Emergency door opening device
US4129811A · kind A · utility
8Cited by
3References
1Claims
0Family size
Inventor
Key dates
| Filing date | Oct 25, 1977 |
| Grant date | Dec 12, 1978 |
| Priority date | — |
| Expiry date | Oct 25, 1997 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE05Y2900/40
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A relay system maintains an emergency door opening device circuit open so that a door of a structure remains closed as long as an electrically energized ventilation system of the structure is supplied with electrical energy from a commercial power source. When the power fails, the relay system closes the emergency door opening device circuit, which includes its own power source, to operate a door opening device which opens a door to the structure to provide emergency ventilation for the structure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.