Smoke detector with bimetallic element for temperature compensation
US4241282A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 16, 1978 |
| Grant date | Dec 23, 1980 |
| Priority date | — |
| Expiry date | Oct 16, 1998 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B17/113
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A smoke detector having a radiation source operating in the infrared, visible or ultraviolet wavelength region, transmitting radiation throughout an expanded or extended solid angle region of predetermined minimal extent. A radiation receiver is arranged externally of this radiation region for the reception of radiation which has been scattered at smoke particles and for signal transmission upon exceeding a predetermined smoke density. To compensate for decrease in smoke sensitivity of the smoke detector with temperature increase there is provided a bimetallic strip which, in the presence of a temperature increase, gradually moves into a small part of the radiation region and causes an additional irradiation of the radiation receiver. By suitable selection and arrangement of the bimetallic element the smoke sensitivity remains almost constant up to a predetermined critical temperature, or the smoke sensitivity gradually increases with increasing temperature.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.