Patent ID: 7032490

Claim:
A punch for making a plurality of openings comprising: a frame having a length in a first direction; a plurality of punch blocks, each punch block fixed in the frame in the first direction and moveable in the frame in a second direction perpendicular to the first direction, each punch block comprising: a first guide surface facing opposite the second direction, the first guide surface spanning from one end of the punch block to the other end along the first direction and being further in the second direction at the two ends of the punch block than at the middle of the punch block; at least a punch head facing the second direction; a retracting mechanism for urging the punch block in opposite the second direction to an initial position; a slider movable along the frame in the first direction; a protrusion connected to the slider at a position to engage the first guide surface of each punch block; wherein when the slider moves in the first direction along the frame, the protrusion pushes the first guide surface near the middle of the punch block moving the punch block in the second direction.