Magnetic switch detection device and detection method

Abstract

The invention relates to the technical field of magnetic switches, in particular to a magnetic switch detection device and method. The magnetic switch detection device comprises a base which is provided with an accommodating cavity used for fixing a magnetic switch; the at least three conductive columns are arranged in the accommodating cavity, correspond to a plurality of binding posts of the magnetic switch respectively and are electrically connected with the binding posts; the driving module comprises a pressure applying mechanism and is used for enabling a binding post of the magnetic switch to be in close contact with the conductive column through vertical pressure so as to form a conduction path; and the adjustable current source is connected with the conductive column and is used for inputting a preset current waveform to the magnetic switch. Through dynamic waveform regulation and control of the adjustable current source and precise pressure control of the driving module, poor contact and current limitation in traditional detection are avoided, meanwhile, the taking and placing efficiency of the magnetic switch is remarkably improved, and extreme working condition simulation and multi-dimensional performance evaluation of the magnetic switch are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of magnetic switches, and particularly relates to a magnetic switch detection device and a detection method. Background Art

[0002] As one of the core components of an automotive starting system, the reliability of a magnetic switch is directly related to the normal starting and driving safety of a vehicle. During the ignition process of an automobile, the magnetic switch drives the contact to close by controlling an electromagnet mechanism, and transmits the high current of the battery to the starter, thereby starting the engine. Once there are defects such as poor contact of the contacts, contact welding of the contacts, or failure of the electromagnet mechanism in the magnetic switch, it will cause the vehicle to fail to start, and even lead to safety hazards such as circuit short - circuit and overheating. Therefore, the pre - factory detection of magnetic switches is an essential link in the quality control of automotive parts.

[0003] Currently, the conventional detection methods for magnetic switches in the industry mainly focus on power - on function verification, that is, simply testing whether it can conduct normally through power - on. However, such methods have the following significant defects: Single test condition: Only the conduction performance under rated current is verified, and it is impossible to simulate extreme working conditions that may occur in actual applications (such as large - current impact during engine cold start, long - time overload operation, etc.).

[0004] Lack of multi - parameter collaborative detection: Existing technologies do not comprehensively evaluate the mechanical properties of magnetic switches (such as the retraction speed and rebound force of the telescopic iron core) and thermal stability (such as the change of contact resistance of contacts under high and low temperature environments), resulting in potential defects being difficult to detect in a timely manner.

[0005] Insufficient detection efficiency and accuracy: Traditional manual item - by - item testing relies on the experience of operators, is prone to introducing errors due to uneven pressure control or poor contact, and cannot achieve automated data recording and analysis.

[0006] In addition, magnetic switches need to withstand the influence of complex environments (such as high temperature in the engine compartment, low temperature in extremely cold regions) and current fluctuations during actual use. Existing detection equipment generally lacks the ability to simulate the environment, resulting in a significant deviation between the factory test results and the actual working conditions.

[0007] In summary, developing a magnetic switch testing device and method that can simulate multi - working - condition conditions and integrate current - temperature - mechanical property collaborative detection has become an urgent need to improve product reliability and reduce automotive safety hazards. Summary of the Invention

[0008] (1) The technical problem to be solved by the present invention is that the existing magnetic switch detection device lacks a dynamic current regulation and contact pressure stabilization mechanism, making it difficult to simulate actual extreme working conditions (such as instantaneous large current impact, continuous overload), resulting in the inability to accurately evaluate the overload capacity and contact reliability of the product. At the same time, a single current waveform cannot cover the requirements of complex working conditions, and the detection results are seriously out of touch with the actual application scenarios, restricting the quality control efficiency and product safety.

[0009] (2) Technical solution To solve the above technical problems, the present invention provides a magnetic switch detection device, including a base, a driving module and an adjustable current source. The base is provided with a receiving cavity for fixing the magnetic switch; at least three conductive posts are arranged in the receiving cavity, corresponding to and electrically connected to a plurality of wiring posts of the magnetic switch respectively. The driving module includes a pressure application mechanism for making the wiring posts of the magnetic switch in close contact with the conductive posts through a vertical pressure to form a conduction path. The adjustable current source is connected to the conductive posts and is used for inputting a preset current waveform to the magnetic switch.

[0010] Through the precise alignment design of the three conductive posts and the wiring posts of the magnetic switch, and the vertical pressure control of the driving module, it is ensured that the contact surface pressure is evenly distributed, eliminating the poor contact problem caused by traditional manual clamping, and significantly improving the conduction stability and test repeatability. Through the dynamic waveform regulation function of the adjustable current source, a preset pulse, step or overload current is directly input to the magnetic switch to accurately simulate extreme working conditions such as instantaneous large current impact and continuous overload, and verify its electrical strength and overload resistance in the real scenario. Further combined with the fixed structure of the base receiving cavity and the fast conduction path of the conductive posts, the clamping process of the magnetic switch is simplified, and rapid picking and placing and stable detection can be achieved without complex positioning operations. The synergistic effect of the above technical solutions breaks through the limitations of single current working conditions, uncontrollable contact pressure and low test efficiency in traditional detection, and provides a multi-dimensional and accurate evaluation method for the reliability of magnetic switches.

[0011] According to an embodiment of the present invention, the pressure application mechanism includes a lifting cylinder and an upper pressing block connected to the lifting cylinder. The pressing surface of the upper pressing block is provided with a relief hole, and the position of the relief hole corresponds to the telescopic part of the magnetic switch for accommodating the movement of the telescopic part when applying pressure. Through the rigid driving design of the lifting cylinder and the upper pressing block, a constant and controllable vertical pressure is provided for the magnetic switch, avoiding the random error of manual pressure application, and ensuring that the contact pressure between the wiring post and the conductive post is always within the safety threshold. Through the precise adaptation of the relief hole to the telescopic part of the magnetic switch, an interference-free space is reserved for the movement of the telescopic iron core during the pressure application process, eliminating the test error caused by mechanical collision, and at the same time ensuring the free movement of the telescopic mechanism to simulate the real working state.

[0012] An elastic component is provided at the bottom of the conductive post. The elastic direction of the elastic component is consistent with the direction of the vertical pressure, and is used to buffer the contact pressure between the conductive post and the terminal of the magnetic switch. By utilizing its elastic buffering characteristics in the vertical direction, it can adaptively adjust the contact pressure, absorb the instantaneous impact energy during the pressing process, avoid the pressure damage to the terminal of the magnetic switch caused by rigid contact, and compensate for the uneven contact surface caused by machining tolerances or assembly deviations.

[0013] According to an embodiment of the present invention, the base includes a cylindrical structure, and the inner cavity of the cylindrical structure forms the accommodation cavity, and the shape of its inner wall is in imitation matching with the outer wall of the magnetic switch; Through the design of the imitation inner wall of the cylindrical structure, it is precisely attached to the outer wall of the magnetic switch, forming a physical limit and rapid positioning mechanism, avoiding the contact deviation caused by displacement during the test process, and enhancing the clamping stability at the same time.

[0014] The cylindrical structure is a temperature control structure, and a temperature adjustment unit is integrated inside, which is used to control the heating or cooling of the test environment temperature of the magnetic switch.

[0015] By actively controlling heating or cooling, the test environment of the magnetic switch is adjusted to a preset high temperature (such as 85°C), low temperature (such as -40°C) or constant temperature state, accurately simulating real working conditions such as high temperature in the vehicle engine compartment and cold start in extremely cold regions, and verifying the contact conduction, material thermal expansion adaptability and long-term thermal stability of the magnetic switch at extreme temperatures.

[0016] According to an embodiment of the present invention, an observation window is provided on the side wall of the cylindrical structure. The observation window is located on the operator side and is used to observe the alignment state and contact situation between the terminal of the magnetic switch and the conductive post in real time. Through the directional layout and transparent material design of the side wall observation window, the operator can directly visually observe the contact interface between the terminal of the magnetic switch and the conductive post, calibrate the alignment deviation in real time and verify the contact tightness, avoiding problems such as poor contact or repeated disassembly and adjustment caused by blind operation in traditional detection.

[0017] According to an embodiment of the present invention, the magnetic switch detection device further includes: A central control device; A sensor group, including: A mechanical sensor, which is used to detect the retraction force of the retractable iron core of the magnetic switch; A speed sensor, which is used to detect the retraction speed of the retractable iron core; A temperature sensor, which is used to monitor the real-time temperature of the magnetic switch; The sensor group is communicatively connected to the central control device, and the central control device is also communicatively connected to the adjustable current source and the temperature control structure, and is configured to dynamically adjust the current output and temperature parameters according to the sensor feedback data.

[0018] Through the real-time data acquisition and feedback mechanism of multi-sensor fusion, the mechanical sensor accurately captures the change in the retraction force of the telescopic iron core, the speed sensor synchronously records the dynamic response of the retraction speed, and the temperature sensor continuously monitors the temperature rise curve of the magnetic switch to form a multi-dimensional performance data chain; combined with the closed-loop control logic of the central control device, the sensor data is analyzed in real time and the output waveform of the adjustable current source (such as automatically reducing the current amplitude according to the temperature rise) and the temperature setting of the temperature control structure (such as triggering cooling according to abnormal retraction force) are dynamically adjusted to achieve adaptive optimization of the test conditions; further, through the correlation modeling of current-temperature-mechanical parameters, the performance degradation law of the magnetic switch under extreme working conditions (such as the retraction delay after the contact is oxidized due to high temperature) is quantified, providing data support for reliability life prediction. The above technical solution upgrades the traditional single electrical detection to the collaborative test of electro-thermal-mechanical multi-physical fields, solves the problems of isolated data, adjustment lag and insufficient failure mode analysis in the traditional method, and significantly improves the detection accuracy and the comprehensiveness of product evaluation.

[0019] According to an embodiment of the present invention, an installation groove is provided on the inner side wall of the avoidance hole of the upper pressing block, and the sensor assembly is disposed in the installation groove; the extending direction of the installation groove is consistent with the stroke direction of the telescopic member of the magnetic switch, so that the detection range of the sensor assembly covers the entire stroke of the telescopic member.

[0020] Through the design of the consistency between the installation groove and the stroke direction of the telescopic member, it is ensured that the detection axis of the sensor assembly is completely parallel to the moving track of the telescopic iron core, eliminating the measurement error caused by the angle deviation, and at the same time covering the full stroke dynamic response of the telescopic member from full retraction to full extension; by embedding the sensor assembly in the installation groove on the side wall of the avoidance hole, the occupation or mechanical interference of the external sensor on the test space is avoided, and the overall structural strength of the upper pressing block is maintained; the problems of measurement deviation, structural strength weakening and space interference caused by the traditional external sensor are solved, and the double improvement of high-precision detection and device reliability is realized, providing a stable hardware basis for the synchronous acquisition of multi-parameters under complex working conditions.

[0021] According to an embodiment of the present invention, a limiting groove is provided on the pressing surface of the upper pressing block, and the contour of the limiting groove matches the upper contour of the housing of the magnetic switch; When the upper pressing block is pressed down, the limiting groove and the inner wall of the cylindrical structure jointly form a circumferential limit for the magnetic switch.

[0022] Through the precise matching design of the limiting groove and the contour of the magnetic switch housing, the magnetic switch is automatically guided to the preset alignment point during the downward pressing of the upper pressing block, eliminating the position deviation during manual clamping and ensuring the initial contact accuracy between the terminal and the conductive column. Further, in combination with the cooperative limiting effect of the limiting groove and the inner wall of the cylindrical structure, a circumferential constraint on the magnetic switch housing is formed while applying vertical pressure, preventing horizontal displacement or rotational deviation caused by electromagnetic force or mechanical vibration during the test and ensuring the uniformity of the pressure distribution on the contact surface. Through the composite control mechanism of circumferential limiting and vertical pressure, the micro-motion friction of the magnetic switch caused by thermal expansion or electromagnetic shock is suppressed under extreme working conditions such as high temperature and high current, avoiding the aggravation of oxidation or wear on the contact surface. The above design breaks through the limitation of only relying on single vertical pressure in traditional detection, realizes multi-dimensional clamping stability control, provides structural guarantee for high-precision and high-reliability testing, and at the same time significantly reduces the misjudgment rate and the risk of equipment loss caused by displacement deviation.

[0023] According to an embodiment of the present invention, the magnetic switch detection device further includes: A cabinet, inside which a cooling device is provided for cooling the temperature control structure and the magnetic switch; A central control panel of the central control device is provided on the outer surface of the cabinet for inputting operation instructions and displaying parameters.

[0024] Through the coordinated regulation of the highly efficient cooling device integrated in the cabinet and the temperature control structure, the temperature of the magnetic switch and the cylindrical structure is rapidly reduced after high-temperature testing, shortening the test cycle interval, improving the detection efficiency, and at the same time avoiding the interference of residual heat on subsequent test data. Combining the external layout of the central control panel and the integrated interaction design, the operator can directly monitor the current waveform, temperature curve and sensor data in real time through the panel and dynamically adjust the test parameters (such as current step size, temperature control target value), realizing the full-process closed-loop control of "detection - regulation - analysis".

[0025] An embodiment of the present invention also provides a magnetic switch detection method, which uses the above magnetic switch detection device for detection, and includes the following steps: S1. Apply a vertical pressure to the magnetic switch through the pressure application mechanism of the drive module to make its terminal in close contact with the conductive column to form a conduction path; S2. Input an initial current value to the magnetic switch through the adjustable current source, where the initial current value is 50%-80% of its rated current, and maintain the first preset duration to record the initial conduction state; S3. Gradually increase the current value in preset steps, and maintain each current value for the second preset duration, and monitor the conduction state and response time of the magnetic switch; S4. Determine whether the failure condition is met or the preset limit current threshold is reached: If contact fusing or conduction interruption is detected, it is determined as a failure and the current value at this time is recorded as the failure current value; If there is no failure and the limit threshold is not reached, return to step S3 to continue increasing the current; S5. When the current reaches the limit threshold and the magnetic switch is not failed, repeat steps S3 to S4 until all preset current step tests are completed; S6. Generate an overload capacity evaluation parameter for the magnetic switch based on the failure current value and the limit threshold.

[0026] Furthermore, the above magnetic switch detection method can be specifically extended to the following steps: S1. Adjust the test environment of the magnetic switch to the first target temperature through the temperature control structure and maintain it for a preset duration to stabilize the temperature; S2. Apply a vertical pressure to the magnetic switch through the drive module so that its terminal is in close contact with the conductive column to form a conduction path; S3. Input an initial current value to the magnetic switch through the adjustable current source, and the initial current value is 50%-80% of its rated current, and collect the following data in real time through the sensor group: The retraction speed and retraction force of the telescopic iron core; The real-time temperature of the magnetic switch; The conduction state and response time; S4. Gradually increase the current value in preset steps, each current level is maintained for a second preset duration, and at each current level, synchronously adjust the temperature of the temperature control structure to multiple target temperature gradients, and repeat the data collection in step S3; S5. Terminate the current test stage when any of the following failure conditions is detected: The retraction force attenuation exceeds the preset threshold; The retraction speed exceeds the safe range; The temperature exceeds the rated limit or conduction is interrupted; S6. Switch to the next target temperature gradient and repeat steps S3-S5 until all temperature and current combination tests are completed; S7. Analyze the correlation between the mechanical performance, thermal stability and overload capacity of the magnetic switch based on the multi-temperature-current coupling data, and generate a comprehensive evaluation report.

[0027] Through the dynamic waveform regulation of the adjustable current source, the precise pressure control of the drive module, and the multi-sensor collaborative detection mechanism, a comprehensive performance evaluation of the magnetic switch under extreme current, temperature, and mechanical loads is achieved. The adjustable current source accurately simulates large current shocks and continuous overload conditions to verify the electrical strength; the pressure control mechanism ensures uniform contact surface pressure and eliminates poor contact; the multi-sensors collect force, speed, and temperature data in real time, and combined with the environmental simulation ability of the temperature control structure, reveal the failure modes of the magnetic switch under complex working conditions. Through structural optimization (such as cylindrical profiling limit and avoidance hole design) and intelligent feedback control, the detection efficiency, accuracy, and reliability are significantly improved, providing an efficient and multi-dimensional solution for product quality control and life prediction.

[0028] (3) Beneficial effects of the present invention: Through the dynamic waveform regulation of the adjustable current source and the precise pressure control of the drive module, while avoiding poor contact and current limitations in traditional detections, the pick-and-place efficiency of the magnetic switch is significantly improved, realizing the simulation of extreme working conditions and multi-dimensional performance evaluation of the magnetic switch. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0030] Figure 1 Schematic three-dimensional structure diagram of the magnetic switch detection device provided by an embodiment of the present invention; Figure 2 Schematic three-dimensional structure diagram of three independent detection modules on the operation table board provided by an embodiment of the present invention; Figure 3 Schematic three-dimensional structure diagram of an independent detection module provided by an embodiment of the present invention; Figure 4 For Figure 3 Schematic three-dimensional structure diagram of the second perspective; Figure 5 For Figure 3 Top view schematic diagram; Figure 6 Schematic three-dimensional structure diagram of the assembled state of the guide block and the conductive column provided by an embodiment of the present invention; Figure 7 Schematic three-dimensional structure diagram of the conductive column provided by an embodiment of the present invention; Figure 8 Schematic three-dimensional structure diagram of the magnetic switch provided by an embodiment of the present invention.

[0031] Icon: 1. Base; 11. Cylindrical structure; 111. Observation window; 12. Accommodation cavity; 2. Conductive column; 21. Elastic component; 22. Guide block; 3. Magnetic switch; 31. Terminal; 32. Telescopic iron core; 4. Pressure application mechanism; 41. Lifting cylinder; 42. Upper pressing block; 421. Avoidance hole; 422. Installation groove; 423. Limiting groove; 5. Sensor group; 10. Cabinet; 101. Central control panel; 102. Cooling device; 103. Operating table board. Detailed implementation manners

[0032] In order to more clearly understand the above objects, features and advantages of the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation manners. Without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present invention. Specific embodiment: As Figures 1 to 7 shown, this embodiment provides a magnetic switch detection device, which is mainly used for the product quality detection of the magnetic switch 3 (as Figure 8 shown). Its overall adopts a modular design, including a cabinet 10, an independent detection module, an adjustable current source, a central control device and a cooling device 102. The cabinet 10 serves as the main frame of the device and adopts a split design. The main body is welded by cold-rolled steel plates and the surface is sprayed with an anti-static coating to improve durability. The operating table board 103 is arranged on the side of the operator for the convenience of the operator to operate. An independent detection module is fixed in the center of the table top, and the central control panel 101 is embedded in the side cabinet on the opposite side. This panel is an industrial-grade touch screen, integrating parameter setting, data visualization and alarm functions, and physical buttons (such as emergency stop buttons, power switches, etc.) are equipped below to ensure the convenience of operation. The inside of the side cabinet adopts a layered layout. The cooling device 102 is installed on the upper layer, including a semiconductor refrigeration module and a liquid cooling circulation pipeline, which is used to quickly reduce the temperature of the detection module and the magnetic switch 3; the adjustable current source is fixed on the lower layer and is connected to the conductive column 2 of the detection module through a shielded cable, and the outer layer of the cable is covered with a high-temperature resistant sheath to cope with the high-current working condition. The power management unit and the data acquisition module are integrated in the cabinet below the operating table board 103, and the strong and weak electric cables are arranged through the partition wire grooves to avoid signal interference.

[0034] As Figure 1 and Figure 2As shown in the figure, there are three groups of independent detection modules on the operation table board 103. Each group of detection modules can be controlled and operated independently, and each includes a base 1, a drive module and a corresponding adjustable current source. The base 1 is composed of an annular base embedded in the operation table board 103 and a cylindrical tubular structure 11 connected thereto. The inner cavity of the tubular structure 11 forms a receiving cavity 12, and the inner wall shape thereof is in imitation matching with the outer wall of the magnetic switch 3 to be measured (for example, when the outer diameter of the magnetic switch 3 is Φ50mm, the inner diameter of the tubular structure 11 is designed as Φ50.2mm, with a 0.2mm assembly gap reserved), ensuring automatic alignment after the magnetic switch 3 is placed and avoiding manual adjustment deviation. The tubular structure 11 is a temperature control structure, and a temperature adjustment unit is integrated in its wall, including a flexible heating film embedded in the inner wall (power density 2W / cm², heating range from normal temperature to 150°C), a semiconductor refrigeration sheet attached to the outer wall (minimum refrigeration temperature -40°C), and a PT100 platinum resistance temperature sensor uniformly distributed on the inner wall. Closed-loop temperature control is realized through linkage with the central control device by a PID controller, and the accuracy reaches ±1°C.

[0035] Further, an observation window 111 is provided on the side wall of the tubular structure 11, which is located on the side directly facing the operator. It can be made of double-layer tempered glass (argon gas is filled in the middle for heat insulation), and an anti-fog coating is applied on the inner side to cope with the dew condensation problem in high and low temperature tests. Millimeter-scale scale graduations can also be provided at the edge of the window for quantifying the offset distance between the terminal 31 of the magnetic switch 3 and the conductive column 2, assisting the operator to quickly calibrate or locate faults.

[0036] There are three conductive columns 2 in the receiving cavity 12, which are distributed in a 120° ring shape, corresponding to the power supply terminal 31, the start terminal 31 and the ignition terminal 31 of the magnetic switch 3 respectively. The conductive column 2 is made of high-conductivity gold-plated copper material (the surface coating thickness ≥5μm), the column diameter is Φ8mm, and the height can be adaptively adjusted according to the compression amount of the elastic component 21.

[0037] As Figure 6 and Figure 7 shown in the figure, an elastic component 21 is provided at the bottom of the conductive column 2, including a spring and a guide block 22: Spring: It adopts a stainless steel helical compression spring, and the elastic direction is consistent with the vertical pressure direction. The maximum compression stroke is 10mm when compressed, which is used to buffer the contact pressure and compensate for the assembly tolerance between the magnetic switch 3 and the conductive column 2; Guide block 22: It is made of POM engineering plastic, embedded in the installation groove 422 of the conductive column 2, and is provided with a vertical guide groove to limit the conductive column 2 to move only in the vertical direction, preventing poor contact or local overvoltage caused by skew.

[0038] The adjustable current source adopts a modular programmable DC power supply (such as Keysight N8900 series), and is connected to the conductive column 2 through a high-temperature resistant shielded cable. The specific functions include: Current waveform generation: Pulse current: The peak current can reach 200A, simulating the large current impact during vehicle cold start; Step current: Gradually increasing by 10A / step to 200% of the rated current, with each step maintained for 30 seconds to test the continuous overload capacity; Fluctuating current: Superimposing a random fluctuation of ±15% of the rated current (frequency 0.1 - 10Hz) to simulate the scenario of unstable in - vehicle grid voltage.

[0039] Parameter adjustment: Current amplitude (continuously adjustable from 0 - 100A), rise / fall time (settable from 1ms - 10s), duration (user - defined); Over - current protection threshold (automatically cutting off the current), over - heat alarm (based on the feedback of temperature sensors).

[0040] Inter - lock control: Communicating with the central control device, automatically switching the current mode according to the test stage (such as low - temperature pre - cooling, high - temperature loading); Receiving sensor data in real - time (such as over - temperature rise limit), dynamically adjusting the output current to avoid device damage.

[0041] The driving module includes a pressure - applying mechanism 4, which is used to make the terminal 31 of the magnetic switch 3 in close contact with the conductive column 2 through vertical pressure to form a conduction path; As Figures 3 to 5 shown, the pressure - applying mechanism 4 includes a lifting cylinder 41 and an upper pressure block 42 rigidly connected thereto. The lifting cylinder 41 adopts a servo electric cylinder, which is vertically fixed to the operation table board 103 through a guide rail to ensure that the pressure - applying direction is not skewed. The pressing surface of the upper pressure block 42 is provided with an avoidance hole 421, the aperture of which is 1 - 2mm larger than the outer diameter of the telescopic iron core 32 of the magnetic switch 3 (for example, when the iron core is Φ10mm, the aperture is Φ12mm), and the depth penetrates the upper pressure block 42, which is used to completely accommodate the movement of the telescopic iron core 32 during pressure application, avoiding jamming or wear caused by mechanical interference.

[0042] A limit groove 423 is opened in the center of the pressing surface of the upper pressure block 42, and its contour is in imitation match with the upper flange of the magnetic switch 3 housing (such as a square, circular or special - shaped groove), and the width is 0.5 - 2mm larger than the housing flange, ensuring that the magnetic switch 3 is automatically guided to the preset alignment point during pressing; When the upper pressure block 42 presses down, the limit groove 423 and the inner wall of the cylindrical structure 11 form circumferential limitation, restricting the horizontal displacement and rotational offset of the magnetic switch 3 (clearance ≤0.1mm), ensuring that the contact surface between the terminal 31 and the conductive column 2 is facing each other.

[0043] The installation groove 422 is located on the inner side wall of the avoidance hole 421 and is of a U-shaped groove structure. The extending direction is parallel to the stroke direction of the telescopic part of the magnetic switch 3. The 5-piece sensor group is fixed in the installation groove 422 by snap fasteners or screws. Its detection end faces the axis of the telescopic iron core 32, and the detection range covers the full stroke (e.g., 0 - 20 mm) of the iron core from being fully retracted (initial position) to being fully extended (working position). A cable channel is provided at the bottom of the installation groove 422. The sensor signal wires are connected to the central control device through this channel to avoid external interference.

[0044] Cooperating working mechanism: Pressing process: The lifting cylinder 41 drives the upper pressing block 42 to press down. The limiting groove 423 guides the accurate positioning of the magnetic switch 3, and the avoidance hole 421 provides an interference-free moving space for the telescopic iron core 32. Pressure control: A pressure sensor (range 0 - 1000 N, accuracy ±1% FS) is built into the cylinder, and it feeds back the pressure value to the central control device in real time to form a pressure closed-loop control (e.g., setting the target pressure at 200 N ± 5 N).

[0045] The sensor group 5 specifically includes a mechanical sensor, a speed sensor, and a temperature sensor, which are respectively used to detect the retraction force, retraction speed, and real-time temperature of the telescopic iron core 32 of the magnetic switch 3. The types, detection principles, and installation positions of each sensor are as follows: The mechanical sensor can be a piezoelectric force sensor (such as Kistler 9203 type) or a strain gauge force sensor (such as HBM U9C). It is embedded in the installation groove 422 on the inner side wall of the avoidance hole 421 of the upper pressing block 42. The detection end is aligned with the axis of the telescopic iron core 32 to monitor the dynamic force value during the retraction process in real time.

[0046] The speed sensor can be a laser displacement sensor (such as Keyence IL-100) or a magnetic encoder (such as Renishaw RESOLUTE). In this embodiment, it is a laser sensor: By emitting a laser beam and receiving the reflected light, it calculates the displacement change based on the time of flight (ToF) or phase difference, and then differentiates to obtain the speed; It is arranged in parallel with the mechanical sensor in the installation groove 422, the detection direction is parallel to the stroke of the telescopic iron core 32, covering the full 0 - 20 mm stroke, and the speed resolution is 0.1 mm / s.

[0047] The temperature sensor can be a thermocouple (type K, range -40°C to 1250°C) or an infrared temperature sensor (such as Optris CTlaser); In this embodiment, it is an infrared sensor: It receives the infrared radiation energy on the surface of the magnetic switch 3 and converts the temperature through the Stefan-Boltzmann law. It is attached to the inner wall of the installation groove 422 near the terminal 31 area, without contacting the measured part, ensuring a non-destructive testing process.

[0048] The sensor group 5 is connected to the central control device through a shielded cable or a wireless module (such as ZigBee). The sampling rate is 1 kHz, and the data is transmitted in real time to the central control panel 101 for display.

[0049] Based on the above magnetic switch detection device, this embodiment further provides a method for detecting the magnetic switch 3. Through temperature regulation, pressure control, multi-stage current loading, and multi-sensor collaborative detection, a multi-faceted performance evaluation of the magnetic switch 3 is realized. The specific steps are as follows: Step S1: Ambient temperature adjustment and stabilization Target temperature setting: The test environment is adjusted to the first target temperature (such as -40°C, 25°C, or 85°C) through the temperature control unit (heating film and semiconductor refrigeration sheet) of the cylindrical structure 11.

[0050] Temperature stability control: In the heating mode, the heating film adjusts the power with a PID control algorithm to ensure that the temperature fluctuation ≤ ±1°C; In the refrigeration mode, the semiconductor refrigeration sheet and the liquid cooling cycle work together, and the flow rate of the ethylene glycol solution is 5 L / min to accelerate heat dissipation; The temperature sensor (PT100) monitors the ambient temperature in real time. After reaching the target value, it is maintained for at least 5 minutes to ensure the uniform temperature of the magnetic switch 3.

[0051] Step S2: Vertical pressure application and conduction path establishment Pressure application: The servo electric cylinder of the driving module drives the upper pressing block 42 to press down at a constant speed (10 mm / s), and the target pressure is 200 N ± 5 N; The limiting groove 423 cooperates with the inner wall of the cylindrical structure 11 to limit the horizontal displacement of the magnetic switch 3 (clearance ≤ 0.1 mm).

[0052] Conduction path optimization: The elastic component 21 (spring stiffness 50 N / mm) at the bottom of the conductive column 2 is compressed until the contact resistance ≤ 1 mΩ; The avoidance hole 421 provides an interference-free moving space for the telescopic iron core 32 to avoid mechanical jamming.

[0053] Step S3: Initial current loading and data acquisition Initial current input: The adjustable current source outputs the initial current (such as 50% of the rated current), and the waveform is a steady-state direct current for 30 seconds.

[0054] Synchronous acquisition of sensor data: Mechanical sensor: Record the initial value of the retraction force of the telescopic iron core 32 (such as 200 N); Velocity sensor: Calculate the retraction speed based on the laser displacement signal (such as 10 mm / s); Temperature sensor: Monitor the temperature change of the magnetic switch 3 (e.g., rising from 25°C to 30°C); Conduction state: Detect the loop resistance through a high-precision ammeter and voltmeter (response time ≤ 10 ms).

[0055] Step S4: Stepwise current increase and temperature gradient switching Current increase logic: Increase the current step by step at 10 A / step (e.g., 50 A → 60 A → 70 A), and maintain each step for 30 seconds; The adjustable current source supports transient switching (rise time ≤ 1 ms) to avoid current fluctuation interference with the test.

[0056] Temperature gradient adjustment: Synchronously switch the temperature gradient when loading each level of current (e.g., switch from 25°C to -40°C or 85°C); The temperature control unit completes the temperature transition within 2 minutes. The heating film operates at full power in the high-temperature stage, and the cooling sheet and liquid cooling cooperate to cool down in the low-temperature stage.

[0057] Step S5: Dynamic failure determination and test termination Failure determination conditions: Retraction force attenuation > 20% (e.g., 200 N → 160 N): Determine as spring fatigue or mechanical wear; Retraction speed exceeds ±15% of the rated value (e.g., when the rated value is 10 mm / s, the speed > 11.5 mm / s or < 8.5 mm / s): Determine as abnormal electromagnetic response; Temperature > 150°C or conduction interruption (resistance > 10 Ω): Determine as contact welding or overheating failure.

[0058] Protection mechanism trigger: Immediately cut off the current and start the cooling device to cool down at full power (rate 10°C / min); The central control panel 101 triggers an audible and visual alarm and records the current, temperature, and sensor data at the moment of failure.

[0059] Step S6: Full temperature-current combination traversal test Test matrix design: Temperature gradient: -40°C, 25°C, 85°C; Current steps: 50%, 100%, 150%, 200% of the rated current.

[0060] Automation loop logic: Switch the temperature in the preset order (e.g., low temperature → normal temperature → high temperature), and complete all current step tests at each temperature; The single cycle takes about 45 minutes and supports multi-batch continuous testing.

[0061] Step S7: Comprehensive Evaluation and Report Generation Data Preprocessing: Outlier Removal: Smooth the data curve using moving average filtering (window size of 10 sampling points); Normalization: Normalize the force (N), speed (mm / s), and temperature (°C) to the range [0, 1] for correlation analysis.

[0062] Mechanical Property Analysis: Force-Current Relationship Modeling: Plot the curve of the retraction force versus current at different temperatures and calculate the slope ΔF / ΔI. If the slope > 0.5 N / A, it is determined that the spring stiffness has abnormal attenuation; Speed Consistency Statistics: Calculate the standard deviation of the speed at the same current level. If the standard deviation > 10% (e.g., when the rated speed is 10 mm / s, the fluctuation > 1 mm / s), it is determined that the electromagnetic mechanism response is unstable.

[0063] Thermal Stability Evaluation: Calculation of Temperature Rise Rate: Record the time Δt for the contact temperature to rise from the initial value to the failure threshold, and calculate ΔT / Δt. If the rate > 5 °C / s at high temperatures, it indicates insufficient heat dissipation design; Analysis of Thermal Hysteresis Effect: Compare the difference in retraction force at the same current during the heating and cooling processes. If the difference > 15%, it is determined that the thermal expansion coefficient of the material does not match.

[0064] Quantification of Overload Capacity: Extraction of Failure Current Threshold: Record the failure current values at different temperatures (e.g., 180 A at -40 °C, 150 A at 85 °C), fit a quadratic polynomial model of "temperature - failure current", and predict the failure risk at untested temperature points; Cyclic Life Test: Conduct repeated overload tests on non-failed samples (e.g., cycling at 150% of the rated current), record the number of cycles when the force decays to 80% of the initial value, and estimate the average life.

[0065] Analysis of Failure Mode Correlation: Multi-parameter Cross-validation: The simultaneous occurrence of "force attenuation + rapid temperature rise" at high temperatures → Contact oxidation leads to an increase in contact resistance; "Speed delay + sudden force drop" at low temperatures → Lubrication failure or brittle fracture of the material.

[0066] Verification of Root Cause: Combine microscopic observations (such as SEM analysis) to confirm the failure mode (such as contact welding, crack propagation).

[0067] Report Generation and Output: Key Parameter Table: Failure current threshold, temperature rise rate, force attenuation rate; Trend Curve Graph: 3D surface of temperature - current - force, waveform of speed - time; Failure Analysis: Root cause, impact level (fatal / serious / general); Improvement Suggestions: Material optimization (such as high - temperature alloy springs), structural improvement (such as enhanced heat dissipation design).

[0068] Interactive Analysis: The central control panel 101 supports data annotation, curve superposition and comparison, and exports reports in PDF / Excel format.

[0069] Example Application Examples Scenario 1: Low - temperature cold start test (-40°C) Test Procedure: Set the temperature to -40°C, initial current 50A (50% of the rated 100A), and increase step - by - step to 200A; The mechanical sensor detects that the retraction force drops suddenly from 250N to 180N (attenuation of 28%), triggering the failure determination; Analysis Results: Mechanical Properties: ΔF / ΔI = 0.7N / A (> the threshold value of 0.5N / A), the low - temperature brittleness of the spring causes a decrease in stiffness; Improvement Suggestions: Replace the spring material with low - temperature toughness (such as silicon - manganese alloy).

[0070] Scenario 2: High - temperature overload durability test (85°C) Test Procedure: Set the temperature to 85°C, continuously apply a current of 150A (150% of the rated 100A); The temperature sensor monitors that the contact temperature rises to 162°C, and the speed sensor detects that the retraction speed drops by 40%; Analysis Results: Thermal Stability: The temperature rise rate ΔT / Δt = 4°C / s, the oxidation of the contact causes an increase in resistance; Failure Mode: The oxide layer of the silver contact thickens at high temperature, and the retraction resistance increases; Improvement Suggestions: Change the contact plating to an antioxidant material (such as silver tin oxide).

[0071] The above are all the preferred embodiments of this application. It does not limit the protection scope of this application accordingly. Therefore, all equivalent changes made according to the structure, shape, and principle of this application should be covered within the protection scope of this application.

Claims

1. A magnetic switch detection device, characterized in that, Comprising: A base provided with a receiving cavity for fixing a magnetic switch; At least three conductive posts disposed in the receiving cavity, respectively corresponding to and electrically connected to a plurality of connection posts of the magnetic switch; A driving module including a pressure applying mechanism for making the connection posts of the magnetic switch in close contact with the conductive posts through a vertical pressure to form a conduction path; An adjustable current source connected to the conductive posts for inputting a preset current waveform to the magnetic switch.

2. The magnetic switch detection device according to claim 1, wherein: The pressure applying mechanism includes a lifting cylinder and an upper pressing block connected to the lifting cylinder. An avoidance hole is provided on the pressing surface of the upper pressing block, and the position of the avoidance hole corresponds to the telescopic part of the magnetic switch for accommodating the movement of the telescopic part when applying pressure; An elastic component is provided at the bottom of the conductive post, and the elastic direction of the elastic component is the same as the direction of the vertical pressure for buffering the contact pressure between the conductive post and the connection post of the magnetic switch.

3. The magnetic switch detection device according to claim 2, wherein The base includes a cylindrical structure, and the inner cavity of the cylindrical structure constitutes the receiving cavity, and the inner wall shape thereof is in imitation matching with the outer wall of the magnetic switch; The cylindrical structure is a temperature control structure, and a temperature adjustment unit is integrated inside for heating or cooling control of the test environment temperature of the magnetic switch.

4. The magnetic switch detection device according to claim 3, wherein An observation window is provided on the side wall of the cylindrical structure, and the observation window is located on the operator's operation side.

5. The magnetic switch detection device according to claim 3 or 4, characterized in that, Further comprising: A central control device; A sensor group including: A mechanical sensor for detecting the retraction force of the telescopic iron core of the magnetic switch; A speed sensor for detecting the retraction speed of the telescopic iron core; A temperature sensor for monitoring the real-time temperature of the magnetic switch; The sensor group is communicatively connected to the central control device, and the central control device is further communicatively connected to the adjustable current source and the temperature control structure for dynamically adjusting the current output and temperature parameters according to the sensor feedback data.

6. The magnetic switch detection device according to claim 5, wherein: An installation groove is provided on the inner side wall of the avoidance hole of the upper pressing block, and the sensor assembly is disposed in the installation groove; The extending direction of the installation groove is the same as the stroke direction of the telescopic member of the magnetic switch, so that the detection range of the sensor assembly covers the entire stroke of the telescopic member.

7. The magnetic switch detection device according to claim 5, wherein: A limiting groove is provided on the pressing surface of the upper pressing block, and the contour of the limiting groove matches the upper contour of the housing of the magnetic switch; When the upper pressing block is pressed down, the limiting groove and the inner wall of the cylindrical structure jointly form a circumferential limit for the magnetic switch.

8. The magnetic switch detection device according to claim 5, wherein Further comprising: A cabinet, and a cooling device is provided inside the cabinet for cooling the temperature control structure and the magnetic switch; A central control panel of the central control device is provided on the outer surface of the cabinet for inputting operation instructions and displaying parameters.

9. A magnetic switch detection method, characterized in that, Using the magnetic switch detection device according to any one of claims 1 to 8 for detection, comprising the following steps: S1. Through the pressure applying mechanism of the driving module, apply a vertical pressure to the magnetic switch to make its connection posts in close contact with the conductive posts to form a conduction path; S2. Input an initial current value to the magnetic switch through the adjustable current source, where the initial current value is 50%-80% of its rated current, and maintain it for a first preset duration to record the initial conduction state; S3. Gradually increase the current value in preset steps, maintain each level of current value for a second preset duration, and monitor the conduction state and response time of the magnetic switch; S4. Determine whether the failure condition is met or the preset limit current threshold is reached: If the contact is detected to be fused or the conduction is interrupted, it is determined as a failure and the current value at this time is recorded as the failure current value; If there is no failure and the limit threshold is not reached, return to step S3 to continue increasing the current; S5. When the current reaches the limit threshold and the magnetic switch does not fail, repeat steps S3 to S4 until all preset current step tests are completed; S6. Generate an overload capacity evaluation parameter for the magnetic switch based on the failure current value and the limit threshold.

10. A method for detecting a magnetic switch, characterized in that The detection using the magnetic switch detection device according to any one of claims 5 to 8 includes the following steps: S1. Adjust the test environment of the magnetic switch to the first target temperature through the temperature control structure, and maintain it for a preset duration to stabilize the temperature; S2. Apply a vertical pressure to the magnetic switch through the drive module to make its terminal tightly contact with the conductive column to form a conduction path; S3. Input an initial current value to the magnetic switch through the adjustable current source, where the initial current value is 50%-80% of its rated current, and collect the following data in real time through the sensor group: The retraction speed and retraction force of the telescopic iron core; The real-time temperature of the magnetic switch; The conduction state and response time; S4. Gradually increase the current value in preset steps, maintain each level of current for a second preset duration, and synchronously adjust the temperature of the temperature control structure to multiple target temperature gradients at each level of current, and repeat the data collection in step S3; S5. Terminate the current test stage when any of the following failure conditions is detected: The retraction force attenuation exceeds the preset threshold; The retraction speed exceeds the safe range; The temperature exceeds the rated limit or the conduction is interrupted; S6. Switch to the next target temperature gradient, and repeat steps S3-S5 until all temperature and current combination tests are completed; S7. Analyze the correlation between the mechanical properties, thermal stability and overload capacity of the magnetic switch based on the multi-temperature-current coupling data, and generate a comprehensive evaluation report.

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