| 摘要 |
PURPOSE: To smoothly introduce smoke to a detection space and prevent the delay of the detection of smoke in a photoelectric smoke sensor. CONSTITUTION: The sensor has a first throttle part 29 immediately before a photodetecting element and a second throttle part 30 separated ahead of the first throttle part 29. A photodetecting part cover member 26 has a smoke introduction part 31 between the first throttle part 29 and the second throttle part 30 for introducing smoke from between labyrinth members to the second throttle part 30. |
