A glue coating and curing control system and method based on anomaly detection

Abstract

The application discloses a kind of based on abnormality detection's glueing solidification control system and method, comprising: heating to plate piece;Adopt non-contact temperature measurement mode to collect plate piece surface temperature, obtain first temperature;According to first temperature and the heat conduction characteristic of plate piece and glue, the internal temperature of glue is calculated, and second temperature is obtained;The temperature difference of first temperature and second temperature is calculated, the fluctuation value of first temperature is calculated, and fluctuation value, second temperature, temperature difference are compared with corresponding preset threshold value respectively, whether there is temperature anomaly according to comparison result is judged;According to the determination result, whether to adjust heating parameter is selected, then return to execute step S1, until solidification is completed.The real-time temperature of glue inside is accurately calculated by using plate piece surface temperature, plate piece thermal conductivity and plate piece thickness and other parameters, accurate temperature measurement is realized, physical damage caused by existing destructive detection method to plate piece and glue layer is avoided, and the continuity of production process is guaranteed.

Description

Technical Field

[0001] This invention relates to the field of adhesive curing process technology in automobile manufacturing, and in particular to an adhesive curing control system and method based on anomaly detection. Background Technology

[0002] In the automotive manufacturing industry, adhesive curing is a crucial step in the body manufacturing process. Spot welding sealants, vibration damping adhesives, and structural adhesives are widely used for the connection and sealing of various body components. The curing quality directly affects the structural strength, sealing performance, and overall noise, vibration, and acoustic roughness performance of the vehicle. Adhesive curing typically requires heating the panels and adhesive layers to a specific temperature range and maintaining this temperature for a certain period to allow the adhesive to fully cross-link and cure, thereby achieving the required bond strength.

[0003] Currently, traditional processes mainly use resistance heating or ordinary electromagnetic heating to heat the boards, indirectly regulating the board temperature by controlling the heating power. Some processes use a constant temperature heating stage for auxiliary heating, setting fixed heating power and heating time, lacking a dynamic adjustment mechanism. Regarding temperature monitoring, existing technologies mainly employ the following methods: First, they do not perform direct temperature measurement, but only indirectly determine whether the adhesive has reached the curing temperature by controlling parameters such as heating power and heating time; second, they use contact temperature measurement methods, inserting thermocouples into the board or adhesive layer for temperature measurement, which is a destructive test; a few solutions use temperature sensors to measure the surface temperature of the board.

[0004] However, the existing technologies described above have the following problems: 1. Existing heating control methods can only control the heating power and cannot accurately determine the actual temperature of the board surface and the inside of the adhesive. Heating parameter settings rely on experience, which can easily lead to insufficient or excessive curing of the adhesive. 2. Contact temperature measurement methods are destructive and can damage the board and adhesive layer, affecting the continuity of the production process. 3. Existing technologies can only monitor the surface temperature of the board and do not consider heat conduction losses. They cannot calculate the actual temperature inside the adhesive, which can easily lead to a "false pass" phenomenon where the surface temperature meets the standard but the internal adhesive has not reached the ideal curing temperature, affecting product quality. Summary of the Invention

[0005] To address the technical problems existing in the background art, this invention proposes a coating curing control system and method based on anomaly detection.

[0006] This invention proposes a method for controlling adhesive curing based on anomaly detection, comprising: S1. Heat the sheet metal to raise its temperature; S2. The surface temperature of the board is collected using a non-contact temperature measurement method to obtain the first temperature; S3. Based on the first temperature and the thermal conductivity characteristics of the board and the adhesive, calculate the internal temperature of the adhesive to obtain the second temperature; S4. Calculate the temperature difference between the first temperature and the second temperature, calculate the fluctuation value of the first temperature, compare the fluctuation value, the second temperature, and the temperature difference with the corresponding preset thresholds, and determine whether there is a temperature abnormality based on the comparison results. S5. Based on the judgment result, select whether to adjust the heating parameters, and then return to step S1 until curing is complete.

[0007] Preferably, in step S1, a high-frequency electromagnetic coil is used to heat the plate.

[0008] Preferably, S1 specifically involves: supplying power to a high-frequency electromagnetic coil; the high-frequency electromagnetic coil converting electrical energy into an alternating electromagnetic field; the alternating electromagnetic field acting on the plate to generate eddy currents inside the plate; and the eddy currents causing the plate to heat up.

[0009] Preferably, step S1 further includes: obtaining the material of the board and the type of adhesive, setting an initial value for the heating parameters according to the material of the board and the type of adhesive, and the high-frequency electromagnetic coil heating the board according to the initial value.

[0010] Preferably, step S2 specifically involves: activating the infrared temperature sensor and aligning it with the adhesive coating area of ​​the board; the infrared temperature sensor receiving infrared radiation emitted from the surface of the adhesive coating area of ​​the board; the infrared temperature sensor generating a temperature signal based on the infrared radiation; and outputting the first temperature based on the temperature signal.

[0011] Preferably, step S3 specifically involves: obtaining the thermal diffusivity, specific heat capacity, and density of the board at a first temperature, and calculating the thermal conductivity of the board; obtaining the thickness of the board; and, based on the first temperature, the thermal conductivity of the board, and the thickness of the board, calculating the internal temperature of the adhesive using a heat conduction model to obtain the second temperature.

[0012] Preferably, the step of calculating the temperature inside the adhesive based on the heat conduction model to obtain the second temperature specifically involves: obtaining the temperature gradient of the adhesive-coated area of ​​the board, calculating the heat flux density of the adhesive-coated area of ​​the board based on the thermal conductivity of the board and the temperature gradient, and calculating the temperature inside the adhesive based on the first temperature, the heat flux density, the thickness of the board and the thermal conductivity of the board to obtain the second temperature.

[0013] Preferably, step S4 specifically involves: acquiring multiple first temperatures, calculating the difference between every two first temperatures as a fluctuation value, comparing the fluctuation value with a first preset threshold in the preset thresholds to obtain a first comparison result; comparing the second temperature with a second preset threshold in the preset thresholds to obtain a second comparison result; calculating the temperature difference between the first temperature and the second temperature, comparing the temperature difference with a preset temperature difference threshold in the preset thresholds to obtain a third comparison result; and determining whether there is a temperature anomaly based on the first comparison result, the second comparison result, and the third comparison result.

[0014] Preferably, step S5 specifically involves: obtaining a determination result; if the determination result indicates that there is no temperature abnormality, maintaining the current heating parameters and returning to step S1; if the determination result indicates that there is a temperature abnormality, adjusting the current heating parameters, returning to step S1, and triggering an abnormality alarm and an abnormality timer; if the temperature abnormality has been eliminated after returning to step S1, clearing the abnormality timer and continuing to execute step S1; if the temperature abnormality has not been eliminated when the abnormality timer reaches a preset duration, automatically stopping heating.

[0015] This invention also provides an adhesive curing control system based on anomaly detection. Applying the aforementioned adhesive curing control method, the system includes: a heating module, a temperature measurement module, a data processing module, a control module, and an alarm module. The heating module is used to perform high-frequency electromagnetic heating on the board to raise its temperature. The temperature measurement module is used to acquire a first temperature on the surface of the board using a non-contact temperature measurement method. The data processing module is used to calculate the internal temperature of the adhesive based on the first temperature and the thermal conductivity characteristics of the board and the adhesive, obtain a second temperature, and calculate the temperature difference between the first and second temperatures. The first temperature, the second temperature, and the temperature difference are compared with corresponding preset thresholds, and the comparison results are used to determine whether a temperature anomaly exists. The control module receives the determination result from the data processing module. If a temperature anomaly exists, it sends an instruction to the heating module to adjust the heating parameters; otherwise, it sends an instruction to the heating module to maintain the current heating parameters and an alarm instruction to the alarm module. The alarm module receives the alarm instruction from the control module and performs an audible and visual alarm.

[0016] In this invention, by combining non-contact infrared thermometry with a temperature calculation mechanism based on a thermal conduction model, the real-time internal temperature of the adhesive is accurately calculated using parameters such as the surface temperature, thermal conductivity, and thickness of the board. This avoids physical damage to the board and adhesive layer caused by destructive testing methods such as inserting thermocouples or performing vehicle-mounted tests, ensuring the continuity of the production process. Simultaneously, by accurately identifying the internal temperature of the adhesive, the ideal curing temperature can be precisely controlled, avoiding false acceptance and ensuring product quality. By comparing the first temperature, the second temperature, and the temperature difference between them with corresponding preset thresholds, dynamic adjustment of heating parameters is selected, achieving closed-loop temperature control based on anomaly detection. This avoids interference from factors such as ambient temperature and differences in board material on the curing temperature, ensuring the adhesive curing temperature remains consistently stable within the ideal range. This helps prevent insufficient or over-curing, thereby guaranteeing the sealing and bonding strength of the adhesive. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of the adhesive curing control system based on anomaly detection proposed in this invention. Figure 2 This is a flowchart of the adhesive curing control method based on anomaly detection proposed in this invention. Detailed Implementation

[0018] Reference Figure 1 This invention provides an adhesive curing control system based on anomaly detection. The system integrates heating, temperature measurement, calculation, control, and alarm functions. It has a clear structure and can be directly adapted to existing adhesive application stations (such as the front cover adhesive heating station in an OEM). The specific components include: a heating module, a temperature measurement module, a data processing module, a control module, and an alarm module.

[0019] The heating module includes a high-frequency electromagnetic coil, an electromagnetic controller, and a power supply. The electromagnetic controller is connected to the power supply, receiving AC power at the industrial frequency. The output of the electromagnetic controller is connected to the high-frequency electromagnetic coil, which surrounds the adhesive application area of ​​the automotive panel (non-contact, with a spacing of 5-10mm). The heating module converts the industrial frequency AC power into 20-40kHz high-frequency AC power, generating a high-frequency electromagnetic field through the high-frequency electromagnetic coil. This induces eddy currents in the panel, causing it to heat up. Receiving commands from the control unit, the module adjusts the operating frequency and heating time to achieve precise heating.

[0020] The temperature measurement module includes an infrared temperature sensor (infrared thermal imager), a mounting bracket, and a calibration unit. The infrared temperature sensor is fixed above the adhesive application station via the mounting bracket, with the lens aimed at the adhesive application area of ​​the board. The installation height is adjustable (110-130mm), and the angle is adjustable (65°-90°). The calibration unit is connected to the infrared temperature sensor and is used to correct for the influence of emissivity and ambient temperature on the temperature measurement accuracy. The temperature measurement module is used to capture infrared radiation from the board surface in real time and output surface temperature data (i.e., the initial temperature). The system generates a thermal image of the temperature field and transmits it to the data processing module.

[0021] The data processing module includes a data receiving unit, a thermal conductivity calculation unit, a temperature comparison unit, and a data storage unit. The data receiving unit receives the first temperature transmitted by the temperature measurement module. The thermal conductivity calculation unit calls the preset material parameters ( Calculate the internal temperature of the glue (i.e., the second temperature). The temperature comparison unit will , The temperature data is compared with a preset threshold to determine if any temperature anomalies exist. The data storage unit records all temperature data, performs calculations, and handles anomaly information. The data processing module receives, processes, calculates, and compares the temperature data, providing data support for anomaly detection and closed-loop control.

[0022] The control module includes a PLC controller, an instruction output unit, and a feedback receiving unit. The PLC controller receives the judgment results transmitted by the data processing module. If an abnormal temperature is detected, it sends an alarm command to the alarm module through the instruction output unit, and simultaneously sends a parameter adjustment command to the heating module. If no abnormal temperature is detected, it maintains the current heating parameters, synchronously controls the operation of the entire system, and coordinates the work of each module.

[0023] The alarm module includes an audible and visual alarm and a control panel display unit. The alarm module receives alarm commands from the control module, triggering an audible and visual alarm (sound intensity ≥80dB, flashing red light), and simultaneously displays the abnormal location, abnormal type, and abnormal data on the control panel to alert staff for timely handling.

[0024] Based on the above system settings, such as Figure 2 The present invention also provides a method for controlling the curing of adhesive coating based on anomaly detection, specifically including the following steps: S1. Heat the sheet metal to raise its temperature. This includes the following two stages: Phase 1: Before heating begins, the material information of the workpiece to be processed (e.g., aluminum alloy, steel plate, etc.) and the type of adhesive used in the current process (e.g., EVA, PUR hot melt adhesive, etc.) are first obtained. Since different workpiece materials have different electromagnetic properties and thermal conductivity, and different adhesive types also have their own curing temperature windows, the initial values ​​of the heating parameters of the high-frequency electromagnetic coil need to be preset according to the workpiece material and adhesive type. These initial values ​​specifically include the initial operating frequency of the high-frequency electromagnetic coil and the initial heating time. The operating frequency of the high-frequency electromagnetic coil is adjustable between 20-40kHz. Setting these initial values ​​ensures that the workpiece can heat up to the basic temperature conditions required for adhesive curing within a certain time.

[0025] Phase Two: After heating begins, power is supplied to the high-frequency electromagnetic coil. The electromagnetic controller rectifies the industrial frequency AC (220V) into DC, and then inverts it into high-frequency AC at 20-40kHz. When the high-frequency current passes through the high-frequency electromagnetic coil, a high-frequency electromagnetic field is generated around the coil. This high-frequency electromagnetic field is a type of alternating electromagnetic field. When the metal plate is placed in this magnetic field, the change in the magnetic field induces a closed loop current (eddy current) inside the plate. The plate's own resistance is used to convert the eddy current into heat energy (heat calculation formula: Q=I²Rt, where Q is the heat generated by the eddy current, I is the eddy current current, R is the resistance of the plate conductor, and t is the heating time), achieving uniform heating of the plate itself.

[0026] Throughout the heating process, the high-frequency electromagnetic coil continuously heats the board according to the initially set working frequency and heating time, gradually raising the board temperature to the base temperature required for the adhesive to cure, thus providing a heat source for the cross-linking and curing reaction of the adhesive.

[0027] S2. Compared to traditional temperature measurement methods that use thermocouples or vehicle-mounted tests to verify the accuracy of heating parameters, which can damage the board and adhesive layer, this step uses a non-contact infrared temperature sensor (preferably an infrared thermal imager) to measure the surface temperature of the adhesive-coated area of ​​the board in real time, obtaining the initial temperature and avoiding damage to the board and adhesive layer caused by contact temperature measurement. The specific implementation is as follows: Install the infrared temperature sensor above the adhesive coating station, adjusting the installation height, spot diameter, and measurement angle (refer to OEM application parameters: height 110-130mm, spot diameter 7-10mm, measurement angle 65°-90°), align it with the adhesive-coated area of ​​the board, capture the infrared radiation emitted from the board surface in real time, convert the invisible temperature field into a visual thermal image, and output real-time surface temperature data. (i.e., the first temperature).

[0028] Since different materials have different surface emissivity, the emissivity of the plate surface directly affects the measurement accuracy of the infrared temperature sensor. Therefore, during the process of generating a temperature signal based on infrared radiation, the temperature signal can be calibrated and corrected using emissivity. By adjusting the emissivity parameter, the influence of the surface emissivity difference on the temperature measurement accuracy can be eliminated, ensuring the accuracy of the output signal. The specific calibration process is as follows: Before the actual temperature measurement, a constant temperature heating stage is used as a reference. A known reference temperature is set, and the infrared temperature sensor is aligned with the constant temperature heating stage for measurement. The deviation between the infrared thermometer reading and the reference temperature is compared, and the emissivity parameter is adjusted accordingly to make the measured value as close as possible to the reference value until the measurement error is controlled within the allowable range.

[0029] In this embodiment, experimental data (as shown in Table 1 below) demonstrates that calibrating the infrared temperature sensor can correct the influence of emissivity (E) on temperature measurement accuracy, ensuring that the surface temperature measurement error is controlled within ±2℃.

[0030] Table 1. Parameter calibration results of the infrared temperature sensor

[0031] Table 1 above illustrates that, under the same reference temperature, when the emissivity is adjusted from 0.45 to 0.10, the infrared thermometer reading changes significantly from approximately 130℃ to 168℃. Therefore, accurate emissivity calibration is necessary for different board materials and surface conditions. The measurement error of the calibrated infrared temperature sensor can be controlled within ±2℃ (the three sets of measurement errors in Table 1 are 1.0℃, 0.5℃, and 1.2℃, respectively), verifying the feasibility and measurement accuracy of the infrared temperature measurement scheme provided in this embodiment in the adhesive application environment.

[0032] S3. Due to the difference in thermal conductivity between the surface temperature of the board and the internal temperature of the adhesive (the surface temperature is affected by ambient heat dissipation and is lower than the internal temperature), the actual curing temperature of the adhesive cannot be reflected solely by the surface temperature. Therefore, based on Fourier's law of thermal conductivity, and according to the first temperature... Based on the thermal conductivity characteristics of the board and the adhesive, the internal temperature of the adhesive is calculated to obtain the second temperature. Specifically, it includes the following sub-steps: S31. Obtain the thermophysical parameters of the material. Get the sheet metal at the first temperature thermal diffusivity Specific heat capacity and density Thermal diffusivity Specific heat capacity reflects the rate at which heat is transferred to a material when its temperature changes. Density reflects a material's ability to store heat. This reflects the mass per unit volume of the material. These three parameters are the basic inputs for calculating thermal conductivity, and all of them change with temperature. Therefore, it is necessary to consider the first temperature. The specific values ​​are obtained from the parameter data at the corresponding temperature.

[0033] S32, Calculate thermal conductivity Based on the obtained board and glue at the first temperature Below , , , , and Calculate the thermal conductivity of the sheet metal The calculation formula is as follows (1): in, The thermal conductivity of the material at temperature T is (W / (m·K)). The thermal diffusivity (m) of the material at temperature T 2 / s), The specific heat capacity of the material at temperature T is (J / (kg·K)). The density of the material at temperature T (kg / m³) 3 ).

[0034] Will Substituting into equation (1), we can obtain the thermal conductivity of the plate. .

[0035] S33. Obtain the thickness d of the adhesive-coated side of the board. The board thickness is an important parameter that determines the path length of heat transfer from the board surface to the interior of the adhesive. It directly affects the calculation of the temperature gradient and the estimation of the internal temperature in heat conduction calculations.

[0036] S34. Calculate the heat flux density based on the obtained temperature gradient. Temperature gradient This refers to the rate of change of temperature in space, reflecting the magnitude of the driving force for heat transfer. During heat conduction, heat always flows from high-temperature regions to low-temperature regions; the greater the temperature gradient, the stronger the driving force for heat transfer.

[0037] Based on the thermal conductivity of the plate and temperature gradient The heat flux density of the glued area of ​​the board is calculated using the following formula (2): in, This indicates the temperature gradient (°C / m), which is the rate of temperature change from the surface of the board to the interior of the adhesive; the negative sign indicates that the direction of heat flow is opposite to the direction of the temperature gradient.

[0038] S35, Calculate the internal temperature of the adhesive During the heat transfer from the surface of the board to the interior of the adhesive, the thermal resistance of the board itself must be overcome. The higher the heat flux density q and the thicker the board d, the lower the thermal conductivity of the board. The smaller the value, the greater the temperature difference between the surface of the board and the interior of the adhesive. This is the second temperature representing the internal temperature of the adhesive. The calculation formula is as follows (3): By using the above formula (3) and combining experimental data for calibration (e.g., when the constant temperature heating table is 180℃, the infrared measurement surface temperature is 128-168℃, and the internal glue temperature is estimated to be 158-165℃, which is consistent with the thermocouple measurement value), the error in the internal glue temperature estimation is ensured to be controlled within ±3℃, thus meeting the curing temperature control requirements.

[0039] This invention, through the above steps, enables accurate measurement of adhesive temperature without damaging the board or adhesive, ensuring both measurement accuracy and production continuity. The measured first temperature, representing the board surface temperature, and the calculated second temperature, representing the adhesive's internal temperature, form a multi-layered temperature sensing system. This system effectively identifies "false compliance" phenomena where the surface temperature meets the standard but the internal adhesive temperature fails to meet it, significantly improving the monitoring accuracy of adhesive curing quality.

[0040] S4. Calculate the temperature difference between the first temperature of the board surface and the second temperature inside the adhesive. Compare the first temperature, the second temperature, and the temperature difference with their respective preset thresholds, and determine whether there is a temperature anomaly based on the comparison results. This includes the following sub-steps: S41. Obtain the first preset threshold from the preset thresholds. The first preset threshold is an allowable range set for the surface temperature of the board, used to measure whether the surface temperature of the board is in a normal state. Since the surface temperature of the board is affected by heat dissipation from the environment, it will be lower than the internal temperature of the glue during the heating process. Its fluctuation can reflect the uniformity of heating and the degree of interference from environmental factors.

[0041] The first temperature of the surface of multiple adhesive-coated areas of the board is obtained. Subtracting each pair of first temperatures yields multiple fluctuation values ​​that characterize the average temperature level of the board. These fluctuation values ​​are then compared with a first preset threshold to obtain a first comparison result. In this embodiment, the first preset threshold is preferably ±2℃.

[0042] The first comparison result is as follows: the fluctuation value of the first temperature on the surface of the glued area of ​​the board is within ±2℃ or not within ±2℃. If the fluctuation range of the first temperature is within ±2℃, it indicates that the surface of the board is heated evenly; conversely, if the fluctuation range of the first temperature is not within ±2℃, it indicates that the surface of the board is heated unevenly.

[0043] S42. Obtain the second preset threshold from the preset thresholds. The second preset threshold is an allowable range set for the internal temperature of the adhesive, used to measure whether the actual internal temperature of the adhesive has reached the ideal curing temperature conditions. Since the cross-linking and curing reaction of the adhesive needs to be carried out within a specific temperature window, too low a temperature will lead to insufficient curing and insufficient bonding strength; too high a temperature may lead to over-curing, embrittlement or decomposition of the adhesive layer, which will also affect the coating quality.

[0044] The second temperature is compared with a second preset threshold to obtain a second comparison result. In this embodiment, the second preset threshold is preferably 158-165℃. The second comparison result includes the following information: whether the second temperature is between 158-165℃. If the second temperature is below 158℃, it indicates that the internal temperature of the adhesive has not reached the ideal curing temperature, and the adhesive may not cure sufficiently; if the second temperature is above 165℃, it indicates that the internal temperature of the adhesive is too high, which may lead to over-curing; if the second temperature is between 158-165℃, it indicates that the internal temperature of the adhesive meets the curing requirements.

[0045] S43. Calculate the temperature difference between the first and second temperatures. The temperature difference reflects the temperature loss caused by the thermal resistance of the board during the heat transfer from the surface of the board to the interior of the adhesive. Under normal heating conditions, since the surface of the board is directly exposed to the environment, heat is continuously lost to the surrounding air, while the heat loss inside the adhesive is relatively small. Therefore, the temperature inside the adhesive is usually higher than the surface temperature of the board, and there is a certain positive temperature difference between the two.

[0046] A preset temperature difference threshold is obtained from the preset threshold, and the calculated temperature difference is compared with the preset temperature difference threshold to obtain a third comparison result. In this embodiment, the preset temperature difference threshold is preferably 30℃ (this value comes from experimental data). The above third comparison result includes the following information: whether the temperature difference is 30℃. If the temperature difference exceeds 30℃, it indicates that the temperature difference between the board surface and the inside of the adhesive is too large, which may indicate uneven heating, abnormal board thickness, or abnormal heat conduction; if the temperature difference is less than or equal to 30℃, it indicates that the heat transfer from the board surface to the inside of the adhesive is normal, and the temperature of the board surface can effectively represent the curing temperature inside the adhesive.

[0047] S44. Based on the first comparison result, the second comparison result, and the third comparison result, a comprehensive determination is made as to whether a temperature anomaly exists. The determination logic is as follows: if any one of the first, second, and third comparison results exceeds the corresponding preset threshold range, a temperature anomaly is determined to exist. Specifically: if the fluctuation value exceeds ±2℃, it indicates that the surface temperature of the board is abnormal, and a temperature anomaly is directly determined to exist; if the second temperature exceeds 158-165℃, it indicates that the internal curing temperature of the adhesive is abnormal, and a temperature anomaly is directly determined to exist; if the temperature difference exceeds 30℃, it indicates that the heat conduction relationship between the surface of the board and the interior of the adhesive is abnormal, and a temperature anomaly is directly determined to exist; only when the first temperature, the second temperature, and the temperature difference are all within their respective preset threshold ranges is a temperature anomaly determined to exist.

[0048] S5. Receive the judgment result output from step S4. If an abnormal temperature is found, adjust the heating parameters; otherwise, maintain the current heating parameters and return to step S1 until curing is complete. The specific process is as follows: When the determination result indicates that there is no temperature anomaly, it means that the current surface temperature of the board, the internal temperature of the adhesive, and the temperature difference between the two are all within their respective preset normal ranges, and the adhesive is curing according to the expected curing temperature conditions. In this case, the current heating parameters are maintained unchanged, that is, the current operating frequency and heating time of the high-frequency electromagnetic coil are kept constant, and the heating conditions are not adjusted. Then, the process returns to step S1 to continue heating the board, so that the temperature monitoring and control cycle continues.

[0049] When the determination result indicates a temperature anomaly, it means that the current temperature state has deviated from the normal process window, and intervention measures are required. At this time, the following three parallel actions are executed: ① Adjust the current heating parameters: Based on the anomaly type information provided by the three comparison results in S4, make targeted adjustments to the heating parameters. For example, if the second temperature is below 158℃, it indicates that the internal temperature of the adhesive is insufficient. In this case, increase the operating frequency of the high-frequency electromagnetic coil or extend the heating time to increase heat input. If the fluctuation value of the first temperature is higher than 2℃ while the second temperature is normal, it indicates that the surface of the board is overheated but the internal temperature is acceptable. In this case, the heating power may be reduced or the coil position adjusted to improve heat distribution. If the temperature difference exceeds 30℃, it indicates abnormal heat conduction, and it may be necessary to check the board thickness or material consistency. After adjusting the heating parameters, return to and re-execute step S1.

[0050] ② Trigger abnormal alarm: Send an alarm command to the alarm unit to trigger an audible and visual alarm, and display the abnormal location and type on the control panel to remind on-site personnel to pay attention and handle the situation in a timely manner.

[0051] ③ Trigger anomaly timing: Start an anomaly timing mechanism to record the duration of the temperature anomaly. The anomaly timing mechanism is designed to prevent control oscillations caused by frequent switching between abnormal and normal states, and also provides a time-based basis for automatic safety protection.

[0052] Upon triggering the abnormal timing, the process returns to step S1. After heating continues in step S1, steps S2, S3, and S4 will re-acquire temperature data and perform abnormality assessment. When the assessment result indicates that the temperature abnormality has been eliminated, meaning that step S4's comprehensive assessment shows no further temperature abnormalities, it indicates that the adjusted heating parameters have taken effect and the temperature has returned to normal. At this point, the abnormal timing is cleared, the timer is reset to zero, and step S1 continues, maintaining the current heating parameters for normal heating. If the assessment result still indicates a temperature abnormality, and the abnormality persists even after multiple adjustments, until the abnormal timing shows the temperature abnormality lasting for more than 5 seconds without being eliminated, it indicates that adjusting the heating parameters cannot restore the temperature to the normal range within a reasonable time. This may indicate equipment malfunction, abnormal board material, or other systemic problems that cannot be resolved by parameter adjustment. In this case, heating automatically stops to prevent continuous heating in an abnormal state from causing a batch of defective products or equipment damage, while retaining the alarm status for personnel to troubleshoot.

[0053] This invention uses temperature anomalies as the basis for adjusting heating parameters, forming a complete closed-loop control process of "temperature measurement → calculation → judgment → adjustment". This process can effectively suppress the interference of factors such as ambient temperature and differences in board material on the curing temperature, so that the curing temperature of the adhesive remains stable within the ideal range, avoiding insufficient or excessive curing, thereby ensuring the sealing and bonding strength of the adhesive.

[0054] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for controlling adhesive curing based on anomaly detection, characterized in that, include: S1. Heat the sheet metal to raise its temperature; S2. The surface temperature of the board is collected using a non-contact temperature measurement method to obtain the first temperature; S3. Based on the first temperature and the thermal conductivity characteristics of the board and the adhesive, calculate the internal temperature of the adhesive to obtain the second temperature; S4. Calculate the temperature difference between the first temperature and the second temperature, calculate the fluctuation value of the first temperature, compare the fluctuation value, the second temperature, and the temperature difference with the corresponding preset thresholds, and determine whether there is a temperature abnormality based on the comparison results. S5. Based on the judgment result, select whether to adjust the heating parameters, and then return to step S1 until curing is complete.

2. The adhesive curing control method based on anomaly detection according to claim 1, characterized in that, In S1, a high-frequency electromagnetic coil is used to heat the plate.

3. The adhesive curing control method based on anomaly detection according to claim 2, characterized in that, Specifically, S1 involves: supplying power to a high-frequency electromagnetic coil; the high-frequency electromagnetic coil converting electrical energy into an alternating electromagnetic field; the alternating electromagnetic field acting on the plate to generate eddy currents inside the plate; and the eddy currents causing the plate to heat up.

4. The adhesive curing control method based on anomaly detection according to claim 2, characterized in that, S1 further includes: obtaining the material of the board and the type of adhesive, setting the initial value of the heating parameter according to the material of the board and the type of adhesive, and the high-frequency electromagnetic coil heating the board according to the initial value.

5. The adhesive curing control method based on anomaly detection according to claim 1, characterized in that, S2 specifically involves: activating the infrared temperature sensor and aligning it with the adhesive coating area of ​​the board; the infrared temperature sensor receiving infrared radiation emitted from the surface of the adhesive coating area of ​​the board; the infrared temperature sensor generating a temperature signal based on the infrared radiation; and outputting the first temperature based on the temperature signal.

6. The adhesive curing control method based on anomaly detection according to claim 1, characterized in that, S3 specifically involves: obtaining the thermal diffusivity, specific heat capacity, and density of the board at a first temperature, calculating the thermal conductivity of the board; obtaining the thickness of the board; and, based on the first temperature, the thermal conductivity of the board, and the thickness of the board, calculating the internal temperature of the adhesive using a heat conduction model to obtain the second temperature.

7. The adhesive curing control method based on anomaly detection according to claim 6, characterized in that, The method of calculating the temperature inside the adhesive based on the heat conduction model to obtain the second temperature specifically involves: obtaining the temperature gradient of the adhesive-coated area of ​​the board, calculating the heat flux density of the adhesive-coated area of ​​the board based on the thermal conductivity of the board and the temperature gradient, and calculating the temperature inside the adhesive based on the first temperature, the heat flux density, the thickness of the board and the thermal conductivity of the board to obtain the second temperature.

8. The adhesive curing control method based on anomaly detection according to claim 1, characterized in that, S4 specifically involves: acquiring multiple first temperatures, calculating the difference between every two first temperatures as a fluctuation value, comparing the fluctuation value with a first preset threshold in the preset threshold, and obtaining a first comparison result; The second temperature is compared with the second preset threshold in the preset threshold to obtain a second comparison result; Calculate the temperature difference between the first temperature and the second temperature, compare the temperature difference with a preset temperature difference threshold in the preset threshold, and obtain a third comparison result; Based on the first comparison result, the second comparison result, and the third comparison result, it is determined whether there is a temperature anomaly.

9. The adhesive curing control method based on anomaly detection according to claim 1, characterized in that, S5 specifically involves: obtaining a determination result; if the determination result indicates that there is no temperature abnormality, maintaining the current heating parameters and returning to step S1; if the determination result indicates that there is a temperature abnormality, adjusting the current heating parameters, returning to step S1, and triggering an abnormal alarm and an abnormal timer; if the temperature abnormality has been eliminated after returning to step S1, clearing the abnormal timer and continuing to execute step S1; if the temperature abnormality has not been eliminated when the abnormal timer reaches a preset duration, automatically stopping heating.

10. A coating curing control system based on anomaly detection, employing the coating curing control method as described in any one of claims 1-9, characterized in that, include: The system includes a heating module, a temperature measuring module, a data processing module, a control module, and an alarm module. The heating module is used to perform high-frequency electromagnetic heating on the board to raise its temperature. The temperature measuring module is used to collect a first temperature on the surface of the board using a non-contact temperature measurement method. The data processing module is used to calculate the internal temperature of the adhesive based on the first temperature and the thermal conductivity characteristics of the board and the adhesive, obtain a second temperature, calculate the temperature difference between the first temperature and the second temperature, compare the first temperature, the second temperature, and the temperature difference with corresponding preset thresholds, and determine whether there is a temperature anomaly based on the comparison results. The control module receives the judgment result from the data processing module. If an abnormal temperature is detected, it sends an instruction to the heating module to adjust the heating parameters; otherwise, it sends an instruction to the heating module to maintain the current heating parameters and an alarm instruction to the alarm module. The alarm module receives the alarm instruction from the control module and performs an audible and visual alarm.

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