Separating membrane, diaphragm seal with a separating membrane of said type, and pressure measuring unit with a diaphragm seal of said type

Patent metadata

Field	Value
Publication number	US-12174079-B2
Application number	US-202017757541-A
Country	US
Kind code	B2
Filing date	Dec 1, 2020
Priority date	Dec 20, 2019
Publication date	Dec 24, 2024
Grant date	Dec 24, 2024

Abstract

A separating membrane includes: a planar edge region for the joining of the separating membrane to a diaphragm seal body; a working region offset in an axial direction relative to the edge region; and a transition region between the edge region and the working region, wherein the transition region extends over a radial region of not more than one quarter of an outer radius of the transition region, wherein the working region has a substantially planar center and an embossed pattern or undulation pattern between the center and an outer edge of the working region, wherein from the rest position to a point of deflection with a dimensionless pressure equivalent, the separating membrane has a characteristic curve in which, for a coefficient of determination R2 of a linear regression of the characteristic curve, the following applies: (1−R2)<1%.

First claim

The invention claimed is:

1. A separating membrane, comprising:
a planar edge region configured to facilitate joining of the separating membrane to a diaphragm seal body;
a working region offset in an axial direction relative to the edge region by at least three thicknesses of the separating membrane; and
a transition region between the edge region and the working region, which extends over a radial region of at least one eighth of an outer radius of the transition region, wherein the transition region extends over a radial region of not more than one quarter of the outer radius of the transition region,
wherein the working region has a substantially planar center whose radius is not less than one sixth of the outer radius of the transition region,
wherein the working region between the center and an outer edge of the working region includes an embossed pattern or undulation pattern,
wherein the edge region, working region, transition region, and center region of the separating membrane are configured such that a characteristic curve of the separating membrane, from a rest position to a point of deflection with a dimensionless pressure equivalent of not less than 250, has a coefficient of determination (R 2 ) of a linear regression of the characteristic curve for which the following applies: (1−R 2 )<0.01.

2. The separating membrane of claim 1 , wherein the transition region extends over a radial region of not less than one sixth of the outer radius of the transition region, and/or
wherein the transition region extends over a radial region of not more than one fifth of the outer radius of the transition region.

3. The separating membrane of claim 1 , wherein the separating membrane is configured such that, for the coefficient of determination (R 2 ) of the linear regression of the characteristic curve, the following applies: (1−R 2 )<0.0025.

4. The separating membrane of claim 1 , wherein the undulation pattern adjoins the planar center and extends to the outer edge of the working region.

5. The separating membrane of claim 1 , wherein an amplitude of the undulation pattern decreases from inside to outside.

6. The separating membrane of claim 1 , wherein the radius of the planar center is not more than one sixth of the outer radius of the transition region.

7. The separating membrane of claim 1 , wherein the undulation pattern has not more than seven half wave trains.

8. The separating membrane of claim 1 , wherein an innermost wave train of the undulation pattern between two extreme values of the wave train has an axial distance of not less than one membrane thickness.

9. The separating membrane of claim 1 , wherein an innermost wave train of the undulation pattern between two extreme values of the wave train has an axial distance of not more than two membrane thicknesses.

10. The separating membrane of claim 1 , wherein an outermost wave train of the undulation pattern between two extreme values of the wave train has an axial distance of not more than three quarters of a membrane thickness.

11. The separating membrane of claim 1 , wherein the transition region has a frustoconical shape.

12. The separating membrane of claim 1 , wherein an average wavelength of the undulation pattern is not less than six membrane thicknesses.

13. The separating membrane of claim 1 , wherein an average wavelength of the undulation pattern is not more than 10 membrane thicknesses.

14. The separating membrane of claim 1 , wherein the outer radius of the transition region is not less than 200 times the membrane thickness.

15. The separating membrane of claim 1 , wherein the outer radius of the transition region is not more than 360 times the membrane thickness.

16. The separating membrane of claim 1 , wherein, from the rest position to the point of deflection with the dimensionless pressure equivalent of not less than 250, the separating membrane has a substantially axisymmetrical shape.

17. A diaphragm seal, comprising:
a separating membrane according to claim 1 ; and
a diaphragm seal body, wherein the diaphragm seal body includes an annular support surface surrounding a membrane bed,
wherein the edge region of the separating membrane is joined to the support surface of the diaphragm seal body to define a diaphragm seal chamber between the diaphragm seal body and the separating membrane.

18. A pressure measuring unit, comprising:
a diaphragm seal according to claim 17 ;
a pressure sensor element; and
a hydraulic path in communication with the diaphragm seal chamber and configured to transfer a pressure prevailing in the diaphragm seal chamber to the sensor element via a transfer fluid,
wherein a total amount of the transfer fluid in the pressure chamber and in the hydraulic path is such that the separating membrane is deflected from its rest position to an extent that a pressure exerted on the transfer fluid by the separating membrane at temperatures between 300 K and 550 K exceeds the vapor pressure of the transfer fluid.

Assignees

• Endress Hauser Se Co Kg

Inventors

• Krumbholz Andreas
• Parrotto Davide
• Getman Igor

Classifications

• G01L19/0038

  being part of the housing (other details about the housing G01L19/14) · CPC title

• F16J3/02

  Diaphragms · CPC title

• G01L19/0046 Primary

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