Pressure transmitter with high dielectric strength

Abstract

The application discloses a pressure transmitter with high insulation strength, and belongs to the technical field of pressure measuring equipment. The pressure transmitter comprises a shell, a pressure sensor, a signal processing circuit board, a pressure interface and an electrical interface. The pressure sensor is packaged by a metal sintered part and a glass insulator. The signal processing circuit board is installed through an insulating gasket. The internal cavity of the shell is integrally filled with epoxy resin glue and covers all internal components and wires. The signal processing circuit board is customized and cut. The minimum distance between the conductive circuit and the inner wall of the shell is greater than 2 mm. O-shaped sealing rings are arranged at key connection positions. Damping gaskets are arranged in the shell. Through multi-layer collaborative design, the insulation strength is improved to 1800VAC / 50Hz for 60s, the leakage current is less than 0.5mA, the anti-interference ability and environmental adaptability are significantly enhanced, the device can be stably applied to high-voltage, high-humidity and strong electromagnetic interference working conditions, and the fault-free operation time of the device is prolonged.

Description

Technical Field

[0001] This application belongs to the technical field of pressure measurement equipment, and specifically relates to a pressure transmitter with high insulation strength. Background Technology

[0002] A pressure transmitter is an instrument that converts physical pressure parameters into standard electrical signals. It is widely used in industrial process control, power systems, energy, and data center liquid cooling systems. In these applications, especially under harsh conditions of high pressure, high humidity, or strong electromagnetic interference, extremely high requirements are placed on the electrical insulation strength and electromagnetic compatibility of the transmitter.

[0003] Currently, common pressure transmitters typically use conventional epoxy resin or engineering plastics for sensor encapsulation and circuit insulation to meet basic insulation and electromagnetic compatibility requirements, with simple protective devices added to the circuitry. However, this existing technology has the following significant drawbacks: First, conventional insulating materials have limited overall resistivity and arc resistance, easily becoming weak points in insulation under long-term high electric fields or humid environments, leading to decreased insulation performance or even failure. This makes it difficult to improve the overall insulation strength of the transmitter, typically only achieving a level of approximately 500VAC / 50Hz for 60 seconds. Second, when facing complex electromagnetic interference in industrial environments, insufficient insulation design margins and a lack of systematic electromagnetic compatibility design result in limited protection effectiveness, easily leading to signal fluctuations or device damage, making it difficult to stably pass stringent electromagnetic compatibility certifications. Furthermore, existing improvement schemes are mostly isolated optimizations of sensors, circuits, or structures, failing to integrate and coordinate the design of the entire signal chain from sensor body insulation and printed circuit board layout insulation to system-level circuit protection, resulting in bottlenecks in system insulation strength and anti-interference capabilities that are difficult to overcome.

[0004] Therefore, there is an urgent need for a pressure transmitter that can comprehensively and synergistically improve insulation strength and electromagnetic compatibility to meet the extreme safety and reliability requirements of high-end applications such as liquid-cooled servers and power monitoring. Utility Model Content

[0005] The purpose of this application is to provide a pressure transmitter with high insulation strength. This addresses the problems mentioned in the background art, such as insufficient insulation material performance, isolated insulation and protection design leading to low insulation strength, susceptibility to moisture and electromagnetic interference, and difficulty in meeting the requirements of harsh operating conditions like high pressure and high humidity.

[0006] To achieve the above objectives, this application adopts the following technical solution: A pressure transmitter with high insulation strength includes a housing, a pressure sensor disposed inside the housing, and a signal processing circuit board. The pressure sensor has an encapsulation structure formed by a metal sintered component and a glass insulator. The signal processing circuit board is mounted and fixed using insulating pads; The internal cavity of the housing is completely encapsulated with epoxy resin, which covers the pressure sensor, the signal processing circuit board, and their connecting wires.

[0007] In one possible implementation, the glass insulator is welded and encapsulated within the sintered metal component, and the metal body of the pressure sensor is electrically isolated from the outside via the glass insulator.

[0008] In one possible implementation, the signal processing circuit board is a double-layer circuit board with a cut-out shape, and the minimum spatial distance between the conductive lines on the signal processing circuit board and the inner wall of the housing is greater than 2 mm.

[0009] In one possible implementation, the insulating pad is fitted onto the pin of the pressure sensor, and the signal processing circuit board is supported and fixed to the pin end by the insulating pad.

[0010] In one possible implementation, a pressure interface and an electrical interface are also included, the pressure interface being welded to one end of the housing, and the electrical interface including a pack plug and disposed at the other end of the housing.

[0011] In one possible implementation, O-rings are provided at the connection between the pressure port and the housing, as well as at the mounting location of the Pack plug.

[0012] In one possible implementation, the signal processing circuit board is electrically connected to the Pack plug-in via flexible wires, which are covered by epoxy resin.

[0013] In one possible implementation, the epoxy resin adhesive is a dense solid insulating layer that fills all voids within the housing.

[0014] In one possible implementation, the housing is further provided with damping pads for support and cushioning.

[0015] In one possible implementation, the pressure sensor's Kovar pins pass through the glass insulator and are connected to the outside.

[0016] Compared with the prior art, this application has the following beneficial effects: This application provides a high-insulation-strength pressure transmitter that, through a triple-synergistic design of sensor encapsulation insulation, circuit board mounting insulation, and overall potting insulation, eliminates the insulation weakness of the sensor body from the source, eliminates the creepage risk caused by air gaps, significantly improves the overall insulation strength and structural stability of the transmitter, ensures no insulation failure risk in high-pressure and high-humidity environments, and enhances the equipment's vibration and shock resistance, laying a structural foundation for subsequent improvements in electromagnetic compatibility.

[0017] In one possible implementation, a triple-coordinated design of sensor encapsulation insulation, circuit board mounting insulation, and overall potting insulation eliminates the source of sensor body insulation weaknesses, removes the risk of creepage caused by air gaps, significantly improves the overall insulation strength and structural stability of the transmitter, ensures no insulation failure risks in high-voltage and high-humidity environments, and enhances the equipment's vibration and shock resistance, laying a structural foundation for subsequent improvements in electromagnetic compatibility.

[0018] In one possible implementation, the welded connection between the pressure interface and the housing ensures structural sealing and mechanical strength, adapting to the pressure transmission requirements of high-pressure media; the electrical interface composed of the Pack plug-in enables reliable connection between the external circuit and the internal circuit board, and the overall structural design takes into account both the sealing of pressure measurement and the stability of signal transmission, providing convenience for the installation and integration of the equipment in the industrial field.

[0019] In one possible implementation, the welded connection between the pressure interface and the housing ensures structural sealing and mechanical strength, adapting to the pressure transmission requirements of high-pressure media; the electrical interface composed of the Pack plug-in enables reliable connection between the external circuit and the internal circuit board, and the overall structural design takes into account both the sealing of pressure measurement and the stability of signal transmission, providing convenience for the installation and integration of the equipment in the industrial field. Attached Figure Description

[0020] Figure 1 A partial cross-sectional view of a pressure transmitter with high insulation strength provided in this application; Figure 2 An exploded view of a pressure transmitter with high insulation strength provided in this application.

[0021] The following are the reference numerals in the diagram: 1. Pressure sensor; 2. Signal processing circuit board; 3. Pressure interface; 4. Housing; 5. Damping gasket; 6. Pack plug; 7. Insulating gasket; 8. O-ring; 9. Epoxy resin. Detailed Implementation

[0022] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.

[0023] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0024] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly defined. The specific embodiments of this application will be further described in detail below with reference to the accompanying drawings.

[0025] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0026] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0027] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0028] like Figure 1 and Figure 2 As shown, this application discloses a high-insulation-strength pressure transmitter, which may include a housing 4, a pressure sensor 1 disposed inside the housing 4, and a signal processing circuit board 2. The pressure sensor 1 has an encapsulation structure formed by a metal sintered component and a glass insulator. The signal processing circuit board 2 is mounted and fixed by an insulating gasket 7. The internal cavity of the housing 4 is entirely encapsulated by epoxy resin 9, which covers the pressure sensor 1, the signal processing circuit board 2, and their connecting wires.

[0029] Specifically, the housing 4 is made of 304 stainless steel and houses an MPM285 pressure sensor 1, which is formed by sintering a custom-made metal sintered part with a 3mm thick glass insulator.

[0030] The signal processing circuit board 2 is fixed to the end of the sensor pin by an insulating pad 7 made of FR-4 material.

[0031] The cavity inside the housing 4 is filled with high-temperature resistant epoxy resin 9. The resin fills all the gaps inside the housing 4, completely covering the pressure sensor 1, the signal processing circuit board 2 and the connecting wires, forming a dense solid insulating protective layer.

[0032] In this embodiment, the triple collaborative design of sensor encapsulation insulation, circuit board mounting insulation, and overall potting insulation eliminates the insulation weakness of the sensor body from the source, eliminates the creepage risk caused by air gaps, significantly improves the overall insulation strength and structural stability of the transmitter, ensures no insulation failure risk in high-voltage and high-humidity environments, and enhances the equipment's vibration and shock resistance, laying a structural foundation for subsequent improvements in electromagnetic compatibility.

[0033] In one possible embodiment, the glass insulator is welded and encapsulated within the sintered metal component, and the metal body of the pressure sensor 1 is electrically isolated from the outside through the glass insulator.

[0034] Optionally, the glass insulator is a thickened glass insulator, which can be made of high borosilicate glass and welded and fixed in the mounting hole of the metal sintered part through a high-temperature sintering process. The metal body of the pressure sensor 1 is tightly attached to the metal sintered part, and the Kova pin of the sensor extends to the outside through the central through hole of the glass insulator to achieve electrical isolation between the metal body and the external circuit. The sensor packaging structure has been tested and can withstand high voltage impacts of AC2200V and above.

[0035] In this embodiment, reliable electrical isolation between the sensor body and the outside is achieved by welding and encapsulating the glass insulator and the metal sintered part. The thickened high borosilicate glass insulator has both excellent bulk insulation strength and surface creepage distance, breaking through the insulation limit of conventional sensors at the core component level. This avoids the degradation of the overall performance caused by the insulation failure of the sensor body, and provides core protection for the transmitter to achieve an insulation strength of 1800VAC.

[0036] In one possible embodiment, the signal processing circuit board 2 is a double-layer circuit board with a cut-out shape, and the minimum spatial distance between the conductive lines on the signal processing circuit board 2 and the inner wall of the housing 4 is greater than 2mm.

[0037] Specifically, the signal processing circuit board 2 is a double-layer circuit board made of FR-4 material. The shape is precisely cut according to the internal space dimensions of the housing 4. The minimum space distance between the power lines, signal lines and other conductive lines on the circuit board and the inner wall of the housing 4 is controlled to be greater than 2mm. The edges of the circuit board are rounded to avoid the phenomenon of tip discharge.

[0038] In this embodiment, by customizing the shape of the circuit board and optimizing the spatial distance, the electrical clearance and creepage distance requirements for high insulation level between the conductive lines and the housing 4 are ensured, effectively reducing the risk of discharge under high voltage. At the same time, the internal space of the housing 4 is rationally utilized to achieve miniaturization of the equipment while ensuring insulation performance and improving installation adaptability.

[0039] In one possible embodiment, the insulating pad 7 is fitted onto the pin of the pressure sensor 1, and the signal processing circuit board 2 is supported and fixed to the end of the pin by the insulating pad 7.

[0040] Optionally, the insulating pad 7 is a ring structure made of FR-4 material. Its inner diameter is adapted to the diameter of the Kova pin of the pressure sensor 1, and its outer diameter is larger than the diameter of the mounting hole of the signal processing circuit board 2. The insulating pad 7 is fitted in the middle of the pin, and the signal processing circuit board 2 is fixed to the end of the pin by welding. The insulating pad 7 forms an insulating support gap between the circuit board and the sensor body.

[0041] In this embodiment, the electrical isolation between the signal processing circuit board 2 and the sensor body is achieved by supporting and fixing the insulating pad 7, avoiding the risk of short circuit caused by direct contact between the two. At the same time, the elasticity of the pad can buffer the impact of vibration on the circuit board, and the ring structure design ensures installation stability. Combined with the optimized spatial layout of the circuit board, the reliability of the overall insulation system is further enhanced.

[0042] In one possible embodiment, a pressure interface 3 and an electrical interface are also included. The pressure interface 3 is welded to one end of the housing 4, and the electrical interface includes a Pack plug 6 and is disposed at the other end of the housing 4.

[0043] Optionally, the pressure port 3 is made of stainless steel and is sealed to one end of the housing 4 by argon arc welding. The pressure port 3 has a pressure transmission channel inside that contacts the measured medium.

[0044] The electrical interface includes a Pack Plug 6, which is fixed to the other end of the housing 4 by a threaded connection. The pins of the Pack Plug 6 extend into the interior of the housing 4 for electrical connection with the signal processing circuit board 2.

[0045] In this embodiment, the welded connection between the pressure interface 3 and the housing 4 ensures structural sealing and mechanical strength, and can adapt to the pressure transmission requirements of high-pressure media; the electrical interface formed by the Pack plug-in 6 realizes reliable docking between the external circuit and the internal circuit board. The overall structural design takes into account both the sealing of pressure measurement and the stability of signal transmission, providing convenience for the installation and integration of the equipment in the industrial field.

[0046] In one possible embodiment, an O-ring 8 is provided at the mounting points of the housing 4 and the Pack plug 6.

[0047] Optionally, nitrile rubber O-rings 8 are embedded on the outside of the welding part between the pressure port 3 and the housing 4, and at the connection part between the Pack plug 6 and the housing 4. During installation, pre-compression is used to achieve a sealed fit, preventing external moisture and dust from entering the interior of the housing 4.

[0048] In this embodiment, the O-ring 8 further enhances the sealing performance of the equipment, effectively preventing external humidity, dust and other harsh environmental factors from entering the housing 4, avoiding problems such as moisture absorption of insulation materials and short circuits, extending the service life of the insulation system, ensuring long-term stable operation of the transmitter in high humidity and dusty industrial conditions, and improving the environmental adaptability of the equipment.

[0049] In one possible embodiment, the signal processing circuit board 2 is electrically connected to the Pack plug-in 6 via a flexible wire, which is covered by the epoxy resin adhesive 9.

[0050] Optionally, the output end of the signal processing circuit board 2 is soldered with a heat-resistant flexible wire. The flexible wire is wrapped with an insulating sheath. The other end of the wire is fixedly connected to the pin of the Pack plug-in 6 by crimping, ensuring the connection redundancy between the circuit board and the Pack plug-in 6. The entire flexible wire and connection part are completely covered by epoxy resin 9.

[0051] In this embodiment, the connection method of the flexible wire adapts to the spatial layout inside the housing 4, avoiding the risk of breakage of the rigid connection under vibration. The double coating of the insulating sheath and epoxy resin 9 ensures the insulation performance of the wire, prevents short circuits or insulation failure caused by wire damage, ensures the stability and reliability of signal transmission, and enables the device to pass strict electromagnetic compatibility certification.

[0052] In one possible embodiment, the epoxy resin adhesive 9 is a dense solid insulating layer that fills all the voids within the housing 4.

[0053] Specifically, a low-viscosity, high-filling-rate epoxy resin adhesive 9 can be selected and injected into the housing 4 through a vacuum potting process. During the potting process, the flow rate of the adhesive and the exhaust pressure are controlled to ensure that the adhesive completely fills the tiny gaps inside the housing 4. After curing, a dense solid insulating layer without bubbles or cracks is formed, and the thickness of the insulating layer uniformly covers the surface of all internal components.

[0054] In this embodiment, the dense epoxy resin adhesive 9 solid insulation layer completely eliminates the air gap inside the housing 4, transforming air insulation into more stable solid insulation, effectively preventing creepage or breakdown between conductors at different potentials caused by moisture and dust, while also fixing, buffering and protecting the internal components, significantly improving the equipment's anti-interference ability, mechanical strength and environmental tolerance.

[0055] Optionally, the damping pad 5 is made of 304 stainless steel, and its shape is customized according to the internal structure of the pressure interface 3. It is placed between the pressure sensor 1 and the pressure interface 3 and has good elasticity and buffering performance.

[0056] In this embodiment, the damping pad 5 provides reliable support and buffer for the pressure sensor 1 and the signal processing circuit board 2, effectively absorbing the vibration and shock generated during transportation, installation and operation of the equipment, preventing internal components from becoming loose, damaged or broken due to vibration, extending the mean time between failures of the equipment, reducing maintenance costs and improving the operational stability of the equipment under harsh working conditions.

[0057] In one possible embodiment, the Kova pin of the pressure sensor 1 is connected to the outside through the glass insulator.

[0058] Specifically, the pressure sensor 1 has a Kova pin made of a corrosion-resistant alloy with a diameter of 0.5mm. The pin passes through the central through hole of the glass insulator, and the contact area between the pin and the glass insulator is sealed at high temperature to ensure that there is no gap between them.

[0059] In this embodiment, the sealed fit between the Kova pins and the glass insulator ensures the airtightness and insulation of the sensor package, preventing moisture from entering the sensor and affecting measurement accuracy. At the same time, the corrosion-resistant alloy material improves the service life of the pins, ensuring the connection stability and electrical conductivity between the sensor and the circuit board, and providing a guarantee for the long-term reliable operation of the equipment.

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them; although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications to the technical solutions described in the foregoing embodiments, or equivalent substitutions for some or all of the technical features, do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A pressure transmitter with high insulation strength, comprising a housing (4), a pressure sensor (1) disposed inside the housing (4), and a signal processing circuit board (2), characterized in that: The pressure sensor (1) has an encapsulation structure consisting of a metal sintered component and a glass insulator; The signal processing circuit board (2) is mounted and fixed by an insulating pad (7); The internal cavity of the housing (4) is completely encapsulated with epoxy resin (9), which covers the pressure sensor (1), the signal processing circuit board (2) and its connecting wires.

2. The high insulation strength pressure transmitter according to claim 1, characterized in that, The glass insulator is welded and encapsulated in the metal sintered part, and the metal body of the pressure sensor (1) is electrically isolated from the outside through the glass insulator.

3. The high insulation strength pressure transmitter according to claim 1, characterized in that, The signal processing circuit board (2) is a double-layer circuit board with a cut-out shape. The minimum spatial distance between the conductive lines on the signal processing circuit board (2) and the inner wall of the housing (4) is greater than 2mm.

4. The high insulation strength pressure transmitter according to claim 1 or 3, characterized in that, The insulating pad (7) is sleeved on the pin of the pressure sensor (1), and the signal processing circuit board (2) is supported and fixed to the end of the pin by the insulating pad (7).

5. The high insulation strength pressure transmitter according to claim 1, characterized in that, It also includes a pressure port (3) and an electrical interface, the pressure port (3) being welded to one end of the housing (4), and the electrical interface including a pack plug (6) and disposed at the other end of the housing (4).

6. The high insulation strength pressure transmitter according to claim 5, characterized in that, An O-ring (8) is provided at the mounting location of the Pack plug (6).

7. The high insulation strength pressure transmitter according to claim 5, characterized in that, The signal processing circuit board (2) is electrically connected to the Pack plug-in (6) via a flexible wire, which is covered by the epoxy resin adhesive (9).

8. The high insulation strength pressure transmitter according to claim 1, characterized in that, The epoxy resin adhesive (9) is a dense solid insulating layer that fills all the voids in the housing (4).

9. The high insulation strength pressure transmitter according to claim 1, characterized in that, An insulating pad (7) for support is also provided inside the housing (4).

10. The high insulation strength pressure transmitter according to claim 1, characterized in that, The pressure sensor (1) has its Kova pins passing through the glass insulator and connected to the outside.

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