Method of making a cage for use in a roller bearing

Abstract

A method of making a cage for use in a roller bearing comprises the steps of forming an inner circumferential groove centrally in an annular-shaped workpiece made of metal to define a circumferentially-extending side ring section on either side of the groove, punching the workpiece to form a plurality of axially-extending, circumferentially spaced-apart pockets for receiving rollers, and roughly abrading the outer peripheral surface of the workpiece. The punching and abrading steps inherently cause the outer peripheral surface of the workpiece at the side ring sections to become wavy, with a plurality of alternating recessed and raised portions. As a result of the abrading step, the difference in depth between the tops of the raised portions and the recessed portions is in the range of between approximately 60 .mu.m to 70 .mu.m. Accordingly, the outer peripheral surface of the workpiece is super finished to provide the tops of the raised portions with a cylindrical surface with a constant radius of curvature, while preserving the recessed portions. The workpiece is then split into two halves, following the super finishing step. As a result of the super finishing step, the difference in depth between the cylindrical surface and the recessed portions is in the range of between approximately 5 .mu.m to 50 .mu.m.