Communications: electrical – Condition responsive indicating system – Specific condition
Patent
1996-11-21
1998-05-12
Hofsass, Jeffery
Communications: electrical
Condition responsive indicating system
Specific condition
340620, 340514, 340693, 374121, 374131, 374141, 374170, 219502, G08B 1700
Patent
active
057512159
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 assure the user that the sensor is fully operational. A "downed firefighter" feature sounds an alarm in the event that the firefighter becomes immobile.
REFERENCES:
patent: 3017513 (1962-01-01), Messelt
patent: 3555243 (1971-01-01), Roman
patent: 3597755 (1971-08-01), Parkin
patent: 3761713 (1973-09-01), Merrill
patent: 3943499 (1976-03-01), Dunphy
patent: 3993138 (1976-11-01), Stevens et al.
patent: 4494881 (1985-01-01), Everest
patent: 4634294 (1987-01-01), Christol et al.
patent: 5045839 (1991-09-01), Ellis et al.
patent: 5283549 (1994-02-01), Mehaffey et al.
patent: 5352039 (1994-10-01), Barral et al.
patent: 5422484 (1995-06-01), Brogi et al.
Fire Finder II, Model 955 Dyn-Optics Infrared heat sensor.
Hofsass Jeffery
Lee Benjamin C.
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