Mass flow sensor, mass flow meter including the mass flow sensor, and mass flow controller including the mass flow sensor

摘要

In order to provide a mass flow sensor with reduced zero point fluctuation, a mass flow meter including the mass flow sensor, and a mass flow controller including the mass flow sensor, the mass flow sensor 20 according to the present invention is configured such that the fluid has an end (first end). Part 21) to the other end (second end 22) and two straight portions (straight portions) connecting the bottom and the bottom to the end (first end 21, second end 22) 22B, a linear pipe 22A having a linear portion 22A), a first thermal resistor 24 wound around one of the linear portions (the linear portion 22B or the linear portion 22A), A linear portion (the linear portion 22B or the linear portion) which is provided to be separated from the thermal resistor 24 near the end (the second end 22 or the first end 21) and around which the first thermal resistor 24 is wound. 22A) and the second thermal resistor 25 wound around Comprising a heat radiating portion 26 that is provided so as to contact on the second thermosensitive resistor 25 opposite to become the side of the duct pipe 23 across the first thermosensitive resistor 24.