HIGH-SPEED FORMING OF CONTAINER SHELLS

摘要

Container shells (10) are formed by blanking a disc from a flat sheet, gripping a peripheral portion of the disc between annular end surfaces of a blank punch (28) and a draw pad (36), and supporting a central portion of the disc on a panel punch (40). The disc is engaged with a nose portion (66) of a punch die (32) near the peripheral edge of the panel punch and gripped between annular end surfaces of a knockout (30) and a crown ring (38) near the peripheral portion. The blank punch and the draw pad are axially moved to wipe the peripheral portion over an outer surface (98) of the crown ring to form a peripheral lip (20) of the shell. The punch die and the panel punch are axially moved to form the disc over an inner surface (94) of the crown ring to form a chuck wall (16) with an excess length of material. The panel punch is axially moved toward the punch die to roll the excess length of material along the nose portion and into a recess (64) of the punch die to form a countersink (14) and a central panel (12) of the shell without substantially changing a thickness of the material.