Apparatus for blanking sheet materials

Apparatus for blanking sheets comprising:

• a press;
• a blanking die including an upper die holder mounted to said press and a lower die holder mounted to said press beneath said upper die holder, said upper and lower die holders having upper and lower rotary members detachably supporting upper and lower dies, respectively;
• means vertically reciprocating one of said upper and lower die holders relative to each other into sheet blanking cooperation;
• means associated with each of said upper and lower die holders and dies for rotating said upper and lower dies independently of one another and relative to said upper and lower die holders, respectively, said rotating means including a circumferential gear arranged about each rotary member, a hydraulic cylinder fixed to each of said die holders, each cylinder including a piston formed as a rack, the rack of each cylinder being engageable with the circumferential gear of its associated rotary member;
• and
• means for positioning a sheet to be blanked relative to said blanking die from a first processing position into a plurality of processing positions according to one of a plurality of predetermined processing patterns, said one processing pattern including numerical values of a starting position on an X axis and a Y axis, a pitch Px on said X axis, a pitch Py on said Y axis, a blanking number Nx on said X axis, blanking number Ny on said Y axis and a displacement Cx on said X axis of a second processing poition of said sheet.