FLOW RATE SENSOR

摘要

PROBLEM TO BE SOLVED: To provide a flow rate sensor which enables to accurate measure the flow rate of a viscous fluid in piping under wider environmental temperature conditions by minimizing the dependence on temperature of measured values of the flow rate. SOLUTION: This flow rate sensor is provided with a fluid passage pipeline 4 and a heat transfer fin plate 14 for detecting a flow rate so arranged to be affected by heat generated while being extended into the fluid passage pipeline 4 at a flow rate detection part in a flow rate detection unit 51. The sensing of temperature is executed being affected by heat absorbed by a fluid to be detected through the fin plate 14 based on the heat generated at the flow detection part to detect the flow rate of the fluid to be detected in the fluid passage pipeline 4 based on the results of the sensing of temperature. The fluid passage pipeline 4 has a fluid inflow side part 4b and a fluid outflow side part 4c and a central part 4a positioned therebetween along the direction of passage of the fluid to be detected and the fin plate 14 is extended into the fluid passage pipeline 4 at the central part 4a. The inner diameter of the central part 4a is smaller than that of the fluid inflow side part 4b.