FIXED-TYPE CONSTANT-VELOCITY UNIVERSAL JOINT

摘要

Provided is a fixed type constant velocity universal joint, in which track grooves of an outer joint member include: first track groove portions positioned on an interior side; and second track groove portions positioned on an opening side. Each of the first track groove portions includes an arc part having a curvature center that is positioned without being offset in an axial direction with respect to a joint center. The first track groove portions are inclined in a peripheral direction of the outer joint member with respect to a joint axial line and adjacent to each other in the peripheral direction with their inclination directions opposite to each other. Each of the second track groove portions is formed into a different shape from a shape of the each of the first track groove portions so as to increase an effective track length at a maximum operating angle. The each of the first track groove portions and the each of the second track groove portions are connected to each other at a position on the opening side with respect to the joint center. Track grooves of the inner joint member are formed so as to be mirror-image symmetrical with corresponding paired track grooves of the outer joint member with respect to a plane including the joint center at an operating angle of 0°. A pocket clearance is set within a range in which balls and pockets of a cage are fitted with both an interference fit and a clearance fit.