Pressure sensor having a compressible element

• US 9,291,514 B2
• Filed: 12/22/2011
• Issued: 03/22/2016
• Est. Priority Date: 12/27/2010
• Status: Active Grant

• Current Assignee: TDK Electronics AG (TDK Corporation)
• Original Assignee: Epcos AG (TDK Corporation)
• Inventors: Wohlgemuth, Christian
• Primary Examiner(s): Allen, Andre
• Application Number:
  US13/997,627
• Publication Number:
  US 20130340532A1
• Time in Patent Office: 1,552 Days
• Field of Search: 73700-756
• US Class Current: 1/1
• CPC Class Codes: G01L 19/06 Means for preventing overload or deleterious influence of the measured medium on the measuring device or vice versa
• CPC Class Codes: G01L 19/0618 Overload protection
• CPC Class Codes: G01L 19/0645 using isolation membranes, specially adapted for protection
• CPC Class Codes: G01L 19/0654 against moisture or humidity
• CPC Class Codes: G01L 7/08 of the flexible-diaphragm type

Abstract

The invention relates to a pressure sensor (1, 41) comprising a chamber (3) in which a sensor element (4) for measuring pressure is arranged. The pressure sensor (1, 41) further comprises a compressible element (6, 7) for overpressure protection, said compressible element (6, 7) being arranged outside the chamber (3).

Claims

1. A pressure sensor, comprising:

a chamber in which a sensor element for measuring a pressure is arranged; and

a compressible element for protecting against excess pressure,

wherein the compressible element is arranged outside the chamber,

wherein the compressible element is at least partially surrounded by a fluid medium,

wherein the compressible element is adapted to decrease its volume when the pressure in the fluid medium rises above a limit pressure, and

wherein the volume is taken up by the fluid medium, leading to a decrease of pressure in the fluid medium.

2. The pressure sensor according to claim 1, wherein the chamber is bounded by a pressure-sensitive region.

3. The pressure sensor according to claim 1 or 2, further comprising:

a pressure line, which is fillable with the fluid medium, for directing the pressure of the medium onto the pressure-sensitive region,

wherein the compressible element is arranged on the pressure line.

4. The pressure sensor according to claim 1, wherein the pressure-sensitive region is in the form of a membrane.

5. The pressure sensor according to claim 4, wherein the membrane is a metallic membrane.

6. The pressure sensor according to claim 1, further comprising:

a housing,

wherein the pressure line extends in the housing.

7. The pressure sensor according to claim 6, wherein the housing has an inner wall which is lined with the compressible element.

8. The pressure sensor according to claim 1, wherein the pressure line leads through the compressible element.

9. The pressure sensor according to claim 1, wherein the pressure line extends vertically toward the pressure-sensitive region.

10. The pressure sensor according to claim 1, wherein the pressure line extends at an inclination angle toward the pressure-sensitive region.

11. The pressure sensor according to claim 1, wherein the pressure line has sections which have different diameters.

12. The pressure sensor according to claim 11, wherein the section having the smallest diameter is bounded by the compressible element.

13. The pressure sensor according to claim 1, wherein the total volume of the compressible elements is at least 50% of the volume of the pressure line.

14. The pressure sensor according to claim 1, wherein the distance of the compressible element from the pressure-sensitive region is less than or equal to 1000 μ

m.

15. The pressure sensor according to claim 1, wherein the chamber is oil-filled.

16. The pressure sensor according to claim 1, wherein the compressible element is formed from a foam-like or rubber-like material.

17. The pressure sensor according to claim 1, wherein the chamber is closed by a membrane and the compressible element is located on a different side of the membrane than the sensor element.