Smoke detector of the ionization type
US4455553A · kind A · utility
47Cited by
3References
7Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | May 17, 1982 |
| Grant date | Jun 19, 1984 |
| Priority date | — |
| Expiry date | May 17, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B17/11
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
An ionization type smoke detector (10) includes a chamber having a measuring electrode (12), the voltage on the measuring electrode being a function of the concentration of smoke in the chamber, and further includes a comparison device (A3) for comparing the voltage measured on electrode (12) at two different times, and an output device (K) for producing an output signal if the voltages differ by a predetermined value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.