The characteristic of the simple cardan joint is to transmit incoming motion in a uniform manner and outgoing motion in a non-uniform manner. With the semi-joint on the motor side at constant speed, the other semi-joint will have a periodic motion but with the same average speed.
When the fork on the motor side is turned by a fraction of a revolution, the fork on the driven side will also turn by a fraction, but the angle of rotation on the driven side ?2 differs from the angle of rotation ?1 of the semi-joint on the motor side, according to the following ratio:
tan φ 2 = tan φ 1 : cos ß
The angular speed of the two semi-joints is directly influenced by the fact that the driven semi-joint rotates slightly in advance in the first quarter turn and slightly in delay in the second quarter
For more information please visit the Cardan Shaft section in our web page: