Patent ID: 6247495
Filing Date: 2001-06-19
Classification: G01F,Y10T

Abstract:
A flow rate detection mechanism comprising:a housing having a conduit for gas flow;a hollow holder inserted in the conduit wherein the holder has an annular groove on an outer surface of the holder, the holder has a through hole connecting the annular groove with an inner surface of the holder, and a portion of the gas flowing into the holder flows into the through hole;a resisting member inserted in the holder downstream of the through hole wherein a plurality of grooves are provided in an outer surface of the resisting member, the resisting member is held in place by elastic fasteners, each of which has a C-letter cross section and is inserted into one of the plurality of grooves by elastic deformation;a bypass passage formed between the outer surface of the resisting member and the inner surface of the holder, the housing further having a gas introducing hole connected at one end to a space defined between the conduit and the annular groove and a gas discharging hole connected at one end to a portion of the conduit downstream of the holder; anda sensor passage tube connecting the gas introducing hole with the gas discharging hole wherein a cross sectional area of an inner surface of the sensor passage tube is smaller than a cross sectional area of the gas introducing hole and the gas discharging hole.