a higher demand, mainly in the following areas:General use of highly flexible high-speed CNC machine tools, machining centers, and some use a dedicated high-speed milling, drilling. At the same time a high-speed machine tool spindle system and high-speed feeding system, high stiffness of the main characteristics of high-precision targeting and high-precision interpolation functions, especially high-precision arc interpolation function. High-speed machining systems of the machine a higher demand, mainly in the following areas:High-speed milling machine must have a high-speed spindle, the spindle speed is generally 10000 ~ 100000 m / min, power greater than 15 kW. But also with rapid speed or in designated spots fast-stopping performance. The main axial space not more than 0 .0 0 0 2 m m. Often using high-speed spindle-hydrostatic bearings, air pressure-bearing, mixed ceramic bearings, magneticbearing structure of the form. Spindle cooling general use within the water or air cooled.High-speed processing machine-driven system should be able to provide 40 ~ 60 m / min of the feed rate, with good acceleration characteristics, can provide 0.4 m/s2 to 10 m/s2 acceleration and deceleration. In order to obtain good processing quality, high-speed cutting machines must have a high enough stiffness. Machine bed material used gray iron, can also add a high-damping base of concrete, to prevent cutting tool chatter affect the quality of processing. A high-speed data transfer rate, can automatically increase slowdown. Processing technology to improve the processing and cutting tool life. At present high-speed machine tool manufacturers, usually in the general machine tools on low speed, the feed of the rough and then proceed to heat treatment, the last in the high-speed machine on the half-finished and finished, in improving the accuracy and efficiency at the same time, as far as possible to reduce processing Cost.2.2 High-speed machining toolHigh-speed machining tool is the most active one of the important factors, it has a direct impact on the efficiency of processing, manufacturing costs and product processing and accuracy. Tool in high-speed processing to bear high temperature, high pressure, friction, shock and vibration, such as loading, its hardness and wear-resistance, strength and toughness, heat resistance, technology and economic performance of the basic high-speed processing performance is the key One of the factors. High-speed cutting tool technology development speed, the more applications such as diamond (PCD), cubic boron nitride (CBN), ceramic knives, carbide coating, (C) titanium nitride Carbide TIC (N) And so on. CBN has high hardness, abrasion resistance and the extremely good thermal conductivity, and iron group elements between the great inertia, in 1300 ℃ would not have happened significant role in the chemical, also has a good stability. The experiments show that with CBN cutting toolHRC35 ~ 67 hardness of hardened steel can achieve very high speed. Ceramics have good wear resistance and thermal chemical stability, its hardness, toughness below the CBN, can be used for processing hardness of HRC <5 0 parts. Carbide Tool good wear resistance, but the hardness than the low-CBN and ceramics. Coating technology used knives, cutting tools can improve hardness and cutting the rate, for cutting HRC40 ~ 50 in hardness between the workpiece. Can be used to heat-resistant alloys, titanium alloys, hightemperature alloy, cast iron, Chungang, aluminum and composite materials of high-speed cutting Cut, the most widely used. Precision machining non-ferrous metals or non-metallic materials, or the choice of polycrystalline diamond Gang-coated tool.2.3 High-speed processing technologyHigh-speed cutting technology for high-speed machining is the key. Cutting Methods misconduct, will increase wear tool to less than high-speed processing purposes. Only high-speed machine tool and not a good guide technology, high-speed machining equipment can not fullyplay its role. In high-speed machining, should be chosen with milling, when the milling cutter involvement with the workpiece chip thickness as the greatest, and then gradually decreased. High-speed machining suitable for shallow depth of cut, cutting depth of not more than 0.2 mm, to avoid the location of deviation tool to ensure that the geometric precision machining parts. Ensure that the workpiece on the cutting constant load, to get good processing quality. Cutting a single high-speed milling path-cutting mode, try not to interrupt the process and cutting tool path, reducing the involvement tool to cut the number to be relatively stable cutting process. Tool to reduce the rapid change to, in other words when the NC machine tools must cease immediately, or Jiangsu, and then implement the next step. As the machine tool acceleration restrictions, easy to cause a waste of time, and exigency stop or radical move would damage the surface accuracy. In the mold of high-speed finishing, in each Cut, cut to the workpiece, the feed should try to change the direction of a curve or arc adapter, avoid a straight line adapter to maintain the smooth process of cutting.3 Die in high-speed milling processing ofMilling as a highly efficient high-speed cutting of the new method,inMould Manufacturing has been widely used. Forging links in the regular production model, with EDM cavity to be 12 ~ 15 h, electrodes produced 2 h. Milling after the switch to high-speed, high-speed milling cutter on the hardness of HRC 6 0 hardened tool steel processing. The forging die processing only 3 h20min, improve work efficiency four to five times the processing surface roughness of Ra0.5 ~ 0.6m, fully in line with quality requirements.High-speed cutting technology is cutting technology one of the major developments, mainly used in automobile industry and die industry, particularly in the processing complex surface, the workpiece itself or knives rigid requirements of the higher processing areas, is a range of advanced processing technology The integration, high efficiency and high quality for the people respected. It not only involves high-speed processing technology, but also including high-speed processing machine tools, numerical control system, high-speed cutting tools and CAD / CAM technology. Die-processing technology has been developed in the mold of the manufacturing sector in general, and in my application and the application of the standards have yet to be improved, because of its traditional processing with unparalleled advantages, the future will continue to be an inevitable development of processing technology Direction.4 Numerical control technology and equipping development trend and countermeasureEquip the engineering level, level of determining the whole national economy of the modernized degree and modernized degree of industry, numerical control technology is it develop new developing new high-tech industry and most advanced industry to equip (such as information technology and his industry, biotechnology and his industry, aviation, spaceflight, etc. national defense industry) last technology and getting more basic most equipment. Marx has ever said "the differences of different economic times, do not lie in what is produced, and lie in how to produce,produce with some means of labor ". Manufacturing technology and equipping the most basic means of production that are that the mankind produced the activity, and numerical control technology is nowadays advanced manufacturing technology and equips the most central technology. Nowadays the manufacturing industry all around the world adopts numerical control technology extensively, in order to improve manufacturing capacity and level, improve the adaptive capacity and competitive power to the changeable market of the trends. In addition every industrially developed country in the world also classifies the technology and numerical control equipment of numerical control as the strategic materials of the country, not merely take the great measure to develop one's own numerical control technology and industry, and implement blockading and restrictive policy to our country in view of " high-grade, precision and advanced key technology of numerical control " and equipping. In a word, develop the advanced manufacturing technology taking numerical control technology as the core and already become every world developed country and accelerate economic development in a more cost-effective manner, important way to improve the overall national strength and national position. Numerical control technology is the technology controlled to mechanical movement and working course with digital information, integrated products of electromechanics that the numerical control equipment is the new technology represented by numerical control technology forms to the manufacture industry of the tradition and infiltration of the new developing manufacturing industry, namely the so-called digitization is equipped, its technological range covers a lot of fields: (1)Mechanical manufacturing technology; (2)Information processing, processing, transmission technology; (3)Automatic control technology; (4)Servo drive technology;(5)Technology of the sensor; (6)Software engineering ,etc..Development trend of a numerical control technologyThe application of numerical control technology has not only brought the revolutionary change to manufacturing industry of the tradition, make the manufacturing industry become the industrialized symbol , and with the constant development of numerical control technology and enlargement of the application, the development of some important trades (IT , automobile , light industry , medical treatment ,etc. ) to the national economy and the people's livelihood of his plays a more and more important role, because the digitization that these trades needed to equip has already been the main trend of modern development. Numerical control technology in the world at present and equipping the development trend to see, there is the following several respect [1- ] in its main research focus.5 A high-speed, high finish machining technology and new trend equippedThe efficiency, quality are subjavanufacturing technology. High-speed, high finish machining technology can raise the efficiency greatly , improve the quality and grade of the products, shorten production cycle and improve the market competitive power. Japan carries the technological research association first to classify it as one of the 5 great modern manufacturing technologies forthis, learn (CIRP) to confirm it as the centre in the 21st century and study one of the directions in international production engineering.In the field of car industry, produce one second when beat such as production of 300,000 / vehicle per year, and many variety process it is car that equip key problem that must be solved one of; In the fields of aviation and aerospace industry, spare parts of its processing are mostly the thin wall and thin muscle, rigidity is very bad, the material is aluminium or aluminium alloy, only in a situation that cut the speed and cut strength very small high, could process these muscles, walls. Adopt large-scale whole aluminium alloy method that blank " pay empty " make the wing recently, such large-scale parts as the fuselage ,etc. come to substitute a lot of parts to assemble through numerous rivet , screw and other connection way, make the intensity , rigidity and dependability of the component improved. All these, to processing and equipping the demand which has proposed high-speed, high precise and high flexibility.According to EMO2001 exhibition situation, high-speed machining center is it give speed can reach 80m/min is even high , air transport competent speed can up to 100m/min to be about to enter. A lot of automobile factories in the world at present, including Shanghai General Motors Corporation of our country, have already adopted and substituted and made the lathe up with the production line part that the high-speed machining center makes up. HyperMach lathe of U.S.A. CINCINNATI Company enters to nearly biggest 60m/min of speed, it is 100m/min to be fast, the acceleration reaches 2g, the rotational speed of the main shaft has already reached 60 000r/min. Processing a thin wall of plane parts, spend 30min only, and same part general at a high speed milling machine process and take 3h, the ordinary milling machine is being processed to need 8h; The speed and acceleration of main shaft of dual main shaft lathes of Germany DMG Company are up to 120000r/mm and 1g.In machining accuracy, the past 10 years, ordinary progression accuse of machining accuracy of lathe bring 5μm up to from 10μm already, accurate grades of machining center from 3～5μm, rise to 1～1.5μm, and ultraprecision machining accuracy is i t enter nanometer grade to begin already (0.01μm).In dependability, MTBF value of the foreign numerical control device has already reached above 6 000h, MTBF value of the servo system reaches above 30000h, demonstrate very high dependability .In order to realize high-speed, high finish machining, if the part of function related to it is electric main shaft, straight line electrical machinery get fast development, the application is expanded further .5.2 Link and process and compound to process the fast development of the lathe in 5 axesAdopt 5 axles to link the processing of the three-dimensional curved surface part, can cut with the best geometry form of the cutter , not only highly polished, but also efficiency improves by a large margin . It is generally acknowledged, the efficiency of an 5 axle gear beds can equal 2 3 axle gearbeds, is it wait for to use the cubic nitrogen boron the milling cutter of ultra hard material is milled and pared at a high speed while quenching the hard steel part, 5 axles link and process 3 constant axles to link and process and give play to higher benefit. Because such reasons as complicated that 5 axles link the numerical control system , host computer structure that but go over, it is several times higher that its price links the numerical control lathe than 3 axles , in addition the technological degree of difficulty of programming is relatively great, have restricted the development of 5 axle gear beds.At present because of electric appearance of main shaft, is it realize 5 axle complex main shaft hair structure processed to link greatly simplify to make, it makes degree of difficulty and reducing by a large margin of the cost, the price disparity of the numerical control system shrinks. So promoted 5 axle gear beds of head of complex main shaft and compound to process the development of the lathe (process the lathe including 5).At EMO2001 exhibition, new Japanese 5 of worker machine process lathe adopt complex main shaft hair, can realize the processing of 4 vertical planes and processing of the wanton angle, make 5 times process and 5 axles are processed and can be realized on the same lathe, can also realize the inclined plane and pour the processing of the hole of awls. Germany DMG Company exhibits the DMUVoution series machining center, but put and insert and put processing and 5 axles 5 times to link and process in once, can be controlled by CNC system or CAD/CAM is controlled directly or indirectly.5.3 Become the main trend of systematic development of contemporary numerical control intelligently, openly, networkedly.The numerical control equipment in the 21st century will be sure the intelligent system, the intelligent content includes all respects in the numerical control system: It is intelligent in order to pursue the efficiency of processing and process quality, control such as the self-adaptation of the processing course, the craft parameter is produced automatically; Join the convenient one in order to improve the performance of urging and use intelligently, if feedforward control , adaptive operation , electrical machinery of parameter , discern load select models , since exactly makes etc. automatically; The ones that simplified programming , simplified operating aspect are intelligent, for instance intelligent automatic programming , intelligent man-machine interface ,etc.; There are content of intelligence diagnose , intelligent monitoring , diagnosis convenient to be systematic and maintaining ,etc..Produce the existing problem for the industrialization of solving the traditional numerical control system sealing and numerical control application software. A lot of countries carry on research to the open numerical control system at present, such as NGC of U.S.A. (The Next Generation Work-Station/Machine Control), OSACA of European Community (Open System Architecture for Control within Automation Systems), OSEC (Open System Environment for Controller) of Japan, ONC (Open Numerical Control System) of China, etc.. The numerical control system melts tobecome the future way of the numerical control system open. The so-called open numerical control system is the development of the numerical control system can be on unified operation platform, face the lathe producer and end user, through changing, increasing or cutting out the structure target(numerical control function), form the serration, and can use users specially conveniently and the technical know-how is integrated in the control system, realize the open numerical control system of different variety , different grade fast, form leading brand products with distinct distinction. System structure norm of the open numerical control system at present, communication norm , disposing norm , operation platform , numerical control systematic function storehouse and numerical control systematic function software development ,etc. are the core of present research.The networked numerical control equipment is a new light spot of the fair of the internationally famous lathe in the past two years. Meeting production line , manufacture system , demand for the information integration of manufacturing company networkedly greatly of numerical control equipment, realize new manufacture mode such as quick make , fictitious enterprise , basic Entrance that the whole world make too. Some domestic and international famous numerical control lathes and systematic manufacturing companies of numerical control have all introduced relevant new concepts and protons of a machine in the past two years, if in EMO2001 exhibition, " Cyber Production Center " that the company exhibits of mountain rugged campstool gram in Japan (Mazak) (intellectual central production control unit, abbreviated as CPC); The lathe company of Japanese big Wei (Okuma ) exhibits " IT plaza " (the information technology square , is abbreviated as IT square ); Open Manufacturing Environment that the company exhibits of German Siemens (Siemens ) (open the manufacturing environment, abbreviated as OME),etc., have reflected numerical control machine tooling to the development trend of networked direction.5.4 Pay attention to the new technical standard, normal setting-up5.4.1 Design the norm of developing about the numerical control systemAs noted previously, there are better common ability, flexibility, adaptability, expanding in the open numerical control system, such countries as U.S.A. ,European Community and Japan ,etc. implement the strategic development plan one after another , carry on the research and formulation of the systematic norm (OMAC , OSACA , OSEC ) of numerical control of the open system structure, 3 biggest economies in the world have carried on the formulation that nearly the same science planned and standardized in a short time, have indicated a new arrival of period of change of numerical control technology. Our country started the research and formulation of standardizing the frame of ONC numerical control system of China too in 2000.5.4.2 About the numerical control standardThe numerical control standard is a kind of trend of information-based development of manufacturing industry. Information exchange among 50 years after numerical control technology was born was all because of ISO6983 standard, namely adopt G, M code describes how processes,。

英文原文Hydraulic SystemHydraulic presser drive and air pressure drive hydraulic fluid as the transmission is made according to the 17th century, Pascal's principle of hydrostatic pressure to drive the development of an emerging technology, the United Kingdo m in 1795 • Braman Joseph (Joseph Braman ,1749-1814), in London water as a medium to form hydraulic press used in industry, the birth of the world's first hydraulic press. Media work in 1905 will be replaced by oil-water and further improved.Hydraulic transmission There are many outstanding advantages, it is widely used, such as general industr- ial use of plastics processing machinery, the pressure of machinery, machine tools, etc.; operating machinery engineering machinery, construction machinery, agricultural machinery, automobiles, etc.; iron and steel indu- stry metallurgical machinery, lifting equipment, such as roller adjustment device; civil water projects with flo- od control and dam gate devices, bed lifts installations, bridges and other manipulation of institutions; speed turbine power plant installations, nuclear power plants, etc.; ship from the deck heavy machinery (winch), the bow doors, bulkhead valve, stern thruster, etc.; special antenna technology giant with control devices, measu- rement buoys, movements such as rotating stage; military-industrial control devices used in artillery, ship anti- rolling devices, aircraft simulation, aircraft retractable landing gear and rudder control devices and other devi- ces.A complete hydraulic system consists of five parts, namely, power components, the implementation of co- mponents, control components, auxiliary components and hydraulic oil.The role of dynamic components of the original motive fluid into mechanical energy to the pressure that the hydraulic system of pumps, it is to power the entire hydraulic system. The structure of the form of hydra- ulic pump gears are generally pump, vane pump and piston pump.Implementation of components (such as hydraulic cylinders and hydraulic motors) which is the pressure of the liquid can be converted to mechanical energy to drive the load for a straight line reciprocating movement or rotational movement.Control components (that is, the various hydraulic valves) in the hydraulic system to control and regulate the pressure of liquid, flow rate and direction. According to the different control functions, hydraulic pressure control valve can be divided into valves, flow control valves and directional control valve. Pressure control valves are divided into benefits flow valve (safety valve), pressure relief valve, sequence valve, pressure relays, etc.; flow control valves including throttle, adjusting the valves, flow diversion valve sets, etc.; directional control valve includes a one-way valve , one-way fluid control valve, shuttle valve, valve and so on. Under the control of different ways, can be divided into the hydraulic valve control switch valve, control valve and set the value of the ratio control valve.Auxiliary components, including fuel tanks, oil filters, tubing and pipe joints, seals, pressure gauge, oil level, such as oil dollars.Hydraulic oil in the hydraulic system is the work of the energy transfer medium, there are a variety of mineral oil, emulsion oil hydraulic molding Hop categories.The role of the hydraulic system is to help humanity work. Mainly by the implementation of components to rotate or pressure into a reciprocating motion.Hydraulic system and hydraulic power control signal is composed of two parts, the signal control of some parts of the hydraulic power used to drive the control valve movement.Part of the hydraulic power means that the circuit diagram used to show the different functions of the interrelationship between components. Containing the source of hydraulic pump, hydraulic motor and auxiliary components; hydraulic control part contains a variety of control valves, used to control the flow of oil, pressure and direction; operative or hydraulic cylinder with hydraulic motors, according to the actual requirements of their choice.In the analysis and design of the actual task, the general block diagram shows the actual operation of equi - pment. Hollow arrow indicates the signal flow, while the solid arrows that energy flow.Basic hydraulic circuit of the action sequence - Control components (two four-way valve) and the spring to reset for the implementation of components (double-acting hydraulic cylinder), as well as the extending and retracting the relief valve opened and closed . For the implementation of components and control components, presentations are based on the corresponding circuit diagram symbols, it also introduced ready made circuit diagram symbols.Working principle of the system, you can turn on all circuits to code. If the first implementation of components numbered 0, the control components associated with the identifier is 1. Out with the implementation of components corresponding to the identifier for the even components, then retracting and implementation of components corresponding to the identifier for the odd components. Hydraulic circuit carried out not only to deal with numbers, but also to deal with the actual device ID, in order to detect system failures.DIN ISO1219-2 standard definition of the number of component composition, which includes the following four parts: device ID, circuit ID, component ID and component ID. The entire system if only one device, device number may be omitted.Practice, another way is to code all of the hydraulic system components for numbers at this time, components and component code should be consistent with the list of numbers. This method is particularly applicable to complex hydraulic control system, each control loop are the corresponding number with the systemWith mechanical transmission, electrical transmission compared to the hydraulic drive has the following advantages:1, a variety of hydraulic components, can easily and flexibly to layout.2, light weight, small size, small inertia, fast response.3, to facilitate manipulation of control, enabling a wide range of stepless speed regulation (speed range of 2000:1).4, to achieve overload protection automatically.5, the general use of mineral oil as a working medium, the relative motion can be self-lubricating surface, long service life;6, it is easy to achieve linear motion /7, it is easy to achieve the automation of machines, when the joint control of the use of electro-hydraulic, not only can achieve a higher degree of process automation, and remote control can be achieved.The shortcomings of the hydraulic system:1, as a result of the resistance to fluid flow and leakage of the larger, so less efficient. If not handled properly, leakage is not only contaminated sites, but also may cause fire and explosion.2, vulnerable performance as a result of the impact of temperature change, it would be inappropriate in the high or low temperature conditions.3, the manufacture of precision hydraulic components require a higher, more expensive and hence the price. 4, due to the leakage of liquid medium and the compressibility and can not be strictly the transmission ratio. 5, hydraulic transmission is not easy to find out the reasons for failure; the use and maintenance requirements for a higher level of technology.In the hydraulic system and its system, the sealing device to prevent leakage of the work of media within and outside the dust and the intrusion of foreign bodies. Seals played the role of components, namely seals. Medium will result in leakage of waste, pollution and environmental machinery and even give rise to malfunctioning machinery and equipment for personal accident. Leakage within the hydraulic system will cause a sharp drop in volumetric efficiency, amounting to less than the required pressure, can not even work. Micro-invasive system of dust particles, can cause or exacerbate friction hydraulic component wear, and further lead to leakage.Therefore, seals and sealing device is an important hydraulic equipment components. The reliability of its机械专业中英文文献翻译work and life, is a measure of the hydraulic system an important indicator of good or bad. In addition to the closed space, are the use of seals, so that two adjacent coupling surface of the gap between the need to control the liquid can be sealed following the smallest gap. In the contact seal, pressed into self-seal-style and self-styled self-tight seal (ie, sealed lips) two.The three hydraulic system diseases1, as a result of heat transmission medium (hydraulic oil) in the flow velocity in various parts of the existence of different, resulting in the existence of a liquid within the internal friction of liquids and pipelines at the sam- e time there is friction between the inner wall, which are a result of hydraulic the reasons for the oil tempera- ture. Temperature will lead to increased internal and external leakage, reducing its mechanical efficiency. At the same time as a result of high temperature, hydraulic oil expansion will occur, resulting in increased com- pression, so that action can not be very good control of transmission. Solution: heat is the inherent characte -ristics of the hydraulic system, not only to minimize eradication. Use a good quality hydraulic oil, hydraulic piping arrangement should be avoided as far as possible the emergence of bend, the use of high-quality pipe and fittings, hydraulic valves, etc.2, the vibration of the vibration of the hydraulic system is also one of its malaise. As a result of hydraulic oil in the pipeline flow of high-speed impact and the control valve to open the closure of the impact of the process are the reasons for the vibration system. Strong vibration control action will cause the system to error, the system will also be some of the more sophisticated equipment error, resulting in system failures. Solutions: hydraulic pipe should be fixed to avoid sharp bends. To avoid frequent changes in flow direction, can not avoid damping measures should be doing a good job. The entire hydraulic system should have a good damping measures, while avoiding the external local oscillator on the system.3, the leakage of the hydraulic system leak into inside and outside the leakage leakage. Leakage refers to the process with the leak occurred in the system, such as hydraulic piston-cylinder on both sides of the leakage, the control valve spool and valve body, such as between the leakage. Although no internal leakage of hydra- ulic fluid loss, but due to leakage, the control of the established movements may be affected until the cause system failures. Outside means the occurrence of leakage in the system and the leakage between the external environment. Direct leakage of hydraulic oil into the environment, in addition to the system will affect the working environment, not enough pressure will cause the system to trigger a fault. Leakage into the enviro- nment of the hydraulic oil was also the danger of fire. Solution: the use of better quality seals to improve the machining accuracy of equipment.Another: the hydraulic system for the three diseases, it was summed up: "fever, with a father拉稀" (This is the summary of the northeast people). Hydraulic system for the lifts, excavators, pumping station, dynamic, crane, and so on large-scale industry, construction, factories, enterprises, as well as elevators, lifting platforms, Deng Axle industry and so on.Hydraulic components will be high-performance, high-quality, high reliability, the system sets the direction of development; to the low power, low noise, vibration, without leakage, as well as pollution control, water-based media applications to adapt to environmental requirements, such as the direction of development; the development of highly integrated high power density, intelligence, mechatronics and micro-light mini-hydraulic components; active use of new techniques, new materials and electronics, sensing and other high-tech.Hydraulic coupling to high-speed high-power and integrated development of hydraulic transmission equ- ipment, development of water hydraulic coupling medium speed and the field of automotive applications to develop hydraulic reducer, improve product reliability and working hours MTBF; hydraulic torque converter to the development of high-power products, parts and components to improve the manufacturing process tech -nology to improve reliability, promote computer-aided technology, the development of hydraulic torque con- verter and power shift transmission technology supporting the use of ; Clutch fluid viscosity should increase the quality of products, the formation of bulk to the high-power and high-speed direction.Pneumatic Industry:Products to small size, light weight, low power consumption, integrated portfolio of development, the implementation of the various types of components, compact structure, high positioning accuracy of the direction of development; pneumatic components and electronic technology, to the intelligent direction of development; component performance to high-speed, high-frequency, high-response, high-life, high temp- erature, high voltage direction, commonly used oil-free lubrication, application of new technology, new technology and new materials.(1)used high-pressure hydraulic components and the pressure of continuous work to reach 40Mpa, the maximum pressure to achieve instant 48Mpa;(2) diversification of regulation and control;(3) to further improve the regulation performance, increase the efficiency of the powertrain;(4) development and mechanical, hydraulic, power transmission of the composite portfolio adjustment gear;(5) development of energy saving, energy efficient system function;(6) to further reduce the noise;(7) Application of Hydraulic Cartridge V alves thread technology, compact structure, to reduce the oil spill Water-based hydraulic systemsWater-based hydraulic systems traditionally have been used in hot-metal areas of steel mills. The obvious advantage of water systems in these industries is their fire resistance. Water-based hydraulic systems also have obvious cost advantages over oil-based fluid. First, non-toxic, biodegradable synthetic additives for water cost $5 to $6 per gallon. One gallon of concentrate can make 20 gallons of a 5% solution, so the cost of water-based hydraulic fluid actually can be less than 30 cents per gallon.Considering the costs associated with preventing and cleaning up environmental contamination, water-based hydraulic systems hold the potential for tremendous cost savings at the plant level. Oil that has leaked already becomes a very important problem. It must be collected, properly contained. Water containing synthetic additives, however, can by dumped into plant effluent systems.Cost savings at the plant level don&#39;t stop at the lower cost of the fluid and its disposal. Because water-based hydraulic fluid consists of 10 parts water and one part synthetic additive, 5 gallons of additive mixes with water to make 100 gallons of water-based fluid. A 50gallon container is certainly easier to handle than two 55-gallon drums, so warehousing is simpler, cleaner, and less cluttered. Transportation costs also are lower.Other potential plant-wide savings include improved safety for workers because the water-based fluid is non-toxic as well as non-flammable. These attributes can reduce plant insurance rates. Spills cost less to clean up because granular absorbents or absorbent socks are unnecessary. Water is &quot;hot&quot; againThe oil embargo in the 1970s sparked interest in water-based fluids as a less-costly alternative to oils. Even the most expensive water additives became attractive when designers learned that one gallon of concentrate would make 20 gallons of fluid.As oil prices gradually dropped, so did interest in water-based hydraulics. In retrospect, interest in water-based fluids centered around their cost saving potential. Most designers lost interest when they discovered that they could not just change the fluid in their systems from oil to water without making other substantial changes. They then become reluctant to accept other &quot;disadvantages&quot; - read substantial changes - of switching over to water-based hydraulics.What were viewed as disadvantages were really different rules that apply to water-based hydraulic systems? Designers probably resisted learning more about water-based hydraulics because they were intimated by all the work required to lean about how to design a new system or retrofit an older system. By closing their minds to this different technology, they missed the many other advantages of water-based fluid beyond initial cost. Now that environmental concerns have added disposal costs to the price of hydraulic fluids, water-based hydraulics has again become a hot topic.Fighting freezeWater-based hydraulic systems do, of course, have limits to their applications. One limitation is the potential of freezing. This possibility is probably the most significant blockade to more widespread application of机械专业中英文文献翻译water-based systems, especially in the mobile equipment industry. Longwall mining is by far the largest sector of mobile equipment that has been able to take advantage of water-based systems. Temperatures underground do not approach the freezing point of water, and fire resistance is essential. Mobile and even marine equipment used in temperate climates could cash in one the advantages of water based systems, but there is no guarantee that such equipment always will be used in above-freezing temperatures.Nevertheless, adding an anti-freeze to a water-based fluid can depress its freezing temperature to well below 32°F. Ethylene glycol - used in automotive anti-freeze - is toxic and is not biodegradable, so its use for anti-freeze in water-based hydraulic fluid would defeat the environmental advantage water-based fluid has. There is an alternative. Propylene glycol is not toxic and is biodegradable. It costs more than ethylene glycol and is not quite as effective antifreeze, so it must be used in slightly higher concentrations. Two more techniques to reduce freezing potential are to keep fluid circulating continuously and use hose where practical. Sealing the systemTwo more perceived problems with water hydraulic systems are bacterial infestation and difficulty in maintain proper concentrations. Sealing the system from atmosphere can hold bacterial growth in check. Addition of an anti-bacterial agent to the fluid can have a lasting effect on preventing bacterial buildup if air is excluded from the system.A sealed reservoir eliminates another problem suffered by many hydraulic systems: water ingression. This addresses another misconception about water-based systems: water-based systems not sealed from the atmosphere must be closely monitored to ensure that the additive concentration stays within tolerance. That is because water evaporates from the reservoir more readily than the additive does. Consequently, water evaporation causes the additive concentration to increase. When new fluid is added to a system, samples of the existing fluid must be taken to determine the concentration of additive in solution. These results then reveal the ratio of additive to fluid that must be added so that fluid concentration is correct.With a system that seals fluid from the atmosphere, the evaporation problem is virtually eliminated. Fluid that escapes by leakage is a solution containing water and additive. Therefore, the quantity of fluid in the system changes, but concentration does not. System fluid is replen ished simply by adding a pre-mixed solution of water and additive to the reservoir.中文原文液压传动液压传动和气压传动称为流体传动，是根据17世纪帕斯卡提出的液体静压力传动原理而发展起来的一门新兴技术，1795年英国约瑟夫•布拉曼(Joseph Braman,1749-1814)，在伦敦用水作为工作介质，以水压机的形式将其应用于工业上，诞生了世界上第一台水压机。

Machine design theoryThe machine design is through designs the new product or improves the old product to meet the human need the application technical science. It involves the project technology each domain, mainly studies the product the size, the shape and the detailed structure basic idea, but also must study the product the personnel which in aspect the and so on manufacture, sale and use question.Carries on each kind of machine design work to be usually called designs the personnel or machine design engineer. The machine design is a creative work. Project engineer not only must have the creativity in the work, but also must in aspect and so on mechanical drawing, kinematics, engineerig material, materials mechanics and machine manufacture technology has the deep elementary knowledge.If front sues, the machine design goal is the production can meet the human need the product. The invention, the discovery and technical knowledge itself certainly not necessarily can bring the advantage to the humanity, only has when they are applied can produce on the product the benefit. Thus, should realize to carries on before the design in a specific product, must first determine whether the people do need this kind of productMust regard as the machine design is the machine design personnel carries on using creative ability the product design, the system analysis and a formulation product manufacture technology good opportunity. Grasps the project elementary knowledge to have to memorize some data and the formula is more important than. The merely service data and the formula is insufficient to the completely decision which makes in a good design needs. On the other hand, should be earnest precisely carries on all operations. For example, even if places wrong a decimal point position, also can cause the correct design to turn wrongly.A good design personnel should dare to propose the new idea, moreover is willing to undertake the certain risk, when the new method is not suitable, use original method. Therefore, designs the personnel to have to have to have the patience, because spendsthe time and the endeavor certainly cannot guarantee brings successfully. A brand-new design, the request screen abandons obsoletely many, knows very well the method for the people. Because many person of conservativeness, does this certainly is not an easy matter. A mechanical designer should unceasingly explore the improvement existing product the method, should earnestly choose originally, the process confirmation principle of design in this process, with has not unified it after the confirmation new idea.Newly designs itself can have the question occurrence which many flaws and has not been able to expect, only has after these flaws and the question are solved, can manifest new goods come into the market the product superiority. Therefore, a performance superior product is born at the same time, also is following a higher risk. Should emphasize, if designs itself does not request to use the brand-new method, is not unnecessary merely for the goal which transform to use the new method.In the design preliminary stage, should allow to design the personnel fully to display the creativity, not each kind of restraint. Even if has had many impractical ideas, also can in the design early time, namely in front of the plan blueprint is corrected. Only then, only then does not send to stops up the innovation the mentality. Usually, must propose several sets of design proposals, then perform the comparison. Has the possibility very much in the plan which finally designated, has used certain not in plan some ideas which accepts.How does the psychologist frequently discuss causes the machine which the people adapts them to operate. Designs personnel''s basic responsibility is diligently causes the machine to adapt the people. This certainly is not an easy work, because certainly does not have to all people to say in fact all is the most superior operating area and the operating process.Another important question, project engineer must be able to carry on the exchange and the consultation with other concerned personnel. In the initial stage, designs the personnel to have to carry on the exchange and the consultation on the preliminary design with the administrative personnel, and is approved. This generally is through the oral discussion, the schematic diagram and the writing material carries on. In order to carry on the effective exchange, needs to solve the following problem:(1) designs whether this product truly does need for the people? Whether there is competitive ability(2) does this product compare with other companies'' existing similar products?(3) produces this kind of product is whether economical?(4) product service is whether convenient?(5) product whether there is sale? Whether may gain?Only has the time to be able to produce the correct answer to above question. But, the product design, the manufacture and the sale only can in carry on to the above question preliminary affirmation answer foundation in. Project engineer also should through the detail drawing and the assembly drawing, carries on the consultation together with the branch of manufacture to the finally design proposal.Usually, can have some problem in the manufacture process. Possibly can request to some components size or the common difference makes some changes, causes the components the production to change easily. But, in the project change must have to pass through designs the personnel to authorize, guaranteed cannot damage the product the function. Sometimes, when in front of product assembly or in the packing foreign shipment experiment only then discovers in the design some kind of flaw. These instances exactly showed the design is a dynamic process. Always has a better method to complete the design work, designs the personnel to be supposed unceasingly diligently, seeks these better method.Recent year, the engineerig material choice already appeared importantly. In addition, the choice process should be to the material continuously the unceasing again appraisal process. The new material unceasingly appears, but some original materials can obtain the quantity possibly can reduce. The environmental pollution, material recycling aspect and so on use, worker''s health and security frequently can attach the new limiting condition to the choice of material. In order to reduce the weight or saves the energy, possibly can request the use different material. Comes from domestic and international competition, to product service maintenance convenience request enhancement and customer''s aspect the and so on feedback pressure, can urge the people to carry on to the material reappraises. Because the material does not select when created the product responsibility lawsuit, has already had the profoundinfluence. In addition, the material and between the material processing interdependence is already known by the people clearly. Therefore, in order to can and guarantees the quality in the reasonable cost under the premise to obtain satisfaction the result, project engineer makes engineers all to have earnestly carefully to choose, the determination and the use material.Makes any product the first step of work all is designs. Designs usually may divide into several explicit stages: (a) preliminary design; (b) functional design; (c) production design. In the preliminary design stage, the designer emphatically considered the product should have function. Usually must conceive and consider several plans, then decided this kind of thought is whether feasible; If is feasible, then should makes the further improvement to or several plans. In this stage, the question which only must consider about the choice of material is: Whether has the performance to conform to the request material to be possible to supply the choice; If no, whether has a bigger assurance all permits in the cost and the time in the limit develops one kind of new material.In the functional design and the engineering design stage, needs to make a practical feasible design. Must draw up the quite complete blueprint in this stage, chooses and determines each kind of components the material. Usually must make the prototype or the working model, and carries on the experiment to it, the appraisal product function, the reliability, the outward appearance and the service maintenance and so on. Although this kind of experiment possibly can indicate, enters in the product to the production base in front of, should replace certain materials, but, absolutely cannot this point take not earnestly chooses the material the excuse. Should unify the product the function, earnestly carefully considers the product the outward appearance, the cost and the reliability. Has the achievement very much the company when manufacture all prototypes, selects the material should the material which uses with its production in be same, and uses the similar manufacture technology as far as possible. Like this has the advantage very much to the company. The function complete prototype if cannot act according to the anticipated sales volume economically to make, or is prototypical and the official production installment has in the quality and the reliable aspect is very greatly different, then this kind of prototypedoes not have the great value. Project engineer is best can completely complete the material in this stage the analysis, the choice and the determination work, but is not remains it to the production design stage does. Because, is carries on in the production design stage material replacement by other people, these people are inferior to project engineer to the product all functions understanding. In the production design stage, is should completely determine with the material related main question the material, causes them to adapt with the existing equipment, can use the existing equipment economically to carry on the processing, moreover the material quantity can quite be easy to guarantee the supply.In the manufacture process, inevitably can appear to uses the material to make some changes the situation. The experience indicated that, may use certain cheap materials to take the substitute. However, in the majority situation, in will carry on the production later to change the material to have in to start before the production to change the price which the material will spend to have to be higher than. Completes the choice of material work in the design stage, may avoid the most such situations. Started after the production manufacture to appear has been possible to supply the use the new material is replaces the material the most common reason. Certainly, these new materials possibly reduce the cost, the improvement product performance. But, must carry on the earnest appraisal to the new material, guarantees its all performance all to answer the purpose. Must remember that, the new material performance and the reliable very few pictures materials on hand such understood for the people. The majority of products expiration and the product accident caused by negligence case is because in selects the new material to take in front of substitution material, not truly understood their long-term operational performance causes.The product responsibility lawsuit forces designs the personnel and the company when the choice material, uses the best procedure. In the material process, five most common questions are: (a) did not understand or cannot use about the material application aspect most newly the best information paper; (b) has not been able to foresee and to consider the dusk year possible reasonable use (for example to have the possibility, designs the personnel also to be supposed further to forecast and the consideration because product application method not when creates consequence.ecent years many products responsibilities lawsuit case, because wrongly uses theplaintiff which the product receives the injury to accuse produces the factory, and wins the decision); (c) uses the material data not entire perhaps some data are indefinite, works as its long-term performance data is the like this time in particular;(d) the quality control method is not suitable and not after the confirmation; (e) the personnel which completely is not competent for the post by some chooses the material.Through to the above five questions analysis, may obtain these questions is does not have the sufficient reason existence the conclusion. May for avoid these questions to these questions research analyses the appearance indicating the direction. Although uses the best choice of material method not to be able to avoid having the product responsibility lawsuit, designs the personnel and the industry carries on the choice of material according to the suitable procedure, may greatly reduce the lawsuit the quantity.May see from the above discussion, the choice material people should to the material nature, the characteristic and the processing method have comprehensive and thebasic understanding.翻译：机械设计理论机械设计，通过设计新产品或改进老产品，以满足人类需要的应用技术科学。

中英文对照外文翻译文献(文档含英文原文和中文翻译)原文：Drilling and Milling MachinesUpright drilling machines or drill presses are available in a variety of sizes and types, and are equipped with a sufficient range of apindle speeds and automatic feeds to fit the neds of most industries. Speed ranges on a typical machine are from 76 to 2025 rpm., with drill feed from 0.002 to 0.020 in.per revolution of the spindle.Radial drilling machines are used to drill workpieces that are too largeor cumbersome to conveniently move. The spindle with the speed and feed changing mechanism is mounted on the radial arm; by combining the movement of the radial arm around column and the movement of the spindle assembly along the arm, it is possible to align the spindle and the drill to any position within reach of the machine. For work that is too large to conveniently support on the base, the spindle assembly can be swung out over the floor and the workpiece set on the beside the machine.Plain radial drilling machines provide only for vertical movement of the spindle; universal machines allow the spindle to swivel about an axis normal to the radial arm and the radial arm to rotate about a horizontal axis, thus permitting drilling at any angle.A multispindle drilling machine has one or more heads that drive the spindles through universal joints and telescoping splined shafts. All spindles are usually driven by the same motor and fed simultaneously to drill the desired number of holes. In most machines each spindle is held in an adjustable plate so that it can be moved relative to the others. The area covered by adjacent spindles overlap so that the machine can be set to drill holes at any location within its range.The milling operation involves metal removal with a rotating cutter. It includes removal of metal from the surface of a workspiece, enlarging holes, and form cutting, such as threads and gear teeth.Within an knee and column type of milling machine the column is themain supporting member for the other components, and includes the base containing the drive motor, the spindle, and the cutters. The cutter is mounted on an arbor held in the spindle, and supported on its outer extremity by a bearing in the overarm. The knee is held on the column in dovetail slots, the saddle is fastened to the knee in dovetail slots, and the table is attached to the saddle. Thus, the build-up the knee and column machine provides three motions relative to the cutter. A four motion may be provided by swiveling the table around a vertical axis provided on the saddle.Fixed-bed milling machines are designed to provide more rigidity than the knee and column type. The table is mounted directly on the machine base, which provides the rigidity necessary for absorbing heavy cutting load, and allows only longitudinal motion to the table. Vertical motion is obtained by moving the entire cutting head.Tracer milling is characterized by coordinated or synchronized movements of either the paths of the cutter and tracing elements, or the paths of the workpiece and model. In a typical tracer mill the tracing finger follow the shape of the master pattern, and the cutter heads duplicate the tracer motion.The following are general design considerations for milling:1. Wherever possible, the part should be designed so that a maximum number of surfaces can be milled from one setting.2. Design for the use of multiple cutters to mill several surfaces simultaneously.3. The largest flat surface will be milled first, so that all dimensions are best referred to such surface.4. Square inside corners are not possible, since the cutter rotates.Grinding Machines and Special Metal-removal ProcessRandom point-cutting tools include abrasives in the shape of a wheel, bonded to a belt, a stick, or simply suspended in liquid. The grinding process is of extreme importance in production work for several reasons.1.It is most common method for cutting hardened tool steel or other heat-treated steel. Parts are first machined in the un-heat-treated condition, and then ground to the desired dimensions and surface finish.2.It can provide surface finish to 0.5µm without extreme cost.3.The grinding operation can assure accurate dimensions in a relatively short time, since machines are built to provide motions in increments of ten-thousandths of an inch, instead of thousandths as is common in other machines.4.Extremely small and thin parts can be finished by this method, since light pressure is used and the tendency for the part to deflect away from the cutter is minimized.On a cylindrical grinding machine the grinding wheel rotates between 5500 and 6500 rpm., while the work rotates between 60 and 125 rpm... The depth of cut is controlled by moving the wheel head, which includes both the wheel and its drive motor. Coolants are provided to reduce heat distortion and to remove chips and abrasive dust.Material removal from ductile materials can be accomplished by using a tool which is harder than the workpiece. However during Word War Ⅱ the widespread use of materials which were as hard or harder than cutting tools created a demand for new material-removal methods. Since then a number of processes have been developed which, although relatively slow and costly, can effectively remove excess material in a precise and repeatable fashion. There are two types of processes. The first type is based on electrical phenomena and is used primarily for hard materials; the second depends upon chemical dissolution.Chemical milling is controlled etching process using strong alkaline or acid etchants. Aluminum, titanium, magnesium, and steel are the principal metals processed by this method. The area to remain untouched by the etchant are masked with a protective coating. For example, the entire part may be dipped in the masking material and the mask removed from those areas to be etched, or a chemically resistant prescribed time, after which the part is rinsed in cold water, the masking removed, the part inspected, and thoroughly cleaned.There are certain disadvantages to consider. Metal will erode equally in all directions, so that walls of the etched section will have a radius equal to the depth of etch. A second disadvantage is that a better finish is obtained on surfaces parallel to the direction of rolling of a sheet than on surface perpendicular to the direction of rolling. This can be compared to the surface obtained when working wood parallel to, or across the grain.A third disadvantage, not unique with this process, is the warpage that will occur in thin, previously stressed sections etched on just one side.Chemical milling, however, has many advantages over conventional metal-removal methods. There is no warpage of heavy sections such as forgings or extrusions when the etchant is applied simultaneously to all sides for reduction of section thickness. In conventional milling only one side can be worked at a time, and frequent turning of a part is necessary to prevent warpage. Chemical milling can be applied to parts of irregular shape where conventional milling may be very difficult. Light-weight construction can be obtained with chemical milling by the elimination of welding, riveting, and stiffeners; parts can be contoured to distribute the load in the most suitable manner. As an example of the potential savings of this process, as compared to machine milling, one company reports that the cost of removing aluminum by chem.-milling is $0.27 per pound as compared to $1.00 per pound by conventional milling. The rate of metal removal for chem.-milling is 0.001in. for aluminum.Electric-discharge machining is a process in which an electrical potential is impressed between the workpiece and the tool, and the current, emanating from a point source on the workpoiece, flows to the tool in the form of a spark. The forces that accomplish the metal removal are within the workpiece proper and, as a result, it is not necessary to construct the unit to withstand the heavy pressures and loads prevalent with conventional machining methods.The frequency of the electrical discharge ranges from 20,00 cps (cycles per second) for rough machining, to 50,000 cps for finishing such items as hardened tools and dies. The current may vary from 50 amp, during rough machining, to as low as 0.5 amp, during finishing. The process is currently applied to the machining of single-point tools, form tools, milling cutters, broaches, and die cavities. It is also applicable to the removal of broken drills, taps, and studs without damaging the workpiece in which the broken tool is imbedded. Other uses are the machining of oil holes in a hardened part, and the machining of small safety-wire holes in the heads of special alloy bolts, such as titanium.The ultrasonic machining process is applied to both conducting and non-conducting material, and relies entirely upon abrasive action for metal removal. The workpiece is submerged in slurry of finely fivided abrasive particles in a vehicle such as water. The tool is coupled to an oscillator and vibrates at frequencies between 15,000 and 30,000 cps. Thevibrating tool cavitates the liquid, and the force drives the abrasive into the surface of the workpiece to remove metal chips which are carried away by the liquid. The acceleration given the abrasive grains is as much as 100,000 times the acceleration of gravity, providing a smooth and rapid cutting force.Introduction of MachiningMachining as a shape-producing method is the most universally used and the most important of all manufacturing processes. Machining is a shape-producing process in which a power-driven device causes material to be removed in chip form. Most machining is done with equipment that supports both the work piece and cutting tool although in some cases portable equipment is used with unsupported workpiece.Low setup cost for small quantities. Machining has tow applications in manufacturing. For casting, forging, and pressworking, each specific shape to be p5roduced, even one part, nearly always has a high tooling cost. The shapes that may be produced, even one part, nearly always has a high tooling cost. The shapes that may be produced by welding depend to a large degree on the shapes of raw material that are available. By making use of generally high cost equipment but without special tooling, it is possible, bu machining, to start with nearly any form of any material, so long as the exterior dimensions are great enough, and produce any desiredshape from any material. Therefore, machining is usually the preferred method for producing one or a few parts, even when the design of the part would logically lead to casting, forging or pressworking if a high quantity were to be produced.Close accuracies, good finishes. The second application for machining is based on the high accuracies and surface finishes possible. Many of the parts machined in low quantities would be produced with lower but acceptable tolerances if produced in high quantities by some other process. On the other hand, many pars are given shapes by some high quantity deformation process and machined only on selected surfaces where high accuracies are needed. Internal threads, for example, are seldom produced by any means other than machining and small holes in pressworked parts may be machined following the pressworking operations.钻床和铣削直式钻床或钻孔式印刷机可用于各种尺寸和种类，它能安装轴速度的足够范围和自动运转以适应大多工业的要求。

TOOL WEAR MECHANISMS ON THE FLANK SURFACE OF CUTTINGINSERTSFOR HIGH SPEED WET MACHINING5.1 IntroductionAlmost every type of machining such as turning, milling, drilling, grinding..., uses a cutting fluid to assist in the cost effective production of pa rts as set up standard required by the producer [1]. Using coolant with some cutting tools material causes severe failure due to the lack of their resistance to thermal shock (like AL2O3 ceramics), used to turn steel. Other cutting tools materials like cubic boron nitride (CBN) can be used without coolant, due to the type of their function. The aim of using CBN is to raise the temperature of the workpice to high so it locally softens and can be easily machined.The reasons behind using cutting fluids can be summarized as follows.® Extending the cutting tool life achieved by reducing heat generated and as a result less wear rate is achieved. It will also eliminate the heat from theshear zone and the formed chips.® Cooling the work piece of high quality materia l under operation plays an important role since thermal distortion of the surface and subsurfacedamage is a result of excessive heat that must be eliminated or largelyreduced to produce a high quality product.Reducing cutting forces by its lubricating e ffect at the contact interface region and washing and cleaning the cutting region during machining from small chips. The two main reasons for using cutting fluids are cooling and lubrication.Cutting Fluid as a Coolant:The fluid characteristics and condition of use determine the coolant action of the cutting fluid, which improves the heat transfer at the shear zone between the cutting edge, work piece, and cutting fluid. The properties of the coolant in this case must include a high heat capacity to carry away heat and good thermal conductivity to absorb the heat from the cutting region. The water-based coolant emulsion with its excellent high heat capacity is able to reduce tool wear [44]. Cutting Fluid as a Lubricant:The purpose is to reduce friction bet ween the cutting edge, rake face and the work piece material or reducing the cutting forces (tangential component). As the friction drops the heat generated isdropped. As a result, the cutting tool wear rate is reduced and the surface finish is improved.Cutting Fluid PropertiesFree of perceivable odorPreserve clarity throughout lifeKind and unirritated to skin and eyes.Corrosion protection to the machine parts and work piece.Cost effective in terms off tool life, safety, dilution ratio, and fluid lif e.[1]5.1.1 Cutting Fluid TypesThere are two major categories of cutting fluidsNeat Cutting OilsNeat cutting oils are poor in their coolant characteristics but have an excellent lubricity. They are applied by flooding the work area by a pump and re-circulated through a filter, tank and nozzles. This type is not diluted by water, and may contain lubricity and extreme-pressure additives to enhance their cutting performance properties. The usage of this type has been declining for their poor cooling ability, causing fire risk, proven to cause health and safety risk to the operator [1].® Water Based or Water Soluble Cutting FluidsThis group is subdivided into three categories:1.Emulsion ` mineral soluble' white-milky color as a result of emulsion of oil inwater. Contain from 40%-80% mineral oil and an emulsifying agent beside corrosion inhibitors, beside biocide to inhibit the bacteria growth.2.Micro emulsion `semi-synthetic' invented in 1980's, has less oil concentrationand/or higher emulsifier ratio 10%-40% oil. Due to the high levels ofemulsifier the oil droplet size in the fluid are smaller which make the fluid more translucent and easy to see the work piece during operation. Otherimportant benefit is in its ability to emulsify any leakage of oil from themachine parts in the cutting fluid, a corrosion inhibitors, and bacteria control.3.Mineral oil free `synthetic' is a mix of chemicals, water, bacteria control,corrosion inhibitors, and dyes. Does not contain any mineral oils, andprovides good visibility.23 to the work piece. bare in mind that the lack of mineral oil in this type of cuttingfluid needs to take more attention to machine parts lubrication since it should not leave an oily film on the machine parts, and might cause seals degradation due the lack of protection.5.1.2 Cutting Fluid SelectionMany factors influence the selection of cutting fluid; mainly work piece material, type of machining operation, machine tool parts, paints, and seals. Table 5-1 prepared at the machine tool industry res earch association [2] provides suggestions on the type of fluid to be used.5.1.3 Coolant ManagementTo achieve a high level of cutting fluids performance and costeffectiveness, a coolant recycling system should be installed in the factory. This system will reduce the amount of new purchased coolant concentrate and coolant disposable, which will reduce manufacturing cost. It either done by the company itself or be rented out, depends on the budget and management policy of the company [1].Table 5-1 Guide to the selection of cutting fluids for general workshop applications.Machining operation Workpiece materialFree machining and low - carbon Medium- Carbon steels High Carbon and alloy steels Stainlessand heattreated GrindingClear type soluble oil, semi synthetic or chemical Turning General purpose, soluble oil, semi synthetic or synthetic fluid Extreme-pressuresoluble oil,semi-synthetic orsyntheticfluid Milling General purpose, soluble oil, semi synthetic or synthetic Extreme- pressure soluble oil, semi- synthetic or synthetic Extreme-pressuresoluble oil,semi-synthetic orsyntheticfluid(neat cutting oilsmay beDrillingExtreme- pressure soluble oil, semi- synthetic or GearShapping Extreme-pressure soluble oil, Neat-cutting oils preferable HobbingExtreme-pressure soluble oil, semi-synthetic or synthetic fluid (neat cutting oils may be Neat-cutti ng oils BratchingExtreme-pressure soluble oil, semi-synthetic or synthetic fluid (neat Tapping Extreme-pressure soluble oil, semi-synthetic or Neat-cuttingpreferableNote: some entreis deliberately extend over two or more columns, indicating awide range of possible applications. Other entries are confined to aspecific class of work material.Adopt ed f rom Edw ard and Wri ght [2]5.2 Wear Mechanisms Under Wet High Speed M achiningIt is a common belief that coolant usage in metal cutting reduces cuttingtemperature and extends tools life. However, this researchshowed that this is not necessarily true to be generalized overcutting inserts materials. Similar research was ca rried out ondifferent cutting inserts materials and cutting conditionssupporting our results. Gu et al [36] have recorded adifference in tool wear mechanisms between dry and wetcutting of C5 milling inserts. Tonshoff et al [44] alsoexhibited different wear mechanisms on AL 2O 3/TiC inserts inmachining ASTM 5115, when using coolants emulsionscompared to dry cutting. In addition, Avila and Abrao [20]experienced difference in wear mechanisms activated at theflank side, when using different coolants in t estingAL 2O 3lTiC tools in machining AISI4340 steel. The wearmechanisms and the behavior of the cutting inserts studied inthis research under wet high speed-machining (WHSM)condition is not fully understood. Therefore, it was theattempt of this research to focus on the contributions incoating development and coating techniques of newlydeveloped materials in order to upgrade their performance attough machining conditions. This valuable research providesinsight into production timesavings and increase inprofitability. Cost reductions are essential in the competitiveglobal economy; thus protecting local markets and consistingin the search of new ones.5.3 Experimental Observations on Wear Mechanisms of Un-CoatedCemented Carbide Cutting Inserts in High Speed WetMachiningIn this section, the observed wear mechanisms are presented of uncoated cemented carbide tool (KC313) in machining ASTM 4140 steel under wet condition. The overall performance of cemented carbide under using emulsion coolant has been improved in terms of extending tool life and reducing machining cost. Different types of wear mechanisms were activated at flank side of cutting inserts as a result of using coolant emulsion during machining processes. This was due to the effect of coolant in reducing the average temperature of the cutting tool edge and shear zone during machining. As a result abrasive wear was reduced leading longer tool life. The materials of cutting tools behave differently to coolant because of their varied resistance to thermal shock. The following observations recorded the behavior of cemented carbide during high speed machining under wet cutting.Figure5-1 shows the flank side of cutting inserts used at a cutting speed of 180m/min. The SEM images were recorded after 7 minutes of machining. It shows micro-abrasion wear, which identified by the narrow grooves along the flank side in the direction of metal flow, supported with similar observations documented by Barnes and Pashby [41] in testing through-coolant-drilling inserts of aluminum/SiC metal matrix composite. Since the cutting edge is the weakest part of the cutting insert geometry, edge fracture started first due to the early non-smooth engagement between the tool and the work piece material. Also, this is due to stress concentrations that might lead to a cohesive failure on the transient filleted flank cutting wedge region [51, 52]. The same image of micro-adhesion wear can be seen at the side and tool indicated by the half cone27 shape on the side of cutting tool. To investigate further, a zoom in view was taken atthe flank side with a magnification of 1000 times and presented in Figure 5-2A. It shows clear micro-abrasion wear aligned in the direction of metal flow, where the cobalt binder was worn first in a hi gher wear rate than WC grains which protruded as big spherical droplets. Figure 5-2B provides a zoom-in view that was taken at another location for the same flank side. Thermal pitting revealed by black spots in different depths and micro-cracks, propagated in multi directions as a result of using coolant. Therefore, theii~ial pitting, micro-adhesion and low levels of micro-abrasion activated under wet cutting; while high levels of micro-abrasion wear is activated under dry cutting (as presented in the prev ious Chapter).Figure 5-3A was taken for a cutting insert machined at 150mlmin. It shows a typical micro-adhesion wear, where quantities of chip metal were adhered at the flank side temporarily. Kopac [53] exhibited similar finding when testing HSS-TiN drill inserts in drilling SAE1045 steel. This adhered metal would later be plucked away taking grains of WC and binder from cutting inserts material and the process continues. In order to explore other types of wear that might exist, a zoom-in view with magnification of 750 times was taken as shown in Figure5-3B. Figure 5-3B show two forms of wears; firstly, micro-thermal cracks indicated by perpendicular cracks located at the right side of the picture, and supported with similar findings of Deamley and Trent [27]. Secondly, micro-abrasion wear at the left side of the image where the WC grains are to be plucked away after the cobalt binder was severely destroyed by micro-abrasion. Cobalt binders are small grains and WC is the big size grains. The severe distort ion of the binder along with the WC grains might be due to the activation of micro-adhesion and micro-abrasionFigure 5-1 SEM image of (KC313) showing micro abrasion and micro-adhesion (wet).SEM micrographs of (KC313) at 180m/min showing micro-abrasion where cobalt binder was worn first leaving protruded WC spherical droplets (wet).(a)SEM micrographs of (KC313) at 180m/min showing thermal pitting (wet).Figure 5-2 Magnified views of (KC313) under wet cutting: (a) SEM micrographs of (KC313) at 180mlmin showing micro-abrasion where cobalt binderwas worn first leaving protruded WC spherical droplets (wet ), (b) SEMmicrographs of (KC313) at 180.m/min showing thermal pitting (wet ).SEM image showing micro-adhesion wear mechanism under 150m/min (wet).(a)SEM image showing micro-thermal cracks, and micro-abrasion.Figure 5-3 Magnified views of (KC313) at 150m/min (wet): (a) SEM image showing micro-adhesion wear mechanism under 150m/min (wet), (b) SEM image showing micro-fatigue cracks, and micro-abrasion (wet).Wear at the time of cutting conditions of speed and coolant introduction. Therefore, micro-fatigue, micro-abrasion, and micro-adhesion wear mechanisms are activated under wet condition, while high levels of micro-abrasion were observed under dry one.Next, Figure 5-4A was taken at the next lower speed (120m/min). It shows build up edge (BUE) that has sustained its existence throughout the life of the cutting tool, similar to Huang [13], Gu et al [36] and Venkatsh et al [55]. This BUE has protected the tool edge and extended its life. Under dry cutting BUE has appeared at lower speeds (90 and 60 m/min), but when introducing coolant BUE started to develop at higher speeds, This is due to the drop in shear zone temperature that affected the chip metal fl ow over the cutting tool edge, by reducing the ductility to a level higher than the one existing at dry condition cutting. As a result, chip metal starts accumulating easier at the interface between metal chip flow, cutting tool edge and crater surface to form a BUE. In addition to BUE formation, micro-abrasion wear was activated at this speed indicated by narrow grooves.To explore the possibility of other wear mechanisms a zoom-in view with a magnification of 3500 times was taken and shown in Figure 5-4B. Micro- fatigue is evident by propagated cracks in the image similar to Deamley and Trent [27] finding. Furthermore, Figure 5-4B shows indications of micro-abrasion wear, revealed by the abrasion of cobalt binder and the remains of big protruded WC grains. However, the micro-abrasion appeared at this speed of 120m/min is less severe than the same type of micro-wear observed at 150m/min speed, supported with Barnes [41] similar findings. Therefore, micro-abrasion, BUE and micro-fatigue were activated under wet condition while, adhesion, high levels micro-abrasion, and no BUE were under dry cutting.SEM i m a g e o f(KC313) showing build up e d g e under 120m/min (wet).(a)SEM i m a g e o f(KC3 13) showing micro-fatigue, and micro-abrasion (wet). Figure 5-4 SEM images of (KC313) at 120m/min (wet), (a) SEM image of (KC313). showing build up edge, (b) SEM image of(K C313) showing micro-fatigue and micro-abrasion33 Figure 5-5 is for a cutting tool machined at 90m/min, that presents a goodcapture of one stage of tool life after the BUE has been plucked away. The bottom part of the flank side shows massive metal adhesion from the work piece material. The upper part of the figure at the edge shows edge fracture. To stand over the reason of edge fracture, the zoom-in view with magnification of 2000 times is presented in Figure 5-6A. The micro-fatigue crack image can be seen as well as micro-attrition revealed by numerous holes, and supported with Lim et al [31] observations on HSS-TiN inserts. As a result of BUE fracture from the cutting tool edge, small quantities from the cutting tool material is plucked away leaving behind numerous holes. Figure 5-6B is another zoom-in view of the upper part of flank side with a magnification of 1000 times and shows micro-abrasion wear indicated by the narrow grooves. Furthermore, the exact type of micro-wear mechanism appeared at the flank side under 60 m/min. Therefore, in comparison with dry cutting at the cutting speed of 90 m/min and 60 m/min, less micro-abrasion, bigger BUE formation, and higher micro-attrition rate were activated.Figure 5-5 SEM image showing tool edge after buildup edge was plucked away.SEM image showing micro-fatigue crack, and micro-attrition.(a)SEM image showing micro-abrasion.Figure 5-6 SEM images of (KC313) at 90m/min:(a) SEM image showing micro-fatigue crack, and micro-attrition, (b) SEM image showingmicro-abrasion.5.4 Experimental Observations on Wear Mechanisms of Coated CementedCarbide with TiN-TiCN-TiN Coating in High Speed WetMachiningInvestigating the wear mechanisms of sandwich coating under wet cutting is presented in this section starting from early stages of wear. Figure 5-7 shows early tool wear starting at the cutting edge when cutting at 410m/min. Edge fracture can be seen, it has started at cutting edge due to non-smooth contact between tool, work piece, micro-abrasion and stress concentrations. To investigate further the other possible reasons behind edge fracture that leads to coating spalling, a zoom-in view with magnification of 2000 ti mes was taken and presented at Figure 5-8A. Coating fracture can be seen where fragments of TiN (upper coating) had been plucked away by metal chips. This took place as result of micro-abrasion that led to coating spalling. On the other hand, the edge is t he weakest part of the cutting insert geometry and works as a stress concentrator might lead to a cohesive failure on the transient filleted flank cutting wedge region [51, 52].Both abrasion wear and stress concentration factor leave a non-uniform edge configuration at the micro scale after machining starts. Later small metal fragments started to adhere at the developed gaps to be later plucked away by the continuous chip movement as shown in Figure 5-8A. Another view of edge fracture was taken of the same cutting tool with a magnification of 2000 times as shown in Figure 5-8B. It presents fracture and crack at the honed tool edge. A schematic figure indicated by Figure 5-9, presented the progressive coated cutting inserts failure starting at the insert edge. It was also noticed during the inserts test that failure takes place first at the inserts edge then progressed toward the flank side. Consequently, a study on optimizing the cutting edgeFigure 5-7 SEM image of (KC732) at 410m/min showing edge fractur e and micro-abrasion (wet).SEM image showing edge fracture.(a)SEM image showing fracture and crack at the honed insert edge.Figure 5-8 SEM of (KC732) at 410m/min and early wear stage (wet): (a) SEM image showing edge fracture, (b) SEM image showing fr acture and crack atthe honed insert edge.radius to improve coating adhesion, and its wear resistance, might be also a topic for future work.Figure 5-1.0A was taken after tool failure at a speed of 410m/min. It shows completely exposed substrate and severe sliding wear at the flank side. The coating exists at the crater surface and faces less wear than the flank side. Therefore it works as an upper protector for the cutting edge and most of the wear will take place at the flank side as sliding wear. Figu re 5-10B is a zoom-in view with magnification of 3500 times, and shows coating remaining at the flank side. Nonetheless, micro-abrasion and a slight tensile fracture in the direction of metalchip flow. Ezugwa et al [28] and Kato [32] have exhibited simila r finding. However, the tensile fracture in this case is less in severity than what had been observed at dry cutting. This is due to the contribution of coolant in dropping the cutting temperature, which has reduced the plastic deformation at high temperature as a result. Hence, in comparison with the dry cutting at the same speed, tensile fracture was available with less severity and micro-abrasion/sliding. However, in dry cutting high levels of micro-abrasion, high levels of tensile fracture and sliding wear occurred.Figure 5-11 was taken at early stages of wear at a speed of 360m/min. It shows sliding wear, coating spalling and a crack starting to develop between TiN and TiCN coating at honed tool edge. Figure5-12A shows nice presentation of what had been described earlier regarding the development of small fragments on the tool edge. The adhered metal fragments work along with micro-abrasion wear to cause coating spalling.SEM image showing sliding wear.(a)SEM image showing micro-abrasion and tensile fracture.Figure 5-10 SEM images of (KC732) at 410m/min after failure (wet): (a) SEM image showing sliding wear, (b) SEM image showing micro-abrasionand tensile fracture.Figure 5-11 SEM image at early stage of wear of 360m/min (wet) showing coating and spalling developing crack between TiN and TiCN layers.The size of the metal chip adhered at the edge is almost 15g. Since it is unstable it will be later plucked away taking some fragments of coatings with it and the process continues. Another zoom in view with a magnification of 5000 times for the same insert is shown in Figure 5-12B indicating a newly developed crack between the coating layers.Figure 5-13A is taken of the same insert after failure when machining at 360m/min and wet condition. Coating spalling, and sliding wear can be seen and indicated by narrow grooves. In addition, initial development of notch wear can be seen at the maximum depth of cut.Further investigation is carried out by taking a zoom in view with a magnification of 2000 times as shown in Figure 5-13B. A clear micro-abrasion wear and micro-fatigue cracks were developed as shown, which extended deeply through out the entire three coating layers deep until the substrate. Therefore, in comparison with dry cutting, micro-fatigue crack, less tensile fracture, less micro-abrasion wear were activated at wet cutting. While micro- fatigue crack, high levels of micro-abrasion, and high levels of tensile fracture are distinguish the type of wear under dry condition at the same cutting spee d.Next, Figure 5-14A is taken for cutting tools machined at 310m/min. The results are similar to the previous inserts machined at 360m/min, where adhesion of metal fragments occurred at the tool edge, sliding wear and coating spalling. In addition, the black spot appeared at the top of the figure on the crater surface is a void resulting from imperfections in the coating process. At this condition, the crater surface will be worn faster than the flank surface.SEM image showing adhered metal fragments at tool edge.(a)SEM image showing developed crack between coating layers.Figure 5-12 SEM image of (KC732) at early wear 360m/min (wet): (a) SEM image showing adhered metal fragments at tool edge, (b) SEM image showingdeveloped crack between coating layers.(a)SEM image showing coating spalling and sliding wear after tool failure(b)SEM image showing micro-abrasion, and micro-fatigue cracks developedbetween coating layersFigure 5-13 SEM image of KC732 after failure machined at 360m/min(b)(wet): (a) SEM image showing coating spalling and sliding wear after toolfailure, (b) SEM image showing micro-abrasion, and micro-fatiguecracks developed between coating layers.翻译：在高速潮湿机械加工条件下后刀面表层磨损机理5.1 介绍几乎每类型用机器制造譬如转动, 碾碎, 钻井, 研..., 使用切口流体协助零件的有效的生产当设定标准由生产商[ 1 ] 需要。

毕业设计(论文)外文资料翻译系部：专业：姓名：学号：外文出处：English For Electromechanical(用外文写)Engineering附件：1.外文资料翻译译文；2.外文原文。

附件1：外文资料翻译译文机床机床是用于切削金属的机器。

工业上使用的机床要数车床、钻床和铣床最为重要。

其它类型的金属切削机床在金属切削加工方面不及这三种机床应用广泛。

车床通常被称为所有类型机床的始祖。

为了进行车削，当工件旋转经过刀具时，车床用一把单刃刀具切除金属。

用车削可以加工各种圆柱型的工件，如：轴、齿轮坯、皮带轮和丝杠轴。

镗削加工可以用来扩大和精加工定位精度很高的孔。

钻削是由旋转的钻头完成的。

大多数金属的钻削由麻花钻来完成。

用来进行钻削加工的机床称为钻床。

铰孔和攻螺纹也归类为钻削过程。

铰孔是从已经钻好的孔上再切除少量的金属。

攻螺纹是在内孔上加工出螺纹，以使螺钉或螺栓旋进孔内。

铣削由旋转的、多切削刃的铣刀来完成。

铣刀有多种类型和尺寸。

有些铣刀只有两个切削刃，而有些则有多达三十或更多的切削刃。

铣刀根据使用的刀具不同能加工平面、斜面、沟槽、齿轮轮齿和其它外形轮廓。

牛头刨床和龙门刨床用单刃刀具来加工平面。

用牛头刨床进行加工时，刀具在机床上往复运动，而工件朝向刀具自动进给。

在用龙门刨床进行加工时，工件安装在工作台上，工作台往复经过刀具而切除金属。

工作台每完成一个行程刀具自动向工件进给一个小的进给量。

磨削利用磨粒来完成切削工作。

根据加工要求，磨削可分为精密磨削和非精密磨削。

精密磨削用于公差小和非常光洁的表面，非精密磨削用于在精度要求不高的地方切除多余的金属。

车床车床是用来从圆形工件表面切除金属的机床，工件安装在车床的两个顶尖之间，并绕顶尖轴线旋转。

车削工件时，车刀沿着工件的旋转轴线平行移动或与工件的旋转轴线成一斜角移动，将工件表面的金属切除。

车刀的这种位移称为进给。

车刀装夹在刀架上，刀架则固定在溜板上。

溜板是使刀具沿所需方向进行进给的机构。

机械专业外文翻译（中英文翻译）第1页Among the methods of material conveying employed，belt conveyorsplaya very important part in the reliable carrying of material over longdistances at competitive cost．Conveyor systems have become larger and morecomplex and drive systems have also been going through a process of evolutionand will continue to do so．Nowadays，bigger belts require more power and havebrought the need for larger individual drives as well as multiple drives suchas 3 drives of 750 kW for one belt(this is the case for the conveyor drivesin Chengzhuang Mine)．The ability to control drive acceleration torque iscritical to belt conveyors’ performance．An efficient drive system should beable to provide smooth，soft starts while maintaining belt tensions withinthe specified safe limits．For load sharing on multiple drives．torque andspeed control are also important considerations in the drive system’s design.Due to the advances in conveyor drive control technology，at present many morereliable．Cost-effective and performance-driven conveyor drive systems[1]covering a wide range of power are available for customers’ choices. Full-voltage starters．With a full-voltage starter design，the conveyor head shaft is direct-coupled to the motor through the gear drive．Direct full-voltage startersare adequate for relatively low-power, simple-profile conveyors．With direct fu11-voltage starters．no control is provided for various conveyor loadsand．depending on the ratio between fu11- and no-1oad power requirements，empty starting times can be three or four times faster than full load．The maintenance-free starting system is simple，low-cost and very reliable．However, they cannot control starting torque and maximum stall torque；therefore．they are第2页 limited to the low-power, simple-profile conveyor belt drives．Reduced-voltage starters．As conveyor power requirements increase，controlling the applied motor torque during the acceleration period becomes increasinglyimportant．Because motor torque 1s a function of voltage，motor voltage must be controlled．This can be achieved through reduced-voltage starters by employinga silicon controlled rectifier(SCR)．A common starting method with SCRreduced-voltage starters is to apply low voltage initially to takeup conveyorbelt slack．and then to apply a timed linear ramp up to full voltage and beltspeed．However, this starting method will not produce constant conveyor beltacceleration．When acceleration is complete．the SCRs, which control the applied voltage to the electric motor． are locked in full conduction, providing fu11-linevoltage to the motor．Motors with higher torque and pull—uptorque，can provide better starting torque when combined with the SCR starters, which are availablein sizes up to 750 KW．Wound rotor induction motors．Wound rotor induction motors are connecteddirectly to the drive system reducer and are a modifiedconfiguration of a standardAC induction motor．By inserting resistance in series with the motor’s rotor windings．the modified motor control system controlsmotor torque．For conveyor starting，resistance is placed in series with the rotor for low initial torque．As the conveyor accelerates，the resistance is reduced slowly to maintain a constantacceleration torque．On multiple-drive systems．an external slip resistor may beleft in series with the rotor windings to aid in load sharing．The motor systems have a relatively simple design．However, the control systems for these can behighly complex，because they are based on computer control of the resistanceswitching．Today，the majority of control systems are custom designed to meet aconveyor system’s particular specifications．Wound rotor motors are appropriatefor systems requiring more than 400 kW ．DC motor．DC motors．available from a fraction of thousands of kW ，are designed to deliver constant torque below base speed and constant kW above base speed tothe maximum allowable revolutions per minute(r/min)．with the majority of conveyordrives, a DC shunt wound motor is used．Wherein the motor’srotating armature is第3页 connected externally．The most common technology for controlling DC drives is aSCR device． which allows for continual variable-speed operation．The DC drive system is mechanically simple, but can include complex custom-designed electronicsto monitor and control the complete system．This system option is expensive incomparison to other soft-start systems．but it is a reliable, cost-effective drivein applications in which torque,1oad sharing and variable speed are primaryconsiderations．DC motors generally are used with higher-power conveyors，including complex profile conveyors with multiple-drive systems，booster tripper systems needing belt tension control and conveyors requiring a wide variable-speed range．Hydrokinetic couplings，commonly referred to as fluid couplings．are composed of three basic elements; the driven impeller, which acts as a centrifugal pump；the driving hydraulic turbine known as the runner and a casing that encloses thetwo power components．Hydraulic fluid is pumped from the driven impeller to thedriving runner, producing torque at the driven shaft．Because circulating hydraulicfluid produces the torque and speed，no mechanical connection is required betweenthe driving and driven shafts．The power produced by this coupling is based onthe circulated fluid’s amount and density and the torque in proportion to inputspeed．Because the pumping action within the fluid coupling depends on centrifugalforces．the output speed is less than the input speed．Referred to as slip．this normally is between l% and 3%．Basic hydrokinetic couplings are available inconfigurations from fractional to several thousand kW ．Fixed-fill fluid couplings．Fixed-fill fluid couplings are the most commonlyused soft-start devices for conveyors with simpler belt profiles and limitedconvex/concave sections．They are relativelysimple,1ow-cost,reliable,maintenance free devices that provide excellent softstarting results to the majority of belt conveyors in use today．Variable-fill drain couplings．Drainable-fluid couplings work on the sameprinciple as fixed-fill couplings．The coupling’s impellers are mounted on the ACmotor and the runners on the driven reducer high-speed shaft．Housing mounted to the drive base encloses the working circuit．The coupling’s rotating casing contains第4页 bleed-off orifices that continually allow fluid to exit the working circuit intoa separate hydraulic reservoir．Oil from the reservoir is pumped through a heatexchanger to a solenoid-operated hydraulic valve that controls the filling of thefluid coupling．To control the starting torque of a single-drive conveyor system，the AC motor current must be monitored to provide feedback to the solenoid controlvalve．Variable fill drain couplings are used in medium to high-kW conveyor systemsand are available in sizes up to thousands of kW ．The drives can be mechanicallycomplex and depending on the control parameters．the system can be electronicallyintricate．The drive system cost is medium to high, depending upon size specified．Hydrokinetic scoop control drive．The scoop control fluid coupling consistsof the three standard fluid coupling components：a driven impeller, a driving runnerand a casing that encloses the working circuit．The casing is fitted with fixedorifices that bleed a predetermined amount of fluid into a reservoir．When the scoop tube is fully extended into the reservoir, the coupling is l00 percentfilled．The scoop tube, extending outside the fluid coupling，is positioned using an electric actuator to engage the tube from the fully retracted to the fullyengaged position．This control provides reasonably smooth acceleration rates．to but the computer-based control system is very complex．Scoop control couplings are applied on conveyors requiring single or multiple drives from l50 kW to 750kW.Variable frequency control is also one of the direct drive methods．The emphasizing discussion about it here is because that it has so uniquecharacteristic and so good performance compared with other driving methods forbelt conveyor． VFC devices Provide variable frequency and voltageto the inductionmotor, resulting in an excellent starting torque and acceleration rate for beltconveyor drives．VFC drives．available from fractional to several thousand(kW ),are electronic controllers that rectify AC line power to DC and，through an inverter, convert DC back to AC with frequency and voltage contro1．VFC drives adopt vector control or direct torquecontrol(DTC)technology，and can adopt different operating speeds according to different loads．VFC drives can make starting or stalling第5页 according to any given S-curves．realizing the automatic track for starting orstalling curves．VFC drives provide excellent speed and torque control for startingconveyor belts．and can also be designed to provide load sharing for multipledrives．easily VFC controllers are frequently installed on lower-powered conveyordrives，but when used at the range of medium-high voltage in the past．the structure of VFC controllers becomes very complicated due to the limitation of voltage ratingof power semiconductor devices，the combination of medium-high voltage drives andvariable speed is often solved with low-voltage inverters usingstep-uptransformer at the output，or with multiple low-voltage inverters connected inseries．Three-level voltage-fed PWM converter systems are recently showingincreasing popularity for multi-megawatt industrial driveapplications becauseof easy voltage sharing between the series devices and improved harmonic qualityat the output compared to two-level converter systems With simple series connectionof devices．This kind of VFC system with three 750 kW /2．3kV inverters has been successfully installed in ChengZhuang Mine for one 2．7-km long belt conveyordriving system in following the principle of three-level inverterwill be discussedin detail．Three-level voltage-fed inverters have recently become more and more popularfor higher power drive applications because of their easy voltage sharingfeatures．1ower dv/dt per switching for each of the devices，and superior harmonic quality at the output．The availability of HV-IGBTs has led to the design of anew range of medium-high voltage inverter using three-level NPC topology．This kind of inverter can realize a whole range with a voltagerating from 2．3 kV to 4．1 6 kV Series connection of HV-IGBT modules is used in the 3．3 kV and 4．1[2,3]6 kV devices．The 2．3 kV inverters need only one HV-IGBT per switch.To meet the demands for medium voltage applications．a three-level neutral point clamped inverter realizes the power section．In comparison to a two-levelinverter．the NPC inverter offers the benefit that three voltage levels can besupplied to the output terminals，so for the same output current quality，only第6页1/4 of the switching frequency is necessary．Moreover the voltage ratings of theswitches in NPC inverter topology will be reduced to 1/2．and the additional transient voltage stress on the motor can also be reduced to 1/2 compared to thatof a two-level inverter．The switching states of a three-level inverter are summarized in Table 1．U．V and W denote each of the three phases respectively；P N and O are the dc bus points．The phase U，for example，is in stateP(positive bus voltage)when theswitches S and S are closed，whereas it is in state N (negative bus voltage) 1u2uwhen the switches S and S are closed．At neutral point clamping，the phase is 3u4uin O state when either Sor S conducts depending on positive or negative phase 2u 3ucurrent polarity，respectively．For neutral point voltage balancing，the average current injected at O should be zero．For standard applications．a l2-pulse diode rectifier feeds the divided DC-linkcapacitor．This topology introduces low harmonics on the line side．For even higher requirements a 24-pulse diode rectifier can be used as an input converter．For more advanced applications where regeneration capability is necessary, an activefront．end converter can replace the diode rectifier, using the same structureas the inverter．Motor Contro1．Motor control of induction machines is realized by using a rotorflux．oriented vector controller．Fig．2 shows the block diagram of indirect vector controlled drive thatincorporates both constant torque and high speed field-weakening regions wherethe PW M modulator was used．In this figure，the command flux is generated as function of speed．The feedback speed is added with the feed forward slip commandsignal . the resulting frequency signal is integrated and then the unit vectorsignals(cos and sin )are generated．The vector rotator generates the voltageand angle commands for the PW M as shown．PWM Modulator．The demanded voltage vector is generated using an elaborate第7页 PWM modulator．The modulator extends the concepts of space-vector modulation tothe three-level inverter．The operation can be explained by starting from aregularly sampled sine-triangle comparison from two-level inverter．Instead of using one set of reference waveforms and one triangle defining the switchingfrequency， the three-level modulator uses two sets of reference waveforms U and r1U and just one triangle．Thus, each switching transition is used in an optimal r2way so that several objectives are reached at the same time．Very low harmonics are generated．The switching frequency is low and thusswitching losses are minimized．As in a two-level inverter, a zero-sequencecomponent can be added to each set of reference waveform s in order to maximizethe fundamental voltage component．As an additional degree of freedom，the position of the reference waveform s within the triangle can be changed．This can be used for current balance in the two halves of the DC-1ink．After Successful installation of three 750 kW /2．3 kV three-level invertersfor one 2．7 km long belt conveyor driving system in Chengzhuang Mine．The performance of the whole VFC system was tested．Fig．3 is taken from the test，which shows the excellent characteristic of the belt conveyor driving system withVFC controller．Fig．3 includes four curves．The curve 1 shows the belt tension．From the curve it can be find that the fluctuation range of the belt tension is very smal1．Curve 2 and curve 3 indicate current and torque separately．Curve 4 shows the velocityof the controlled belt．The belt velocity have the“s”shape characteristic．A1l the results of the test show a very satisfied characteristic for belt drivingsystem．Advances in conveyor drive control technology in recent years have resultedin many more reliable．Cost-effective and performance-driven conveyor drive systemchoices for users．Among these choices，the Variable frequency control (VFC) methodshows promising use in the future for long distance belt conveyor drives due toits excellent performances．The NPC three-level inverter using high voltage IGBTs第8页 make the Variable frequency control in medium voltage applications become muchmore simple because the inverter itself can provide the medium voltage needed atthe motor terminals，thus eliminating the step-up transformer in most applicationsin the past．The testing results taken from the VFC control system with NPC three．1evel inverters used in a 2．7 km long belt conveyor drives in Chengzhuang Mine indicatesthat the performance of NPC three-level inverter using HV-IGBTs together with thecontrol strategy of rotor field-oriented vector control for induction motor driveis excellent for belt conveyor driving system．第9页在运送大量的物料时，带式输送机在长距离的运输中起到了非常重要的竞争作用。

英语原文：Design Of Tool Machine PropResearch significanceThe original knife machine control procedures are designed individually, not used tool management system, features a single comparison, the knife only has to find the tool knife, knife positioning the shortest path, axis tool change, but does not support large-scale tool.Automatic knife in the knife election, in the computer memory knife-election on the basis of using the Siemens 840 D features, and the election procedures knife more concise, and complete the space Daotao View. ATC use the knife rapid completion of STEP-7 programming, and have been tested in practice. In the positioning of the knife, PLC controlled modular design method, which future production of similar machines will be very beneficial, it is easy to use its other machine. Automatic tool change systems will be faster growth, reduced tool change time, increase the positioning accuracy tool is an important means to help NC technology development.Tool and inventory components of modern production is an important link in the management, especially for large workshop management. The traditional way of account management, and low efficiency, high error rate, and not sharing information and data, tools and the use of state can not track the life cycle, are unable to meet the current information management needs. With actual production, we have to establish a workshop tool for the three-dimensional tool storage system to meet the knife workshop with auxiliary storage and management needs.The system uses optimization technology, a large number of computer storage inventory information, timely, accurate, and comprehensive tool to reflect the inventory situation. The entire system uses a graphical interface, man-machine dialogue tips from the Chinese menu, select various functions can be realized and the importation of all kinds of information. Management system using online help function. Through the workshop management, network management and sharing of information. Have automated inventory management, warehousing management tool, a tool for the management and statistical functions.1.System components and control structureThe entire system, including the structure and electrical machinery control systems.1.1.1Mechanical structure and working principleTool from the stent, drive, drive system, Turret, shielding, control system, and electrical components. Support from the column, beam, the upper and lower guide Central track, and track support component.1) Drive for the system chosen VVVF method. Cone used brake motors, with VVVF by Cycloidreducer through sprocket drive.2) Drag a variable frequency drive system and control technology. VVVF adopted, will speed drive shaft in the normal range adjustment to control the speed rotary turret to 5 ~ 30mm in, the drive shaft into two, two under through sprocket, the two profiled rollers Chain driven rotating shelves. Expansion chain adopted by the thread tight regulation swelling, swelling the regular way. - Conditioned, under the same chain-of-conditioning, so that the chain of uniform.3) Turret and shields the entire total of 14 independent Turret. 13 of them as a socket-Turret, as a drawer-Turret, each Turret back through the pin and, under the conveyor chain link chain plate, installed at the bottom roller, chain driven rotating turret rotation along the track. Outlet-Turret and BT50-BT40 Turret Turret two kinds of forms. To strengthen management, security, landscaping modeling, shelf peripherals and shields. Turret-drawer drawer placed at six other Des V oeux a knife, can be categorized with some of knife auxiliary equipment, such as bits, such as turning tools.1.1.2.Electrical Control SystemThis tool storage systems is the main electrical control their shelves for operational control and position control. Operational control equipment, including operation of the start of braking control. Position Control is the main location and address of the shelves for testing. Control system as shown in Figure 1.图 1 Tool Control System for the1) Electric Transmission horizontal rotary tool storage systems are the mechanical movements are repeated short-term work system. And the run-time system needs some speed, speed transmission needs, the system will use VVVF method can be used simple structure, reliable operation of the motor and frequency inverter.2) Control of the system is divided into two kinds of manual control and automatic control, manual control as a general reserve and debugging methods of work; ways to the system control computer (IPC) and the control unit (inverter contactor , etc.) consisting of a control system.3) location and positioning accuracy of the system automatically identify the site and location using a detection device as proximity switches, relays through the plate-point isolation and the number plate recorded close to the switching signal acquisition and operation of Hutchison with a Optimal Path addressable identify the current location and shelves of the purpose of the shelf location. In order to enable a more accurate positioning system, adopted two photoelectric switches, to detect the two shelves of the two films.1.2.The functions of the knifeknife The is the role of reserves a certain number of tools, machine tool spindle in hand to achieve the fungibility a disc cutter knife is the type of library, the chain knives, and other means, in the form of the knife and capacity according to the Machine Tool to determine the scope of the process.mon typesThe knife is a tool storage devices, the common knife mainly in the following forms:(1) the turret knifeIncluding the first level turret vertical turret and the first two, see Figure 2.6 a) and b):(2) the disc cutterDisc knife in the library with discoid knife, cutting tool along See how vertical arrangement (including radial and axial from knife from knife), along See how radial array into acute or arranged in the form of the knife. Simple, compact, more applications, but are ring-cutter, low utilization of space. Figure 2.7 a) to c). If the knife storage capacity must be increased to increase the diameter of the knife, then the moment of inertia also increased correspondingly, the election campaign long knife. Tool number not more than 32 general. Cutter was multi-loop order of the space utilization knife, but inevitably given the knife from complex institutions,applicable to the restricted space Machine Tool storage capacity and more occasions. Two-disc structure is two smaller capacity knife on both sides of the sub-spindle place, more compactlayout, the number of certificates corresponding increase knife, apply to small and medium-sized processing center.(3) the chain knifeIncluding single-and multi-ring chain ring chain, chain link can take many forms change, see Figure 2.8 a) to c), thebasic structure shown inFigure 2. 8 doFeatures: knife apply tothe larger capacity of theoccasion, the space of thesmall number ofgenerally applicable tothe tool in the 30-120.Only increase the lengthof the chain tool will increase the number should not be increased circumferential speed of itsmoment of inertia of the knife does not increase the disc as large.(4) linear combination knife and the knife libraryThe linear knife simple structure in Figure 2.9, tool single order, the capacity of small knife, used for CNC lathe and drill press on. Because the location of fixed knife, ATC completed action by the spindle without manipulator. The cutter knife is generally the turret combination turret with a combination of the disc cutter knife and the chain combination. Every single knife the knife certificates of smaller, faster tool change. There are also some intensive drum wheel, and the lattice-type magazine for the knife, the knife-intensive though. Small footprint, but because of structural constraints, basically not used for single processing center, the concentration used for FMS for the knife system.1.4 Tool storage capacityTool storage capacity of the first to consider the needs of processing, from the use of point of view, generally 10 to 40 knives, knife will be the utilization of the high, and the structure iscompact.1.5 Tool options(1) choose to order processing tool according to the order, followed Add to the knife every knife in the Block. Each tool change, the order of rotation of a cutter knife on location, and remove the need knives, has been used by the cutter knife can be returned to the original Block, can also order Add Block, a knife. However, as the knife in the tool in different processes can not be repeated use of the knife must increase the capacity and lower utilization rate.(2) most of the arbitrary choice of the current system of using arbitrary NC election knives, divided into Daotao coding, coding and memory-cutter, three. Daotao coding tool code or knives or Daotao need to install the code used to identify, in accordance with the general principle of binary coding coding. Tool knife election coding method uses a special knife handle structure, and each of the coding tool. Each of the tool has its own code, thereby cutting tool can be in different processes repeatedly used, not to replace the tool back at the original knife, the knife capacity can be reduced accordingly. Memory-election this paper knife, in this way can knives and knife in the position corresponding to the Daotao memory of the PLC in the NC system, no matter which tool on the Inner knife, tool information is always there in mind, PLC . On the knife with position detection devices, will be the location of each Daotao. This tool can be removed and sent back to arbitrary. On the knife is also a mechanical origin, every election, the nearest knife selection.1.6.Control of the knife(1) the knife as a system to control the positioning axis. In the ladder diagram in accordance with the instructions for computing T code comparison of the output angle and speed of instructions to the knife the knife servo drive servo motor. Tool storage capacity, rotation speed, and / deceleration time, and other system parameters can be set in such a manner free from any outside influence positioning accurate and reliable but the cost is higher.(2) knife from the hydraulic motor drives, fast / slow the points, with proximity switches count and positioning. In comparison ladder diagram of the current storage system knife (knife spindle) and goals knife (pre-knife) and computing, then output rotation instructions, judging by the shortest path rotation in place. This approach requires sufficient hydraulic power and electromagnetic valve knife the rotational speed can be adjusted through the throttle. But over time may be oily hydraulic, oil temperature and environmental factors impact the change in velocity and accuracy. Not generally used in large and medium-sized machine tool change frequently.(3) the knife from AC asynchronous motor driven cam mechanism (Markov institutions), with proximity switches count, which means stable operation, and generally accurate and reliablepositioning cam used in conjunction with a mechanical hand, ATC fast-positioning.2. ATC, the main types, characteristics, and the scope of application 2.1 Auto Rotary ToolRotary Tool automatically onthe use of CNC machine tool is asimple installation of automatic toolchange, the Quartet and 47.60 TurretTool various forms, such as rotaryturret were installed on four, six ormore of the Tool , NC instructions byATC. Rotary Tool has two verticaland horizontal, relatively simplestructure, applicable to economicCNC lathe.Rotary Tool in the structure musthave good strength and stiffness,resistance to bear rough Cutting Toolin the cutting force and reduce therole of deformation and improveprocessing accuracy. Rotating Toolto choose reliable positioningprogramme structure and reasonable position, in order to ensure that each rotary turret to a higher position after repeated positioning accuracy (typically 0.001 to 0.005mm). Figure 2.1 shows the spiral movements of the Quartet Turret.Auto Rotary Tool in the simplest of ATC, is 180 º rotary ATC devices, as shown in Figure 2.2 ATC instructions received, the machine control system put ATC spindle control to the designated location at the same time, the tool movement to the appropriate location, ATC, with the rotary axis and at the same time, the knives matching tool; drawbars from Spindle Cutting Tools rip, ATC, will be the tool from their position removed; ATC, 180 º rotary tool spindle and the tool and tool away; ATC, the Rotary At the same time, the tool refocusing its position to accept Spindle removed from the cutting tool; Next, ATC, will be replaced with the cutter knives were unloaded into the spindle and tool: Finally, back to the original ATC, "standby" position. At this point, ATC completed procedures to continue to run. This ATC, the main advantage ofsimple structure, the less movement, fast tool change. The main disadvantage is that knives must be kept in parallel with the axis of the plane, and after the home side compared to the tool, chip and liquid-cutting knife into the folder, it is necessary to the tool plus protection. Cone knife folder on the chip will cause ATC error, or even damage knife folders, and the possibility of spindle. Some processing centre at the transfer, and the tool side. When the ATC command is called, the transfer-cutter knives will be removed, the machine go forward, and positioning with the ATC, in line with the position. 180 º "Rotary ATC devices can be used horizontal machine, can also be used for vertical machining centers.2. 2 ATC head-turret installedWith rotating CNC machine tool often used such ATC devices, with a few turret head spindle, each with a spindle on both knives, the first tower interim process can be automatic tool change-realization. The advantage is simple structure, tool change time is short, only about 2 s. However, due to spatial constraints, the number of spindle can not be too much, usually only apply to processes less, not to high precision machine tools, such as the NC drill, such as CNC milling machine. In recent years there has been a mechanical hand and the turret head with a knife for the automatic tool change ATC devices, as shown in Figure 2.3. It is in fact a turret head ATC, and the knife-ATC device combination. The principle is as follows:5 turret on the first two tool spindle 3 and 4, when using the tool spindle 4 processing tool, the manipulator 2 will be the next step to the need for the tool does not work on the tool spindle 3 until after the completion of this process , the first rotary turret 180 º, ATC completed. ATC most of their time and processing time coincidence, the only real tool change time turret transposition of the first time, this approach mainly used for ATC and NC NC drilling file bed. 2. 3.Daidao system for the automatic tool changeFigure 2.4 shows the knife and the whole machine tool CNC machine tools for the appearance of Fig.Figure 2.5 shows the knife and split-type machine to the appearance of CNC machine tool plans.At this point, knife storage capacity, a heavier tool can, and often additional transport unit to complete the knife between the spindle and cutting tool transport.Daidao the knife from the ATC, the election knives, automatic loading and unloading machine tool and tool exchange institutions (manipulator), composed of four parts, used widely.Tool Automatic Tool Change the manipulator system, the whole process more complicated ATC. We must first used in the processing of all installed in the standard tool on the knife handle in the machine outside the pre-size, according to a certain way Add to the knife. ATC, selected first in the knife knife, and then from ATC, from the knife from the knife or spindle, exchange, the new knife into the spindle, the old knife back into the knife.ATC, as the former two knives to accommodate a limited number can not be too many, can notmeet the needs of complex parts machining, CNC machine tool Automatic Tool Change Daidao the use of the automatic tool change devices. The knife has more capacity, both installed in the spindle box side or above. As for the automatic tool change Daidao device CNC machine tool spindle box only a spindle, spindle components to high stiffness to meet the machining requirements. The number of establishments in larger knife, which can meet the more complex parts of the machining processes, significantly improving productivity. Daidao system for the automatic tool change applied to drilling centres and CNC machining centers. The comparison drawn Daidao automatic tool change system is the most promising.3.PLC control of the knife random mode of election3. 1Common methods of automatic election knifeAutomatic control of the knife CNC refers to the system after the implementation of user instructions on the knife library automation process, including the process to find knives and automatic tool change [(63,71]. CNC Machining Center device (CNC) directive issued by the election knife , a knife, the tool required to take the knife position, said the election automatic knife. automatically elected knife There are two ways: random sequence election knives and knife election method.3.1.1 order election knifeTool Selection order is the process tool according to the sequence of the insert knife, the use of knives in order to take place, used knives back at the original knife, can also order Add Block, a knife. In this way, no need Tool identification devices, and drive control is a relatively simple, reliable and can be used directly from the points of the knife machinery to achieve. But the knives in each of the tool in different processes can not be reused, if the tool is installed in accordance with the order of the knife, there will be serious consequences. The need to increase the number of knives and knife the capacity of the tool and reduce the utilization of the knife. 3.1.2Random election knifeRandom election under the knife is arbitrary instructions to select the required tools, then there must be tool identification devices. Tool knife in the library do not have the processing in accordance with the order of the workpiece can be arbitrary storage. Each of the tool (or knifeblocks) are for a code, automatic tool change, the rotary cutter, every tool have been the "tool identification device" acceptable identification. When CNC tool code and the code in line with directives of the tool selected, the rotary cutter knives will be sent to the ATC position, waiting to grab manipulator. Random knife election is the advantage of the cutter knife in the order has nothing to do with the processing sequence, the same tool can be used repeatedly. Therefore, the relatively small number of knives, knife the corresponding smaller. Random elections knife on the tool must be coded to identify. There are three main coding.1. Tool coding. Adopt special knife handle structure coding, the drawbars on the knife handle back-end packages such as spacing of the coding part of the lock-nut fixed. Coding diameter ring diameter of a size two, respectively, said that binary "1" and "0" to the two rings are different, can be a series of code. For example, there are six small diameter of the ring can be made to distinguish between 63 (26-1 = 63) of the coding tool. All of 0 normally not allowed to use the code, to avoid the cutter knife Block did not confuse the situation.2. Knife Block coding. On the knife Block coding, coding tool, and tool into line with the number of knives in the Block. ATC knife when the rotation, so that each knife seats followed through knowledge knife, knife found blocks, knives stopped the rotation. At this time there is no knife handle encoding part of the knife handle simplified.3. Annex coding methods. This style of coding keys, coded cards, coding and coding-disc, which is the most widely used coding keys.First to knives are attached to a tool of the show wrapped coding keys, and when the cutter knife to the store at knife in, so put the number of keys to remember knife Block Road, will be inserted into key to the coding Block next to the key hole in the seat for the knife to the numbers.ConclusionFocused on in today's manufacturing environment tool storage and management of new models and methods, practical application of good results in systems integration and optimization, and other aspects of operations will be further explored, so that it has a higher theoretical and practical level.译文：机床刀具设计课题研究意义机床原来的刀库控制程序是单独设计的，没有采用刀具管理系统，功能也比较单一，只实现了刀库刀具的找刀、刀库最短路径定位、主轴换刀，而且不支持大型刀具。

机械类外文文献翻译(中英文翻译)英文原文Mechanical Design and Manufacturing ProcessesMechanical design is the application of science and technology to devise new or improved products for the purpose of satisfying human needs. It is a vast field of engineering technology which not only concerns itself with the original conception of the product in terms of its size, shape and construction details, but also considers the various factors involved in the manufacture, marketing and use of the product.People who perform the various functions of mechanical design are typically called designers, or design engineers. Mechanical design is basically a creative activity. However, in addition to being innovative, a design engineer must also have a solid background in the areas of mechanical drawing, kinematics, dynamics, materials engineering, strength of materials and manufacturing processes.As stated previously, the purpose of mechanical design is to produce a product which will serve a need for man. Inventions, discoveries and scientific knowledge by themselves do not necessarily benefit people; only if they are incorporated into a designed product will a benefit be derived. It should be recognized, therefore, that a human need must be identified before a particular product is designed.Mechanical design should be considered to be an opportunity to use innovative talents to envision a design of a product, to analyze the systemand then make sound judgments on how the product is to be manufactured. It is important to understand the fundamentals of engineering rather than memorize mere facts and equations. There are no facts or equations which alone can be used to provide all the correct decisions required to produce a good design.On the other hand, any calculations made must be done with the utmost care and precision. For example, if a decimal point is misplaced, an otherwise acceptable design may not function.Good designs require trying new ideas and being willing to take a certain amount of risk, knowing that if the new idea does not work the existing method can be reinstated. Thus a designer must have patience, since there is no assurance of success for the time and effort expended. Creating a completely new design generally requires that many old and well-established methods be thrust aside. This is not easy since many people cling to familiar ideas, techniques and attitudes. A design engineer should constantly search for ways to improve an existing product and must decide what old, proven concepts should be used and what new, untried ideas should be incorporated.New designs generally have "bugs" or unforeseen problems which must be worked out before the superior characteristics of the new designs can be enjoyed. Thus there is a chance for a superior product, but only at higher risk. It should be emphasized that, if a design does not warrant radical new methods, such methods should not be applied merely for the sake of change.During the beginning stages of design, creativity should be allowedto flourish without a great number of constraints. Even though many impractical ideas may arise, it is usually easy to eliminate them in the early stages of design before firm details are required by manufacturing. In this way, innovative ideas are not inhibited. Quite often, more than one design is developed, up to the point where they can be compared against each other. It is entirely possible that the design which is ultimately accepted will use ideas existing in one of the rejected designs that did not show as much overall promise.Psychologists frequently talk about trying to fit people to the machines they operate. It is essentially the responsibility of the design engineer to strive to fit machines to people. This is not an easy task, since there is really no average person for which certain operating dimensions and procedures are optimum.Another important point which should be recognized is that a design engineer must be able to communicate ideas to other people if they are to be incorporated. Communicating the design to others is the final, vital step in the design process. Undoubtedly many great designs, inventions, and creative works have been lost to mankind simply because the originators were unable or unwilling to explain their accomplishments to others. Presentation is a selling job. The engineer, when presenting a new solution to administrative, management, or supervisory persons, is attempting to sell or to prove to them that this solution is a better one. Unless this can be done successfully, the time and effort spent on obtaining the solution have been largely wasted.Basically, there are only three means of communication available tous. These are the written, the oral, and the graphical forms. Therefore the successful engineer will be technically competent and versatile in all three forms of communication. A technically competent person who lacks ability in any one of these forms is severely handicapped. If ability in all three forms is lacking, no one will ever know how competent that person is!The competent engineer should not be afraid of the possibility of not succeeding in a presentation. In fact, occasional failure should be expected because failure or criticism seems to accompany every really creative idea. There is a great deal to be learned from a failure, and the greatest gains are obtained by those willing to risk defeat. In the final analysis, the real failure would lie in deciding not to make the presentation at all. To communicate effectively, the following questions must be answered:(1) Does the design really serve a human need?(2) Will it be competitive with existing products of rival companies?(3) Is it economical to produce?(4) Can it be readily maintained?(5) Will it sell and make a profit?Only time will provide the true answers to the preceding questions, but the product should be designed, manufactured and marketed only with initial affirmative answers. The design engineer also must communicate the finalized design to manufacturing through the use of detail and assembly drawings.Quite often, a problem will occur during the manufacturing cycle [3].It may be that a change is required in the dimensioning or tolerancing of a part so that it can be more readily produced. This fails in the category of engineering changes which must be approved by the design engineer so that the product function will not be adversely affected. In other cases, a deficiency in the design may appear during assembly or testing just prior to shipping. These realities simply bear out the fact that design is a living process. There is always a better way to do it and the designer should constantly strive towards finding that better way.Designing starts with a need, real or imagined. Existing apparatus may need improvements in durability, efficiently, weight, speed, or cost. New apparatus may be needed to perform a function previously done by men, such as computation, assembly, or servicing. With the objective wholly or partly defined, the next step in design is the conception of mechanisms and their arrangements that will perform the needed functions.For this, freehand sketching is of great value, not only as a record of one's thoughts and as an aid in discussion with others, but particularly for communication with one's own mind, as a stimulant for creative ideas.When the general shape and a few dimensions of the several components become apparent, analysis can begin in earnest. The analysis will have as its objective satisfactory or superior performance, plus safety and durability with minimum weight, and a competitive east. Optimum proportions and dimensions will be sought for each critically loaded section, together with a balance between the strength of the several components. Materials and their treatment will be chosen. These important objectives can be attained only by analysis based upon the principles ofmechanics, such as those of statics for reaction forces and for the optimumutilization of friction; of dynamics for inertia, acceleration, and energy; of elasticity and strength of materials for stress。

中国地质大学长城学院本科毕业设计外文资料翻译系别：工程技术系专业：机械设计制造及其自动化姓名：侯亮学号：052115072015年 4 月 3 日外文资料翻译原文Introduction of MachiningHave a shape as a processing method, all machining process for the production of the most commonly used and most important method. Machining process is a process generated shape, in this process, Drivers device on the work piece material to be in the form of chip removal. Although in some occasions, the workpiece under no circumstances, the use of mobile equipment to the processing, However, the majority of the machining is not only supporting the workpiece also supporting tools and equipment to complete.Machining know the process has two aspects. Small group of low-cost production. For casting, forging and machining pressure, every production of a specific shape of the workpiece, even a spare parts, almost have to spend the high cost of processing. Welding to rely on the shape of the structure, to a large extent, depend on effective in the form of raw materials. In general, through the use of expensive equipment and without special processing conditions, can be almost any type of raw materials, mechanical processing to convert the raw materials processed into the arbitrary shape of the structure, as long as the external dimensions large enough, it is possible. Because of a production of spare parts, even when the parts and structure of the production batch sizes are suitable for the original casting, Forging or pressure processing to produce, but usually prefer machining.Strict precision and good surface finish, machining the second purpose is the establishment of the high precision and surface finish possible on the basis of. Many parts, if any other means of production belonging to the large-scale production, Well Machining is a low-tolerance and can meet the requirements of small batch production. Besides, many parts on the production and processing of coarse process to improve its general shape of the surface. It is only necessary precision and choose only the surface machining. For instance, thread, in addition to mechanical processing, almost no other processing method for processing. Another example is the blacksmith pieces keyhole processing, as well as training to be conducted immediately after the mechanical completion of the processing.Primary Cutting ParametersCutting the work piece and tool based on the basic relationship between the following four elements to fully describe : the tool geometry, cutting speed, feed rate, depth and penetration of a cutting tool.Cutting Tools must be of a suitable material to manufacture, it must be strong, tough, hard and wear-resistant. Tool geometry -- to the tip plane and cutter angle characteristics -- for each cutting process must be correct.Cutting speed is the cutting edge of work piece surface rate, it is inches per minute toshow. In order to effectively processing, and cutting speed must adapt to the level of specific parts -- with knives. Generally, the more hard work piece material, the lower the rate.Progressive Tool to speed is cut into the work piece speed. If the work piece or tool for rotating movement, feed rate per round over the number of inches to the measurement. When the work piece or tool for reciprocating movement and feed rate on each trip through the measurement of inches. Generally, in other conditions, feed rate and cutting speed is inversely proportional to.Depth of penetration of a cutting tool -- to inches dollars -- is the tool to the work piece distance. Rotary cutting it to the chip or equal to the width of the linear cutting chip thickness. Rough than finishing, deeper penetration of a cutting tool depth.Rough machining and finishing machiningThere are two kinds of cuts in machine- shop work called, respectively, the "roughing cut" and the "finishing cut". When a piece is "roughed out", it is quite near the shape and size required, but enough metal has been left on the surface to finish smooth and to exact size." Generally speaking, bars of steel, forging, castings, etc. are machined to the required shape and size with only one roughing and one finishing cut. Sometimes, however, certain portions of a piece may require more than one roughing cut. Also, in some jobs, for example, when great accuracy is not needed, or when a comparatively small amount of metal must be removed, a finishing cut may be all that is required. The roughing cut, to remove the greater part of the excess material, should be reasonably heavy, that is, all the machine, or cutting tool, or work, or all three, will stand. So the machinist’s purpose is to remove the excess stock as fast as he can without leaving, at the same time, a surface too torn and rough, without bending the piece if it is slender, and without spoiling the centers. The finishing cut, to make the work smooth and accurate, is a finer cut. The emphasis here is refinement - very sharp tool, comparatively little metal removed, and a higher degree of accuracy in measurement. Whether roughing or finishing, the machinist must set the machine for the given job. He must consider the size and shape of the work and the kind of material, also the kind of tool used and the nature of the cut to be made, then he proceeds to set the machine for the correct speed and feed and to set the tool to take the depth of cut desired.Automatic Fixture Design外文资料翻译译文机械制造工艺机械加工是所有制造过程中最普遍使用的而且是最重要的方法。

英文原文Basic Machining Operations and Cutting TechnologyBasic Machining OperationsMachine tools have evolved from the early foot-powered lathes of the Egyptians and John Wilkinson's boring mill. They are designed to provide rigid support for both the workpiece and the cutting tool and can precisely control their relative positions and the velocity of the tool with respect to the workpiece. Basically, in metal cutting, a sharpened wedge-shaped tool removes a rather narrow strip of metal from the surface of a ductile workpiece in the form of a severely deformed chip. The chip is a waste product that is considerably shorter than the workpiece from which it came but with a corresponding increase in thickness of the uncut chip. The geometrical shape of workpiece depends on the shape of the tool and its path during the machining operation.Most machining operations produce parts of differing geometry. If a rough cylindrical workpiece revolves about a central axis and the tool penetrates beneath its surface and travels parallel to the center of rotation, a surface of revolution is produced, and the operation is called turning. If a hollow tube is machined on the inside in a similar manner, the operation is called boring. Producing an external conical surface uniformly varying diameter is called taper turning, if the tool point travels in a path of varying radius, a contoured surface like that of a bowling pin can be produced; or, if the piece is short enough and the support is sufficiently rigid, a contoured surface could be produced by feeding a shaped tool normal to the axis of rotation. Short tapered or cylindrical surfaces could also be contour formed.Flat or plane surfaces are frequently required. They can be generated by radial turning or facing, in which the tool point moves normal to the axis of rotation. In other cases, it is more convenient to hold the workpiece steady and reciprocate the tool across it in a series of straight-line cuts with a crosswise feed increment before each cutting stroke. This operation is called planning and is carried out on a shaper. For larger pieces it is easier to keep the tool stationary and draw the workpiece under it as in planning. The tool is fed at each reciprocation. Contoured surfaces can be produced by using shaped tools.Multiple-edged tools can also be used. Drilling uses a twin-edged fluted tool for holes with depths up to 5 to 10 times the drill diameter. Whether thedrill turns or the workpiece rotates, relative motion between the cutting edge and the workpiece is the important factor. In milling operations a rotary cutter with a number of cutting edges engages the workpiece. Which moves slowly with respect to the cutter. Plane or contoured surfaces may be produced, depending on the geometry of the cutter and the type of feed.Horizontal or vertical axes of rotation may be used, and the feed of the workpiece may be in any of the three coordinate directions.Basic Machine ToolsMachine tools are used to produce a part of a specified geometrical shape and precise I size by removing metal from a ductile material in the form of chips. The latter are a waste product and vary from long continuous ribbons of a ductile material such as steel, which are undesirable from a disposal point of view, to easily handled well-broken chips resulting from cast iron. Machine tools perform five basic metal-removal processes: I turning, planning, drilling, milling, and grinding. All other metal-removal processes are modifications of these five basic processes. For example, boring is internal turning; reaming, tapping, and counter boring modify drilled holes and are related to drilling; bobbing and gear cutting are fundamentally milling operations; hack sawing and broaching are a form of planning and honing; lapping, super finishing. Polishing and buffing are variants of grinding or abrasive removal operations. Therefore, there are only four types of basic machine tools, which use cutting tools of specific controllable geometry: 1. lathes, 2. planers, 3. drilling machines, and 4. milling machines. The grinding process forms chips, but the geometry of the abrasive grain is uncontrollable.The amount and rate of material removed by the various machining processes may be I large, as in heavy turning operations, or extremely small, as in lapping or super finishing operations where only the high spots of a surface are removed.A machine tool performs three major functions: 1. it rigidly supports the workpiece or its holder and the cutting tool; 2. it provides relative motion between the workpiece and the cutting tool; 3. it provides a range of feeds and speeds usually ranging from 4 to 32 choices in each case.Speed and Feeds in MachiningSpeeds, feeds, and depth of cut are the three major variables for economical machining. Other variables are the work and tool materials, coolant and geometry of the cutting tool. The rate of metal removal and power required for machining depend upon these variables.The depth of cut, feed, and cutting speed are machine settings that must be established in any metal-cutting operation. They all affect the forces, the power, and the rate of metal removal. They can be defined by comparing them to the needle and record of a phonograph. The cutting speed (V) is represented by the velocity of- the record surface relative to the needle in the tone arm at any instant. Feed is represented by the advance of the needle radially inward per revolution, or is the difference in position between two adjacent grooves. The depth of cut is the penetration of the needle into the record or the depth of the grooves.Turning on Lathe CentersThe basic operations performed on an engine lathe are illustrated. Those operations performed on external surfaces with a single point cutting tool are called turning. Except for drilling, reaming, and lapping, the operations on internal surfaces are also performed by a single point cutting tool.All machining operations, including turning and boring, can be classified as roughing, finishing, or semi-finishing. The objective of a roughing operation is to remove the bulk of the material as rapidly and as efficiently as possible, while leaving a small amount of material on the work-piece for the finishing operation. Finishing operations are performed to obtain the final size, shape, and surface finish on the workpiece. Sometimes a semi-finishing operation will precede the finishing operation to leave a small predetermined and uniform amount of stock on the work-piece to be removed by the finishing operation.Generally, longer workpieces are turned while supported on one or two lathe centers. Cone shaped holes, called center holes, which fit the lathe centers are drilled in the ends of the workpiece-usually along the axis of the cylindrical part. The end of the workpiece adjacent to the tailstock is always supported by a tailstock center, while the end near the headstock may be supported by a headstock center or held in a chuck. The headstock end of the workpiece may be held in a four-jaw chuck, or in a type chuck. This method holds the workpiece firmly and transfers the power to the workpiece smoothly; the additional support to the workpiece provided by the chuck lessens the tendency for chatter to occur when cutting. Precise results can be obtained with this method if care is taken to hold the workpiece accurately in the chuck.Very precise results can be obtained by supporting the workpiece between two centers. A lathe dog is clamped to the workpiece; together they are driven by a driver plate mounted on the spindle nose. One end of the Workpiece is mecained;then the workpiece can be turned around in the lathe to machine the other end. The center holes in the workpiece serve as precise locating surfaces as well as bearing surfaces to carry the weight of the workpiece and to resist the cutting forces. After the workpiece has been removed from the lathe for any reason, the center holes will accurately align the workpiece back in the lathe or in another lathe, or in a cylindrical grinding machine. The workpiece must never be held at the headstock end by both a chuck and a lathe center. While at first thought this seems like a quick method of aligning the workpiece in the chuck, this must not be done because it is not possible to press evenly with the jaws against the workpiece while it is also supported by the center. The alignment provided by the center will not be maintained and the pressure of the jaws may damage the center hole, the lathe center, and perhaps even the lathe spindle. Compensating or floating jaw chucks used almost exclusively on high production work provide an exception to the statements made above. These chucks arereally work drivers and cannot be used for the same purpose as ordinary three or four-jaw chucks.While very large diameter workpieces are sometimes mounted on two centers, they are preferably held at the headstock end by faceplate jaws to obtain the smooth power transmission; moreover, large lathe dogs that are adequate to transmit the power not generally available, although they can be made as a special. Faceplate jaws are like chuck jaws except that they are mounted on a faceplate, which has less overhang from the spindle bearings than a large chuck would have.Introduction of MachiningMachining as a shape-producing method is the most universally used and the most important of all manufacturing processes. Machining is a shape-producing process in which a power-driven device causes material to be removed in chip form. Most machining is done with equipment that supports both the work piece and cutting tool although in some cases portable equipment is used with unsupported workpiece.Low setup cost for small Quantities. Machining has two applications in manufacturing. For casting, forging, and press working, each specific shape to be produced, even one part, nearly always has a high tooling cost. The shapes that may he produced by welding depend to a large degree on the shapes of raw material that are available. By making use of generally high cost equipment but without special tooling, it is possible, by machining; to start with nearly any form of raw material, so tong as the exterior dimensions are great enough, and produce any desired shape from any material. Therefore .machining is usually the preferred method for producing one or a few parts, even when the design of the part would logically lead to casting, forging or press working if a high quantity were to be produced.Close accuracies, good finishes. The second application for machining is based on the high accuracies and surface finishes possible. Many of the parts machined in low quantities would be produced with lower but acceptable tolerances if produced in high quantities by some other process. On the other hand, many parts are given their general shapes by some high quantity deformation process and machined only on selected surfaces where high accuracies are needed. Internal threads, for example, are seldom produced by any means other than machining and small holes in press worked parts may be machined following the press working operations.Primary Cutting ParametersThe basic tool-work relationship in cutting is adequately described by means of four factors: tool geometry, cutting speed, feed, and depth of cut.The cutting tool must be made of an appropriate material; it must be strong, tough, hard, and wear resistant. The tool s geometry characterized by planes and angles, must be correct foreach cutting operation. Cutting speed is the rate at which the work surface passes by the cutting edge. It may be expressed in feet per minute.For efficient machining the cutting speed must be of a magnitude appropriate to the particular work-tool combination. In general, the harder the work material, the slower the speed.Feed is the rate at which the cutting tool advances into the workpiece. "Where the workpiece or the tool rotates, feed is measured in inches per revolution. When the tool or the work reciprocates, feed is measured in inches per stroke, Generally, feed varies inversely with cutting speed for otherwise similar conditions.The depth of cut, measured inches is the distance the tool is set into the work. It is the width of the chip in turning or the thickness of the chip in a rectilinear cut. In roughing operations, the depth of cut can be larger than for finishing operations.The Effect of Changes in Cutting Parameters on Cutting TemperaturesIn metal cutting operations heat is generated in the primary and secondary deformation zones and these results in a complex temperature distribution throughout the tool, workpiece and chip. A typical set of isotherms is shown in figure where it can be seen that, as could be expected, there is a very large temperature gradient throughout the width of the chip as the workpiece material is sheared in primary deformation and there is a further large temperature in the chip adjacent to the face as the chip is sheared in secondary deformation. This leads to a maximum cutting temperature a short distance up the face from the cutting edge and a small distance into the chip.Since virtually all the work done in metal cutting is converted into heat, it could be expected that factors which increase the power consumed per unit volume of metal removed will increase the cutting temperature. Thus an increase in the rake angle, all other parameters remaining constant, will reduce the power per unit volume of metal removed and the cutting temperatures will reduce. When considering increase in unreformed chip thickness and cutting speed the situation is more complex. An increase in undeformed chip thickness tends to be a scale effect where the amounts of heat which pass to the workpiece, the tool and chip remain in fixed proportions and the changes in cutting temperature tend to be small. Increase in cutting speed; however, reduce the amount of heat which passes into the workpiece and this increase the temperature rise of the chip m primary deformation. Further, the secondary deformation zone tends to be smaller and this has the effect of increasing the temperatures in this zone. Other changes in cutting parameters have virtually no effect on the power consumed per unit volume of metal removed and consequently have virtually no effect on the cutting temperatures. Since it has been shown that even small changes in cutting temperature have a significant effect on tool wear rate it is appropriate to indicate how cutting temperatures can be assessed from cutting data.The most direct and accurate method for measuring temperatures in high -speed-steel cutting tools is that of Wright &. Trent which also yields detailed information on temperature distributions in high-speed-steel cutting tools. The technique is based on the metallographic examination of sectioned high-speed-steel tools which relates microstructure changes to thermal history.Trent has described measurements of cutting temperatures and temperature distributions for high-speed-steel tools when machining a wide range of workpiece materials. This technique has been further developed by using scanning electron microscopy to study fine-scale microstructure changes arising from over tempering of the tempered martens tic matrix of various high-speed-steels. This technique has also been used to study temperature distributions in both high-speed -steel single point turning tools and twist drills.Wears of Cutting ToolDiscounting brittle fracture and edge chipping, which have already been dealt with, tool wear is basically of three types. Flank wear, crater wear, and notch wear. Flank wear occurs on both the major and the minor cutting edges. On the major cutting edge, which is responsible for bulk metal removal, these results in increased cutting forces and higher temperatures which if left unchecked can lead to vibration of the tool and workpiece and a condition where efficient cutting can no longer take place. On the minor cutting edge, which determines workpiece size and surface finish, flank wear can result in an oversized product which has poor surface finish. Under most practical cutting conditions, the tool will fail due to major flank wear before the minor flank wear is sufficiently large to result in the manufacture of an unacceptable component.Because of the stress distribution on the tool face, the frictional stress in the region of sliding contact between the chip and the face is at a maximum at the start of the sliding contact region and is zero at the end. Thus abrasive wear takes place in this region with more wear taking place adjacent to the seizure region than adjacent to the point at which the chip loses contact with the face. This result in localized pitting of the tool face some distance up the face which is usually referred to as catering and which normally has a section in the form of a circular arc. In many respects and for practical cutting conditions, crater wear is a less severe form of wear than flank wear and consequently flank wear is a more common tool failure criterion. However, since various authors have shown that the temperature on the face increases more rapidly with increasing cutting speed than the temperature on the flank, and since the rate of wear of any type is significantly affected by changes in temperature, crater wear usually occurs at high cutting speeds.At the end of the major flank wear land where the tool is in contact with the uncut workpiece surface it is common for the flank wear to be more pronounced than along the rest ofthe wear land. This is because of localised effects such as a hardened layer on the uncut surface caused by work hardening introduced by a previous cut, an oxide scale, and localised high temperatures resulting from the edge effect. This localised wear is usually referred to as notch wear and occasionally is very severe. Although the presence of the notch will not significantly affect the cutting properties of the tool, the notch is often relatively deep and if cutting were to continue there would be a good chance that the tool would fracture.If any form of progressive wear allowed to continue, dramatically and the tool would fail catastrophically, i. e. the tool would be no longer capable of cutting and, at best, the workpiece would be scrapped whilst, at worst, damage could be caused to the machine tool. For carbide cutting tools and for all types of wear, the tool is said to have reached the end of its useful life long before the onset of catastrophic failure. For high-speed-steel cutting tools, however, where the wear tends to be non-uniform it has been found that the most meaningful and reproducible results can be obtained when the wear is allowed to continue to the onset of catastrophic failure even though, of course, in practice a cutting time far less than that to failure would be used. The onset of catastrophic failure is characterized by one of several phenomena, the most common being a sudden increase in cutting force, the presence of burnished rings on the workpiece, and a significant increase in the noise level.Mechanism of Surface Finish ProductionThere are basically five mechanisms which contribute to the production of a surface which have been machined. These are:(l) The basic geometry of the cutting process. In, for example, single point turning the tool will advance a constant distance axially per revolution of the workpiecc and the resultant surface will have on it, when viewed perpendicularly to the direction of tool feed motion, a series of cusps which will have a basic form which replicates the shape of the tool in cut.(2) The efficiency of the cutting operation. It has already been mentioned that cutting with unstable built-up-edges will produce a surface which contains hard built-up-edge fragments which will result in a degradation of the surface finish. It can also be demonstrated that cutting under adverse conditions such as apply when using large feeds small rake angles and low cutting speeds, besides producing conditions which lead to unstable built-up-edge production, the cutting process itself can become unstable and instead of continuous shear occurring in the shear zone, tearing takes place, discontinuous chips of uneven thickness are produced, and the resultant surface is poor. This situation is particularly noticeable when machining very ductile materials such as copper and aluminum.(3) The stability of the machine tool. Under some combinations of cutting conditions; workpiece size, method of clamping ,and cutting tool rigidity relative to the machine toolstructure, instability can be set up in the tool which causes it to vibrate. Under some conditions this vibration will reach and maintain steady amplitude whilst under other conditions the vibration will built up and unless cutting is stopped considerable damage to both the cutting tool and workpiece may occur. This phenomenon is known as chatter and in axial turning is characterized by long pitch helical bands on the workpiece surface and short pitch undulations on the transient machined surface.(4)The effectiveness of removing swarf. In discontinuous chip production machining, such as milling or turning of brittle materials, it is expected that the chip (swarf) will leave the cutting zone either under gravity or with the assistance of a jet of cutting fluid and that they will not influence the cut surface in any way. However, when continuous chip production is evident, unless steps are taken to control the swarf it is likely that it will impinge on the cut surface and mark it. Inevitably, this marking besides looking.(5)The effective clearance angle on the cutting tool. For certain geometries of minor cutting edge relief and clearance angles it is possible to cut on the major cutting edge and burnish on the minor cutting edge. This can produce a good surface finish but, of course, it is strictly a combination of metal cutting and metal forming and is not to be recommended as a practical cutting method. However, due to cutting tool wear, these conditions occasionally arise and lead to a marked change in the surface characteristics.Limits and TolerancesMachine parts are manufactured so they are interchangeable. In other words, each part of a machine or mechanism is made to a certain size and shape so will fit into any other machine or mechanism of the same type. To make the part interchangeable, each individual part must be made to a size that will fit the mating part in the correct way. It is not only impossible, but also impractical to make many parts to an exact size. This is because machines are not perfect, and the tools become worn. A slight variation from the exact size is always allowed. The amount of this variation depends on the kind of part being manufactured. For examples part might be made 6 in. long with a variation allowed of 0.003 (three-thousandths) in. above and below this size. Therefore, the part could be 5.997 to 6.003 in. and still be the correct size. These are known as the limits. The difference between upper and lower limits is called the tolerance.A tolerance is the total permissible variation in the size of a part.The basic size is that size from which limits of size arc derived by the application of allowances and tolerances.Sometimes the limit is allowed in only one direction. This is known as unilateral tolerance.Unilateral tolerancing is a system of dimensioning where the tolerance (that is variation) is shown in only one direction from the nominal size. Unilateral tolerancing allow the changing of tolerance on a hole or shaft without seriously affecting the fit.When the tolerance is in both directions from the basic size it is known as a bilateral tolerance (plus and minus).Bilateral tolerancing is a system of dimensioning where the tolerance (that is variation) is split and is shown on either side of the nominal size. Limit dimensioning is a system of dimensioning where only the maximum and minimum dimensions arc shown. Thus, the tolerance is the difference between these two dimensions.Surface Finishing and Dimensional ControlProducts that have been completed to their proper shape and size frequently require some type of surface finishing to enable them to satisfactorily fulfill their function. In some cases, it is necessary to improve the physical properties of the surface material for resistance to penetration or abrasion. In many manufacturing processes, the product surface is left with dirt .chips, grease, or other harmful material upon it. Assemblies that are made of different materials, or from the same materials processed in different manners, may require some special surface treatment to provide uniformity of appearance.Surface finishing may sometimes become an intermediate step processing. For instance, cleaning and polishing are usually essential before any kind of plating process. Some of the cleaning procedures are also used for improving surface smoothness on mating parts and for removing burrs and sharp corners, which might be harmful in later use. Another important need for surface finishing is for corrosion protection in a variety of: environments. The type of protection procedure will depend largely upon the anticipated exposure, with due consideration to the material being protected and the economic factors involved.Satisfying the above objectives necessitates the use of main surface-finishing methods that involve chemical change of the surface mechanical work affecting surface properties, cleaning by a variety of methods, and the application of protective coatings, organic and metallic.In the early days of engineering, the mating of parts was achieved by machining one part as nearly as possible to the required size, machining the mating part nearly to size, and then completing its machining, continually offering the other part to it, until the desired relationship was obtained. If it was inconvenient to offer one part to the other part during machining, the final work was done at the bench by a fitter, who scraped the mating parts until the desired fit was obtained, the fitter therefore being a 'fitter' in the literal sense. J It is obvious that the two parts would have to remain together, and m the event of one having to be replaced, the fitting would have to be done all over again. In these days, we expect to be able to purchase a replacement fora broken part, and for it to function correctly without the need for scraping and other fitting operations.When one part can be used 'off the shelf' to replace another of the same dimension and material specification, the parts are said to be interchangeable. A system of interchangeability usually lowers the production costs as there is no need for an expensive, 'fiddling' operation, and it benefits the customer in the event of the need to replace worn parts.Automatic Fixture DesignTraditional synchronous grippers for assembly equipment move parts to the gripper centre-line, assuring that the parts will be in a known position after they arc picked from a conveyor or nest. However, in some applications, forcing the part to the centre-line may damage cither the part or equipment. When the part is delicate and a small collision can result in scrap, when its location is fixed by a machine spindle or mould, or when tolerances are tight, it is preferable to make a gripper comply with the position of the part, rather than the other way around. For these tasks, Zaytran Inc. Of Elyria, Ohio, has created the GPN series of non- synchronous, compliant grippers. Because the force and synchronizations systems of the grippers are independent, the synchronization system can be replaced by a precision slide system without affecting gripper force. Gripper sizes range from 51b gripping force and 0.2 in. stroke to 40Glb gripping force and 6in stroke. GrippersProduction is characterized by batch-size becoming smaller and smaller and greater variety of products. Assembly, being the last production step, is particularly vulnerable to changes in schedules, batch-sizes, and product design. This situation is forcing many companies to put more effort into extensive rationalization and automation of assembly that was previouslyextensive rationalization and automation of assembly that was previously the case. Although the development of flexible fixtures fell quickly behind the development of flexible handling systems such as industrial robots, there are, nonetheless promising attempts to increase the flexibility of fixtures. The fact that fixtures are the essential product - specific investment of a production system intensifies the economic necessity to make the fixture system more flexible.Fixtures can be divided according to their flexibility into special fixtures, group fixtures, modular fixtures and highly flexible fixtures. Flexible fixtures are characterized by their high adaptability to different workpieces, and by low change-over time and expenditure.There are several steps required to generate a fixture, in which a workpiece is fixed for a production task. The first step is to define the necessary position of the workpiece in the fixture, based on the unmachined or base pan, and the working features. Following this, a combination of stability planes must be selected. These stability planes constitute the fixture configuration in which the workpiece is fixed in the defined position, all the forces or torques are compensated,。

Auto steering systemAbstract: With the rapid development of electronic technology, people on the vehicle steering control performance of more and more high. Wire control steering system will be the trend of the development of automobile steering system. Normally according to mechanical steering gear form can be divided into: super-modulus gear type, circulation ball type, worm wheel type, worm gear and worm refers to pin type. The increase of vehicle weight and people to the improvement of vehicle handling performance requirements, simple mechanical steering system can not meet needs, power steering system came into being, it can in the pilot turned the steering wheel and at the same time provide power, power steering system is divided into hydraulic steering system and electric steering system 2 kinds. Hydraulic steering system which is the most widely used steering system.Hydraulic steering system is the basis of the mechanical system increases the system, including hydraulic pump, v-shaped belt wheel, oil injection equipment, power devices and control valves. With the help of the automobile engine driving hydraulic pump, air compressor and generator etc, in order to hydraulic, pneumatic or electric power increases the power of the front wheel steering the pilot control to make drivers can light the flexibility to manipulate car turned, reduce labor intensity, improve the driving safety.Electric power steering system is now the development direction of car steering system, its working principle is: EPS system to the ECU from steering wheel torque sensor and speed sensor signal analysis, control motor to produce the proper power torque, assist drivers finish to the operation.Key words: Wire control steering system Hydraulic steering system Electric power steering system sensorAlong with automobile electronic technology swift and violent development, the people also day by day enhance to the motor turning handling quality request. The motor turning system changed, the hydraulic pressure boost from the traditional machinery changes (Hydraulic Power Steering, is called HPS), the electrically controlled hydraulicpressure boost changes (Elect ric Hydraulic Power Steering, is called EHPS), develops the electrically operated boost steering system (Elect ric Power Steering, is called EPS), finally also will transit to the line controls the steering system (Steer By Wire, will be called SBW).The machinery steering system is refers by pilot's physical strength achievement changes the energy, in which all power transmission all is mechanical, the automobile changes the movement is operates the steering wheel by the pilot, transmits through the diverter and a series of members changes the wheel to realize. The mechanical steering system by changes the control mechanism, the diverter and major part changes the gearing 3 to be composed.Usually may divide into according to the mechanical diverter form: The gear rack type, follows round the world -like, the worm bearing adjuster hoop type, the worm bearing adjuster refers sells the type. Is the gear rack type and follows using the broadest two kinds round the world -like (uses in needing time big steering force).In follows round the world -like in the diverter, the input changes the circle and the output steering arm pivot angle is proportional; In the gear rack type diverter, the input changes the turn and the output rack displacement is proportional. Follows round the world -like the diverter because is the rolling friction form, thus the transmission efficiency is very high, the ease of operation also the service life are long, moreover bearing capacity, therefore widely applies on the truck. The gear rack type diverter with follows round the world -like compares, the most major characteristic is the rigidity is big, the structure compact weight is light, also the cost is low. Because this way passes on easily by the wheel the reacting force to the steering wheel, therefore has to the pavement behavior response keen merit, but simultaneously also easy to have phenomena and so on goon and oscillation, also its load bearing efficiency relative weak, therefore mainly applies on the compact car and the pickup truck, at present the majority of low end passenger vehicle uses is the gear rack type machinery steering system.Along with the vehicles carrying capacity increase as well as the people to the vehicles handling quality request enhancement, the simple mechanical type steering systemwere already unable to meet the needs, the power steering system arise at the historic moment, it could rotate the steering wheel while the pilot to provide the boost, the power steering system divides into the hydraulic pressure steering system and the electrically operated steering system two kinds.Hydraulic pressure steering system is at present uses the most widespread steering system.The hydraulic pressure steering system increased the hydraulic system in the mechanical system foundation, including hydraulic pump, V shape band pulley, drill tubing, feed installment, boost installment and control valve. It with the aid of in the motor car engine power actuation hydraulic pump, the air compressor and the generator and so on, by the fluid strength, the physical strength or the electric power increases the pilot to operate the strength which the front wheel changes, enables the pilot to be possible nimbly to operate motor turning facilely, reduced the labor intensity, enhanced the travel security.The hydraulic pressure boost steering system from invented already had about half century history to the present, might say was one kind of more perfect system, because its work reliable, the technology mature still widely is applied until now. It takes the power supply by the hydraulic pump, after oil pipe-line control valves to power hydraulic cylinder feed, through the connecting rod impetus rotation gear movement, may changes the boost through the change cylinder bore and the flowing tubing head pressure size the size, from this achieved changes the boost the function. The traditional hydraulic pressure type power steering system may divide into generally according to the liquid flow form: Ordinary flow type and atmospheric pressure type 2 kind of types, also may divide into according to the control valve form transfers the valve type and the slide-valve type.Along with hydraulic pressure power steering system on automobile daily popularization, the people to operates when the portability and the road feeling request also day by day enhance, however the hydraulic pressure power steering system has many shortcomings actually: ①Because its itself structure had decided it is unable to guarantee vehicles rotates the steering wheel when any operating mode, all has the ideal operation stability, namely is unable simultaneously to guarantee time the low speed changes the portability and the high speed time operation stability; ②The automobile changes thecharacteristic to drive the pilot technical the influence to be serious; ③The steering ratio is fixed, causes the motor turning response characteristic along with changes and so on vehicle speed, transverse acceleration to change, the pilot must aim at the motor turning characteristic peak-to-peak value and the phase change ahead of time carries on certain operation compensation, thus controls the automobile according to its wish travel. Like this increased pilot's operation burden, also causes in the motor turning travel not to have the security hidden danger; But hereafter appeared the electrically controlled hydraulic booster system, it increases the velocity generator in the traditional hydraulic pressure power steering system foundation, enables the automobile along with the vehicle speed change automatic control force size, has to a certain extent relaxed the traditional hydraulic pressure steering system existence question.At present our country produces on the commercial vehicle and the passenger vehicle uses mostly is the electrically controlled hydraulic pressure boost steering system, it is quite mature and the application widespread steering system. Although the electrically controlled hydraulic servo alleviated the traditional hydraulic pressure from certain degree to change between the portability and the road feeling contradiction, however it did not have fundamentally to solve the HPS system existence insufficiency, along with automobile microelectronic technology development, automobile fuel oil energy conservation request as well as global initiative environmental protection, it in aspect and so on arrangement, installment, leak-proof quality, control sensitivity, energy consumption, attrition and noise insufficiencies already more and more obvious, the steering system turned towards the electrically operated boost steering system development.The electrically operated boost steering system is the present motor turning system development direction, its principle of work is: EPS system ECU after comes from the steering wheel torque sensor and the vehicle speed sensor signal carries on analysis processing, controls the electrical machinery to have the suitable boost torque, assists the pilot to complete changes the operation. In the last few years, along with the electronic technology development, reduces EPS the cost to become large scale possibly, Japan sends the car company, Mitsubishi Car company, this field car company, US's Delphi automobilesystem company, TRW Corporation and Germany's ZF Corporation greatly all one after another develops EPS.Mercedes2Benz and Siemens Automotive Two big companies invested 65,000,000 pounds to use in developing EPS, the goal are together load a car to 2002, yearly produce 300 ten thousand sets, became the global EPS manufacturer. So far, the EPS system in the slight passenger vehicle, on the theater box type vehicle obtains the widespread application, and every year by 300 ten thousand speed development.Steering is the term applied to the collection of components, linkages, etc. which allow for a vessel (ship, boat) or vehicle (car) to follow the desired course. An exception is the case of rail transport by which rail tracks combined together with railroad switches provide the steering function.The most conventional steering arrangement is to turn the front wheels using ahand–operated steering wheel which is positioned in front of the driver, via the steering column, which may contain universal joints to allow it to deviate somewhat from a straight line. Other arrangements are sometimes found on different types of vehicles, for example, a tiller or rear–wheel steering. Tracked vehicles such as tanks usually employ differential steering — that is, the tracks are made to move at different speeds or even in opposite directions to bring about a change of course.Many modern cars use rack and pinion steering mechanisms, where the steering wheel turns the pinion gear; the pinion moves the rack, which is a sort of linear gear which meshes with the pinion, from side to side. This motion applies steering torque to the kingpins of the steered wheels via tie rods and a short lever arm called the steering arm.Older designs often use the recirculating ball mechanism, which is still found on trucks and utility vehicles. This is a variation on the older worm and sector design; the steering column turns a large screw (the "worm gear") which meshes with a sector of a gear, causing it to rotate about its axis as the worm gear is turned; an arm attached to the axis of the sector moves the pitman arm, which is connected to the steering linkage and thus steers the wheels. The recalculating ball version of this apparatus reduces the considerable friction by placing large ball bearings between the teeth o f the worm and those of the screw; at either end of the apparatus the balls exit from between the two piecesinto a channel internal to the box which connects them with the other end of the apparatus, thus they are "recirculated".The rack and pinion design has the advantages of a large degree of feedback and direct steering "feel"; it also does not normally have any backlash, or slack. A disadvantage is that it is not adjustable, so that when it does wear and develop lash, the only cure is replacement.The recirculating ball mechanism has the advantage of a much greater mechanical advantage, so that it was found on larger, heavier vehicles while the rack and pinion was originally limited to smaller and lighter ones; due to the almost universal adoption of power steering, however, this is no longer an important advantage, leading to the increasing use of rack and pinion on newer cars. The recirculating ball design also has a perceptible lash, or "dead spot" on center, where a minute turn of the steering wheel in either direction does not move the steering apparatus; this is easily adjustable via a screw on the end of the steering box to account for wear, but it cannot be entirely eliminated or the mechanism begins to wear very rapidly. This design is still in use in trucks and other large vehicles, where rapidity of steering and direct feel are less important than robustness, maintainability, and mechanical advantage. The much smaller degree of feedback with this design can also sometimes be an advantage; drivers of vehicles with rack and pinion steering can have their thumbs broken when a front wheel hits a bump, causing the steering wheel to kick to one side suddenly (leading to driving instructors telling students to keep their thumbs on the front of the steering wheel, rather than wrapping around the inside of the rim). This effect is even stronger with a heavy vehicle like a truck; recirculating ball steering prevents this degree of feedback, just as it prevents desirable feedback under normal circumstances.The steering linkage connecting the steering box and the wheels usually conforms to a variation of Ackermann steering geometry, to account for the fact that in a turn, the inner wheel is actually traveling a path of smaller radius than the outer wheel, so that the degree of toe suitable for driving in a straight path is not suitable for turns.As vehicles have become heavier and switched to front wheel drive, the effort to turn the steering wheel manually has increased - often to the point where major physical exertion is required. To alleviate this, auto makers have developed power steering systems. There are two types of power steering systems—hydraulic and electric/electronic. There is also a hydraulic-electric hybrid system possible.A hydraulic power steering (HPS) uses hydraulic pressure supplied by anengine-driven pump to assist the motion of turning the steering wheel. Electric power steering (EPS) is more efficient than the hydraulic power steering, since the electric power steering motor only needs to provide assist when the steering wheel is turned, whereas the hydraulic pump must run constantly. In EPS the assist level is easily tunable to the vehicle type, road speed, and even driver preference. An added benefit is the elimination of environmental hazard posed by leakage and disposal of hydraulic power steering fluid.An outgrowth of power steering is speed adjustable steering, where the steering is heavily assisted at low speed and lightly assisted at high speed. The auto makers perceive that motorists might need to make large steering inputs while manoeuvering for parking, but not while traveling at high speed. The first vehicle with this feature was the Citroën SM with its Diravi layout, although rather than altering the amount of assistance as in modern power steering systems, it altered the pressure on a centring cam which made the steering wheel try to "spring" back to the straight-ahead position. Modern speed-adjustable power steering systems reduce the pressure fed to the ram as the speed increases, giving a more direct feel. This feature is gradually becoming commonplace across all new vehicles.汽车转向系统摘要：随着汽车电子技术的快速发展，人们对汽车转向的操纵性能越来越高。