Photoelectricity type smoke sensor and smoke detecting section atsusenburii

摘要

A photoelectric smoke detector includes a smoke detecting section defining a smoke detecting space, a light emission section holder having a light-emission element disposed in the smoke detecting section and a light receiving section holder having a light-receiving element disposed in the smoke detecting section. The light-receiving element receives light which has been emitted from the light-emission element and is scattered by smoke flowing in the smoke detecting space. A hybrid circuit board has an integrated circuit mounted thereon and is housed in the light receiving section holder. The integrated circuit including the light-receiving element and at least a received-light signal amplifying circuit. The hybrid circuit board is arranged so that the light-receiving surface of the light-receiving element is directed toward the smoke detecting space.