Diaphragm pressure gauge with monitoring function

• US 10,151,657 B2
• Filed: 05/26/2016
• Issued: 12/11/2018
• Est. Priority Date: 05/26/2015
• Status: Active Grant

• Current Assignee: WIKA Alexander Wiegand SE & Company KG
• Original Assignee: WIKA Alexander Wiegand SE & Company KG
• Inventors: Kaufmann, Reimund, Massong, Andreas, Mottl, Karsten
• Primary Examiner(s): Fitzgerald, John
• Assistant Examiner(s): Morello, Jean
• Application Number:
  US15/164,921
• Publication Number:
  US 20160349128A1
• Time in Patent Office: 929 Days
• Field of Search: None
• CPC Class Codes: G01L 19/16 Dials; Mounting of dials
• CPC Class Codes: G01L 7/063 with mechanical transmitting or indicating means
• CPC Class Codes: G01L 7/084 with mechanical transmitting or indicating means

Abstract

A diaphragm pressure gauge, in which a measuring spring is monitored in regard to integrity in that on the side, facing away from the process pressure, of the measuring spring a vacuum chamber is formed to which vacuum is applied and which is controlled by means of a vacuum monitoring device to maintain the vacuum.

Claims

1. A diaphragm pressure gauge comprising:

at least one plate-shaped measuring spring;

a push rod coupled to the measuring spring;

a measuring mechanism, which is configured to convert a mechanical movement into a pointer deflection on a display dial, wherein the push rod transmits a movement of the measuring spring, the movement caused by an application of pressure by a process pressure in a process region to the measuring mechanism to produce a pointer deflection;

a fluid-tight vacuum chamber to which vacuum is applied is formed on a side of the measuring spring facing away from the process region;

a vacuum monitoring device that measures and indicates a value of the vacuum in the vacuum chamber;

a base element, wherein an outer periphery of the side of the measuring spring facing away from the process region is attached to a bottom surface of the base element;

a socket, a lower end of the socket being at least partially inserted inside a cavity of the base element, the cavity recessed from an upper surface of the base element, and an upper end of the socket being inserted inside of a housing of the display dial;

a capillary line connecting the vacuum chamber to the vacuum monitoring device, such that the capillary line is provided inside of the socket and inside of the housing of the display dial.

2. The diaphragm pressure gauge according to claim 1, wherein the vacuum chamber on the side of the measuring spring facing away from the process region has a bellows, which allows a relative movement of the push rod to the measuring mechanism of the diaphragm pressure gauge.

3. The diaphragm pressure gauge according to claim 1, wherein the vacuum monitoring device has a separate pressure measuring device.

4. The diaphragm pressure gauge according to claim 1, wherein the vacuum monitoring device has a Bourdon pressure gauge, which has a display that is integratable into the display dial of the diaphragm pressure gauge.

5. The diaphragm pressure gauge according to claim 1, wherein, on the side of the measuring spring facing away from the process region, a support arrangement with a predefined geometry is provided, which in the case of overload or too high pressure on the side of the measuring spring facing the process region supports the measuring spring to prevent damage.

6. The diaphragm pressure gauge according to claim 1, wherein the vacuum monitoring device is provided with an emitter for emitting a signal or an electrical signal when the value of the vacuum in the vacuum chamber falls below a predetermined vacuum value.

7. The diaphragm pressure gauge according to claim 6, wherein the color coding includes red/green fields.

8. The diaphragm pressure gauge according to claim 1, wherein, the vacuum chamber extends from the side of the measuring spring facing away from the process region, through the cavity of the base element, through a central cavity of the socket and terminating in the upper end of the socket that is inserted inside of the housing of the display dial.

9. The diaphragm pressure gauge according to claim 1, wherein the vacuum monitoring device is provided inside of the housing of the display dial.

10. The diaphragm pressure gauge according to claim 1, wherein the vacuum monitoring device has a display, which by a color coding indicates a maintenance of a predetermined value of the vacuum in the vacuum chamber and/or a fluid-tight state of the measuring spring.

11. The diaphragm pressure gauge according to claim 1, wherein a pressure characteristic of the diaphragm pressure gauge is configured substantially with consideration of the characteristic of the measuring spring, of the characteristic of the bellows, and of the value of the vacuum in the vacuum chamber in relation to the area of the measuring spring.

12. The diaphragm pressure gauge according to claim 5, wherein the support arrangement on the side of the measuring spring facing away from the process region is an arrangement with a stepped geometry and/or has an arrangement adapted in shape to the measuring spring.

13. The diaphragm pressure gauge according to claim 1, wherein the vacuum chamber is formed by the measuring spring and a further membrane, which are coupled to one another by a coupling element to transmit a deflection of the measuring spring to the further membrane.