PCB cooling control method and system based on real-time temperature sensing

Abstract

The invention relates to the technical field of PCB cooling, and discloses a PCB cooling control method and system based on real-time temperature sensing, and the method comprises the steps: obtaining the temperature monitoring data and position information of a plurality of PCBs; determining a temperature abnormal area, and analyzing the temperature change trend of continuous time points; based on the temperature abnormal area and the temperature change trend, identifying an overheat area, marking the space coordinates of the overheat area, and determining the temperature change rate of the overheat area; generating temperature evaluation data; according to the space coordinates and the temperature evaluation data, the cooling demand strength value of each cooling area is determined, and a cooling control instruction is generated; and outlet temperature data of the PCB at the outlet are obtained, and when the outlet temperature data exceed a safe temperature threshold value, the operation parameters of the cooling areas are corrected. The cooling uniformity is improved, and the risks of plate warping and welding spot damage caused by thermal stress are reduced.

Description

Technical Field

[0001] This invention relates to the field of PCB cooling technology, and more specifically, to a PCB cooling control method and system based on real-time temperature sensing. Background Technology

[0002] In the manufacturing process of printed circuit boards (PCBs), rapid and uniform cooling is required after high-temperature processes such as reflow soldering and wave soldering. This step is crucial for ensuring soldering quality and suppressing board warping, solder joint cracking, and thermal damage to components caused by thermal stress, directly affecting product yield and long-term reliability. As electronic products develop towards high density, miniaturization, and multifunctionality, the layout of components on PCBs is becoming increasingly complex, highlighting the problem of uneven heat load distribution, and placing higher demands on the precision and adaptability of the cooling process.

[0003] Currently, most mainstream cooling control solutions in the industry employ forced air cooling or liquid cooling systems with fixed parameters. For example, constant-speed fan arrays or fixed-flow cooling nozzles are configured at the cooling station, and global control is performed based on preset time or overall average temperature. Some solutions introduce infrared thermal imagers or distributed temperature sensors for monitoring, combined with simple threshold triggers to adjust cooling intensity. However, existing cooling control technologies have significant shortcomings: weak spatial perception, making it difficult to accurately locate local hotspots and temperature gradients; passive response mechanisms, lacking prediction of temperature change trends; failure to dynamically match cooling actions with PCB movement speed and position, leading to spatiotemporal mismatch; feedback correction relying on simple algorithms, easily causing overshoot or oscillation; and insufficient synchronization accuracy of temperature and position data, affecting control reliability and cooling uniformity.

[0004] Therefore, it is necessary to design a PCB board cooling control method and system based on real-time temperature sensing to solve the problems existing in the current technology. Summary of the Invention

[0005] In view of this, the present invention proposes a PCB board cooling control method and system based on real-time temperature sensing, aiming to solve the problems of poor reliability and low cooling uniformity of PCB cooling control.

[0006] In one aspect, the present invention proposes a PCB board cooling control method based on real-time temperature sensing, comprising:

[0007] Acquire temperature monitoring data and location information for several PCB boards;

[0008] Based on the temperature monitoring data, the spatial gradient of the temperature field is calculated to determine the temperature anomaly region; the temperature change trend at continuous time points is analyzed; based on the temperature anomaly region and the temperature change trend, the overheated region is identified, the spatial coordinates of the overheated region are marked, and the temperature change rate of the overheated region is determined; based on the area ratio of the overheated region and the temperature change rate, temperature assessment data is generated.

[0009] Based on the spatial coordinates and temperature assessment data, the cooling demand intensity value of each cooling zone is determined; based on the cooling demand intensity value, the operating parameters of each cooling zone are adjusted, and cooling control commands are generated.

[0010] The outlet temperature data of the PCB board at the outlet is obtained. When the outlet temperature data exceeds the safe temperature threshold, the temperature deviation value is determined based on historical cooling effect data and the PCB board moving speed. The operating parameters of each cooling zone are then corrected based on the temperature deviation value.

[0011] Furthermore, identifying overheated regions, marking the spatial coordinates of the overheated regions, and determining the rate of temperature change of the overheated regions include:

[0012] When the temperature value of the abnormal temperature area exceeds the high temperature threshold and the slope of the temperature change trend is greater than the rate of increase threshold, the current area is determined to be an overheated area.

[0013] Based on the coordinate system of the PCB board, the boundary point positions of the overheated area are obtained, and the vertex coordinates of the minimum bounding rectangle are determined as the spatial coordinates.

[0014] The rate of temperature change is determined based on the temperature time series of the overheated region.

[0015] Furthermore, when generating temperature assessment data, the following are included:

[0016] Based on the physical dimensions of the PCB board and the spatial coordinates, the area of ​​the overheated region is determined, and the area percentage is determined.

[0017] Based on the area ratio, the range level of the overheated area is determined; based on the temperature change rate, the rate level of temperature rise is determined; and based on the range level and rate level, the temperature assessment data is generated.

[0018] Furthermore, when determining the cooling demand intensity value for each cooling zone, the following is included:

[0019] Based on the spatial coordinates, the overheated area is mapped to each cooling area; the basic cooling intensity is determined according to the risk level in the temperature assessment data; the cooling response time is determined in combination with the PCB board's moving speed; and the cooling demand intensity value of each cooling area is determined according to the basic cooling intensity and the cooling response time.

[0020] Furthermore, determining the temperature deviation value includes:

[0021] Obtain the expected outlet temperature under the same operating conditions from the historical cooling effect data; compare the expected outlet temperature with the actual outlet temperature to determine the basic temperature deviation; determine the temperature adjustment advance based on the PCB board's moving speed and the length of the cooling area; determine the temperature deviation value based on the basic temperature deviation and the temperature adjustment advance.

[0022] Furthermore, when correcting the operating parameters of each cooling zone based on the temperature deviation value, the following steps are included:

[0023] The temperature deviation value is proportionally allocated to each cooling zone; the parameter adjustment amount is determined according to the proportion allocated to each cooling zone; based on the parameter adjustment amount, the fan speed, coolant flow rate and air duct guide angle of each cooling zone are corrected.

[0024] Furthermore, when acquiring temperature monitoring data and location information for several PCB boards, this includes:

[0025] Temperature monitoring data on the surface of the PCB board is collected by an array of temperature sensors installed along the conveyor belt.

[0026] The position information of the PCB board during its movement is obtained by a position encoder installed along the conveyor belt.

[0027] Furthermore, when acquiring temperature monitoring data and location information for several PCB boards, the process also includes:

[0028] The temperature monitoring data and location information are synchronized in time.

[0029] Furthermore, when identifying areas of temperature anomalies, the following should be considered:

[0030] Based on the spatial distribution of the temperature sensor array, a temperature distribution matrix is ​​constructed on the surface of the PCB board; the spatial rate of temperature change is determined according to the temperature difference between adjacent points in the temperature distribution matrix; the temperature gradient vector and its magnitude are determined according to the spatial rate of temperature change; the magnitude of the temperature gradient vector is compared with a gradient threshold; when the magnitude of the temperature gradient vector exceeds the gradient threshold, the current region is determined to be a temperature anomaly region.

[0031] Compared with existing technologies, the advantages of this invention are as follows: By combining temperature field spatial gradient calculation with temperature change trend analysis, the spatial coordinates, range, and heating rate of overheated areas are identified, enabling dynamic allocation of cooling resources on demand. This avoids local overheating or excessive cooling in low-temperature areas, improves cooling uniformity, and reduces the risk of board warping and solder joint damage caused by thermal stress. Incorporating the temperature change rate into the evaluation system and generating multi-dimensional temperature evaluation data based on area proportions enables the control system to predict trends and proactively adjust cooling intensity before abnormal temperature deterioration, shortening response delay and adapting to high-speed production lines and sudden changes in heat load. Deeply integrating the spatial coordinates of overheated areas with the real-time movement speed of the PCB board, the cooling demand intensity and response time of each cooling area are dynamically calculated, ensuring precise spatial and temporal alignment between cooling actions and the moving target area. Based on the outlet temperature deviation, historical cooling effects, movement speed, and cooling path length are integrated to calculate adjustment lead time, achieving precise and adaptive parameter correction, suppressing overshoot and oscillations prone to occur in traditional control, and improving long-term operational stability and robustness.

[0032] On the other hand, this application also provides a PCB board cooling control system based on real-time temperature sensing, for applying the above-mentioned PCB board cooling control method based on real-time temperature sensing, including:

[0033] The data acquisition unit is configured to acquire temperature monitoring data and location information of several PCB boards.

[0034] Anomaly assessment unit is configured to perform temperature field spatial gradient calculation based on the temperature monitoring data to determine temperature anomaly regions; analyze temperature change trends at continuous time points; identify overheated regions based on the temperature anomaly regions and temperature change trends, mark the spatial coordinates of the overheated regions, and determine the temperature change rate of the overheated regions; and generate temperature assessment data based on the area ratio of the overheated regions and the temperature change rate.

[0035] The command control unit is configured to determine the cooling demand intensity value of each cooling zone based on the spatial coordinates and temperature assessment data; and to adjust the operating parameters of each cooling zone based on the cooling demand intensity value, thereby generating a cooling control command.

[0036] The operation correction unit is configured to acquire the outlet temperature data of the PCB board at the outlet. When the outlet temperature data exceeds the safe temperature threshold, the temperature deviation value is determined based on historical cooling effect data and the PCB board moving speed, and the operating parameters of each cooling zone are corrected based on the temperature deviation value.

[0037] It is understandable that the above-mentioned PCB board cooling control methods and systems based on real-time temperature sensing have the same beneficial effects, and will not be elaborated further here. Attached Figure Description

[0038] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0039] Figure 1 A flowchart of a PCB board cooling control method based on real-time temperature sensing provided in an embodiment of the present invention;

[0040] Figure 2 This is a functional block diagram of a PCB cooling control system based on real-time temperature sensing, provided in an embodiment of the present invention. Detailed Implementation

[0041] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the disclosure to those skilled in the art. It should be noted that, unless otherwise specified, embodiments and features in the embodiments of the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0042] In some embodiments of this application, see Figure 1 As shown, a PCB board cooling control method based on real-time temperature sensing is proposed, including:

[0043] S100: Acquires temperature monitoring data and location information for several PCB boards;

[0044] S200: Based on temperature monitoring data, calculate the spatial gradient of the temperature field to identify temperature anomaly areas; analyze the temperature change trend at continuous time points; based on the temperature anomaly areas and temperature change trends, identify overheated areas, mark the spatial coordinates of the overheated areas, and determine the temperature change rate of the overheated areas; generate temperature assessment data based on the area ratio and temperature change rate of the overheated areas.

[0045] S300: Based on spatial coordinates and temperature assessment data, determine the cooling demand intensity value of each cooling zone; based on the cooling demand intensity value, adjust the operating parameters of each cooling zone and generate cooling control commands;

[0046] S400: Obtain the outlet temperature data of the PCB board at the outlet. When the outlet temperature data exceeds the safe temperature threshold, determine the temperature deviation value based on historical cooling effect data and PCB board moving speed, and correct the operating parameters of each cooling zone based on the temperature deviation value.

[0047] Specifically, step S100: Acquire temperature monitoring data and position information. Above the cooling station on the PCB board conveyor line, a temperature sensor array is evenly arranged along the conveying direction. This array consists of multiple high-precision infrared temperature sensors used to scan the surface temperature of the passing PCB boards in real time and generate temperature monitoring data. Simultaneously, a high-resolution position encoder is installed on the conveyor belt drive shaft to detect the position coordinates of the PCB boards during the conveying process in real time. To ensure spatiotemporal consistency of the data, the temperature monitoring data and position information are timestamped and synchronized, and the temperature data and position coordinates collected at the same time are associated and stored.

[0048] Step S200: Temperature Anomaly Identification and Assessment. Based on the synchronized temperature data, a two-dimensional temperature distribution matrix is ​​constructed using the PCB board geometry as a reference. The temperature difference between adjacent grid points in the matrix is ​​calculated to obtain the spatial rate of temperature change, and the temperature gradient vector and its magnitude are further calculated. When the magnitude of the gradient vector exceeds a preset gradient threshold (e.g., 3℃ / mm), the region is determined to be a temperature anomaly region. Simultaneously, time-series analysis is performed on temperature data from multiple consecutive sampling periods to fit a temperature change curve, and its slope is calculated as the temperature change trend. If the measured temperature of the temperature anomaly region exceeds the high temperature threshold (e.g., 85℃) and the slope of the temperature change trend is greater than the rate of increase threshold (e.g., 2℃ / s), the region is confirmed as an overheated region. Subsequently, based on the PCB board coordinate system, the boundary contour points of the overheated region are extracted, and the coordinates of the four vertices of its minimum bounding rectangle are calculated as spatial coordinates. Based on the temperature values ​​of the region at consecutive time points, the temperature change rate is calculated through linear regression. Furthermore, the area ratio is calculated by combining the total area of ​​the PCB board and the area of ​​the overheated area. Based on the preset classification standards (e.g., area ratio <5% is low risk, 5%-15% is medium risk, >15% is high risk; temperature change rate <1℃ / s is slow, 1-3℃ / s is medium speed, >3℃ / s is fast), the area ratio is mapped to a range level, and the temperature change rate is mapped to a speed level, thus generating comprehensive temperature assessment data that includes risk levels.

[0049] Step S300: Cooling Demand Calculation and Command Generation. Map the spatial coordinates of the marked overheated areas to multiple preset cooling zones (e.g., three cooling zones divided along the conveying direction: front, middle, and rear). Based on the risk level in the temperature assessment data (e.g., high risk corresponds to a basic cooling intensity value of 80%), determine the basic cooling intensity for each cooling zone. Simultaneously, combining the current PCB board movement speed (calculated in real-time by the position encoder) and the length of the cooling zone, calculate the cooling response time (i.e., the time required for the PCB board to move from its current position to the target cooling zone). Dynamically weight the basic cooling intensity based on the response time to obtain the cooling demand intensity value for each cooling zone. Based on this intensity value, generate cooling control commands to adjust the fan speed (e.g., 0-3000 rpm), coolant flow rate (e.g., 0-10 L / min), and air duct guide angle (e.g., 0°-30°) for the corresponding cooling zone.

[0050] Step S400: Outlet Feedback Correction. A temperature detection point is set at the cooling station outlet to collect real-time outlet temperature data of the PCB board. When the outlet temperature exceeds a preset safe temperature threshold (e.g., 45℃), the expected outlet temperature record under the same operating conditions (including the same PCB type, moving speed, initial temperature, etc.) is retrieved from the historical database. The difference between the actual outlet temperature and the expected value is calculated to obtain the basic temperature deviation. Simultaneously, based on the current PCB board moving speed and the total length of the cooling area, the required advance amount for temperature adjustment (i.e., how far in advance the cooling parameters need to be adjusted) is calculated. The basic temperature deviation and the advance amount are weighted and integrated to determine the comprehensive temperature deviation value. Subsequently, according to the influence weight of each cooling area on the outlet temperature (e.g., 30% for the front area, 50% for the middle area, and 20% for the rear area), the temperature deviation value is allocated to each area, generating parameter adjustment amounts (e.g., the increase in rotational speed is the product of the ratio and the temperature deviation value). The operating parameters of each cooling area are corrected in real-time to achieve closed-loop optimization control.

[0051] Understandably, by combining the calculation of the spatial gradient of the temperature field with the analysis of continuous temperature change trends, the location, range, and heating rate of overheated areas are identified, enabling on-demand and targeted allocation of cooling resources, improving cooling uniformity, and suppressing board warping and solder joint damage caused by thermal stress. Deep integration of the real-time position and movement speed of the PCB board dynamically matches the spatiotemporal relationship between cooling actions and target areas, avoiding cooling lag or misalignment and improving cooling efficiency. An adaptive closed-loop correction mechanism based on outlet temperature deviation, historical cooling effects, and process parameters is introduced to calculate and adjust the lead time, suppressing overshoot and oscillation in parameter adjustments and enhancing stability and robustness under different operating conditions.

[0052] In some embodiments of this application, identifying overheated regions, marking the spatial coordinates of the overheated regions, and determining the temperature change rate of the overheated regions include:

[0053] When the temperature value in an abnormal temperature area exceeds the high temperature threshold and the slope of the temperature change trend is greater than the rate of increase threshold, the current area is determined to be an overheated area.

[0054] Based on the coordinate system of the PCB board, the boundary point positions of the overheated area are obtained, and the vertex coordinates of the minimum bounding rectangle are determined as spatial coordinates.

[0055] The rate of temperature change is determined based on the temperature time series of the overheated region.

[0056] Specifically, in the implementation of identifying overheated areas, the real-time temperature data within the abnormal temperature area is first subjected to a dual judgment: when the highest temperature value of the area continuously exceeds a preset high-temperature threshold (e.g., 85℃, which can be set according to PCB material and process requirements), and the linear slope fitted based on temperature data from five consecutive sampling periods is greater than the rate of rise threshold (e.g., 1.8℃ / s), the area is confirmed as an overheated area. For spatial coordinate marking, a two-dimensional coordinate system is established with the lower left corner of the PCB board as the origin. The coordinates of all boundary temperature measurement points in the overheated area are extracted, and the minimum bounding rectangle is calculated using the convex hull algorithm. The coordinates of its four vertices (e.g., (x1, y1), (x2, y2), etc.) are recorded as spatial coordinate identifiers. The rate of temperature change is determined by performing a sliding window linear regression analysis on the temperature time series of all temperature measurement points within the overheated area. The average slope of the area is taken as the dynamic heating rate of the overheated area, ensuring that the parameters reflect the true thermal evolution trend.

[0057] Understandably, the overheating area identification and quantification method avoids misjudgment caused by instantaneous interference by using the dual criteria of "temperature threshold + trend of change"; it uses the coordinates of the vertices of the minimum bounding rectangle as spatial markers, which simplifies data expression and provides a geometric basis for accurate mapping of cooling areas; and it provides key time-series parameters for generating cooling demand intensity by combining the temperature rise rate dynamically calculated from the temperature time series.

[0058] In some embodiments of this application, generating temperature assessment data includes:

[0059] Based on the physical dimensions and spatial coordinates of the PCB board, determine the area of ​​the overheated region and its proportion.

[0060] Based on the area proportion, the range level of the overheated area is determined; based on the temperature change rate, the rate level of temperature rise is determined; and temperature assessment data is generated based on the range level and the rate level.

[0061] Specifically, in the process of generating temperature assessment data, firstly, based on the pre-stored physical dimensions of the PCB board (e.g., length × width = 300mm × 200mm) and the coordinates of the vertices of the minimum bounding rectangle of the overheated area, the actual area of ​​the overheated area is calculated using a coordinate geometry algorithm, and its percentage of the total PCB board area is obtained (area percentage). Then, the area percentage is compared with preset grading thresholds: an area percentage < 5% is classified as "low range level," 5% < area percentage < 15% as "medium range level," and an area percentage > 15% as "high range level." Simultaneously, the temperature change rate (unit: ℃ / s) is compared with a rate threshold: a temperature change rate < 1.0℃ / s is "low speed level," 1.0℃ / s < temperature change rate < 2.5℃ / s is "medium speed level," and a temperature change rate > 2.5℃ / s is "high speed level." Finally, based on the preset two-dimensional assessment matrix (e.g., high range + high speed → "emergency risk", medium range + medium speed → "medium risk"), structured temperature assessment data containing risk level identifiers, quantitative scores and priority labels are generated and directly output to the cooling demand calculation.

[0062] Understandably, the assessment mechanism transforms the geometric characteristics and dynamic thermal behavior of the overheated area into standardized and quantified risk indicators, improving the objectivity of the assessment and the efficiency of decision-making; the two-dimensional hierarchical processing avoids misjudgment based on a single parameter and enhances the robustness of identification for different thermal anomaly scenarios; and the structured output data provides a clear input basis for calculating cooling demand intensity.

[0063] In some embodiments of this application, determining the cooling demand intensity value for each cooling zone includes:

[0064] Based on spatial coordinates, the overheated area is mapped to each cooling area; the basic cooling intensity is determined according to the risk level in the temperature assessment data; the cooling response time is determined in combination with the PCB board's moving speed; and the cooling demand intensity value of each cooling area is determined based on the basic cooling intensity and the cooling response time.

[0065] Specifically, when determining the cooling demand intensity value for each cooling zone, the spatial coordinates of the minimum bounding rectangle of the overheated zone are first spatially matched with the pre-set cooling zone layout of the production line to identify cooling zones that overlap with the overheated zone. Influence weights are then assigned based on the proportion of the overlapping area to the total area of ​​the overheated zone. Subsequently, based on the risk level (e.g., "urgent," "high," "medium," "low") identified in the temperature assessment data, the corresponding basic cooling intensity level (e.g., "urgent" risk corresponds to a high intensity level) is retrieved from the process parameter library. Simultaneously, the real-time PCB board movement speed is combined to assess the time window required for the board to pass through the target cooling zone: the faster the movement speed, the shorter the allowable cooling time, indicating a need to increase the urgency of the response. Finally, the basic cooling intensity level and the urgency of the cooling response time are dynamically integrated—when the response time window is short, the cooling demand intensity is moderately increased based on the basic intensity level; when the window is ample, the basic intensity is maintained or fine-tuned, and distributed to each associated cooling zone according to the spatial overlap weight, generating the final cooling demand intensity value sequence.

[0066] Understandably, by converting movement speed into response urgency and incorporating it into intensity decision-making, the problem of cooling lag or redundancy caused by speed changes in traditional control is overcome; the spatial weight allocation mechanism avoids the dispersion and waste of cooling resources, and improves the targeting and energy efficiency of regulation.

[0067] In some embodiments of this application, determining the temperature deviation value includes:

[0068] Obtain the expected outlet temperature under the same operating conditions from historical cooling effect data; compare the expected outlet temperature with the actual outlet temperature to determine the basic temperature deviation; determine the temperature adjustment lead based on the PCB board's moving speed and the length of the cooling zone; determine the temperature deviation value based on the basic temperature deviation and the temperature adjustment lead.

[0069] Specifically, in determining the temperature deviation value, the process begins by retrieving records from the historical cooling effect database that closely match the current operating conditions (matching conditions include PCB board model, thickness, component layout characteristics, inlet temperature, and basic setting parameters of the current cooling area). The expected outlet temperature under the corresponding operating conditions is then extracted as a benchmark reference value. The actual outlet temperature of the PCB board at the outlet, monitored in real time, is compared with this expected value to obtain the basic temperature deviation reflecting the degree of deviation in the current cooling effect. Simultaneously, considering the current real-time moving speed of the PCB board and the physical length of the cooling area, the process response time required from issuing a parameter adjustment command to the cooling effect appearing at the outlet is dynamically assessed. Based on this, the temperature adjustment lead time is determined—the faster the moving speed or the shorter the cooling area, the greater the required advance adjustment. Finally, the absolute value and sign of the basic temperature deviation, along with the urgency of the response represented by the temperature adjustment lead time, are comprehensively evaluated: when the basic deviation is large and the response window is short, the temperature deviation value is moderately increased to strengthen the correction; when the deviation is small or the response window is ample, a mild correction strategy is adopted to generate a final temperature deviation value that balances correction accuracy and timeliness.

[0070] Understandably, by accurately benchmarking the expected and measured values ​​under historical operating conditions, the evaluation interference caused by environmental fluctuations and individual differences is eliminated, making the deviation judgment more process-specific; the adjustment lead mechanism based on moving speed and cooling path transforms physical time delay into a controllable correction factor, improving the foresight and timeliness of feedback adjustment; the collaborative decision-making logic of basic deviation and lead avoids the problems of overshoot, oscillation or insufficient correction caused by response lag in traditional feedback control.

[0071] In some embodiments of this application, when correcting the operating parameters of each cooling zone based on the temperature deviation value, the following are included:

[0072] The temperature deviation value is proportionally allocated to each cooling zone; the parameter adjustment amount is determined according to the proportion allocated to each cooling zone; based on the parameter adjustment amount, the fan speed, coolant flow rate and air duct guide angle of each cooling zone are corrected.

[0073] Specifically, in the implementation of correcting the operating parameters of each cooling zone based on temperature deviation values, the temperature deviation values ​​are first allocated proportionally according to the spatial overlap weight between each cooling zone and the overheated zone (this weight has been determined during the cooling demand intensity calculation stage), so that the zone more closely associated with thermal anomalies bears the main responsibility for correction. Subsequently, for each cooling zone, the allocated proportion is converted into specific parameter adjustment amounts by combining it with a preset safety adjustment coefficient, and strictly limited to the adjustment range allowed by the equipment (e.g., the fan speed adjustment range does not exceed ±15% of the current value). On this basis, multi-dimensional corrections are executed collaboratively according to process priorities: first, the fan speed is adjusted to achieve rapid thermal response, then the coolant flow rate is fine-tuned to optimize the heat exchange depth, and finally, the air duct guide angle is calibrated to accurately guide airflow to cover the target area; all correction commands are sent to the execution unit via the controller in incremental adjustment signals, and parameter feedback values ​​are read back in real time for closed-loop verification to ensure that the correction process is stable, controllable, and meets the equipment safety boundaries.

[0074] Understandably, the deviation allocation strategy guided by spatial weights achieves targeted optimization of cooling resources, avoiding energy waste and disturbances caused by traditional global proportional adjustment; multi-parameter hierarchical collaborative correction balances response speed and adjustment accuracy, suppressing control defects such as overshoot and oscillation; incremental commands and safety boundary constraints effectively ensure the reliability of equipment operation, and have high-precision and high-stability adaptive correction capabilities when dealing with abnormal outlet temperatures.

[0075] In some embodiments of this application, obtaining temperature monitoring data and location information of several PCB boards includes:

[0076] Temperature monitoring data on the surface of the PCB board is collected by an array of temperature sensors installed along the conveyor belt.

[0077] The position information of the PCB board during its movement is obtained by a position encoder installed along the conveyor belt.

[0078] In some embodiments of this application, when acquiring temperature monitoring data and location information of several PCB boards, the method further includes:

[0079] Time synchronization processing is performed on temperature monitoring data and location information.

[0080] Specifically, a dense array of non-contact infrared temperature sensors is deployed along the key monitoring section of the PCB board conveying path (covering the upstream of the cooling station and the area under action). As multiple PCB boards continuously travel along the conveyor belt, the array captures the complete thermal distribution data of each board surface in real time at a fixed sampling frequency. Simultaneously, a high-precision rotary encoder is installed on the conveyor belt drive shaft, continuously outputting pulse signals, which are then converted by a signal processing unit into the real-time displacement coordinates of each PCB board in the conveying coordinate system. To further ensure data reliability, high-precision time synchronization processing is performed on both types of data streams: all sensors and encoders share the same hardware clock source, embedding a microsecond-level unified timestamp for each frame of temperature data and each sampling point, and dynamically correcting transmission delays and sampling phase differences through a time alignment algorithm, ultimately generating a spatiotemporal correlation dataset that strictly corresponds one-to-one with the complete thermal history and spatial trajectory of each PCB board.

[0081] Understandably, the data acquisition and synchronization mechanism eliminates the timing misalignment problem of multi-source sensor data through hardware-level clock unification and timestamp alignment technology, improves the accuracy and continuity of temperature field spatial reconstruction, and avoids overheating area positioning offset or misjudgment caused by data asynchrony; the non-contact measurement and continuous synchronization strategy take into account both the high-speed operation requirements of the production line and the continuous monitoring capability of multiple boards.

[0082] In some embodiments of this application, determining an abnormal temperature region includes:

[0083] Based on the spatial distribution of the temperature sensor array, a temperature distribution matrix is ​​constructed on the surface of the PCB board. The spatial rate of temperature change is determined according to the temperature difference between adjacent points in the temperature distribution matrix. The temperature gradient vector and its magnitude are determined according to the spatial rate of temperature change. The magnitude of the temperature gradient vector is compared with the gradient threshold. When the magnitude of the temperature gradient vector exceeds the gradient threshold, the current region is determined to be a temperature anomaly region.

[0084] Specifically, in the implementation of identifying temperature anomaly areas, firstly, based on the physical layout coordinates of the temperature sensor array along the conveyor belt, the real-time collected discrete temperature data is reconstructed into a two-dimensional temperature distribution matrix covering the PCB board surface using a bilinear interpolation algorithm. Each grid point in the matrix precisely corresponds to the temperature value at a specific physical location on the board surface. Subsequently, each grid point in the matrix is ​​traversed, and the absolute value of the temperature difference between it and its adjacent grid points (upper, lower, left, and right) is calculated as the temperature spatial change rate of that point in the horizontal and vertical directions. By combining the change rates in each direction, a temperature gradient intensity value (i.e., the magnitude of the temperature gradient vector) is generated, representing the degree of spatial abrupt change in the temperature field at that location. The gradient intensity value of each grid point is compared in real time with a preset gradient threshold (e.g., 2.8℃ / mm, which is calibrated through process experiments based on the thermal characteristics of the PCB substrate and the thermal distribution characteristics of typical components). When the gradient intensity values ​​of multiple consecutive adjacent grid points continuously exceed the threshold and form a connected region, the region is determined to be a temperature anomaly area, and its spatial boundary range is marked.

[0085] Understandably, by quantifying the spatial abrupt change characteristics of the temperature field to identify abnormal areas, the shortcomings of traditional methods that rely solely on absolute temperature thresholds and are easily affected by environmental fluctuations are overcome, thus improving the accuracy and anti-interference capability of thermal anomaly detection. The gradient intensity criterion can keenly capture local heat concentration phenomena (such as heat accumulation under BGA packages), avoiding misjudging areas with high overall temperature but uniform distribution as risk points, and enabling cooling resources to be precisely focused on areas where there is a real risk of thermal gradient.

[0086] Based on another preferred embodiment described above, see [link to preferred embodiment]. Figure 2 As shown, this embodiment provides a PCB board cooling control system based on real-time temperature sensing, used to apply the above-mentioned PCB board cooling control method based on real-time temperature sensing, including:

[0087] The data acquisition unit is configured to acquire temperature monitoring data and location information of several PCB boards.

[0088] The anomaly assessment unit is configured to perform temperature field spatial gradient calculation based on temperature monitoring data to identify temperature anomaly areas; analyze temperature change trends at continuous time points; identify overheated areas based on temperature anomaly areas and temperature change trends, mark the spatial coordinates of overheated areas, and determine the temperature change rate of overheated areas; and generate temperature assessment data based on the area ratio and temperature change rate of overheated areas.

[0089] The command control unit is configured to determine the cooling demand intensity value of each cooling zone based on spatial coordinates and temperature assessment data; and to adjust the operating parameters of each cooling zone based on the cooling demand intensity value, thereby generating cooling control commands.

[0090] The operation correction unit is configured to acquire the outlet temperature data of the PCB board at the outlet. When the outlet temperature data exceeds the safe temperature threshold, the temperature deviation value is determined based on historical cooling effect data and the PCB board moving speed. The operating parameters of each cooling zone are then corrected based on the temperature deviation value.

[0091] The following examples illustrate this in detail:

[0092] S1: In a continuous production line for a communication motherboard (300mm×200mm), the PCB board enters the cooling station at a speed of 500mm / s after reflow soldering. A 10×10 infrared temperature sensor array (covering a 400mm×300mm area) is deployed above the conveyor belt, and a high-precision encoder is installed on the spindle. All equipment is synchronized via a hardware clock to ensure that the temperature data and position information timestamps are aligned for each frame.

[0093] S2: When PCB No. 3 reaches the cooling zone entrance, its surface temperature distribution matrix is ​​constructed. Calculations show that the temperature gradient magnitude in the upper right corner (coordinates approximately 245–285 mm, 145–185 mm) reaches 3.1℃ / mm (exceeding the preset gradient threshold of 2.5℃ / mm), thus identifying it as a temperature anomaly area. The real-time temperature of this area is 86℃ (exceeding the high temperature threshold of 80℃), and the temperature slope at five consecutive sampling points reaches 2.1℃ / s (exceeding the rate of rise threshold of 1.5℃ / s), confirming it as an overheated area. The vertex coordinates of the minimum bounding rectangle generated from its boundary points are (245, 145), (285, 145), (285, 185), and (245, 185), and the heating rate is determined to be 2.1℃ / s from the temperature time series. The overheated area is calculated to be 1600 mm², accounting for 2.67% of the total board area (belonging to the "small range" level). Combined with the "medium-speed rise" level, "medium risk" temperature assessment data is generated.

[0094] S3: Map this area to a three-section cooling zone (A: 0–200mm, B: 200–400mm, C: 400–600mm), determining that the main problem is in zone B; based on "medium risk," set the base cooling intensity to medium level, and combined with a 500mm / s moving speed, calculate a response window of only 0.4 seconds, dynamically increasing the cooling demand intensity of zone B to high level. Then generate the following commands: increase the fan speed in zone B from 70% to 85%, increase the coolant flow rate by 15%, and fine-tune the airflow guide angle by 5° to focus on the overheat coordinates.

[0095] S4: The measured outlet temperature of this board is 62℃, slightly exceeding the safety threshold of 60℃. The expected outlet temperature of 55℃ for the same model board in the historical database under the same inlet temperature and speed is retrieved, resulting in a basic deviation of +7℃. Considering the moving speed and cooling zone length, it is determined that intervention is needed 100mm earlier, resulting in a comprehensive temperature deviation value of +8. The deviation is distributed according to spatial weights to zone B (80%) and zones A / C (10% each). The fan speed in zone B is further increased by 5% to 90%, and the flow rate is finely adjusted.

[0096] In summary, by combining spatial gradient calculation of the temperature field with analysis of temperature change trends, the spatial coordinates, range, and heating rate of overheated areas are identified. This enables dynamic allocation of cooling resources on demand, avoiding localized overheating or excessive cooling in low-temperature areas, improving cooling uniformity, and reducing the risk of board warping and solder joint damage caused by thermal stress. Incorporating the temperature change rate into the evaluation system and generating multi-dimensional temperature assessment data based on area proportions gives the control system trend prediction capabilities. This allows for proactive adjustment of cooling intensity before abnormal temperature deterioration, shortening response delay and adapting to high-speed production lines and sudden changes in heat load. Deeply integrating the spatial coordinates of overheated areas with the real-time movement speed of the PCB board, the cooling demand intensity and response time of each cooling area are dynamically calculated, ensuring precise spatiotemporal alignment between cooling actions and the moving target area. Based on the outlet temperature deviation, historical cooling effects, movement speed, and cooling path length are integrated to calculate adjustment lead time, achieving precise and adaptive parameter correction. This suppresses overshoot and oscillations common in traditional control systems, improving long-term stability and robustness.

[0097] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A PCB board cooling control method based on real-time temperature sensing, characterized in that, include: Acquire temperature monitoring data and location information for several PCB boards; Based on the temperature monitoring data, the spatial gradient of the temperature field is calculated to determine the temperature anomaly region; Analyze the temperature change trend at continuous time points; Based on the temperature anomaly areas and temperature change trends, overheated areas are identified, their spatial coordinates are marked, and their temperature change rate is determined. Temperature assessment data is generated based on the area ratio of the overheated areas and their temperature change rate. Based on the spatial coordinates and temperature assessment data, the cooling demand intensity value of each cooling zone is determined; based on the cooling demand intensity value, the operating parameters of each cooling zone are adjusted, and cooling control commands are generated. The outlet temperature data of the PCB board at the outlet is obtained. When the outlet temperature data exceeds the safe temperature threshold, the temperature deviation value is determined based on historical cooling effect data and the PCB board moving speed. The operating parameters of each cooling zone are then corrected based on the temperature deviation value.

2. The PCB board cooling control method based on real-time temperature sensing according to claim 1, characterized in that, When identifying overheated regions, marking the spatial coordinates of the overheated regions, and determining the rate of temperature change of the overheated regions, the process includes: When the temperature value of the abnormal temperature area exceeds the high temperature threshold and the slope of the temperature change trend is greater than the rate of increase threshold, the current area is determined to be an overheated area. Based on the coordinate system of the PCB board, the boundary point positions of the overheated area are obtained, and the vertex coordinates of the minimum bounding rectangle are determined as the spatial coordinates. The rate of temperature change is determined based on the temperature time series of the overheated region.

3. The PCB board cooling control method based on real-time temperature sensing according to claim 2, characterized in that, When generating temperature assessment data, the following are included: Based on the physical dimensions of the PCB board and the spatial coordinates, the area of ​​the overheated region is determined, and the area percentage is determined. Based on the area ratio, the range level of the overheated area is determined; based on the temperature change rate, the rate level of temperature rise is determined; and based on the range level and rate level, the temperature assessment data is generated.

4. The PCB board cooling control method based on real-time temperature sensing according to claim 3, characterized in that, When determining the cooling demand intensity value for each cooling zone, the following should be included: Based on the spatial coordinates, the overheated area is mapped to each cooling area; the basic cooling intensity is determined according to the risk level in the temperature assessment data; the cooling response time is determined in combination with the PCB board's moving speed; and the cooling demand intensity value of each cooling area is determined according to the basic cooling intensity and the cooling response time.

5. The PCB board cooling control method based on real-time temperature sensing according to claim 1, characterized in that, When determining the temperature deviation value, the following should be included: Obtain the expected outlet temperature under the same operating conditions from the historical cooling effect data; compare the expected outlet temperature with the actual outlet temperature to determine the basic temperature deviation; determine the temperature adjustment advance based on the PCB board's moving speed and the length of the cooling area; determine the temperature deviation value based on the basic temperature deviation and the temperature adjustment advance.

6. The PCB board cooling control method based on real-time temperature sensing according to claim 5, characterized in that, When correcting the operating parameters of each cooling zone based on the temperature deviation value, the following are included: The temperature deviation value is proportionally allocated to each cooling zone; the parameter adjustment amount is determined according to the proportion allocated to each cooling zone; based on the parameter adjustment amount, the fan speed, coolant flow rate and air duct guide angle of each cooling zone are corrected.

7. The PCB board cooling control method based on real-time temperature sensing according to claim 1, characterized in that, When acquiring temperature monitoring data and location information for several PCB boards, the following is included: Temperature monitoring data on the surface of the PCB board is collected by an array of temperature sensors installed along the conveyor belt. The position information of the PCB board during its movement is obtained by a position encoder installed along the conveyor belt.

8. The PCB board cooling control method based on real-time temperature sensing according to claim 7, characterized in that, When acquiring temperature monitoring data and location information for several PCB boards, the following is also included: The temperature monitoring data and location information are synchronized in time.

9. The PCB board cooling control method based on real-time temperature sensing according to claim 8, characterized in that, When identifying areas of temperature anomalies, the following should be included: Based on the spatial distribution of the temperature sensor array, a temperature distribution matrix is ​​constructed on the surface of the PCB board; the spatial rate of temperature change is determined according to the temperature difference between adjacent points in the temperature distribution matrix; the temperature gradient vector and its magnitude are determined according to the spatial rate of temperature change; the magnitude of the temperature gradient vector is compared with a gradient threshold; when the magnitude of the temperature gradient vector exceeds the gradient threshold, the current region is determined to be a temperature anomaly region.

10. A PCB board cooling control system based on real-time temperature sensing, used to apply the PCB board cooling control method based on real-time temperature sensing as described in any one of claims 1-9, characterized in that, include: The data acquisition unit is configured to acquire temperature monitoring data and location information of several PCB boards. Anomaly assessment unit is configured to perform temperature field spatial gradient calculation based on the temperature monitoring data to determine the temperature anomaly region; Analyze the temperature change trend at continuous time points; Based on the temperature anomaly areas and temperature change trends, overheated areas are identified, their spatial coordinates are marked, and their temperature change rate is determined. Temperature assessment data is generated based on the area ratio of the overheated areas and their temperature change rate. The command control unit is configured to determine the cooling demand intensity value of each cooling zone based on the spatial coordinates and temperature assessment data. Based on the cooling demand intensity value, adjust the operating parameters of each cooling zone and generate cooling control commands; The operation correction unit is configured to acquire the outlet temperature data of the PCB board at the outlet. When the outlet temperature data exceeds the safe temperature threshold, the temperature deviation value is determined based on historical cooling effect data and the PCB board moving speed, and the operating parameters of each cooling zone are corrected based on the temperature deviation value.

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