Patent ID: 9026383
Filing Date: 2015-05-05
Classification: G01F

Abstract:
1. A flow rate sensor wherein two resistive elements whose resistance values change in accordance with a temperature of a fluid are arranged in an upstream side and a downstream side in a channel where the fluid flows, and two constant temperature control circuits each of which contains these resistive elements respectively are arranged so that a temperature of the resistive elements is controlled at a constant by the constant temperature control circuits, the flow rate sensor comprising: a flow rate calculation part that calculates a flow rate (Q) of the fluid based on an expression (Expression 2) using X the flow rate calculation part corrects a zero point output as being an output when the flow rate (Q) is zero by using a zero offset function (OFS) defined as a function of V where (OFS) is the zero offset function, and (SENSx) is a conversion function that converts a calculation value of an output from each constant temperature control circuit into a flow rate.