Hole punch mount for split rotary die punches

A punch and die assembly for a rotary forms press, for punching a plurality of spaced apart holes in a sheet of material as the sheet is conveyed between a punch sub-assembly and a die ring sub-assembly carried by the punch and die assembly, comprising:

• (a) the punch sub-assembly comprising a hub, fixedly mounted on a punch shaft for driven rotation therewith and including;
• (i) a split punch ring of multiple segments having an outer periphery mounted on the hub;
• fastening means connecting the multiple segments of the split punch ring about the hub;
• a plurality of relatively hard punches generally equidistantly disposed about the outer periphery of the punch ring and protruding therefrom;
• means securing the punches in position on the punch ring;
• with the split punch ring having an inner generally cylindrical surface and with the hub having an outer generally cylindrical surface;
• with said cylindrical surfaces being in slip fit engagement, said slip fit engagement allowing relative rotational movement between said punch ring and hub for accommodating minor rotary repositioning of the punch ring and punches carried thereby to cut holes in the sheet of material;
• and
• (b) the die ring sub-assembly having an outer periphery, the die ring sub-assembly including;
• (ii) multiple die segments that together comprise a cylindrical member, mounted on a die shaft;
• fastening means connecting the multiple segments of the die ring sub-assembly as a split die ring about the die shaft;
• and the die ring sub-assembly having a plurality of hard die openings generally equidistantly disposed about the outer periphery of the die ring sub-assembly wherein there are axial-motion-limiting means protruding radially between said punch ring and said hub for limiting axial movement of said punch ring relative to the hub, and wherein clearance is provided, associated with said axial-motion-limiting means, for accommodating minor axial repositioning of the punch ring and punches carried thereby as punches enter the holes of said die ring sub-assembly with which they will engage to cut holes in the sheet of material.