The structure and function of the custom universal joints is a bit like the joints on the limbs of the human body. Its existence can allow the angle between the connected parts to change within a certain range, which can meet the requirements of power transmission, steering and vehicle operation. The angle change caused by the resulting up and down jump. For example, the drive axle of the front drive car, the universal joint is often suitable between the half axle and the axle.

For a single universal joint, due to the limitation of the axial size, such a universal joint can not make the instantaneous angular velocity of the output shaft and the shaft into the shaft equal, it is easy to cause vibration, each part is more likely to be damaged, and it will also produce huge noise. Therefore, various constant velocity universal joints are currently widely used in the market.

When a constant velocity joint is applied to a front-drive vehicle, two constant velocity joints are used for each half axle. The joint near the transaxle is the inner joint of the half axle, and the one near the axle is the outer half of the axle. Xiangjie. On the rear drive car, the engine, clutch and transmission are installed on the frame as a whole, and the drive axle is connected to the frame through an elastic suspension. There is a distance between the two, which needs to be connected with a universal joint.

During the operation of the car, the jitter caused by the uneven road surface, the load change or the difference between the two assembly installations, etc., will make the angle and distance between the transmission output shaft and the input shaft of the main reducer of the drive axle occur Change, so the universal joints of rear-drive cars mostly use double universal joints, that is, there are one universal joint at each end of the transmission shaft. The function of the double precision universal joint is to make the angle between the two ends of the transmission shaft equal, so as to ensure that the instantaneous angular velocity of the output shaft and the input shaft are always equal.