Patent ID: 9283611
Filing Date: 2016-03-15
CPC Classification: B21D

Claim Text:
1. A drawing die for deep drawing blanks which are punched out of sheet metal that is painted or coated with film material into flangeless moulded blanks comprising a drawing bell, a drawing core, a blank holder and a pneumatic spring which applies a spring force to the blank holder, wherein the pneumatic spring is formed by a gas volume in a chamber ( 30 ), which is sealingly closed by a piston ( 28 ), wherein the piston bears against the blank holder ( 22 ) by way of force transmission elements ( 24 ), and a venting valve ( 38 ) is associated to the chamber ( 30 ), wherein the venting valve ( 38 ) is actuated when the piston ( 28 ) arrives in a predetermined position, whereby the chamber ( 30 ) is suddenly vented.