Hydraulic measuring mechanism with coplanar pressure inputs and pressure difference sensor having such a measuring mechanism

Patent metadata

Field	Value
Publication number	US-9797796-B2
Application number	US-201314652821-A
Country	US
Kind code	B2
Filing date	Dec 6, 2013
Priority date	Dec 21, 2012
Publication date	Oct 24, 2017
Grant date	Oct 24, 2017

Abstract

A hydraulic measuring mechanism for registering pressure differences, comprising a measuring mechanism platform having a process connection surface and two pressure input openings, in which, in each case, a pressure tube is arranged, which protrudes from a rear side of the measuring mechanism platform to support a pressure difference measuring cell, wherein the pressure tubes are connected pressure-tightly with the measuring mechanism platform from the process connection surface.

First claim

The invention claimed is:

1. A hydraulic measuring mechanism for registering pressure differences, comprising:
a measuring mechanism platform having a process connection surface facing essentially in one direction, said measuring mechanism platform has a first pressure input opening, which extends from said process connection surface of said measuring mechanism platform to a rear surface of said measuring mechanism platform, said measuring mechanism platform has a second pressure input opening, which extends from said process connection surface of said measuring mechanism platform to the rear surface of said measuring mechanism platform;
a first isolating diaphragm, which closes said first pressure input opening on a process connection surface end of said first pressure input opening;
a second isolating diaphragm, which closes said second pressure input opening on a process connection surface end of said second pressure input opening;
a first pressure tube, which is arranged with a section in said first pressure input opening, said first pressure tube protrudes out from the rear surface of said measuring mechanism platform; and
a second pressure tube, which is arranged with a section in said second pressure input opening, wherein said second pressure tube protrudes out from the rear surface of said measuring mechanism platform; wherein:
said first and said second pressure tubes are connected pressure-tightly with said measuring mechanism platform;
at least said first pressure tube is connected from said process connection surface side pressure-tightly with said measuring mechanism platform; and
said first pressure tube and said second pressure tube are connected pressure-tightly with said measuring mechanism platform by joining, especially welding.

2. The hydraulic measuring mechanism as claimed in claim 1 , wherein:
said first pressure tube and said second pressure tube are connected from said process connection surface side pressure-tightly with said measuring mechanism platform.

3. The hydraulic measuring mechanism as claimed in claim 1 , wherein:
at least one pressure tube extends in said measuring mechanism platform inclined relative to a surface normal of said process connection surface.

4. The hydraulic measuring mechanism as claimed in claim 1 , further comprising:
at least a first diaphragm bed body, which has a corrugated diaphragm bed on a surface facing away from said measuring mechanism platform, wherein:
said diaphragm bed body is connected pressure-tightly with said measuring mechanism platform from said process connection surface side after the pressure-tight connecting of said at least a first pressure tube with said measuring mechanism platform.

5. The hydraulic measuring mechanism as claimed in claim 4 , wherein:
said at least one isolating diaphragm is formed by pressing against the corrugated diaphragm bed of said isolating diaphragm bed body.

6. The hydraulic measuring mechanism as claimed in claim 1 , wherein:
no corrugated diaphragm bed is present between at least one isolating diaphragm and said pressure input opening closed by it.

7. A pressure difference sensor comprising:
a hydraulic measuring mechanism, comprising: a measuring mechanism platform having a process connection surface facing essentially in one direction, said measuring mechanism platform has a first pressure input opening, which extends from said process connection surface of said measuring mechanism platform to a rear surface of said measuring mechanism platform, said measuring mechanism platform has a second pressure input opening, which extends from said process connection surface of said measuring mechanism platform to the rear surface of said measuring mechanism platform; a first isolating diaphragm, which closes said first pressure input opening on a process connection surface end of said first pressure input opening; a second isolating diaphragm, which closes said second pressure input opening on a process connection surface end of said second pressure input opening; a first pressure tube, which is arranged with a section in said first pressure input opening, said first pressure tube protrudes out from the rear surface of said measuring mechanism platform; and a second pressure tube, which is arranged with a section in said second pressure input opening, wherein said second pressure tube protrudes out from the rear surface of said measuring mechanism platform; wherein: said first and said second pressure tubes are connected pressure-tightly with said measuring mechanism platform by joining, especially welding; and at least said first pressure tube is connected from said process connection surface side pressure-tightly with said measuring mechanism platform; and
a pressure difference measuring cell, wherein:
said the pressure difference measuring cell has a measuring cell platform with two measuring chambers in its interior, which are separated from one another by a measuring diaphragm;
said measuring chambers each have a measuring chamber opening;
a first of said measuring chambers is pressure-tightly connected to said first pressure tube and contactable with a first pressure through said first pressure tube;
a second of said measuring chambers is pressure-tightly connected to said second pressure tube and contactable with a second pressure through said second pressure tube;
said measuring diaphragm is elastically deformable as a function of a difference between the first pressure and the second pressure; and
said pressure difference measuring cell has a transducer for providing a signal dependent on the deformation of said measuring diaphragm.

8. The pressure difference sensor as claimed in claim 7 , wherein:
said pressure difference measuring cell is held by said pressure tubes.

9. The pressure difference sensor as claimed in claim 7 , wherein:
said two pressure tubes each have a branching;
in each case, a branch of a pressure tube is connected to one of said measuring chambers; and
the respectively other branch of a pressure tube has a sealable filling opening for filling the respective volumes of the pressure difference sensor communicating with the branch with a pressure transfer liquid.

10. The pressure difference sensor as claimed in claim 7 , wherein:
said measuring mechanism platform includes two sealable filling openings, each of which communicates with a pressure input opening;
said filling openings are provided for filling the respective volumes of the pressure difference sensor communicating with them with a pressure transfer liquid.

Assignees

• Endress Hauser Gmbh Co Kg

Inventors

• Lemke Benjamin
• Noack Michael
• Tham Anh Tuan
• Teipen Rafael

Classifications

• G01L9/0072

  using variations in capacitance · CPC title

• G01L13/06 Primary

  using electric or magnetic pressure-sensitive elements · CPC title

• G01L19/0023

  for flowthrough systems having a flexible pressure transmitting element · CPC title

• G01L13/025 Primary

  using diaphragms · CPC title