Patent ID: 7347077
Filing Date: 2008-03-25
Classification: B21K,F16D

Abstract:
1. A method of manufacturing an outer race member for a tripod-type constant-velocity joint having a shank and a cup which are integrally formed by cold forging, comprising the steps of: extruding forwards a cylindrical workpiece cut to a predetermined length to form a primary formed body having a shank; preliminarily upsetting an upper portion of said workpiece except said shank thereof to form a secondary formed body; further upsetting an upper portion of said secondary formed body except said shank thereof to form an intermediate preliminary formed body having an annular slanted surface which provides a material-flow resistance difference between larger-diameter portions and smaller-diameter portions thereof; extruding backwards said intermediate preliminary formed body to form a quaternary formed body having a cup with track grooves defined therein; and ironing said cup of said quaternary formed body.