| 摘要 |
PURPOSE:To detect the breaking of a light source, a decrease in the quantity of light, etc., by adjusting the brightness of dark box constituent materials of the smoke detector and internal surface paint for the dark box to optional values. CONSTITUTION:When the brightness of the dark box is adjusted, materials and paints which vary in brightness from low (black) gradually are prepared and a material or paint corresponding to a spacific noise light signal is determined, and a material or paint having brightness corresponding to it is only used. When only the wire breaking of a light emitting element is detected, a decision is made with a small quantity of the noise light signal, so a material or paint with low brightness is selected. When a decrease in the quantity of light of the light emitting element is detected, on the other hand, the level of an initial noise light signal needs to be set high, so a material or paint having relatively high brightness needs to be selected. Thus, the amount of the initial noise light signal is adjusted by selecting the material and paint for the dark box, thereby obtaining various fault signals. Further, the level variation of a fire signal accompanying variation in initial level is adjusted by varying the amplification factor of an amplifier. |
