The universal joint we are talking about is a mechanical structure that uses ball-shaped connections to realize the power transmission of different shafts. It is a very important part of the car. However, there are many types of universal joints, so for those who don't know much about it, custom universal joints are a very convenient choice.

There are many classifications of universal joints, one of which is the ball and cage type constant velocity universal joint. According to whether the universal joint can move in the axial direction, it can be divided into the axially non-telescopic (fixed) ball type universal joint and the retractable ball-type universal joint.

Structurally, the inner surface of the star sleeve of the fixed ball cage universal joint is connected to the drive shaft with inner splines, and its outer surface has 6 arc-shaped grooves as the inner raceway of the steel ball, and the outer raceway is made in On the inner surface of the spherical shell. A steel ball is installed in each of the 6 raceways formed by the assembly of the star sleeve and the spherical shell, and the 6 steel balls are in the same plane by the cage (ball cage). The power is transmitted from the drive shaft through the steel ball and spherical shell (Figure 2).

The structural feature of the retractable ball cage universal joint is that cylindrical straight grooves are made on the inner wall of the cylindrical shell and the outer part of the star sleeve, and steel balls are installed in the raceway formed by the two assembled. The steel ball is also installed in the hole of the cage. The inner hole of the star sleeve is splined to connect with the input shaft. This structure allows the star sleeve and the simple shell to move in the axial direction relative to each other.

For more details, please visit universal joint for truck .