Patent ID: 7654908

Claim:
A tripod type constant velocity universal joint, comprising: an outer joint member including three track grooves axially extending on an inner circumferential surface thereof; an inner joint member having three radially projecting trunnions; a boot fitted to an outer periphery of the outer joint member at an end portion and to a shaft extended from the inner joint member at another end portion so as to seal an inner region of the joint; wherein the outer joint member includes a first reduced-thickness portion on an outer periphery thereof in a region corresponding to the region between the track grooves and having a first axial length, and a second reduced-thickness portion on the outer periphery thereof in a region corresponding to the region where the track grooves are located and having a second axial length, said first axial length and said second axial length being substantially equal; wherein three of each of the first reduced-thickness portion and the second reduced-thickness portion are configured to alternately align in a circumferential direction at positions equally dividing a circumference of the outer joint member into six axially extending reduced-thickness portions of substantially equal length, each of the six axially extending reduced-thickness portions being separated by a maximum rotating diameter portion of the outer joint member; and the second reduced-thickness portion is of a groove shape axially extending with respect to the outer joint member.