Smoke detector
US4175865A · kind A · utility
21Cited by
8References
23Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 14, 1977 |
| Grant date | Nov 27, 1979 |
| Priority date | — |
| Expiry date | Mar 14, 1997 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B17/113
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
An optical smoke detector comprising a radiation source transmitting radiation throughout a predetermined spatial region and at least one radiation receiver to which there is delivered the radiation scattered by particles located in the radiation region. One or a number of elements conducting radiation by reflection are provided and arranged such that they remove radiation, which has been forwardly scattered at an acute angle with respect to the radiation direction, at a substantially ring-shaped zone about the region of direct radiation and delivers such removed forwardly scattered radiation to the radiation receiver.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.