US 10,768,033 B2 · Thermal flowmeter

Abstract

The object of the invention is to obtain a thermal flowmeter which effectively causes water droplets to be directed to a discharge port when the water droplets adhered to a wall surface of a first passage are drawn into a third passage portion. A thermal flowmeter of the present invention includes a sub-passage that takes a measurement gas flowing through a main passage; and a flow detection unit that measures a flow rate of the measurement gas by performing heat transfer with the measurement gas flowing through a sub-passage. Further, the sub-passage includes a first passage, a second passage portion branching in the middle of the first passage portion to be directed toward the flow detection unit; and a third passage portion branching in the middle of the second passage portion to be directed toward a third outlet, and a pressure loss generation means is provided between a third inlet and the third outlet of the third passage portion.

Claims10

Dependent claims

A thermal flowmeter comprising:

a casing arranged in a main passage;
a sub-passage that takes a measurement gas flowing through the main passage into the casing;
and
a flow detection unit that measures a flow rate of the measurement gas in the sub-passage,
wherein the sub-passage includes:
a first passage portion communicating between a first inlet open to the casing and a first outlet open to the casing;
a second passage portion communicating between a second inlet open to the first passage portion and a second outlet open to the casing or the first passage portion;
and
a third passage portion communicating between a third inlet open to the second passage portion and a third outlet open to the casing, and
a pressure loss generation means is provided between the third inlet and the third outlet of the third passage portion.

7 more elements

Dependencies are inferred from the claim text.

Thermal flowmeter

Life of this patent

Thermal flowmeter

Life of this patent

Abstract

Claims10