Optical dust detector assembly for use in an automotive vehicle

An optical dust detector assembly adapted for use in an automotive vehicle for detecting the concentration of dust, smoke or the like contained in a flow of air passing therethrough, the detector assembly comprising:

• air duct means arranged parallel to said air flow and having an introductory portion with an inlet opening, a base portion with an outlet opening, and a pair of radial holes formed in a base portion in peripheral wall and opposed to each other;
• a pair of casings disposed at said base portion peripheral wall on both sides thereof and having respective openings ends communicating with the interior of said base portion through the respective radial holes thereof;
• a light emission element arranged within one of said casings to emit a light beam therefrom and pass it through the radial holes of said base portion toward the other casing;
• and
• a light receiving element arranged within the other casing to receive the light beam emitted from said light emission element and passed through the radial holes of said base portion;
• wherein said air duct member is bent in such a manner as to provide therein an inclined internal surface for deflecting upwardly the flow of air introduced through the introductory portion thereof, and wherein the radial holes are formed in the peripheral wall of the base portion of said duct member to face the flow of air after deflection by the inclined internal surface.