Thrust washer for universal joint

Abstract

A universal joint assembly includes a cross having a plurality of trunnions extending outwardly therefrom. A bearing cup is disposed about each of the trunnions, and a plurality of needle bearings is disposed between each of the bearing cups and its associated trunnion to facilitate relative rotational movement. A thrust washer is disposed between the outer end surface of each of the trunnions and its associated bearing cup. Each of the thrust washers is generally annular in shape, including a first inner annular region surrounded by a second outer annular region. The inner region is sized to extend between the outer end surface of the trunnion and the associated inner surface of the end portion of the bearing cup. The outer region is sized to extend between the outer ends of the needle bearings and the associated inner A surfaces of the end portions of the bearing cup. The outer region is connected to and supported on the inner region by a plurality of radially extending legs. The inner region of the thrust washer is formed from a first material, while the outer region of the thrust washer is formed from a second material that is different from the first material. The inner region is preferably formed from a first material that is suited to withstand the relatively large loading stresses experienced between the trunnion and the bearing cup during use. The second region is preferably formed from a second material that is suited to lubricate the needle bearings during use. It is desirable that the first and second materials be capable of being molded together simultaneously to form the integral thrust washer.