Search

US-20260126333-A1 - Pressure Sensor and Pressure Interface Thereof

US20260126333A1US 20260126333 A1US20260126333 A1US 20260126333A1US-20260126333-A1

Abstract

A pressure sensor includes a pressure interface and a strain gauge. The pressure interface includes a cylindrical ceramic base and a ceramic diaphragm provided at one end of the ceramic base. The strain gauge is connected to the ceramic diaphragm. The ceramic base and the ceramic diaphragm are integrally formed.

Inventors

  • Pengcheng FENG
  • Jianhai (Ross) Qiu
  • Xuetang Zhao

Assignees

  • MEASUREMENT SPECIALTIES (CHINA) LTD.

Dates

Publication Date
20260507
Application Date
20251104
Priority Date
20241104

Claims (18)

  1. 1 . A pressure sensor, comprising: a pressure interface including a ceramic base and a ceramic diaphragm disposed at an end of the ceramic base, the ceramic base and the ceramic diaphragm are integrally formed; and a strain gauge connected to the ceramic diaphragm.
  2. 2 . The pressure sensor of claim 1 , wherein the ceramic base is cylindrical.
  3. 3 . The pressure sensor of claim 1 , wherein the strain gauge is adhered to the ceramic diagram via a glass.
  4. 4 . The pressure sensor of claim 3 , wherein the glass is melted by a glass micro-melting process.
  5. 5 . The pressure sensor of claim 1 , wherein the strain gauge is made of a semiconductor material.
  6. 6 . The pressure sensor of claim 1 , further comprising a cap covering an end of the pressure interface having the ceramic diaphragm.
  7. 7 . The pressure sensor of claim 6 , wherein the ceramic base has a flange extending radially outward.
  8. 8 . The pressure sensor of claim 7 , wherein the cap is adhered to the flange.
  9. 9 . The pressure sensor of claim 6 , further comprising a circuit board on the ceramic diaphragm.
  10. 10 . The pressure sensor of claim 9 , wherein the circuit board is electrically connected to the strain gauge via a bond wire.
  11. 11 . The pressure sensor of claim 10 , wherein a cable connected to the circuit board is adhered to the circuit board.
  12. 12 . The pressure sensor of claim 11 , wherein the cable extends through a wire passing hole in the cap.
  13. 13 . The pressure sensor of claim 6 , wherein a side wall of the ceramic base has a groove, and further comprising a sealing ring disposed in the groove.
  14. 14 . The pressure sensor of claim 13 , wherein the groove is in an end face of the ceramic base opposite the ceramic diaphragm.
  15. 15 . The pressure sensor of claim 1 , wherein the ceramic base has a installation groove by which the pressure sensor is installed on a component to be measured.
  16. 16 . The pressure sensor of claim 6 , wherein the cap has an installation recess by which the pressure sensor is installed on a component to be measured.
  17. 17 . A pressure interface for a pressure sensor, the pressure interface comprising: a ceramic base; and a ceramic diaphragm disposed at an end of the ceramic base, the ceramic base and the ceramic diaphragm are integrally formed.
  18. 18 . The pressure interface of claim 17 , wherein the ceramic base is cylindrical.

Description

CROSS-REFERENCE TO RELATED APPLICATION This application claims the benefit of the filing date under 35 U.S.C. § 119(a)-(d) of Chinese Application No. 202411563368.9, filed on Nov. 4, 2024. FIELD OF THE INVENTION Embodiments of the present disclosure relate to a pressure sensor and a pressure interface of the pressure sensor. BACKGROUND OF THE INVENTION Pressure sensors are one of the most widely used sensors in industrial applications, and are extensively applied in water conservancy, hydropower, railway transportation, intelligent buildings, petrochemical industries, and so on. Currently, the pressure sensors typically comprise a pressure interface and a strain gauge, in which the strain gauge is adhered to a diaphragm of the pressure interface via glass, which is melted using high-temperature micro-melting technology. When external pressure acts on the sensor, the diaphragm undergoes slight deformation, which subsequently causes changes in a resistance of the strain gauge. However, the existing diaphragms are usually made of stainless steel, having the following drawbacks: (1) significant difference in thermal expansion coefficients between glass and stainless steel diaphragm leads to poor thermal stability of the resistance of the strain gauge; (2) the typical thickness of the glass under 0.1 mm results in low insulation and dielectric strengths between the strain gauge and the stainless steel diaphragm, making it difficult for the sensors to obtain enhanced safety certification; and (3) the stainless steel diaphragm requires complex pretreatment processes including heat treatment, sandblasting, ultrasonic cleaning and so on; (4) the stainless steel pressure interfaces are typically machined by computer numerical control (CNC), resulting in high costs and relatively low burst pressure and overpressure. SUMMARY OF THE INVENTION A pressure sensor includes a pressure interface having a ceramic base and a ceramic diaphragm disposed at an end of the ceramic base. The ceramic base and the ceramic diaphragm are integrally formed. The pressure sensor includes a strain gauge connected to the ceramic diaphragm. BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described by way of example with reference to the accompanying figures, of which: FIG. 1 is a schematic perspective view of a structure of a pressure sensor according to a first exemplary embodiment of the present disclosure; FIG. 2 is a cross-sectional view of the pressure sensor shown in FIG. 1; FIG. 3 is a schematic perspective view of a structure of a pressure sensor according to a second exemplary embodiment of the present disclosure; and FIG. 4 is a part cross-sectional view of the pressure sensor shown in FIG. 3. DETAILED DESCRIPTION Although the present disclosure will be fully described with reference to the drawings containing embodiments of the present disclosure, it should be understood that those skilled in the art may modify the present disclosure described herein and obtain the technical effect of the present disclosure. Therefore, it is necessary to understand that the above description is a broad disclosure for those skilled in the art and is not intended to limit the exemplary embodiments described in the present disclosure. In addition, in the following detailed description, for the sake of explanation, numerous specific details are set forth in order to provide a thorough understanding of the disclosed embodiments. It will be apparent, however, that one or more embodiments may also be practiced without these specific details. In other instances, well-known structures and devices are illustrated schematically in order to simplify the drawing. As shown in FIG. 1 and FIG. 2, according to a first exemplary embodiment of the present disclosure, the pressure sensor includes a pressure interface 10 and a strain gauge 20. The pressure interface 10 includes a ceramic base 11 that is substantially cylindrical and a ceramic diaphragm 12 provided at one end of the ceramic base 11. The strain gauge 20 is connected to the ceramic diaphragm 12, so that when the pressure medium to be measured (e.g., gas or liquid) enters a cavity of the ceramic base 11 through an opening end of the ceramic diaphragm 12, the ceramic diaphragm 12 will deform, and the magnitude of this deformation is proportional to the pressure of the pressure medium to be measured. When the ceramic diaphragm 12 deforms, the ceramic diaphragm 12 drives the strain gauge 20 to deform, and the strain gauge 20 deforms along with the deformation of the ceramic diaphragm 12, which further causes a change in the resistance of the strain gauge 20. By testing the change in the resistance of the strain gauge 20, the pressure of the medium to be measured can be obtained. In this embodiment, the ceramic base 11 and the ceramic diaphragm 12 of the pressure interface 10 are integrally formed, for example by sintering in a mold. Since the ceramic base 11 and the ceramic diaphragm 12 of the pres