汽车手动变速器外文文献翻译、中英文翻译、外文翻译

How Automatic Transmissions Workby Karim NiceIntroduction to How Automatic Transmissions WorkIf you have ever driven a car with an automatic transmission, then you know that there are two big differences between an automatic transmission and a manual transmission:There is no clutch pedal in an automatic transmission car.There is no gear shift in an automatic transmission car. Once you put the transmission into drive, everything else is automatic.Both the automatic transmission (plus its torque converter) and a manual transmission (with its clutch) accomplish exactly the same thing, but they do it in totally different ways. It turns out that the way an automatic transmission does it is absolutely amazing!Automatic Transmission Image GalleryIn this article, we'll work our way through an automatic transmission. We'll start with the key to the whole system: planetary gearsets. Then we'll see how the transmission is put together, learn how the controls work and discuss some of the intricacies involved in controlling a transmission.Just like that of a manual transmission, the automatic transmission's primary job is to allow the engine to operate in its narrow range of speeds while providing a wide range of output speeds.Photo courtesy DaimlerChryslerMercedes-Benz CLK, automatic transmission, cut-away modelWithout a transmission, cars would be limited to one gear ratio, and that ratio would have to be selected to allow the car to travel at the desired top speed. If you wanted a top speed of 80 mph, then the gear ratio would be similar to third gear in most manual transmission cars.You've probably never tried driving a manual transmission car using only third gear. If you did, you'd quickly find out that you had almost no acceleration when starting out, and at high speeds, the engine would be screaming along near the red-line. A car like this would wear out very quickly and would be nearly undriveable.So the transmission uses gears to make more effective use of the engine's torque, and to keep the engine operating at an appropriate speed.The key difference between a manual and an automatic transmission is that the manual transmission locks and unlocks different sets of gears to the output shaft to achieve the various gear ratios, while in an automatic transmission, the same set of gears produces all of the different gear ratios. The planetary gearset is the device that makes this possible in an automatic transmission.Let's take a look at how the planetary gearset works.Planetary Gearsets & Gear RatiosWhen you take apart and look inside an automatic transmission, you find a huge∙An ingenious planetary gearset∙ A set of bands to lock parts of a gearset∙ A set of three wet-plate clutches to lock otherparts of the gearset∙An incredibly odd hydraulic system that controlsthe clutches and bands∙ A large gear pump to move transmission fluidaroundThe center of attention is the planetary gearset. About the size of a cantaloupe, this one part creates all of the different gear ratios that the transmission can produce. Everything else in the transmission is there to help the planetary gearset do its thing. This amazing piece of gearing has appeared on HowStuffWorks before. You may recognize it from the electric screwdriver article. An automatic transmission contains two complete planetary gearsets folded together into one component. See How Gear Ratios Work for an introduction to planetary gearsets.From left to right: the ring gear, planet carrier, and two sun gearsAny planetary gearset has three main components:∙The sun gear∙The planet gears and the planet gears' carrier∙The ring gearEach of these three components can be the input, the output or can be held stationary. Choosing which piece plays which role determines the gear ratio for the gearset. Let's take a look at a single planetary gearset.One of the planetary gearsets from our transmission has a ring gear with 72 teeth and a sun gear with 30 teeth. We can get lots of different gear ratios out of this gearset.Also, locking any two of the three components together will lock up the whole device at a 1:1 gear reduction. Notice that the first gear ratio listed above is a reduction -- the output speed is slower than the input speed. The second is an overdrive -- the output speed is faster than the input speed. The last is a reduction again, but the output direction is reversed. There are several other ratios that can be gotten out of this planetary gear set, but these are the ones that are relevant to our automatic transmission. You can try these out in the animation below:So this one set of gears can produce all of these different gear ratios without having to engage or disengage any other gears. With two of these gearsets in a row, we can get the four forward gears and one reverse gear our transmission needs. We'll put the two sets of gears together in the next section.Compound Planetary GearsetThis automatic transmission uses a set of gears, called a compound planetary gearset, that looks like a single planetary gearset but actually behaves like two planetary gearsets combined. It has one ring gear that is always the output of the transmission, but it has two sun gears and two sets of planets.Let's look at some of the parts:How the gears in the transmission are put togetherLeft to right: the ring gear, planet carrier, and two sun gearsThe figure below shows the planets in the planet carrier. Notice how the planet on the right sits lower than the planet on the left. The planet on the right does not engage the ring gear -- it engages the other planet. Only the planet on the left engages the ring gear.Planet carrier: Note the two sets of planets.Next you can see the inside of the planet carrier. The shorter gears are engaged only by the smaller sun gear. The longer planets are engaged by the bigger sun gear and by the smaller planets.Inside the planet carrier: Note the two sets of planets.Automatic Transmission GearsFirst GearIn first gear, the smaller sun gear is driven clockwise by the turbine in the torque converter. The planet carrier tries to spin counterclockwise, but is held still by the one-way clutch (which only allows rotation in the clockwise direction) and the ring gear turns the output. The small gear has 30 teeth and the ring gear has 72, so the gear ratio is:Ratio = -R/S = - 72/30 = -2.4:1So the rotation is negative 2.4:1, which means that the output direction would be opposite the input direction. But the output direction is really the same as the input direction -- this is where the trick with the two sets of planets comes in. The first set of planets engages the second set, and the second set turns the ring gear; this combination reverses the direction. You can see that this would also cause the bigger sun gear to spin; but because that clutch is released, the bigger sun gear is free to spin in the opposite direction of the turbine (counterclockwise).Second GearT his transmission does something really neat in order to get the ratio needed for second gear. It acts like two planetary gearsets connected to each other with a common planet carrier.The first stage of the planet carrier actually uses the larger sun gear as the ring gear. So the first stage consists of the sun (the smaller sun gear), the planet carrier, and the ring (the larger sun gear).The input is the small sun gear; the ring gear (large sun gear) is held stationary by the band, and the output is the planet carrier. For this stage, with the sun as input, planet carrier as output, and the ring gear fixed, the formula is:1 + R/S = 1 + 36/30 = 2.2:1The planet carrier turns 2.2 times for each rotation of the small sun gear. At the second stage, the planet carrier acts as the input for the second planetary gear set, the larger sun gear (which is held stationary) acts as the sun, and the ring gear acts as the output, so the gear ratio is:1 / (1 + S/R) = 1 / (1 + 36/72) = 0.67:1To get the overall reduction for second gear, we multiply the first stage by the second, 2.2 x 0.67, to get a 1.47:1 reduction. This may sound wacky, but it works.Third GearMost automatic transmissions have a 1:1 ratio in third gear. You'll remember from the previous section that all we have to do to get a 1:1 output is lock together any two of the three parts of the planetary gear. With the arrangement in this gearset it is even easier -- all we have to do is engage the clutches that lock each of the sun gears to the turbine.If both sun gears turn in the same direction, the planet gears lockup because they can only spin in opposite directions. This locks the ring gear to the planets and causes everything to spin as a unit, producing a 1:1 ratio.OverdriveBy definition, an overdrive has a faster output speed than input speed. It's a speed increase -- the opposite of a reduction. In this transmission, engaging the overdrive accomplishes two things at once. If you read How Torque Converters Work, you learned about lockup torque converters. In order to improve efficiency, some cars have a mechanism that locksup the torque converter so that the output of the engine goes straight to the transmission.In this transmission, when overdrive is engaged, a shaft that is attached to the housing of the torque converter (which is bolted to the flywheel of the engine) is connected by clutch to the planet carrier. The small sun gear freewheels, and the larger sun gear is held by the overdrive band. Nothing is connected to the turbine; the only input comes from the converter housing. Let's go back to our chart again, this time with the planet carrier for input, the sun gear fixed and the ring gear for output.Ratio = 1 / (1 + S/R) = 1 / ( 1 + 36/72) = 0.67:1So the output spins once for every two-thirds of a rotation of the engine. If the engine is turning at 2000 rotations per minute (RPM), the output speed is 3000 RPM. This allows cars to drive at freeway speed while the engine speed stays nice and slow.ReverseReverse is very similar to first gear, except that instead of the small sun gear being driven by the torque converter turbine, the bigger sun gear is driven, and the small one freewheels in the opposite direction. The planet carrier is held by the reverse band to the housing. So, according to our equations from the last page, we have:Ratio = -R/S = 72/36 = 2.0:1So the ratio in reverse is a little less than first gear in this transmission.Gear RatiosThis transmission has four forward gears and one reverse gear. Let's summarize the gear ratios, inputs and outputs:After reading these sections, you are probably wondering how the different inputs get connected and disconnected. This is done by a series of clutches and bands inside the transmission. In the next section, we'll see how these work.Clutches and Bands in an Automatic TransmissionIn the last section, we discussed how each of the gear ratios is created by the transmission. For instance, when we discussed overdrive, we said:In this transmission, when overdrive is engaged, a shaft that is attached to the housing of the torque converter (which is bolted to the flywheel of the engine) is connected by clutch to the planet carrier. The small sun gear freewheels, and the larger sun gear is held by the overdrive band. Nothing is connected to the turbine; the only input comes from the converter housing.To get the transmission into overdrive, lots of things have to be connected and disconnected by clutches and bands. The planet carrier gets connected to the torque converter housing by a clutch. The small sun gets disconnected from the turbine by a clutch so that it can freewheel. The big sun gear is held to the housing by a band so that it could not rotate. Each gear shift triggers a series of events like these, with different clutches and bands engaging and disengaging. Let's take a look at a band.BandsIn this transmission there are two bands. The bands in a transmission are, literally, steel bands that wrap around sections of the gear train and connect to the housing. They are actuated by hydraulic cylinders inside the case of the transmission.One of the bandsIn the figure above, you can see one of the bands in the housing of the transmission. The gear train is removed. The metal rod is connected to the piston, which actuates the band.The pistons that actuate the bands are visible here.Above you can see the two pistons that actuate the bands. Hydraulic pressure, routed into the cylinder by a set of valves, causes the pistons to push on the bands, locking that part of the gear train to the housing.The clutches in the transmission are a little more complex. In this transmission there are four clutches. Each clutch is actuated by pressurized hydraulic fluid that enters a piston inside the clutch. Springs make sure that the clutch releases when the pressure is reduced.Below you can see the piston and the clutch drum. Notice the rubber seal on the piston -- this is one of the components that is replaced when your transmission gets rebuilt.One of the clutches in a transmissionThe next figure shows the alternating layers of clutch friction material and steel plates. The friction material is splined on the inside, where it locks to one of the gears. The steel plate is splined on the outside, where it locks to the clutch housing. These clutch plates are also replaced when the transmission is rebuilt.The clutch platesThe pressure for the clutches is fed through passageways in the shafts. The hydraulic system controls which clutches and bands are energized at any given moment.FROM: /automatic-transmission.htm自动变速器的工作原理耐斯·卡瑞姆介绍自动变速器的工作原理如果你驾驶过带有自动变速器的汽车，那么你一定知道手动变速器与自动变速器之间存在两个很大的区别：·自动变速器中没有离合器踏板·自动变速器中没有换档手柄，一旦让变速器传递动力，那么接下来的一切都是自动完成的了。

外文翻译Auto TransmissionFirst, an overview of automotive transmission and the development trendAutomobile available more than a century, especially from the mass production of motor vehicles and the automotive industry since the development of large, Car has been the economic development of the world for mankind to enter the modern life and have had a tremendous impact on the immeasurable, The progress of human society has made indelible contributions to the great, epoch-making set off arevolution. From From the vehicle as a power plant using internal combustion engine to start, auto transmission has become an important component. Is Generation is widely used in automotive reciprocating piston internal combustion engine with a small size, light weight, reliable operation and the use of The advantages of convenience, but its torque and speed range of smaller changes, and complex condition requires the use of motor vehicles Traction and the speed can be considerable changes in the scope. Therefore, its performance and vehicle dynamics and economy of There are large inter-contradictions, which contradictions of modern automotive internal combustion engine by itself is insoluble. Because Here, in the automotive power train set up the transmission and main reducer in order to achieve the purpose of deceleration by moment. Speed The main function of performance: ⑴ change gear ratio of motor vehicles, and expand the wheel drive torque and rotational speed of the Fan Wai, in order to adapt to constantly changing driving cycle, while the engine in the most favorable conditions within the scope of work; ⑵no change in the direction of engine rotation, under the premise of the realization of cars driving back; ⑶the realization of the free, temporary Interruption of power transmission, in order to be able to start the engine, idling, etc.. V ariable-speed drive transmission by the manipulation of institutions and agencies. Change the transmission ratio by way of transmission is divided into There are class-type, non-stage and multi-purpose three. Have class most widely used transmission. It uses gear drive, with a number of transmission ratio setting. Stepless transmission Continuously V ariable Transmission (CVT) transmission ratio of a certain The framework of multi-level changes may be unlimited, there is a common type of power and torque (dynamic fluid-type) and so on. Continuously V ariable Transmission Transmission development is the ultimate goal, because only it can make the most economical engine in working condition Can provide the best vehicle fuel economy and optimal power in order to provide the most comfortable By the feeling. Today's CVT is a typical representative of the CVTand IVT, however as a result of the reliability of Poor, non-durable materials and high cost issues, development is not very good. Comprehensive refers to transmission torque converter and the mechanical components have the level of transmission variable hydraulic mechanical Speed, the transmission ratio can be between the maximum and minimum range of a few discontinuous change for no class, but its Significantly lower transmission efficiency than the efficiency of gear drives. 2 By manipulation, transmission control type can be divided into mandatory, automatic and semi-automatic control to manipulate three - Species . Mandatory on the driver to manipulate the direct transmission gear shift control for the majority of motor vehicles used Also known as Manual Transmission Manual Transmission (MT). Automatic transmission control selection of the transmission ratio (transmission) is carried out automatically. Just add the driver to manipulate Speed pedal, you can control the speed, also known as Automatic Transmission Automatic Transmission (A T). It is According to the speed and load (throttle pedal travel) for two-parameter control, stall in accordance with the above two Parameters to automatically take-off and landing.A T and MT in common is that they are level transmission, but A T According to the speed of the speed shift automatically, you can eliminate the manual transmission "setback" of the shift feel. However, A T also have many drawbacks, such as body complex, mechanical efficiency is not high, high cost, reliability and control Sensitivity remains to be increasing . AMT (Automated Mechanical Transmission) is in the traditional dry clutch and manual transmission gear based on the transformation of form, mainly to change the part of the manual gearshift control. That is, the overall structure of the MT cases the same switch to electronically controlled automatic transmission to achieve. Semi-automatic control, there are two forms of transmission. A number of stalls is a common automatic control, and the remaining stalls manipulated by the driver; the other is pre-style, that is, pre-selected pilot stalls, the clutch pedal in the down or release the accelerator pedal, the for retirement or an electromagnetic device to shift the hydraulic device. In recent years, with advances in vehicle technology and road traffic density increased, the performance requirements of the transmission is also getting higher and higher. A large number of automotive engineers in improving the performance of automobile transmission study a great deal of effort devoted to the rapid transmission of technology development, such as A T, AMT, DCT, CVT and the emergence of IVT.2003 Hyundai A T, AMT, DCT, CVT forum reached a consensus on the following:in the next Development, MT will continue to be the most widely used automotive transmission, AMT will increase the proportion of the application, A T also Will occupy a large market share, CVT's use of certain limitations, can only be due to a number of small displacement Car, DCT (dual clutch transmission) will also be the budding growth. From 2003 to now, vehicle speed Thedevelopment of devices and the forum basically the consensus reached by consensus. By comparing the analysis, the traditional mechanical transmission is still the most widely used vehicle change Speed. Although it has many shortcomings, such as shifting the impact of large, bulky, cumbersome to manipulate and so on; however, it also There are many advantages, such as high transmission efficiency, reliable operation, long life, manufacturing processes mature and low cost. Therefore, if we can improve the mechanical transmission of the above-mentioned shortcomings, it still has great room for development.Second, Manual Transmission Fault DiagnosisManual transmission at the beginning of the fault diagnosis prior toFailure to confirm from other parts is not: to check the tire And wheels, to confirm the normal tire pressure, and the wheel is flat V alue of; to confirm instead of noise and vibration from the engine. Clutch , And steering and suspension, etc..(A), skip file1. PhenomenonV ehicle acceleration, deceleration, climbing or severe vehicle vibration, the gear lever neutral position automatically jump.2. Reasons① self-locking device of the ball did not enter the grooves or linked file does not meet the full-gear tooth meshing long;② self-locking device worn groove ball or serious, self-locking spring is too soft or broken fatigue;③ gear along the direction of tooth wear as a long cone-shaped;④ one or two too松旷shaft bearing, so that one or two three-axis and the crankshaft axis of the heart or different transmission and clutch shell shell bonding plane of the vertical axis the relative change in the crankshaft;⑤ Second Gear axis often axial or radial gap is too large;⑥ the axis of axial or radial gap is too large.3. Fault diagnosis and troubleshootingJump to file stalls Unascertained: After taking heat the entire vehicle, increase the use of continuous, slow approach to road test each file is determined.Will jump to the gear lever hanging file stalls the engine off, transmission cover removed carefully to observe the mating dance gear case file.① engagement does not meet the length, then the resulting fault;② to reach a total length of engagement, should continue to check;③ check mating wear parts: wear into a cone, then failure may be caused by;④ check b-axis of the gear profile and the axis of the axial and radial clearance, clearance is too large, then failure may be caused by;⑤ check self-locking devices, locking devices, if only a very small dynamic resistance, and even feel the ball is not plugged groove (the transmission cover caught in the vice, the hand-shaking shift stroke), the fault for the bad performance of self-locking ; Otherwise, the fault for the clutch and gearbox shell bonding plane and the vertical axis of the crankshaft caused by changes.(B), arbitrary files1. PhenomenonTechnical condition in the clutch normal circumstances, transmission at the same time put up or two files linked to the need to stall, the results linked to other stalls.2. Reasons① interlocking device failure: if the fork shaft, pin or interlocking interlocking ball too much wear and tear, etc.;② the bottom of the arc gear face wear and tear is too large or fork axis of the allocated blocks wear groove is too large;③ball pin gear lever broken or the ball-hole, ball松旷wear too. In short arbitrary file transmission is mainly due to institutional failure manipulation.3. Fault diagnosis and troubleshooting① linked to the need to stall, the results linked to the other stalls: rocking gear lever, to check their point of view before, if in excess of the normal range, while the lower end of failure by the gear lever ball pin and the positioning groove ball with or松旷, the ball is too large holes caused by wear and tear. Swung shift 360 °, compared with a broken pin.② If the pendulum angle to normal, still not on, or linked to more than picking file, then the lower end of failure by the gear lever away from the limitations arising from the groove in (due to break away from the bottom of the arc-shaped guide groove face wear and tear or wear).③ At the same time linked to the two files: the fault caused by the interlocking device failure.(C), the difficulties linked to files1. PhenomenonClutch technical condition, but can not be linked smoothly linked file into the stalls, often percussive sound gear.2. Reasons① synchronizer failure;② Bending fork shaft, locking the spring strong, ball injury, etc.;③ a shaft or a spline shaft bending injury;④ inadequate or excessive gear oil, gear oil does not meet the specifications.3. Fault diagnosis and troubleshooting①Synchronizer check whether the fall to pieces, cone ring is conical spiral groove wear, whether worn slider, spring is too soft, such as elastic.② If the Synchronizer normal, check whether the bending of a shaft, spline wear is severe.③ check whether the mobile axis normal fork.(D), abnormal sound transmission1. PhenomenonTransmission refers to transmission work abnormal sound when the sound is not normal.2. Reasons1) abnormal sound gearGear wear off very thin gap is too large, the impact of running in; bad tooth meshing, such as the repair did not replace the gear pairs. New and old gear with the gear mesh can not be correct; tooth metal fatigue spalling or damage to individual teeth broken; gear and the spline shaft with松旷, or the axial gear clearance is too large; axis caused by bending or bearing松旷space to change gears.2) Bearing ringSerious bearing wear; Bearing (outer) ring with the journal blocks (holes) with the loose; Ball Bearing Ma break-up or a point of ablation.3) ring made for other reasonsSuch as the transmission within缺油, lubricants have been thin, too thick or quality deterioration; transmission into the foreign body inside; some loose bolts fastening; odometer or the odometer shaft ring gear, such as fat.3. Troubleshooting①transmission issued metal dry friction sound, which is缺油and the poor quality of oil. Refueling and inspection should be the quality of oil, if necessary, replacement.② for moving into a file if the sound obvious, namely, the profile of gear tooth wear; If the occurrence of cyclical noise, while damage to individual teeth.③when the ring gap, and riding the clutch pedal under the noise disappeared after the general axis is a before and after the bearing or regular engagement ring gear; if any files are changed into the ring, after more than two-axis bearing ring.④transmission occurs when a sudden impact the work of sound, most of the tooth was broken and should be removed timely transmission inspection cover to prevent mechanicaldamage.⑤moving, only for transmission of a file into the ring gear made in the above-mentioned good premise, it should check with improper gear mesh, if necessary, should be re-assembling a pair of new gear. In addition, it may be synchronizer gear wear or damage should be repaired or replaced depending on the circumstances.⑥ when shifting gear ring made of impact, it may be the clutch or the clutch pedal can not be separated from stroke is incorrect, damaged synchronizer, excessive idling, gear improperly adjusted or tight-oriented, such as Bush. In such cases, to check whether the separation of the clutch, and then adjust the idle speed or the gear lever, respectively, the location, inspection-oriented with the bearing bushing and separation tightness.If excluded from the above examinations, the transmission is still made ring, should check the shaft bearings and shaft hole with the situation, bearing the state of their own technology, etc.; as well, and then view the odometer shaft and ring gear is made and, if necessary, be repaired or replacement.(E), transmission oil1. PhenomenonAround the transmission gear lubricants, transmission gear box to reduce the fuel can be judged as lubricant leakage.2. Reasons and troubleshooting① improper oil selection, resulting in excessive foam, or the volume too much oil, when in need of replacement or adjust the lubricant oil;② side cover is too loose, damaged gaskets, oil seal damage, damage to seals and oil seals should be replaced with new items;③ release and transmission oil tank and side cover fixed bolts loosening, tightening torque should be required;④ broken gear-housing shell or extended wear and tear caused by oil spills, must be replaced;⑤ odometer broken loose gear limit device must be locked or replaced; gear oil seal oil seal oil should be replaced.Third, the maintenance manual gearboxSantana is now as an example:Santana used to manually synchronize the entire, multi-stage gear transmission, there are four forward one block and reverse gear. Block are forward-lock synchronizer ring inertial, body-wide shift synchronizer nested engagement with a reasonable structure, the layout of a compact, reliable, long life and so on. However, if the use and maintenance is not the right way to do so, failure mayoccur at any time.The proper use of Synchronizer:1, the use of addition and subtraction block off both feet. Block addition and subtraction, if the clutch with one foot, then the speed at the time of addition and subtraction block must be correct, the timing should be appropriate and, if necessary, to addition and subtraction can be blocked off both feet, so that addition and subtraction method can reduce the block with Gear speed difference between the circumference, thereby reducing wear and tear Synchronizer to extend the life of Synchronizer.2, prohibited the use of tap-shift gear lever when the method (that is, a push of the operation of a song). Hand should always hold down the shift, this can greatly reduce the synchronizer sliding lock Moreton Central time and reduce wear and tear.3, no state in the gap off the use of force挂挡synchronizer start the engine. Moment of inertia as a great engine, the friction torque Synchronizer also small, so the time synchronization process is very long, so that lock ring temperature increased sharply, it is easy to burn synchronizer.4, is strictly prohibited by synchronizer clutch instead of the initial (that is, the use of non-use of the clutch friction synchronizer start挂挡role), control speed and braking.The correct use of lubricants:Santana at the factory, the transmission has been added to the quality of lubricating oil, under normal circumstances, the level of the transmission lubrication need to be checked. However, when normal travel 100,000 kilometers 10,000 kilometers -20 after the first lubricating oil must be replaced. Santana grade lubricants used in transmission as follows: Gear Oil API-GLA (MIL-L2105), SAE80 or SAE80W-90 grade汽车变速器一、汽车变速器概述及发展趋势汽车问世百余年来，特别是从汽车的大批量生产及汽车工业的大发展以来，汽车己为世界经济的发展、为人类进入现代生活，产生了无法估量的巨大影响，为人类社会的进步作出了不可磨灭的巨大贡献，掀起了一场划时代的革命。

中英文对照资料外文翻译文献Transmission SystemA Basic Parts of the transmission systemThe transmission system applies to the components needed to transfer the drive from the engine to the road wheels. The main components and their purposes are (1) Clutch --- to disengage the drive--- to provide a smooth take-up of the drive(2) Gearbox --- to increase the torque applied to the driving road wheels--- to enable the engine to operate within a given range of speed irrespective of the vehicle speed--- to give reverse motion of the vehicle--- to provide a neutral position so that the engine can run without moving the vehicle(3) Final drive --- to turn the drive through 90°--- to reduce the speed of the drive by a set amount to match the engine to the vehicle(4) Differential --- to allow the inner driving road wheel to rotate slower than the outerwheel when the vehicle is cornering, whilst it ensures that adrive is applied equally to both wheels.B Clutch and Clutch ServiceIn order to transmit the power of the engine to the road wheels of a car, a friction clutch and a change-speed gearbox are normally employed. The former is necessary in order to enable the drive to be taken up gradually and smoothly, while the latter provides different ratios of speed reduction from the engine to the wheels, to suit the particular conditions of running,A clutch performs two tasks:(1) it disengages the engine from the gearbox to allow for gear changing.(2) it is a means for gradually engaging the engine to the driving wheels, when a vehicle is to be moved from rest the clutch must engage a stationary gearbox shaft with the engine; this must be rotating at a high speed to provide sufficient power or else the load will be too great and the engine will start (come to test).C Clutch ActionTo start the engine, the driver must depress the clutch pedal. This disengages the gearbox from the engine. To move the car, the driver must reengage the gearbox to the engine. However, the engagement of the parts must be gradual. An engine at idle develops little power. If the two parts were connected too quickly, the engine would stall. The load must be applied gradually to operate the car smoothly.A driver depresses the clutch pedal to shift the gears inside the gearbox. After the driver releases the clutch pedal, the clutch must act as solid coupling device. It must transmit all engine power to the gearbox, without slipping.The clutch mechanism include three basic parts: driving member, driven member, operating members.●The driving memberThe driving member consists of two parts: the flywheel and the pressure plate. The flywheel is bolted directly to the engine crankshaft and rotates when the crankshaft turns. The pressure plate is bolted to the flywheel. The result is that both flywheel and pressure plate rotate together.●The driven memberThe driven member, or clutch disc, is located between the flywheel and pressure plate. The disc has a splined hub that locks to the splined input shaft on the gearbox .Any rotation of the clutch disc turns the input shaft .Likewise, any motion of the input shaft moves the clutch disc. The splines allow the clutch disc to move forward and backward on the shaft as it engages and disengages.The inner part of the clutch disc, called the hub flange, has a number of small coil springs. These springs are called torsional springs. They let the middle part of theclutch disc turn slightly on the hub. Thus, the springs absorb the torsional vibrations of the crankshaft. When the springs have compressed completely, the clutch moves back until the springs relax. In other words, the clutch absorbs these engine vibrations, preventing the vibrations from going through the drive train.●Operating MembersThese are the parts that release pressure from the clutch disc. The operating members consist of the clutch pedal, clutch return spring, clutch linkage, clutch fork, and throwout bearing. The clutch linkage includes the clutch pedal and a mechanical or hydraulic system to move the other operating members.When the clutch pedal is depressed, the clutch linkage operates the clutch fork .The clutch fork, or release fork, moves the throwout bearing against the pressure plate release levers. These levers then compress springs that normally hold the clutch disc tightly against the flywheel.At this point, the torque of the engine cannot turn the gearbox input shaft. The gears in the gearbox may be shifted or the vehicle can be brought to a full stop.When the clutch pedal is released, the pressure plate forces the clutch disc against the flywheel. The clutch return spring helps raise the pedal.D Clutch ServiceThe major parts of the clutch assembly need no maintenance or lubrication during normal service. However, all linkage parts need lubrication at points of contact. The linkage itself must be adjusted to prevent wear of the clutch disc.●Free-play AdjustmentYou can make only one adjustment on the clutch linkage —the free-play adjustment. Free play is the allowable space between the throwout bearing and the pressure plate release levers. This space is important because it prevents pressure on the levers that could keep the clutch from engaging fully. In other words, the throwout bearing must be slightly away from the pressure plate levers so that the bearing applies no pressure on the levers. On the other hand, there must not be too much freeplay between the bearing and the levers. With too much clearance, the clutch cannot fully disengaged when the driver press the clutch pedal to the floor. In most cases, you measure the free play at the clutch pedal, rather than at the bell housing.The free play allows some motion at the beginning of the clutch pedal travel, before the pedal meets resistance. Since the distance varies with the type of pressure plate, check the service manual. Usually, free play should be about 20 to 25mm.Free play can be adjusted at some point where the clutch linkage consists of threaded rods with locknuts. The rod closest to the clutch fork is the most common adjustment point. Begin by locating the rod and locknut beneath the vehicle. Then determine which way to turn the adjustment nuts to get the correct free play at the pedal. You can get a rough estimate of free play by moving the clutch fork to see if it still has some movement. The best way to make the adjustment is to loosen the locknut and move the adjustment nut a few turns. Then check the free play at the pedal. Continue making adjustments until you have the correct free play. When the free-play adjustment meets the manufacturer’s specification, tighten the locknut.Check the free-play adjustment every six months and make any adjustment. Clutches need adjustment that often, since free play decreases slightly as the clutch disc wears. However, the need for frequent adjustments means a problem in the clutch mechanism itself.There must be free play between the throwout bearing and pressure plate release levers. Problems can result from “riding the clutch”. A driver who rests one foot on the clutch pedal causes the throwout bearing to rub against the clutch release levers. As a result, the throwout bearing becomes worn quickly. Also, the clutch disc may wear out due to slippage because the parts are not fully engaged.●Clutch FaultsThe following are the main faults:Slip —failure of the surface to grip resulting in the driven plate revolving slower than the engine flywheel : Clutch gets hot and emits an odor.Spin or drag —failure of the plates to separate resulting in noise from thegearbox when selecting a gear: most noticeable when thevehicle is stationary.Judder —a vibration which occurs when the clutch is being engaged , i.e. when the vehicle is stationary.Fierceness —sudden departure of the vehicle even though the pedal is being released gradually.E The Clutches（supplementary contract）A clutch is a friction device used to connect and disconnect a driving force from a driven member. In automotive applications, it is used in conjunction with an engine flywheel to provide smooth engagement and disengagement of the engine and manual transmission.Since an internal combustion engine develops little power or torque at low rpm, it must gain speed before it will move the vehicle. However, if a rapidly rotating engine is suddenly connected to the drive line of a stationary vehicle, a violent shock will result.So gradual application of load, along with some slowing of engine speed , is needed to provide reasonable and comfortable starts. In vehicles equipped with a manual transmission, this is accomplished by means of a mechanical clutch.The clutch utilizes friction for its operation. The main parts of the clutch are a pressure plate, and a driven disk. The pressure plate is coupled with the flywheel, while the driven disk is fitted to the disk by the springs so that the torque is transmitted owing to friction forces from the engine to the input shaft of the transmission. Smooth engagement is ensured by slipping of the disk before a full pressure is applied.The automobiles are equipped with a dry spring-loaded clutch. The clutch is termed “dry”because the surfaces of the pressure plate and driven disks are dry in contrast to oil-bath clutches in which the plate and disks operate in a bath of oil. It is called “springloaded”because the pressure plate and the driven disk are always pressed to each other by springs and are released only for a time to shift gears or to brake the automobile.In addition to the plate and disk, the clutch includes a cover, release levers, a release yoke, pressure springs and a control linkage. The clutch cover is a steel stamping bolted to the flywheel. The release levers are secured inside the cover on the supporting bolts. The outer ends of the release levers are articulated to the pressure plate. Such a construction allows the pressure plate to approach the cover or move away from it, all the time rotating with the cover or move away from it, all the time rotating with the flywheel. The springs spaced around the circumference between the pressure plate and the clutch cover clamp the driven disk between the pressure plate and the flywheel.The springs are installed with the aid of projections and sockets provided on the cover and pressure plate. The pressure plate sockets have thermal-insulation gaskets for protecting the springs against overheating.The clutch release mechanism can be operated either mechanically or hydraulically. The mechanically-operated release mechanism consists of a pedal, a return spring, a shaft with lever, a rod m release yoke lever, a release yoke, a release ball bearing with support and a clutch release spring. When the clutch pedal is depressed, the rod and shaft with yoke shift the release bearing and support assembly. The release bearing presses the inner ends of the release levers, the pressure plate is moved away from the driven disk and the clutch is disengaged. To engage the clutch , the pedal is released, the release bearing and support assembly is shifted back by the return spring thus releasing the release levers so that the pressure plate is forced by its springs towards the flywheel to clamp the driven disk and engage the clutch.The clutch hydraulically-operated release mechanism consists of a clutch pedal , clutch release spring , a main cylinder , a pneumatic booster, pipelines and hoses and a lever of the clutch release yoke shaft. Time main cylinder accommodates a piston with a cup. The pneumatic booster serves to decrease the pedal force required disengage the clutch. The booster includes two housings with the servo diaphragm clamped in between. The housing accommodates pneumatic, hydraulic and servo plungers. When the clutch pedal is pushed, the fluid pressure from the main cylinder is transmitted through the pipelines and hoses to the hydraulic and servo plungers of the pneumaticbooster.The servo arrangement is intended for automatic change of the air pressure in the pneumatic cylinder proportionally to the force applied to the pedal. The plunger moves with the diaphragm, the outlet valve closes and the inlet valve opens thus admitting the compressed air to the pneumatic plunger piston. The forces created by the pneumatic and hydraulic plungers are added together and are applied through the push rod to the release yoke shaft lever; the lever turns the shaft and the release yoke, thus disengaging the clutch. After the clutch pedal is released, the outlet valve opens and the air from the cylinder is let out to the atmosphere.Automatic clutches were used in certain U.S. and European cars. American Motors’“E-Stick”clutch eliminated the need for physical operation of the clutch system called “Hydrak”, which consisted of a fluid flywheel connected to a single, dry disk clutch.In the “E-Stick” set up, the pressure plate levers “engage” the clutch disk rather than “release” them. Also, the clutch remains disengaged until a servo unit is applied by oil pressure when the shift lever is placed “in gear” with the engine running.The “Hydrak”unit also begins operation when the lever is “in gear”. This activates a booster unit, which disengages the clutch disk. The hydraulic clutch parts are bridged over by a free-wheel unit, which goes into action when the speed of the rear wheel is higher than the speed of the engine. A special device controls engagement of the mechanical clutch, depending on whether the rear axle is in traction or is pushed by car momentum.A more-or-les unusual clutch pressure plate set-up is used on late model Chrysler and American Motors cars. Called a semi-centrifugal clutch, the pressure plate has six cylindrical rollers which move outward under centrifugal force until they contact the cover. As engine speed increases, the rollers wedge themselves between the pressure plate and cover so that the faster the clutch rotates, the greater the pressure exerted on the pressure plate and disk.传动系统A基本传动系统的组成部份传动系统是将发动机动力转移到驱动轮的结构。

汽车离合器中英文对照外文翻译文献(文档含英文原文和中文翻译)Fethermal analysis of a ceramic clutch1. IntroductionAbrasive dry running vehicle clutches are force closure couplings. Torque and speed transmission are ensured by the frictional force generated between two pressed surfaces. Reasons for the application of ceramic as a friction medium include good heat and wear resistance properties, which provide the opportunity to drive higher pressures, and a low density. Thus, an increasing power density is enabled with a parallel minimization of construction space.Measurements with a first prototype of a clutch disk using ceramic facings were performed at Karlsruhe University in a laboratory specialized in passenger car drive system testing. In the course of analysis the finite element (FE) model was to be constructed with the knowledge of measurement data and measurement conditions. Calculations were intended to determine the temperature distribution of the clutch disk and its environment at each moment in time corresponding to measurements. It is essential to be familiar with the temperature range in order to examine the wear characteristics of the system. Thus,important information is derived from measurement data. In critical load cases, the highest expected temperatures must be forecast in space and time in order to protect measuring instruments close to the location of heat generation.The goal of this study is to analyze and modify the clutch system to provide better operating conditions by improving the heat conduction and convection of the system or to increase the amount of the energy converted into frictional heat. Furthermore, it is desired to find better design solutions for more efficient clutch systems.Calculations were performed by the Cosmos Design Star software. During model development, great care had to be taken for proper simplification of geometry, the selection of element sizes, and the correct adjustment of time steps due to the substantial hardware requirements for transient calculations. Changes in thermal parameters such as the surface heat convection coefficient and thermal load had to be taken into consideration on an on-going basis in terms of time and location. The two sides of the analyzed test clutch system can only be managed by two independent models linked by heat partition, according to the hypothesis that the contact temperature must be identical on both sides while there is proper contact between them and its value must be adjusted by iteration. Calculations revealed that the heat partition changed by cycle and it differed along the inner and outer contact rings. As a result of the different cooling characteristics between the ceramic and steel side, a heat flow is launched from the ceramic side to the steel side. This heat flow was also determined by iteration, its value also changes by cycle and differs along the inner and outer contact rings.2. First prototype of a clutch using engineering ceramics as friction materialThe examined clutch disk was developed according to the “specific ceramic” product development process established at the Institute for Product Development (IPEK) at the University of Karlsruhe. This development process already has the possibility for connection to a real transmission shaft; further, it has a cushion spring device for the facings allowing good start behaviour. Abrasive clutches must comply with the following basic requirements:●high torque transmission according to high friction coefficients,●high comfort (no vibrations through self-induced chattering),●homogeneous temperature distribution,●low wear characteristic.A critical element of the switch is the abrasive disk.With regard to the design utmost care must be taken to select the right material. A high and constant friction coefficient,，wear resistance and thermal resistance are desired characteristics. The clutch disk has instead of the generally applied ring-shaped abrasive inlet two rows of SSIC (as sintered) ceramic pellets. These pellets are placed on 6 separate segments. The segments are fixed to the central hub by rivets. Each segment consists of 4 plates, 2 working as facing springs and 2 as carriers.3. MeasurementsMeasurements were performed at the department of power train development of the Institute for Product Development (IPEK) at the Karlsruhe University (TH) Research University, where a category IV component test rig is used for tests of new frictional materials and examinations of new materials in real clutch disks. Real conditions are applied by the simulation of driving resistance (e.g. starting in the plane, starting at the hill). It is a component test rig leveled on the fourth position of the tribological testing environment.In order to give an idea of dimensions: the equipment length is about 4-5m. The two electric motors and the axial force are controlled independently by computer; thereby many operational states can be realized. This enables the equipment to complete a myriad of tribological measurements all while properly modeling the operation of a clutch disk in a passenger car. It is also equipped with an automatic IT measurement system. Measurable quantities include the following:●two heavy-duty electric motors (150 KW, Baumuller DS 160L-305),●device suitable for exerting axial force,●torque meter (Manner Sensortelemetrie MF100),●axial force meter,●steel disk in friction,●replaceable head to affix the device to be tested,●temperature along two different radii at 0.4mm below the abrasive surface of the steeldisk (Omega HJMTSS-IM100U-150-2000,J-typeiro-constantan thermocouples),●revolutions per minute for both sides (Polytene LSV 065).The greatest challenge out of these is temperature measurement as we would like to know the temperature of the revolving steel disk. The two thermoelements placed in the steel disk forward data to the computer through a wireless blue tooth system and are placed 0.4mm below the abrasive surface of the steel disk on the two opposite arcs of the clutch disk.3.2. Measurement processDue to component analyses and cost reduction only one side of the clutch disk is mounted with ceramic facings. Thus, the clutch disk and its fitting will be referred to as the ceramic side, and the abrasive steel disk with its environment revolving together will be referred to as the steel side. In the course of measurements, data were collected at a sampling frequency of 100 and 1000HZ. Measurements were conducted according to the time curves.The measurement starts by increasing the revolutions per minute of the steel side (the driving side) to a specific value (1500 rpm here). Then the ceramic side (the driven side), held at zero rpm, is pushed towards the steel disk and the axial force is applied until a designated value is reached (nominally 4200N here). Upon reaching the designated axial force the ceramic side is released and the two sides start to synchronize. A few seconds after synchronization, the axial load is discontinued and after some time both the steel and the ceramic sides—revolving at the same speed—are slowed down. This is deemed to be one measurement cycle. Ten cycles are completed in the course of a single measurement. During application of the axial force the ceramic side is held at zero rpm until the desired force is reached to ensure synchronization occurs at nearly the same time of each cycle. This is unfavorable from the viewpoint of both measurements and calculations. Measurements are usually conducted by changing only 3 parameters: the speed, the axial load and the inertia. The following figures are applied in various combinations:●speed n: 700, 1100 and 1500 (rpm),●axial force F: 4200, 6400 and 8400 (N) andinertia I: 1, 1.25 and 1.5 (kgm2).Experimental measurements are launched with approx.10-15 min intervals, during which the system cools down to about 30-40 1C. This makes calculations difficult, as the exact temperature distribution of the system is not known at the commencement of the measurement. However, it can be assumed that a period of 10-15min is sufficient for a nearly homogeneous temperature distribution to be produced. The parameters for the following simulation have been chosen for an intermediate case with a speed n =1500 rpm, an axial force F = 4200 N and an inertia I = 1 kg m2.4. Calculations of heat generationThe mechanical energy consumed during the friction of two bodies is transformed into heat. The generated heat can be calculated by the following simple formula: Q =μ·ν·F [W] .where m is the the frictional coefficient; v is the sliding velocity; F is the force perpendicularly compressing the surfaces. And the heat flux density per surface unit is q=μ·ν·p [Wm2].where p is the the pressure calculated as a ratio of the force and the contacting surface. As the ceramic tablets are placed at two different radii along the clutch disk, the heat generated must be calculated separately for each radii. Sliding can be divided into two sections. In the first section, the ceramic side is kept in a stationary position by braking, meanwhile the axial load is increased; therefore compression changes in the course of time while the speed difference between the two sides is constant. In the second section (at synchronization) the speed difference is equalized while the force value is constant, so velocity changes in time. On the basis thereof, the heat generated is.The nominal contact area is the aggregate of the contacting surfaces of the 24 and 18 ceramic tablets on the given ring. The diameter of ceramic tablets is:.Calculations were performed for the load case to be characterized by the following parameters:.Based on experimental measurements a constant friction coefficient of 0.4 was established..The velocity can be calculated with the knowledge of the radius and the speed..Surface pressure can be calculated as a ratio of the axial force and the contacting surface. This produces the same figure for each ceramic pellet, assuming an even load distribution..Thus, the maximum values of the generated heat are.In the first section of sliding, the generated heat is rising due to the increase of the load force; in the second section, it is decreasing due to the equalization of the speed difference. It is necessary to know the time of each sliding section in order to be able to specify the generated heat time curve. These can be determined from measurement dataseries. Synchronization time can be easily determined from the speed of the ceramic side. Speed increase is linear. Force increase is non-linear. For the sake of simplicity, force increase was substituted by a straight line in calculations so that the area below the straight line is nearly identical with the area measured below the curve. Thus, the time difference between the two terminal points of the straight line is the time of the first sliding section.The above-mentioned method was applied for each cycle and their average was specified. Based on these results, the following values were determined for sliding times:.Now the time curve of heat generation can be produced. The same curve was used in each cycle as there were no significant differences between parameters in each cycle. The generated heat-calculated this way-will appear as thermal load in the thermal model. It must be distributed appropriately between the contacting surfaces by taking into consideration heat partition. Heat partition requires the contact temperatures to be identical at both surfaces. Correct adjustment requires repeated iterations.有限元热分析的陶瓷离合器1 引言磨料空转车辆离合器是力封闭联轴器。

中英文对照外文翻译文献(文档含英文原文和中文翻译)How Automatic Transmissions WorkIf you have ever driven a car with an automatic transmission, then you know that there are two big differences between an automatic transmission and a manual transmission:There is no clutch pedal in an automatic transmission car.There is no gear shift in an automatic transmission car. Once you put the transmission into drive, everything else is automatic.Both the automatic transmission (plus its torque converter) and a manual transmission (with its clutch) accomplish exactly the same thing, but they do it in totally different ways. It turns out that the way an automatic transmission does it is absolutely amazing!In this article, we'll work our way through an automatic transmission. We'll start with the key to the whole system: planetary gear sets. Thenwe'll see how the transmission is put together, learn how the controls work and discuss some of the intricacies involved in controlling a transmission.Some BasicsJust like that of a manual transmission, the automatic transmission's primary job is to allow the engine to operate in its narrow range of speeds while providing a wide range of output speeds.Without a transmission, cars would be limited to one gear ratio, and that ratio would have to be selected to allow the car to travel at the desired top speed. If you wanted a top speed of 80 mph, then the gear ratio would be similar to third gear in most manual transmission cars.You've probably never tried driving a manual transmission car using only third gear. If you did, you'd quickly find out that you had almost no acceleration when starting out, and at high speeds, the engine would be screaming along near the red-line. A car like this would wear out very quickly and would be nearly undrive able.So the transmission uses gears to make more effective use of the engine's torque, and to keep the engine operating at an appropriate speed.The key difference between a manual and an automatic transmission is that the manual transmission locks and unlocks different sets of gears to the output shaft to achieve the various gear ratios, while in an automatic transmission, the same set of gears produces all of the different gear ratios. The planetary gear set is the device that makes this possible in an automatic transmission.GearsThis automatic transmission uses a set of gears, called a compound planetary gear set, that looks like a single planetary gear set butactually behaves like two planetary gear sets combined. It has one ring gear that is always the output of the transmission, but it has two sun gears and two sets of planets.Let's look at some of the parts:First GearIn first gear, the smaller sun gear is driven clockwise by the turbine in the torque converter. The planet carrier tries to spin counterclockwise,but is held still by the one-way clutch (which only allows rotation in the clockwise direction) and the ring gear turns the output. The small gear has 30 teeth and the ring gear has 72, so the gear ratio is:Ratio = -R/S = - 72/30 = -2.4:1So the rotation is negative 2.4:1, which means that the output direction would be opposite the input direction. But the output direction is reallythe same as the input direction -- this is where the trick with the twosets of planets comes in. The first set of planets engages the second set, and the second set turns the ring gear; this combination reverses the direction. You can see that this would also cause the bigger sun gear to spin; but because that clutch is released, the bigger sun gear is free to spin in the opposite direction of the turbineSecond GearThis transmission does something really neat in order to get the ratio needed for second gear. It acts like two planetary gear sets connected to each other with a common planet carrier.The first stage of the planet carrier actually uses the larger sun gearas the ring gear. So the first stage consists of the sun (the smaller sun gear), the planet carrier, and the ring (the larger sun gear).The input is the small sun gear; the ring gear (large sun gear) is held stationary by the band, and the output is the planet carrier. so theformula is:1 + R/S = 1 + 36/30 = 2.2:1The planet carrier turns 2.2 times for each rotation of the small sun gear. At the second stage, the planet carrier acts as the input for the second planetary gear set, the larger sun gear (which is held stationary) acts as the sun, and the ring gear acts as the output, so the gear ratio is:1 / (1 + S/R) = 1 / (1 + 36/72) = 0.67:1To get the overall reduction for second gear, we multiply the first stage by the second, 2.2 x 0.67, to get a 1.47:1 reduction. This may sound wacky, but it works.Third GearMost automatic transmissions have a 1:1 ratio in third gear. You'll remember from the previous section that all we have to do to get a 1:1output is lock together any two of the three parts of the planetary gear. With the arrangement in this gear set it is even easier -- all we have todo is engage the clutches that lock each of the sun gears to the turbine.If both sun gears turn in the same direction, the planet gears lockup because they can only spin in opposite directions. This locks the ring gear to the planets and causes everything to spin as a unit, producing a 1:1 ratio. OverdriveBy definition, an overdrive has a faster output speed than input speed.It's a speed increase. In this transmission, engaging the overdrive accomplishes two things at once. If you read How Torque Converters Work,you learned about lockup torque converters. In order to improve efficiency, some cars have a mechanism that locks up the torque converter so that the output of the engine goes straight to the transmission.In this transmission, when overdrive is engaged, a shaft that is attached to the housing of the torque converter (which is bolted to the flywheel of the engine) is connected by clutch to the planet carrier. The small sungear freewheels, and the larger sun gear is held by the overdrive band. Nothing is connected to the turbine; the only input comes from theconverter housing. Let's go back to our chart again, this time with the planet carrier for input, the sun gear fixed and the ring gear for output.Ratio = 1 / (1 + S/R) = 1 / ( 1 + 36/72) = 0.67:1So the output spins once for every two-thirds of a rotation of the engine. If the engine is turning at 2000 rotations per minute (RPM), the outputspeed is 3000 RPM. This allows cars to drive at freeway speed while the engine speed stays nice and slow.ReverseReverse is very similar to first gear, except that instead of the small sun gear being driven by the torque converter turbine, the bigger sun gear is driven, and the small one freewheels in the opposite direction. The planet carrier is held by the reverse band to the housing. So, according to our equations from the last page, we have:Ratio = -R/S = 72/36 = 2.0:1So the ratio in reverse is a little less than first gear in this transmission. Gear RatiosThis transmission has four forward gears and one reverse gear. Let's summarize the gear ratios, inputs and outputs:Gear Input Output FixedGear Ratio1st 30-tooth sun72-toothringPlanetcarrier2.4:12nd30-tooth sunPlanetcarrier36-toothring2.2:1Planetcarrier72-toothring36-toothsun0.67:1Total 2nd 1.47:13rd30- and 36-tooth suns72-toothring1.0:1OD Planet 72-tooth 36-tooth 0.67:1carrier ring sunRever se 36-tooth sun72-toothringPlanetcarrier-2.0:1Hydraulic SystemThe automatic transmission in your car has to do numerous tasks. You may not realize how many different ways it operates. For instance, here are some of the features of an automatic transmission:If the car is in overdrive (on a four-speed transmission), the transmission will automatically select the gear based on vehicle speed and throttle pedal position.If you accelerate gently, shifts will occur at lower speeds than if you accelerate at full throttle.If you floor the gas pedal, the transmission will downshift to the next lower gear.If you move the shift selector to a lower gear, the transmission will downshift unless the car is going too fast for that gear. If the car is going too fast, it will wait until the car slows down and then downshift.If you put the transmission in second gear, it will never downshift or up shift out of second, even from a complete stop, unless you move the shift lever.You've probably seen something that looks like this before. It isreally the brain of the automatic transmission, managing all of these functions and more. The passageways you can see route fluid to all the different components in the transmission. Passageways molded into the metal are an efficient way to route fluid; without them, many hoses would be needed to connect the various parts of the transmission. First, we'll discuss the key components of the hydraulic system; then we'll see how they work together.The PumpAutomatic transmissions have a neat pump, called a gear pump. The pump is usually located in the cover of the transmission. It draws fluid from a sump in the bottom of the transmission and feeds it to the hydraulic system. It also feeds the transmission cooler and the torque converter.The inner gear of the pump hooks up to the housing of the torque converter, so it spins at the same speed as the engine. The outer gear is turned by the inner gear, and as the gears rotate, fluid is drawn up fromthe sump on one side of the crescent and forced out into the hydraulic system on the other side.The GovernorThe governor is a clever valve that tells the transmission how fast thecar is going. It is connected to the output, so the faster the car moves,the faster the governor spins. Inside the governor is a spring-loaded valve that opens in proportion to how fast the governor is spinning -- the faster the governor spins, the more the valve opens. Fluid from the pump is fed to the governor through the output shaft.The faster the car goes, the more the governor valve opens and the higher the pressure of the fluid it lets through.Valves and ModulatorsThrottle Valve or ModulatorTo shift properly, the automatic transmission has to know how hard the engine is working. There are two different ways that this is done. Somecars have a simple cable linkage connected to a throttle valve in the transmission. The further the gas pedal is pressed, the more pressure isput on the throttle valve. Other cars use a vacuum modulator to apply pressure to the throttle valve. The modulator senses the manifold pressure, which drops when the engine is under a greater load.Manual ValveThe manual valve is what the shift lever hooks up to. Depending on which gear is selected, the manual valve feeds hydraulic circuits that inhibitcertain gears. For instance, if the shift lever is in third gear, it feedsa circuit that prevents overdrive from engaging.Shift ValvesShift valves supply hydraulic pressure to the clutches and bands to engage each gear. The valve body of the transmission contains several shift valves. The shift valve determines when to shift from one gear to the next. For instance, the 1 to 2 shift valve determines when to shift from first to second gear. The shift valve is pressurized with fluid from the governor on one side, and the throttle valve on the other. They are supplied with fluid by the pump, and they route that fluid to one of two circuits to control which gear the car runs in.The shift valve will delay a shift if the car is accelerating quickly. If the car accelerates gently, the shift will occur at a lower speed. Let's discuss what happens when the car accelerates gently.As car speed increases, the pressure from the governor builds. Thisforces the shift valve over until the first gear circuit is closed, and the second gear circuit opens. Since the car is accelerating at light throttle, the throttle valve does not apply much pressure against the shift valve.When the car accelerates quickly, the throttle valve applies morepressure against the shift valve. This means that the pressure from the governor has to be higher (and therefore the vehicle speed has to be faster) before the shift valve moves over far enough to engage second gear.Each shift valve responds to a particular pressure range; so when the car is going faster, the 2-to-3 shift valve will take over, because thepressure from the governor is high enough to trigger that valve.Electronic ControlsElectronically controlled transmissions, which appear on some newer cars, still use hydraulics to actuate the clutches and bands, but each hydraulic circuit is controlled by an electric solenoid. This simplifies the plumbing on the transmission and allows for more advanced control schemes.自动变速器如何工作如果你曾经驾驶过一辆带着自动变速器的车, 那么你就知道自动变速器和手动变速器之间有很大的不同:在一个带着自动变速器的汽车中没有离合器踏板。

减速器论文中英文对照资料外文翻译文献What is a Gearbox?A XXX.1.The n of a Gearbox1) The gearbox ces the speed while increasing the output torque。

The torque output。

is the motor output multiplied by the n。

but it should not exceed the XXX.2) The gearbox also ces the inertia of the load。

which decreases by the square of the n。

Most motors have an inertia value that can be XXX.2.Types of GearboxesCommon gearboxes include bevel gear cers (including parallel-axis bevel gear cers。

worm gear cers。

and cone gear cers)。

ary gear cers。

cycloid cers。

worm gear cers。

XXX.mon Gearboxes1) The main feature of the worm gear cer is its reverse self-locking n。

which can achieve a large n。

The input and output shafts are not on the same axis or in the same plane。

However。

it generally has a large volume。

low n efficiency。

and low n.2) XXX and power。

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自动变速器现代自动变速箱是当今汽车迄今为止,最复杂的机械组件.自动变速器包含机械系统、液压系统、电气系统和计算机控制.它们几乎无声地完美和谐的工作在一起,直到出现问题. 这篇文章将帮助您了解这些技术奇迹背念，让你进入当它们工作出在问题如何修复的天地.这篇文章分为四个部分:∙什么是变速器损坏在最简单的条件下，变速器的用途是什么.∙在他们变得更坏前发现问题，展示如何寻找并防止小问题变成大问题.∙维修谈大家也应该知道的预防性维修.∙变速器修理描述典型地执行在变速器从较小调整完成检修的修理形式。

什么是变速器?变速器是一个连接到背面发动机,并将动力从发动机传到驱动车轮的装置. 汽车发动机工作在它最佳的一些转速(转每分钟) 范围内，而变速器的工作就是在发动机转速在一定范围内确保动力被分到各个轮子.这个通过各种齿轮组合来实现的. 在一档里, 发动机快速转动传到驱动轮，而在高挡时发动机空转，即使汽车可能行驶超出70 里/时。

除各种各样的前进齿轮之外,变速器也有一个并没有连接从驱动轮到发动机的中性位置, 并且相反,能使驱动轮相反转动允许你倒退。

最后，是停车位置。

在这个位置, 门闩机制(不似一个非螺栓锁住门) 被插入入一个槽孔在输出轴去锁住驱动轮和保持它们转动, 从而防止车辆滚动.。

有两个基本类型的汽车自动变速器基于是否后轮驱动或前轮驱动.对后轮驱动汽车，变速器通常安装到后面的发动机和位于地板的中心沿着油门踏板位置.一根传动轴连接变速器后方到位于后车轴被用来传递动力到后轮的主减速器. 动力流在这个系统是从引擎简单和直接向前传递, 通过扭矩交换器,然后通过变速器和传动轴直到到达主减速器，分散开传到两个后轮.对前轮驱动汽车，变速器通常由一根传动轴与主减速器结合起来.发动机在前轮驱动车上通常安装在汽车上的侧身和传动轴下面发动机的一侧面面向汽车后方.前轴直接与传动轴相连，提供动力给前轮.这个例子,动力从发动机，通过变矩器传递到一个大链子能够传递动力通过转180度到发动机侧面的变速器.从那里,动力路线通过变速器到主减速器，通过驱动轴分散开传到两个前轮.还有一些其他的布置包括前面驱动发动机安装由前至后代替侧方,还有其他所有四轮驱动但这里所说的两个系统是目前最常用的.较为冷门后轮驱动，发动机在后方直接安装到主减速器通过一个驱动轴连接到还安放在发动机的变矩器. 这个系统被发现在护卫舰和被使用是为了平衡前轮和后轮的重量去改进性能和处理.另一个后轮驱动系统安装一切，发动机，变速器和主减速器在后方.发现问题在它们变得更坏之前∙在汽车下寻找泄漏或污点如果有一个红色持续漏油那一定是来自你的车,你应该去车店看看它是否来自你的变速器或可能从动力转向系统(大部分动力转向系统还利用变速器液及泄漏可能大致出现在地面同一区域和变速器泄漏一样。

外文原文版出处： Publisher - IJEDR (ISSN - 2321-9939)Pubished in - Volume 5 | Issue 2 | April 2017Unique Identification Number - IJEDR1702134International Journal of Engineering Development and Research译文成绩：指导教师（导师组长）签名：译文：摘要--本项目以其设计和工作原理，了解齿轮传动系统原理。

汽车使用不同的齿轮。

齿轮有啮齿来传送驱动器。

根据理论计算，对齿轮箱组件进行了有限元分析，并对减速机的设计进行了简要的研究。

关键词：变速箱设计，变速箱开发1.1介绍变速器是电力传输系统中的一种机器，它提供了控制功率的应用。

通常术语传输仅仅指使用齿轮和齿轮列车提供转速和扭矩转换从一个旋转电源到另一个设备的齿轮箱。

我们知道，汽车发动机在一定的转速下能够达到最好的状态，此时发出的功率比较大，燃油经济性也比较好。

因此，我们希望发动机总是在最好的状态下工作。

但是，汽车在使用的时候需要有不同的速度，这样就产生了矛盾。

这个矛盾要通过变速器来解决。

汽车变速器的作用用一句话概括，就叫做变速变扭，即增速减扭或减速增扭。

为什么减速可以增扭，而增速又要减扭呢？设发动机输出的功率不变，功率可以表示为 N = wT，其中 w 是转动的角速度，T 是扭距。

当 N 固定的时候，w 与 T 是成反比的。

所以增速必减扭，减速必增扭。

汽车变速器齿轮传动就根据变速变扭的原理，分成各个档位对应不同的传动比，以适应不同的运行状况。

一般的手动变速器内设置输入轴、中间轴和输出轴，又称三轴式，另外还有倒档轴。

三轴式是变速器的主体结构，输入轴的转速也就是发动机的转速，输出轴转速则是中间轴与输出轴之间不同齿轮啮合所产生的转速。

不同的齿轮啮合就有不同的传动比，也就有了不同的转速。

AUTOMOTIWE FINAL DRIVEFINAL DRIVEA final drive is that part of a power transmission system between the drive shaft and the differential. Its function is to change the direction of the power transmitted by the drive shaft through 90 degrees to the driving axles. At the same time. it provides a fixed reduction between the speed of the drive shaft and the axle driving the wheels.The reduction or gear ratio of the final drive is determined by dividing the number of teeth on the ring gear by the number of teeth on the pinion gear. In passenger vehicles, this speed reduction varies from about 3:1 to 5:1. In trucks it varies from about 5:1 to 11:1. To calculate rear axle ratio, count the number of teeth on each gear. Then divide the number of pinion teeth into the number of ring gear teeth. For example, if the pinion gear has 10 teeth and the ring gear has 30 (30 divided by 10), the rear axle ratio would be 3:1. Manufacturers install a rear axle ratio that provides a compromise between performance and economy. The average passenger car ratio is 3.50:1.The higher axle ratio, 4.11:1 for instance, would increase acceleration and pulling power but would decrease fuel economy. The engine would have to run at a higher rpm to maintain an equal cruising speed.The lower axle ratio. 3:1, would reduce acceleration and pulling power but would increase fuel mileage. The engine would run at a lower rpm while maintaining the same speed.The major components of the final driveinclude the pinion gear, connected to the drive shaft, and a bevel gear or ring gear that is bolted or riveted to the differential carrier. To maintain accurate and proper alignment and tooth contact, the ring gear and differential assembly are mounted in bearings. The bevel drive pinion is supported by two tapered roller bearings, mounted in the differential carrier. This pinion shaft is straddle mounted. meaning that a bearing is located on each side of the pinion shaft teeth. Oil seals prevent the loss of lubricant from the housing where the pinion shaft and axle shafts protrude. As a mechanic, you willencounter the final drive gears in the spiral bevel and hypoid design.Spiral Bevel GearSpiral bevel gears have curved gear teeth with the pinion and ring gear on the same center line. This type of final drive is used extensively in truck and occasionally in older automobiles. This design allows for constant contact between the ring gear and pinion. It also necessitates the use of heavy grade lubricants.Hypoid GearThe hypoid gear final drive is an improvement or variation of the spiral bevel design and is commonly used in light and medium trucks and all domestic rear- wheel drive automobiles. Hypoid gears have replaced spiral bevel gears because they lower the hump in the floor of the vehicle and improve gear-meshing action. As you can see in figure 5-13, the pinion meshes with the ring gear below the center line and is at a slight angle (less than 90 degrees).Figure 5-13.—Types of final drives.This angle and the use of heavier (larger) teeth permit an increased amount of power to be transmitted while the size of the ring gear and housing remain constant. The tooth design is similar to the spiral bevel but includes some of thecharacteristics of the worm gear. This permits the reduced drive angle. The hypoid gear teeth have a more pronounced curve and steeper angle, resulting in larger tooth areas and more teeth to be in contact at the same time. With more than one gear tooth in contact, a hypoid design increases gear life and reduces gear noise. The wiping action of the teeth causes heavy tooth pressure that requires the use of heavy grade lubricants.Double-Reduction Final DriveIn the final drives shown in figure 5-13, there is a single fixed gear reduction. This is the only gear reduction in most automobiles and light- and some medium-duty trucks between the drive shaft and the wheels.Double-reduction final drives are used for heavy- duty trucks. With this arrangement (fig. 5-14) it is not necessary to have a large ring gear to get the necessary gear reduction. The first gear reduction is obtained through a pinion and ring gear as the single fixed gear reduction final drive. Referring to figure 5-14, notice that the secondary pinion is mounted on the primary ring gear shaft. The second gear reduction is the result of the secondary pinion which is rigidly attached to the primary ring gear, driving a large helical gear which is attached to the differential case. Double-reduction final drives may be found on military design vehicles, such as the 5-ton truck. Many commercially designed vehicles of this size use a single- or double-reduction final drive with provisions for two speeds to be incorporatedFigure 5-14.—Double-reduction final driveTwo-Speed Final DriveThe two-speed or dual-ratio final drive is used to supplement the gearing of the other drive train components and is used in vehicles with a single drive axle (fig. 5-15). The operator can select the range or speed of this axle with a button on the shifting lever of the transmission or by a lever through linkageThe two-speed final drive doubles the number of gear ratios available for driving the vehicle under various load and road conditions. For example, a vehicle with a two-speed unit and a five-speed transmission, ten different forward speeds are available. This unit provides a gear ratio high enough to permit pulling a heavy load up steep grades and a low ratio to permit the vehicle to run at high speeds with a light load or no loadThe conventional spiral bevel pinion and ring gear drives the two-speed unit, but aplanetary gear train is placed between the differential drive ring gear and the differential case. The internal gear of the planetary gear train is bolted rigidly to the bevel drive gear. A ring on which the planetary gears are pivoted is bolted to the differential case. A member, consisting of the sun gear and a dog clutch, slides on one of the axle shafts and is controlled through a button or lever accessible to the operatorWhen in high range, the sun gear meshes with the internal teeth on the ring carrying the planetary gears and disengages the dog clutch from the left bearing adjusting ring, which is rigidly held in the differential carrier. In this position, the planetary gear train is locked together. There is no relative motion between the differential case and the gears in the planetary drive train. The differential case is driven directly by the differential ring gear, the same as in the conventional single fixed gear final drive.When shifted into low range, the sun gear is slid out of mesh with the ring carrying the planetary gears. The dog clutch makes a rigid connection with the left bearing adjusting ring. Because the sun gear is integral with the dog clutch, it is also locked to the bearing adjusting rings and remains stationary. The internal gear rotates the planetary gears around the stationary sun gear, and the differential case is driven by the ring on which the planetary gears are pivoted. This action produces the gear reduction, or low speed, of the axleDIFFERENTIAL ACTIONThe rear wheels of a vehicle do not always turn at the same speed. When the vehicle is turning or when tire diameters differ slightly, the rear wheels must rotate at different speeds.If there were a solid connection between each axle and the differential case, the tires would tend to slide, squeal, and wear whenever the operator turned the steering wheel of the vehicle. A differential is designed to prevent this problem.Driving Straight AheadWhen a vehicle is driving straight ahead, the ring gear, the differential case, the differential pinion gears, and the differential side gears turn as a unit. The two differential pinion gears do NOT rotate on the pinion shaft, because they exert equal force on the side gears. As a result, the side gears turn at the same speed as the ring gear, causing both rear wheels to turn at the same speed.Turning CornersWhen the vehicle begins to round a curve, the differential pinion gears rotate on the pinion shaft. This occurs because the pinion gears must walk around the slower turning differential side gear. Therefore, the pinion gears carry additional rotary motion to the faster turning outer wheel on the turn..Differential speed is considered to be 100 percent. The rotating action of the pinion gears carries 90 percent of this speed to the slowing mover inner wheel and sends 110 percent of the speed to the faster rotating outer wheel. This action allows the vehicle to make the turn without sliding or squealing the wheels.Figure 5-15.—Two speed final drive汽车主减速器主减速器主减速器是在传动轴和差速器之间的一个动力传动系统的组成部分。

本科生毕业设计(论文)外文翻译毕业设计(论文)题目:汽车主减速器的对比分析与设计外文题目:AUTOMOTIWE FINAL DRIVE译文题目:汽车主减速器AUTOMOTIWE FINAL DRIVEFINAL DRIVEA final drive is that part of a power transmission system between the drive shaft and the differential. Its function is to change the direction of the power transmitted by the drive shaft through 90 degrees to the driving axlesAt the same timeit provides a fixed reduction between the speed of the drive shaft and the axle driving the wheels.The reduction or gear ratio of the final drive is determined by dividing the number of teeth on the ring gear by the number of teeth on the pinion gearIn passenger vehicles, this speed reduction varies from about 3:1 to 5:1. In trucks it varies from about 5:1 to 11:1. To calculate rear axle ratio, count the number of teeth on each gear. Then divide the number of pinion teeth into the number of ring gear teeth. For example, if the pinion gear has 10 teeth and the ring gear has 30 30 divided by 10, the rear axle ratio would be 3:1.Manufacturers install a rear axle ratio that provides a compromise between performance and economyThe average passenger car ratio is 3.50:1.The higher axle ratio, 4.11:1 for instance, would increase acceleration and pulling power but would decrease fuel economy. The engine would have to run at a higher rpm to maintain an equal cruising speedTheloweraxleratio 3:1,wouldreduce acceleration and pulling power but would increase fuel mileageThe engine would run at a lower rpm while maintaining the same speedThe major components of the final drive include the pinion gear, connected to the drive shaft, and a bevel gear or ring gear that is bolted or riveted to the differential carrierTo maintain accurate and proper alignment and tooth contact, the ring gear and differential assembly are mounted in bearingsThe bevel drive pinion is supported by two tapered roller bearings,mountedinthedifferentialcarrier This pinion shaft is straddle mountedmeaning that a bearing is located on each side of the pinion shaft teeth. Oil seals prevent the loss of lubricant from the housing where the pinion shaft and axle shafts protrude. As a mechanic, you will encounter the final drive gears in the spiral bevel and hypoid design.Spiral Bevel GearSpiral bevel gears have curved gear teeth with the pinion and ring gear on the same center line. This type of final drive is used extensively in truck and occasionally in older automobiles. This design allows for constant contact between the ring gear and pinion. It also necessitates the use of heavy grade lubricantsHypoid Gear The hypoid gear final drive is an improvement or variation of the spiral bevel design and is commonly used in light and medium trucks and all domestic rear- wheel drive automobiles. Hypoid gears have replaced spiral bevel gears because they lower the hump in the floor of the vehicle and improve gear-meshing action. As you can see in figure 5-13, the pinion meshes with the ring gear below the center line and is at a slight angle less than 90 degreesFigure 5-13.?Types of final drives This angle and the use of heavier larger teeth permit an increased amount of power to be transmitted while the size of the ring gear and housing remain constant. The tooth design is similar to the spiral bevel but includes some of the characteristics of the worm gear. This permits the reduced drive angle. The hypoid gear teeth have a more pronounced curve and steeper angle, resulting in larger tooth areas and more teeth to be in contact at thesame time. With more than one gear tooth in contact, a hypoid design increases gear life and reduces gear noiseThe wiping action of the teeth causes heavy tooth pressure that requires the use of heavy grade lubricants.Double-Reduction Final DriveIn the final drives shown in figure 5-13, there is a singlefixedgearreduction Thisistheonlygear reduction in most automobiles and light- and some medium-duty trucks between the drive shaft and the wheels.Double-reduction final drives are used for heavy- duty trucks. With this arrangement fig. 5-14 it is not necessary to have a large ring gear to get the necessary gear reductionThe first gear reduction is obtained through a pinion and ring gear as the single fixed gear reduction final drive. Referring to figure 5-14, notice that the secondary pinion is mounted on the primary ring gear shaft. The second gear reduction is the result of the secondary pinion which is rigidly attached to the primary ring gear, driving a large helical gear which is attachedtothedifferentialcase Double-reduction final drives may be found on military design vehicles, such as the 5-ton truck. Many commercially designed vehicles of this size use a single- or double-reduction final drive with provisions for two speeds to be incorporatedFigure 5-14.?Double-reduction final driveTwo-Speed Final DriveThe two-speed or dual-ratio final drive is used to supplementthegearingoftheotherdrivetrain components and is used in vehicles with a single drive axle fig5-15The operator can select the range or speed of this axle with a button on the shifting lever of the transmission or by a lever through linkageThe two-speed final drive doubles the number of gear ratios available for driving the vehicle under variousloadandroadconditions Forexample,a vehiclewithatwo-speedunitandafive-speedtransmission,tendifferentforwardspeedsare available. This unit provides a gear ratio high enough to permit pulling a heavy load up steep grades and a low ratio to permit the vehicle to run at high speeds with a light load or no loadThe conventional spiral bevel pinion and ring gear drives the two-speed unit, but a planetary gear train is placed between the differential drive ring gear and the differential caseThe internal gear of the planetary gear train is bolted rigidly to the bevel drive gear. A ring on which the planetary gears are pivoted is bolted to the differential caseA member, consisting of the sun gear and a dog clutch, slides on one of the axle shafts and iscontrolled through a button or lever accessible to the operator When in high range, the sun gear meshes with the internal teeth on the ring carrying the planetary gears and disengages the dog clutch from the left bearing adjusting ring, which is rigidly held in the differential carrierIn this position, the planetary gear train is locked together. There is no relative motion between the differential case and the gears in the planetary drive trainThe differential case is driven directly by the differential ring gear, the same as in the conventional single fixed gear final drive.When shifted into low range, the sun gear is slid out of mesh with the ring carrying the planetary gears. The dog clutch makes a rigid connection with the left bearing adjusting ring. Because the sun gear is integral with the dog clutch, it is also locked to the bearing adjusting rings and remains stationaryThe internal gear rotates the planetary gears around the stationary sun gear, and the differential case is driven by the ring on which the planetary gears are pivoted. This action produces the gear reduction, or low speed, of the axleDIFFERENTIALACTIONThe rear wheels of a vehicle do not always turn at the same speed. When the vehicle is turning or when tire diameters differ slightly, the rear wheels must rotate at different speeds If there were asolid connection between each axle and the differential case, the tires would tend to slide, squeal, and wear whenever the operator turned the steering wheel of the vehicleA differential is designed to prevent this problemDriving Straight AheadWhen a vehicle is driving straight ahead, the ring gear, the differential case, the differential pinion gears, and the differential side gears turn as a unit. The two differential pinion gears do NOT rotate on the pinion shaft, because they exert equal force on the side gears. As a result, the side gears turn at the same speed as the ring gear, causing both rear wheels to turn at the same speedTurning Corners When the vehicle begins to round a curve, the differential pinion gears rotate on the pinion shaftThis occurs because the pinion gears must walk around the slower turning differential side gearTherefore, the pinion gears carry additional rotary motion to the faster turning outer wheel on the turn Differential speed is considered to be 100 percent. The rotating action of the pinion gears carries 90 percent of this speed to the slowing mover inner wheel and sends 110 percent of the speed to the faster rotating outer wheel. This action allows the vehicle to make the turn without sliding or squealing the wheelsFigure 5-15.?Two speed final drive汽车主减速器主减速器主减速器是在传动轴和差速器之间的一个动力传动系统的组成部分。