FIXED-TYPE, CONSTANT-VELOCITY UNIVERSAL JOINT

摘要

Provided is a fixed type constant velocity universal joint capable of securing a ball groove depth larger in comparison with that of conventional products and enhancing performance without an increase in a “force of pushing out balls in an axial direction”, the force having an influence on joint efficiency. A ratio (F/PCR) of an offset amount F to a length (PCR) of a segment connecting the center of each of the guide grooves (22, 25) and a center of each of balls (27) to each other ranges from 0.045 to 0.065. A ratio (αt/α) ranges from 0.045 to 0.065 on a premise that an angle formed between the following is αt: a segment connecting a center of an outer surface of a retainer (28) and the center of each of the balls to each other; and the segment connecting the center of each of the guide grooves of the outer joint member and the center of each of the balls to each other, that an angle formed between the following is αc: a line connecting the center of the outer surface of the retainer and the center of each of the balls to each other; and a line connecting a joint center and the center of each of the balls to each other, and that a total of the angles is α.