Press die assembly and method for producing the same

Abstract

A press die assembly is efficiently produced by: fabricating a press die pattern having therein grooves extending along concave corner portions thereof corresponding to concave corner portions of a product forming surface in the die of the press die assembly; fabricating a cast blank of the die by a full-mold method by using the press die pattern; and machining and finishing the product forming surface of the cast blank by utilizing the grooves as clearance space for the machining and finishing tools to obtain the finished die. In the press forming operation of the press die assembly, the grooves permit the sheet blank being press formed to slip thereby to eliminate local stretching, whereby high-quality pressed products are obtained. The grooves enables an easy machining by a tool.

Dependencies are inferred from the claim text.