Patent ID: 6305209
Filing Date: 2001-10-23
Classification: B21D,Y10T

Abstract:
A workpiece blanking apparatus comprising:a die;a pad for holding a plate of metal on said die;a blanking punch for depressing the plate on said die downwardly of the die to blank a workpiece out of the plate;a counterpunch vertically movably disposed in said die in confronting relationship to said blanking punch and movable downwardly with the workpiece blanked by said blanking punch;counterpunch urging means for normally urging said counterpunch upwardly; andholding means for holding said counterpunch in a lowered position after the workpiece is blanked by said blanking punch until said blanking punch is spaced from the workpiece, said pad is spaced from the plate, and said blanking punch and said pad are lifted to a predetermined position, and for releasing said counterpunch in said lowered position and allowing said counterpunch to displace said workpiece out of said die when said blanking punch and said pad are lifted to said predetermined position, wherein said holding means comprises:a pusher vertically movably disposed below said die for transmitting a biasing force from said counterpunch urging means to said counterpunch;a concave follower integrally mounted on an upper surface of said pusher;a slider disposed for movement along the upper surface of said pusher in a horizontal direction transverse to said counterpunch;a cam integrally projecting from a lower surface of said slider and movable into and out of engagement with said follower, for preventing said pusher from ascending upon movement into engagement with said follower and allowing said pusher to ascend upon movement out of engagement with said follower; andslider driving means for moving said slider horizontally in a direction to bring said cam out of engagement with said follower when said pusher is lowered in response to downward movement of said counterpunch depressed by said blanking punch, and for moving said slider horizontally in a direction to bring said cam into engagement with said follower when said blanking punch and said pad are lifted to said predetermined position.