Security screw
US4171662A · kind A · utility
28Cited by
3References
5Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 11, 1977 |
| Grant date | Oct 23, 1979 |
| Priority date | — |
| Expiry date | Aug 11, 1997 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S411/919
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A screw having its head shaped to prevent its removal by unauthorized persons, characterized in that it has peripherally thereof an odd number of sides arranged symmetrically with respect to the center of the head and inclined to the axis of the screw to prevent removal of the screw by the use of pliers. The screw is removed by the use of a matching socket wrench.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.