Container closure forming apparatus and method

Claim 1

APPARATUS FOR FORMING A CONTAINER CLOSURE OF THE TYPE HAVING A TOP, A DEPENDING ANNUAL SKIRT AND A RADIAL FLANGE AT THE BOTTOM OF THE SKIRT, COMPRISING A SUPPORT, A CUTTING DIE ON SAID SUPPORT HAVING A FIXED CUTTING EDGE, A DRAW DIE FIXEDLY MOUNTED WITHIN SAID CUTTING DIE AND HAVING AN UPPER SURFACE, A CUTTING PUNCH MOUNTED ABOVE SAID CUTTING DIE FOR MOVEMENT TOWARD AND AWAY FROM SAID CUTTING DIE AND HAVING AN OUTER PERIPHERAL CUTTING EDGE ADAPTED TO COACT WITH SAID CUTTING EDGE OF THE CUTTING DIE TO SEVER A CLOSURE BLANK FROM SHEET MATERIAL OVERLYING SAID CUTTING DIE, A DRAW PUNCH MOVEMENT ABOVE SAID DRAW DIE FOR MOVEMENT TOWARD AND AWAY FROM SAID DRAW DIE, MEANS PROVIDING A SUBSTANTIALLY RADIALLY RIBBED DRAW SURFACE AROUND THE INNER PERIPHERY OF SAID DRAW DIE, MEANS ALSO PROVIDING AN UPWARDLY OPEN CIRCUMFERENTIAL DEPRESSION AROUND THE UPPER PART OF SAID DRAW SURFACE, MEANS FOR CLAMPING THE OUTER PERIPHERY OF THE SEVERED BLANK PRIOR TO DRAWING OF SAID BLANK, MEANS FOR MOVING SAID DRAW PUNCH TOWARD SAID DRAW DIE FOR FORMING SAID CLOSURE, AND MEANS PROVIDING A SERIES OF CIRCUMFERENTIALLY SPACED RADIAL PROJECTIONS ON SAID DRAW PUNCH CORRESPONDINGLY LOCATED RELATIVE TO SAID DEPRESSION, SO THAT WHEN SAID DRAW PUNCH DESCENDS AFTER THE BLANK HAS BEEN CUT THE DRAW PUNCH ENGAGES THE BLANK TO FORCE IT IN FORMING RELATION OVER SAID DRAW SURFACE WITH SAID RIBBED SURFACE FORMING CORRUGATIONS IN THE CLOSURE FLANGE AND SAID PROJECTIONS COOPERATING WITH SAID DEPRESSION FOR FORMING CIRCUMFERENTIALLY SPACED LUGS IN THE CLOSURE SKIRT.