Shell for can ends
US4637961A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 22, 1985 |
| Grant date | Jan 20, 1987 |
| Priority date | — |
| Expiry date | Aug 22, 2005 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/12264
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
The disclosure relates to a novel shell such as used in the manufacture of can ends, and to a method and tools for making such a shell. A non-circular blank having rounded corners is cut from thin metal. The blank is oblong in a direction transverse to the grain of the metal. A first set of tools separates the blanks and forms a substantially flat central panel and an upward-extending chuck wall about the edge of the panel to produce a partially formed shell. The junction area between said panel and said chuck wall has a relatively large radius of curvature at this time. A second set of tools forms in the blank a lip extending outward from the upper end of the chuck wall and generally parallel to said panel; then the panel and the chuck wall are separately gripped, followed by relative movement between the panel and the chuck wall while wrapping the junction area around a forming punch to form a panel wall in said junction area extending upward from the inner part of said chuck wall. Then the lip is formed into a curl edge section which ends in an inner curl diameter that is round and concentric with the chuck wall, and has progressively lesser radii of curvature from upper end of …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.