Punching press

A punching press comprising:

• a frame having a bolster plate;
• a slide element for pressing against said bolster plate and having a hole through the central portion of said slide in the direction of pressing;
• a crank comprising a crank shaft rotatably mounted to said frame above the bolster plate and slide, said crank further comprising a crank pin carried upon two crank arms, said arms having identical planar profiles in the plane perpendicular to said crankshaft and having circumferential bearing surfaces;
• a flywheel and clutch assembly mounted at one end of said crank shaft;
• a cam attached to the end of said crankshaft which is opposite said flywheel and clutch assembly;
• lever means movably mounted on said frame and actuated by said cam to eject finished work;
• two pressure rods, said rods having bearing means at an upper end, the lower ends of said rods being attached to said slide with one rod on each side of said hole in the slide;
• spring means, attached between the upper ends of said pressure rods and the frame, said spring means providing resilient bias of the rods and slide to an upward position, and resiliently retaining said rods and said slides in said upward position;
• a punching ram slidingly movable within the hole in the slide;
• and
• a connecting rod mounted on said crank pin and pivotally connected to said punching ram, said two pressure rods being spaced on each side of the connecting rod with the upper bearing ends of said rods in contact with the circumferential bearing surfaces on the respective crank arms, whereby rotation of said crank shaft causes the crank arms to force the pressure rods downward, thereby forcing said slide against said bolster plate so as to provide a pressing stroke, said crank pin being located within the profile of said crank arms to provide a punching stroke for said connecting rod and said ram, whereby both pressing and punching strokes are provided during one rotation of said crank shaft.