汽车专业英语(幻灯片)Chapter 5 AT(3.3.25).ppt

3.3.4 Automatic Transmission(AT),Review 1:List the parts of Automatic Transmission(AT).,1）Automatic transmissions(AT)Automatic transmissions have three basic systems-a torque converter,a gear system,and a hydraulic system.These fit together in a unit that fastens directly behind the engine.Fig.3-9.The front section of the transmission houses the torque converter.The torque converter is like the clutch in a manual transmission.It is the coupling between the engine and drive train that transmits power to the drive wheels.,自动变速器由液力变矩器、齿轮机构和液压控制系统等三个基本系统组成，它们组合在一起，直接安装在发动机后（图3-9）。液力变矩器位于变速器的前端，它类似于手动变速器里的离合器，布置在发动机和传动系之间，向驱动轮传递动力。,Review 2:Whats the theory of hydrodynamic coupling?,Parts of Torque Converter,Review 3:List the parts of Planetary Gear system.,2）planetary gears:The planet gears are actually one set of gears joined together by a cage called the planet gear carrier or planet pinion carrier.The carrier has pins that go through the center of each of the planet gears.Thus,all the planet gears move together when the planet carrier moves.Each planet gear can turn around its pin when the planet gear carrier is stationary.,行星齿轮机构是一组齿轮，由行星架将这些齿轮组合在一起。行星架上有销穿过每个行星轮的中心。当行星架运动时，所有的行星轮也随之运动。当行星架固定时，行星轮绕销转动。,Review 4:How the Planetary Gear system works?,3）how the planetary system work:The planetary system works on the following principles:With one part held stationary,torque and power can be applied to a second member to make a third member rotate.In other words,with one of the three members held stationary,torque is applied to either of the other two members and output torque is delivered from the third member.,行星齿轮系的工作原理如下：当一个部件固定时，扭矩和动力会施加给第二个部件，从而带动第三个部件旋转。也就是说，在三个部件中只要使一个部件固定，扭矩会传递给其它两部件的任何一个部件，动力就会从第三个部件输出。,4）ring gear stationary(gear reduction):When you hold the ring gear and apply torque to the sun gear,the planet carrier turns in the same direction as the sun gear.However,the carrier turns at a much slower speed.As Fig.3-7 shows,the carrier makes less than half a revolution in the time the sun gear makes a complete revolution.If the planet carrier were connected to an output shaft,that shaft would also turn slower than the input shaft connected to the sun gear.This causes gear reduction on the output shaft.Of course,the gear reduction also causes torque multiplication of the output shaft.,如果保持齿圈固定，给太阳轮施加力矩，行星架就随太阳轮同向旋转。然而行星架转速比太阳轮低得多。如图3-7所示，太阳轮转一圈时，行星架会慢半圈。如果行星架连到输出轴上，输出轴比连接太阳轮的输入轴要转得慢，输出轴上得到降挡，转速会降低，当然输出轴上的扭矩会增加。,5）sun gear stationary:Now hold the sun gear stationary and apply input torque to the ring gear.The planet carrier again becomes the driven member and the source of output torque.In this case,the planet gears walk around the sun gear.As Fig.3-10 shows,the gear carrier turns more slowly than the ring gear.The carrier makes a little more than half a revolution in the time the ring gear makes one complete revolution.The ratio of these two parts depends on the number of teeth in the planet gears and ring gear.Since the output(gear carrier)rotates more slowly than the input(ring gear),there is gear reduction,and gear reduction results in torque multiplication.,如果保持太阳轮固定，给齿圈施加力矩，行星架作为从动装置输出动力。这样行星轮绕太阳轮旋转。如图3-10所示，行星架比齿圈转得慢。齿圈转一圈时，行星架会慢半圈。传动比由行星轮和齿圈的齿数决定。由于输出轴比输入轴转得慢，得到降挡，转速降低扭矩增加。,6）planet carrier stationary(reverse):Now hold the planet carrier stationary and apply input torque to the sun gear.Now the planet gears idle(rotate)in the opposite direction as the sun gear.The rotating planet gears cause the ring gear to rotate at a slower speed than the sun gear.The ring gear turns in the opposite direction as the sun gear.This is an example of reverse gear-the output shaft turns in the opposite direction as the input shaft.Since the ring gear(output)turns more slowly than the sun gear(input),there is also gear reduction.,如果行星架保持固定，给太阳轮施加力矩，行星轮随太阳轮反向空转。行星轮的转动使环齿比太阳轮转得慢，齿圈与太阳轮转向相反。输出轴与输入轴反向旋转，得到倒挡。由于环齿比太阳轮转得慢，也得到降挡。,7）all members connected(direct drive)Lock together any two members of the system,and the planet gears can neither idle nor walk about the sun gear.For example,imagine that the sun gear is locked to the planet carrier.Apply torque to any one of the three members and take output torque from one of the other members.Now the entire gear system rotates together at the same speed.Now the input shaft and output shaft rotate at the same speed,with no multiplication or reduction in torque.When any two members lock together and rotate,there is a 1:1 ratio(direct drive ratio).,如果行星齿轮系中的任意两个部件锁止在一起，行星轮既不能空转也不能绕太阳轮旋转。举例来说，假如太阳轮与行星架锁定，给轮系中的任意一个部件施加力矩，动力会从其它某一部件输出。整个行星齿轮系以相同速度旋转，扭矩不会发生变化，得到1:1的直接挡。,8）no members connected(neutral):In the examples discussed so far,at least one member of the system was held in place or locked to another member.This allows us to apply input torque at one point and take output torque from another point.If you do not lock any members,all parts turn freely.When all parts turn independently of one another,the planetary gear system is in neutral.,迄今为止，在我们讨论的例子中，行星轮系中至少有一个部件固定或同另一个部件锁止在一起，这样一个部件输入扭矩，另一个部件会输出扭矩。如果所有的部件都不锁止在一起，所有的部件都会自由旋转。所有的部件都独立于其它部件转动，行星轮系就处于空挡位置。,Review 5:List the operation of Automatic Transmission(AT).,PParking 驻车RReverse 倒挡NNeutral 空挡DDrive 前进挡2(S)Second 强制2挡1(L)Low 强制一挡,Review 6:Whats the meaning of AMT?,AMT Automatic Manually Transmission（电控机械自动变速器）,Review 7:Whats the meaning of CVT?,CVT Continuously Variable Transmission（无级变速器）,Review 8:Whats the meaning of Tiptronic/Multitronic?,Polo 6-speed,第一种是以传统自动变速器技术为基础，另外加装电子和液压控制装置，允许手动换档；第二种是CVT变速器，人为地将无级变速划分出几个区域，允许手动换档；第三种是以手动变速箱为基础，把离合器的自动控制和电子液压顺序换档相结合；第四种是DSG直接换档变速器。还有一种是手动+自动，即将普通“H”型换档方式的手动变速器和自动离合器相结合，也可称作半自动。,手自一体变速器的主要形式,Other manufacturers use Tiptronic-like systems,Acura（本田阿库拉/讴歌）:Sequential Sport Shift 带有运动换挡模式的手自一体变速箱;BMW:Steptronic带有手动换挡功能的6速手自一体变速箱；Jaguar（美洲虎）:Bosch Mechatronic电动混合动力换档机械；Lexus（雷克萨斯）:E-Shift Mercedes-Benz(梅赛德斯-奔驰):TouchShift Mitsubishi（三菱）:Sportronic Volvo:Geartronic.,