Patent · US Expired

Method and apparatus for forming container end panels

US4808052A · kind A · utility

89Cited by
8References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 3, 1988
Grant dateFeb 28, 1989
Priority date
Expiry dateMar 3, 2008

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB21D51/44
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

A method of forming a container end piece from a sheet of material includes the steps of forming an inverted cup by wiping a peripheral edge of the material over a die core ring, inverting the cup by advancing a punch core into the material, thereby forming a flanged area, a central bottom area and a chuckwall interconnected thereto by a radiused portion. The radiused portion is initially formed by an annular nose on the punch core larger than the final radius. The punch core is then retracted and exerts force on the flanged area to shorten the chuckwall and reduce the radius by forcing the material in the chuckwall and radiused areas into the space between a die core and die core ring. A modified method includes supporting and aligning the radiused area with a contoured knockout sleeve between the die core and die core ring. The apparatus includes a punch core having a radiused annular nose which can be advanced into the inverted cup to form a reversed cup having a flanged area, a chuckwall and a central bottom area with the chuckwall interconnected to the central bottom area by a radiused portion conforming to the radius on the punch core. The apparatus further includes a die cor…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.