Flow sensor apparatus including a thin film sensor

摘要

The bridge-like thin film sensor 5 is frangible as thin and bridge-like form suspended over the hollow 3. In case that a pieces of dust hits it, it is often broken. In view of the foregoing drawbacks in the background flow sensor, one object of the present invention to provide a novel flow sensor which hard to break by a pieces of dust. In accordance with the present invention, this object of the present invention is attained by a novel flow sensor which includes a substrate installed in the fluid path; a hollow formed on a surface of the substrate; a thin film sensor portion suspended over the hollow; and a guard portion near of the hollow; wherein the width of seid sensor portion is formed being not destructed by a pieces pieces of dust having the about same width of said sensor portion when the pieces of dust collides with said sensor portion.