Pressure flow meter and fluid control device

Abstract

The present invention provides a pressure-type flow meter and a fluid control device, the pressure-type flow meter comprising: a fluid resistance element (FR) provided in a flow path (L) through which a fluid flows, the fluid resistance element (FR) having a resistance flow path (RL) formed therein, the resistance flow path (RL) communicating with the flow path (L); an upstream-side pressure sensor (PS1) that detects the upstream-side pressure of the fluid resistance element (FR); and a downstream-side pressure sensor (PS2) that detects the downstream-side pressure of the fluid resistance element (FR), the fluid resistance element (FR) is sandwiched and fixed by a pair of sandwiching members (41, 42), sheet-like sealing members (51, 52) are provided between the fluid resistance element (FR) and the sandwiching members (41, 42), and protrusions (61, 62) that partially press the sealing members (51, 52) are formed on at least one of the fluid resistance element (FR) and the sandwiching members (41, 42).

Description

technical field [0001] The present invention relates to pressure flow meters and fluid control devices. Background technique [0002] As shown in Patent Document 1, in a flow control device (mass flow controller) using a conventional pressure type flowmeter, an element formed by laminating a plurality of thin plates is used as a fluid resistance element provided in a flow path. The fluid resistance element is clamped and fixed by a pair of clamping members from its lamination direction. [0003] Here, in order to prevent fluid leakage, a sheet-shaped sealing member (for example, a thickness of 500 μm or less) is provided between each of the pair of holding members and the fluid resistance element. Furthermore, the sheet-shaped sealing member is pressed by the planar opposing surfaces of the holding member and the fluid resistance element to seal between them. [0004] However, due to the thickness tolerance of the sheet-shaped sealing member or the tolerance of the fluid r...

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Problems solved by technology

[0004] However, due to the thickness tolerance of the sheet-shaped sealing member or the tolerance of the fluid resistance element or the block, there are cases where the sealing member cannot be sufficiently pressed, and thus the desired sealing performance cannot be obtained.

In addition, in order to improve the sealing performance, it is conceivable to increase the force of pressing the sheet-shaped sealing member, but if this is done, the fluid resistance element will be deformed, resulting in changes in the flow characteristics of the fluid resistance element

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