What are the functions and characteristics of the universal joint drive shaft assembly?

The universal joint drive shaft assembly is a mechanical part that realizes variable-angle power transmission. It is used at the position where the direction of the drive shaft system needs to be changed. It is the "joint" part of the universal transmission of the automobile drive system.

On front-engine rear-wheel drive vehicles, the universal joint transmission is installed between the transmission output shaft and the drive axle final drive input shaft; however, the front-engine front-wheel drive vehicle omits the transmission shaft, and the universal joint is installed in Between the front axle half shaft and the wheels responsible for driving and steering.

The characteristics of the drive shaft assembly:
1: Exposed length of square tube (including protective hoop)
2: The center distance of the horizontal axis at both ends
3: The center distance of the pin holes at both ends
4: Total closed length at both ends