The universal joint is the universal joint, which is a part that realizes variable-angle power transmission. It is used to change the position of the transmission axis. It is the "joint" part of the universal transmission of the automobile drive system. The combination of universal joint and drive shaft is called universal joint transmission. The universal transmission device is generally composed of a universal joint and a transmission shaft, and sometimes there is an intermediate support, which is mainly used in the following positions: 1- universal joint; 2- transmission shaft; 3- front transmission shaft; 4- intermediate support. In universal joint fit, the rotation of a component (output shaft) around its own axis is driven by the rotation of another component (input shaft) around its axis.
According to whether the universal joint has obvious elasticity in the torsion direction, it can be divided into rigid universal joint and flexible universal joint. Rigid universal joints can be divided into unequal velocity universal joints (commonly used as cross shaft type), quasi-constant velocity universal joints (such as double joints) and constant velocity universal joints (such as ball cage universal joints). Xiang section) three kinds.