Single station, in-die curling of can end closures
US4574608A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 4, 1985 |
| Grant date | Mar 11, 1986 |
| Priority date | — |
| Expiry date | Feb 4, 2005 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB21D51/44
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
Method and apparatus for forming end closures for containers complete with a peripheral curl for attachment to the top of a container without press modification includes a unique split die core ring. The method includes performing the operations of blanking the end panel against the cut edge, forming the chuckwall against the die core ring with a punch and punch shell and finally setting the chuckwall by wiping over the radius of the die core ring against a fluidly supported piston and simultaneously applying a curl to the peripheral edge of the panel prior to completion and removal from the press station. The method is performed by utilization of a split die core ring having inner and outer concentric segments, the outer segment of which is withdrawn as the punch shell advances to initiate a curl between the inner face of the punch shell and the outer face of the fixed inner segment of the die core ring. The apparatus for carrying out the method includes a conventional double acting press with a punch core on the inner slide, a punch shell on the outer slide and a die core on the fixed base. A split die core ring is employed on the fixed base and comprises a fixed inner ring and m…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.