Six-dimensional force sensor device based on MEMS principle and preparation method thereof

Abstract

The invention discloses a six-dimensional force sensor device based on an MEMS principle and a preparation method of the six-dimensional force sensor device. The six-dimensional force sensor device comprises an MEMS six-dimensional force sensor prepared on a silicon substrate through an MEMS technology, a PCB integrated with an ASIC chip, a force conduction column, an anti-disassembly supporting structure and a packaging structure. The MEMS six-dimensional force sensor is prepared on a silicon substrate through an MEMS technology, a steel body structure is not needed, errors and low efficiency caused by manual strain gauge mounting can be effectively improved, and the device weight and the preparation cost are reduced. The force transmission column transmits an external force / torque to the MEMS six-dimensional force sensor, the MEMS six-dimensional force sensor measures the external force / torque and converts the external force / torque into an analog electric signal, the PCB carries out amplification, filtering, demodulation, decoupling, calibration, AD / DA conversion and other processing on the analog electric signal, and a test result is output in the form of a digital signal. On one hand, the anti-disassembly supporting structure supports the packaging structure, isolates the packaging structure from the MEMS six-dimensional force sensor, and on the other hand, prevents illegal disassembly of the MEMS six-dimensional force sensor, so that the whole device works normally.

Description

Technical Field

[0001] The present invention relates to the technical field of sensors, and particularly relates to a six-dimensional force sensor device based on the MEMS principle and a preparation method thereof. Background Art

[0002] Micro Electro Mechanical System (MEMS), also known as micro-electromechanical system, includes microelectronic devices made through a series of silicon / non-silicon microfabrication process technologies. A complete MEMS often includes microsensors, micro actuators, micro mechanical structures, signal detection and control systems, etc., and can independently perform signal sensing, detection, processing, and transmission. The internal structure size is in the micron or even nanometer order of magnitude. The research and development of MEMS is related to multiple disciplinary fields such as materials science, mechanics, microelectronics, electromagnetics, and optics. Devices made by MEMS technology can be used to measure physical parameters such as force, electricity, acceleration, temperature, humidity, etc., and have the advantages of low power consumption, small volume, high response speed, high sensitivity, high integration, and high stability, and are often used as key tools for information interaction between the outside and the inside. After decades of research and development, MEMS has been widely used in important fields such as military equipment, medical devices, the automotive industry, the robotics field, and consumer electronics.

[0003] The six-dimensional force sensor, also known as the six-dimensional force / torque sensor, six-axis force sensor, and F / T sensor, is a special force sensor that can simultaneously measure three forces (FX, FY, FZ) and three torques (MX, MY, MZ) in the coordinate system (OXYZ). If the direction and point of action of the force change randomly in three-dimensional space, a six-dimensional force sensor should be used for measurement. Because the force at any point of action in space can be decomposed into three-directional components along the calibrated coordinate axis (FX, FY, FZ) and three-directional torques around the calibrated coordinate axis (MX, MY, MZ) in the calibrated coordinate system of the six-dimensional force sensor. This type of sensor is more suitable for scenarios where the reference point is far away and changes randomly, and requires higher measurement accuracy. The existing six-dimensional force implementation methods include strain, piezoelectric, capacitive, fiber optic and photoelectric. Among them, the strain type is mainly used in industrial robots and automotive testing, with the advantages of low cost and good stability, but high temperature sensitivity and limited dynamic response; piezoelectric is mainly used for impact testing and high-speed dynamic control, with the advantages of fast response and high stiffness, but static measurement is limited and charge amplification is required; micro-operation and precision instruments are used for micro-operation and precision instruments, with high sensitivity and good temperature stability, but are susceptible to interference and have complex manufacturing processes; fiber optic is used in aerospace and some harsh environments, with the advantages of strong anti-interference and high precision, and the disadvantages of high cost and complex installation; photoelectric is mainly used in biomedicine and micro-electromechanical systems, non-contact and high resolution, but it is complex in structure and sensitive to ambient light. At present, strain-type six-dimensional force sensors occupy about 76% of the entire six-dimensional force sensor market due to their low cost and good stability, but there are still the following shortcomings:

[0004] It is difficult to strike a balance between sensitivity and range: strain gauges have low sensitivity (especially metal strain gauges) and are difficult to detect tiny forces or torques (such as millinewtons). For scenarios that require high-resolution measurements (such as precision medical operations), more expensive semiconductor strain gauges or piezoelectric technology may be required. The physical deformation range of the elastomeric structure is limited, and it is difficult to take into account both high precision and a large range at the same time. If the range is exceeded, it may directly lead to plastic deformation of the elastomer or damage to the strain gauge.

[0005] Temperature drift and compensation are complex: the resistance value of the strain gauge will fluctuate with temperature, and the thermal expansion of the elastomeric material will also introduce deformation errors. Even if a temperature compensation circuit (such as a Wheatstone bridge) is used, residual drift may still occur in an environment with drastic temperature changes (such as aerospace or automotive high-temperature testing). Complex temperature compensation requires additional hardware (such as built-in temperature sensors) and algorithm support, which increases design and maintenance costs.

[0006] Cross-interference and decoupling error: Although decoupled by the calibration matrix, the elastomer may exhibit non-linear deformation under high loads or complex forces, resulting in the failure of the decoupling algorithm. For example, applying a large torque may accidentally trigger a measurement error in the axial force; the calibration accuracy directly affects the measurement result, but multi-dimensional calibration requires special equipment (such as a six-degree-of-freedom loading platform), and the calibration process is time-consuming and costly.

[0007] Limited dynamic response ability: The elastomer of the strain sensor has a large mass, resulting in a low natural frequency (usually a few hundred hertz), making it difficult to capture high-frequency dynamic force signals (such as rapid collisions or vibration analysis of a robotic arm); there is a hysteresis effect in the process from deformation to electrical signal output, which is not suitable for control scenarios with extremely high real-time requirements.

[0008] Long-term stability problems: Under long-term repeated loads, the elastomer may experience creep (slow plastic deformation) or metal fatigue, resulting in zero drift or decreased sensitivity, and it is necessary to re-calibrate regularly to maintain accuracy; the adhesive of the strain gauge may also degrade due to the environment (humidity, chemical corrosion) or mechanical stress, causing signal drift or even failure.

[0009] Installation and environmental adaptability challenges: The sensor must be rigidly connected to the load. An uneven or slightly tilted mounting surface will introduce additional torques, significantly affecting the measurement result. For example, the installation error of the end effector of a robot may cause the torque data to be distorted; electromagnetic interference (such as motor drive signals) may also affect the weak electrical signal of the strain gauge, and additional shielding measures are required; moreover, in a humid, oily or corrosive environment, insufficient protection level of the strain gauge may lead to a shortened lifespan.

[0010] Cost and maintenance complexity: Multi-dimensional calibration requires precision equipment and professional operation, increasing the usage threshold. Once the strain gauge or elastomer is damaged, it usually needs to be returned to the factory for repair or the entire sensor module needs to be replaced, and it is difficult to repair on-site. Summary of the Invention

[0011] The technical problem to be solved by the present invention is to provide a six-axis force sensor device based on the MEMS principle and its preparation method to achieve multi-dimensional force measurement with high sensitivity, high stability, and low power consumption through microfabrication technology, aiming at the deficiencies of existing strain-type six-axis force sensors in terms of sensitivity, temperature drift, dynamic response, long-term reliability, and cost.

[0012] To solve the above technical problems, the present invention provides a six-axis force sensor device based on the MEMS principle, including:

[0013] An MEMS six-axis force sensor, fabricated on a silicon substrate using MEMS technology, for measuring force and torque signals on three external axes of X, Y, and Z and converting them into analog electrical signals;

[0014] A PCB board integrated with an ASIC chip and peripheral electronic components, where the MEMS six-axis force sensor is connected to the PCB board through sensor pads, and is used to amplify, filter, demodulate, decouple, calibrate, and perform AD / DA conversion on the analog electrical signals output by the MEMS six-axis force sensor, and output digital signals;

[0015] A force conduction column, which is anodic bonded or welded to the MEMS six-axis force sensor, and is used to transfer external force or torque to the MEMS six-axis force sensor;

[0016] An anti-disassembly support structure, which is firmly connected to the PCB board, and the MEMS six-axis force sensor is isolated within the anti-disassembly support structure to prevent the MEMS six-axis force sensor from being illegally disassembled;

[0017] A flexible packaging structure, which is closely attached to the force conduction column, is used to contact with external force and conduct the external force to the force conduction column, while protecting the force conduction column and buffering external loads.

[0018] The MEMS six-axis force sensor of the present invention is completely fabricated on a silicon substrate through MEMS processes, without the need for a steel body structure, which can effectively improve the errors and low efficiency problems caused by manual mounting of strain gauges, reduce the weight and manufacturing cost of the sensor. The ASIC chip on the PCB board integrates most of the PCB board-level circuit functions and is the core component of the PCB board, making the area of the entire processing circuit significantly reduced compared to the overall area of traditional strain-type six-axis force sensors (generally including 2 - 4 PCB boards), and the number of electronic components also decreases sharply, reducing the volume and thickness of the entire six-axis force sensor, reducing the design difficulty of layout and wiring on the PCB board, reducing the weight of the entire six-axis force sensor, and thus reducing the overall power consumption of the used device;

[0019] As a further description of the above technical solution, the MEMS six-axis force sensor is a piezoresistive, resonant, or capacitive sensor, adopting piezoresistive, resonant, or capacitive principles; it is selected according to the application scenario. If strict requirements are imposed on the detection accuracy, a resonant type is preferably selected; if cost and process simplification are desired, a piezoresistive type is preferably selected.

[0020] As a further description of the above technical solution, the sensor pads are centered on the PCB board to ensure that the external forces received by the MEMS six-axis force sensor can be evenly distributed on the detection structures in different directions.

[0021] As a further description of the above technical solution, the ASIC chip and the peripheral electronic components are symmetrically arranged on the PCB board, so that after reflow soldering, there is no strain and stress on the PCB board (especially at the sensor pads), thus ensuring that the performance of the MEMS six-axis force sensor will not be affected by the deformation of the PCB circuit board.

[0022] As a further description of the above technical solution, the material of the force conduction column is metal, glass or ceramic, and it is fixedly connected to the MEMS six-axis force sensor through anodic bonding, adhesive bonding or metallization connection. Preferably, the glass material is firmly connected to the MEMS six-axis force sensor by anodic bonding, so as to accurately transmit the sensed external force / moment to the MEMS six-axis force sensor.

[0023] As a further description of the above technical solution, the material of the anti-disassembly support structure is hard ceramic or hard metal, preferably stainless steel or hard aluminum. Copper pads are prepared at the corresponding positions on the PCB board, and then the anti-disassembly support structure is firmly connected to the PCB board by reflow soldering or laser welding to protect the internal MEMS six-axis force sensor from illegal disassembly; a protruding hole for the force conduction column to protrude is provided in the center of the anti-disassembly support structure, and the protruding hole is circular or oval, and the aperture of the protruding hole matches the range of the MEMS six-axis force sensor. The anti-disassembly support structure serves as a limiting structure to prevent the MEMS six-axis force sensor from being damaged by excessive external forces.

[0024] As a further description of the above technical solution, the material of the encapsulation structure is a flexible material such as silicone, polycarbonate (PC), polyvinyl chloride (PVC) or polyimide, which is used to buffer external forces or moments and protect the force conduction column. Moreover, the encapsulation structure can be shaped and solidified according to the application scenario. For example, when used in a robot fingertip, it can be shaped according to the surface topography of the robot fingertip to achieve a perfect fit with the robot fingertip, better sense external forces and moments, and improve the detection accuracy and sensitivity of the six-axis force sensor device.

[0025] As a further description of the above technical solution, when the encapsulation structure is connected to the anti-disassembly support structure, it is also connected to the PCB circuit board, making the encapsulation more firm and conducive to improving the overall reliability.

[0026] The present invention also provides a preparation method for a six-axis force sensor device based on the MEMS principle, including the following steps:

[0027] S1. Prepare a MEMS six-axis force sensor on a silicon substrate through MEMS technology;

[0028] S2. Firmly connect the MEMS six-axis force sensor to the force conduction column by anodic bonding or welding;

[0029] S3. Solder the ASIC chip and peripheral electronic components on the PCB board, and the ASIC chip and peripheral electronic components are symmetrically arranged on the PCB board;

[0030] S4. Centrally solder the MEMS six-axis force sensor on the PCB board through the sensor pads;

[0031] S5. Solder the anti-disassembly support structure on the PCB board, isolate the MEMS six-axis force sensor within the anti-disassembly support structure, and open an extension hole on the anti-disassembly support structure for the force conduction column to extend. The aperture size of the extension hole matches the measurement range of the MEMS six-axis force sensor.

[0032] S6. Shape the encapsulation structure according to the application scenario so that the encapsulation structure can closely fit with the force conduction column.

[0033] S7. The encapsulation structure is separately connected to the anti-disassembly support structure or simultaneously connected to the anti-disassembly support structure and the PCB board.

[0034] The MEMS six-axis force sensor is prepared by MEMS technology, which has high automation, good consistency, high alignment accuracy, does not require manual chip mounting, has a mature supply chain, and can effectively overcome the disadvantage of high installation sensitivity of strain sensors. For strain-type six-axis force sensors, the smaller the volume, the more difficult it is to mount strain gauges, and the higher the price. Through MEMS technology, MEMS six-axis force sensors with consistent performance can be mass-produced, significantly reducing the preparation cost, shrinking the finished product volume, and reducing the maintenance and replacement cost, thereby promoting the application penetration of six-axis force sensors to the fingertips of robots, the execution terminals of surgical medical intelligent devices, the ends of robotic arms, etc.

[0035] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0036] The six-axis force sensor device of the present invention can overcome the limitation of low sensitivity of existing strain-type devices. For example, when the MEMS six-axis force sensor is realized by the piezoresistive effect, since the piezoresistive coefficient of P-type silicon is much larger than that of metal, the sensitivity can be effectively improved. For the MEMS six-axis force sensor using the resonant amplitude modulation principle, the sensitivity can be made even higher. By performing closed-loop control on the six-axis force sensor device and compensating in real time at different temperatures, the temperature drift is reduced. By optimizing the design of the six-axis force sensor device, the effective mass is reduced and the stiffness coefficient is increased to improve the dynamic response ability of the sensor. For example, the MEMS six-axis force sensor using the resonant principle can achieve a detection level of gigahertz. Moreover, since silicon materials do not have metal fatigue and with a reasonable amplitude design, the problems of material fatigue and strain gauge aging of traditional strain sensors can be effectively solved. Description of the Drawings

[0037] Figure 1 It is a schematic structural diagram of the six-axis force sensor device in Embodiment 1.

[0038] Figure 2 It is a layout diagram of the PCB board in Embodiment 1.

[0039] Figure 3 It is a preparation flow chart of the six-axis force sensor device in Embodiment 1.

[0040] Figure 4 It is a schematic structural diagram of the six-axis force sensor device in the second embodiment.

[0041] Reference numerals:

[0042] 100 - PCB board; 101 - ASIC chip; 102 - peripheral electronic components; 200 - silicon substrate; 300 - MEMS six-axis force sensor; 301 - sensor pad; 400 - force conduction column; 500 - anti-disassembly support structure; 600 - packaging structure. Detailed implementation manners

[0043] The present invention will be further described below in conjunction with the drawings and embodiments.

[0044] Embodiment 1

[0045] This embodiment provides a six-axis force sensor device based on the MEMS principle. As Figure 1 shown, from bottom to top are a PCB board 100, a silicon substrate 200, a MEMS six-axis force sensor 300, a force conduction column 400, an anti-disassembly support structure 500, and a packaging structure 600 in sequence.

[0046] Among them, an ASIC chip (application-specific integrated circuit chip) 101 and other peripheral electronic components 102 are soldered on the PCB board 100, which are used to amplify, filter, demodulate, decouple, calibrate, and perform AD / DA conversion on the analog electrical signals output by the MEMS six-axis force sensor 300, and output the test results in the form of digital signals after the processing is completed. The ASIC chip 101 on the PCB board 100 integrates most of the PCB board-level circuit functions and is the core device of the PCB board 100, which significantly reduces the area of the entire processing circuit compared with the overall area of traditional strain-type six-axis force sensors (usually including 2 - 4 PCB circuit boards), and also sharply reduces the number of electronic components, reduces the volume and thickness of the entire device, reduces the design difficulty of layout and wiring on the PCB board 100, reduces the weight of the entire device, and thus reduces the overall power consumption of the device in use. Moreover, the sensor pad 301 of the MEMS six-axis force sensor is centered on the PCB board 100 to ensure that the external forces received by the MEMS six-axis force sensor 300 are evenly distributed on the detection structures in different directions. The ASIC chip 101 and other peripheral electronic components 102 are symmetrically arranged on the PCB circuit board 100. As Figure 2 shown, after reflow soldering, there is no strain and stress on the PCB board 100 (especially at the sensor pad), so as to ensure that the performance of the MEMS six-axis force sensor 300 will not be affected by the deformation of the PCB board 100.

[0047] The MEMS six-axis force sensor 300 is directly fabricated on the silicon substrate 200 through the MEMS process. The principle can be selected as piezoresistive, resonant, capacitive, etc. according to requirements. If strict detection accuracy is required, the resonant type is preferred. If cost and process simplification are desired, the piezoresistive type is preferred.

[0048] The material of the force conduction column 400 is metal, glass, ceramic, etc. The connection method with the anode of the MEMS six-axis force sensor 300 can be direct bonding, adhesive bonding, metallization connection, etc. It is preferred to use glass material to achieve a firm connection with the anode of the MEMS six-axis force sensor 300 through direct bonding.

[0049] The material of the anti-disassembly support structure 500 is hard ceramic, hard metal, etc. Stainless steel or hard aluminum is preferred. Copper pads are first prepared at the corresponding positions on the PCB board 100, and a firm connection between the anti-disassembly support structure 500 and the PCB board 100 is achieved through reflow soldering or laser welding. An extension hole 501 for the force conduction column 400 to extend is left in the center of the anti-disassembly support structure 500. The shape of the extension hole 501 is circular or elliptical, and the aperture is matched with the range of the MEMS six-axis force sensor 300, serving as a limiting structure to prevent the MEMS six-axis force sensor 300 from being damaged by overload external forces.

[0050] The encapsulation structure 600 is connected to the anti-disassembly support structure 500. The material is a flexible material such as silicone, polycarbonate (PC), polyvinyl chloride (PVC), or polyimide (PI). The force conduction column 400 is protected within the encapsulation structure 600, which is used to protect the force conduction column 400 and buffer external forces / moments. The surface of the encapsulation structure 600 can be shaped according to the application scenario. For example, when used for a robot fingertip, it can be shaped and thermally cured according to the surface topography of the robot fingertip to achieve a perfect fit with the robot fingertip, better sense external forces / moments, and improve the detection accuracy and sensitivity of the device.

[0051] The preparation method of the six-axis force sensor device in this embodiment has a process as Figure 3 shown, including the following steps:

[0052] S1. Fabricate the MEMS six-axis force sensor on the silicon substrate through the MEMS process;

[0053] S2. Connect the force conduction column to the anode of the MEMS six-axis force sensor through bonding or welding;

[0054] S3. Solder the ASIC chip and peripheral electronic components on the PCB board. The ASIC chip and peripheral electronic components are symmetrically arranged on the PCB board;

[0055] S4. Centrally solder the MEMS six-axis force sensor on the PCB board through the sensor pads;

[0056] S5. Weld the anti-disassembly support structure on the PCB board, isolate the MEMS six-axis force sensor within the anti-disassembly support structure, and open an extension hole on the anti-disassembly support structure for the force conduction column to extend. The aperture size of the extension hole matches the range of the MEMS six-axis force sensor;

[0057] S6. Shape the encapsulation structure according to the application scenario, so that the encapsulation structure not only fits the application scenario but also can closely adhere to the force conduction column; for example, shape the encapsulation structure according to the surface topography of the robot fingertip to achieve a perfect fit with the robot fingertip, and at the same time can closely adhere to the force conduction column, which can better sense external forces and torques, and improve the detection accuracy and sensitivity of the six-axis force sensor device;

[0058] S7. Connect the shaped encapsulation structure to the anti-disassembly support structure by means of thermal curing.

[0059] This preparation method uses the MEMS process to prepare the MEMS six-axis force sensor, which has high automation, good consistency, high alignment accuracy, does not require manual chip mounting, and has a mature supply chain. It can effectively overcome the disadvantage of high installation sensitivity of strain gauges. For strain-type six-axis force sensors, the smaller the volume, the more difficult it is to mount strain gauges, and the higher the price. Through the MEMS process, MEMS six-axis force sensors with consistent performance can be mass-produced, greatly reducing the preparation cost, reducing the volume of the finished product, and reducing the maintenance and replacement cost. The temperature drift is compensated in real time through the ASIC chip to improve the environmental adaptability; the silicon-based structure is light in weight and high in stiffness, and the resonant principle can achieve a response at the gigahertz level. The silicon material has no metal fatigue, and the optimized amplitude design extends the service life. Thereby promoting the application penetration of six-axis force sensors to the robot fingertip, the execution terminal of surgical medical intelligent devices, the end of the robotic arm, etc.

[0060] Embodiment 2

[0061] Compared with Embodiment 1, the shaped encapsulation structure 600 is simultaneously connected to the anti-disassembly support structure 400 and the bottom PCB board 100, as Figure 4 shown, which expands the area of the encapsulation structure 600, makes the encapsulation more firm, and is beneficial to improving the overall reliability.

[0062] The above is only the best implementation mode of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, several deformations or equivalent replacements can be made to the technical solution of the present invention, and the same technical effects can also be achieved, which should also be regarded as belonging to the protection scope of the present invention.

Claims

1. A six-dimensional force sensor device based on MEMS principle, comprising: MEMS six-axis force sensor, which is prepared on a silicon substrate using MEMS technology, is used to measure the force and torque signals on the external X, Y, and Z axes and convert them into analog electrical signals; A PCB board integrated with an ASIC chip and peripheral electronic components, wherein the MEMS six-dimensional force sensor is connected to the PCB board via a sensor pad, and is used to amplify, filter, demodulate, decouple, calibrate, and perform AD / DA conversion on the analog electrical signal output by the MEMS six-dimensional force sensor, and output a digital signal; A force transmission column is connected to the MEMS six-dimensional force sensor by an anodic bonding or welding method, and is used to transmit an external force or torque to the MEMS six-dimensional force sensor; The anti-disassembly support structure is firmly connected to the PCB board, and the MEMS six-dimensional force sensor is isolated in the anti-disassembly support structure to prevent the MEMS six-dimensional force sensor from being illegally disassembled; The packaging structure is tightly fitted with the force conduction column and is used to contact with the external force and conduct the external force to the force conduction column, while protecting the force conduction column and buffering the external load.

2. The six-dimensional force sensor device according to claim 1, characterized in that: The MEMS six-dimensional force sensor is a piezoresistive, resonant or capacitive sensor.

3. The six-dimensional force sensor device according to claim 3, characterized in that: The sensor pad is centered on the PCB board.

4. The six-dimensional force sensor device according to claim 1, characterized in that: The ASIC chip and peripheral electronic components are symmetrically arranged on the PCB board.

5. The six-dimensional force sensor device according to claim 1, characterized in that: The force conduction column is made of glass, ceramic or metal and is fixed to the MEMS six-dimensional force sensor by anodic bonding, adhesive bonding or metallization connection.

6. The six-dimensional force sensor device according to claim 1, characterized in that: The material of the anti-disassembly support structure is hard ceramic or hard metal. A protrusion hole for extending the force conduction column is provided at the center of the anti-disassembly support structure. The aperture of the protrusion hole matches the measuring range of the MEMS six-dimensional force sensor.

7. The six-dimensional force sensor device according to claim 1, characterized in that: The packaging structure is made of flexible material and can be shaped according to application scenarios.

8. A method for preparing a six-dimensional force sensor device based on the MEMS principle, characterized in that: The following steps are involved: S1. Prepare a MEMS six-dimensional force sensor on a silicon substrate by using a MEMS process; S2. Firmly connect the MEMS six-dimensional force sensor to the force conduction column by anodic bonding or welding; S3, soldering the ASIC chip and peripheral electronic components on the PCB board, and the ASIC chip and peripheral electronic components are symmetrically arranged on the PCB board; S4. Solder the MEMS six-dimensional force sensor to the PCB through the sensor pad; S5. Weld an anti-disassembly support structure on the PCB board, isolate the MEMS six-dimensional force sensor in the anti-disassembly support structure, and open an extension hole in the anti-disassembly support structure for the force conduction column to extend out, and the aperture size of the extension hole matches the range of the MEMS six-dimensional force sensor; S6. Shape the packaging structure according to the application scenario so that the packaging structure and the force conduction column can fit closely; S7. The packaging structure is connected to the anti-disassembly support structure alone or is connected to the anti-disassembly support structure and the PCB board at the same time.

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