| 摘要 |
A photoelectric smoke detector suitable for downsizing without reducing a detection power. The photoelectric smoke detector for detecting the presence of smoke by using a light emitting element and a light receiving element of which optical axes cross, characterized by comprising a labyrinth function-only exhibiting unit charged with only a labyrinth function that induces an air stream into an inner space thereof and prevents a disturbance light from advancing into the inner space, a smoke detecting unit that is provided above the labyrinth function-only exhibiting unit so as to allow its inner space to communicate with the inner space of the labyrinth function-only exhibiting unit, incorporates the light emitting element and the light receiving element, and has small holes through which an air stream passed through a detection area in the vicinity of the intersection between the optical axes of the light emitting element and the light receiving element is led out. |
