汽车专业英语读译教程 作者 宋进桂_ 14-U8TB.ppt

UNIT 8 CLUTCHES,  MANUAL TRANSMISSIONS  AND DRIVE LINETEXT ADRIVE LINE  UNIT 7 CLUTCHES,  MANUAL TRANSMISSIONS  AND DRIVE LINETEXT A DRIVE LINE  ? Drive Shaft ? Universal Joint ? Final Drive ? Differential 本次课学习目标 掌握传动系统的有关英文专业词汇 能够较好地用已知翻译技巧进行课文翻译 训练快速阅读能力，较高的阅读速度 能够较熟练地运用“倒译法”。 NEW WORDS There are two basic CV joint types: tripod and Rzeppa (also called ball and channel) type, Both of these are constant velocity designs. The Rzeppa joint is by far the most common. Tripod Joint Figure 8-8 shows the tripod joint. It is composed of three trunnions inside of a three channel housing. Unlike the cross and roller universal joint, the tripod joint trunnions can slide back and forth in the channels as the joint rotates. This maintains the same drive angle through the joint, allowing power to be transmitted without speed fluctuations. Inboard CV joints are usually tripod joints. Rzeppa Joint Figure 8-9 illustrates the Rzeppa CV joint, which was invented in 1926 by Alfred H. Rzeppa. It consists of a series of balls in a slotted cross and housing assembly. During operation, the balls slide back and forth in the slots as the joint rotates. Since the drive angle through the joint is not subject to fluctuations, power flows smoothly through the joint at any angle. Outboard CV joints are usually Rzeppa joints. Final Drive The ring and pinion gears are used to transfer the engine power from the drive shaft to the rear wheels. In addition to transferring power, the ring and pinion must cause the power to make a 90° turn between the drive shaft and wheels. The ring and pinion must also provide the correct axle ratio. The pinion is the smaller driving gear; the ring is always the larger driven gear. Differential The rear wheels of a vehicle must turn at different speeds when rounding the slightest corner (outside wheel must roll farther).