A click-resistant test equipment for circuit switch detection

Abstract

The application discloses a kind of click-resistant test equipment for circuit switch detection, belong to new energy automobile technical field, including base, fixedly installed on the top of the base top frame, and fixedly installed on the top of the base test board, the one side of the test board top is provided with the switch board for inserting the switch of measured switch, the other side of the test board top is provided with the module board for installing circuit module;The area of the switch board is installed with test structure in the top frame bottom corresponding to the switch board, and the area of the module board is installed with moving mechanism in the top frame bottom corresponding to the module board.The application realizes the through detection from macroscopic mechanical performance, thermal response to microstructure, expands the single failure judgment of existing equipment to multidimensional evaluation of failure position, failure mode and failure mechanism, and provides complete physical image support for failure analysis.

Description

Technical Field

[0001] This invention belongs to the fields of new energy vehicles and circuit durability testing technology, and in particular, it is a click resistance testing device for circuit switch testing. Background Technology

[0002] With the rapid development of the new energy vehicle industry, higher demands are being placed on the reliability of switching devices in vehicle electrical systems. New energy vehicles employ high-voltage electrical systems (typically 400V-800V), and their power battery charging and discharging circuits, high-voltage power distribution units, and on-board charging systems all rely on numerous switching devices for circuit control and protection. Unlike traditional gasoline vehicles, the switching devices in new energy vehicles need to withstand frequent high-current surges and high-voltage switching during operation. Their contact resistance stability, arc erosion resistance, and long-term mechanical durability directly affect the safe operation of the vehicle. If switching devices experience poor contact, contact welding failure, or structural failure during driving, it may lead to power interruption, battery inability to charge or discharge, or even safety accidents. Therefore, accurate and comprehensive reliability testing of switching devices has become a crucial link in the new energy vehicle industry chain.

[0003] Currently, there are various durability testing devices in the field of switch testing. An existing patent describes an online monitoring system and method for the contact resistance of circuit breaker breaks (publication number CN119024049A), which monitors the voltage and current at the break point using voltage and current transmitters, and then calculates the contact resistance, thus realizing online monitoring of the contact resistance.

[0004] In addition, the existing patented simulated load and multi-functional switch testing device (authorization announcement number CN201110886Y) simulates the overvoltage, undervoltage, and overload protection functions of the switch by setting a simulated load.

[0005] However, the aforementioned existing technologies still have the following shortcomings: First, existing switch testing equipment typically only possesses a single mechanical click function or a single electrical parameter detection function. This makes it difficult to simultaneously acquire multi-dimensional information such as the switch's mechanical performance, thermal response, and structural integrity during testing. Consequently, testers can only determine whether the switch has failed, but cannot pinpoint the location or cause of the failure, hindering in-depth analysis of the failure mechanism and failing to provide precise guidance for switch process improvements. As new energy vehicle switch devices evolve towards high voltage, high current, and high reliability, this single-dimensional testing approach can no longer meet the demands of research and development and quality control.

[0006] Second, most existing switch testing equipment uses fixed-cycle testing or relies solely on the final number of failures for judgment, lacking the ability to capture the physical state at the moment of failure. When a switch exhibits excessive contact resistance or abnormal current during testing, traditional equipment often fails to respond promptly and record thermal images and structural deformation data at the moment of failure, resulting in a lack of crucial process data to support failure mechanism analysis. For example, although CN119024049A can monitor contact resistance online, it is primarily used for monitoring the operational status of circuit breakers, rather than capturing the physical state at the moment of failure during repeated mechanical clicks.

[0007] Third, existing switch testing equipment typically uses plug-in connections or manual wiring when replacing load modules. Plug-in connections are prone to generating additional heat due to unstable contact resistance in high-current testing scenarios, interfering with the accuracy of test results. Manual wiring is inefficient, requiring several minutes or even longer for each module replacement, making it difficult to meet the rapid testing needs of multiple operating conditions and multiple load types.

[0008] In addition, the switching tests of new energy vehicles often need to be carried out under various operating conditions such as inductive loads (such as motors), capacitive loads (such as capacitor filter circuits), and resistive loads. The load switching efficiency of existing equipment has become a bottleneck in the testing process.

[0009] In summary, existing switch testing equipment has shortcomings in terms of integration of testing dimensions, ability to capture failure moments, and efficiency of load module replacement, making it difficult to meet the high reliability testing requirements of new energy vehicles for switching devices. The purpose of this invention is to provide a click-resistant testing device for circuit switch testing to solve the problems mentioned in the background art. Summary of the Invention

[0010] The purpose of this invention is to provide a click resistance testing device for circuit switch testing, so as to solve the problems mentioned in the background art.

[0011] To achieve the above objectives, the present invention provides the following technical solution: a circuit switch detection click resistance test device, comprising a base, a top frame fixedly installed above the base, and a test board fixedly installed on the top of the base, wherein a switch plate for inserting the switch under test is provided on one side of the top of the test board, and a module plate for installing circuit modules is provided on the other side of the top of the test board; A test structure is installed at the bottom of the top frame corresponding to the area of ​​the switch plate, and a moving mechanism is installed at the bottom of the top frame corresponding to the area of ​​the module plate. The test structure includes a rotary motor fixed to the bottom of the top frame, a rotary plate connected to the output shaft of the rotary motor, and a click push rod, an infrared thermal imager, and a laser speckle interferometer uniformly installed on the lower surface of the rotary plate along the circumference. The click push rod has a built-in counter for periodic counting. The electric push rod performs click tests on the switch by reciprocating extension and retraction. After the click push rod completes one period of counting, the rotary motor drives the rotary plate to move the infrared thermal imager and the laser speckle interferometer to the corresponding positions of the working switch in sequence, so as to perform thermal imaging detection and speckle interferometry detection on the switch respectively.

[0012] Furthermore: a pin cylinder is provided at the bottom of the switch board corresponding to the pin position of the switch. The pin cylinder is a metal conductive cylinder with an inner diameter that matches the outer diameter of the pin of the switch. A circuit tester is installed below the switch board, and the circuit tester is electrically connected to the pin cylinder at the bottom of the switch board through wiring.

[0013] Furthermore: a solder plate is installed below the module board, and the module board and the solder plate are respectively provided with an upper connection hole and a lower connection groove for accommodating the pins of the circuit module. The upper connection hole is a through hole that penetrates the module board, and the lower connection groove is a groove opened on the top surface of the solder plate. The upper connection hole and the lower connection groove are aligned vertically.

[0014] Furthermore, the bottom of the lower connecting groove of the solder plate is provided with an electric heating element for heating the solder, the electric heating element being a heating element embedded inside the solder plate.

[0015] Furthermore, a height push rod is installed below the solder plate, and the output end of the height push rod is fixedly connected to the bottom of the solder plate.

[0016] Furthermore, the moving mechanism includes a vertical slide rail fixedly installed at the bottom of the top frame, a horizontal slide rail slidably installed on the vertical slide rail, an electric push rod slidably installed on the horizontal slide rail, and a clamping part installed at the bottom of the electric push rod.

[0017] Furthermore: the rotating plate is disc-shaped, and the click push rod, infrared thermal imager and laser speckle interferometer are evenly distributed along the circumference of the rotating plate, with the included angle between adjacent ones being 120°.

[0018] Furthermore: the vertical slide rail and the horizontal slide rail form a two-dimensional moving platform. The electric push rod drives the clamping part to rise and fall, so that the clamping part moves to above the module plate under the drive of the vertical slide rail and the horizontal slide rail, and then falls under the drive of the electric push rod to grab or release the circuit module.

[0019] Furthermore: the height push rod drives the solder plate to rise and fall, so that when the solder plate rises, it pushes the molten solder to contact the pins of the circuit module to form a solder joint, and when it falls, it separates the solder plate from the module board.

[0020] Compared with the prior art, the present invention has the following beneficial effects: This invention involves uniformly mounting a push rod, an infrared thermal imager, and a laser speckle interferometer circumferentially on a rotating plate. These three components are sequentially aligned with the location of a switch as the plate rotates. Driven by a rotary motor, the push rod first aligns with the switch and reciprocates at a preset stroke and frequency, applying simulated mechanical stress to the switch. After a preset cycle is completed by a counter, the rotary motor drives the rotating plate to rotate, aligning the infrared thermal imager with the same switch. Utilizing the principle of infrared radiation reception, it acquires an image of the temperature distribution on the switch surface, forming a thermal image of localized temperature rise caused by abnormal contact resistance or internal defects. Subsequently, the rotary motor drives the rotating plate to rotate again, aligning the laser speckle interferometer with... The switch emits a laser onto its surface and acquires reflected speckle images. It then uses the phase change of the speckle pattern before and after loading to generate an out-of-plane displacement field distribution map. The butterfly-shaped stripe feature accurately locates structural defects such as microcracks and voids. The above three detection functions are executed sequentially on the same rotating platform, and the detection data is stored in a time-series correlation. This achieves a comprehensive detection from macroscopic mechanical properties and thermal response to microscopic structure. While completing the durability test of the switch, it also captures its weak areas when it fails. This expands the existing single failure judgment of equipment to a multi-dimensional evaluation of failure location, failure mode and failure mechanism, providing a complete physical image support for failure analysis.

[0021] This invention constructs a real-time electrical parameter monitoring loop by setting a pin cylinder at the bottom of the switch plate to mate with the switch pins, and electrically connecting a circuit tester to the pin cylinder via wiring. During the test, the circuit tester continuously collects the current, voltage, and contact resistance parameters of the switch, forming an electrical performance data stream synchronized with the mechanical click action. Simultaneously, the test structure automatically performs thermal imaging and speckle detection according to a preset cycle to periodically assess the health status of the switch. When the circuit tester detects electrical abnormalities such as contact resistance exceeding a preset threshold, current interruption, or continuous conduction, it immediately sends a trigger signal to the rotating motor. The rotating motor then drives the rotating plate to sequentially align the infrared thermal imager and laser speckle interferometer with the switch, completing thermal image acquisition and defect location at the moment of failure. Furthermore, the signal linkage between this electrical monitoring loop and the rotating detection structure upgrades the event-driven capture response mechanism, enabling failure data to no longer be limited to the final failure count statistics, but to accurately record the physical state at the moment of failure, providing crucial process data support for switch failure mechanism analysis.

[0022] This invention constructs an automated soldering-type module replacement platform by sequentially arranging a solder plate, a heating element, and a height pusher below a module board, combined with a moving mechanism. The module board and solder plate each have corresponding upper connecting holes and lower connecting slots. The lower connecting slot is filled with solder, and the heating element is embedded inside the solder plate to heat and melt the solder. When a circuit module needs to be installed, the moving mechanism drives the clamping part to grasp the circuit module and insert its pins into the upper connecting hole and then into the lower connecting slot. The heating element is energized to heat and melt the solder. The height pusher pushes the solder plate upwards to ensure full contact between the molten solder and the pins. Subsequently, the heating element... When the power is off, the solder cools and solidifies to form a welded connection. When a module needs to be replaced, the heating element reheats the solder to melt it. The height push rod drives the solder plate down to separate the pins from the solder. The moving mechanism grabs the module and removes it. Then, the new module is installed following the same steps. This achieves lower contact resistance and higher connection stability in high-current testing scenarios, avoiding interference with test results caused by additional heat generated by poor contact of the connectors. The module switching time is reduced from tens of minutes required by traditional manual wiring to several minutes, enabling the equipment to efficiently simulate various real-world operating conditions such as inductive, capacitive, and lamp loads. Attached Figure Description

[0023] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the switch board and circuit tester in this invention; Figure 3 This is a schematic diagram of the module board structure in this invention; Figure 4 This is a schematic diagram of the test structure in this invention; Figure 5 This is a schematic diagram of the internal structure of the module board in this invention; Figure 6 This is a schematic diagram of the movable structure in this invention.

[0025] Explanation of reference numerals in the attached figures: In the picture: 1. Base; 2. Test board; 21. Switch board; 211. Pin tube; 22. Module board; 221. Upper connection hole; 222. Solder board; 223. Lower connection slot; 224. Heating unit; 225. Height push rod; 23. Switch; 3. Top frame; 31. Test structure; 311. Rotary motor; 312. Rotating plate; 313. Click push rod; 314. Infrared thermal imager; 315. Laser speckle interferometer; 32. Moving mechanism; 321. Vertical slide rail; 322. Horizontal slide rail; 323. Electric push rod; 324. Clamping part; 4. Circuit tester; 41. Wiring. Detailed Implementation

[0026] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described in order to avoid obscuring the invention.

[0027] Unless otherwise defined, the directions mentioned herein, such as up, down, left, right, front, back, inside, and outside, are based on the directions shown in the figures of this invention, and are explained here together.

[0028] The connection method can be any existing method, such as bonding, welding, or bolting, depending on the actual needs.

[0029] Please see Figures 1 to 6 As shown, this embodiment provides a circuit switch detection click resistance test device, including a base 1 and a top frame 3 fixedly installed on the base 1. A test board 2 is fixedly installed on the top of the base 1. A switch board 21 and a module board 22 are respectively arranged on the left and right sides of the top of the test board 2. The switch board 21 is equipped with the switch under test 23 by plugging it in. The module board 22 is equipped with a circuit module for simulating different circuit conditions.

[0030] A test structure 31 is installed on the area of ​​the bottom of the top frame 3 facing the switch plate 21, and a moving mechanism 32 is installed on the area of ​​the bottom of the top frame 3 facing the module plate 22. The test structure 31 and the moving mechanism 32 are located on the left and right sides of the bottom of the top frame 3, respectively, corresponding to the positions of the switch plate 21 and the module plate 22, and do not interfere with each other.

[0031] The test structure 31 includes a rotary motor 311 fixedly mounted on the bottom of the top frame 3. The output axis of the rotary motor 311 is connected downward to a rotating plate 312. The rotating plate 312 is disc-shaped, and a click push rod 313, an infrared thermal imager 314, and a laser speckle interferometer 315 are uniformly mounted on its lower surface along the circumference. The click push rod 313, the infrared thermal imager 314, and the laser speckle interferometer 315 are each fixed to the lower surface of the rotating plate 312 by independent mounting brackets. Vibration damping pads are provided between each mounting bracket and the rotating plate 312 to attenuate the transmission of vibrations generated when the click push rod 313 is activated to the laser speckle interferometer 315.

[0032] During the detection process, after the click push rod 313 completes a preset cycle of clicking action, the rotary motor 311 drives the rotating plate 312 to rotate, so that the laser speckle interferometer 315 is aligned with the switch 23. At this time, the control system controls the click push rod 313 to remain stationary and delays for a predetermined time before starting the detection action of the laser speckle interferometer 315, so as to ensure that the rotating plate 312 and the laser speckle interferometer 315 are in a stable state and to avoid the vibration of the click push rod 313 affecting the detection accuracy.

[0033] The rotary motor 311 is a stepper motor, which can precisely control the rotation angle of the rotating plate 312, so that the click push rod 313, the infrared thermal imager 314 or the laser speckle interferometer 315 are aligned with the switch 23 below in sequence.

[0034] Infrared thermal imager 314 receives infrared energy radiated from the surface of switch 23 and converts it into a visualized temperature distribution image. During long-term operation testing of switch 23, when contacts become fatigued, oxidized, or loose, contact resistance increases, generating abnormal Joule heating when current flows, leading to a localized temperature rise. Infrared thermal imager 314 can capture this temperature rise and present it as a pseudo-color image, with high-temperature areas displayed in red and white, thus accurately locating the contact point where the heat source is located.

[0035] The laser speckle interferometer 315 uses coherent laser light to illuminate the surface of the switch 23, forming a speckle pattern. A small load is applied to the switch 23, causing localized minor deformation in the internal defect region due to reduced stiffness, resulting in a phase change in the speckle pattern. The system generates an out-of-plane displacement field distribution map by comparing the phase difference before and after loading. When defects such as microcracks, voids, or delamination exist inside the switch 23, the defect region exhibits characteristic butterfly-shaped or ring-shaped fringes on the interference image, thus accurately locating the position and size of the defect.

[0036] Infrared thermal imager 314 detects the electrical performance degradation of switch 23 under energized operating conditions (such as thermal anomalies caused by increased contact resistance), reflecting functional defects; laser speckle interferometer 315 detects the physical integrity damage of switch 23 under mechanical stress (such as microcracks and voids), reflecting structural defects. Combining these two methods allows for a comprehensive assessment of the failure state of switch 23, distinguishing whether the failure is caused by electrical or mechanical factors.

[0037] Second, it enables early warning and mechanism tracing of the failure process. Traditional testing can only determine whether the switch 23 has failed, while the collaborative detection of this invention can detect early anomalies: when only thermal anomalies occur without structural defects, it indicates that the switch 23 has experienced electrical performance degradation but has not yet developed into physical damage, belonging to an early stage that is repairable; when only structural defects occur without thermal anomalies, it indicates the presence of mechanical damage caused by non-electrical factors. This graded diagnostic capability provides the switch 23 with full-process data from sub-health to failure for reliability assessment.

[0038] Based on the above test results, the following improvements are recommended for the manufacturing of switch 23: Optimize the contact material and structure. The abnormal temperature rise point detected by infrared thermal imaging indicates that the contact resistance at that location is too high. For example, it is suggested to use low-resistivity, high-oxidation-resistivity materials such as silver-tin oxide or silver-nickel in the contact manufacturing process, or to add a gold or silver plating layer to the contact surface to reduce contact resistance. Simultaneously, optimize the elastic structure design of the contacts to ensure stable contact pressure after long-term pressing and prevent loosening of the contacts due to spring fatigue.

[0039] Strengthen process control in areas prone to structural defects. Microcracks and voids detected by laser speckle interferometry are typically concentrated in critical structural components, weld points, or stress concentration areas during injection molding. For example, it is recommended to optimize mold temperature and injection pressure in the manufacturing of injection molded parts such as the housing and base of switch 23 to reduce internal porosity and residual stress; and to use double-sided welding or add reinforcing structures at the connection between the pins and internal contacts to improve fatigue resistance.

[0040] A pin cylinder 211 is provided at the bottom of the switch plate 21 corresponding to the pin position of the switch 23. The pin cylinder 211 is a metal conductive cylinder, and its inner diameter matches the outer diameter of the pin of the switch 23 to enable quick insertion of the switch 23. A circuit tester 4 is installed below the switch plate 21. The circuit tester 4 is connected to the pin cylinder 211 at the bottom of the switch plate 21 through a wiring 41, thereby forming an electrical connection with the pin of the switch 23 under test.

[0041] The circuit tester 4 can monitor the electrical parameters of the switch 23, such as current, voltage, and contact resistance, in real time during the clicking process. When an abnormality is detected (such as contact resistance exceeding a preset threshold, current interruption, or continuous conduction), it can send a trigger signal to the control system.

[0042] A solder plate 222 is mounted below the module board 22. The module board 22 and the solder plate 222 are respectively provided with an upper connecting hole 221 and a lower connecting groove 223. The upper connecting hole 221 is a through hole penetrating the module board 22, and the lower connecting groove 223 is a recess formed on the top surface of the solder plate 222. The upper connecting hole 221 and the lower connecting groove 223 are aligned vertically to accommodate the pins of the circuit module. A heating element 224 is provided at the bottom of the lower connecting groove 223 of the solder plate 222. The heating element 224 is a heating resistance wire or ceramic heating element embedded inside the solder plate 222, used to heat the solder in the lower connecting groove 223.

[0043] A height push rod 225 is installed below the solder plate 222. The height push rod 225 is an electric push rod 323. Its output end is fixedly connected to the bottom of the solder plate 222 and is used to drive the solder plate 222 to rise or fall, so that the pins of the circuit module contact or separate from the solder.

[0044] The moving mechanism 32 includes a mounting plate fixedly installed at the bottom of the top frame 3. The mounting plate is horizontally positioned and fixedly connected to the lower surface of the top frame 3 by bolts. A vertical slide rail 321 is fixedly installed on the lower surface of the mounting plate. The vertical slide rail 321 extends vertically, and a horizontal slide rail 322 is slidably installed on the vertical slide rail 321. The horizontal slide rail 322 can rise and fall vertically. An electric push rod 323 is slidably installed on the horizontal slide rail 322. The electric push rod 323 can move horizontally, and its output end extends downward, with a clamping part 324 installed at its bottom.

[0045] The clamping part 324 is a pneumatic gripper, including two clamping arms arranged opposite each other. The end of the clamping arm is provided with a flexible clamping head. The flexible clamping head is made of rubber or polyurethane material. The clamping surface of the flexible clamping head is provided with a positioning groove that is adapted to the outer periphery of the circuit module pin.

[0046] During clamping, the two clamping arms close relative to each other, and the positioning groove clamps the outer periphery of the pins of the circuit module, guiding the pins of the circuit module and inserting them into the upper connection hole 221 on the module board 22.

[0047] The clamping force of the clamping part 324 is controlled by a pneumatic pressure regulating valve, which is electrically connected to the control system and is used to adjust the clamping force according to the size of the circuit module.

[0048] The clamping part 324 can be adjusted to fit the size of the switch. Currently, the size of miniature switches in automobiles and large equipment is often greater than 2 cm in length, and the length of ordinary model switches is greater than 6 cm.

[0049] Both the vertical slide rail 321 and the horizontal slide rail 322 are driven by servo motors, enabling precise positioning of the clamping part 324 at any position in the horizontal plane. The clamping part 324 is a pneumatic gripper used to grasp or release the circuit module.

[0050] The working process of this embodiment is as follows: Before starting the test, the operator sets the number of test cycles through the control system (e.g., setting each test cycle to 1000 clicks). The moving mechanism 32 is activated, and the vertical slide rail 321 and the horizontal slide rail 322 move together to move the clamping part 324 above the module board 22. The electric push rod 323 descends, and the clamping part 324 grasps the circuit module to be tested (e.g., an inductive load module, a capacitive load module, or a lamp load module) and inserts it with its pins aligned with the upper connection hole 221 on the module board 22. At this time, the pins of the circuit module pass through the upper connection hole 221 and enter the lower connection slot 223.

[0051] The control system activates the heating element 224, heating the solder in the lower connecting slot 223 to a molten state (approximately 220℃-250℃). The height push rod 225 rises, pushing the solder plate 222 upwards, ensuring full contact between the molten solder and the circuit module pins. Subsequently, the heating element 224 is de-energized, and the solder cools and solidifies naturally, forming a strong solder joint that secures the circuit module to the module board 22 and establishes an electrical connection with the test circuit below. This structure achieves a stable connection between the circuit module and the high-current test circuit through soldering, avoiding the overheating or arcing phenomena caused by unstable contact resistance under high current conditions with simple plug-in connections.

[0052] The operator inserts the switch under test 23 into the pin sleeve 211 on the top of the switch board 21. The pin sleeve 211 is connected to the circuit tester 4 via wiring 41. The circuit tester 4 is also electrically connected to the circuit module on the module board 22, forming a complete test circuit. The control system starts the test program, and the rotary motor 311 drives the rotary plate 312 to rotate, so that the click push rod 313 is aligned with the switch 23. The click push rod 313 starts to reciprocate clicking the switch 23 at a preset frequency (e.g., 20 times per minute) and stroke, and the counter records the number of clicks.

[0053] After the push button 313 completes a preset cycle (e.g., 1000 clicks), the push button 313 pauses its action. The rotary motor 311 drives the rotating plate 312 to rotate 120°, aligning the infrared thermal imager 314 with the switch 23. The infrared thermal imager 314 performs a thermal imaging scan of the switch 23, acquiring temperature distribution images of the switch 23's surface and key internal nodes. The control system compares the thermal imaging data with a preset temperature threshold. If localized overheating is detected (e.g., a contact temperature exceeding the ambient temperature by more than 30°C), the abnormal location is recorded and marked as a potential fault point.

[0054] Subsequently, the rotary motor 311 rotates another 120°, aligning the laser speckle interferometer 315 with the switch 23. The laser speckle interferometer 315 emits a laser beam onto the surface of the switch 23 and acquires the reflected speckle image. By comparing and analyzing the speckle images before and after loading (which can be combined with vacuum loading or thermal loading), an out-of-plane displacement field distribution map of the switch 23 surface can be generated. When defects such as microcracks, voids, delamination, or debonding exist inside the switch 23, discontinuous surface displacement fields will be generated at the defect locations, presenting characteristic butterfly-shaped fringes on the interference image, thereby accurately locating the defect position and size. The control system performs correlation analysis between the defect detection results and the thermal imaging results. If both temperature anomalies and structural defects occur at the same location, the location is determined to be a severe failure point.

[0055] Throughout the test, the circuit tester 4 monitors the electrical parameters of the switch 23 in real time. When the circuit tester 4 detects an abnormal current (such as current interruption or continuous current conduction) or abnormal contact resistance (such as resistance exceeding 200% of the initial value) in the switch 23, the circuit tester 4 immediately sends a trigger signal to the control system.

[0056] After receiving the trigger signal, the control system immediately pauses the action of the click pusher 313 regardless of whether the current number of clicks has reached the preset number of cycles, and sequentially starts the infrared thermal imager 314 and the laser speckle interferometer 315 according to the above process to perform thermal imaging and defect detection on the switch 23 in the abnormal state, so as to capture the physical state at the moment of failure and provide key data for failure mechanism analysis.

[0057] When a circuit module needs to be replaced to simulate different load conditions (e.g., switching from an inductive load to a capacitive load), the control system initiates a height push rod 225 to descend, separating the solder plate 222 from the module board 22. Simultaneously, the heating element 224 is activated to reheat the solder in the lower connecting groove 223 to a molten state.

[0058] The moving mechanism 32 is activated, and the clamping part 324 grasps the current circuit module, pulling its pins out of the molten solder. Subsequently, the clamping part 324 moves to the circuit module storage area, releases the current module, and grasps a new circuit module, completing the installation and soldering process following the steps in the first step. The entire process is automatically completed by the control system, eliminating the need for manual rewiring 41, enabling rapid switching between different load types, and significantly improving testing efficiency.

[0059] Control Logic Description The control system in this embodiment uses a PLC or embedded microcontroller as its core, and its control logic is as follows: Cycle setting: The operator sets the number of click cycles N (e.g., N=1000) and the maximum total number of tests M (e.g., M=100000) via the touch screen.

[0060] Main loop: The control system starts the click push rod 313, and the counter C starts to accumulate from 0. When C%N=0 (that is, the number of clicks is an integer multiple of N), the clicking is paused, and the infrared thermal imager 314 and the laser speckle interferometer 315 are started in sequence to perform detection. After recording the detection data, the clicking is resumed.

[0061] Interruption handling: The circuit tester 4 monitors electrical parameters in real time. If the contact resistance R_contact > R_threshold (preset threshold) or the current I_out_of_range, an interrupt is triggered, clicking is immediately paused, the testing process is started, and this interrupt is marked as an "abnormal event".

[0062] Automatic mold changing: When it is necessary to switch the load type, the control system automatically executes the complete process of heating the electric heating part 224 → lowering the height push rod 225 → gripping the clamping part 324 → moving the clamping part 324 → gripping the new module → installation → welding according to the preset test sequence, without the need for manual intervention.

[0063] Data association: The control system associates and stores the number of clicks, electrical parameters (resistance, current, voltage), thermal imaging images, and speckle interferometry images according to timestamps to form a complete test report.

[0064] As new energy vehicle technology continues to iterate, its voltage is gradually breaking new highs. In the charging and discharging circuit of the power battery, switches (such as contactors and relays) need to carry a continuous current of hundreds of amperes and cut off short-circuit currents of up to thousands of amperes when a fault occurs. In addition, high-voltage loads such as air conditioning compressors and PTC heaters will generate surge impacts several times the rated current at the moment of startup. As a typical inductive load, the drive motor will generate an extremely high reverse induced electromotive force at the moment of switch turn-off, which will have a strong impact on the contacts. Therefore, the quality of the switch is very important.

[0065] One point to note is the issue of motion interference affecting the infrared thermal imager 314: During testing, the mechanical action of clicking the push rod 313 may cause a slight displacement of the switch under test, affecting the focusing accuracy of the thermal image. To address this, an elastic positioning piece can be added to the switch board 21 to pre-tighten and fix the switch 23; simultaneously, a delay can be set in the control logic, delaying the thermal imaging for 0.5 seconds after the push rod 313 stops, ensuring the device under test is in a stable state.

[0066] Ambient light interference in laser speckle interferometry: Laser speckle interferometry is sensitive to ambient light, and changes in ambient light may affect detection accuracy. To address this, a light shield can be installed around the test structure 31, and a background light compensation algorithm can be integrated into the control system to collect and subtract the ambient light background before each detection.

[0067] Temperature control accuracy in soldering: The heating temperature of the heating element 224 directly affects the soldering quality. Excessive temperature may damage the circuit module, while insufficient temperature will result in inadequate solder flow. To address this, a thermocouple can be embedded inside the solder board 222 to form a closed-loop PID temperature control system, ensuring the solder temperature remains stable within a preset range (e.g., 230℃ ± 5℃).

[0068] Data management issues during multi-module testing: When testing combinations of multiple switches 23 and multiple circuit modules, a large amount of test data is generated. To address this, a database management module can be integrated into the control system to generate a unique test ID for each test combination and store all test data (click count, electrical parameters, thermal images, speckle maps) in association, supporting subsequent retrieval and export analysis based on conditions.

[0069] The issue of repeatability of the rotating plate 312: After multiple rotations, the rotating plate 312 may accumulate errors, leading to alignment deviations in the click push rod 313, the thermal imager, or the speckle interferometer. To address this, a photoelectric limit switch can be installed circumferentially on the rotating plate 312. After each rotation, zero-point calibration is performed via the photoelectric switch to ensure rotational positioning accuracy.

[0070] Through the above-described structural design, control logic, and countermeasures, the circuit switch testing equipment of this embodiment can stably and efficiently complete the full life cycle testing of 23 switches, providing reliable technical support for the quality control and failure analysis of switch products.

[0071] It should be noted that, in this document, relational terms such as "one" and "two" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, the phrase "comprising an element defined as..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0072] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A circuit switch testing device for click resistance testing, comprising a base (1), a top frame (3) fixedly installed above the base (1), and a test plate (2) fixedly installed on the top of the base (1), wherein a switch plate (21) for inserting a switch (23) under test is provided on one side of the top of the test plate (2), and a module plate (22) for installing circuit modules is provided on the other side of the top of the test plate (2), characterized in that: A test structure (31) is installed at the bottom of the top frame (3) in the area corresponding to the switch plate (21), and a moving mechanism (32) is installed at the bottom of the top frame (3) in the area corresponding to the module plate (22). The test structure (31) includes a rotary motor (311) fixed to the bottom of the top frame (3), a rotary plate (312) connected to the output shaft of the rotary motor (311), and a click push rod (313), an infrared thermal imager (314), and a laser speckle interferometer (315) uniformly installed on the lower surface of the rotary plate (312) along the circumference. The click push rod (313) has a built-in counter for periodic counting. The electric push rod (323) performs a click test on the switch (23) by reciprocating extension and retraction. After the click push rod (313) completes one periodic count, the rotary motor (311) drives the rotary plate (312) to move the infrared thermal imager (314) and the laser speckle interferometer (315) to the corresponding positions of the working switch (23) in sequence, so as to perform thermal imaging detection and speckle interferometry detection on the switch (23) respectively.

2. The click resistance testing device for circuit switch testing according to claim 1, characterized in that: The bottom of the switch plate (21) is provided with a pin tube (211) corresponding to the pin position of the switch (23). The pin tube (211) is a metal conductive tube with an inner diameter that matches the outer diameter of the pin of the switch (23). A circuit tester (4) is installed below the switch plate (21). The circuit tester (4) is electrically connected to the pin tube (211) at the bottom of the switch plate (21) through a wiring (41).

3. The click resistance testing device for circuit switch testing according to claim 1, characterized in that: A solder plate (222) is installed below the module board (22). The module board (22) and the solder plate (222) are respectively provided with an upper connection hole (221) and a lower connection groove (223) for accommodating the pins of the circuit module. The upper connection hole (221) is a through hole that penetrates the module board (22), and the lower connection groove (223) is a groove opened on the top surface of the solder plate (222). The upper connection hole (221) and the lower connection groove (223) are aligned vertically.

4. The click resistance testing device for circuit switch testing according to claim 3, characterized in that: The bottom of the lower connecting groove (223) of the solder plate (222) is provided with an electric heating part (224) for heating the solder. The electric heating part (224) is a heating element embedded inside the solder plate (222).

5. The click resistance testing device for circuit switch testing according to claim 3, characterized in that: A height push rod (225) is installed below the solder plate (222), and the output end of the height push rod (225) is fixedly connected to the bottom of the solder plate (222).

6. The click resistance testing device for circuit switch testing according to claim 1, characterized in that: The moving mechanism (32) includes a vertical slide rail (321) fixedly installed at the bottom of the top frame (3), a horizontal slide rail (322) slidably installed on the vertical slide rail (321), an electric push rod (323) slidably installed on the horizontal slide rail (322), and a clamping part (324) installed at the bottom of the electric push rod (323).

7. The click resistance testing device for circuit switch testing according to claim 1, characterized in that: The rotating plate (312) is disc-shaped, and the click push rod (313), infrared thermal imager (314) and laser speckle interferometer (315) are evenly distributed along the circumference of the rotating plate (312), and the included angle between adjacent ones is 120°.

8. The click resistance testing device for circuit switch testing according to claim 6, characterized in that: The vertical slide rail (321) and the horizontal slide rail (322) form a two-dimensional moving platform. The electric push rod (323) drives the clamping part (324) to rise and fall, so that the clamping part (324) moves to above the module plate (22) under the drive of the vertical slide rail (321) and the horizontal slide rail (322), and falls down under the drive of the electric push rod (323) to grab or release the circuit module.

9. The click resistance testing device for circuit switch testing according to claim 5, characterized in that: The height push rod (225) drives the solder plate (222) to rise and fall, so that when the solder plate (222) rises, the molten solder contacts the pins of the circuit module to form a solder joint, and when it falls, the solder plate (222) separates from the module board (22).

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