MODULATION FIRE DETECTOR Russian patent published in 2008 - IPC G08B17/12 

FIELD: fire engineering.

SUBSTANCE: modulation fire detector contains optical system and modulator made in the form of fixed reticle grating and movable reticle grating mechanically connected to electromechanical oscillator, every of reticle gratings of modulator having two zones of modulation of optical signals with identical constant periods. Optical system contains source of optical test signal and is arranged so that two signals are available at its outlet: test signal and signal of controlled space, which are separated in space and not mixed. Amplitude of the first pulse corresponds to the test signal, and that of the second pulse to signal of controlled space. Reticle gratings at the inlet of photodetector, only one optical signal may be available, either test signal one or that of controlled space.

EFFECT: increased fast action of device; validity of fire detection and reduction of consumed power and dimensions.

2 cl, 6 dwg