PURPOSE: To easily manufacture a male die of high accuracy by facilitating the precise forming of the main part by manufacturing a male die by dividing into a main body part and the core member including a bearing part and assembling both separatably.
CONSTITUTION: A male die 1 is composed of a discoid male die main body 1A and the core member 1B assembled to the main body 1A. The leading hole 13 of an extrusion material is formed on the male die main body 1A and on the other hand, a slit-like core member fitting hole 14 is formed at the center part. On one side edge of the core member 1B, numerous hollow part forming projecting pieces 11 are provided in a row by leaving the gap of the extrusion forming material leading groove part among each other. And yet the bearing part 11a corresponding to the hollow part of the porous pipe is formed at the part of the forming projection piece 11. The forming of the bearing part 11a of the forming projection piece 11 which is the important part of the core member 1B and the neck part of the leading groove tip adjoining therewith can be thus executed without any trouble by wire cut discharge machining.
SUGIO EIJI
TANIGAWA MASAKAZU
