交通运输专业英语

1、Lesson 4 DrivetrainIn order to transmit the power of the engine to the road wheels of a motor car, a drivetrain is normally employed. Although the details of the drivetrains vary widely in different types of cars, the general principles are the same in all cases.为了把发动机的动力传递到机动车车的车轮，通常使用传动系统。尽管在不同类型的

2、汽车上，传动系统的细节有很大不同，但基本的原理都是一样的。in any case 无论如何in all cases 在任何情况下in either (every) case 在任何情况下 The clutch is a device to engage and disengage power from the engine , allowing the vehicle to stop and start.离合器是用来接合或分离发动机动力的装置，允许车辆停止或起动。A pressure plate or driving member is bolted to the engine flywhee

3、l and a clutch plate or driven member is located between the flywheel and the pressure plate.压盘或主动件用螺栓固定在发动机飞轮上，离合器片或从动件位于飞轮和压盘之间。The clutch plate is splined to the shaft extanding from the transmission or gearbox to the flywheel, commonly called a clutch shaft or input shaft.离合器片用花键与从传动系或变速箱伸向飞轮的轴（

4、通常称为离合器轴或输入轴）联接。spline词性及解释 n. 曲线尺, 齿条, 塞缝片, 花键 vt. 用花键联接, 开键槽 When the clutch and pressure plate are locked together by friction, the clutch shaft rotates with the engine crankshaft.当离合器和压盘由摩擦锁在一起，离合器轴就会随着发动机曲轴旋转。 Power is transferred from the engine to the transmission, where it is routed through

5、different gear ratios to obtain the best speed and power to start and keep the vehicle moving.动力由发动机传递到传动系，在这里通过采用不同齿轮齿数比以获得最优的速度及功率以起动或使车辆保持运行。1.1 the pressure plate The driving member is commonly called the pressure plate. It is bolted to the engine flywheel and its main purpose is to exert pressu

6、re against the clutch plate.主动件通常称作压盘。它由螺栓固定在发动机飞轮上，它的主要作用是对离合器片施加压力. It must also be capable of interrupting the power by releasing the pressure on the clutch plate. This allows the clutch plate to stop rotating while the flywheel and pressure plate continues to rotate.它必须能够通过释放离合器片上的压力来切断功率。这允许在飞轮

7、和压盘继续旋转时离合器片停止旋转。The pressure plate consists of a heavy metal plate, coil springs or a diaphragm spring, release levers, and a cover.压盘由一个厚金属盘、螺旋弹簧或膜片弹簧、分离杠杆以及离合器盖组成。When coil springs are used , they are evenly spaced around the metal plate and located between the plate and metal cover.当使用螺旋弹簧时，它们金属

8、盘上均布，且位于金属盘和离合器盖之间。 This places an even pressure against the plate, which in turn presses the clutch plate tight against the flywheel. The cover is bolted tightly to the flywheel and the metal plate is movable, due to internal linkages. 这样会在压盘上施加均匀压力，依次又会将离合器片压紧在飞轮上。离合器盖用螺栓紧连在飞轮上，由于内部的联接，金属盘可以移动。 Th

9、e coil springs are arranged to exert direct or indirect tension on the metal plate, depending upon the manufacturers design. 螺旋弹簧用于在金属盘上施加直接或间接的压力，这取决于制造商的设计。Three release levers (fingers), evenly spaced around the cover, are used on most pressure plates to release the holding pressure of the clutch

10、 plate, allowing it to disengage the power flow.在离合器盖上均布的三个分离杠杆，用于大多数压盘以释放离合器片上弹簧的保持压力，允许它切断动力。1.2 the clutch plateThe clutch plate or driven members consists of a round metal plate attached to a splined hub. The outer portion of the round plate is covered with a friction material of molded or woven

11、 asbestos and is riveted or bonded to the plate. rivet n. 铆钉 vt. 用铆钉固定, 敲进去, 注目, 吸引住bond n. 捆绑物, 结合, 债券, 契约, 粘合剂, 保证人, 键, 关栈保留 vt. 使黏合 vi. 结合离合器盘或从动件由与花键毂相连的圆金属盘组成。圆盘的外面覆盖着模压或编织石棉摩擦材料且分别通过铆接或粘接在圆盘上。The thickness of the clutch plate and /or facings may be warped to give a softer clutch engagement.离合器

12、片或贴面可以被弯曲以产生柔和的离合器接合。 Warpn. 变形, 弯曲, 歪曲, 乖僻, 偏差, 偏见 vt. 使变形, 弄歪, 使翘曲, 使不正常, 歪曲, 使有偏见 vi. 变弯, 变歪Coil springs are often installed in the hub to help provide a cushion against the twisting force of clutch engagement.螺旋弹簧经常被安装到在盘毂上以提供软垫帮助防止离合器接合时带来的圆周冲击力。 The splined hub is mated to a splined transmissi

13、on shaft when the clutch is engaged.当离合器接合时，花键毂与花键传动轴相配。The clutch pedal provides mechanical means for the driver to control the engagement and disengagement of the clutch.离合器踏板为司机提供离合器接合与分离的装置。 The pedal is connected mechanically to either a cable or rods, which are directly connected to the releas

14、e bearing lever.踏板或者与绳索或者与杆件机械式相连，它直接与分离轴承杠杆相连。When the clutch pedal is depressed, the linkage moves the release bearing lever. 当离合器踏板被踩下时，联动装置使分离轴承运动。 The release level is attached at the opposite end to a release bearing which straddles the transmission clutch shaft, and presses inward on the pres

15、sure plate fingers of the diaphragm spring.分离杠杆连接在分离轴承的反端，该轴承骑在传动系离合器轴上并且向内压在膜片弹簧压盘指上。 This inward pressure acts upon the fingers and internal linkage of the pressure plate and allows the clutch plate to move away from the flywheel, interrupting the flow of power. 这一向内的压力作用在分离指和压盘的内部连接装置上，允许离合器片从飞轮脱

16、开，切断动力。2 GearboxA higher torque is required to drive a heavily-loaded truck up a hill than that required to drive an empty truck on a flatroad. The engine will provide the necessary torque within a limited speed range. 重载货车爬坡比空车平路行驶需要更大的转矩。发动机会在有限的速度范围内提供必要的转矩。 The provision of a gearbox allows for

17、optimum utilization of the engine torque in driving the truck. In addition, the direction of the road wheels can be changed without the need for stopping the engine and restarting it in the reverse direction.变速器的供给在驱动货车的过程中，使得发动机转矩得到最优化的利用。此外，车轮的方向能够被改变，不需要停止发动机，在相反的方向重新启动发动机。There are two types of

18、gearboxes-manual and automatic.有两种类型的变速器手动的和自动的。The gearbox contains a number of gearwheels (Fig.4.2). If gearwheels of different size rotate in mesh with each other, the shaft of the larger wheel will rotate more slowly than that of the smaller wheel.变速器包含很多齿轮（图4.2）。如果不同尺寸的齿轮互相啮合进行旋转的话，大齿轮的轴要比小齿轮的轴

19、旋转地更慢。 If the smaller wheel is the one driving the assembly, the speed will therefore be reduced at the larger wheel. As a result the torque at the larger wheel will be greater by a corresponding amount.如果小齿轮是驱动总成的齿轮的话，因而在大齿轮上速度减小。结果大齿轮上的扭矩会相应的大一点。 A gearbox normally consists of an input shaft, a co

20、untershaft (layshaft) and an output shaft known as the main shaft. The engine torque is applied at the input shaft of the gearbox and is transmitted to the countershaft by means of a smaller gearwheel on the point shaft and a larger gearwheel on the countershaft.变速器通常是由输入轴，中间轴，和称为主轴的输出轴组成。发动机转矩施加到变速

21、器输入轴上，并且通过输入轴上的小齿轮和中间轴上的大齿轮传到中间轴。 The torque at the countershaft will thus be higher than the engine torque. Several gearwheels of different sizes are mounted on the countershaft and these can be combined with corresponding gearwheels on the output shaft. 因此中间轴上的转矩会比发动机转矩高。几个不同尺寸的齿轮安装在中间轴上，这些齿轮能够和输出

22、轴上的相应的齿轮接合。By this means, different increases in the torque supplied by the engine can be selected.通过这种方式，发动机所提供的转矩的不同增加可以被选择。 As an example, five stages can be selected in a five-speed gearbox. When the input and output shafts are coupled together, the torque of the engine will be transmitted throu

23、gh the gearbox without change. The required gear ratio is selected by means of the gear lever, which moves a sliding sleeve on the output shaft so that the appropriate gearwheels will mesh with the corresponding gearwheels on the countershaft.作为一个例子，在一个五速变速器中五级可以被选择。当输入轴和输出轴联接在一起的时候，发动机的转矩会通过变速器没有变化

24、地被传输。所需的速比用变速杆选择。变速杆移动输出轴上的滑动套，使适当的齿轮与中间轴上相应的齿轮啮合。To reverse the vehicle, the direction of rotation must be reversed and this is achieved by engaging an intermediate gearwheel located between the countershaft and the output shaft.为了使车辆反向，旋转的方向必须相反，这是通过在中间轴和输出轴之间啮合一个中间的齿轮来完成的。3 The propeller shaftThe

25、 propeller shaft transmits the drive from the gearbox mainshaft to the final drive pinion.传动轴把来自变速器主轴的驱动力传递到主减速器小齿轮。 The drive shaft is not solidly bolted to the gearbox and the final drive, which moves up and down with wheel-spring movement.驱动轴并不是坚固地用螺栓固定在变速器和随着车轮弹簧上下运动的主减速器上。 Two separate actions

26、are produced by this movement. First, the distance between the gearbox and the differential changes as the differential moves up and down.两个独立的作用是由这个运动所产生的。第一，在变速器和差速器之间的距离随着差速器上下移动而变化。As the springs compress and the differential moves up, the distance increases. As the springs expand and the differ

27、ential moves down, the distance decreases.当弹簧压紧，差速器向上运动时，距离增加。当弹簧膨胀，差速器向下运动时，距离减少。 Second, the driving angle changes as the differential moves up and down. Therefore, the shaft must have some allowance for motion between the final drive and gearbox.第二，传动角随着差速器上下运动而变化。因此，轴在主减速器和变速器之间运动时必须有一些公差The sha

28、ft is long so an intermediate shaft is additionally used. One end of the intermediate shaft is connected to the gearbox output shaft and the other, to the main propeller shaft.轴很长，因此需要额外地使用一根中间轴。中间轴的一端和变速器输出轴相连，另一端与主传动轴相连。The intermediate shaft rotates in a center bearing consisting of a support, a

29、rubber pillow and a ball bearing (Fig.5.1).中间轴以一个支承点为中心旋转，这个中心支承点由支座橡皮垫座和球轴承组成（图5.1）。3.1 Slip JointSince the propeller shaft tends to shorten and lengthen with the up-and-down differential movement, a device must be included to permit this action.由于传动轴随着差速器上下运动而趋于缩短和加长，那么必须包括一个允许这种动作的装置。 The device

30、used is called a slip joint. It is located either at the front or at the rear of the propeller shaft.这个使用的装置被称为滑动连接。它或者位于传动轴的前部或者位于传动轴的后部。 It consists of the externally splined slip yoke and the internally splined front shaft. When the slip joint is assembled, the yoke enters the shaft.它是由外部用花键接合的滑动

31、叉和内部用花键接合的前轴组成。当滑动连接装配好时，叉进入轴。 The two must turn together because of the splines. However, the yoke can slip in the shaft to shorten or lengthen the effective length of the propeller shaft.这两者由于花键必须一起转动。然而，叉能够在轴内滑动，以缩短和加长传动轴的有效长度。3.2 Universal JointsTo take care of the differences in the angle of dr

32、ive as the differential moves up and down, the propeller shaft has one or more universal joints. It is essentially a double-hinged joint through which the driving shaft can transmit power to the driven shaft, even though the two shafts are somewhat out of line with each other. 为了照顾随着差速器上下运动传动轴之间的差异，

33、传动轴有一个或者两个万向节。它实质上是一个双铰链连接，驱动轴能通过它把动力传给被动轴，尽管这两根轴并不完全在一条直线上。Each of the two shafts has a Y-shaped yoke on the end. Between the yokes is a center member shaped like a cross. The four arms of this cross member are assembled in bearings in the ends of the shaft yokes. The bearings permit the cross-memb

34、er arms to turn in the yokes. The driving shaft causes the cross member to rotate in with it. At the same time the cross member causes the driven member to rotate.这两根轴中每一根轴在末端都有一个Y形的叉。在两个叉之间有一个十字形的中心件。这个横粱的四个臂在轴叉的末端装配在支承点上。支承点允许横梁臂在叉内转动。驱动轴引起横梁随着驱动轴旋转。同时横梁引起从动件旋转。To take care of the differences in t

35、he angle of drive as the differential moves up and down, the propeller shaft has one or more universal joints.为了照顾随着差速器上下运动传动轴之间的差异，传动轴有一个或者两个万向节。 It is essentially a double-hinged joint through which the driving shaft can transmit power to the driven shaft, even though the two shafts are somewhat o

36、ut of line with each other. 它实质上是一个双铰链连接，驱动轴能通过它把动力传给被动轴，尽管这两根轴并不完全在一条直线上。4 The Rear Axle4.1 The Final DriveThe engine crankshaft being arranged at right angles to the rear axle, it follows that at the back axle some form of gearing must be provided to transmit the power to each of the rear wheels,

37、and at right angles to the propeller shaft.发动机曲轴和后轴成直角，因此必须在后轴上安装某种类型的齿轮装置，以便把动力传递到其轴线与传动轴成直角的每个后轮上。 There are several forms of gearing which allow power to be transmitted form one shaft to another at right angles to it, and without any appreciable loss of power.有几种形式的齿轮装置，这几种形式的齿轮装置允许把动力从一根轴传递到与其成直

38、角的另一根轴，没有任何明显的功率损失。The final drive is designed to give a reduction ratio of between 4:1and 5:1 in modern cars, so that the rear wheels are thus driven at 1/4 to 1/5of engine speed when top or direct drive gear is engaged in the gearbox.在现代轿车上主减速器被设计，以提供在4：1和5：1之间的减速比，以便当顶部驱动齿轮或直接驱动齿轮与变速器相啮合时，后轮以1/4到

39、1/5的发动机转速被驱动。 The principal types employed in motor-car practice are (1) The Bevel Gear, and (2) The Worm and Worm Wheel.在汽车惯例中使用的主要类型是：（1）锥齿轮，（2）蜗杆和蜗轮。 In the case of the bevel gear, which consists merely of two toothed cones meshing together, their axles meeting in a point, a smaller bevel gear attached to the rear end of the propeller shaft or its flexible coupling, meshes with a large bevel, known as the Crown Wheel which is attached to a gearing, known as the differential gear, driving the two rear wheels.就锥齿轮来说，它不过是由两个啮合在一起的带齿锥体所组成，这两个