Patent References 3122638 3739365 3761715 3825754 Dual spectrum infrared fire detector Two channel optical flame detector Optical flame and explosion detection system and method Flame detector Dual spectrum infrared fire sensor Fire sensor cross-correlator circuit and method InventorsAssigneeApplicationNo. 058662 filed on 04/10/1998US Classes:250/339.15, Sensing flame or explosion250/342Locating infrared emissive objectsExaminersPrimary: Ham, SeungsookAssistant: Patti, John Foreign Patent References
International ClassG01J 005/02AbstractA flame detector consisting of a first infrared radiation detector for detecting radiation from combustion of hydrocarbon and other carbon containing compounds in conjunction with a second infrared radiation detector for distinguishing radiation from other sources such as modulated sunlight, reflections, artificial as well as natural hot objects, illuminating light sources, and arc welders. The flame detector uses two electronic circuits following the first infrared detector such that a fire is sensed by either of the two circuits depending on its size, one circuit being optimized for flicker frequencies present in a large fire while the second circuit simultaneously checks for optical signals at flicker frequencies dominant in a smaller fire. The two electronic outputs along with the output of the second infrared detector are digitally processed and analyzed for spectral and temporal characteristics to distinguish the presence of a real fire from that of various false alarm sources. The flame detector is provided with digital serial communications so as to output its status, permit changes in the programming of operating parameters and modes and permit troubleshooting via remote control.Field of SearchSensing flame or explosionDetecting infrared emissive objects Locating infrared emissive objects PHOTOMETERS Detector and indicator electrical coupling (e.g., amplifying or attenuating) MEASURING MICROSCOPES (GO1B 9/04) Radiation pyrometer Thermal CONDITION RESPONSIVE INDICATING SYSTEM With particular system function (e.g., temperature compensation, calibration) | |