Patent ID: 8474296
Filing Date: 2013-07-02
Classification: B21D

Abstract:
1. A punching machine comprising a formation tool having an upper die tool and a lower die tool and including structure which supports a sheet metal workpiece for movement between the upper die tool and the lower die tool in a punching stroke plane, a cylindrical recess, the lower die tool being positioned at the top of the cylindrical recess and a hollow tubular body which fits into the cylindrical recess, the upper die tool having a recessed mold part, the lower die tool having a stripper plate with an upper stripper surface located at or below the punching stroke plane, the lower die tool having a male mold part which is initially located below the upper stripper surface, the hollow tubular body engaging the bottom of the male mold part, wherein when the male mold part is raised, it mates with the recessed mold part of the upper die tool to deform the sheet metal located between the upper die tool and the lower die tool, the male mold part being movable upwardly across the punching stroke plane to deform the sheet metal above the punching stroke plane and against the interior of the recessed mold part of the upper die tool, the top of the hollow tubular body operatively engaging the male mold part and a powered lifting device engaging the bottom of the hollow tubular body to move the hollow tubular body upwardly to in turn raise the male mold part to mate with the upper die tool.