Method of detecting fire in an early stage
US5005003A · kind A · utility
12Cited by
12References
25Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 29, 1989 |
| Grant date | Apr 2, 1991 |
| Priority date | — |
| Expiry date | Mar 29, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B17/113
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
To improve probability of detection in the early stages of fires, a fire alarm (1) with a temperature sensor (3) is proposed, having a structural member (12) that causes the sensor (3) to react only to temperature changes in the ambient air, and which change with a frequency of from 0.1 to 20 Hz. The fire alarm (1) becomes particularly insensitive to errors when there is a second fire sensor (7) that reacts to fire aerosol, there being a threshold value circuit (9) that lowers the threshold value for the fire aerosol sensor (7) when the temperature sensor (3) exceeds a preset threshold value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.