The transmission shaft is composed of a shaft tube, a telescopic sleeve and a universal joint. The change of the distance between the transmission and the drive axle can be adjusted automatically by the telescopic sleeve. Universal joint is to ensure the transmission output shaft and a driving input shaft axis and two axis angle changes, and to realize the two axis angular velocity transmission.
Universal joint is the key part of automobile transmission shaft. In the front engine, rear wheel drive vehicles, the universal joint drive shaft is installed in the transmission output shaft and drive axle main reducer input shaft between; front engine front drive vehicle omits the transmission shaft, universal joint installation is responsible for driving and be responsible for steering the front axle shaft and between the wheels.A car is a moving object.The engine, clutch and transmission are installed on the frame as a whole, and the drive axle is connected with the frame through an elastic suspension, and a distance between the two is needed to be connected. Vehicles running on road surface uneven producing tiaodong, load change or two assembly installation position difference, the transmission output shaft and driving axle main reducer input shaft between the angle and distance change, so it is in a “strain” device to solve this problem, so there is an universal joint.