Revolving security door
US4295297A · kind A · utility
15Cited by
3References
3Claims
0Family size
Inventors
Key dates
| Filing date | Sep 24, 1979 |
| Grant date | Oct 20, 1981 |
| Priority date | — |
| Expiry date | Sep 24, 1999 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE05Y2900/132
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
Security door including a revolving door with a one way bearing continuously preventing rotation of the door in a reverse direction so that persons can only travel from an entry to an exit side of the door by passing around the door axis in a forward direction. A mat switch is positioned so that persons attempting to pass from the exit side to the entry side by revolving the door in the forward direction must stand on the mat switch and operate it. Operation of the mat switch causes operation of a clutch which locks the door against rotation in the forward direction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.