US Patent 8231184 Crawler track roller with internal spherical spacers

An endless track support roller is mounted for rotation about a shaft adapted for being fixed between parallel rails of a track support frame. The roller comprises mirror image halves, with a pair of thrust bushings being received on the shaft and respectively disposed in supporting relationship to the roller halves. Each thrust bushing includes an axially outwardly facing thrust face. Mounting brackets fixed to opposite ends of the shaft are adapted to be fixed to the pair of frame rails. Non-uniform edge loading of the bushings resulting from shaft deformations caused by flexure of the frame rails is minimized by providing axially inwardly facing ends of the brackets with spherically contoured surfaces, and by locating an annular spacer between each bracket and bushing thrust face, the annular spacer having outer and inner axially facing surfaces respectively shaped complimentary to the spherically contoured bracket surface and to the bushing thrust face.