What are the classification of universal joints?

Universal joint classification:

1. Common universal joints can be divided into three types: unequal velocity joints, quasi-constant velocity joints, and constant velocity joints;

2. For unequal velocity joints, when the included angle between the two shafts connected by the universal joint is greater than zero, the output shaft and the input shaft transmit motion with a changing instantaneous angular velocity ratio, but the average angular velocity is the same;

3. Quasi-constant velocity joint refers to a universal joint that transmits motion at an equal instantaneous angular velocity at the designed angle, and transmits movement at an approximately equal instantaneous angular velocity at other angles;

4. Constant velocity universal joint, the universal joint where the output shaft and the input shaft connected to the universal joint transmit motion at the same instantaneous angular velocity.