HEAT-SENSING ELEMENT OF FIRE ALARM Russian patent published in 2001 - IPC

FIELD: electric fire alarms. SUBSTANCE: heat-sensing element used for fire alarms to detect temperature distribution over zone of fire and to automatically turn on fire alarm systems is, essentially, thermopile built up of two thermocouples formed by four conductors and characterized in ability of contrast discrimination of signal component in frequency band of 2-3 Hz. Novelty is that materials, shape, and size of two internal conductors of thermopile are chosen so as to ensure definite relation between coefficients of thermal electromotive force and time constants of thermocouple junctions. EFFECT: enhanced noise immunity of information reliability of fire detection. 4 dwg