METHOD FOR MANUFACTURING OUTER MEMBER FOR CONSTANT VELOCITY UNIVERSAL JOINT, AND DEVICE FOR MANUFACTURING THE SAME OUTER MEMBER

摘要

PROBLEM TO BE SOLVED: To improve the yield of a forged product at a low cost by reducing variations in the cup part depth, which are generated in forge-molding of the outer member for a constant velocity universal joint.;SOLUTION: The outer member for the constant velocity universal joint, which member integrally has a cup part and a shaft part extending from one end of the cup part, is manufactured by performing pre-molding that consists of forward extrusion (A), upsetting (B), and backward extrusion (C), and by performing ironing (D). In the backward extrusion (C), extrusion-molding of the body of a cup part 7 is carried out by pushing an inner die 22 into a solid large-diameter part 5, and further the opening side edge face is formed on the cup part 7 by pressing the opening side edge part 8a of the cup part 7 with a pressure die 23.;COPYRIGHT: (C)2008,JPO&INPIT