RELATIVE PRESSURE MEASUREMENT RECORDER FOR DETERMINING A FIRST PRESSURE OF A MEDIUM

Abstract

A relative pressure measuring transducer includes a process adapter having a basic body, which includes a pressure sensitive process diaphragm, a first pressure transfer line and a pressure sensor. A pressure-sensitive reference pressure diaphragm is also provided. The basic body includes a second pressure transfer line, which leads the reference pressure from the reference pressure diaphragm to the pressure sensor and supplies a second area of the pressure sensor with the reference pressure. A housing adapter is embodied to surround the process adapter at the reference pressure diaphragm. The housing adapter is arranged in such a manner relative to the process adapter that in the region of the reference pressure diaphragm an intermediate space is formed between the housing adapter and the process adapter, and in the housing adapter there is a passageway, which connects the intermediate space with the environment of the relative pressure measuring transducer.

Claims

1-14. (canceled)

15. Relative pressure measuring transducer for determining a first pressure of a medium, comprising a process adapter having a basic body, wherein, in a first, medium near, end region of the basic body, a pressure-sensitive process diaphragm is provided, wherein the basic body includes a first pressure transfer line, which is embodied to lead the first pressure of the medium from the process diaphragm to a pressure sensor arranged in a cavity of the basic body and to supply a first area of the pressure sensor with the first pressure of the medium, wherein in a second, medium far, region of the basic body, a pressure-sensitive reference pressure diaphragm is provided, which is supplied with a reference pressure present in the environment of the relative pressure measuring transducer wherein the basic body includes a second pressure transfer line, which is embodied to lead the reference pressure from the reference pressure diaphragm to the pressure sensor and to supply a second area of the pressure sensor with the reference pressure, and a housing adapter, which is embodied to surround the process adapter at least in the region of the reference pressure diaphragm and is connected with the process adapter in at least one connection region, wherein the housing adapter is arranged in such a manner relative to the process adapter that in the region of the reference pressure diaphragm an intermediate space is formed between the housing adapter and the process adapter, wherein there is arranged in the housing adapter a passageway, which connects the intermediate space with the environment of the relative pressure measuring transducer.

16. The relative pressure measuring transducer as claimed in claim 15, wherein a moisture impermeable filter element is arranged in the region of the passageway.

17. The relative pressure measuring transducer as claimed in claim 15, wherein a moisture adsorbing material is arranged in the intermediate space.

18. The relative pressure measuring transducer as claimed in claim 17, wherein provided as moisture adsorbing material is a formed material comprising a polymer matrix and zeolite.

19. The relative pressure measuring transducer as claimed in 15, wherein the reference pressure diaphragm is arranged essentially perpendicularly to the process diaphragm on a lateral surface of the basic body of the process adapter.

20. The relative pressure measuring transducer as claimed in claim 15, wherein the process adapter has a first connection region, which is embodied for connection with a process connection.

21. The relative pressure measuring transducer as claimed in 15, wherein the housing adapter has a second connection region, which is embodied for connection with a housing.

22. The relative pressure measuring transducer as claimed in claim 15, wherein an electrically insulating bushing is arranged adjoining the second area of the pressure sensor supplied with the reference pressure, wherein the second pressure transfer line passes through the bushing.

23. The relative pressure measuring transducer as claimed in claim 22, wherein the bushing is a glass-metal bushing.

24. The relative pressure measuring transducer as claimed in 22, wherein an orientation element is provided, which is arranged and embodied in such a manner that the bushing is orientable relative to the basic body by means of the orientation element.

25. The relative pressure measuring transducer as claimed in 24, wherein the orientation element is a pin.

26. The relative pressure measuring transducer as claimed in 15, wherein at least one electronics is arranged in a cavity of the housing adapter.

27. The relative pressure measuring transducer as claimed in claim 15, wherein the process diaphragm and/or the reference pressure diaphragm are/is connected with the basic body by means of a weld.

28. The relative pressure measuring transducer as claimed in claim 15, wherein the housing adapter is connected in the at least one connection region gas tightly with the process adapter.

Description

[0033] FIG. 1a first embodiment of the relative pressure measuring transducer of the invention; and

[0034] FIG. 2 a second embodiment of the relative pressure measuring transducer of the invention.

[0035] A first embodiment of a relative pressure measuring transducer 1 of the invention is shown in FIG. 1. The relative pressure measuring transducer 1 has two basic parts, the process adapter 3 with a basic body 4 and the housing adapter 10. The two basic parts are connected together, especially gas tightly, in at least one connection region 11, for example, by a weld 20. The process adapter 3 includes an optional first connection region 3a, which is embodied for connection with a process connection (not shown), so that the relative pressure measuring transducer 1 can be located at a desired measuring point. The housing adapter 10 can, furthermore, have a second connection region 10a, which is embodied for connection with a housing 16 (schematically illustrated).

[0036] In a first, medium 2 near, end region of the basic body 4 of the process adapter 3, a pressure-sensitive process diaphragm 5 is arranged, which is supplied with a first pressure p1 of the medium 2. In a second, medium 2 far, region 4b of the basic body 4, a pressure-sensitive reference pressure diaphragm 9 is arranged, which is supplied with a reference pressure p2 present in the environment of the relative pressure measuring transducer 1. The process diaphragm 5 and/or the reference diaphragm 9 are connected with the basic body 4, for example, by means of a weld. The reference pressure diaphragm 9 is arranged, by way of example, on a lateral surface 4c of the basic body 4 essentially perpendicularly to the process diaphragm 5.

[0037] The first pressure p1 and the reference pressure p2 are led, respectively, by means of a first pressure transfer line 6a and a second pressure transfer line 6b from the process diaphragm 5 and from the reference pressure diaphragm 9 to the pressure sensor 8, such that the pressure sensor 8 is supplied at a first area 8a with the first pressure p1 and at a second area 8b opposite the first area 8a with the reference pressure p2. The pressure sensor 8 is arranged in a cavity 4d of the basic body 4. The first pressure transfer line 6a and the second pressure transfer line 6b are filled with pressure transfer liquid, for example, via separate filling openings or small filling tubes.

[0038] Provided adjoining the second area 8b of the pressure sensor 8 is an optional bushing 17, which is electrically insulating and serves for leading electrical lines to the pressure sensor 8. The electrical lines lead from the pressure sensor 8 through the bushing 17, for example, to at least one electronics 19, which is arranged optionally in a cavity 10b of the housing adapter 10. The second pressure transfer line 6b extends partially through the bushing 17, which is, for example, a glass-metal bushing. For sealing the second pressure transfer line 6b from the first pressure transfer line 6a, the second pressure transfer line 6b can be welded by means of a welding method in such a manner that the weld seam adjoins the second pressure transfer line 6b, without closing it.

[0039] In order to orient the section of the second pressure transfer line 6b extending through the process adapter 3 with the section of the second pressure transfer line 6b extending through the bushing 17 relative to one another, thus to align them relative to one another, an orientation element 18 can be provided. The orientation element 18 is, for example, a pin and is embodied and arranged in such a manner that the bushing 17 is orientable, i.e. assumes a predetermined orientation, relative to the basic body 4 by means of the orientation element 18.

[0040] The housing adapter 10 is embodied and arranged in such a manner that it surrounds the process adapter 3 at least in the region of the reference pressure diaphragm 9 and an intermediate space 12 is formed in the region of the reference pressure diaphragm 9 between the housing adapter 10 and the process adapter 3. In order that the reference pressure p2 can act as environmental air on the reference pressure diaphragm 9, a passageway 13 is arranged in the housing adapter 10, such that the intermediate space 12 is connected with the environment of the relative pressure measuring transducer 1.

[0041] For protection against penetration of moisture into the intermediate space 12, a moisture impermeable filter element 14 can be arranged in the region of the passageway 13. Additionally or alternatively, a moisture adsorbing material 15 shown in FIG. 2 can be arranged in the intermediate space 12. For example, provided as moisture adsorbing material 15 can be a formed body composed of at least zeolite and a polymer matrix.

LIST OF REFERENCE CHARACTERS

[0042] 1 relative pressure measuring transducer [0043] 2 medium [0044] 3 process adapter [0045] 3a first connection region [0046] 4 basic body [0047] 4a end region of the basic body [0048] 4b second region of the basic body [0049] 4c lateral surface [0050] 4d cavity of the basic body [0051] 5 process diaphragm [0052] 6a first pressure transfer line [0053] 6b second pressure transfer line [0054] 8 pressure sensor [0055] 8a first area [0056] 8b second area [0057] 9 reference pressure diaphragm [0058] 10 housing adapter [0059] 10a second connection region [0060] 10b cavity of the housing adapter [0061] 11 connection region [0062] 12 intermediate space [0063] 13 passageway [0064] 14 filter element [0065] 15 moisture adsorbing material [0066] 16 housing [0067] 17 bushing [0068] 18 orientation element [0069] 19 electronics [0070] 20 weld