Pressure sensor using compressible sensor body

• US 20060278005A1
• Filed: 05/26/2005
• Published: 12/14/2006
• Est. Priority Date: 05/26/2005
• Status: Active Grant

• Current Assignee: Rosemount Incorporated (Emerson Electric Company)
• Original Assignee: Rosemount Incorporated (Emerson Electric Company)
• Inventors: Hedtke, Robert C., Broden, David A.
• Granted Patent: US 7,401,522 B2
• Time in Patent Office: Days
• US Class Current: 73/716
• CPC Class Codes: G01L 13/025 using diaphragms
• CPC Class Codes: G01L 9/0075 using a ceramic diaphragm, e.g. alumina, fused quartz, glass

Abstract

A pressure sensor including a deformable sensor body formed of a compressible material. A deformation sensor is embedded in the deformable sensor body and has an electrical property which changes in response to deformation of the deformable sensor body. Electrical connections which extend from outside the deformable sensor body to the embedded deformation sensor to provide an indication of an applied line pressure or differential pressure.

Claims

1. A pressure sensor, comprising;

a deformable sensor body formed of a compressible material;

an embedded deformation sensor embedded in the deformable sensor body having an electrical property which changes in response to deformation of the deformable sensor body; and

electrical connections which extend from outside the deformable sensor body to the embedded deformation sensor.

2. The apparatus of claim 1 wherein the deformable sensor body comprises a glass sensor body formed of a compressible glass material.

3. The apparatus of claim 1 wherein the deformation sensor comprises a strain gauge.

4. The apparatus of claim 3 wherein the strain gauge is carried on a substrate.

5. The apparatus of claim 3 wherein the strain gauge comprises a resistive element having a resistance which varies in response to strain.

6. The apparatus of claim 1 wherein the deformation sensor includes a compensation sensor.

7. The apparatus of claim 1 including a temperature sensor.

8. The apparatus of claim 1 wherein the deformation sensor comprises a capacitor.

9. The apparatus of claim 1 wherein the pressure sensor includes a diaphragm in the sensor body.

10. The apparatus of claim 9 wherein the diaphragm is configured to deflect in response to an applied pressure.

11. The apparatus of claim 10 wherein the diaphragm is configured to deflect in response to a pressure differential applied to the pressure sensor.

12. The apparatus of claim 1 wherein the pressure sensor couples to a process fluid through an isolation fluid.

13. The apparatus of claim 1 wherein the pressure sensor is configured to directly contact a process fluid.

14. A process control transmitter including transmitter circuitry coupled to the pressure sensor of claim 1.

15. The apparatus of claim 14 wherein the transmitter circuitry is configured to determine a differential pressure and a line pressure based upon electrical characteristics of the pressure sensor.

16. The apparatus of claim 1 wherein the electrical property of the embedded deformation sensor is related to an applied line pressure.

17. The apparatus of claim 1 wherein the electrical property of the embedded deformation sensor is related to an applied differential pressure.

19. The method of claim 1 wherein deformation is measured with a strain gauge.

20. The method of claim 19 wherein the strain gauge is embedded in the sensor body.

18. A method of measuring pressure, comprising:

determining differential pressure based upon deflection of a diaphragm carried in a sensor body; and

determining line pressure based upon deformation of the sensor body.