What is the Principle of a Universal Joint?

[AxelDella]

The principle of a universal joint is: The structure and function of a universal joint resemble the joints in human limbs, allowing the angle between connected parts to vary within a certain range. To meet the requirements of power transmission and accommodate the angle changes caused by steering and the up-and-down movement of the car during operation, the drive axle of front-wheel-drive vehicles often uses universal joints to connect the half-shaft and the wheel axle. A single universal joint cannot ensure that the instantaneous angular velocity of the output shaft matches that of the input shaft, which can easily cause vibration, accelerate component wear, and generate significant noise. Various types of constant-velocity universal joints are widely used in front-wheel-drive vehicles, with two constant-velocity universal joints per half-shaft. The universal joint closer to the transaxle is the inner half-shaft universal joint, while the one near the wheel axle is the outer half-shaft universal joint.