齿轮的加工方法毕业课程设计外文文献翻译

Gears are vital factors in machinery. One of the first mechanism invented using gears was the clocks. In fact, a clock is little more than a train of study and research have been made on gears in recent years because of their wide use under exacting conditions. They have to transmit heavier loads and run at higher speeds than ever before. The engineers and the machinists all consider gearing the prime elementin nearly all classes of machinery.齿轮在机械中占有极为重要的作用。

第一个利用齿轮做成的机械装置确实是钟表，事实上，它只只是是用了一系列的齿轮。

关于它能够在严格的条件下的普遍利用，在齿轮上做了大量的学习和研究。

相较过去，它们此刻必需在更高的速度下传递更重的负荷。

工程师和机械操纵工人都以为齿轮在几乎所有的机械的零件中占有首要的因素。

1. Spur gearsSpur gears are used to transmit power and rotary motion between parallel shafts. The teeth are cut parallel to the axis of the shaft on which the gears are mounted. The smaller of two gears in mesh is called the pinion and the larger is customarily Designated as the gear. In most applications, the pinion is the driving element whereas the gear is the driven element.1.直齿圆柱齿轮直齿圆柱齿轮用于平行轴之间传递力和回转运动，轮齿被切制成与安装齿轮的轴之轴线相平行。

毕业设计中英文翻译英文原文Hard gear processing[abstract ]uses in the power drive gear and the gear box, its size request smaller, the gear drive noise is lower, thus causes to the hard gear demand, also gave the gear manufacturer to propose explored the gear to process the new method the request OutlineUses in the power drive gear and the gear box, its size request smaller, the gear drive noise is lower, thus causes to the hard gear demand, also gave the gear manufacturer to propose explored the gear to process the new method the request. The gear in the hard heat treatment process, its material organization and the stress change, usually can cause the gear to have the distortion, namely tooth profile, tooth to and tooth pitch error. This this error will cause the tooth profile not correctly to mesh in the transmission time, thus has enlarged the load, will have the gear noise. Therefore, the hard gear after the heat treatment, should increase together the precision work working procedure generally.The hard gear precision work craft may divide into two kinds: A kind is uses non- formed the cutting edge, like the gear rubs truncates the processing; Another kind then is has formed the cutting edge like hard gear (HRC48 ~ 53) to roll truncates the processing.This article strongly will discuss will use in hardly rolling the hard alloy tools forming cutting edge precision work process which the tooth will process. The now hard alloy material, the cutting tool coating and the gear-hobbing machine technology development, has caused the hard gear to roll cuts the processing technology to have the remarkable enhancement, specially is smaller than in the processing or was equal to when 12DP center small modulus gear, may withstand the enormous cutting force which in the hard cutting process produces.Hard alloy hob selectionThe hard alloy hob has the very big progress in the material variety specification. Superfine, is thin, medium or the big pellet hard alloy now all has the product. In addition, the hard alloy hob semifinished materials formed craft technology also had the remarkable enhancement, like uses static pressure and so on heat (HIP) the craft, this craft under the high-pressured high temperature, increased the hard alloy semifinished materials intrinsic binding force, enhanced the hard alloy anti- curved intensity. According to the ISO stipulation, the entity hard alloy material may differently divide into certain kinds according to the application situation: The gear cutting tool divides into K kind and P kind, K kind of hard alloy has a higherresistance to wear, P kind then has the better high temperature red hardness. In the K trademark and in the P trademark hard alloy, each kind of trademark hard alloy granular structure is different, from medium pellet to superfine pellet. Each kind of trademark all has its application situation, this is and the granular structure is connected. Generally speaking, regarding softly rolls truncates, the K analogy P kind of performance is friends with, K kind of hard alloy can obtain a micron level the granular structure (granularity to be smaller than 0.5 mu m), but P kind then is not good. In abrasion aspect, K kind of toughness better, the life is longer.The hob resharpens and renovatesAfter the hob processing certain quantity work piece, its cutting edge failure, this time must resharpen. Sharpens the after hob to have to maintain the original geometry shape; The cutting edge must be sharp; The cutting tool golden phase structure cannot because rub truncates the heat but to destroy. Thus when sharpens the hard alloy hob should use one kind of oil base refrigerant, it does not get up to the chlorine and the sulfur the response. Regarding scrapes the hob, sharpens after the coating not likely to use in hob such which the entity semifinished materials hardly rolls being important again. After the hard alloy hob sharpens in front of the coating, suggested carries on the pretreatment to its cutting edge.The hob rewill sharpen can except the cutting surface original coating, this will be able to reduce the cutting tool life. The cutting tool is may again spread. Usually regarding the TiN coating, may spread 3 ~ 4; Says regarding TiCN and the TiALN coating, because coating itself has the very big internal stress, therefore on cutting edge with difficulty again again coating. After several spreading TiN coating, can have the height non-uniformity condition, and influentials the tendency which the level falls off, therefore the original coating must remove.At present has two methods to be possible to remove the cutting tool coating: Chemistry draws back spreads draws back with physics spreads. Draws back with chemistry spreads removes on the hard alloy tools the coating is one kind of fine craft, requests the operator to have the suitable level of expertise. The excessively chemistry draws back spreads not only removes the coating, moreover also will dissolve washes the cobalt cement, the damage hard alloy material microscopic structure. The cutting edge microscopic damage will produce the zigzag surface. In addition, when draws back spreads must to the hob pillow block, in the hole and the sign carries on the protection, in order to avoid damages. But physics spreads, then must carry on by the original cutting tool factory, it involves to puts in order rerubs the hob tooth profile truncates. Although draws back chemistry spreads must be much more expensive than, but obtains is a new hob, the quality and the life all can obtain the guarantee.To gear-hobbing machine requestIn order to fully displays the hard alloy and the coating craft merit, the gear-hobbing machine should do correspondingly improves. At present all advanced gear-hobbing machines all press high speed roll the tooth to carry on the design, its gear-hobbing machine hob rotational speed surpasses 3000r/Min, usually is5000r/Min, the work piece main axle rotational speed and the hob rotational speed match. In addition, the engine bed has very high moves the rigidity and the hot rigidity. The advanced gear-hobbing machine some main design characteristics are: Uses the compound epoxy resin lathe bed, by improves the engine bed the tendency and the static characteristic; Has the constant temperature installment the high speed hob headstock; High speed work piece main axle; May use does, the wet two kinds rolls truncates the craft; Belt electro-optical sensor digital actuation system; The straight line rolls the guide rail system; High speed automatic high-quality goods (2 ~ 3 seconds); The occupying a land area of is compact; According to man-machine engineering design; Services conveniently.Uses scrapes the craftRegardless of is the mechanical type the CNC gear-hobbing machine all can carry on scrapes, but the condition is the engine bed must equip has the work piece to the cutting tool selsyn train system. This may cause to scrape the craft economically, to has on the automatic yummy treats system the engine bed very to be also important. The electronic non- contact system depends on a simulation quantity sensor to send out the pulse to survey the cutting tool main axle, the work piece main axle and the gear position. The engine bed CNC controller carries on processing to these pulses, then is opposite to the work piece main axle in the cutting tool position carries on the adjustment, causes a work piece turn of tooth and the hob knife tooth relative position relations is correct.In scrapes in the craft to have very many merits with the refrigerant: In scrapes in the process, the refrigerant has provided the lubricating ability; Because scrapes produces is not the normal scrap, the temperature control is extremely important. Blows the scrap small is thin, does not look like normal knife filings such to be possible to carry off many quantity of heats, therefore scrapes time uses the refrigerant to be possible to control the cutting tool, the work piece and the engine bed system temperature; The refrigerant may washes away the scrap from the cutting tool and the work piece; Improved the work piece surface fine roughness; Enhanced the cutting tool life."Rolls in the green truncates" in the craft, correctly chooses the tooth thick remainder is very important. The recommendation choice down milling rolls the tooth, because it may obtain the thickest scrap, this is helpful to the control cutting process dynamic condition, enhances the cutting tool life. The experience proved that, the cutting speed may surpass 200m/Min, enters for the quantity choice is decided by the superficially attractive fineness which must achieve. The model enters for the scope is 0.5 ~ 1.25mm/R. The cutting tool shifts (flees knife) the method very to be also important, because scrapes time only then the rough machining section partial cutting edges only then undergo the attrition. On the contrary, in "the green cutting" in the process, the cutting tool precision work has partially undertaken the main process load. This meant when scraping flees the knife quantity to be supposed to be bigger, when like the gear is 12 ~ 48DP, each time flees the knife quantity is 0.3 ~ 0.4mm.Scrapes the hob the selectionScrapes the hard alloy hob to divide into two big kinds: Uses in 10DP or the bigger modulus hob, usually all designs has a negative rake front the cutting, when the cutting edge contacts to the hard tooth face, reduced to the hard alloy material impact; Regarding the small modulus gear, does not need to have the negative rake. The negative rake hob shortcoming is sharpens the difficulty. After the hob sharpens the outer diameter to reduce, in order to obtain the correct negative rake to be supposed to change the grinding wheel the bias quantity.When scrapes, the big modulus gear, its addendum, the outer annulus diameter and the tooth root spot all are usually not rolled truncates, and has a smooth transition a request turn of tooth to the tooth root. In order to obtain sinks cuts with the integrity transition circular arc radius, enhances the tooth root the anti- curved intensity, uses in the big modulus gear ideal scraping the hob to be supposed to have the flange. Regarding the small modulus gear processing, should use the standard hob. Uses the standard in front of the radial direction the angle hard alloy hob processing to be called "the hard alloy hob to roll again cuts", but is not "scrapes", latter referred has used a negative rake hob.Hardly rolls the specification which truncates and hardly scrapes the specification which, or the hard alloy hob rolls again truncates nearly same, similarity is uses the strategy which flees the knife to shift to be different. When hardly rolls, the scrap excision must spend the massive energies. This energy finally becomes the quantity of heat. Tries to carry off very important these thermal sending out. After the suggestion processes a work piece every time, the hob flees a position entire tooth pitch. When the hob will flee from beginning to end the position from now on, will be supposed to transfer to the hob to the initial position has a bias quantity the spot. This bias quantity is decided by the hob design and the application, its goal is for be helpful to the hob uniform wear. Another one similarity is the attire which uses clamps the system. As a result of the enormous cutting force, the jig must safely clamp the work piece. The processing result indicated that, the identical helical gear when hardly rolls again with the hard alloy hob, its gear quality is very high, the tooth profile approaches the AGMA10 level, the tooth to surpasses the AGMA12 level with the tooth pitch; The entire hard semifinished materials hardly roll cut the processing the helical gear, its gear precision extremely is also high, the tooth profile precision may reach the AGMA10 level, the tooth to may achieve the AGMA12 level with the tooth pitch. ConclusionAt present has explored many economies the method to process the hard gear, including the material choice, the soft processing method, the heat treatment craft and the hard precision work, enable the hard gear to obtain the popularization, has satisfied the high grade transmission device to the hard gear request.Carries on from entity entire hard work piece semifinished materials hardly rolls cuts the processing is one kind of new processing craft. Because has a rigid better engine bed and the high quality hard alloy tools material and performs coating processing, causes hardly to roll slivers is one effective processing method. Indicatedfrom the factory practical application result that, the hard gear rolls cuts (hardly rolls) the craft to have the broad application prospect.译文：淬硬齿轮的加工【摘要】用于动力传动的齿轮和齿轮箱，其尺寸要求更小，齿轮传动的噪音更低，从而导致对淬硬齿轮的需求，也给齿轮制造厂家提出了探索齿轮加工新方法的要求.概述用于动力传动的齿轮和齿轮箱，其尺寸要求更小，齿轮传动的噪音更低，从而导致对淬硬齿轮的需求，也给齿轮制造厂家提出了探索齿轮加工新方法的要求。

齿轮及其加工中英文翻译对照表A.1. abrasive tooth wear 齿面研磨磨损2. absolute tangential velocity 绝对切向速度3. accelerometer 加速表4. addendum 齿顶高5. addendum angle 齿顶角6. addendum circle 齿顶圆7. addendum surface 上齿面8. adhesive wear 粘着磨损9. adjustability 可调性10. adjustability coefficients 可调系数11. adjusting wedge 圆盘端铣刀的可调型楔块12. allowable stress 允许应力13. alternate blade cutter 双面刀盘14. angular backlash 角侧隙15. angular bevel gears 斜交锥齿轮16. angular displacement 角移位17. angular pitch 齿端距18. angular testing machine 可调角度试验机19. approach action 啮入20. arbor 心轴21. arbor distance 心轴距22. arc of approach 啮入弧23. arc of recess 啮出弧24. attraction 收紧25. average cutter diameter 平均刀尖直径26. axial displacement 轴向位移27. axial factor 轴向系数28. axial locating surface 轴向定位面29. axial pitch 轴向齿距30. axial plane 轴向平面31. axial rakeangle 轴向前角32. axial thrust 轴向推力33. axle testing machine 传动桥试验机B.1． back angle 背锥角2． Back angle distance 背角距（在背锥母线方向）3． Back cone 背锥4． Back cone distance 背锥距5． Back cone element 背锥母线6． Backlash 侧隙7． Backlash tolerance 侧隙公差8． Backlash variation 侧隙变量9． Backlash variation tolerance 侧隙变量公差10． Bandwidth 频带宽11． Base circle 基圆12． Base diameter 基圆直径13． Base pitch 基节14． Base radius 基圆半径15． Base spiral angle 基圆螺旋角16． Basic rack 基本齿条17． Bearing 轴承18． Bearing preload 轴承预负荷19． Bearing spacing／spread 轴承间距20． Bending fatigue 弯曲疲劳21． Bending stress 弯曲应力22． Bevel gears 锥齿轮23． Bias 对角接触24． Bias in 内对角接触25． Bias out 外对角接触26． Blade angle 刀齿齿廓角27． Blade edge radius 刀尖圆角半径28． Blade letter 刀尖凸角代号29． Blade life 刀尖寿命30． Blade point width 刀顶宽31． Blank offset 毛坯偏置距32． Bland position 毛坯位置33． Bottom land 齿槽底面34． Boundary lubrication 界面润滑35． Breakage 破裂36． Bridged contact pattern 桥型接触斑点37． Broach 拉刀38． Burnishing 挤齿C．1. Case crushing 齿面塌陷2. CBN 立方氮化硼3. chamfer 倒角4. chordal addendum 弦齿高5. chordal thickness 弦齿厚6. chuck 卡盘7. circular broach 圆拉刀8. circular face-mill 圆盘端面铣刀9. circular peripheral-mill 圆盘铣刀10. circular pitch 周节11. circular thickness 弧齿厚12. circular thickness factor 弧齿厚系数13. clearance 顶隙14. clearance angle 后角15. coarse pitch 大节距16. coast side 不工作齿侧17. combination 组合18. combined preload 综合预负荷19. complementary crown gears 互补冠状齿轮20. completing cycle 全工序循环21. composite action 双面啮合综合检验误差22. compressive stress 压应力23. concave side 凹面24. concentricity 同心度25. concentricity tester 同心度检查仪26. cone distance 锥距27. cone element 锥面母线28. conformal surfaces 共型表面29. coniskoid 斜锥齿轮30. conjugate gears 共轭齿轮31. conjugate racks 共轭齿条32. contact fatigue 接触疲劳33. contact norma 接触点法线34. contact pattern (tooth contactpattern) 轮齿接触斑点35. contact ratio 重合度36. contact stress 接触应力37. continuous index 连续分度38. control gear 标准齿轮，检验用齿轮39. convex side 凸面40. coolant 冷却液41. corrosive wear 腐蚀性磨损42. corrugated tool 阶梯刨刀43. counter forma surfaces 反法向表面44. cradle 摇台45. cradle test roll 摇台角46. cross 大小端接触47. crossing point 交错点48. crown 齿冠49. crown circle 锥齿轮冠圆50. crowned teeth 鼓形齿51. crown gear 冠轮52. crown to back （轮冠距）轮冠至安装定位面距离53. crown to crossing point 轮冠至相错点距离54. cutter 刀盘55. cutter axial 刀盘的轴向位置56. cutter axial plane 刀盘轴向平面57. cutter axis 刀盘轴线58. cutter diameter 刀盘直径59. cutter edge radius 刀刃圆角半径60. cutter head 刀盘体61. cutter number 刀号62. cutter parallel 刀盘平垫片63. cutter point diameter 刀尖直径64. cutter point radius 刀尖半径65. cutter point width 刀顶距66. cutter spindle 刀盘主轴67. cutter spindle rotation angle 刀盘主轴转角68. cutting distance 切齿安装距69. C.V. testing mashing 常速试验机70. cyclex 格里森粗铣精拉法圆盘端铣刀71. cylindrical gears 圆柱齿轮D.1． Datum tooth 基准齿2． Debur 去毛刺3． Decibel (CB) （噪音）分贝4． Decimal ratio 挂轮比值5． Dedendum 齿根高6． Dendendum angle 齿根角7． Dedendum surface 下齿面8． Deflection 挠曲9． Deflection test 挠曲试验10． Deflection testing machine 挠曲试验机11． Depthwise taper 齿高收缩12． Design data sheet 设计数据表13． Destructive pitting 破坏性点蚀14． Destructive wear 破坏性磨损15． Developed setting 试切调整16． Dial indicator 度盘式指示表17． Diametral pitch 径节18． Diamond 菱形接触19． Dinging ball check 钢球敲击检查20． Disc-mill cuter 盘铣刀21． Dish angle 凹角22． Displacement 位移23． Displacement error 位移误差24． Double index 双分度25． Double roll 双向滚动26． Down roll 向下滚动27． Drive side 工作齿侧28． Duplete 双刃刀29． Duplex 双重双面法30． Duplex helical 双重螺旋法（加工方法之一）31． Duplex spread blade 双重双面刀齿（加工／磨齿方法）32． Duplex taper 双重收缩齿33． Durability factor 耐久系数34． Dynamic factor 动载荷系数E。

齿在轴向的宽度。

齿腹：节圆和齿底之间的表面。

斜齿轮：这些齿轮的齿相对于齿轮轴线由一个角度或螺旋角度，它们比直齿圆柱齿轮的制造更难，造价更昂贵，但是它们传动无噪音并且可靠。

它们可以用来在相同或不同平面中构成一定角度的相两轴之间的力的传递。

人字形齿轮：人字形齿轮是在齿轮两边有相同数量在左旋和右旋形的齿轮。

由于齿轮有角度，齿轮制造时需要考虑轴受到的轴向力，人字形齿轮是用平衡的方法来抵消轴向推力的，固而允许选用轻系列轴承取代重系列轴承，甚至可以完全取消轴承，通常在切削加工中在齿轮的周围有一个中心槽来抵消。

锥齿轮：锥齿轮用作互相不平行的轴之间的连接。

通常轴之间的夹角是90度，但它们比90多或少，相啮合的两齿轮仅改变运动方向，或者为改变速度具有不同的齿数，齿的表面沿着圆锥的表面，圆头齿之间不相互平行，它就使得在机械加工中产生类似的问题及必须要一套夹具。

齿轮的线可能是直的或螺旋的，因此有平直的锥齿和螺旋的锥齿。

蜗杆和蜗轮：蜗杆蜗轮机构主要用作有限空间需较小齿轮的体积的情况。

通常蜗杆为主动件并且不能颠倒，也就是说，蜗轮不能作为主动件。

许多蜗杆能左右移动，转动为顺时针或逆时针。

齿条：齿条是有无穷半径的齿轮或是边缘随着直线扩展的齿轮，它被用来往复运动改变为螺旋运动或反过来，车床齿条和小齿轮是这种机器的最好例子。

各种材料被用于制造齿轮。

通常被选用的材料取决于齿轮的制造与齿轮将来的实现用途，齿轮能被铸，轧或挤压出来。

材料类型包括：铸铁碳素钢，合金钢，铝，青铜，尼龙。

附录：GearsAbstract: Gear is power element in the machine, is used to pass between the shaft and shaft movement and power. They may just was used to relay movement, that is one part to another part of the machine, or be used to change the relative spee d and torque between shaft and shaft, the first to be discovered with gear machine is horological, in fact, the gear of the clock is very small compared with the gear train. As the widely used in the gear in the actual environment, people in the asp ect of the application of the gear for a lot of research and investigation. now, gear drive than ever to have to pass a heavy load, and under the high speed running. The engineers and mechanics are considering the factors that exist in a mechanical.Keywords: Gear，Strength，check.Super Gears：Spur gears will be considered first for several reasons.In the first place ,they are simplest and the least expensive of gears and they may be used to transmit power betw een parallel shafts,also,spur gears definitions are usually applicable to other types .It is imp ortant go understand the following definitions,since they are important factors in the desig n of any equipment utilizing gears. Diametric Pitch The number of teeth per inch of pitch cirle diameter .The diameter pitch is usually an integer .A small number for the pitch imp lies a large tooth size.Meshing spur gears must have the same diameter pitch .The speed rat io is based on the fact that meshing gears may have different-sized pitch circles and henc e different number of teeth.Circular Pitch：The distance from a point on one tooth to the corresponding point on an adjacent tooth ,m easrued along the pitch circle.This is a liner dimension and thus bas liner units.Pitch Circle：The circle on which the ratio of the gear set is based,when two gears are meshing ,the tw o pitch circles must be exactly tangent if the gears are to function properly.The tangency p oint is known as the pitch point.Pressure Angle：The angle between the line of action and a line perpendicular to the centerlines of the tw o gears in mesing .Pressure Angles for spur gears are usually 14.5 or 20 degrees,although o ther values can be used.Meshing gears must have the same pressure angles.In the case of a rack,the teeth have the straight sides inclined at an angle corresponding to the pressure a ngle.Base Circle：A circle tangent to the line of action (or pressure line ) .The base circle is the imaginary cir cle about which an involutes cure is developed .Most spur gears follow an involutes cure fr om the base circle to the top of the tootch,this cure can be visualized by observing a point o n a taut cord an it is unwound from a cylinder .In a gear ,the cylinder is the best circle.Addendum：The radial distance form the pitch circle to the top of the tooth .Dedendum：The radial distance from file pitch circle to the root of the tooth.Clearance：The difference between the addendum and the addendum.Face Width：The width of the tooth measured axially.Face：The surface between the pitch circle and the top of the tooth.Flank：The surface between the pitch circle and the bottom of the tooth.Helical Gears：These gears have their tooth element at an angle or helix to the axis of the gear.The-y are more difficult and expensive to make than spur gears,but are quieter and stronger. They may be used to transmit power between parallel shafts at an angle to each in the same o r different planes.Herringbone Gears：A herringbone gear is equivalent to a right-hand and a left-hand helical gear placed side b y side.Because of the angle of the tooth,helicalgears create considerable side thrust on the shaft. A herringbone gear corrects this thrust b y neutralizing it ,allowing the use of a small thrust bearing instead of a large one and perha ps eliminating one altogether.Often a central groove is made round the gear for ease in mac hining.Bevel Gears：Bevel gears are used to connect shafts, which are not parallel to each ually the sha fts are 90 deg.To each other, but they may be more or less than 90 deg.The two meshing ge ars may have the same number of teeth for the purpose of changing direction of motion onl y,or they may have a different number of teeth for the purpose of changing both speed an d irection .The faces of the teeth lie on the surface of the frustum of a cone,therefore the te eth elements are not parallel to each other it can be seen that this lack of parallelism create s a machining problem so that two passes with a tool must be made.The tooth elements ma y be straight or spiral ,so that we have plain anti spiral evel gears.Worm and Worm Gears：A worm-and-worm-gear combination is used chiefly where it is desired to obtain a high ge ar reduction in a limited space,normally the worm drivers the worm gear and is not reversi ble ,that is to say,the worm gear can not drivethe worm.Most worms can be rotated in either direction,clockwise or counterclockwise. Ra cks A rack is a gear with an infinite radius,or a gear with its perimeter stretched out into a straight line.It is used to change reciprocating motion to rotary motion or vice versa.A l athe rack and pinion is a good example of this mechanism.Various materials are used in manufacturing gears.Usually,the materials selected depends on the method used for making the gear and the ap注：1. 指导教师对译文进行评阅时应注意以下几个方面：①翻译的外文文献与毕业设计（论文）的主题是否高度相关，并作为外文参考文献列入毕业设计（论文）的参考文献；②翻译的外文文献字数是否达到规定数量（3 000字以上）；③译文语言是否准确、通顺、具有参考价值。

英文原文Gear manufacturing methodsThere are two basic methods of manufacturing gear teeth: the generating process and the forming process. when a gear tooth is generated, the workpiece and the cutting or grinding tool are in continuous mesh and the tooth form is generated by the tool. In other words, the work and the tool are conjugated to each other. hobbing :machines, shaper cutters, shaving machines, and grinders use this principle.When a gear tooth is formed, the tool is in the shape of the space that is being machined out. Some grinding machines use this principle with an indexing mechianism which allows the gear teeth to be formed tooth by tooth. Broaches are examples of form tools that machine all the gear teeth simultaneously.shapingShaping is inherently similar to planning but uses a circular cuttrer instead of rack and the resulting reduction in the reciprocating inertia allows much higher stroking speeds: modern shapers cutting car gears can run at 2,000 cutting strokes per minmute. The shape of the cutter is roughly the same as an involute gear but the tips of the teeth are rounded.The generating drive between cutter and workpiece does not involve a rack or leadscrew since only circular motion in involved. The tool and workpiece move tangential typically 0.5 mm for each stroke of the cutter. On the return stroke the cutter must be retracted about 1 mm to give clearance otherwise tool rub occurs on the backstroke and failure is rapid. The speed on this type of machine is limited by the rate at which some 50kg of cutter and bearings can be moved a distance of 1 mm. the accelerations involved tequire forces of the order of 5000N yet high accuracy must be maintained.The advantages of shaping are that production rates are relatively high and that it is possible to cut right up to a shoulder. Unfortunately, for helical gears, a helical guide is required to impose a rotational motion on the stroking motion; such helical guides cannot be produced easily or cheaply so the method is only suitable for long runs with helical gears since special cutters and guides must be manufactured for each different helix angle. A great advantage of shaping is its ability to annular gears such as those required for large epicyclie drives.When very high accuracy is of importance the inaccuracies in the shaping cutter matter since they may transfer to the cut gear. It is obvious that profile errors will transfer but it is less obvious than an eccentrically mounted or ground cutter will give a characteristic “dropped tooth”. There are several causes for “dropped tooth” but it occurs most commonly when the diameter of the workpiece is about half, one and half, two and a half, etc, times the cutter diameter. If the cutter starts on a high point and finishes on a low point during the final finishing revolution of the gear the peak to peak eccentricity errors in the cutter occurs between the last and the first tooth of the final revolution of the cut gear; as the cumulative pitch error of the cutter may well be over 25 microns there is a sudden pitch error of this amount on the cut gear. The next gear cut on the machine may however be very good on adjacent pitch if the final cut happened to start in a favorable position on the cutter.Various attempts have been made to prevent this effect, in particular by continuing rotation without any further cutter infeed but if the shaping machine is not very rigid and the cutter very sharp then no further cutting will occur and the error will not be removed.hobbinghobbing, the most used metal cutting method, uses the rack generating principle but avoids slow reciprocation by mounting many “racks ” on a rotating cutter. The “racks” are displaced axially to form a gashed worm. The “racks” do not generate the correct involute shape for the whole length of the teeth since they are moving on a circular path and so the hob is fed slowly along the teeth either axially in normal or in the direction of the helix in “oblique” hobbing.Metal removal rates are high since no reciprocation of hob or workpiece is required and so cutting speeds of 40 m/min can be used for conventional hobs and up to 150m/min for carbide hobs. Typically with a 100mm diameter hob the rotation speed will be 100rpm and so a twenty tooth workpiece will rotate at 5 rpm. Each revolution of the workpiece will correspond to 0.75mm feed so the hob will advance through the workpiece at about 4mm per minute. For car production roughing multiple start hobs can be used with coarse feeds of 3mm per revolution so that 100 rpm on the cutter, a two-start hob and a 20 tooth gear will give a feed rate of 30mm/minute.The disadvantage of a coarse feed rate is that a clear marking is left on the workpiece, particularly in the root, showing a pattern at a spacing of the feed rate per revolution. This surface undulation is less marked on the flanks than in the root and is not important when there is a subsequent finishing operation such as shaving or grinding. When there are no further operations the feed per revolution must be restricted to keep the undulations below a limit which is usually dictated by lubrication conditions. The height of the undulations in the root of the gear is given by squaring the feed per revolution and dividing by four times the diameter of the hob; 1 mm feed and 100mm diameter gives 2.5 micron high undulations in the root. On the gear flank the undulation is roughly cos70 as large, i.e., about 0.85 micron.Accuracy of hobbing is normally high for pitch and for helix, provided machines are maintained; involute is dependent solely on the accuracy of the hob profile. As the involute form is generated by as many cuts as there are gashes on the hob the involute is not exact, but if there are, say, 14 tangents generating a flank of 20 mm radius curvature about 4 mm high the divergence from a true involute is only about half a micron; hob manufacturing and mounting errors can be above 10 microns. Use of twostart hobs or oblique hobbing gives increased error levels since hob errors of pitching transfer to the cut gear.broachingBroaching is not used for helical gears but is useful for internal spur gears; the principal use of broaching in this context is for internal splines which cannot easily be made by any other method. As with all broaching the method is only economic for large quantities since setup costs are high.The major application of broaching techniques to helical external gears is that used by Gleasons in their G-TRAC machine .this machine operates by increasing the effective radius of a hobbing cutter to infinity so that each tooth of the cutter is travelingin a straight line instead of on a radius. This allows the cutting action to extend over the whole facewidth of a gear instead of the typical 0.75 mm feed per revolution of hobbing. The resulting process gives a very high production rate , more suitable for U.S.A. production volumes than for the relatively low European volumes and so, despite a high initial cost ,is very competitive.Broaching give high accuracy and good surface finish but like all cutting processes is limited to “soft” materials which must be subsequently casehardened or heat treated, giving distortion.ShavingA shaving cutting cutter looks like a gear which has extra clearance at the root and whose tooth flanks have been grooved to give cutting edges. It is run in mesh with the rough gear with crossed axes so that there is in theory point contact with a relative velocity along the teeth giving scraping action. The shaving cutter teeth are relatively flexible in bending and so will only operate effectively when they are in double contact between two gear teeth. The gear and cutter operate at high rotational speeds with traversing of the workface and about 100 mm micron of material is removed. Cycle times can be less than half a minute and the machines are not expensive but cutters are delicate and difficult to manufacture. It is easy to make adjustments of profile at the shaving stage and crowning can be applied. Shaving can be carried out near a shoulder by using a cutter which is plunged in to depth without axial movement; this method is fast but requires more complex cutter design.grindingGrinding is extremely important because it is the main way hardened gear are machined. When high accuracy is required it is not sufficient to pre-correct for heat treatment distortion and grinding is then necessary.The simplest approach to grinding, often termed the Orcutt method. The wheel profile is dressed accurately to shape using single point diamonds which are controlled by templates cut to the exact shape required; 6:1 scaling with a pantograph is often used. The profile wheel is then reciprocated axially along the gear which rotates to allow for helix angle effects; when one tooth shape has been finished, involving typically 100 micron metal removal the gear is indexed to the next tooth space. This method is fairly show but gives high accuracy consistently. Setting up is lengthy because different dressing templates are needed if module, number of teeth, helix angle, or profile correction are changed.The fastest grinding method uses the same principle as hobbing but replaces a gashed and relieved worm by a grinding wheel which is a rack in section. Since high surface speeds are needed the wheel diameter is increased so that wheels of 0.5 m diameter can run at over 2000 rpm to give the necessary 1000 m/min. only single start worms are cut on the wheel but gear rotation speeds are high,100 rpm typically, so it is difficult to design the drive system to give accuracy and rigidity. Accuracy of the process is reasonably high although there is a tendency for wheel and workpiece to deflect variably during grinding so the wheel form may require compensation for machine deflection effects. Generation of a worm shape on the grinding wheel is a slow process since a dressing diamond or roller must not only form the rack profile but has to move axially as the wheel rotates. Once the wheel has been trued, gears can be groundrapidly until redressing is required. This is the most popular method for high production rates with small gear and is usually called the Reishauer method.Large gears are usually generated by the Maag method which is similar to planning in its approach but uses cup grinding wheels of large diameter to form the flanks of the theoretical mating rack. Gears of very large diameter cannot easily be moved so the gear is essentially stationary while the grinding wheel carriage reciprocates in the direction of the helix. The wheel is only in contact over a small part of the facewidth in helical gears so this is not important when only a few gears of this size are made in a year. As with form grinding, after grinding a pair of flanks the gear is indexed to the next pair.A similar method used for medium size gears has stationary wheels, while the rough gear is traversed under the wheels. Corresponding rotational movement of the gear is controlled by steel bands unwrapping from a cylinder of pitch circle diameter so that the motion of gear relative to “rack” is correct.Another method, the Nile approach, uses a wheel which is formed to give the “theoretical mating rack” instead of using two cup wheels as in the Maag method. This approach is best suited to medium precision work on smaller gears and is intermediate in speed between the Reishauer and Maag methods.All grinding processes are slow and costly compared with cutting processed and so are only used when accuracy is essential. A rough rule of thumb is that grinding will increase gear cutting costs by a factor of 10 but the cost of the teeth is often only a small part of the total cost of a gearbox. The accuracies attainable are surprisingly not very dependent on size of gear ; whether a gear is 5 m or 50 m diameter the pitch involute and helix accuracies attainable are of the order of 5 microns or better and more dependent on the skill and patience of the operator and inspectors than on any other factors.It is often assumed that grinding will remove all error generated at the roughing stage. Unfortunately, grinding machines are relatively flexible and so the grinding wheel has a tendency to follow previous errors. The errors will thus be reduced but not completely eliminated unless very many cuts are used; whenever a grinding process is giving in consistent results it is advisable to check the accuracies at the rough-cut stage. The only exception is the form grinding process which will not follow involute errors though it will still allow helix and pitch errors.中文译文齿轮的加工方法加工齿轮轮齿有两种基本的方法：产生过程和形成过程。

毕业设计(论文)外文资料翻译学院：专业：机械设计制造及其自动化姓名：学号：外文出处： Mechanism and Machine Theory34 (1999) 857-876(用外文写)附件： 1.外文资料翻译译文；2.外文原文。

附件1：外文资料翻译译文动力传动圆锥渐开线齿轮的设计、制造和应用Dr. J. Börner,K. Humm,Dr. F. Joachim,Dr. H. akaria,ZF Friedrichshafen AG , 88038Friedrichshafen, Germany；[摘要]圆锥渐开线齿轮(斜面体齿轮)被用于交叉或倾斜轴变速器和平行轴自由侧隙变速器中。

圆锥齿轮是在齿宽横断面上具有不同齿顶高修正(齿厚)的直齿或斜齿圆柱齿轮。

这类齿轮的几何形状是已知的，但应用在动力传动上则多少是个例外。

ZF公司已将该斜面体齿轮装置应用于各种场合:4W D轿车传动装置、船用变速器(主要用于快艇)机器人齿轮箱和工业传动等领域。

斜面体齿轮的模数在0. 7 mm-8 mm之间，交叉传动角在0°- 25°。

之间。

这些边界条件需要对斜面体齿轮的设计、制造和质量有一个深入的理解。

在锥齿轮传动中为获得高承载能力和低噪声所必须进行的齿侧修形可采用范成法磨削工艺制造。

为降低制造成本，机床设定和由于磨削加工造成的齿侧偏差可在设计阶段利用仿真制造进行计算。

本文从总体上介绍了动力传动变速器斜面体齿轮的研发，包括:基本几何形状、宏观及微观几何形状的设计、仿真、制造、齿轮测量和试验。

1前言在变速器中如果各轴轴线不平行的话，转矩传递可采用多种设计，例如:伞齿轮或冠齿轮、万向节轴或圆锥渐开线齿轮(斜面体齿轮)。

圆锥渐开线齿轮特别适用于小轴线角度(小于15°)，该齿轮的优点是在制造、结构特点和输入多样性等方而的简易。

圆锥渐开线齿轮被用于直角或交叉轴传动的变速器或被用于平行轴自由侧隙工况的变速器。

毕 业 设 计（论文）（说 明 书）题 目： 齿轮的加工工艺 姓 名： 编 号：年 月 日摘要本论文系统的讲述了齿轮加工工艺的的过程及圆柱齿轮的加工工艺。

讨论了几种常见齿轮齿形加工的方法和根切现象并给出计算公式。

并且讲述了齿轮加工中常见的的加工误差；以保证齿轮加工的准确性。

本论文是关于齿轮的加工工艺，以介绍方法为宗旨，着重实力，力图做到内容完整、详实。

主要介绍机械制造工艺规程设计的基本要求、内容、方法和步骤。

通过对齿轮的齿型加工分析及齿轮加工误差的分析可以更准确的把握住齿轮的加工工艺过程；进而加工出精度更高的齿轮.关键词：加工工艺齿型的加工加工误差AbstractThis paper describes the system processing of the process of gear and gear processing technology. Discussed several common processing methods and gear tooth root cutting in and give the formula.And describes the common gear machining processing error; to ensure the accuracy of gear.This paper is about the gear processing technology, to introduce methods for the purpose, focus on strength, trying to make the content complete and informative.Machinery manufacturing process specification introduces the basic requirements for the design, content, methods and steps.Through analysis of gear-type processing and manufacturing error of analysis can more accurately grasp the gear machining process; further be processed more precise gear.Key words: tooth processing processing processing errors目录摘要 (2)第1章前言 (1)第2章齿轮加工概述 (2)2.1圆柱齿轮的结构特点 (2)2.2圆柱齿轮的传动精度要求 (2)2.3齿轮的材料、热处理及毛坯 (3)2.4齿轮齿形加工方法及选择 (6)第3章圆柱齿轮的加工工艺过程 (12)3.1工艺过程分析 (12)3.2齿端加工 (15)3.3精基准修正 (16)第4章齿轮加工误差工艺分析 (17)4.1影响传动精度的加工误差分析 (17)4.2影响齿轮工作平稳性的加工误差分析 (21)4.3影响齿轮接触精度的加工误差分析 (22)第5章结论 (24)参考文献 (25)致谢 (26)第1章前言齿轮是机器中广泛采用的传动零件之一。

机械制造毕业设计外文英文文献翻译齿轮和齿轮传动Gears and gear driveGears are the most durable and rugged of all mechanical drives. They can transmit high power at efficiencies up to 98% and with long service lives. For this reason, gears rather than belts or chains are found in automotive transmissions and most heavy-duty machine drives. On the other hand, gears are more expensive than other drives, especially if they are machined and not made from power metal or plastic.Gear cost increases sharply with demands for high precision and accuracy. So it is important to establish tolerance requirements appropriate for the application. Gears that transmit heavy loads or than operate at high speeds are not particularly expensive, but gears that must do both are costly.Silent gears also are expensive. Instrument and computer gears tend to be costly because speed or displacement ratios must be exact. At the other extreme, gears operating at low speed in exposed locations are normally termed no critical and are made to minimum quality standards.For tooth forms, size, and quality, industrial practice is to follow standards set up by the American Gear Manufactures AssociationAGMA.Tooth formStandards published by AGMA establish gear proportions and tooth profiles. Tooth geometry is determined primarily by pitch, depth, and pressure angle.Pitch：Standards pitches are usually whole numbers when measured as diametral pitch P. Coarse-pitch gearing has teeth larger than 20 diametral pitch ?usually 0.5 to 19.99. Fine-pitch gearing usually has teeth of diametral pitch 20 to 200.Depth: Standardized in terms of pitch. Standard full-depth have working depth of 2/p. If the teeth have equal addendaas in standard interchangeable gears the addendum is 1/p. Stub teeth have a working depth usually 20% less than full-depth teeth. Full-depth teeth have a larger contract ratio than stub teeth. Gears with small numbers of teeth may have undercut so than they do not interfere with one another during engagement. Undercutting reduce active profile and weakens the tooth.Mating gears with long and short addendum have larger load-carrying capacity than standard gears. The addendum of the smaller gear pinion is increased while that of larger gear is decreased, leaving the whole depth the same. This form is know as recess-action gearing.Pressure Angle: Standard angles are and . Earlier standards include a 14-pressure angle that is still used. Pressure angle affectsthe force that tends to separate mating gears. High pressure angle decreases the contact ratio ratio of the number of teeth in contact but provides a tooth of higher capacity and allows gears to have fewer teeth without undercutting.Backlash: Shortest distances between the non-contacting surfaces of adjacent teeth .Gears are commonly specified according to AGMA Class Number, which is a code denoting important quality characteristics. Quality number denote tooth-element tolerances. The higher the number, the closer the tolerance. Number 8 to 16 apply to fine-pitch gearing.Gears are heat-treated by case-hardening, through-hardening, nitriding, or precipitation hardening. In general, harder gears are stronger and last longer than soft ones. Thus, hardening is a device that cuts the weight and size of gears. Some processes, such as flame-hardening, improve service life but do not necessarily improve strength.Design checklistThe larger in a pair is called the gear, the smaller is called the pinion.Gear Ratio: The number of teeth in the gear divide by the number of teeth in the pinion. Also, ratio of the speed of the pinion to the speed of the gear. In reduction gears, the ratio of input to output speeds.Gear Efficiency: Ratio of output power to input power. includesconsideration of power losses in the gears, in bearings, and from windage and churning of lubricant.Speed: In a given gear normally limited to some specific pitchline velocity. Speed capabilities can be increased by improving accuracy of the gear teeth and by improving balance of the rotating parts.Power: Load and speed capacity is determined by gear dimensions and by type of gear. Helical and helical-type gears have the greatest capacity to approximately 30,000 hp. Spiral bevel gear are normally limited to 5,000 hp, and worm gears are usually limited to about 750 hp.Special requirementsMatched-Set Gearing: In applications requiring extremely high accuracy, it may be necessary to match pinion and gear profiles and leads so that mismatch does not exceed the tolerance on profile or lead for the intended application.Tooth Spacing: Some gears require high accuracy in the circular of teeth. Thus, specification of pitch may be required in addition to an accuracy class specification.Backlash: The AMGA standards recommend backlash ranges to provide proper running clearances for mating gears. An overly tight mesh may produce overload. However, zero backlash is required in some applications.Quiet Gears: To make gears as quit as possible, specify thefinest pitch allowable for load conditions. In some instances, however, pitch is coarsened to change mesh frequency to produce a more pleasant, lower-pitch sound. Use a low pressure angle. Use a modified profile to include root and tip relief. Allow enough backlash. Use high quality numbers. Specify a surface finish of 20 in. or better. Balance the gear set. Use a nonintegral ratio so that the same teeth do not repeatedly engage if both gear and pinion are hardened steel. If the gear is made of a soft material, an integral ratio allows the gear to cold-work and conform to the pinion, thereby promoting quiet operation. Make sure critical are at least 20% apart from operating speeding or speed multiples and from frequency of tooth mesh.Multiple mesh gearMultiple mesh refers to move than one pair of gear operating in a train. Can be on parallel or nonparallel axes and on intersection or nonintersecting shafts. They permit higer speed ratios than are feasible with a single pair of gears .Series trains:Overall ratio is input shaft speed divided by output speed ,also the product of individual ratios at each mesh ,except in planetary gears .Ratio is most easily found by dividing the product of numbers of teeth of driven gears by the product of numbers of teeth of driving gears.Speed increasers with step-up rather than step-down ratios mayrequire special care in manufacturing and design. They often involve high speeds and may creste problems in gear dynamics. Also, frictional and drag forces are magnified which, in extreme cases , may lead to operational problems.Epicyclic Gearing:Normally, a gear axis remains fixed and only the gears rotates. But in an epicyclic gear train, various gears axes rotate about one anther to provide specialized output motions. With suitable clutchse and brakes, an epicyclic train serves as the planetary gear commonly found in automatic transmissions.Epicyclic trains may use spur or helical gears, external or internal, or bevel gears. In transmissions, the epicyclic or planetary gears usually have multiple planets to increase load capacity.In most cases, improved kinematic accuracy in a gearset decreases gear mesh excitation and results in lower drive noise. Gearset accuracy can be increased by modifying the tooth involute profile, by substituting higher quality gearing with tighter manufacturing tolerances, and by improving tooth surface finish. However, if gear mesh excitation generaters resonance somewhere in the drive system, nothing short of a “perfect” gearset will substantially reduce vibration and noise.Tooth profiles are modified to avoid interferences which can result from deflections in the gears, shafts, and housing as teeth engageand disendgage. If these tooth interferences are not compensated for by profile modifications, gears load capacity can be seriously reduced. In addition, the drive will be noisier because tooth interferences generate high dynamic loads. Interferences typically are eliminated by reliving the tooth tip, the tooth flank, or both. Such profile modifications are especially important for high-load , high-speed drives. The graph of sound pressure levelvs tip relief illustrates how tooth profile modifications can affect overall drive noise. If the tip relief is less than this optimum value, drive noise increases because of greater tooth interference; a greater amount of tip relief also increase noise because the contact ratio is decreased.Tighter manufacturing tolerances also produce quietier gears. Tolerances for such parameters as profile error, pitch AGMA quality level. For instance, the graph depicting SPL vs both speed and gear quality shows how noise decreases example, noise is reduced significantly by an increase in accuracy from an AGMA Qn 11 quality to an AGNA Qn 15 quality. However, for most commercial drive applications, it is doubtful that the resulting substantial cost increase for such an accuracy improvement can be justified simply on the basis of reduced drive noise.Previously, it was mentioned that gears must have adequate clearance when loaded to prevent tooth interference during the course of meshing. Tip and flank relief are common profile modifications thatcontrol such interference. Gears also require adequate backlash and root clearance. Noise considerations make backlash an important parameter to evaluate during drive design. Sufficient backlash must be provided under all load and temperature conditions to avoid a tight mesh, which creates excessively high noise level. A tight mesh due to insufficient backlash occurs when the drive and coast side of a tooth are in contact simultaneously. On the other hand, gears with excessive backlash also are noisy because of impacting teeth during periods of no load or reversing load. Adequate backlash should be provided by tooth thinning rather than by increase in center distance. Tooth thinning dose not decrease the contact ratio, whereas an increase in center distance does. However, tooth thinning does reduce the bending fatigue, a reduction which is small for most gearing systems.齿轮和齿轮传动在所有的机械传动形式中，齿轮传动是一种最结实耐用的传动方式。

外文原文：In the gear hobbing machine processing , gear requirements , However, the calculation of the differential gear selection especially cumbersome in gear, the helical gear (helical gear) movement and the driving force is to rely on the transmission of axial movement along the access track to achieve the, Helical gear is therefore a direct impact on the machining accuracy of the work of the helical gear stability. And helical gear of all kinds of mechanical processing methods, the first step is the calculation of the differential gear selection.However, due to traditional manual calculation of matching gear is not fast. Precise requirements of the above reasons, we studied differential gear selection algorithm based on the use of computer technology has developed a machine differential gear Select Software, The purpose of choosing this subject is to change the traditional differential gear hobbing machine of choice to find a simple and quick method of high accuracy, to replace the traditional time-consuming and error-prone that the look-up table method, the accuracy of this method is very low, sometimes even adjust the gear machine tools and installation conditions can not be equipped with gear to meet the requirements of the distribution of computing.The use of computer-assisted support options to meet on the set of gear with the requirements. In this paper, the use of computer technology to solve differential gear selection tools that exist in the database form, gear and traditional methods to find the problem of low accuracy, increased machine differential Calculation of gear to find accuracy and speed, the actual production to meet the needs of. Understanding of learning through textbooks differential gear hobbing of computer-assisted selection based on the principles and knowledge, more traditional hanging round the drawbacks of lack of choice. Aware that the choice of a new way the importance of the development.In the early stage of c With a deep understanding of language, according to the actual needs of the work to prepare the diagram c language program, to prepare a set of procedures used to select the right differential gear hobbing machine, debugger interface. Calculation of the transmission ratio and the transmission ratio must meet the conditions of assembly by applying the computer technology has developed a tool to choose software differential gear.Meet the user according to their actual gear machine tool settings with the needs of the situation. Select to differential gear, the gear can detect the correct installationand mating.Understanding of learning through textbooks differential gear hobbing of computer-assisted selection based on the principles and knowledge, more traditional hanging round the drawbacks of lack of choice. Aware of the choice of a new way the importance of the development. In the early stage of c has a profound understanding of the language, according to the actual needs of the work to prepare the diagram c language program, to prepare a set of procedures used to select the right differential gear hobbing machine, debugger interface. Calculation of transmission and the transmission ratio than the assembly must meet the conditions, use of computer technology has developed a tool to choose software differential gear.Meet the user according to their actual gear machine tool settings with the needs of the situation. Options for calculating the differential gear, gear testing whether the correct installation and mating.GOETSGH，D L.Advanced Manufacturing Technology[M].Albany，NY：Delmar Publihers Inc.1990.中文译文：滚齿机加工滚齿机加工齿轮时需要计算挂轮，特别是加工斜齿圆柱齿轮，大质数圆齿轮和用切向走刀加工蜗轮时还需要计算差动挂轮。

齿轮齿轮(Gear) 是依靠齿的啮合传递扭矩的轮状机械零件。

齿轮通过与其它齿状机械零件（如另一齿轮、齿条、蜗杆）传动，可实现改变转速与扭矩、改变运动方向和改变运动形式等功能。

由于传动效率高、传动比准确、功率范围大等优点，齿轮机构在工业产品中广泛应用，其设计与制造水平直接影响到工业产品的质量。

齿轮轮齿相互扣住齿轮会带动另一个齿轮转动来传送动力。

将两个齿轮分开，也可以应用链条、履带、皮带来带动两边的齿轮而传送动力。

基本介绍.齿轮在传动中的应用很早就出现了。

公元前三百多年，古希腊哲学家亚里士多德在《机械问题》中，就阐述了用青铜或铸铁齿轮传递旋转运动的问题。

中国古代发明的指南车中已应用了整套的轮系。

不过，古代的齿轮是用木料制造或用金属铸成的，只能传递轴间的回转运动，不能保证传动的平稳性，齿轮的承载能力也很小。

据史料记载，远在公元前400~200年的中国古代就巳开始使用齿轮，在我国山西出土的青铜齿轮是迄今已发现的最古老齿轮，作为反映古代科学技术成就的指南车就是以齿轮机构为核心的机械装置。

17世纪末，人们才开始研究，能正确传递运动的轮齿形状。

18世纪，欧洲工业革命以后，齿轮传动的应用日益广泛；先是发展摆线齿轮，而后是渐开线齿轮，一直到20世纪初，渐开线齿轮已在应用中占了优势。

早在1694年，法国学者Philippe De La Hire首先提出渐开线可作为齿形曲线。

1733年，法国人M.Camus提出轮齿接触点的公法线必须通过中心连线上的节点。

一条辅助瞬心线分别沿大轮和小轮的瞬心线(节圆)纯滚动时，与辅助瞬心线固联的辅助齿形在大轮和小轮上所包络形成的两齿廓曲线是彼此共轭的，这就是Camus定理。

它考虑了两齿面的啮合状态；明确建立了现代关于接触点轨迹的概念。

1765年，瑞士的L．Euler提出渐开线齿形解析研究的数学基础，阐明了相啮合的一对齿轮，其齿形曲线的曲率半径和曲率中心位置的关系。

后来，Savary进一步完成这一方法，成为现在的Eu-let-Savary方程。

(文档含英文原文和中文翻译)中英文资料对照外文翻译Machine Parts (I)GearsGears are direct contact bodies, operating in pairs, that transmit motion and force from one rotating shaft to another or from a shaft to a slide (rack), by means of successively engaging projections called teeth.Tooth profiles. The contacting surfaces of gear teeth must be aligned in such a way that the drive is positive; i.e., the load transmitted must not depend on frictional contact. As shown in the treatment of direct contact bodies, this requires that thecommon normal to the surfaces not to pass through the pivotal axis of either the driver or the follower.As it is known as direct contact bodies, cycloidal and involute profiles profiles provide both a positive drive and a uniform velocity ratio;i.e., conjugate action.Basic relations. The smaller of a gear pair is called the pinion and the larger is the gear. When the pinion is on the driving shaft the pair is called the pinion and the larger is the gear. When the pinion is on the driving shaft the pair acts as a speed reducer; When the gear drives, the pair is a speed incrreaser. Gears are more frequently used to reduce speed than to increase it.If a gear having N teeth rotates at n revolutions per minute, the product N*n has the dimension “teeth per minute”. This product must be the same for both members of a mating pair if each tooth acquires a partner from the mating gear as it passes through the region of tooth engagement.For conjugate gears of all types, the gear ratio and the speed ratio are both given by the ratio of the number of teeth on the gear to the number of teeth on the pinion. If a gear has 100 teeth and a mating pinion has 20, the ratio is 100/20=5. Thus the pinion rotates five times as fast as the gear, regardless of the gear. Their point of tangency is called the pitch point, and since it lies on the line of centers, it is the only point at which the profiles have pure roling contact. Gears on nonparallel, non-intersecting shafts also have pitch circles, but the rolling-pitch –circle concept is not valid.Gear types are determined largely by the disposition of the shafts; in addition, certain types are better suited than others for large speed changes. This means that if a specific disposition of the shafts is required, the type of gear will more or less be fixed. On the other hand, if a required speed change demands a certain type, the shaft positions will also be fixed.Spur gears and helical gears. A gear having tooth elements that are straight and parallel to its axis is known as a spur gear. A spur pair can be used to connect parallel shafts only.If an involute spur pinion were made of rubber and twisted uniformly so that the ends rotated about the axis relative to one another, the elements of the teeth, initially straight and parallel to the axis, would become helices. The pinion then in effect would become a helical gear.Worm and bevel gears. In order to achieve line contact and improve the load carrying capacity of the crossed axis helical gears, the gear can be made to curvepartially around the pinion, in somewhat the same way that a nut envelops a screw. The result would be a cylindrical worm and gear. Worms are also made in the shape of an hourglass, instead of cylindrical, so that they partially envelop the gear. This results in a further increase in load-carrying capacity.Worm gears provide the simplest means of obtaining large ratios in a single pair. They are usually less efficient than parallel-shaft gears, however, because of an additional sliding movement along the teeth.V-beltThe rayon and rubber V-belt are widely used for power transmission. Such belts are made in two series: the standard V-belt and the high capacity V-belt. The belts can be used with short center distances and are made endless so that difficulty with splicing devices is avoided.First, cost is low, and power output may be increased by operating several belts side by side. All belts in the drive should stretch at the same rate in order to keep the load equally divided among them. When one of the belts breaks, the group must usually be replaced. The drive may be inclined at any angle with tight side either top or bottom. Since belts can operate on relatively small pulleys, large reductions of speed in a single drive are possible.Second，the included angle for the belt groove is usually from 34°to 38°.The wedging action of the belt in the groove gives a large increase in the tractive force developed by the belt.Third，pulley may be made of cast iron, sheet steel, or die-cast metal. Sufficient clearance must be provided at the bottom of the groove to prevent the belt from bottoming as it becomes narrower from wear. Sometimes the larger pulley is not grooved when it is possible to develop the required tractive force by running on the inner surface of the belt. The cost of cutting the grooves is thereby eliminated. Pulleys are on the market that permit an adjustment in the width of the groove. The effective pitch diameter of the pulley is thus varied, and moderate changes in the speed ratio can be secured.Chain DrivesThe first chain-driven or “safety” bicycle appeared in 1874, and chains were used for driving the rear wheels on early automobiles. Today, as the result of modern design and production methods, chain drives that are much superior to their prototypes are available, and these have contributed greatly to thedevelopment of efficient agricultural machinery, well-drilling equipment, and mining and construction machinery. Since about 1930 chain drives have become increasingly popular, especially for power saws, motorcycle, and escalators etc.There are at least six types of power-transmission chains; three of these will be covered in this article, namely the roller chain, the inverted tooth, or silent chain, and the bead chain. The essential elements in a roller-chain drive are a chain with side plates, pins, bushings (sleeves), and rollers, and two or more sprocket wheels with teeth that look like gear teeth. Roller chains are assembled from pin links and roller links. A pin link consists of two side plates connected by two pins inserted into holes in the side plates. The pins fit tightly into the holes, forming what is known as a press fit. A roller link consists of two side plates connected by two press-fitted bushings, on which two hardened steel rollers are free to rotate. When assembled, the pins are a free fit in the bushings and rotate slightly, relative to the bushings when the chain goes on and leaves a sprocket.Standard roller chains are available in single strands or in multiple strands, In the latter type, two or more chains are joined by common pins that keep the rollers in the separate strands in proper alignment. The speed ratio for a single drive should be limited to about 10∶1; the preferred shaft center distance is from 30 to 35 times the distance between the rollers and chain speeds greater than about 2500 feet (800 meters) per minute are not recommended. Where several parallel shafts are to be driven without slip from a single shaft, roller chains are particularly well suited.An inverted tooth, or silent chain is essentially an assemblage of gear racks, each with two teeth, pivotally connected to form a closed chain with the teeth on the inside, and meshing with conjugate teeth on the sprocket wheels. The links are pin-connected flat steel plates usually having straight-sided teeth with an included angle of 60 degrees. As many links are necessary to transmit the power and are connected side by side. Compared with roller-chain drives, silent-chain drives are quieter, operate successfully at higher speeds, and can transmit more load for the same width. Some automobiles have silent-chain camshaft drives.Bead chains provide an inexpensive and versatile means for connecting parallel or nonparallel shafts when the speed and power transmitted are low. The sprocket wheels contain hemispherical or conical recesses into which the beads fit. The chains look like key chains and are available in plain carbon and stainless steel and also in the form of solid plastic beads molded on a cord. Bead chains are used oncomputers, air conditioners, television tuners, and Venetian blinds. The sprockets may be steel, die-cast zinc or aluminum, or molded nylon.Machine Parts (II)FastenerFasteners are devices which permit one part to be joined to a second part and, hence, they are involved in almost all designs.There are three main classifications of fasteners, which are described as follows：(1) Removable. This type permits the parts to be readily disconnected without damaging the fastener. An example is the ordinary nut-and-bolt fastener.(2) Semi permanent. For this type, the parts can be disconnected, but some damage usually occurs to the fastener. One such example is a cotter pin.(3) Permanent. When this type of fastener is used, it is intended that the parts will never be disassembled. Examples are riveted joints and welded joints.The importance of fasteners can be realized when referring to any complex product. In the case of the automobile, there are literally thousands of parts which are fastened together to produce the total product. The failure or loosening of a single fastener could result in a simple nuisance such as a door rattle or in a serious situation such as a wheel coming off. Such possibilities must be taken into account in the selection of the type of fastener for the specific application.Nuts, bolts, and screws are undoubtedly the most common means of joining materials. Since they are so widely used, it is essential that these fasteners attain maximum effectiveness at the lowest possible cost. Bolts are, in reality, carefully engineered products with a practically infinite use over a wide range of services.An ordinary nut loosens when the forces of vibration overcome those of friction. In a nut and lock washer combination, the lock washer supplies an independent locking feature preventing the nut from loosening. The lock washer is useful only when the bolt might loosen because of a relative change between the length of the bolt and the parts assembled by it. This change in the length of the bolt can be caused by a number of factors-creep in the bolt, loss of resilience, difference in thermal expansion between the bolt and the bolted members, or wear. In the above static cases, the expanding lock washer holds the nut under axial load and keeps the assembly tight. When relative changes are caused by vibration forces, the lock washer is not nearly as effective.Rivets are permanent fasteners. They depend on deformation of their structure for their holding action. Rivets are usually stronger than the thread-type fastener and are more economical on a first-cost basis. Rivets are driven either hot or cold,depending upon the mechanical properties of the rivet material. Aluminum rivets, for instance, are cold-driven, since cold working improves the strength of aluminum. Most large rivets are hot-driven, however.ShaftVirtually all machines contain shafts. The most common shape for shafts is circular and the cross section can be either solid or hollow (hollow shafts can result in weight savings).Shafts are mounted in bearings and transmit power through such devices as gears, pulleys, cams and clutches. These devices introduce forces which attempt to bend the shaft; hence, the shaft must be rigid enough to prevent overloading of the supporting bearings. In general, the bending deflection of a shaft should not exceed 0.01 in. per ft. of length between bearing supports.For diameters less than 3 in., the usual shaft material is cold-rolled steel containing about 0.4 percent carbon. Shafts are either cold-rolled or forged in sizes from 3 in. to 5 in. .For sizes above 5 in. , shafts are forged and machined to size. Plastic shafts are widely used for light load applications. One advantage of using plastic is safety in electrical applications, since plastic is a poor conductor of electricity.Another important aspect of shaft design is the method of directly connecting one shaft to another. This is accomplished by devices such as rigid and flexible couplings.BearingA bearing can be defined as a member specifically designed to support moving machine components. The most common bearing application is the support of a rotating shaft that is transmitting power from one location to another. Since there is always relative motion between a bearing and its mating surface, friction is involved. In many instances, such as the design of pulleys, brakes, and clutches, friction is desirable. However, in the case of bearings, the reduction of friction is one of the prime considerations：Friction results in loss of power, the generation of heat, and increased wear of mating surfaces.The concern of a machine designer with ball bearings and roller bearings is fivefold as follows：(1) Life in relation to load; (2) stiffness, i.e. deflections under load;(3) friction; (4) wear; (5) noise. For moderate loads and speeds the correct selection ofa standard bearing on the basis of load rating will usually secure satisfactoryperformance. The deflection of the bearing elements will become important where loads are high, although this is usually of less magnitude than that of the shafts or other components associated with the bearing. Where speeds are high special cooling arrangements become necessary which may increase frictional drag. Wear is primarily associated with the introduction of contaminants, and sealing arrangements must be chosen with regard to the hostility of the environment.Notwithstanding the fact that responsibility for the basic design of ball bearings and roller bearings rests with the bearing manufacturer, the machine designer must form a correct appreciation of the duty to be performed by the bearing and be concerned not only with bearing selection but with the conditions for correct installation.The fit of the bearing races onto the shaft or onto the housings is of critical importance because of their combined effect on the internal clearance of the bearing as well as preserving the desired degree of interference fit. Inadequate interference can induce serious trouble from fretting corrosion. The inner race is frequently located axially by abutting against a shoulder. A radius at this point is essential for the avoidance of stress concentration and ball races are provided with a radius or chamfer to allow space for this.A journal bearing, in its simplest form, is a cylindrical bushing made of a suitable material and containing properly machined inside and outside diameters. The journal is usually the part of a shaft or pin that rotates inside the bearing.Journal bearings operate with sliding contact, to reduce the problems associated with sliding friction in journal bearings, a lubricant is used in conjunction with compatible mating materials. When selecting the lubricant and mating materials, one must take into account bearing pressures, temperatures and also rubbing velocities. The principle function of the lubricant in sliding contact bearings is to prevent physical contact between the rubbing surfaces. Thus the maintenance of an oil film under varying loads, speeds and temperature is the prime consideration in sliding contact bearings.Introduction to Machinery DesignMachinery design is either to formulate an engineering plan for the satisfaction of a specified need or to solve an engineering problem. It involves a range of disciplines in materials, mechanics, heat, flow, control, electronics and production.Machinery design may be simple or enormously complex, easy or difficult, mathematical or nonmathematical, it may involve a trivial problem or one of great importance. Good design is the orderly and interesting arrangement of an idea to provide certain results or effects. A well-designed product is functional, efficient, and dependable. Such a product is less expensive than a similar poorly designed product that does not function properly and must constantly be repaired.People who perform the various functions of machinery design are typically called industrial designers. He or she must first carefully define the problem, using an engineering approach, to ensure that any proposed solution will solve the right problem. It is important that the designer begins by identifying exactly how he or she will recognize a satisfactory alternative, and how to distinguish between two satisfactory alternatives in order to identify the better. So industrial designers must have creative imagination, knowledge of engineering, production techniques, tools, machines, and materials to design a new product for manufacture, or to improve an existing product.In the modern industrialized world, the wealth and living standards of a nation are closely linked with their capabilities to design and manufacture engineering products. It can be claimed that the advancement of machinery design and manufacturing can remarkably promote the overall level of a country’s industrization. Our country is playing a more and more vital role in the global manufacturing industry. To accelerate such an industrializing process, highly skilled design engineers having extensive knowledge and expertises are needed.Machinery ComponentsThe major part of a machine is the mechanical system. And the mechanical system is decomposed into mechanisms, which can be further decomposed into mechanical components. In this sense, the mechanical components are the fundamental elements of machinery. On the whole, mechanical components can be classified as universal and special components. Bolts, gear, and chains are the typical examples of the universal components, which can be used extensively in different machines across various industrial sectors. Turbine blades, crankshaft and aircraftpropeller are the examples of the special components, which are designed for some specific purposes.Mechanical Design ProcessProduct design requires much research and development. Many concepts of an idea must be studied, tried, refined, and then either used or discarded. Although the content of each engineering problem is unique, the designers follow the similar process to solve the problems.Recognition of NeedSometimes, design begins when a designer recognizes a need and decides to do something about it. The need is often not evident at, all; recognition is usually triggered by a particular adverse circumstance or a set of random circumstances, which arise almost simultaneously. Identification of need usually consists of an undefined and vague problem statement.Definition of ProblemDefinition of problem is necessary to fully define and understand the problem, after which it is possible to restate the goal in a more reasonable and realistic way than the original problem statement. Definition of the problem must include all the specifications for the thing that is to be designed. Obvious items in the specifications are the speeds, feeds, temperature limitations, maximum range, expected variation in the variables, and dimensional and weight limitations.SynthesisThe synthesis is one in which as many alternative possible design approaches are sought, usually without regard for their value or quality. This is also sometimes called the ideation and invention step in which the largest possible number of creative solutions is generated. The synthesis activity includes the specification of material, addition of geometric features, and inclusion of greater dimensional detail to the aggregate design.AnalysisAnalysis is a method of determining or describing the nature of something by separating it into its parts. In the process the elements, or nature of the design, are analyzed to determine the fit between the proposed design and the original design goals.EvaluationEvaluation is the final proof of a successful design and usually involves thetesting of a prototype in the laboratory. Here we wish to discover if the design really satisfies the needs.The above description may give an erroneous impression that this process can be accomplished in a linear fashion as listed. On the contrary, iteration is required within the entire process, moving from any step back to any previous step, in all possible combinations, and doing this repeatedly.PresentationCommunicating the design to others is the finial, vital presentation step in the design process. Basically, there are only three means of communication. These are the written, the oral, and the graphical forms. A successful engineer will be technically competent and versatile in all three forms of communication. The competent engineer should not be afraid of the possibility of not succeeding in a presentation. In fact, the greatest gains are obtained by those willing to risk defeat.Contents of Machinery DesignMachinery design is an important technological basic course in mechanical engineering education. Its objective is to provide the concepts, procedures, data, and decision analysis techniques necessary to design machine elements commonly found in mechanical devices and systems; to develop engineering students’ competence of machine design that is the primary concern of machinery manufacturing and the key to manufacture good products.Machinery design covers the following contents：Provides an introduction to the design process, problem formulation, safety factors.Reviews the material properties and static and dynamic loading analysis, including beam, vibration and impact loading.Reviews the fundamentals of stress and defection analysis.Introduces static failure theories and fracture-mechanics analysis for static loads.Introduces fatigue-failure theory with the emphasis on stress-life approaches to high-cycle fatigue design, which is commonly used in the design of rotation machinery.Discusses thoroughly the phenomena of wear mechanisms, surface contact stresses, and surface fatigue.Investigates shaft design using the fatigue-analysis techniques.Discusses fluid-film and rolling-element bearing theory and application.Gives a thorough introduction to the kinematics, design and stress analysis of spur gears, and a simple introduction to helical, bevel, and worm gearing.Discusses spring design including helical compression, extension and torsion springs.Deals with screws and fasteners including power screw and preload fasteners.Introduces the design and specification of disk and drum clutches and brakes.机械零件(I)齿轮齿轮是直接接触，成对工作的实体，在称为齿的凸出物的连续啮合作用下，齿轮能将运动和力从一个旋转轴传递到另一个旋转轴，或从一个轴传递到一个滑块(齿条)。

外文原文：The Introduction of the gearsIn the force analysis of spur gears, the forces are assumed to act in a single plane. We shall study gears in which the forces have three dimensions. The reason for this, in the case of helical gears, is that the teeth are not parallel to the axis of rotation. And in the case of bevel gears, the rotational axes are not parallel to each other. There are also other reasons, as we shall learn.Helical gears are used to transmit motion between parallel shafts. The helix angle is the same on each gear, but one gear must have a right-hand helix and the other a left-hand helix. The shape of the tooth is an involute helicoid. If a piece of paper cut in the shape of a parallelogram is wrapped around a cylinder, the angular edge of the paper becomes a helix. If we unwind this paper, each point on the angular edge generates an involute curve. The surface obtained when every point on the edge generates an involute is called an involute helicoid.The initial contact of spur-gear teeth is a line extending all the way across the face of the tooth. The initial contact of helical gear teeth is a point, which changes into a line as the teeth come into more engagement. In spur gears the line of contact is parallel to the axis of the rotation; in helical gears, the line is diagonal across the face of the tooth. It is this gradual of the teeth and the smooth transfer of load from one tooth to another, which give helical gears the ability to transmit heavy loads at high speeds. Helical gears subject the shaft bearings to both radial and thrust loads. When the thrust loads become high or are objectionable for other reasons, it may be desirable to use double helical gears. A double helical gear (herringbone) is equivalent to two helical gears of opposite hand, mounted side by side on the same shaft. They develop opposite thrust reactions and thus cancel out the thrust load. When two or more single helical gears are mounted on the same shaft, the hand of the gears should be selected so as to produce the minimum thrust load.Crossed-helical, or spiral, gears are those in which the shaft centerlines are neither parallel nor intersecting. The teeth of crossed-helical fears have point contact with each other, which changes to line contact as the gears wear in. For this reason they will carry outvery small loads and are mainly for instrumental applications, and are definitely not recommended for use in the transmission of power. There is on difference between a crossed helical gear and a helical gear until they are mounted in mesh with each other. They are manufactured in the same way. A pair of meshed crossed helical gears usually have the same hand; that is ,a right-hand driver goes with a right-hand driven. In the design of crossed-helical gears, the minimum sliding velocity is obtained when the helix angle are equal. However, when the helix angle are not equal, the gear with the larger helix angle should be used as the driver if both gears have the same hand.Worm gears are similar to crossed helical gears. The pinion or worm has a small number of teeth, usually one to four, and since they completely wrap around the pitch cylinder they are called threads. Its mating gear is called a worm gear, which is not a true helical gear. A worm and worm gear are used to provide a high angular-velocity reduction between nonintersecting shafts which are usually at right angle. The worm gear is not a helical gear because its face is made concave to fit the curvature of the worm in order to provide line contact instead of point contact. However, a disadvantage of worm gearing is the high sliding velocities across the teeth, the same as with crossed helical gears.Worm gearing are either single or double enveloping. A single-enveloping gearing is one in which the gear wraps around or partially encloses the worm.. A gearing in which each element partially encloses the other is, of course, a double-enveloping worm gearing. The important difference between the two is that area contact exists between the teeth of double-enveloping gears while only line contact between those of single-enveloping gears. The worm and worm gear of a set have the same hand of helix as for crossed helical gears, but the helix angles are usually quite different. The helix angle on the worm is generally quite large, and that on the gear very small. Because of this, it is usual to specify the lead angle on the worm, which is the complement of the worm helix angle, and the helix angle on the gear; the two angles are equal for a 90-deg. Shaft angle.When gears are to be used to transmit motion between intersecting shaft, some of bevel gear is required. Although bevel gear are usually made for a shaft angle of 90 deg. They may be produced for almost any shaft angle. The teeth may be cast, milled, or generated. Only the generated teeth may be classed as accurate. In a typical bevel gearmounting, one of the gear is often mounted outboard of the bearing. This means that shaft deflection can be more pronounced and have a greater effect on the contact of teeth. Another difficulty, which occurs in predicting the stress in bevel-gear teeth, is the fact the teeth are tapered.Straight bevel gears are easy to design and simple to manufacture and give very good results in service if they are mounted accurately and positively. As in the case of squr gears, however, they become noisy at higher values of the pitch-line velocity. In these cases it is often good design practice to go to the spiral bevel gear, which is the bevel counterpart of the helical gear. As in the case of helical gears, spiral bevel gears give a much smoother tooth action than straight bevel gears, and hence are useful where high speed are encountered.It is frequently desirable, as in the case of automotive differential applications, to have gearing similar to bevel gears but with the shaft offset. Such gears are called hypoid gears because their pitch surfaces are hyperboloids of revolution. The tooth action between such gears is a combination of rolling and sliding along a straight line and has much in common with that of worm gears.中文译文：齿轮简介在直齿圆柱齿轮的受力分析中，是假定各力作用在单一平面的。

外文原文GearsGears are vital factors in machinery ,which are uses to transmit power or motion from one shaft to another .They may be used only to transmit motion from one part of a machine to another,or they may be used to change the speed or the torque of one shaft with with relation to another.One of the first mechanism invented using gears wad the clock.In fact,a clock is little more than a train of gears.Considerable study and research have been made on gears in recent years because of their wide use under exacting conditions.They have to transmit heavier loads and run at high speeds than ever before.The engineers and the machinists all consider gearing the prime element in nearly all classes of machinery.Super GearsSpur gears will be considered first for several reasons.In the first place ,they are simplest and the least expensive of gears and they may be used to transmit power between parallel shafts,also,spur gears definitions are usually applicable to other types .It is important go understand the following definitions,since they are important factors in the design of any equipment utilizing gears.Diametric PitchThe number of teeth per inch of pitch cirle diameter .The diameter pitch is usually an integer .A small number for the pitch implies a large tooth size.Meshing spur gears must have the same diameter pitch .The speed ratio is based on the fact that meshing gears may have different-sized pitch circles and hence different number of teeth.Circular PitchThe distance from a point on one tooth to the corresponding point on an adjacent tooth ,measrued along the pitch circle.This is a liner dimension and thus bas liner units.Pitch CircleThe circle on which the ratio of the gear set is based,when two gears are meshing ,the two pitch circles must be exactly tangent if the gears are to function properly.The tangency point is known as the pitch point. Pressure AngleThe angle between the line of action and a line perpendicular to the centerlines of the two gears in mesing .Pressure Angles for spur gears are usually 14.5 or 20 degrees,although other values can be used.Meshing gears must have the same pressure angles.In the case of a rack,the teeth have the straight sides inclined at an angle corresponding to the pressure angle.Base CircleA circle tangent to the line of action (or pressure line ) .The base circle is the imaginary circle about which an involutes cure is developed .Most spur gears follow an involutes cure from the base circle to the top of the tootch,this cure can be visualized by observing a point on a taut cord an it is unwound from a cylinder .In a gear ,the cylinder is the best circle.AddendumThe radial distance form the pitch circle to the top of the tooth . DedendumThe radial distance from file pitch circle to the root of the tooth. ClearanceThe difference between the addendum and the addendum.Face WidthThe width of the tooth measured axially.FaceThe surface between the pitch circle and the top of the tooth. FlankThe surface between the pitch circle and the bottom of the tooth. Helical GearsThese gears have their tooth element at an angle or helix to the axis of the gear.They are more difficult and expensive to make than spur gears,but are quieter and stronger. They may be used to transmit power between parallel shafts at an angle to each in the same or different planes.Herringbone GearsA herringbone gear is equivalent to a right-hand and a left-hand helical gear placed side by side.Because of the angle of the tooth,helical gears create considerable side thrust on the shaft. A herringbone gear corrects this thrust by neutralizing it ,allowing the use of a small thrust bearing instead of a large one and perhaps eliminating one altogether.Often a central groove is made round the gear for ease in machining.Bevel GearsBevel gears are used to connect shafts, which are not parallel to each ually the shafts are 90 deg.To each other, but they may be more or less than 90 deg.The two meshing gears may have the same number of teeth for the purpose of changing direction of motion only,or they may have a different number of teeth for the purpose of changing both speed and direction .The faces of the teeth lie on the surface of the frustum of a cone,therefore the teeth elements are not parallel to each other it can be seen that this lack of parallelism creates a machining problem so that two passes with a tool must be made.The tooth elements may be straight or spiral ,so that we have plain anti spiral evel gears.Worm and Worm GearsA worm-and-worm-gear combination is used chiefly where it is desired to obtain a high gear reduction in a limited space,normally the worm drivers the worm gear and is not reversible ,that is to say,the worm gear can not drive the worm.Most worms can be rotated in either direction,clockwise or counterclockwise.RacksA rack is a gear with an infinite radius,or a gear with its perimeter stretched out into a straight line.It is used to change reciprocating motion to rotary motion or vice versa.A lathe rack and pinion is a good example of this mechanism.Various materials are used in manufacturing gears .Usually,the materials selected depends on the method used for making the gear and the application to which it will be put.Gears can be cast,cut,or extruded.Typical materials include cast iron,cast steel,plain carbon steel,alloy steel aluminum,phosphor bronze,laminated phonetics,and nylon.中文翻译齿轮齿轮是机器中的动力元件,用来传递轴与轴之间的运动及动力。

附录GEARSGears transmit power and motion between moving pasts. Positive transmission of power is accomplished by projections or teeth on the circumference of the gear . There is no slippage as with friction and belt drives , a feature most machinery requires ,because exact speed ratios are essential .Friction drives are used in industry ,where high speeds and light loads are required and where loads subject to impact are transmitted.When the teeth are built up on the circumference of two rolling disks in contact, recesses must be Provided between the teeth are developed is known as the pitch circle .It is an imaginary circle with the same diameter as a disk that would cause the same relative motion as the gear. All gear design calculations are based on the diameter of the pitch circle. A portion of a gear is shown in Figure 22.13.Gear NomenclatureThe system of gearing used in the United States is known as the involutes system, because the profile of a gear tooth is principally an involutes curve. An involutes is a curve generated on the circle, the normal of which are all tangent to this circle. The method of generating involutes is shown in Figure 22.14. Assume that a string having a pencil on its end is wrapped around a cylinder. The curve described by pencil as the string is unwound is an involutes, and the cylinder on which it is wound is known as the base circle. The portion of the gear tooth from the base at point a in the figure to the outside diameter at point c is an involutes curve and is the portion that contacts other teeth.. From point b topoint the profile of the base circle on which the involutes is described is inside the pitch circle and is dependent on the angle of thrust of the dear teeth. The relationship existing between the diameter of the pitch circle, D, is Db = Dcosθwhere Db = diameter of base circle θ=Angle of thrust between gear tooth.The two commonsystems have their thrust angles or lines of action at 141/2︒and 20︒.Figure 22.13 Nomencla ture for Involute spur gearOther angles are possible, but with larger angles the radial force component tending to force the gears apart becomes greater. If a common tangent is drawn to the pitch circles of two meshing gears. The base circle on which the involutes are drawn are tangent to the line of action.Most gears transmitting power use the 200, full-deep, involutes tooth form. These gears have the same tooth proportion as the 141/20 full–depth involutes but are stronger at their base because of greater thickness. The 200, fine –pitch involutes gears are-similar to the regular 200 involutes and are made in sizes ranging from 20 to 200 diametral pitch. These gears are used primarily for transmitting motion rather the power. The 200 stub tooth gear has smaller tooth depth than the 200. Full –depth gear and is consequently stronger. Involutes gears fulfill all laws of gearing and have the advantage over some other curves in that the contact action is affected by slight variation of gear center distance.Figure 22.14 Mothod of genera an Involute tooth surfaceThe nomenclature of a gear tooth is illustrated in Figure 22.13. the principal definitions and tooth parts for standard 141/20 and 200 involutes gears are discussed here.The addendum of a tooth is the radial distance from the pitch circle to the outside diameter of addendum circle. Numerically, it is equal to 1 divided by the diametral pitch P.The addendum is the radial distance from the pitch circle to the root or addendum circle. It is equal to the addendum plus the tooth clearance.Tooth thickness is the thickness of the tooth measure on the pitch circle. For cut gears the tooth thickness and tooth space are equal. Cast gears are provided with some backlash, the difference between the tooth thickness and tooth space measured on the pitch circle.The face of a gear tooth is that surface lying between the pitch circle and the addendum circle.The flank of a gear tooth is that surface lying between the pitch circle and the root circle.Clearance is a small distance provided so that the top of a meshing tooth will not touch the bottom land of the other gear as it passes the line of centers.Table 22.2gives the proportions of standard 141/200 involutes gears expressed in term of diametral pitch P and number of teeth N.Table 22.2 American Gear Manufactures Association Standard for Involute GearingPitch of GearsThe circuit pitch p is the distance from a point on one tooth to the corresponding point on an adjacent tooth, and is measured on the pitch circle. Expressed as an equation.Metrical gearing is based on the module(mod) instead of the diametral pitch p, as in the English system. The basic metric module formula is mod =D/N=amount of pitch diameter per tooth =millimeters per tooth measured on the pitch diameter. Also, mod=1/p is expressed in millimeters. Also, mod p=25.4.P = πD/N where D = diameter of the pitch circleN = number of teethThe diametral pitch p, often referred to as the pitch of a gear is the ratio of the number of teeth to the pitch diameter. It may be expressed by the following equation: P = N/DUpon multiplying these two equations the following relationship between circular and diametral pitch results.Hence,knowing the value of either pitch we may obtail the other by dividing into π.Gears and gear cutters are standardized according to diametral pitch. This pitch can be expressed in even figures or fractions. Circular pitch, being an actual distance,it is expressed in inches and fractions of an inch. A 6-inth gear (6diametral pitch) is one that has 6teeth per inch of pitch diameter . If the pitch diameter is 3 inch, the number of teeth is 3 x 6 or 18.The outside diameter of the gear is equal to the pitch diameter plus twice the addendum distance or 3 in.+2 x 1/6,which is 3.333in.Any involutes gear of a given diametral pitch will mesh properly with a gear of any other size of the same diametral pitch. However, in cutting gears of various diameters a slight difference in the cutter is necessary to allow for the change in curvature of the involutes as the diameter increases. The extreme case would be a rack tooth ,which would have a straight line as the theoretical tooth profile. For practical reasons the number of teeth in an involutes gear should not be less than 12.Gear speedThe speeds in rooms ,s and S, of two meshing gears vary inversely with both the pitch diameter and the number of teeth .This may be expressed as follows:Figure 22.15 Nomenclature for meshing gear and pinons/S = D/d =T/twhere Dand d represent pitch diameter as included as indicated in Figure 22.15.T and t represent number of teeth on the gear and pinion.Center distance : L = (D+d)/2The speed ratio for a worm gear set depends on the number of teeth on the gear and the lead of the worm. For a single=threaded worm the ratio isRpm worm/rpm gear = T/tKinds of gearsThe gears most commonly used are those that transmission power between two parallel shafts. Such gears having their tooth elements parallel to the ratating shaftsare known as spur gears, the smaller of the two being known as a pinion (Figure 22.15).If the elements of the teeth are twisted or helical,as known in figure 22.16B,they are known as helical gears. These gears amay be for connecting shafts that are at an angle in the same or different planes. Helical gears are smooth acting because there is always more than one tooth in contact. Some power is lost because of end thrust, and provision must be made to compensate for this thrust in the bearings. The herringbone gear is equivalent to two helical gears, one having right-hand and the other a left-hand helix.Figre 22.17 All elements of straight bevel converge at the one opex of the gears Usually, when two shafts are in the same plane but at an angle with one another, a bevel gear is used. Such a gear is similar in appearance to the frustum of a cone having all the elements of the teeth intersecting at a point, as shown in Figure 22.17. Bevel gears are made with either straight or spiral teeth. When the shafts are at right angles and the two bevel gears are the same size, they are known as miter gears (figure 22.16A). Hypoid gears, an interesting modification of bevel gears shown as Figure 22.16F, have their shaft at right angles by they do not intersect as do the shaft for bevel gears. Correct teeth for these gears are difficult to construct, although a generating process has been developed that produces satisfactory teeth. Zero gears (Figure 22.16D)have curved teeth but have a zero helical angle. They are produced on machines that cut spiral bevels and hypoids. Worm gearing is used where a large speed reduction is desired. The small driving gear is called a worm and the driving gear is called a worm and the driven gear a wheel. The worm resembles a large screw and is set in close to the wheel circumference, the teeth of the wheel being curving toconform to the diameter of the worm. The shafts for such gears are at right angles but not in the same plane. These gears are similar to helical gears in their application, but differ considerably in appearance and method of manufacture. A worm gear set is shown in Figure 22.16C.Rack gears, which are straight and have no curvature, represent a gear of infinite radius and are used in feeding mechanisms and for reciprocating. They may have either straight or helical teeth. If the rack is bent in the form of a circle, it becomes a bevel gear having a cone apex angle of 180ºknown as crown gear. the teeth all converge at the center of the disk and mesh properly with a bevel gear of the same pitch. A gear with internal teeth, known as an annular gear, can be cut to mesh with either a spur or bevel gear, depending on whether the shafts are parallel or intersecting.Methods of Making GearsMost gears are produced by some machining process. Accurate machine work is essential for high-speed, long-wearing, quite-operating gears. Die and investment casting of gears has proved satisfactory, but the materials are limited to low-temperature-melting metals and alloys. Consequently, these gears do not have the wearing qualities of heat-treated steel gears. Stamping though reasonably accurate, can be used only in making thin gears from sheet metal.Commercial methods employed in producing gears are summarized as follows: A: Casting 1.sand casting 2.Die casting 3.Precision and investment castingB: StampingC: Machining 1.Formed-tooth process a. From cutter in milling machine b. From cutter in broaching machine c. From cutter in shaper 2.Template process 3.Cutter generating process a. cutter gear b. Hobbing c. Rotary cutter d. Reciprocating cutters simulating a rackD: Power metallurgyE: ExtrudingF: RollingG: GrindingH: Plastic moldingForm Tooth ProcessA formed milling cutter, as shown in Figure22.18,is commonly used for cutting a spur gear. Such a cutter used on a milling machine is formed according to the shape of the tooth space to de removed. Theoretically, there should be a different-shape cutter for each size gear of a given pitch as there is a slight change in the curvature of the involutes. However, one cutter can be used for several gears having different numbers of teeth without much sacrifice in their operation. Each pitch cutter is made in eight slightly varying shapes to compensate for this change.They vary from no.1, which is used to cut gears from 135 teeth to a rack, to no.8, which cuts gears having 12 or 13 teeth. The eight standard involutes cutters are listed in Table 22.3.Setup of a milling machine to cut spur gears are illustrated in Figure 22.18. A discussion of this process is given the chapter on milling is an accurate process for cutting spur, helical, and worm gears. Although sometimes used for bevel gears, the process is not accurate because of the gradual change in tooth thickness. When used for bevel gears at least two cuts are necessary for each tooth space. The usual practice is to take one center cut of proper depth and about equal to the space at the small end of the tooth. Two shaving cuts are then on each side of the tooth space to give the tooth its proper shape.Figure 22.18 Setup for cutting a spir gear on a milling machineTable 22.3 Standard Involute cuttersNo.1135 teeth to a rackNo.255 to 134 teethNo.335 to 54 teethNo.426 to 34 teethNo.521 to 25 teethNo.617 to 20 teethNo.714 to 16 teethNo.812 to 13 teethThe formed-tooth principle may also be utilized in a broaching machine by making the broaching tool conform to the teeth space. Small internal gears can be completely cut in one pass by having a round broaching tool made with the same number of cutters as the gear has teeth. Broaching tool is limited to large-scale production because of the cost of cutters.齿轮运动部件之间的能量和运动由齿轮来传递。

原文：题目Gear Manufacturing MethodsGears, defined as toothed members transmitting rotary motion from one shaft to another, are among the oldest devices and inventions of man. In about 2006 B.C., the Chinese are known to have used a chariot incorporating a complex series of gears. Aristotle, in the fourth century B.C., wrote of gears as if they were commonplace. In the fifteenth century A.D., Leonardo da Vinci designed a multitude of devices incorporating many kinds of gears.Gears provide a positive-ratio driver for transmitting rotary motion from one shaft to another. Gear types are determined largely by the disposition of the shafts; in addition, certain types are better suited than others for large speed changes. This means that if a specific disposition of the shafts is required, the type of gear will more or less be fixed. On the other hand, if a required speed change demands a certain type, the shaft positions will also be fixed. If the shafts are parallel, any of three types may be used：spur, helical, or herring-home gear. Spiral gears are used to connect two shafts that are nonparallel and nonintersecting. Worm gears are used where high ratios are desired and where the shafts are nonintersecting and at right angle. Bevel gears are often used when two shafts are at right angles other than 90 degrees. Spiral bevel gears can be used in the same applications as straight-tooth bevel gears; the spiral bevel gears are capable of higher speeds and quieter operation. Hypoid gears are similar to spiral bevel gears, except that the extensions of the centerlines do not intersect. Rack-and-pinion drives are used where the rotary motion of one part must be transformed into translating motion of the other part, or vice versa. The incorporation of some of these types into gear trains constitutes an important phase of design.Tooth profiles. The contacting surfaces of gear teeth must be aligned in such a way that the drive is positive; i.e., the load transmitted must not depend on frictional contact. As shown in the treatment of direct contact bodies, this requires that the common normal to the surfaces not to pass through the pivotal axis of either the driver or the follower. As it is known as direct contact bodies, cycloidal and involute profiles provide both a positive drive and a uniform velocity ratio; i.e., conjugate action.Basic relations. The smaller of a gear pair is called the pinion and the larger is the gear. When the pinion is on the driving shaft the pair acts as a speed reducer. When the gear drives, the pair is a speed increaser. Gears are more frequently used to reduce speed than to increase it.Among the various means of mechanical power transmission (including primarily gears, belts, and chains), gears are generally the most rugged and durable. Their power transmission efficiency is as high as 98 percent. On the other hand, gears are usually more costly than chains and belts. As would be expected, gears manufacturing costs increase sharply with increased precision-as required for the combination of high speeds and heavy loads, and for low noise levels. (Standard tolerances for various degrees of manufacturing precision have been established by the AGMA, American Gear Manufacturers Association.)Gear Manufacturing MethodsPlaning The shape of the space between gear teeth is complex and varies withthe number of teeth on the gear as well as tooth module, so most gear manufacturing methods generate the tooth flank instead of forming.Planing uses a reciprocating rack, stroking in the direction of the helix on a gear with a gradual generation of form as the rack effectively mils round the gear blank. The rack is relieved out of contact for the return stroke as in normal shaping or planing. It has the great advantage that the cutting tool is a simple rack with (nearly) straight sided teeth which can easily be ground accurately, This method is little used for high production because it is relatively slow in operation due to the high tool and slide mass; for jobbing purposes the slow stroking rate does not matter and low tool costs give an advantage where unusual sizes or profile modifications are required.Shaping Shaping is inherently similar to planing but uses a circular cutter instead of a rack and the resulting reduction in the reciprocating inertia allows much higher stroking speeds; modern shapers cutting car gears can run at cutting strokes per minute. The shape of the cutter is roughly the same as an involute gear but the tips of the teeth are rounded.The generating drive between cutter and workpiece does not involve a rack or leadscrew since only circular motion is involved. The tool and workpiece move tangentially typically0,5 mm for each stroke of the cutter. On the return stroke the cutter must be retracted about 1 mm to give clearance otherwise tool rub occurs on the backstroke and failure is rapid.The advantages of shaping are that production rates are relatively high and that it is possible to cut right up to a shoulder. Unfortunately, for helical gears, a helical guide is required to impose a rotational motion on the stroking motion; such helical guides cannot be produced easily or cheaply so the method is only suitable for long runs with helical gears since special cutters and guides must be manufactured for each different helix angle. A great advantage of shaping is its ability to cut annular gears such as those required for large epicyclic drives.Hobbing Hobbing, the most used metal cutting method, uses the rack generating principle but avoids slow- reciprocation by mounting many "racks" on rotating cutter. The "racks" are displaced axially to form a gashed worm.Metal removal rates are high since no reciprocation of hob or workpiece is required and so cutting speeds of 40 m/min can be used for conventional hobs and up to 150 m/min for carbide hobs. Typically with a 100 mm diameter hob the rotation speed will be 100 rpm and so a twenty tooth workpiece will rotate at 5 rpm. Each revolution of the workpiece will correspond to 0.75 mm feed so the hob will advance through the workpiece at about 4 mm per minute. For car production roughing multiple start hobs can be used with coarse feeds of3 mm per revolution so that 100 rpm on the cutter, a two-start hob and a 20 tooth gear will give a feed rate of 30 mm/min.Broaching Broaching is not usually used for helical gears but is useful for internal spur gears; the principle use of broaching in this context is for internal splines which cannot easily be made by any other method. As with all broaching the method is only economic for large quantities since setup costs are high.Broaching gives high accuracy and good surface finish but like all cuttingprocesses is limited to "soft" materials which must be subsequently case-hardened or heat treated, giving distortion.Shaving Shaving is used as finishing processes for gears in the "soft" state. The objective is to improve surface finish and profile by mating the roughed-out gear with a "cutter" which will improve form.A shaving cutter looks like a gear which has extra clearance at the root (for swarf and coolant removal) and whose tooth flanks have been grooved to give cutting edges. It is run in mesh with the rough gear with crossed axes so that there is in theory point contact with a relative velocity along the teeth giving scraping action. The shaving cutter teeth are relatively flexible in bending and so will only operate effectively when they are in double contact between two gear teeth. The gear and cutter operate at high rotational speeds with traversing of the workface and about 100 micron of material is removed. Cycle times can be less than half a minute and the machines are not expensive but cutters are delicate and difficult to manufacture.Grinding Grinding is extremely important because it is the main way hardened gears are machined. When high accuracy is required it is not sufficient to pre-correct for heat treatment distortion and grinding is then necessary: The simplest approach to grinding is form grinding. The wheel profile is dressed accurately to shape using single point diamonds which are controlled by templates cut to the exact shape required. The profiled wheel is then reciprocated axially along the gear, when one tooth shape has been finished, involving typically 100 micron metal removal, the gear is indexed to the next tooth space. This method is fairly slow but gives high accuracy consistently. Setting up is lengthy because different dressing templates are needed if module, number of teeth, helix angle, or profile correction is changed.The fastest grinding method uses the same principle as hobbing but replaces a gashed and relieved worm by a grinding wheel which is a rack in section. Only single start worms are cut on the wheel but gear rotation speeds are high, 100 rpm typically, so it is difficult to design the drive system to give accuracy and rigidity. Accuracy of the process is reasonably high although there is a tendency for wheel and workpiece to deflect variably during grinding so the wheel form may require compensation for machine deflection effects. Generation of a worm shape on the grinding wheel is a slow process since a dressing diamond must not only form the rack profile but has to move axially as the wheel rotates. Once the wheel has been trued, gears can be ground rapidly until redressing is required. This is the most popular method for high production rates with small gears.译文：题目齿轮制造方法齿轮，定义为把一个旋转运动传输到另一个的主体，是人类最早的发明和装置。

毕业设计（论文）外文参考文献译文及原文系部机械电气学部专业机械设计制造及其自动化年级 200x级班级名称机械设计1班学号 x x学生姓名 xxx 指导教师 xxxxx年x 月目录1 Representative Strcture of Injection Mol译文 (3)外文 (4)2 Number of Mold Cavities译文 (5)外文 (7)注射模的典型结构用于热塑性塑料注射成型的模具通常是溢料式模具，因为与传递模塑成型一样，在注射成型中，不需要额外的载料空间。

但是，模具设计的基本类型有多种变化。

所有材料最常使用的设计是两板模设计。

型腔装在第一个模板上，凸模装载第二个模板上。

主流道衬套并入定模的模板中。

按照这种安排，就有可能使用直接中心浇口，使塑料进入单腔模或者是多腔模的分流道系统中。

在大多数情况下，凸模、顶出装置以及分流道系统在动模中。

虽然为了符合特定要求会有许多变化，但是这是注射模的基本设计。

三板模设计的特点是具有包含型腔的第三个可移动的模板，因此对于多型腔操作，允许中心或偏置浇口进入每一个型腔。

模具打开时有两次分模，一个塑件的脱模，另一个是去除分流道和主流道凝料。

通过压力机常规功能不能成型的的带镶嵌件、螺纹和取芯的模塑件，要求在模具中安装分离的或零散的部件或者型芯。

这些零撒的部件随着塑件被顶出。

每一个生产周期后，这些部件必须与塑件分离，并重新安装在模具中。

因此使用复制的部件以高效生产。

液压缸或气缸被安装在模具中以抽出侧型芯部件。

在模具设置料导柱，就能完成有角度侧抽芯，而不需要高成本的零散部件。

有几种方法可用于旋松塑件上的内螺纹或外螺纹：为了提高生产率，常常使用价格相对较低的长行程的液压油缸驱动齿轮齿条机构进行自动脱螺纹。

其他脱螺纹的方法包括使用通过双动油缸驱动的齿轮齿条或摩擦型弧刷。

塑件的内部凸凹可以通过带料度的型芯（成型杆）成型，型芯的移动由将金属型芯与塑件分离的顶出杆驱动。

General transformation of multi-axis drilling machine drillingmachinAt present, China's small and medium enterprises in product quality and production efficiency are the need for a new increase. But the processing means is far from sufficient. Many small and medium enterprises with their actual technical state of equipment improvements,through strengthening its own.In order to mon drilling for single-axis machine tools, but the installation will become a multi-axis multi-axle box of the drill, transformation into a multi-axis drilling, we could greatly shorten the processing time, improve production efficiency.Application of multi-axis machining:According to statistics, in general machine tools in the workshop in general, the average cutting time rarely exceeds 15% of total working hours. The remaining time is plug-in, loading and unloading the workpiece, exchange tools, operation tools, measurements, and clear the iron filings and so forth. Although the use of CNC machine tools can improve 85%, but the purchase of costly. In some cases, even if the high productivity, but the processing of the same components, the cost is not necessarily lower than the average machine. Therefore must be more to shorten the processing time. Different processing methods have different characteristics, the drilling process, the multi-axis machining is a small investment to increase productivity through effective measures.The advantages of multi-axis machining:Although it is not the first in automatic multi-axis adjustable long line applications, but only limited to high-volume production. Even with the adjustable multi-axis head expanded the scope of use is still far from being able to meet the volume is small, hole complex requirements. In particular, as industrial development, large and complex multi-axis machining is even more compelling. For example, large-scale nuclear power plants in the water-wall tube plate condenser has 15000 ψ20 holes, if radial drilling machine processing, and simply drilling holes and countersink countersunk head is necessary to 842.5 hours, while also crossed hours 151.1 hours. However, if the 8-axis CNC machining floor drilling, drilling countersink holes as long as 171.6 hours, crossed is also simple, as long as 1.9 hours. Therefore, the use of numerical control of two axis, so that proper alignment tool processing location, combined with multi-axis machining can not only expand the range of processing, but also on the basis of improving the accuracy can greatly enhance the work efficiency, easy to quickly create original processing parts. Some analysis of large high-speed diesel engine with 30 kinds of box-shaped rod-shaped parts of the more than 2,000 drilling operations, 40% could be the automatic replacement of machines using two-axis spindle box, three-axis or four-axis multi-axis machining head, the average can be reduced 20% of theprocessing time. Machine Tool Exhibition in Paris in 1975 also reflected the multi-axis machining using more and more the trend.Multi-axis machining equipment:Multi-axis machining is the same time in a feed processing a number of holes or simultaneously in many of the same or different processing of a workpiece on each hole. This will not only shorten the cutting time and improve accuracy, reduce fixturing or positioning time, and in the CNC machine tool is not necessary to calculate the coordinates, reducing the number of character blocks and simplified programming. It can be processed using the following equipment: radial drilling vertical drilling, or upload multi-axis head, multi-axis drilling machine, multi-axis modular machine tool spindle box heart and automatic replacement of machines. May even be able to automatically adjust wheelbase by two or more of the spindle axle box, junction All CNC vertical and horizontal table two directions of movement, processing a variety of round or oval-shaped hole group of one or several steps. Now the status quo in this regard to make a profile.Multi-Axis Head:Transmission is from the main drive gear drive with two kinds of universal joint couplings. This is our familiar. Former is more efficient, simple structure, which is easy to adjust wheelbase. From the structure is concerned there is not adjustable and the adjustable two kinds. The former can not change the wheelbase,multi-use gear drive, only applies to high-volume production. Adaptability in order to expand its approval to develop a multi-axis adjustable head, in a certain range adjustable wheelbase. It is mainly mounted in a universal. Two. (1) there are two kinds of universal axis: alignment device with a spindle. Spindle mounted on adjustable bracket in an adjustable bracket can be T-shaped slot in the shell move, and the position in alignment with bolted. (2) with a tolerance of cylindrical spindle units. Set of fixed spindle hole with pieces of the same type template. The former applies to small batch and the rules of distribution of pore groups are artifacts (such as the hole groups in different diameter circle). The latter applies to a larger batch-type production of small quantities of turns, rigid better pitch accuracy is also high, but a different hole requires a different template.Multi-axis head can be mounted on vertical drilling-type radial drilling machine, press the drill itself with the various functions work. This multi-axis processing methods, due to drilling efficiency, range and accuracy of processing of the relationship between the use of limited scope.Multi-axle box:As also the first multi-axis as the production as a standard component. U.S. Secto's standard gear boxes, multi-axle box, etc. are not designed adjustable multi-axle box.32 kinds of specifications, process size from 300X300 mm to 600X1050 mm, the working-axis up to 60, and power up to 22.5 kilowatts. Romai factory adjustable multi-axlebox easy to adjust, as long as the gear should first be adjusted to the location near the pass and then connected with its adjustable-axis move to the correct location. Therefore, this structure changes as long as the template, will be able to pass a certain extent change the content of shoes, and can reach more than ordinary axle box smaller pitch.According to principles of the use of group processing the first multi-axle, or a combination of multi-axis machine tool is applicable to large and medium volume production. In order to process to get good results, need to consider the following points: (1) workpiece clamping simple, there is enough coolant away iron filings. (2) The fixture rigidity, processing, without deformation, dividing the right position. (3) the possibility of using the two group knives for a group to use, another set of grinding and adjustment, thereby reducing tool change downtime.(4) The use of quality tools to monitor whether the blunt tool, drill grinding to machine. (5) Dimensions can be detected immediately when the ultra-poor.Multi-axis drilling machine:This is a multi-axis machining to meet the requirements of the drill. Such as orientation, power, feed, speed and processing range. Displayed at the Paris Exhibition of multi-axis drilling machine with hydraulic multi-feed. Throughout its work, such as fast-forward through the bad, workers enter and clear the iron filings are all automatically. It is noteworthy that the majority of agencies with separate variable speed, so that one group can adapt to the different pore size hole processing needs. 1.2.4 automatic replacement machine tool spindle box .5In order to rationalize the needs of small and medium volume production in recent years the development of the automatic replacement of modular machine tool spindle box. (1) The automatic replacement spindle machine.Automatic replacement of rotary spindle machine tool spindle box at the top is a library, there are several non-adjustable hanging spindle box. Vertical and horizontal patch panel to the first series of good working procedures, so that the corresponding spindle box into the processing station, location and with the power connection tight, and then turn to the table with the workpiece spindle box below, upward mobility for processing. When the change processing object, as long as the exchange suspension spindle box, you can pass with different processes for different needs. (2) The multi-axis machine tool turret Turret to install more non-adjustable or universal coupling spindle box, turret can automatically switch to digital, and clamp the workpiece in the rotary table to feed motion. Through the rotary table can be a number of workpiece surface. Because the turret not be too big, so it is generally not exceed the median of workers 4-6. And the spindle box is also not too large. When the machining process more objects, size larger, it should automatically replace the machine tool spindle box fit, but its simple structure.(3) Automatic replacement of modular machine tool spindle box.It consists of automatic line or a combination of standard machine parts.Non-adjustable multi-axle box andpower box by home base in the horizontal, the spindle rotates, the entire case library fastening device to the system in the slip into the board. Library Headstock rotation and feed movement is based on standard routines of work. Headstock time for a few seconds. Clamping the hydraulic sub-degree rotary table so that each workpiece surface. Good fruit rotary table accompanied by discharging device, we can co-flow production automation. In the variable production system using this device, accompanied by the corresponding controller can obtain a complete processing system. (4) 8-axis CNC drill floor Large condenser water wall tube plate holes as many as 15,000, which linked together with the support plate processing. Diameter of 20 mm, hole depth 180 mm. Used inside the cooling pipe has a twist drill ,5-7 bar pressure, coolant directly into the cutting area is conducive to chip removal. And ground into a 90 ° drill point for the self-centering. Durable than regular twist drill, and a large quantity of feed. To shorten the processing time to 8-axis CNC machining floor.trends in multi-axis machining:Multi-axis machining high production efficiency, low investment and production preparation cycle is short, product modification, when a small loss of equipment. And as China's CNC technology, the scope of multi-axis machining will become the broad, processing efficiency will be improved.production tasks:A group of cast-iron joints have the same surface processing with multiple holes. In the general processing of vertical holes on the drill, usually a hole a hole drilling, production efficiency is low, use non-standard equipment, that is, combination of machining, production efficiency is high, but the large investment in equipment.However, the number of common vertical drilling machine to transform ordinary single-axis vertical multi-axis drilling machine after transformation, multi-axis drilling machine can simultaneously perform multiple hole drilling, expansion, hinges, and other processes.数控铣床用于螺旋斜面齿轮的表面雕刻加工摘要齿轮作为动力传动系统是现代精密机器中关键的组成部分，由于它的复杂和独特特点，齿轮经常被一些特定的机床设计制造，例如滚齿和插齿机器，这个论文中，我们打算用一个三轴数控铣床和一个旋转平台来制造螺旋斜面齿轮（齿轮生产中最复杂的一种），这其中包括(a)落选斜面齿轮的几何模型，(b)数控铣床的加工计划，(c)为四轴和四分之三轴控制的刀具走刀途径和执行计算程序，在这种方法下，实验性的切割已经做的很有效，这种方法是在四分之三轴的代码下控制的数控铣床下工作的。