Patent attributes
A constant velocity joint 10 comprises an outer race 12, an inner race 11, balls 14 and a cage 13. The outer race 12 has a partially spherical inner surface 12a provided with plural outer ball grooves 12b. The inner race 11 has a partially spherical outer surface 11 a provided with plural inner ball grooves 11b arranged to correspond to the outer ball grooves 12b. The balls 14 are interposed between the outer ball grooves 12b and the inner ball grooves 11b. The radial distance of the outer ball grooves 12b from the rotational axis of the outer race increases toward an opening end of the outer race 12 in a predetermined zone H, and a contact angle θ between each ball 14 and each outer ball groove 12b decreases toward the opening end of the outer race 12 in the predetermined zone H.
