Fire alarm device

A fire alarm device for judging an outbreak of a fire and emitting an alarm, comprising:

• detection means for detecting at least one physical quantity of physical quantities in form of temperature, smoke density and gas arising from the outbreak of the fire;
• arising quantity calculating means for calculating heat release quantity smoke generation quantity, gas generation quantity and the like per unit time based on detection data transferred from said detection means;
• membership functions table means for storing coefficients providing predetermined correlation between arising value per unit time, such as heat release quantity, smoke generation quantity and gas generation quantity and the danger degree which a person would feel with respect to said arising value;
• danger degree calculating means for calculating the danger degree corresponding to the heat release quantity, the smoke generation quantity, gas generation quantity and the like calculated by said arising quantity calculating means based on said membership functions table means;
• and
• judging means for determining the kind of an alarm to be emitted depending upon said danger degree calculated by said danger degree calculating means;
• environment coefficient table means for storing coefficients providing environmental conditions such as size of a room and whether or not easy-burning materials are present, said danger degree calculating means calculating the danger degree based on said membership functions table means and the environment coefficient table means;
• said detection means comprising a plurality of different detectors;
• sampling means between said detectors and said arising quantity calculating means for scanning sequentially values from said different detectors and transmitting said values to said arising quantity calculating means;
• said judging means including output pre-alarm means, output fire alarm means and output fire prevention devices control signal actuated in dependence on the danger degree calculated by said danger degree calculating means.