Patent ID: 6877408

Claim:
A press punching method for forming a plurality of through holes in a planar work piece to be punched by an electrically controlled operation of a press, the press punching method comprising the steps of: placing the work piece in said press between a die block and at least one punch block having a plurality of punches arranged along a line, wherein distances between the ends of the punches and the die block are different from each other; forming at least one first through hole in the work piece by punching the work piece by a part of the punches by moving at least one of said die block and said punch block until a first predetermined distance is formed therebetween; controllably moving the work piece in a direction perpendicular to an extended direction of said line of punches by a predetermined distance after disengaging the part of the punches from the work piece by separating said die block and said punch block from each other; detecting a position of the moved die block or punch block at which said first through hole occurred and supplying a signal in response to said detected position for subsequently moving said at least one of said die block and said punch block; and forming at least one second through hole in the work piece by punching the work piece by a part of the punches by moving at least one of said die block and said punch block until a second predetermined distance, different from said first predetermined distance, is formed therebetween, to produce a selected pattern of through holes in the workpiece.