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US5614677A Expired / Lapsed US ⏱️ 0.0 years remaining

Diaphragm gage for measuring the pressure of a fluid

Assignee: Fresenius SE and Co KGaA
•
Filing: 1995-05-24
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Granted: 1997-03-25
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Expires: 2015-05-24
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Abstract

Abstract Apparatus for measuring the pressure of a fluid includes a first pressure transmission element in form of a membrane in contact with a pressure sensor, and a second pressure transmission element in form of a membrane which is acted upon by a fluid whose pressure is to be determined. The first membrane has a peripheral area which is pressed against the second membrane in such a manner that the space between the first and second membranes is sealed off from outside and is of a size as small as possible. Both membranes thus move in synchronism in dependence of the fluid pressure so that positive as well as negative pressures can be measured.

Inventors

  • 👤 Ralf Wamsiedler
  • 👤 Ralf Wojke
  • 👤 Walter Pieper
  • 👤 Horst Christmann-Braun

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 01:13
CPC Classifications
G; G01; G01L; G01L19/00; G01L19/0007; G01L19/0023; A; A61; A61M; A61M1/00; A61M1/36; A61M1/3621; A61M1/3639; A61M1/3641; G01L19/06; G01L19/0627; G01L19/0645; G01L19/14; G01L19/142; G01L19/144

Claims Analysis

Total Claims: 20
Claim 1
Independent Claim 136 words
Apparatus for measuring the pressure of a fluid, comprising: a first pressure transmission element; a pressure sensor operatively connected with said first pressure transmission element; and a second pressure transmission element acted on by a fluid, said first pressure transmission element having a border area which is pressed through a translational force in an axial direction against said second transmission element in such a manner that a space between said first and second pressure transmission elements is sealed off from outside and is of a size as small as possible so as to effect a substantially synchronous movement of the first and second pressure transmission elements in dependence of the pressure of the fluid acting on the second pressure transmission element and thereby to allow a direct measurement of the fluid pressure by the pressure sensor.
Claim 2
Dependent Claim 136 words
Apparatus for measuring the pressure of a fluid, comprising: a first pressure transmission element; a pressure sensor operatively connected with said first pressure transmission element; and a second pressure transmission element acted on by a fluid, said first pressure transmission element having a border area which is pressed through a translational force in an axial direction against said second transmission element in such a manner that a space between said first and second pressure transmission elements is sealed off from outside and is of a size as small as possible so as to effect a substantially synchronous movement of the first and second pressure transmission elements in dependence of the pressure of the fluid acting on the second pressure transmission element and thereby to allow a direct measurement of the fluid pressure by the pressure sensor.
Claim 3
Dependent Claim 60 words
Apparatus as defined in claim 1 wherein said first pressure transmission element is pressed with its border area against said second pressure transmission element in such a manner that the space between the first and second transmission elements is sealed off from outside and both pressure transmission elements are arranged directly above each other without inclusion of air or liquid.
Claim 4
Dependent Claim 37 words
Apparatus as defined in claim 1, further comprising a clamping fixture for securing said second pressure transmission element, said clamping fixture having an opening for allowing a communication of said second pressure transmission element with the fluid.
Claim 5
Dependent Claim 32 words
Apparatus as defined in claim 1, further comprising a guide mechanism in opposition to said clamping fixture for receiving and pressing said first pressure transmission element against said second pressure transmission element.
Claim 6
Dependent Claim 24 words
Apparatus as defined in claim 4, further comprising a spring element for loading said pressure sensor in direction of said first pressure transmission element.
Claim 7
Dependent Claim 25 words
Apparatus as defined in claim 3 wherein said second pressure transmission element is secured in said clamping fixture across said opening of said clamping fixture.
Claim 8
Dependent Claim 25 words
Apparatus as defined in claim 6, further comprising a tension ring for retaining said second pressure transmission element across said opening of said clamping fixture.
Claim 9
Dependent Claim 42 words
Apparatus as defined in claim 6, further comprising an elevation received in said clamping fixture, said elevation projecting beyond and extending around said opening, with said second pressure transmission element being stretched across said opening of said clamping fixture via said elevation.
Claim 10
Dependent Claim 15 words
Apparatus as defined in claim 8 wherein said elevation is formed by a O ring.
Claim 11
Dependent Claim 20 words
Apparatus as defined in claim 1 wherein said first pressure transmission element forms a lower area of said pressure sensor.
Claim 12
Dependent Claim 40 words
Apparatus as defined in claim 3, further comprising a pressure measuring chamber formed with two connectors for attachment of a tube for conducting the fluid, said second pressure transmission and said clamping fixture being arranged adjacent said pressure measuring chamber.
Claim 13
Dependent Claim 15 words
Apparatus as defined in claim 11 wherein said pressure measuring chamber is of cylindrical configuration.
Claim 14
Dependent Claim 27 words
Apparatus as defined in claim 12, further comprising a volume-reducing elevation in the area of said pressure measuring chamber in opposition to said second pressure transmission element.
Claim 15
Dependent Claim 15 words
Apparatus as defined in claim 13 wherein said volume-reducing elevation is of truncated cone shape.
Claim 16
Dependent Claim 23 words
Apparatus as defined in claim 1 wherein each of said first and second pressure transmission elements is provided in form of a membrane.
Claim 17
Dependent Claim 16 words
Apparatus as defined in claim 15 wherein said second pressure transmission element is a silicon membrane.
Claim 18
Dependent Claim 11 words
Use of an apparatus of claim 1 for non-invasive pressure measurement.
Claim 19
Dependent Claim 16 words
Use of an apparatus of claim 1 for non-invasive pressure measurement at a blood tube system.
Claim 20
Dependent Claim 20 words
Use of an apparatus of claim 1 for non-invasive pressure measurement at a blood tube system of a dialysis machine.

References Cited (Backward Citations)

US4185641A Cited
DE2930869C2 Cited
EP0130441A2 Cited
US4541282A Cited
EP0303979A2 Cited
US4856340A Cited
US4885983A Cited
WO1993024817A1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2000-03-24 2000-09-23 2001-03-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2004-03-24 2004-09-23 2005-03-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2008-03-24 2008-09-23 2009-03-25 $7700.00 Window Closed / Lapsed

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