High-pressure-resistant pressure sensor and manufacturing method

Abstract

The invention discloses a high-pressure-resistant pressure sensor and a manufacturing method, and belongs to the technical field of pressure sensors, and the high-pressure-resistant pressure sensor comprises a sintering base with an oil filling hole, a corrugated diaphragm connected with the sintering base, a ceramic gasket connected with the sintering base, protection ceramic connected with the ceramic gasket, and a conductive part connected with the ceramic gasket. An oil filling hole is formed in the sintering base, the conductive part is arranged in the oil filling hole, the pressure sensing element is connected with the conductive part, the jackscrew is connected with the sintering base and located in the oil filling hole, the sealing ball is connected with the jackscrew, a cavity is defined by the sintering base and the corrugated diaphragm, the cavity is communicated with the oil filling hole, and the protection ceramic is located between the ceramic gasket and the corrugated diaphragm. The sealing ball is located in the oil filling hole and used for sealing the oil filling hole, the ceramic gasket is located between the pressure sensing element and the protective ceramic, and the ceramic gasket, the protective ceramic, the conductive part and the pressure sensing element are located in the cavity. The technical effects of improving the voltage endurance capability and improving the stability are achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of pressure sensors, and particularly relates to a high-pressure resistant pressure sensor and a manufacturing method thereof. Background Art

[0002] Pressure sensors are widely used in fields such as aerospace, industrial control, and instrumentation. A pressure sensor can convert an external pressure signal into an electrical signal to achieve accurate measurement of the external pressure. When a pressure sensor is applied during the flight of an aircraft, real-time monitoring of pressure values such as the brake pressure and emergency nitrogen cylinder pressure in the aircraft's pipelines places more stringent requirements on the stability and high-pressure resistance of the sensor. In the prior art, when a pressure sensor faces extreme high-pressure conditions, the structural strength and sealing performance of the pressure sensor are difficult to meet the requirements, easily leading to inaccurate measurement or equipment damage, and insufficient pressure resistance. The stability of the pressure sensor is not good under complex working conditions such as temperature changes and vibrations, which will reduce the reliability of the measurement results, and the stability of the pressure sensor is poor.

[0003] Therefore, it is necessary to provide a new technical solution to solve the above technical problems. Summary of the Invention

[0004] The technical problems to be solved by the present invention are the technical problems of insufficient pressure resistance and poor stability.

[0005] To solve the above technical problems, the present invention provides a high-pressure resistant pressure sensor. The high-pressure resistant pressure sensor includes a sintered base having an oil filling hole, a corrugated diaphragm connected to the sintered base, a ceramic gasket connected to the sintered base, a protective ceramic connected to the ceramic gasket, a conductive member connected to the ceramic gasket, a pressure sensing element connected to the conductive member, a setscrew connected to the sintered base and located in the oil filling hole, and a sealing ball connected to the setscrew. The sintered base and the corrugated diaphragm enclose a cavity, the cavity is communicated with the oil filling hole, the protective ceramic is located between the ceramic gasket and the corrugated diaphragm, the sealing ball is located in the oil filling hole, the sealing ball is used to seal the oil filling hole, the ceramic gasket is located between the pressure sensing element and the protective ceramic, wherein the ceramic gasket, the protective ceramic, the conductive member, and the pressure sensing element are located in the cavity.

[0006] Optionally, the high-pressure resistant pressure sensor further includes a compression ring, the compression ring is laser welded to the sintered base, and the corrugated diaphragm is located between the compression ring and the sintered base.

[0007] Optionally, the corrugated diaphragm is laser welded to the sintered base, the pressure sensing element is fixed to the sintered base by a patch glue, the conductive member is a gold wire, and glue is provided between the conductive member and the ceramic gasket.

[0008] Optionally, the ceramic gasket is fixed to the sintered base by a patch glue, and the protective ceramic is fixed to the ceramic gasket by the patch glue.

[0009] Optionally, the setscrew is in threaded connection with the sintered base, and the sealing ball is in interference fit connection with the sintered base.

[0010] Optionally, the high-pressure resistant pressure sensor further includes a lead wire connected to the pressure sensing element, and at least a part of the lead wire is located outside the cavity.

[0011] Optionally, the high-pressure resistant pressure sensor further includes an adhesive filled in the oil filling hole, the adhesive is located between the setscrew and the sintered base, and the adhesive includes an epoxy resin glue.

[0012] According to another aspect of the present invention, the present invention further provides a method for manufacturing a high-pressure resistant pressure sensor. The method for manufacturing the high-pressure resistant pressure sensor includes: welding a protective ceramic to a ceramic gasket, and bonding a conductive part to the ceramic gasket; fixing a pressure sensing element to the sintered base by a patch glue, and connecting the pressure sensing element to the conductive part; welding a corrugated diaphragm and a pressing ring to the sintered base respectively, the corrugated diaphragm is located between the pressing ring and the sintered base, so as to enclose a cavity through the sintered base and the corrugated diaphragm, and the cavity is communicated with an oil filling hole located in the sintered base; filling a pressure medium into the cavity through the oil filling hole, and the ceramic gasket, the protective ceramic, the conductive part and the pressure sensing element are located in the cavity; driving a setscrew in threaded connection with the sintered base and located in the oil filling hole to drive a sealing ball connected to the setscrew to seal the oil filling hole.

[0013] Optionally, welding the protective ceramic to the ceramic gasket includes laser welding the protective ceramic and the ceramic gasket by using a laser; bonding the conductive part to the ceramic gasket includes arranging glue between the conductive part and the ceramic gasket, and the pressure sensing element is bonded to the ceramic gasket through the glue; welding the corrugated diaphragm and the pressing ring to the sintered base respectively includes laser welding the corrugated diaphragm and the sintered base by using the laser, and laser welding the pressing ring and the sintered base by using the laser.

[0014] Optionally, the method for manufacturing the high-pressure resistant pressure sensor further includes filling an adhesive into the oil filling hole, and the adhesive is located between the setscrew and the sintered base, the adhesive includes an epoxy resin glue, and the pressure medium includes silicone oil.

[0015] Beneficial effects:

[0016] The present invention provides a high-pressure resistant pressure sensor. The corrugated diaphragm is connected to the sintered base, and the sintered base and the corrugated diaphragm enclose a cavity. The cavity is in communication with the oil filling hole located in the sintered base. The ceramic gasket is connected to the sintered base, the protective ceramic is connected to the ceramic gasket, and the protective ceramic is located between the ceramic gasket and the corrugated diaphragm. The conductive part is connected to the ceramic gasket, the pressure sensing element is connected to the conductive part, and the ceramic gasket is located between the pressure sensing element and the protective ceramic. Among them, the ceramic gasket, the protective ceramic, the conductive part and the pressure sensing element are located inside the cavity. The setscrew is connected to the sintered base and is located inside the oil filling hole. The sealing ball is connected to the setscrew and is located inside the oil filling hole. The sealing ball is used to seal the oil filling hole. In this way, a cavity structure capable of withstanding a certain pressure is formed by the combination of the sintered base and the corrugated diaphragm, and silicone oil can enter the inside of the cavity from the oil filling hole. When an external pressure acts on the corrugated diaphragm, the pressure is transmitted to the silicone oil inside the cavity through the corrugated diaphragm. The silicone oil evenly distributes the pressure and conducts it to the pressure sensing element. The pressure sensing element senses the pressure change and converts the pressure signal into an electrical signal. The conductive part is used to transmit the electrical signal. The ceramic gasket can reduce the volume of the internal cavity of the pressure sensor, which is beneficial to reducing the influence of the thermal expansion coefficient of the silicone oil in the cavity on the encapsulated pressure sensing element and improving the stability of the sensor. And the protective ceramic can effectively avoid the short-circuit risk caused by the direct contact between the corrugated diaphragm and the gold wire under overpressure conditions, realizing overpressure protection of the sensor. At the same time, the effective sealing of the oil filling hole under high pressure is realized through the cooperation of the sealing ball and the setscrew, improving the pressure resistance of the sensor. Thus, the technical effects of improving the pressure resistance and enhancing the stability are achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0018] Figure 1 FIG. is a schematic structural diagram of a high-pressure resistant pressure sensor provided by an embodiment of the present invention.

[0019] Figure 2 FIG. is a schematic structural diagram of a sintered base in a high-pressure resistant pressure sensor provided by an embodiment of the present invention.

[0020] Figure 3 FIG. is a flowchart of a manufacturing method of a high-pressure resistant pressure sensor provided by an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0021] The embodiments of the present application will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary only for explaining the present application and should not be construed as limiting the present application.

[0022] In order to enable those skilled in the art to better understand the solution of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative efforts belong to the scope of protection of the present application.

[0023] In the embodiments of the present application, "at least one" means one or more; "a plurality" means two or more. In the description of the present application, terms such as "first", "second", "third", etc. are only used for the purpose of distinguishing descriptions and should not be construed as indicating or implying relative importance, nor as indicating or implying order.

[0024] The reference to "an embodiment" or "some embodiments" etc. in this specification means that a specific feature, structure, or characteristic described in connection with the embodiment is included in one or more embodiments of the present application. Thus, the terms "include", "comprise", "have" and their variants in this specification all mean "including but not limited to", unless otherwise specifically emphasized in other ways. It should be noted that in the embodiments of the present application, "and / or" describes the association relationship of associated objects and means that three relationships can exist. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone.

[0025] It should be pointed out that in the embodiments of the present invention, when a component is referred to as "fixed to" another component, it can be directly on the other component or there may also be an intermediate component. When a component is considered to be "connected to" another component, it can be directly connected to the other component or there may be an intermediate component at the same time. When a component is considered to be "disposed on" another component, it can be directly disposed on the other component or there may be an intermediate component at the same time. At the same time, in the embodiments of the present application, "connection" can also be understood as electrical connection, and the connection of two electrical components can be a direct or indirect connection between the two electrical components. For example, when A is connected to B, it can be a direct connection between A and B or an indirect connection between A and B through one or more other electrical components. The terms "vertical", "horizontal", "left", "right" and similar expressions used in the embodiments of the present invention are only for illustrative purposes and are not intended to limit the present invention.

[0026] A high-pressure resistant pressure sensor provided in Embodiment 1 of the present invention, please refer to Figures 1 to 2 as shown in Figure 1 which is a schematic structural diagram of a high-pressure resistant pressure sensor provided in an embodiment of the present invention, Figure 2 and is a schematic structural diagram of a sintered base 1 in a high-pressure resistant pressure sensor provided in an embodiment of the present invention. A high-pressure resistant pressure sensor provided in an embodiment of the present invention includes a sintered base 1, a corrugated diaphragm 2, a ceramic gasket 3, a protective ceramic 4, a conductive member 5, a pressure sensing element 6, a set screw 7, and a sealing ball 8. The sintered base 1 has an oil filling hole 11. The corrugated diaphragm 2 is connected to the sintered base 1. The ceramic gasket 3 is connected to the sintered base 1. The protective ceramic 4 is connected to the ceramic gasket 3. The conductive member 5 is connected to the ceramic gasket 3. The pressure sensing element 6 is connected to the conductive member 5. The set screw 7 is connected to the sintered base 1, and the set screw 7 is located inside the oil filling hole 11. The sealing ball 8 is connected to the set screw 7. A cavity 12 is formed by enclosing the sintered base 1 and the corrugated diaphragm 2. The cavity 12 is in communication with the oil filling hole 11. The protective ceramic 4 is located between the ceramic gasket 3 and the corrugated diaphragm 2. The sealing ball 8 is located inside the oil filling hole 11. The sealing ball 8 is used to seal the oil filling hole 11. The ceramic gasket 3 is located between the pressure sensing element 6 and the protective ceramic 4, wherein the ceramic gasket 3, the protective ceramic 4, the conductive member 5, and the pressure sensing element 6 are respectively located inside the cavity 12.

[0027] Wherein, inside the cavity 12 formed by enclosing the sintered base 1 and the corrugated diaphragm 2, there is a space for accommodating the ceramic gasket 3, the protective ceramic 4, the conductive member 5, the pressure sensing element 6, and silicone oil. The inner part of the pore channel of the oil filling hole 11 can be in communication with the outside and the inside of the cavity 12 respectively, so that the silicone oil is filled into the cavity 12 from the inner part of the pore channel of the oil filling hole 11. The inner part of the pore channel of the oil filling hole 11 has a space for accommodating the sealing ball 8 and the set screw 7. The set screw 7 is connected to the sintered base 1. For example, there is a thread provided on the inner wall of the pore channel inside the oil filling hole 11, and the set screw 7 located inside the pore channel of the oil filling hole 11 is threadedly connected to the inner wall thread. By installing the set screw 7 into the pore channel of the oil filling hole 11, the set screw 7 drives the sealing ball 8 to seal the inner part of the pore channel of the oil filling hole 11, preventing the silicone oil filled into the cavity 12 from overflowing from the inner part of the pore channel of the oil filling hole 11. In addition, the part of the pore channel of the oil filling hole 11 close to the sealing ball 8 can be in the shape of a conical surface, that is, it is gradually expanding along the direction close to the sealing ball 8, so that the sealing ball 8 can fit on the inner part of the pore channel of the conical surface of the oil filling hole 11 to achieve a firm seal of the oil filling hole 11.

[0028] Among them, the corrugated diaphragm 2 can have high elasticity and good sealing performance. The corrugated diaphragm 2 can respond to external pressure changes and transmit the pressure to the silicone oil located inside the cavity 12. The protective ceramic 4 layer is located between the ceramic gasket 3 and the corrugated diaphragm 2. As a barrier, the protective ceramic 4 can effectively prevent the corrugated diaphragm 2 from directly contacting the gold wire under extreme pressure, and can avoid the risk of short circuit. The conductive member 5 can export the electrical signal converted by the pressure sensing element 6 to ensure the accurate transmission of the signal. The pressure sensing element 6 can accurately sense the pressure change transmitted by the silicone oil located inside the cavity 12 and convert the pressure change into a corresponding electrical signal.

[0029] In this embodiment, the corrugated diaphragm 2 is connected to the sintered base 1. The sintered base 1 and the corrugated diaphragm 2 enclose to form a cavity 12. The cavity 12 is in communication with the oil filling hole 11 located on the sintered base 1. The ceramic gasket 3 is connected to the sintered base 1, the protective ceramic 4 is connected to the ceramic gasket 3, and the protective ceramic 4 is located between the ceramic gasket 3 and the corrugated diaphragm 2. The conductive member 5 is connected to the ceramic gasket 3, and the pressure sensing element 6 is connected to the conductive member 5. The ceramic gasket 3 is located between the pressure sensing element 6 and the protective ceramic 4. Among them, the ceramic gasket 3, the protective ceramic 4, the conductive member 5 and the pressure sensing element 6 are located inside the cavity 12. The setscrew 7 is connected to the sintered base 1, the setscrew 7 is located inside the oil filling hole 11, the sealing ball 8 is connected to the setscrew 7, the sealing ball 8 is located inside the oil filling hole 11, and the sealing ball 8 is used to seal the oil filling hole 11. In this way, a cavity 12 structure capable of withstanding a certain pressure is formed by the combination of the sintered base 1 and the corrugated diaphragm 2, and the silicone oil can enter the inside of the cavity 12 from the oil filling hole 11. When an external pressure acts on the corrugated diaphragm 2, the pressure is transmitted to the silicone oil inside the cavity 12 through the corrugated diaphragm 2. The silicone oil evenly distributes the pressure and conducts it to the pressure sensing element 6. The pressure sensing element 6 senses the pressure change and converts the pressure signal into an electrical signal. The conductive member 5 is used to transmit the electrical signal. The volume of the internal cavity 12 of the pressure sensor can be reduced by the ceramic gasket 3, which is beneficial to reducing the influence of the thermal expansion coefficient of the silicone oil inside the cavity 12 on the encapsulated pressure sensing element 6 and improving the stability of the sensor. And the protective ceramic 4 can effectively avoid the short circuit risk caused by the direct contact between the corrugated diaphragm 2 and the gold wire under overpressure, realizing overpressure protection of the sensor. At the same time, the effective sealing of the oil filling hole 11 under high pressure is realized through the cooperation of the sealing ball 8 and the setscrew 7, improving the pressure resistance of the sensor. Thus, the technical effects of improving the pressure resistance and enhancing the stability are achieved.

[0030] As an implementation manner, a high-pressure resistant pressure sensor provided by an embodiment of the present invention further includes a compression ring 9, the compression ring 9 is laser welded to the sintered base 1, and the corrugated diaphragm 2 is located between the compression ring 9 and the sintered base 1. The compression ring 9 can enhance the connection strength between the sintered base 1 and the corrugated diaphragm 2, making the cavity 12 structure more stable and capable of withstanding higher pressures. At the same time, the compression ring 9 is tightly connected to the sintered base 1 by laser welding, which can ensure good sealing performance, prevent the leakage of silicone oil or other media, make the sensor more stable and reliable in a high-pressure environment, and is beneficial to extending the service life of the sensor.

[0031] In some implementation manners, the corrugated diaphragm 2 is laser welded to the sintered base 1, the pressure-sensitive element 6 is fixed to the sintered base 1 by a patch glue, the conductive member 5 is a gold wire, and glue is provided between the conductive member 5 and the ceramic gasket 3. Laser welding can ensure a firm connection between the corrugated diaphragm 2 and the sintered base 1, improving the overall strength and sealing performance of the sensor. The use of the patch glue can simplify the installation process of the pressure-sensitive element 6, and at the same time provide a good fixing effect, preventing the displacement or damage of the pressure-sensitive element 6 under high pressure. The gold wire as the conductive member 5 has good electrical conductivity and mechanical strength, and can meet the signal transmission requirements in a high-pressure environment. In addition, the conductive member 5 can also include aluminum or platinum materials. The glue between the conductive member 5 and the ceramic gasket 3 not only provides an additional fixing effect, but also can play an insulating and protective role, preventing electrical failures.

[0032] In some implementation manners, the ceramic gasket 3 is fixed to the sintered base 1 by a patch glue, and the protective ceramic 4 is fixed to the ceramic gasket 3 by a patch glue. By using the patch glue, the installation process of the ceramic gasket 3 and the protective ceramic 4 can be simplified, and at the same time a reliable fixing effect can be provided, which not only ensures the precise alignment between components, but also can improve the overall stability and durability of the sensor. In addition, the patch glue also has a certain buffering effect, which can absorb part of the pressure fluctuation, and is beneficial to improving the measurement accuracy and stability of the sensor.

[0033] In some implementation manners, the setscrew 7 is threadedly connected to the sintered base 1. The threaded connection provides a firm connection between the setscrew 7 and the sintered base 1, enabling the setscrew 7 to withstand large tensile and compressive forces, and at the same time facilitating installation and disassembly. The sealing ball 8 is connected to the sintered base 1 by an interference fit. The sealing ball 8 can include a steel ball. The interference fit connection can ensure a tight fit between the sealing ball 8 and the sintered base 1, preventing the leakage of silicone oil or other media, and is beneficial to improving the pressure resistance and sealing performance of the sensor, making the sensor more stable and reliable in a high-pressure environment.

[0034] In some embodiments, a high-pressure resistant pressure sensor provided by an embodiment of the present invention further includes a lead wire 10. The lead wire 10 is connected to the pressure sensing element 6, and at least a part of the lead wire 10 is located outside the cavity 12. The lead wire 10 enables the sensor to be connected to an external circuit, realizes signal transmission and reception, and also enables the sensor to be more conveniently integrated into various measurement systems, improving the application flexibility and practicality of the sensor. At the same time, at least a part of the lead wire 10 is located outside the cavity 12, which also avoids the influence of the high-temperature and high-pressure environment on the lead wire 10. The lead wire 10 located inside the cavity 12 can be connected to the pressure sensing element 6 or the conductive member 5, and the lead wire 10 located outside the cavity 12 can be connected to an external circuit. The pressure change is sensed by the pressure sensing element 6 and the pressure signal is converted into an electrical signal and transmitted to the outside through the lead wire 10, realizing the improvement of the stability and reliability of the sensor.

[0035] In some embodiments, the high-pressure resistant pressure sensor further includes an adhesive. The adhesive is filled inside the oil filling hole 11. The adhesive is located between the setscrew 7 and the sintered base 1. The adhesive includes an epoxy resin adhesive material. After filling the epoxy resin adhesive in the oil filling hole 11 as the adhesive, due to the excellent sealing performance of the epoxy resin adhesive, it can further ensure the sealing performance of the oil filling hole 11 under high pressure, prevent the leakage of silicone oil or other media, and is beneficial to enhancing the pressure resistance and stability of the sensor. At the same time, the epoxy resin adhesive also has a certain strength and toughness, which can absorb and disperse the stress that may occur between the setscrew 7 and the sintered base 1 to a certain extent, reducing the risk of damage caused by stress concentration. And filling the epoxy resin adhesive in the oil filling hole 11 to fix the setscrew 7 can also prevent the loosening of the setscrew 7, improve the reliability of high-pressure resistant sealing, make the pressure sensor more stable and reliable in a high-pressure environment, and extend the service life of the sensor.

[0036] To describe in detail a manufacturing method of a high-pressure resistant pressure sensor provided by the present invention, the above-mentioned Embodiment 1 describes a high-pressure resistant pressure sensor in detail. Based on the same inventive concept, the present application also provides a manufacturing method of a high-pressure resistant pressure sensor. For details, see Embodiment 2.

[0037] Please refer to Figure 3 , Figure 3 which is a flowchart of a manufacturing method of a high-pressure resistant pressure sensor provided by an embodiment of the present invention. Embodiment 2 of the present invention provides a manufacturing method of a high-pressure resistant pressure sensor, including the following steps:

[0038] Step S100: Weld the protective ceramic 4 to the ceramic gasket 3 and bond the conductive member 5 to the ceramic gasket 3;

[0039] Step S200: Fix the pressure sensing element 6 to the sintered base 1 through the patch glue and connect the pressure sensing element 6 to the conductive member 5;

[0040] Step S300: Weld the corrugated diaphragm 2 and the pressure ring 9 to the sintered base 1 respectively. The corrugated diaphragm 2 is located between the pressure ring 9 and the sintered base 1, so as to form a cavity 12 by enclosing the sintered base 1 and the corrugated diaphragm 2. The cavity 12 communicates with the oil filling hole 11 located on the sintered base 1.

[0041] Step S400: Fill the cavity 12 with a pressure medium through the oil filling hole 11. The ceramic gasket 3, the protective ceramic 4, the conductive member 5 and the pressure sensing element 6 are located in the cavity 12.

[0042] Step S500: Drive the setscrew 7 that is threadedly connected to the sintered base 1 and located in the oil filling hole 11 to drive the sealing ball 8 connected to the setscrew 7 to seal the oil filling hole 11.

[0043] In some embodiments, welding the protective ceramic 4 to the ceramic gasket 3 includes using a laser to perform laser welding on the protective ceramic 4 and the ceramic gasket 3. In the manufacturing method of the high-pressure resistant pressure sensor provided in the second embodiment of the present invention, the laser may refer to a device that can generate high-intensity coherent light beams, that is, a laser. Laser welding is a precise welding method that uses a laser beam as a heat source to melt the workpiece and achieve connection. Bonding the conductive member 5 to the ceramic gasket 3 includes setting glue between the conductive member 5 and the ceramic gasket 3, and the pressure sensing element 6 is bonded to the ceramic gasket 3 through the glue. Welding the corrugated diaphragm 2 and the pressure ring 9 to the sintered base 1 respectively includes using the laser to perform laser welding on the corrugated diaphragm 2 and the sintered base 1, and using the laser to perform laser welding on the pressure ring 9 and the sintered base 1.

[0044] In some embodiments, the manufacturing method of the high-pressure resistant pressure sensor further includes filling an adhesive into the oil filling hole 11, and the adhesive is located between the setscrew 7 and the sintered base 1. The adhesive includes epoxy resin glue, and the pressure medium includes silicone oil.

[0045] The present invention provides a method for manufacturing a high-pressure resistant pressure sensor. The method includes welding a protective ceramic 4 to a ceramic gasket 3 and bonding a conductive member 5 to the ceramic gasket 3; fixing a pressure sensing element 6 to a sintered base 1 by means of a patch glue and connecting the pressure sensing element 6 to the conductive member 5; welding a corrugated diaphragm 2 and a retaining ring 9 to the sintered base 1 respectively, with the corrugated diaphragm 2 positioned between the retaining ring 9 and the sintered base 1, so as to form a cavity 12 by enclosing the sintered base 1 and the corrugated diaphragm 2, and the cavity 12 communicating with an oil filling hole 11 located in the sintered base 1; filling a pressure medium into the cavity 12 through the oil filling hole 11, with the ceramic gasket 3, the protective ceramic 4, the conductive member 5 and the pressure sensing element 6 located in the cavity 12; driving a setscrew 7 threadedly connected to the sintered base 1 and located in the oil filling hole 11 to drive a sealing ball 8 connected to the setscrew 7 to seal the oil filling hole 11. In this way, a cavity 12 structure capable of withstanding a certain pressure is formed by the combination of the sintered base 1 and the corrugated diaphragm 2, and silicone oil can enter the interior of the cavity 12 from the oil filling hole 11. When an external pressure acts on the corrugated diaphragm 2, the pressure is transmitted to the silicone oil in the cavity 12 through the corrugated diaphragm 2. The silicone oil evenly distributes the pressure and conducts it to the pressure sensing element 6. The pressure sensing element 6 senses the pressure change and converts the pressure signal into an electrical signal, and the conductive member 5 is used to transmit the electrical signal. The ceramic gasket 3 can reduce the volume of the internal cavity 12 of the pressure sensor, which is beneficial to reducing the influence of the thermal expansion coefficient of the silicone oil in the cavity 12 on the encapsulated pressure sensing element 6 and improving the stability of the sensor. Moreover, the protective ceramic 4 can effectively avoid the short-circuit risk caused by the direct contact between the corrugated diaphragm 2 and the gold wire under overpressure conditions, realizing overpressure protection for the sensor. At the same time, the effective sealing of the oil filling hole 11 under high pressure is achieved through the cooperation of the sealing ball 8 and the setscrew 7, enhancing the pressure resistance of the sensor. Thus, the technical effects of improving the pressure resistance and enhancing the stability are achieved.

[0046] Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solutions of the present invention rather than to limit them. Although the present invention has been described in detail with reference to the examples, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered by the scope of the claims of the present invention.

Claims

1. A high pressure resistant pressure sensor, characterized in that: The high-pressure resistant pressure sensor includes a sintered base with an oil-filling hole, a corrugated diaphragm connected to the sintered base, a ceramic gasket connected to the sintered base, a protective ceramic connected to the ceramic gasket, a conductive part connected to the ceramic gasket, a pressure-sensitive element connected to the conductive part, a top screw connected to the sintered base and located in the oil-filling hole, and a sealing ball connected to the top screw. The sintered base and the corrugated diaphragm enclose a cavity, which is connected to the oil-filling hole. The protective ceramic is located between the ceramic gasket and the corrugated diaphragm. The sealing ball is located in the oil-filling hole. The sealing ball is used to seal the oil-filling hole. The ceramic gasket is located between the pressure-sensitive element and the protective ceramic, wherein the ceramic gasket, the protective ceramic, the conductive part and the pressure-sensitive element are located in the cavity.

2. The high-pressure resistant pressure sensor according to claim 1, characterized in that: The high-pressure resistant pressure sensor further comprises a pressure ring, which is laser welded to the sintered base, and the corrugated diaphragm is located between the pressure ring and the sintered base.

3. The high-pressure resistant pressure sensor according to claim 1, characterized in that: The corrugated diaphragm is welded to the sintered base by laser, the pressure-sensitive element is fixed to the sintered base by patch adhesive, the conductive member is a gold wire, and glue is provided between the conductive member and the ceramic gasket.

4. The high-pressure resistant pressure sensor according to claim 1, characterized in that: The ceramic gasket is fixed to the sintered base by using patch adhesive, and the protective ceramic is fixed to the ceramic gasket by using patch adhesive.

5. The high-pressure resistant pressure sensor according to claim 1, characterized in that: The top screw is threadedly connected to the sintered base, and the sealing ball is connected to the sintered base by interference fit.

6. The high-pressure resistant pressure sensor according to claim 1, characterized in that: The high-pressure resistant pressure sensor further includes a lead wire connected to the pressure-sensitive element, and the lead wire is at least partially located outside the cavity.

7. The high-pressure resistant pressure sensor according to claim 1, characterized in that: The high-pressure resistant pressure sensor also includes an adhesive filled in the oil filling hole, the adhesive is located between the top screw and the sintered base, and the adhesive includes epoxy resin glue.

8. A method for manufacturing a high-pressure resistant pressure sensor, characterized in that: The method for manufacturing the high-pressure resistant pressure sensor comprises: Welding the protective ceramic to the ceramic gasket and bonding the conductive member to the ceramic gasket; Fixing the pressure-sensitive element to the sintered base by using patch adhesive, and connecting the pressure-sensitive element to the conductive member; Welding a corrugated diaphragm and a pressure ring to the sintered base respectively, wherein the corrugated diaphragm is located between the pressure ring and the sintered base, so that a cavity is formed by the sintered base and the corrugated diaphragm, and the cavity is connected to the oil filling hole located on the sintered base; Filling the pressure medium into the cavity through the oil filling hole, wherein the ceramic gasket, the protective ceramic, the conductive member and the pressure-sensitive element are located in the cavity; The top wire which is threadedly connected with the sintered base and located in the oil filling hole is driven to drive the sealing ball connected with the top wire to seal the oil filling hole.

9. The method for manufacturing a high-pressure resistant pressure sensor according to claim 8, characterized in that: The step of welding the protective ceramic to the ceramic gasket comprises performing laser welding on the protective ceramic and the ceramic gasket using a laser; the step of bonding the conductive member to the ceramic gasket comprises providing glue between the conductive member and the ceramic gasket, and the pressure-sensitive element is bonded to the ceramic gasket via the glue; the step of welding the corrugated diaphragm and the pressure ring to the sintered base respectively comprises performing laser welding on the corrugated diaphragm and the sintered base using the laser, and performing laser welding on the pressure ring and the sintered base using the laser.

10. The method for manufacturing a high-pressure resistant pressure sensor according to claim 8, characterized in that: The method for manufacturing a high-pressure resistant pressure sensor also includes filling an adhesive into the oil-filling hole, and the adhesive is located between the top screw and the sintered base, the adhesive includes epoxy resin glue, and the pressure medium includes silicone oil.

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