Alarm detector responsive to rate of change of a monitored condition
US4065758A · kind A · utility
10Cited by
5References
15Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 2, 1975 |
| Grant date | Dec 27, 1977 |
| Priority date | — |
| Expiry date | Jan 2, 1995 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B17/12
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A physical quantity such as temperature, infrared radiation or smoke is detected by means of a conversion device for emitting an alarm signal whose amplitude is representative of the intensity of the physical quantity. The detector comprises a unit for measuring relative variations of the signal in time, for comparing them with a preset threshold level and for actuating the alarm when they exceed the threshold level.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.