Pressure sensor and pressure interface thereof

Abstract

A pressure sensor and a pressure interface are disclosed. The pressure sensor comprises: a pressure interface, wherein the pressure interface comprises a cylindrical ceramic base and a ceramic diaphragm arranged at one end part of the ceramic base; the ceramic diaphragm is connected with the ceramic base, the strain gauge is connected with the ceramic diaphragm, and the ceramic base and the ceramic diaphragm are integrally manufactured. As the pressure sensor adopts the ceramic base and the ceramic diaphragm which are integrated, additional assembly and sealing are not needed, the risk of leakage is avoided, and the cost is low at the same time. Moreover, the pressure sensor is made of a ceramic material which is in contact with the pressure medium, so that the pressure sensor can be applied to corrosive pressure media and the like.

Description

Technical Field

[0001] Embodiments of this disclosure relate to a pressure sensor and a pressure interface for the pressure sensor. Background Technology

[0002] Pressure sensors are one of the most commonly used sensors in industrial applications, widely used in industries such as water conservancy and hydropower, railway transportation, intelligent buildings, and petrochemicals. Current pressure sensors typically consist of a pressure interface and a strain gauge. The strain gauge is attached to the diaphragm of the pressure interface by melting the glass using high-temperature glass micro-melting technology. When external pressure is applied to the sensor, the diaphragm undergoes a slight deformation, which in turn causes a change in the resistance value of the strain gauge. However, existing diaphragms are usually made of stainless steel, which has the following disadvantages: (1) Due to the large difference in the coefficients of thermal expansion between glass and stainless steel diaphragms, the thermal stability of the strain gauge resistance is poor; (2) The thickness of the glass is usually less than 0.1 mm, resulting in low insulation strength and dielectric strength between the strain gauge and the stainless steel diaphragm, which makes it difficult for the sensor to pass ATEX increased safety certification; (3) The pretreatment process of stainless steel diaphragms is complex, including heat treatment, sandblasting, and ultrasonic cleaning; (4) Pressure interfaces made of stainless steel are usually machined using CNC, which is costly and has low burst pressure and overpressure. Summary of the Invention

[0003] The purpose of this disclosure is to address at least one aspect of the aforementioned problems and defects existing in the prior art.

[0004] According to one aspect of this disclosure, a pressure sensor is provided, the pressure sensor comprising: a pressure interface including a cylindrical ceramic base and a ceramic diaphragm disposed at one end of the ceramic base; and a strain gauge connected to the ceramic diaphragm, wherein the ceramic base and the ceramic diaphragm are integrally formed.

[0005] According to an exemplary embodiment of the present disclosure, the strain gauge is attached to the ceramic diaphragm via a glass micro-dissolution process.

[0006] According to an exemplary embodiment of this disclosure, the strain gauge is made of a semiconductor material.

[0007] According to an exemplary embodiment of the present disclosure, it further includes a cover disposed at one end of the pressure port where the ceramic diaphragm is located.

[0008] According to an exemplary embodiment of this disclosure, a radially outwardly extending flange is formed on the ceramic base, and the cover is attached to the flange.

[0009] According to an exemplary embodiment of the present disclosure, the pressure sensor further includes a circuit board located on the ceramic diaphragm, the circuit board being electrically connected to the strain gauge via a bonding wire.

[0010] According to an exemplary embodiment of this disclosure, a cable connected to the circuit board is attached to the circuit board and led out through a cable hole formed on the cover.

[0011] According to an exemplary embodiment of the present disclosure, a groove is formed on the sidewall of the ceramic base, and a sealing ring is disposed in the groove.

[0012] According to an exemplary embodiment of the present disclosure, a groove is formed in the end face of the ceramic base at the end away from the ceramic diaphragm, and a sealing ring is disposed in the groove.

[0013] According to an exemplary embodiment of the present disclosure, a mounting groove is formed on the ceramic base, and the pressure sensor is mounted to the pressure-to-be-measured component through the mounting groove.

[0014] According to an exemplary embodiment of the present disclosure, a mounting groove is formed on the cover, and the pressure sensor is mounted to the pressure-to-be-measured component through the mounting groove.

[0015] According to another aspect of this disclosure, a pressure interface for a pressure sensor is also provided, the pressure interface comprising: a cylindrical ceramic base; and a ceramic diaphragm disposed at one end of the ceramic base, wherein the ceramic base and the ceramic diaphragm are integrally formed.

[0016] The pressure sensor and its pressure interface described in the foregoing embodiments of this disclosure utilize an integrated ceramic base and ceramic diaphragm, eliminating the need for additional assembly and sealing, eliminating the risk of leakage, and reducing cost. Furthermore, since the pressure sensor is made entirely of ceramic material in contact with the pressure medium, it can be applied to corrosive pressure media and dialysis applications. Additionally, the surface roughness and cleanliness of the sintered pressure interface meet requirements, eliminating the need for sandblasting, cleaning, or heat treatment. Moreover, the extremely low electrical conductivity of the ceramic material solves the problem of low insulation and dielectric strength between the strain gauge and the ceramic diaphragm.

[0017] Other objects and advantages of this disclosure will become apparent from the following description of the disclosure with reference to the accompanying drawings, and will help to provide a comprehensive understanding of the disclosure. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a pressure sensor according to a first exemplary embodiment of the present disclosure;

[0019] Figure 2 yes Figure 1 A cross-sectional view of the pressure sensor shown;

[0020] Figure 3 This is a schematic diagram of the structure of a pressure sensor according to a second exemplary embodiment of the present disclosure; and

[0021] Figure 4 yes Figure 3 A partial cross-sectional view of the pressure sensor shown. Detailed Implementation

[0022] While this disclosure will be fully described with reference to the accompanying drawings containing preferred embodiments, it should be understood before this description that those skilled in the art can modify the disclosure described herein to obtain the technical effects of this disclosure. Therefore, it should be understood that the above description is a broad disclosure to those skilled in the art and is not intended to limit the exemplary embodiments described herein.

[0023] Furthermore, in the following detailed description, numerous specific details are set forth for ease of explanation to provide a thorough understanding of the embodiments disclosed herein. However, it will be apparent that one or more embodiments may be practiced without these specific details. In other instances, well-known structures and apparatuses are illustrated to simplify the figures.

[0024] According to a general inventive concept of this disclosure, a pressure sensor is provided. The pressure sensor includes: a pressure interface comprising a cylindrical ceramic base and a ceramic diaphragm disposed at one end of the ceramic base; and a strain gauge connected to the ceramic diaphragm, wherein the ceramic base and the ceramic diaphragm are integrally formed.

[0025] According to another general inventive concept of this disclosure, a pressure interface for a pressure sensor is provided, the pressure interface comprising a cylindrical ceramic base; and a ceramic diaphragm disposed at one end of the ceramic base; wherein the ceramic base and the ceramic diaphragm are integrally formed.

[0026] First Embodiment

[0027] Figure 1 This is a schematic diagram of the structure of a pressure sensor according to a first exemplary embodiment of the present disclosure; and Figure 2 yes Figure 1 The pressure sensor shown is a cross-sectional view.

[0028] like Figure 1 and Figure 2As shown, a pressure sensor according to an exemplary embodiment of this disclosure includes a pressure interface 10 and a strain gauge 20. The pressure interface 10 includes a ceramic base 11 and a ceramic diaphragm 12. The ceramic base 11 is generally cylindrical, and the ceramic diaphragm 12 is disposed 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 the cavity of the ceramic base 11 through the open end of the ceramic base 11, the ceramic diaphragm 12 deforms. The magnitude of the deformation is proportional to the pressure of the pressure medium to be measured. When the ceramic diaphragm 12 deforms, it causes the strain gauge 20 to deform as the ceramic diaphragm 12 deforms, thereby causing a change in the resistance of the strain gauge 20. The pressure of the pressure medium to be measured can be obtained by measuring the change in the resistance of the strain gauge 20. In this embodiment, the ceramic base 11 and the ceramic diaphragm 12 of the pressure interface 10 are integrally formed, for example, by sintering using a mold. Since the ceramic base 11 and ceramic diaphragm 12 of the pressure interface 10 are integrally formed, no additional assembly and sealing are required, eliminating the risk of leakage, while also reducing cost and labor time. Furthermore, because the pressure sensor is made entirely of ceramic material in contact with the pressure medium, it can be applied to corrosive pressure media and dialysis applications. In addition, the surface roughness and cleanliness of the pressure interface 10, after sintering, meet the requirements, eliminating the need for sandblasting, cleaning, or heat treatment. Moreover, the extremely low electrical conductivity of the ceramic material solves the problem of low insulation and dielectric strength between the strain gauge 20 and the ceramic diaphragm 12.

[0029] According to an exemplary embodiment of this disclosure, such as Figure 2 As shown, the strain gauge 20 is bonded to the ceramic diaphragm 12 after the glass is melted using a glass micro-melting process. Since the thermal expansion coefficients of glass and ceramic are similar, the strain of the strain gauge 20 is less affected by temperature changes, resulting in high thermal stability and thus improving the accuracy of the pressure sensor measurement.

[0030] According to an exemplary embodiment of this disclosure, such as Figure 2 As shown, the strain gauge 20 is made of semiconductor material, which can improve the sensitivity of the pressure sensor, for example, reaching above 20mV / V, and simplifies subsequent signal processing, resulting in higher accuracy. It should be noted that in some other embodiments of this disclosure, the strain gauge 20 may also be made of other materials, such as ceramic materials.

[0031] According to an exemplary embodiment of this disclosure, such as Figure 1 and 2As shown, the pressure sensor also includes a cover 30 that covers the pressure port 10. Specifically, in this embodiment, a radially outwardly extending flange 15 is formed on the ceramic base 11, and the cover 30 is attached to the flange 15. It should be noted that in some other embodiments not shown in this disclosure, the cover 30 can also be installed on the pressure port 10 in other ways, such as snap-fit ​​connection, bolt connection, etc.

[0032] According to an exemplary embodiment of this disclosure, such as Figure 2 As shown, the pressure sensor also includes a circuit board 60 located on the ceramic diaphragm 12. The circuit board 60 is electrically connected to the strain gauge 20 via a binding wire 70 to process the resistance change signal of the strain gauge 20. The circuit board 60 can be, for example, a flexible circuit board or a rigid circuit board. Specifically, in this embodiment, the circuit board 60 has a through hole 61 at its center, wherein the strain gauge 20 is attached to the ceramic diaphragm 12 at a position corresponding to the through hole 61, thus providing a certain degree of protection for the strain gauge 20.

[0033] According to an exemplary embodiment of this disclosure, such as Figure 1 and 2 As shown, the cable connected to the circuit board 60 is attached to the circuit board 60 and led out through the cable hole 31 opened on the cover 30.

[0034] According to an exemplary embodiment of this disclosure, such as Figure 2 As shown, a groove 14 is formed on the side wall of the ceramic base 11, and a sealing ring 50 is provided in the groove 14 to prevent leakage of the pressure medium to be tested, thereby improving the sealing effect.

[0035] According to an exemplary embodiment of this disclosure, such as Figure 2 As shown, a mounting groove 13 is formed on the outer wall of the ceramic base 11, through which the pressure sensor is mounted to the pressure-measuring component (not shown). For example, it can be mounted by passing two pins through the mounting groove 13 of the pressure interface 10.

[0036] Second Embodiment

[0037] Figure 3 This is a schematic diagram of the structure of a pressure sensor according to a first exemplary embodiment of the present disclosure; and Figure 4 yes Figure 3 A partial cross-sectional view of the pressure sensor shown.

[0038] The pressure sensor according to the second embodiment of this disclosure differs from the pressure sensor according to the first embodiment of this disclosure in the mounting position of the pressure sensor's cover and sealing ring.

[0039] like Figure 3and Figure 4 As shown, a groove 13 is formed on the end face of the ceramic base 11 away from the ceramic diaphragm 12. A sealing ring 50 is provided in the groove to prevent leakage of the pressure medium to be measured, thereby improving the sealing effect of the pressure sensor.

[0040] like Figure 3 and Figure 4 As shown, a mounting groove 32 is formed on the cover 30 to replace the mounting groove 13 on the ceramic base 11 of the pressure port according to the first embodiment of the present disclosure. In this embodiment, the pressure sensor is mounted to the pressure-to-be-tested component (not shown) through the mounting groove 32 on the cover 30.

[0041] According to another aspect of this disclosure, a pressure interface 10 for a pressure sensor is also provided, which can be the pressure interface 10 described above. Specifically, the pressure interface 10 includes a ceramic base 11 and a ceramic diaphragm 12. The ceramic base 11 is generally cylindrical, and the ceramic diaphragm 12 is disposed at one end of the ceramic base 11. The ceramic base 11 and the ceramic diaphragm 12 of the pressure interface 10 are integrally formed, for example, by sintering using a mold. Since the ceramic base 11 and the ceramic diaphragm 12 of the pressure interface 10 are integrally formed, no additional assembly and sealing are required, and there is no risk of leakage. Furthermore, the cost and labor time are low. Moreover, since the pressure sensor is made entirely of ceramic material in contact with the pressure medium, it can be applied to corrosive pressure media and dialysis, etc.

[0042] Those skilled in the art will understand that the embodiments described above are exemplary and can be improved upon. The structures described in the various embodiments can be freely combined without causing any conflict in structure or principle.

[0043] Although this disclosure has been described in conjunction with the accompanying drawings, the embodiments disclosed in the drawings are intended to illustrate preferred embodiments of this disclosure and should not be construed as a limitation thereof.

[0044] While some embodiments of the present general inventive concept have been shown and described, those skilled in the art will understand that changes may be made to these embodiments without departing from the principles and spirit of the present general inventive concept, the scope of which is defined by the claims and their equivalents.

[0045] It should be noted that the word "comprising" does not exclude other elements or steps, and the words "a" or "an" do not exclude multiple. Furthermore, any element reference numerals in the claims should not be construed as limiting the scope of this disclosure.

Claims

1. A pressure sensor, the pressure sensor comprising: A pressure port (10), the pressure port (10) comprising a cylindrical ceramic base (11) and a ceramic diaphragm (12) disposed at one end of the ceramic base (11); and Strain gauge (20), the strain gauge is connected to the ceramic diaphragm. The ceramic base (11) and the ceramic diaphragm (12) are integrally formed.

2. The pressure sensor according to claim 1, wherein, The strain gauge (20) is attached to the ceramic diaphragm (12) via a glass micro-dissolution process.

3. The pressure sensor according to claim 1, wherein, The strain gauge (20) is made of semiconductor material.

4. The pressure sensor according to claim 1, wherein, It also includes a cover (30) provided on one end of the pressure port (10) where the ceramic diaphragm (12) is located.

5. The pressure sensor according to claim 4, wherein, A radially outwardly extending flange (15) is formed on the ceramic base (11), and the cover (30) is attached to the flange.

6. The pressure sensor according to claim 4, wherein, The pressure sensor also includes a circuit board (60) located on the ceramic diaphragm (12), the circuit board (60) being electrically connected to the strain gauge (20) via a wire (70).

7. The pressure sensor according to claim 6, wherein, The cable (40) connected to the circuit board (60) is attached to the circuit board (60) and led out through the wire hole (31) opened on the cover (30).

8. The pressure sensor according to claim 4, wherein, A groove (14) is formed on the side wall of the ceramic base (11), and a sealing ring (50) is provided in the groove.

9. The pressure sensor according to claim 4, wherein, A groove (14) is formed in the end face of the ceramic base (11) away from the ceramic diaphragm (12), and a sealing ring (50) is provided in the groove.

10. The pressure sensor according to any one of claims 1 to 9, wherein, A mounting groove (13) is formed on the ceramic base (11), and the pressure sensor is mounted to the pressure-testing component through the mounting groove (13).

11. The pressure sensor according to any one of claims 4 to 9, wherein, The cover (30) has a mounting groove (32) formed thereon, and the pressure sensor is mounted to the pressure-testing component through the mounting groove (32).

12. A pressure interface for a pressure sensor, the pressure interface comprising: Cylindrical ceramic base (11); as well as A ceramic diaphragm (12) is disposed at one end of the ceramic substrate; The ceramic base and the ceramic diaphragm are integrally formed.

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