| 摘要 |
PURPOSE:To improve the detecting accuracy of smoke and to transmit the reduction of the accuracy to the external if necessary by providing the titled device with a heating means heating a transparent window for projecting or receiving light or a reflecting plate which is opposed to an exhaust path and a disconnection detecting means detecting the disconnection. CONSTITUTION:The smoke detector 32 consists of a light projecting/detecting part 33 projecting light to the path (exhaust path) in a discharge pipe 23 and detecting the projected light and a detecting part 34 generating the light projected from the light projecting/detecting part 33, receiving the light from the part 33 to output a smoke detecting signal SA corresponding to the detected quantity of light and also detecting the disconnection of the heating means to output a disconnection detecting signal SB. The disconnection of heaters 42, 47 is discriminated by reading the disconnection detecting signal SB from the smoke detector 32. Said constitution makes it possible to improve the detecting accuracy, and if the accuracy is reduced, to transmit the reduction to the external. |
