Ionization type smoke sensor
US4017733A · kind A · utility
8Cited by
2References
7Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 17, 1975 |
| Grant date | Apr 12, 1977 |
| Priority date | — |
| Expiry date | Apr 17, 1995 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/66
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In a smoke sensor of the ionization type having as essential component parts an opposing pair of electrodes providing for high impedance effected by ionic current produced by a radioactive ray source, improvements are made to eliminate formation of dew at least on the surface of the radioactive ray source and also prevent the high impedance from being accidentally changed due to a cause other than smoke, for instance a comparatively intense air stream which may otherwise cause a casual change of the high impedance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.