The angle of the universal joint should be minimized when designing
a. When the relative position of the connecting two shafts changes within the expected range, the power can be reliably transmitted;
b. Connecting two shafts can run evenly.The additional load, vibration and noise caused by the included angle of the universal joint should be within the allowable range;
c. High transmission efficiency, long service life, simple structure, convenient manufacture and easy maintenance.For automobiles, since the output shaft of a cross-shaft universal joint rotates at unequal speeds relative to the input shaft (with a certain included angle), a double universal joint (or multiple universal joint) transmission must be adopted for this purpose. The two universal joint forks connected with the drive shaft are arranged on the same plane, and the angles of the two universal joints are equal.This is very important.In the design, the angle of the universal joint should be minimized.