Patent ID: 6470742
Filing Date: 2002-10-29
Classification: G01P

Abstract:
A flow sensor for measuring the flow rate of a fluid flowing over a flow detection element by supplying power to a heating element, the flow detection element comprising:a diaphragm formed by removing part of a substrate; a heating element made of a heat sensitive resistor film and formed on the diaphragm; electrode portions for the heating element formed on the substrate; lead patterns extending from the electrode portions to a portion near the diaphragm; and connection patterns, at least part of which are formed on the diaphragm, for connecting the lead patterns to a patter of the heating element, wherein additional patterns are formed on the diaphragm or the diaphragm and a portion therearound so that a tin film pattern including the additional patterns formed on the diaphragm become substantially symmetrical on the diaphragm with respect to a center axis in a longitudinal direction and a transverse direction of the diaphragm.