Die assembly

Claim 1

AN APPARATUS OF THE CHARACTER DESCRIBED FOR FORMING ING SHEET MATERIAL FOR USE WITH A PRESS HAVING A RAM AND BED INCLUDING, A PUNCH SHOE SECURED TO THE RAM FOR MOVEMENT THEREWITH TOWARD AND AWAY FROM SAID BED, AN UPPER PUNCH ENGAGED WITH AND CAPABLE OF MOVEMENT RELATIVE TO SAID SHOE, SAID UPPER PUNCH HAVING A PRESSURE SURFACE FOR GRIPPING THE MATERIAL, AN UPPER CURL RING MOUNTED ON SAID PUNCH SHOE AND CIRCUMSCRIBING SAID PUNCH, SAID CURL RING HAVING A PRESSURE SURFACE FOR GRIPPING THE MATERIAL, A DIE BASE MOUNTED ON SAID BED AND HAVING A LOWER PUNCH ADAPTED FOR COOPERATING WITH SAID UPPER PUNCH TO FORM THE MATERIAL THEREBETWEEN, AN INNER DRAW RING CIRCUMSCRIBING THE LOWER PUNCH AND ADAPTED FOR LIMITED VERTICAL MOVEMENT RELATIVE THERETO, SAID DRAW RING HAVING A FIRST PRESSURE SURFACE ADAPTED TO COOPERATE WITH THE PRESSURE SURFACE ON SAID UPPER PUNCH FOR GRIPPING THE MATERIAL THEREBETWEEN BEFORE, AND DURING THE FORMING OPERATION AND HAVING A SECOND PRESSURE SURFACE ADAPTED TO COOPERATE WITH THE PRESSURE SURFACE ON SAID UPPER CURL RING FOR GRIPPING THE MATERIAL THEREBETWEEN AFTER THE FORMING OPERATION, A FIRST SLIDE ASSOCIATED WITH SAID UPPER PUNCH AND CAPABLE OF LIMITED MOVEMENT RELATIVE TO SAID RAM, SAID FIRST SLIDE ADAPTED TO SELECTIVELY TRANSMIT DOWNWARD FORCE TO SAID UPPER PUNCH, A CHAMBER COMMUNICATING WITH SAID FIRST SLIDE, MEANS FOR DELIVERING SUBSTANTIALLY CONSTANT AIR PRESSURE INTO SAID CHAMBER WHEREBY A FORCE IS TRANSMITTED TO THE UPPER PUNCH THROUGH SAID FIRST SLIDE EFFECTIVELY PARALLEL TO THE DIRECTION OF MOVEMENT THEREOF AS THE RAM MOVES TOWARD THE BED, SAID MOVEMENT EFFECTING THE INITIAL FORMING OF THE MATERIAL BETWEEN THE UPPER AND LOWER PUNCHES, SAID PRESSURE SURFACES ON SAID DRAW RING AND UPPER PUNCH POSITIVELY GRIPPING THE MATERIAL BEFORE AND DURING THE INITIAL FORMING THEREOF AS THE DRAW RING IS URGED BY THE UPPER PUNCH TO MOVE RELATIVE TO THE LOWER PUNCH, AND MEANS FOR MAINTAINING THE POSITIVE GRIPPING OF THE MATERIAL BETWEEN THE SECOND PRESSURE SURFACE ON SAID DRAW RING AND THE PRESSURE SURFACE ON SAID UPPER CURL RING DURING THE FINAL FORMING STAGE, SAID MEANS INCLUDING A SECOND SLIDE ADAPTED FOR LIMITED MOVEMENT RELATIVE TO THE FIRST SLIDE AND CAPABLE OF SELECTIVELY SUPPORTING SAME, AN AIR SPACE COMMUNICATING WITH SAID SECOND SLIDE, MEANS FOR INTRODUCING INCREASING AIR PRESSURE INTO SAID SPACE TO EXERT FORCE ON THE SECOND SLIDE AS THE RAM NEARS THE BOTTOM OF ITS STROK, WHEREBY THE MAGNITUDE OF THE FORCE ON SAID SECOND SLIDE IS GREATER THAN AND OPPOSED TO THE FORCE ON SAID UPPER PUNCH THEREBY SEPARATING SAID UPPER PUNCH AND SAID LOWER PUNCH WHILE MAINTAINING THE POSITIVE GRIPPING OF THE MATERIAL BETWEEN SAID PRESSURE SURFACES DURING THE FINAL FORMING THEREOF AS THE RAM WITHDRAWS, WHEREBY THE MATERIAL IS PROTECTED FROM DAMAGE OR WRINKLING DUE TO EXCESSIVE FORCE.

Claim 2

AN APPARATUS OF THE CHARACTER DESCRIBED FOR FORMING ING SHEET MATERIAL FOR USE WITH A PRESS HAVING A RAM AND BED INCLUDING, A PUNCH SHOE SECURED TO THE RAM FOR MOVEMENT THEREWITH TOWARD AND AWAY FROM SAID BED, AN UPPER PUNCH ENGAGED WITH AND CAPABLE OF MOVEMENT RELATIVE TO SAID SHOE, SAID UPPER PUNCH HAVING A PRESSURE SURFACE FOR GRIPPING THE MATERIAL, AN UPPER CURL RING MOUNTED ON SAID PUNCH SHOE AND CIRCUMSCRIBING SAID PUNCH, SAID CURL RING HAVING A PRESSURE SURFACE FOR GRIPPING THE MATERIAL, A DIE BASE MOUNTED ON SAID BED AND HAVING A LOWER PUNCH ADAPTED FOR COOPERATING WITH SAID UPPER PUNCH TO FORM THE MATERIAL THEREBETWEEN, AN INNER DRAW RING CIRCUMSCRIBING THE LOWER PUNCH AND ADAPTED FOR LIMITED VERTICAL MOVEMENT RELATIVE THERETO, SAID DRAW RING HAVING A FIRST PRESSURE SURFACE ADAPTED TO COOPERATE WITH THE PRESSURE SURFACE ON SAID UPPER PUNCH FOR GRIPPING THE MATERIAL THEREBETWEEN BEFORE, AND DURING THE FORMING OPERATION AND HAVING A SECOND PRESSURE SURFACE ADAPTED TO COOPERATE WITH THE PRESSURE SURFACE ON SAID UPPER CURL RING FOR GRIPPING THE MATERIAL THEREBETWEEN AFTER THE FORMING OPERATION, A FIRST SLIDE ASSOCIATED WITH SAID UPPER PUNCH AND CAPABLE OF LIMITED MOVEMENT RELATIVE TO SAID RAM, SAID FIRST SLIDE ADAPTED TO SELECTIVELY TRANSMIT DOWNWARD FORCE TO SAID UPPER PUNCH, A CHAMBER COMMUNICATING WITH SAID FIRST SLIDE, MEANS FOR DELIVERING SUBSTANTIALLY CONSTANT AIR PRESSURE INTO SAID CHAMBER WHEREBY A FORCE IS TRANSMITTED TO THE UPPER PUNCH THROUGH SAID FIRST SLIDE EFFECTIVELY PARALLEL TO THE DIRECTION OF MOVEMENT THEREOF AS THE RAM MOVES TOWARD THE BED, SAID MOVEMENT EFFECTING THE INITIAL FORMING OF THE MATERIAL BETWEEN THE UPPER AND LOWER PUNCHES, SAID PRESSURE SURFACES ON SAID DRAW RING AND UPPER PUNCH POSITIVELY GRIPPING THE MATERIAL BEFORE AND DURING THE INITIAL FORMING THEREOF AS THE DRAW RING IS URGED BY THE UPPER PUNCH TO MOVE RELATIVE TO THE LOWER PUNCH, AND MEANS FOR MAINTAINING THE POSITIVE GRIPPING OF THE MATERIAL BETWEEN THE SECOND PRESSURE SURFACE ON SAID DRAW RING AND THE PRESSURE SURFACE ON SAID UPPER CURL RING DURING THE FINAL FORMING STAGE, SAID MEANS INCLUDING A SECOND SLIDE ADAPTED FOR LIMITED MOVEMENT RELATIVE TO THE FIRST SLIDE AND CAPABLE OF SELECTIVELY SUPPORTING SAME, AN AIR SPACE COMMUNICATING WITH SAID SECOND SLIDE, MEANS FOR INTRODUCING INCREASING AIR PRESSURE INTO SAID SPACE TO EXERT FORCE ON THE SECOND SLIDE AS THE RAM NEARS THE BOTTOM OF ITS STROK, WHEREBY THE MAGNITUDE OF THE FORCE ON SAID SECOND SLIDE IS GREATER THAN AND OPPOSED TO THE FORCE ON SAID UPPER PUNCH THEREBY SEPARATING SAID UPPER PUNCH AND SAID LOWER PUNCH WHILE MAINTAINING THE POSITIVE GRIPPING OF THE MATERIAL BETWEEN SAID PRESSURE SURFACES DURING THE FINAL FORMING THEREOF AS THE RAM WITHDRAWS, WHEREBY THE MATERIAL IS PROTECTED FROM DAMAGE OR WRINKLING DUE TO EXCESSIVE FORCE.