| 摘要 |
PURPOSE:To establish the sensing unit enabling to perform stable sensing operation test, by setting the position relation of the simulated scattering body to optical system block to always optimum state. CONSTITUTION:When the test push button is not depressed, the rotary shaft 16 is turned counterclockwise with the deflection force of the spring 20 to position the metal piece 17 between the light emitting element 13 and the shield light wall 15. Accordingly, with this condition, the effect of the metal piece 17 to the photo detection element 14 is avoided, and only to the smoke from the smoke inlet, the scattering of light transmitting in the smoke is detected with the photo detection element 14 and smoke sensing is made. Further, when the push button 19 is operated, if the drive piece 18 is depressed, the turn shaft 16 is turned clockwise to move the metal piece 17 on the light shield wall 15. Thus, the light from the light emitting element 13 reflects on the metal piece 17, this reflection light is detected at the photo detection element 14 to test the smoke sensing. |
