Flow rate measuring device and flow rate controller

摘要

A flow rate measuring device includes a fluid resistance member through which measurement target fluid flows; an upstream side pressure sensor configured to measure pressure on an upstream side of the fluid resistance member from a change of electrical resistance of a resistive element attached to a pressure sensitive surface onto which the target fluid is introduced, and also to measure a temperature of the pressure sensitive surface from a temperature-dependent change of the electrical resistance of the resistive element; a temperature sensor to measure a temperature of the target fluid flowing through the fluid resistance member; and a flow rate calculation part that calculates a flow rate of the target fluid based on the pressure measured by the upstream side pressure sensor, pressure-flow rate characteristics of the fluid resistance member, the upstream side pressure sensor temperature, and the target fluid temperature in the fluid resistance member.

主权项

1. A flow rate measuring device comprising:
a fluid resistance member through which target fluid to be measured flows; an upstream side pressure sensor in an upstream side flow path, the upstream side pressure sensor having a pressure sensitive surface onto which the target fluid on an upstream side in the fluid resistance member is introduced, the upstream side pressure sensor configured to measure a pressure of the target fluid from a change of an electrical resistance value of a resistive element that is provided so as to be deformed in conjunction with deformation of the pressure sensitive surface and to measure a temperature of the upstream side pressure sensor from a temperature-dependent change of the electrical resistance value of the resistive element; a temperature sensor that is arranged in a location where a temperature of the target fluid flowing through the fluid resistance member is measured; and a flow rate calculation part that calculates a flow rate of the target fluid on a basis of at least the pressure measured by the upstream side pressure sensor of the upstream side flow path, a pressure-flow rate characteristic of the fluid resistance member, the temperature of the upstream side pressure sensor measured by the upstream side pressure sensor, and a temperature of the target fluid in the fluid resistance member, the temperature of the target fluid being measured by the temperature sensor.