Pressure sensor, in particular for pressures of more than 100 bar

Patent metadata

Field	Value
Publication number	US-2025027828-A1
Application number	US-202218684699-A
Country	US
Kind code	A1
Filing date	Jul 22, 2022
Priority date	Aug 27, 2021
Publication date	Jan 23, 2025
Grant date	—

Abstract

A pressure sensor for measuring high pressures includes: a housing having a sealed volume filled with a compressible fill liquid, wherein the housing includes an elastically deflectable diaphragm having a rear side facing the filled volume and a front side opposite the rear side such that the diaphragm transmits a pressure applied to the front side of the diaphragm to the fill liquid; and a measuring unit adapted to ascertain a variable dependent on velocity of sound in the fill liquid and, based on the measured variable, to determine a pressure measured value representing the pressure on the front side of the diaphragm, wherein the fill liquid contains an organic compound, which is present in the fill liquid at a volume fraction of greater than 99%.

First claim

1 - 14 . (canceled)

15 . A pressure sensor, comprising:
a housing, which includes a sealed volume filled with a compressible fill liquid, wherein the housing includes an elastically deflectable diaphragm, which has a rear side facing the volume filled with the fill liquid and a front side opposite the rear side, the diaphragm operable to transmit a pressure applied to the front side of the diaphragm to the fill liquid; and a measuring unit configured to ascertain a variable dependent on a velocity of sound in the fill liquid and, based on the measured variable, to determine a measured pressure value representing the pressure applied to the front side of the diaphragm, wherein the fill liquid comprises an organic compound, which is present in the fill liquid at a volume fraction of greater than 99%.

16 . The pressure sensor according to claim 15 , wherein the organic compound is a nonpolar compound.

17 . The pressure sensor according to claim 15 , wherein the organic compound is in the liquid state in an intended pressure measuring range of the pressure sensor at least in a temperature range between 0° C. and 50° C.

18 . The pressure sensor according to claim 15 , wherein the organic compound is a saturated alcohol, an ester, an ether, or an aliphatic hydrocarbon.

19 . The pressure sensor according to claim 15 , wherein the organic compound is thermally stable at least up to a temperature of 100° C.

20 . The pressure sensor according to claim 15 , wherein the measuring unit comprises:
at least one ultrasonic transducer, which is arranged on or in a wall of the housing and configured to transmit and/or receive ultrasonic waves propagating along a measurement path; and a measuring circuit configured to excite the at least one ultrasonic transducer as to transmit ultrasonic waves and/or to receive and to process output signals of the at least one ultrasonic transducer as to ascertain a value of the variable dependent on the velocity of sound of the ultrasonic waves in the fill liquid.

21 . The pressure sensor according to claim 20 , wherein:
the housing includes the measuring unit and a diaphragm unit; the volume filled with the fill liquid includes a measuring chamber, a capillary tube, and a pressure chamber, each formed in the diaphragm unit and sealed by the diaphragm; the measuring chamber and the pressure chamber communicate with each other via the capillary tube; and the measurement path extends through the measuring chamber.

22 . The pressure sensor according to claim 20 , wherein the measuring circuit is further configured to determine the measured pressure value from the ascertained value of the variable dependent on the velocity of sound.

23 . The pressure sensor according to claim 22 , further comprising a temperature detector, which is operable to generate an electrical measurement signal dependent on a temperature of the fill liquid.

24 . The pressure sensor according to claim 23 , wherein the measuring circuit is configured to use measurement signals of the temperature detector for temperature compensation when determining the measured pressure value.

25 . The pressure sensor according to claim 15 , wherein the variable dependent on velocity of sound in the fill liquid is a travel time of an ultrasound pulse along the measurement path.

26 . The pressure sensor according to claim 15 , wherein the variable dependent on velocity of sound in the fill liquid is a resonant frequency, or another variable dependent on a resonant frequency, at which a standing wave forms along the measurement path.

27 . The pressure sensor according to claim 15 , wherein a wall of the housing surrounding the measuring chamber has a thickness of at least 2 mm.

28 . The pressure sensor according to claim 27 , wherein the thickness of the wall of the housing surrounding the measuring chamber is 2 to 6 mm.

29 . The pressure sensor according to claim 15 , wherein the elastically deflectable diaphragm is composed of a metal alloy.

30 . The pressure sensor according to claim 30 , wherein the metal alloy comprises at least one of a stainless steel, a duplex steel, tantalum, titanium, silver, brass, or bronze.

31 . The pressure sensor according to claim 15 , wherein the pressure sensor is configured to be operable at measured pressures greater than 100 bar.

32 . The pressure sensor according to claim 15 , wherein the pressure sensor is configured to be operable at measured pressures of at least 2000 bar.

33 . The pressure sensor according to claim 15 , wherein the measuring circuit includes measuring electronics.

Assignees

• Endress Hauser Se Co Kg

Inventors

• Lopatin Sergey
• Getman Igor
• Schleiferböck Jan
• Girardey Romuald
• Leuthner Dietmar
• Szymanski Sylwester

Classifications

• G01L19/0046

  using isolation membranes (G01L13/026 and G01L19/0645 take precedence) · CPC title

• G01L11/06 Primary

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• G01S7/539

  using analysis of echo signal for target characterisation; Target signature; Target cross-section · CPC title

• G01S15/88

  Sonar systems specially adapted for specific applications (seismic or acoustic prospecting or detecting G01V1/00) · CPC title

• G01F1/666

  by detecting noise and sounds generated by the flowing fluid · CPC title