Punch pin head structure
US4700601A · kind A · utility
13Cited by
4References
1Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Apr 28, 1986 |
| Grant date | Oct 20, 1987 |
| Priority date | — |
| Expiry date | Apr 28, 2006 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T83/943
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
Punches for paper and the like have a metal pin having a male punch element formed on one end and a pressure application area on the opposite end. To withdraw the punch pin an enlargement is formed at or near the opposite end, the enlargement cooperating with a gripper or a spring in the punch to cause the pin to retract when the pressure applicator retracts. In accordance with the present invention a circumferential groove is formed in the punch pin and a collar of plastic material is formed around the pin protruding into said groove and functioning as the enlargement.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.