Patent ID: 7090729
Filing Date: 2006-08-15
Classification: B21K,F16D

Abstract:
1. A method of manufacturing an outer ring member for a constant velocity joint having a shaft section and a cup section integrally, said method comprising the steps of: forming said shaft section by forward extrusion to a workpiece having a surface with a lubricating chemical conversion coating; forming a diametrally expanded section by upsetting a portion of said workpiece except for said shaft section, and then forming an intermediate preformed product having a cup section with an incomplete shape by pressing said diametrally expanded section without a low temperature annealing treatment, a shot blast treatment and a lubricating chemical conversion coating treatment; applying a low temperature annealing treatment, a shot blast treatment and a lubricating chemical conversion coating treatment to said intermediate preformed product and thereafter forming a formed product having said cup section provided with grooves by backward extrusion to said intermediate preformed product; and subsequently ironing said formed product before work hardening in said formed product without applying a low temperature annealing treatment, a shot blast treatment and a lubricating chemical conversion coating treatment to said formed product.