Fire finding apparatus
US5751215A · kind A · utility
Inventor
Key dates
| Filing date | Nov 21, 1996 |
| Grant date | May 12, 1998 |
| Priority date | — |
| Expiry date | Nov 21, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B17/12
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
An infrared sensor is particularly well suited for the detection of heat sources, specifically from fires. It comprises an infrared detector receiving infrared radiation from a focused refractive optical unit. An optical chopper and electronic amplifier enable the sensor to operate without drift and with immunity to temperature changes in the sensor itself. The infrared radiation from the optical unit is appropriately filtered so as to optimize reception in a frequency band between 2.6 and 2.8 microns. In this band, there exists negligible energy from the sun due to absorption by gas molecules in the earth's atmosphere. Consequently, the sensor can be used in full sunlight without becoming saturated by the large magnitude infrared radiation of the sun. The sensor contains circuitry providing an audible output signal whose pitch is proportional to the intensity of the infrared radiation received from nearby heat sources. The device does not require any visual attention from a firefighter. The detector is housed in a cylindrical case appropriate for manipulation by a heavily gloved hand of the firefighter. A self-test feature operates briefly when the sensor is first turned on to ass…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.