TRIMMING DIE FOR FRONT HUB

PURPOSE:To perform the punching of a shaft hole and burring in one stage by actuating an upper die cushion as well as punching a shaft hole by a punch and providing a burr presser on the male die main body freely movable therewith, in the case of shaping the semi-finishing article for a front hub with trimming male and female dies. CONSTITUTION:This device is composed of the main part of a rim holder 1, die set main body 4, movable part 5, an upper part die cushion 6, male die 14 and female die 14. A front hub semi-finishing article, etc., is placed on a cradle 8. With pushing down the male die 14 the male die 14 is engaged with the semi-finishing article 9 and a burr presser 18 is brought into contact with the upper face of a burr 19. With further descent of the male die 14 a shaft hole is punched by a punch 7 and a core is released to the external part from a forced discharging hole 17. The burr 19 is cut between a blade part 14 and the outer peripheral edge of the male die by the descent of the male die 14 succeeding simultaneously therewith. The burring of the semi-finishing article and the shaft hole punching as well can be performed in one forming stage.