Supervisory control system for a smoke detector
US4266219A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 18, 1978 |
| Grant date | May 5, 1981 |
| Priority date | — |
| Expiry date | Sep 18, 1998 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B17/113
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
The present invention is particularly useful with an optical smoke detector system of the Tyndall type. The system includes a chamber, an emitter for periodic energization to provide radiation within the chamber, and a sensor for providing an electrical information signal related to the amplitude of radiation passing from the emitter. In the absence of particles of combustion, radiation impinges on the sensor at a reference level. When particles enter the chamber they are struck and diffuse the radiation from the emitter, raising the level of the signal produced by the sensor. The invention includes a supervisory arrangement for checking the normal pulse received by the sensor when no particles are in the chamber, thus checking the efficacy of the emitter and sensor as well as the chamber operation. When a filter and amplifier are connected to process the signal from the sensor, the supervisory circuit can be connected to the output side of the amplifier and thus also monitor the operability of these components. The system also supervises the adequacy of the energizing potential.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.