High-stability vehicle high-pressure sensor packaging structure and packaging method

Abstract

The invention discloses a high-stability vehicle high-pressure sensor packaging structure and packaging method, and relates to the technical field of pressure sensors, the high-stability vehicle high-pressure sensor packaging structure comprises a plastic connector, a PIN, a metal hexagonal shell, a circuit board, an elastic sheet, a metal gasket, a sealing ring and a pressure sensing element; the metal hexagonal shell, the sealing ring and the pressure sensing element are fixedly connected to form a pressure-bearing and sealed main body structure, the circuit board is arranged in the metal hexagonal shell and is electrically connected with the pressure sensing element, and the elastic sheet forms an elastic electric connection path between the circuit board and the PIN; the metal gasket is fixed below the circuit board and is in welded connection with the metal hexagonal shell; the metal hexagonal shell is connected with the plastic connector in a riveting manner, so that the PINs are led out from the plastic connector; according to the high-pressure sensor packaging structure, pressure-bearing sealing and electric connection are effectively separated through cooperation of multiple connection modes, the connection stability under high pressure and complex working conditions is improved, meanwhile, the integration degree and appearance adaptability of the packaging structure are improved, and the high-pressure sensor packaging structure is suitable for miniaturization and high-reliability application of a vehicle high-pressure sensor.

Description

Technical Field

[0001] This invention relates to the field of pressure sensor technology, and in particular to a high-stability automotive high-pressure sensor packaging structure and packaging method. Background Technology

[0002] Pressure sensors, as key components in automotive electronic systems, are widely used in fuel supply systems, engine control systems, transmission control systems, and braking and safety systems to achieve real-time detection of fuel pressure, hydraulic pressure, or gas pressure. As the automotive industry develops towards higher reliability, higher integration, and greater intelligence, higher requirements are being placed on automotive pressure sensors in terms of operational stability, structural compactness, and installation adaptability.

[0003] Existing automotive high-pressure sensors typically employ a packaged structure combining a metal housing and an internal pressure-sensitive core, with electrical connections mostly using PIN pin leads. This type of structure satisfies basic measurement functions while also providing a certain degree of sealing and mechanical strength, thus finding widespread application in areas such as fuel systems. However, current pressure sensors often use fixed welding, adhesive bonding, or rigid support methods to assemble the core, circuit board, and lead assembly, resulting in relatively simple connection methods between internal components.

[0004] In practical applications, the dimensions and installation methods of the internal fixed structure are limited during the design phase, resulting in limited room for adjustment in the overall package size, proportions, and interface layout of the pressure sensor. When applications raise different requirements regarding sensor installation space, boundary dimensions, or structural form, existing structures are often difficult to adapt flexibly, necessitating overall structural reconstruction or the development of new molds. This leads to long development cycles, high costs, and hinders product serialization and platform design.

[0005] Furthermore, in existing packaging structures, the stability of connections between internal components still has room for improvement under complex automotive conditions such as high temperature, high pressure, and vibration. Some structures are susceptible to thermal stress, mechanical stress, or the accumulation of assembly tolerances during long-term use, which can adversely affect the measurement stability and reliability of the sensors. At the same time, some existing structures rely heavily on manual operation during assembly, with limited automation, which also restricts production efficiency and consistency to some extent.

[0006] In summary, the existing technology has at least the following technical problems: Existing pressure sensors suffer from technical problems such as limited overall boundary dimensions and shape options due to their internal structure, need for improved connection stability under high pressure and complex operating conditions, and insufficient integration of the packaging structure. Summary of the Invention

[0007] The purpose of this invention is to provide a high-stability automotive high-pressure sensor packaging structure and packaging method to solve the technical problems of existing pressure sensors, such as limited overall boundary size and shape selection due to internal structure limitations, insufficient connection stability under high pressure and complex working conditions, and inadequate integration of packaging structure.

[0008] The preferred technical solutions among the many technical solutions provided by this invention can produce a variety of technical effects, which are described in detail below.

[0009] To address the aforementioned technical problems, the present invention provides the following technical solution: This invention provides a high-stability automotive high-pressure sensor packaging structure, including a plastic connector, a PIN pin, a hexagonal metal shell, a circuit board, a spring, a metal washer, a sealing ring, and a pressure-sensing element. The hexagonal metal shell is fixedly connected to the pressure-sensing element to form a pressure-bearing and sealing main structure. The circuit board is disposed inside the hexagonal metal shell and electrically connected to the pressure-sensing element. The spring forms an elastic electrical connection path between the circuit board and the PIN pin. The metal washer is fixed below the circuit board, and the spring is fixed above the circuit board. The metal washer is fixedly connected to the inner stepped surface of the hexagonal metal shell by welding. The sealing ring is disposed in the sealing gap between the metal washer and the hexagonal metal shell. The hexagonal metal shell and the plastic connector are fixedly connected by riveting, allowing the PIN pin to extend from the plastic connector.

[0010] In one embodiment, the hexagonal metal shell is fixedly connected to the pressure-sensing element by laser welding.

[0011] In one embodiment, the metal washer is fixed to the circuit board by reflow soldering SMT; the circuit board is fixed to the spring contact by reflow soldering SMT.

[0012] In one embodiment, the metal washer is fixedly connected to the inner stepped surface of the metal hexagonal shell by three-point electric welding.

[0013] In one embodiment, the spring is a mountable elastic conductive component, and the free end of the spring contacts the conductive area within the PIN pin and / or the plastic connector to form an elastic crimp connection.

[0014] In one embodiment, the spring and the PIN are pre-welded and fixed, and during assembly, the free end of the spring is elastically pressed against the pad area of ​​the circuit board to achieve electrical connection.

[0015] In one embodiment, the circuit board is provided with a floating limiting vibration isolation structure in the circumferential direction. The floating limiting vibration isolation structure is used to provide axial limiting and pre-tightening for the circuit board, while causing the circuit board to generate a radial micro-displacement within a preset range relative to the metal hexagonal shell, so as to release assembly stress and / or thermal stress and reduce vibration transmission, thereby improving the connection stability under high pressure and complex working conditions, and reducing the impact of stress concentration in the metal hexagonal shell on the reliability of the circuit board and its solder joints.

[0016] In one embodiment, the floating limiting vibration isolation structure includes at least three elastic limiting members arranged circumferentially at intervals. The elastic limiting members are disposed at the outer peripheral edge of the circuit board and elastically abut against the inner wall of the metal hexagonal shell. Each elastic limiting member has a contact portion facing the inner wall of the metal hexagonal shell. The contact portion is an arc surface and / or a chamfered surface, so as to provide axial limiting and pre-tightening for the circuit board while causing the circuit board to generate radial micro-displacement relative to the metal hexagonal shell, thereby achieving vibration isolation and stress release and improving connection stability.

[0017] In one embodiment, the pressure-sensing element includes a stainless steel housing, a strain gauge, and a glass adhesive layer for bonding the strain gauge; the stainless steel housing has a connecting end and a sensing end; the strain gauge is bonded to the sensing end of the stainless steel housing through the glass adhesive layer and sintered for fixation; the connecting end has a connecting thread for connecting to the position to be measured; the connecting end has a drainage cavity for introducing the fluid to be measured into the vicinity of the sensing end, so that the pressure of the fluid to be measured is transmitted to the strain gauge; the sensing end extends into the hexagonal metal housing and faces the circuit board, and the electrical signal of the strain gauge is led out to the circuit board through the metal washer inside the hexagonal metal housing by a binding wire.

[0018] A packaging method for a high-pressure sensor for automobiles is also provided to achieve a high-stability packaging structure for a high-pressure sensor for automobiles, including the following steps: S1, Assembling the main structure: fitting the pressure-sensing element into a metal hexagonal shell and installing a sealing ring; S2. Sub-component assembly: Fix the spring and metal washer to the circuit board by reflow soldering. S3. Assembly: The pads of the strain gauge of the pressure sensing element are soldered to the pads of the circuit board through the binding wire. Then, the metal washer is soldered to the inner stepped surface of the metal hexagonal shell. Finally, the pressure sensing element is soldered to the metal hexagonal shell for fixation. S4. Install the plastic connector: Assemble the plastic connector and make the pin and the spring form an elastic electrical connection path; S5. Packaging: The metal hexagonal shell and the plastic connector are riveted together to complete the packaging.

[0019] The beneficial effects of this invention are as follows: (1) Effectively improve the adaptability of the packaging structure to the overall boundary size and shape structure. By forming a modular encapsulation structure centered on a circuit board, metal gaskets, and springs within a hexagonal metal shell, the internal functional units no longer rely on bulky, rigid, integrated fasteners for positioning. Instead, reliable support is achieved through welding the metal gaskets to the stepped inner surface of the hexagonal metal shell. This structure decouples the pressure-bearing and sealing functions from the electrical connection functions, allowing for flexible design of the sensor's overall height, internal hierarchy, and interface layout without altering the core pressure measurement and sealing performance. This addresses the issue of existing pressure sensors having significant limitations on the selectivity of their internal structure in terms of dimensions and boundary morphology.

[0020] (2) Significantly improves connection stability and reliability under high pressure and complex working conditions. The pressure-sensing element is fixedly connected to the metal hexagonal shell to form a stable pressure-bearing and sealing body, avoiding structural deformation and stress concentration caused by the transmission of pressure load through multiple structures. At the same time, the circuit board and the external pins are connected by springs to form an elastic electrical connection path. Compared with rigid welding or direct plugging, it can buffer assembly tolerances, thermal expansion and contraction and mechanical vibration under complex automotive conditions such as high temperature, vibration and pressure fluctuation, thereby reducing the risk of solder joint fatigue and contact failure and improving the long-term stability of the overall electrical connection.

[0021] (3) Improve the integration of the packaging structure and reduce manufacturing complexity and cost. By integrating the pressure-bearing housing, sealing structure, electrical connection structure, and circuit board support structure within a single packaging structure, and employing mature assembly processes such as welding, reflow soldering, and riveting, reliance on additional fasteners, complex brackets, or multi-stage assembly processes is reduced, facilitating automated assembly and mass production. This not only improves product consistency and production efficiency but also effectively reduces manufacturing costs and maintenance complexity.

[0022] (4) Enhance the versatility and scalability of the packaging structure in automotive applications. Because the packaging structure of this technical solution has a high degree of independence and modularity in terms of internal connection methods and functional partitions, it can be adapted to different pressure levels, interface specifications, or installation space requirements by adjusting the size of the metal hexagonal shell, the shape of the circuit board, or the structure of the plastic connector, without having to fundamentally modify the overall packaging principle. This further enhances the versatility and expanded application value of this packaging structure in the field of automotive high-pressure sensors.

[0023] In summary, this technical solution, through structural hierarchical reconstruction and collaborative design of multiple connection methods, achieves miniaturization, high stability, and high integration of the packaging structure while ensuring high-pressure sealing and measurement reliability. It effectively solves the technical problems in existing technologies, such as internal structure limiting application selectivity, insufficient connection stability under complex working conditions, and low packaging integration. Attached Figure Description

[0024] To more clearly illustrate the technical solution of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is an isometric structural diagram of the high-stability automotive high-pressure sensor packaging structure of the present invention; Figure 2 This is a cross-sectional schematic diagram of the high-stability automotive high-pressure sensor packaging structure of the present invention; Figure 3 This is a partial structural schematic diagram of the high-stability automotive high-pressure sensor packaging structure according to the second embodiment of the present invention; Figure 4 This is a partial structural schematic diagram of the high-stability automotive high-pressure sensor packaging structure according to the third embodiment of the present invention; Figure 5 This is a top view schematic diagram of the high-stability automotive high-pressure sensor packaging structure according to the fourth embodiment of the present invention; Figure 6 This is a schematic diagram of the process steps for packaging the high-pressure sensor for vehicles according to the present invention.

[0026] The reference numerals in the attached figures are as follows: 1. Plastic connector; 2. Pins; 3. Metal hexagonal shell; 31. Sealing gap; 32. Inner stepped surface; 4. Circuit board; 41. Solder pad area; 5. Shrapnel; 6. Metal washers; 7. Sealing ring; 8. Pressure sensing element; 81. Stainless steel housing; 82. Connection end; 821. Connection thread; 822. Drainage cavity; 83. Sensing end; 84. Strain gauge; 85. Glass adhesive layer; 86. Binding wire; 9. Floating limiting vibration isolation structure; 91. Elastic limiting component; 911. Contact part. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0028] The specific implementation provides a high-stability automotive high-pressure sensor packaging structure and packaging method. The packaging structure includes a plastic connector, a PIN pin, a hexagonal metal shell, a circuit board, a spring, a metal washer, a sealing ring, and a pressure-sensing element. The hexagonal metal shell is fixedly connected to the pressure-sensing element to form a pressure-bearing and sealing main structure. The circuit board is disposed inside the hexagonal metal shell and electrically connected to the pressure-sensing element. The spring is used to form an elastic electrical connection path between the circuit board and the PIN pin. The metal washer is fixed under the circuit board and welded to the inner stepped surface of the hexagonal metal shell. The sealing ring is disposed between the metal washer and the hexagonal metal shell. The hexagonal metal shell and the plastic connector are fixedly connected by riveting, so that the PIN pin is led out from the plastic connector. By coordinating multiple connection methods, the pressure-bearing sealing structure and electrical connection structure are effectively separated. This improves connection stability under high pressure and complex operating conditions while enhancing the integration and shape adaptability of the packaging structure. It is suitable for miniaturization and high reliability applications of automotive high-pressure sensors. It effectively solves the technical problems of existing pressure sensors, such as the limitation of overall boundary size and shape selectivity due to internal structure, the need to improve connection stability under high pressure and complex operating conditions, and insufficient integration of packaging structure.

[0029] The first implementation of a high-stability automotive high-pressure sensor packaging structure, for example Figures 1 to 3 As shown, the device includes a plastic connector 1, a pin 2, a hexagonal metal shell 3, a circuit board 4, a spring 5, a metal washer 6, a sealing ring 7, and a pressure-sensing element 8. The hexagonal metal shell 3 and the pressure-sensing element 8 are fixedly connected to form a main structure for bearing pressure and sealing. The circuit board 4 is disposed inside the hexagonal metal shell 3 and is electrically connected to the pressure-sensing element 8. The spring 5 is used to form an elastic electrical connection path between the circuit board 4 and the pin 2. The metal washer 6 is fixed below the circuit board 4, the spring 5 is fixed above the circuit board 4, and the metal washer 6 is fixedly connected to the inner stepped surface 32 of the hexagonal metal shell 3 by welding. The sealing ring 7 is set in the sealing gap 31 between the metal gasket 6 and the metal hexagonal shell 3; the metal hexagonal shell 3 and the plastic connector 1 are fixedly connected by riveting, so that the PIN pin 2 is led out from the plastic connector 1.

[0030] Specifically, compared with existing technologies, the high-stability automotive high-pressure sensor packaging structure provided by this technical solution has at least the following technical effects: effectively improving the adaptability of the packaging structure to the overall boundary dimensions and shape; by forming a modular packaging structure with a circuit board 4, metal gasket 6, and spring 5 as the core inside the metal hexagonal shell 3, the internal functional units no longer rely on large-volume, rigid integrated fasteners for positioning, but instead achieve reliable support through the welding of the metal gasket 6 to the inner stepped surface 32 of the metal hexagonal shell 3. This structure decouples the pressure-bearing sealing function from the electrical connection function, which is beneficial for flexible design of the overall height of the sensor, internal hierarchical relationships, and interface layout without changing the core pressure measurement and sealing performance, thereby solving the problem that the internal structure of existing pressure sensors has large limitations on the selectivity of external dimensions and boundary shapes.

[0031] Significantly improves connection stability and reliability under high pressure and complex operating conditions; the pressure-sensing element 8 and the metal hexagonal shell 3 are fixedly connected to form a stable pressure-bearing and sealing body, avoiding structural deformation and stress concentration caused by pressure load transmission through multiple structures; at the same time, the circuit board 4 and the external PIN pin 2 are connected by a spring sheet 5 to form an elastic electrical connection path. Compared with rigid welding or direct plugging, it can buffer assembly tolerances, thermal expansion and contraction and mechanical vibration under complex automotive operating conditions such as high temperature, vibration and pressure fluctuation, thereby reducing the risk of solder joint fatigue and contact failure and improving the long-term stability of the overall electrical connection.

[0032] Improving the integration of the packaging structure reduces manufacturing complexity and cost. By integrating the pressure-bearing housing, sealing structure, electrical connection structure, and circuit board support structure within the same packaging structure, and employing mature processes such as welding, reflow soldering, and riveting for assembly, reliance on additional fasteners, complex brackets, or multi-level assembly processes is reduced, facilitating automated assembly and mass production. This not only improves product consistency and production efficiency but also effectively reduces manufacturing costs and maintenance difficulty.

[0033] Enhance the versatility and scalability of the packaging structure in automotive applications; due to the high degree of independence and modularity of the packaging structure in terms of internal connection methods and functional partitions, it can be adapted to different pressure levels, interface specifications, or installation space requirements by adjusting the size of the metal hexagonal shell 3, the shape of the circuit board 4, or the structure of the plastic connector 1, without fundamentally modifying the overall packaging principle. This further enhances the versatility and expanded application value of the packaging structure in the field of automotive high-pressure sensors.

[0034] In summary, this technical solution, through structural hierarchical reconstruction and collaborative design of multiple connection methods, achieves miniaturization, high stability, and high integration of the packaging structure while ensuring high-pressure sealing and measurement reliability. It effectively solves the technical problems in existing technologies, such as internal structure limiting application selectivity, insufficient connection stability under complex working conditions, and low packaging integration.

[0035] As one alternative implementation method: Regarding the specific structure of the aforementioned pressure-sensing element 8, this embodiment is, for example... Figures 1 to 3 As shown, the pressure-sensing element 8 includes a stainless steel housing 81, a strain gauge 84, and a glass adhesive layer 85 for bonding the strain gauge 84. The stainless steel housing 81 is provided with a connecting end 82 and a sensing end 83. The strain gauge 84 is bonded to the sensing end 83 of the stainless steel housing 81 through the glass adhesive layer 85 and sintered for fixation. The connecting end 82 is provided with a connecting thread 821 for connecting to the position to be measured. The connecting end 82 is provided with a drainage cavity 822 for introducing the fluid to be measured and placing it near the sensing end 83, so that the pressure of the fluid to be measured is transmitted to the strain gauge 84. The sensing end 83 extends into the metal hexagonal shell 3 and faces the circuit board 4. The electrical signal of the strain gauge 84 is led out to the circuit board 4 through the metal washer 6 inside the metal hexagonal shell 3 via the binding wire 86.

[0036] In application, the strain gauge 84 is bonded and sintered to the sensing end 83 of the stainless steel housing 81 via a glass adhesive layer 85, forming a stable mechanical and thermal coupling relationship between the strain gauge 84 and the stainless steel housing 81. This allows for accurate transmission of pressure changes generated by the fluid to be measured within the drainage cavity 822 to the strain gauge 84, achieving high-sensitivity and high-repeatability pressure sensing. Simultaneously, the sensing end 83 extends into the interior of the hexagonal metal housing 3 and faces the circuit board 4, shortening the signal output path of the strain gauge 84. The signal is then directly led to the circuit board 4 via a binding wire 86, effectively reducing intermediate transition structures and solder joints, thereby lowering interference and failure risks during signal transmission. The structure of the pressure-sensing element 8, in conjunction with the pressure-bearing sealed body formed by the hexagonal metal housing 3, ensures a clear pressure loading path and a well-defined stress transmission direction, facilitating measurement stability under high-pressure conditions and addressing the problems of complex structure, lengthy signal paths, and insufficient reliability of existing pressure-sensing elements 8.

[0037] The stainless steel housing 81 can be made of stainless steel materials of different strength grades or corrosion resistance grades; the cross-sectional shape and length of the drainage cavity 822 need to be adjusted according to different pressure levels or fluid characteristics; the glass adhesive layer 85 also needs to be selected with different formulas or thicknesses according to the requirements of temperature resistance and fatigue resistance to adapt to different automotive working conditions.

[0038] Regarding the specific connection method between the aforementioned hexagonal metal shell 3 and the pressure-sensing element 8, this embodiment is as follows: Figures 1 to 3As shown, the metal hexagonal shell 3 and the pressure-sensing element 8 are fixedly connected by laser welding.

[0039] In application, the pressure-sensing element 8 is fixedly connected to the metal hexagonal shell 3 by laser welding, forming a metallurgical bond structure with high strength and low heat-affected zone in the welding area. This creates a stable pressure-bearing and sealing path between the pressure-sensing element 8 and the metal hexagonal shell 3. The laser welding connection works synergistically with the internal sealing structure formed by the subsequent metal gasket 6 and sealing ring 7, ensuring that the pressure load is mainly borne and directly transmitted by the metal shell. This avoids local stress concentration or sealing failure caused by force transmission through multiple structures, thus significantly improving the reliability and consistency of the packaging structure under high pressure, frequent pressure fluctuations, and temperature changes. This solves the problems of insufficient weld strength or poor sealing stability in traditional welding methods.

[0040] Laser welding can be performed in the form of circumferential welding, spot welding, or continuous welding. Welding parameters such as power, welding speed, and focal length need to be adjusted according to the thickness of the metal material and the pressure level. In some embodiments, the welding area can be pretreated before welding or a sealing test can be performed after welding to further improve the welding quality.

[0041] Regarding the specific connection process between the aforementioned circuit board 4, the metal hexagonal shell 3, and the spring contact 5, this embodiment is as follows: Figures 1 to 3 As shown, the metal washer 6 is fixed to the circuit board 4 by reflow soldering SMT; the circuit board 4 is fixed to the spring contact 5 by reflow soldering SMT.

[0042] In application, by fixing the metal washer 6 to the circuit board 4 and the spring contact 5 to the circuit board 4 using reflow soldering SMT, a highly consistent and controllable assembly relationship is formed between the electrical connection structure and the circuit board 4, which is conducive to automated placement and mass production. Specifically, the metal washer 6 forms a stable support below the circuit board 4 and serves as a structural load-bearing and positioning component, while the spring contact 5 forms an elastic electrical connection path above the circuit board 4. The two are spatially layered and work together through the circuit board 4, resulting in a clear structural stress path and reliable electrical connections. The reflow soldering SMT process, combined with subsequent riveting and elastic crimping, effectively reduces manual assembly errors and solder joint fatigue risks, solving the problems of poor internal electrical connection consistency and insufficient automation in existing technologies.

[0043] In other embodiments, the reflow soldering process may use lead-free solder or other environmentally friendly solder; the mounting positions, pad sizes and solder paste types of the metal gaskets 6 and springs 5 ​​may be optimized according to different current or vibration requirements.

[0044] In some implementations, the circuit board 4 after soldering can also be subjected to online inspection or reliability testing.

[0045] Regarding the specific connection method between the aforementioned hexagonal metal shell 3 and the metal washer 6, this embodiment is as follows: Figures 1 to 3 As shown, the metal washer 6 and the inner stepped surface 32 of the metal hexagonal shell 3 are fixedly connected by three-point electric welding.

[0046] In application, a three-point electric welding connection is used between the metal washer 6 and the inner stepped surface 32 of the metal hexagonal shell 3 to ensure reliable positioning and support of the metal washer 6 in the axial direction, while maintaining a certain degree of structural flexibility in the circumferential direction. This facilitates the release of thermal and assembly stresses during assembly and operation. This three-point fixing method works in synergy with the circuit board 4, spring 5, and sealing ring 7, ensuring overall stability of the internal structure while avoiding excessive rigidity. This reduces the impact of stress concentration on the reliability of the circuit board 4 and solder joints, solving the problem of internal stress accumulation caused by full-circumferential rigid welding in the prior art.

[0047] The three-point welding points can be evenly or non-uniformly distributed along the circumference; the number of welding points can be adjusted to more than three points according to the structural strength requirements.

[0048] In some implementations, a combination of spot welding and local continuous welding may be used to achieve a balance between strength and stress relief.

[0049] A second embodiment of the high-stability automotive high-pressure sensor packaging structure, for example Figures 1 to 3 As shown, the difference between this embodiment and the first embodiment is that the spring 5 is a mountable elastic conductive component, and the free end of the spring 5 contacts the conductive area in the PIN pin 2 and / or the plastic connector 1 to form an elastic crimp connection.

[0050] In application, by setting the spring 5 as a mountable elastic conductive component and making its free end elastically contact the conductive area in the PIN pin 2 and / or plastic connector 1, a reliable electrical connection can be achieved without relying on rigid soldering. This elastic pressing method, in conjunction with the above-mentioned reflow soldering SMT fixing and circuit board 4 support structure, can automatically compensate for displacement deviations under conditions of high temperature, vibration and assembly tolerance, and maintain stable contact pressure, thereby significantly reducing the risk of contact failure and fatigue fracture, and solving the problem of insufficient reliability of traditional rigid electrical connections under complex automotive operating conditions.

[0051] In some embodiments, the spring 5 can be designed as a sheet, a tongue, or a multi-arm structure; its material can be an elastic conductive material such as phosphor bronze or beryllium copper; the elastic force and contact area of ​​the spring 5 need to be adjusted according to the current requirements and vibration level.

[0052] A third embodiment of the high-stability automotive high-pressure sensor packaging structure, for example Figure 1 , Figure 2 and Figure 4As shown, the difference between this embodiment and the first embodiment is that the spring 5 and the PIN pin 2 are pre-welded and fixed, and during assembly, the free end of the spring 5 is elastically pressed into the solder pad area 41 of the circuit board 4 to achieve electrical connection.

[0053] In application, the spring 5 and PIN pin 2 are pre-welded and fixed to form an integrated electrical connection assembly. During assembly, the free end of the spring 5 is elastically pressed against the solder pad area 41 of the circuit board 4. This reduces the number of solder joints and assembly steps while ensuring conductivity reliability. This method, together with the riveting and fixing of the metal hexagonal shell 3 and the supporting structure of the circuit board 4, helps to improve the overall assembly consistency and vibration resistance, and solves the problems of complex assembly and reliability fluctuation caused by multiple solder joints in the prior art.

[0054] The pre-welding method can be spot welding, laser welding or reflow welding; the contact form between the spring 5 and the pad of the circuit board 4 can be designed as surface contact or line contact.

[0055] In some embodiments, a wear-resistant or anti-oxidation coating may also be provided in the pad area 41.

[0056] A fourth embodiment of a high-stability automotive high-pressure sensor packaging structure, for example Figure 1 , Figure 2 and Figure 5 As shown, the difference between this embodiment and the first embodiment is that the circuit board 4 is provided with a floating limiting vibration isolation structure 9 in the circumferential direction. The floating limiting vibration isolation structure 9 is used to provide axial limiting and pre-tightening for the circuit board 4, and at the same time, it causes the circuit board 4 to generate a radial micro-displacement within a preset range relative to the metal hexagonal shell 3, so as to release assembly stress and / or thermal stress and reduce vibration transmission, thereby improving the connection stability under high pressure and complex working conditions, and reducing the impact of stress concentration in the metal hexagonal shell 3 on the reliability of the circuit board 4 and its solder joints.

[0057] Specifically, the floating limiting vibration isolation structure 9 includes at least three elastic limiting members 91 arranged circumferentially. The elastic limiting members 91 are disposed at the outer peripheral edge of the circuit board 4 and elastically abut against the inner wall of the metal hexagonal shell 3. Each elastic limiting member 91 has a contact portion 911 facing the inner wall of the metal hexagonal shell 3. The contact portion 911 is an arc surface and / or a chamfered surface, so as to provide axial limiting and pre-tightening for the circuit board 4, while causing the circuit board 4 to generate radial micro-displacement relative to the metal hexagonal shell 3, thereby realizing vibration isolation and stress release and improving connection stability.

[0058] In application, by setting a floating limiting vibration isolation structure 9 around the circuit board 4, the circuit board 4 can be reliably limited and pre-tightened in the axial direction. Specifically, multiple elastic limiting members 91 arranged at intervals along the circumference elastically abut against the inner wall of the metal hexagonal shell 3, and achieve flexible support through the contact form of arc surface or chamfered surface, so that micro displacement within a preset range can be generated in the radial direction, thereby effectively releasing assembly stress and thermal stress under high pressure loading, temperature change and vibration. This structure works in conjunction with the metal washer 6 fixed by three-point electric welding and the elastic electric connection method, which can significantly reduce the impact of stress concentration inside the metal hexagonal shell 3 on the reliability of the circuit board 4 and the solder joints, and solve the problem that rigid fixation of the circuit board 4 is prone to solder joint fatigue and failure in the prior art.

[0059] In some embodiments, the number of elastic limiting members 91 can be set to three or more points according to the size and vibration level, and their form can be an elastic arm, an elastic tongue, or an independent elastic member; the elastic limiting member 91 can also be integrally formed with the circuit board 4 or assembled as an independent component to adapt to different structural spaces and manufacturing process requirements.

[0060] Specifically, the elastic limiting element 91 is either a spring or a sheet 5.

[0061] Based on the above embodiments of the high-stability automotive high-pressure sensor packaging structure, a packaging method for an automotive high-pressure sensor is provided to achieve the high-stability automotive high-pressure sensor packaging structure, such as... Figure 6 As shown, the steps are as follows, implemented sequentially from S1 to S5: S1, Assemble the main structure: fit the pressure-sensing element into the metal hexagonal shell and install the sealing ring; S2. Sub-component assembly: Fix the spring and metal washer to the circuit board by reflow soldering. S3. Assembly: The pads of the strain gauge of the pressure sensing element are soldered to the pads of the circuit board through the binding wire. Then, the metal washer is soldered to the inner stepped surface of the metal hexagonal shell. Finally, the pressure sensing element is soldered to the metal hexagonal shell for fixation. S4. Install the plastic connector: Assemble the plastic connector and make the pin and the spring form an elastic electrical connection path; S5. Packaging: The metal hexagonal shell and the plastic connector are riveted together to complete the packaging.

[0062] When applying the product, the encapsulation method is implemented sequentially according to steps S1 to S5, so that pressure sensing, sealing, electrical connection and structural fixation form an orderly construction path from the inside to the outside and from function to encapsulation during the assembly process.

[0063] Specifically, in step S1, the pressure-sensing element is first fitted into the hexagonal metal shell and a sealing ring is installed simultaneously, so that the pressure-sensing element is initially positioned within the hexagonal metal shell and a first sealing interface is established, providing a reliable foundation for subsequent welding and pressure bearing; in step S2, the spring and metal gasket are fixed to the upper and lower sides of the circuit board by reflow soldering, so that the electrical connection components and structural support components are integrated at the circuit board level, ensuring assembly accuracy and consistency; in step S3, the pads of the strain gauge are first electrically connected to the pads of the circuit board by binding wire, and then the metal gasket is soldered to... The inner stepped surface of the metal hexagonal shell completes the axial positioning of the circuit board assembly. Finally, the pressure-sensing element is welded and fixed to the metal hexagonal shell, so that the pressure-bearing and sealing body is finally formed, thereby avoiding interference or damage to the completed electrical connection during the welding process. In step S4, by assembling the plastic connector and forming an elastic electrical connection path between the PIN pin and the spring, the external electrical connection can maintain reliable conduction while having elastic compensation capability. Finally, in step S5, by riveting and fixing the metal hexagonal shell and the plastic connector, all internal components are locked together in a sealed state.

[0064] By coordinating the above assembly sequence and processes, the pressure bearing path, sealing path, and electrical signal transmission path are gradually established and decoupled during the assembly process. This ensures both sealing reliability and structural strength under high-pressure conditions, and effectively releases assembly stress, thermal stress, and vibration loads through flexible electrical connections and graded fixing methods. This significantly improves the long-term stability of automotive high-pressure sensors under complex conditions and solves the problems of easily damaged electrical connections, internal stress concentration, and insufficient packaging reliability caused by unreasonable assembly sequences in existing technologies.

[0065] The technical features of the embodiments can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described.

Claims

1. A high-stability automotive high-pressure sensor packaging structure, characterized in that, Includes plastic connectors, pins, hexagonal metal shells, circuit boards, springs, metal washers, sealing rings, and pressure-sensitive components; The metal hexagonal shell is fixedly connected to the pressure-sensing element to form a pressure-bearing and sealing main structure; the circuit board is disposed inside the metal hexagonal shell and electrically connected to the pressure-sensing element; the spring is used to form an elastic electrical connection path between the circuit board and the PIN pin. The metal washer is fixed below the circuit board, the spring is fixed above the circuit board, and the metal washer is fixedly connected to the inner stepped surface of the metal hexagonal shell by welding. The sealing ring is disposed in the sealing gap between the metal washer and the metal hexagonal shell; the metal hexagonal shell and the plastic connector are fixedly connected by riveting, so that the PIN pin is led out from the plastic connector.

2. The high-stability automotive high-pressure sensor packaging structure according to claim 1, characterized in that, The hexagonal metal shell is fixedly connected to the pressure-sensing element by laser welding.

3. The high-stability automotive high-pressure sensor packaging structure according to claim 1, characterized in that, The metal gasket is fixed to the circuit board by reflow soldering SMT method; The circuit board and the spring are fixed together by reflow soldering (SMT).

4. The high-stability automotive high-pressure sensor packaging structure according to claim 1, characterized in that, The metal washer is fixedly connected to the inner stepped surface of the metal hexagonal shell by three-point electric welding.

5. The high-stability automotive high-pressure sensor packaging structure according to claim 1, characterized in that, The spring is a mountable elastic conductive component. The free end of the spring contacts the conductive area inside the PIN pin and / or the plastic connector to form an elastic crimp connection.

6. The high-stability automotive high-pressure sensor packaging structure according to claim 1, characterized in that, The spring and the PIN are pre-welded and fixed. During assembly, the free end of the spring is elastically pressed against the pad area of ​​the circuit board to achieve electrical connection.

7. The high-stability automotive high-pressure sensor packaging structure according to claim 1, characterized in that, The circuit board is provided with a floating limiting vibration isolation structure in the circumferential direction. The floating limiting vibration isolation structure is used to provide axial limiting and pre-tightening for the circuit board, while causing the circuit board to generate radial micro-displacement within a preset range relative to the metal hexagonal shell, so as to release assembly stress and / or thermal stress and reduce vibration transmission, thereby improving the connection stability under high pressure and complex working conditions, and reducing the impact of stress concentration in the metal hexagonal shell on the reliability of the circuit board and its solder joints.

8. The high-stability automotive high-pressure sensor packaging structure according to claim 7, characterized in that, The floating limiting vibration isolation structure includes at least three elastic limiting members arranged circumferentially, the elastic limiting members being disposed at the outer peripheral edge of the circuit board and elastically abutting against the inner wall of the metal hexagonal shell; Each of the elastic limiting members has a contact portion facing the inner wall of the metal hexagonal shell. The contact portion is an arc surface and / or a chamfered surface, so as to provide axial limiting and pre-tightening for the circuit board while causing the circuit board to generate radial micro-displacement relative to the metal hexagonal shell, thereby achieving vibration isolation and stress relief and improving connection stability.

9. The high-stability automotive high-pressure sensor packaging structure according to claim 1, characterized in that, The pressure-sensing element includes a stainless steel housing, a strain gauge, and a glass adhesive layer for bonding the strain gauge. The stainless steel housing has a connecting end and a sensing end; the strain gauge is bonded to the sensing end of the stainless steel housing through the glass adhesive layer and sintered and fixed; the connecting end has a connecting thread for connecting to the position to be measured; the connecting end has a drainage cavity for introducing the fluid to be measured into the vicinity of the sensing end, so that the pressure of the fluid to be measured is transmitted to the strain gauge. The sensing end extends into the hexagonal metal shell and faces the circuit board. The electrical signal of the strain gauge is led out to the circuit board through the metal washer inside the hexagonal metal shell via a binding wire.

10. A packaging method for a high-pressure sensor for vehicles, used to implement the high-stability high-pressure sensor packaging structure for vehicles as described in any one of claims 1 to 9, characterized in that, The process includes the following steps: S1, Assemble the main structure: Fit the pressure-sensing element into the metal hexagonal shell and install the sealing ring; S2. Sub-component assembly: Fix the spring and metal washer to the circuit board by reflow soldering. S3. Assembly: The pads of the strain gauge of the pressure sensing element are soldered to the pads of the circuit board through the binding wire. Then, the metal washer is soldered to the inner stepped surface of the metal hexagonal shell. Finally, the pressure sensing element is soldered to the metal hexagonal shell for fixation. S4. Install the plastic connector: Assemble the plastic connector and make the pin and the spring form an elastic electrical connection path; S5. Packaging: The metal hexagonal shell and the plastic connector are riveted together to complete the packaging.

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