Constant velocity universal joint

A constant velocity universal joint comprising:

• an outer race having an inner, spherical, concave surface disposed about a longitudinal axis of said outer race,
• a plurality of arcuate, generally longitudinally extending, circumferentially spaced outer race grooves in said concave surface of said outer race,
• an inner race having an outer, spherical, convex surface disposed about a longitudinal axis of said inner race,
• a plurality of arcuate, generally longitudinally extending, circumferentially spaced inner race grooves in said convex surface of said inner race,
• said inner race being disposed concentrically within said outer race with said convex surface spherically engaged with said concave surface for relative angular movement of said inner and outer races about a common joint center,
• each of said inner race grooves being arranged opposite a corresponding one of the outer race grooves to define a plurality of ball-groove pairs,
• the grooves of each ball-groove pair being disposed in transverse crossing relation to one another, and
• a plurality of torque-transmitting balls, one of said balls being disposed in each of said ball-groove pairs for movement therealong during such relative angular movement of said inner and outer races, wherein the outer race grooves of all of the ball-groove pairs are inclined in one circumferential direction, and the inner race grooves of all of the ball-groove pairs are inclined in a direction which is opposite said one circumferential direction, wherein the outer race grooves of one or more of the ball-groove pairs have centers which are axially spaced from said joint center to one side of said joint center, the inner race grooves of said one or more of the ball-groove pairs have centers which are axially spaced from said joint center to a second side opposite said one side of said joint center, the outer race grooves of the ball-groove pairs other than said one or more of the ball-groove pairs have centers which are axially spaced from said joint center to said second side of the joint center, and the inner race grooves of the ball-groove pairs other than said one or more groove pairs have centers which are axially spaced from said joint center to said one side of the joint center.