Die assembly for and method of forming metal end unit.

摘要

This relates to special tooling (10-26) for forming metal end units for use in conjunction with cans for carbonated beverages and the like wherein the formed end unit is provided with an integral reinforcement in the form of a countersink (56) so as to increase the buckle strength of such an end unit when it is formed of thin metal. Previously there has been developed tooling for forming such an end unit which, while it is commercially satisfactory, did not produce end units having the required buckle resistance. That tooling has been modified by changing the configuration of a punch core (10) so as to eliminate a previously formed cylindrical extension of the end unit chuck wall and a countersink starter. The punch core (10) cooperates with a die core (26) to clamp a center panel of a formed end unit shell (60) so as to move the center panel reversely of its forming direction and to effect a folding of an outer peripheral portion (50) of the center panel in a lower part of the previously formed chuck wall into the required countersink.