A tin paste printing and quality detection integrated system for circuit board production

Abstract

The application discloses a kind of tin paste printing and quality detection integration system for circuit board production, and relates to the technical field of circuit board detection, and its technical solution points are: including control module, printing module, quality detection module and feedback regulation module, effect is that control module carries out deviation analysis and comprehensive quality evaluation based on the tin paste quality standard preset in quality standard database, when detection data exceeds standard range, control module generates the instruction of adjustment printing pressure, doctor blade speed, doctor blade angle and tin paste supply amount, deviation is corrected in real time by feedback regulation module, to optimize printing quality;And when data is in standard range, system does not need to adjust, and printing module continues to run according to original parameter, forms efficient real-time closed loop control process, reduces process complexity by integrating detection and feedback mechanism, improves production efficiency, and realizes boundary integrity detection and parameter dynamic optimization by visual algorithm, effectively reduces defect rate.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of circuit board detection, more particularly, it relates to a tin paste printing and quality detection integrated system for circuit board production. BACKGROUND

[0002] In modern electronic manufacturing, circuit board (PCB) production is the core link of the entire electronic industry. With the miniaturization and high-density development of electronic components, tin paste printing as an important step in the circuit board welding process directly affects the success rate of subsequent soldering and the performance of the final product.

[0003] Traditional tin paste printing equipment and quality detection equipment are usually separated, after tin paste printing is completed, the circuit board needs to be transferred to an independent quality detection equipment to detect the tin paste thickness, printing position deviation and boundary shape, etc., which leads to the need for multiple steps to complete printing and detection, increasing the complexity of the process, reducing the overall efficiency of the production line, and the detection result lags behind the printing process, which cannot timely find problems in printing, leading to the accumulation of potential defects, and the printing parameters (such as pressure, scraper speed, tin paste supply amount, etc.) cannot be dynamically adjusted according to the detection result, resulting in insufficient quality control precision.

[0004] Therefore, in order to solve the above technical problems, the present application provides a tin paste printing and quality detection integrated system for circuit board production. SUMMARY

[0005] In view of the deficiencies in the prior art, the purpose of the present application is to provide a tin paste printing and quality detection integrated system for circuit board production.

[0006] To achieve the above purpose, the present application provides the following technical scheme: a tin paste printing and quality detection integrated system for circuit board production, comprising a control module, a printing module, a quality detection module and a feedback adjustment module;

[0007] The quality detection module is integrated in the running track of the printing module, the quality detection module detects the thickness, shape and printing position of the tin paste in real time through an industrial camera and a laser scanning device, and transmits the detection data to the control module;

[0008] The control module calculates the detection data based on the preset quality standard of tin paste printing, and evaluates the printing deviation by applying the following formula:

[0009] Tin paste thickness deviation formula:

[0010]

[0011] Wherein is the tin paste thickness deviation, The actual thickness of the solder paste detected by the quality inspection module. It is the preset standard solder paste thickness;

[0012] Solder paste position deviation formula:

[0013] ,

[0014] in, 、 are the lateral and longitudinal position deviations of the solder paste, , is the actual position coordinate of the solder paste to be detected, , is the standard position coordinate of solder paste;

[0015] Bias weight function:

[0016]

[0017] in, is the comprehensive evaluation value of deviation, is the thickness deviation weight factor, is the lateral deviation weight factor;

[0018] The control module is based on the deviation weight function The calculation result generates a parameter adjustment instruction, and transmits the instruction to the feedback adjustment module;

[0019] The feedback adjustment module is used to adjust the printing pressure of the printing module , scraper speed , scraper angle and solder paste supply , to reduce the total deviation evaluation value , so as to achieve the purpose of adjusting the printing module to the circuit board printing.

[0020] Preferably, the quality detection module is The visual algorithm realizes the detection of the boundary shape of solder paste. The visual algorithm uses the following formula to evaluate solder paste boundary integrity:

[0021]

[0022] in, is the solder paste boundary integrity indicator, is the actual area of ​​the solder paste boundary detected, For the preset standard solder paste boundary area, when When the system determines that the solder paste boundary is incomplete and generates an adjustment instruction, the is a preset integrity threshold.

[0023] Preferably, the control module comprises a data processing unit and a quality standard database, the data processing unit generates parameter adjustment instructions based on the following optimization algorithm:

[0024]

[0025] wherein, , are the adjusted printing pressure and squeegee speed, respectively, , are the current printing pressure and squeegee speed, , is a preset adjustment factor.

[0026] Preferably, the feedback adjustment module adjusts at least one of the following printing parameters through a dynamic learning algorithm:

[0027]

[0028] wherein, is the adjusted solder paste supply amount, is the current solder paste supply amount, is the learning rate, is the solder paste boundary integrity error.

[0029] Preferably, the control module applies a feedback control algorithm to predict possible printing defects based on continuously detected deviation data, using the following prediction formula:

[0030]

[0031] wherein, is the predicted deviation comprehensive evaluation value, is the current deviation comprehensive evaluation value, is the rate of change of deviation over time, is a prediction factor.

[0032] When , the system generates adjustment instructions in advance, and the is a preset deviation threshold.

[0033] Preferably, the control module and the quality detection module are connected through wireless communication, the industrial camera and the laser scanning device in the quality detection module send the collected data to the control module through wireless communication, analyze the data of the solder paste thickness, position and boundary shape according to the preset solder paste quality standard in the quality standard database, and judge whether there is deviation. If the quality data is out of the standard range, generate corresponding adjustment instructions, if the data is within the standard range, no adjustment is needed, continue to run.

[0034] Preferably, the adjustment instruction generation logic comprises:

[0035] If the solder paste thickness deviation is large, instructions for adjusting the printing pressure and the solder paste supply amount are generated;

[0036] If the solder paste position deviation is large, instructions for adjusting the squeegee angle or the moving speed are generated;

[0037] If the boundary shape is incomplete, instructions for optimizing the solder paste supply amount are generated;

[0038] Meanwhile, based on the continuously detected data, the upcoming printing defects are predicted, and the adjustment instructions are generated in advance to prevent the subsequent defects from being enlarged.

[0039] Preferably, the feedback adjustment module receives and executes the adjustment instructions through the control module, and the adjustment instructions comprise adjusting the following parameters of the printing module:

[0040] The printing pressure, i.e., the printing intensity on the circuit board during printing; the squeegee speed, i.e., the moving speed of the squeegee for wiping the solder paste; the squeegee angle, i.e., the inclination angle of the squeegee during the solder paste printing; and the solder paste supply amount, i.e., the actual amount of the solder paste adjusted according to the detection result of the boundary shape.

[0041] Compared with the prior art, the present application has the following beneficial effects:

[0042] In the present application, the quality detection module is integrated in the running track of the printing module, the real-time detection of the solder paste thickness, position and boundary shape is realized by combining the industrial camera and the laser scanning device, the detection data are transmitted to the control module through wireless communication, the control module performs deviation analysis and comprehensive quality evaluation based on the preset solder paste quality standards in the quality standard database, when the detection data are out of the standard range, the control module generates instructions for adjusting the printing pressure, the squeegee speed, the squeegee angle and the solder paste supply amount, and the feedback adjustment module is used to correct the deviation in real time, so as to optimize the printing quality; when the data are within the standard range, the system does not need to be adjusted, and the printing module continues to operate according to the original parameters, forming an efficient real-time closed-loop control process. The visual algorithm realizes the boundary integrity detection and the dynamic parameter optimization, and effectively reduces the defect rate. BRIEF DESCRIPTION OF DRAWINGS

[0043] The drawings described herein are used to provide further understanding of the present application, and form a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application, and do not constitute an improper limitation on the present application. In the drawings:

[0044] Figure 1 System flowchart of the present application;

[0045] Figure 2 Module relationship diagram in the present application. DETAILED DESCRIPTION

[0046] As shown in Figure 1 and Figure 2 The present application provides a tin paste printing and quality detection integrated system for circuit board production, comprising a control module, a printing module, a quality detection module and a feedback adjustment module.

[0047] Printing module: performs tin paste printing task, uniformly spreads tin paste on the surface of the circuit board through a doctor blade;

[0048] Quality detection module: integrated in the running track of the printing module, used for real-time detection of the quality data after tin paste printing, the module comprising an industrial camera and a laser scanning device;

[0049] Control module: used for receiving the data collected by the quality detection module, calculating the deviation of the detection data based on the preset standard of tin paste quality and generating adjustment instructions;

[0050] Feedback adjustment module: dynamically adjusts the printing pressure, doctor blade speed, doctor blade angle and tin paste supply amount of the printing module according to the adjustment instructions generated by the control module, forming a closed-loop control.

[0051] The quality detection module is integrated in the running track of the printing module, and the quality detection module detects the thickness, shape and printing position of the tin paste in real time through the industrial camera and the laser scanning device, and transmits the detection data to the control module;

[0052] The control module and the quality detection module are connected through wireless communication, and the wireless communication mode selected in the present embodiment is an industrial wireless protocol (such as wireless HART or ISA100, which is not described in detail in the prior art), which is dedicated to industrial automation scenarios and has high reliability;

[0053] The control module calculates the detection data based on the preset quality standard of tin paste printing, and applies the following formula to evaluate the printing deviation:

[0054] Tin paste thickness deviation formula:

[0055]

[0056] Wherein is the tin paste thickness deviation, is the actual thickness of the tin paste detected by the quality detection module, is the preset standard tin paste thickness;

[0057] It should be noted that the laser scanning device in the quality detection module of this embodiment scans the surface of the solder paste at a high frequency to obtain the thickness value of the solder paste, and the detection data is sent to the control module and compared with the preset standard thickness to calculate the thickness deviation .

[0058] Solder paste position deviation formula:

[0059] ,

[0060] wherein, , are the lateral and longitudinal position deviations of the solder paste, , is the actual position coordinate of the detected solder paste, , is the standard position coordinate of the solder paste;

[0061] It should be noted that in this embodiment, the control module predicts that the position of a batch of circuit boards may deviate during continuous production by continuously detecting data streams. Through the position deviation detection algorithm, the system detects that the position deviation value and is approaching the preset upper limit of tolerance, = 0.09mm (the upper limit of tolerance is 0.1mm), to prevent the deviation from further expanding and causing uneven solder paste coverage, the control module generates an optimization instruction to adjust the scraper speed and scraper inclination angle in advance and sends it to the feedback adjustment module. After the feedback adjustment module adjusts the parameters, the printing position of the solder paste is re-kept within the standard range, ensuring the stability of the subsequent process.

[0062] The quality detection module detects the shape of the solder paste boundary by a visual algorithm, and the visual algorithm uses the following formula to evaluate the integrity of the solder paste boundary:

[0063]

[0064] wherein, is the solder paste boundary integrity index, is the actual area of the detected solder paste boundary, is the preset standard solder paste boundary area, when the system judges that the solder paste boundary is incomplete and generates an adjustment instruction, is the preset integrity threshold

[0065] In this embodiment, based on the solder paste printing image data collected by the industrial camera, The visual algorithm first pre-processes the image, including denoising, contrast enhancement and edge detection, then accurately extracts the actual boundary area of the solder paste printing through a boundary recognition algorithm (such as existing technologies based on Canny edge detection or deep learning-based boundary extraction algorithm), and calculates the actual area of the solder paste through pixel area At the same time, the system extracts the preset standard solder paste area from the quality standard database As a contrast benchmark, according to the two data, the system calculates the boundary integrity index to quantify the integrity degree of the solder paste printing boundary;

[0066] When the boundary integrity index is less than the preset integrity threshold (e.g. =0.95), the system judges that the solder paste boundary is not complete, and there may be defects (such as irregular, broken or missing solder paste edges), in which case the system will generate boundary optimization adjustment instructions, including instructions to optimize the amount of solder paste supply, adjust the angle or speed of the squeegee, to improve the shape of the solder paste boundary. The generated instructions are sent to the feedback adjustment module through wireless communication, and the adjustment operation is performed by the feedback adjustment module, and the printing parameters are optimized in real time, so as to ensure the integrity and quality stability of the solder paste boundary. The whole process is executed in real time under closed-loop control, ensuring continuous optimization of printing quality.

[0067] Deviation weight function:

[0068]

[0069] Wherein, is the deviation comprehensive evaluation value, is the thickness deviation weight factor, is the lateral deviation weight factor;

[0070] The control module generates parameter adjustment instructions according to the calculation results of the deviation weight function , and transmits the instructions to the feedback adjustment module;

[0071] The adjustment instruction generation logic includes:

[0072] If the solder paste thickness deviation is large, generate instructions to adjust the printing pressure and the amount of solder paste supply;

[0073] If the solder paste position deviation is large, generate instructions to adjust the angle or movement speed of the squeegee;

[0074] If the boundary shape is not complete, that is, when the boundary integrity index is less than the threshold , generate instructions to optimize the amount of solder paste supply;

[0075] Meanwhile, based on the continuously detected data, the feedback adjustment module predicts the upcoming printing defects and generates adjustment instructions in advance to prevent the subsequent defects from expanding.

[0076] The feedback adjustment module adjusts the printing pressure , the squeegee speed , the squeegee angle , and the solder paste supply amount of the printing module to reduce the deviation sum evaluation value , so as to achieve the adjustment purpose of the printing module for the circuit board printing.

[0077] The control module includes a data processing unit and a quality standard database, and the data processing unit generates parameter adjustment instructions based on the following optimization algorithm:

[0078]

[0079] wherein, , are the adjusted printing pressure and squeegee speed, respectively, , are the current printing pressure and squeegee speed, respectively, , is a preset adjustment factor.

[0080] The feedback adjustment module adjusts at least one of the following printing parameters through a dynamic learning algorithm:

[0081]

[0082] wherein, is the adjusted solder paste supply amount, is the current solder paste supply amount, is a learning rate, is a solder paste boundary integrity error.

[0083] The feedback adjustment module receives and executes the adjustment instructions through the control module, and the adjustment instructions include adjusting the following parameters of the printing module:

[0084] Printing pressure adjustment: according to the adjustment instructions, the pressure of the printing squeegee is changed to optimize the thickness distribution of the solder paste on the surface of the circuit board;

[0085] Squeegee speed adjustment: the moving speed of the squeegee is adjusted to ensure uniform distribution of the solder paste;

[0086] Squeegee angle adjustment: the inclination angle of the squeegee is changed to improve the printing form of the solder paste;

[0087] Solder paste supply amount adjustment: according to the boundary detection data, the supply amount of the solder paste is adjusted in real time , ensure the tin paste printing boundary integrity.

[0088] It should be noted that the embodiment is aimed at the laser scanning device in the quality detection module in the circuit board production process, which monitors the thickness deviation of the tin paste in real time. The detection data shows that the actual thickness deviation is greater than 0.1 mm from the preset standard thickness, which may cause problems such as insecure welding or virtual welding of subsequent components. The detection data is transmitted to the control module through wireless communication, the control module immediately starts the thickness deviation analysis algorithm, generates an optimization instruction for adjusting the printing pressure, and sends it to the feedback adjustment module. The feedback adjustment module dynamically reduces the pressure value of the scraper according to the instruction, so that the tin paste thickness is uniformly distributed, and then the thickness deviation is gradually reduced to ≤0.02 mm through continuous detection verification, and the thickness deviation is gradually reduced to ≤0.02 mm.

[0089] The embodiment is applicable to the tin paste boundary fracture or irregular phenomenon in some circuit board areas captured by the industrial camera in the same batch production, and the visual algorithm analysis is performed. The system calculates the boundary integrity index The actual detected tin paste area is only 90% of the standard area. The system judges that the boundary is not complete, which may cause the solder to not uniformly cover the pad during the welding process, affecting the welding quality. The control module generates an adjustment instruction for optimizing the tin paste supply amount based on the deviation calculation result, and transmits the instruction to the feedback adjustment module. The feedback adjustment module executes immediately, increases the tin paste supply amount and slightly adjusts the scraper angle , realizes the compensation optimization of the boundary, and restores the integrity of the tin paste printing to the standard.

[0090] The control module applies a feedback control algorithm to predict possible printing defects based on the deviation data of continuous detection, using the following prediction formula:

[0091]

[0092] Among them, is the predicted deviation comprehensive evaluation value, is the current deviation comprehensive evaluation value, is the rate of change of the deviation over time, is the prediction factor;

[0093] When , the system generates an adjustment instruction in advance, is the preset deviation threshold;

[0094] ​​​​​​In this embodiment, the quality detection module continuously collects real-time data of the solder paste printing and transmits the data to the control module. The control module generates adjustment instructions after analyzing the deviation and feeds back the instructions to the adjustment module for real-time adjustment, forming a closed-loop control.

[0095] The control module and the quality detection module are connected through wireless communication. The industrial camera in the quality detection module collects image data of the solder paste printing in real time, and the laser scanning device synchronously acquires the thickness information of the solder paste. The quality data such as the detected thickness, position, and boundary shape are transmitted to the control module through wireless communication. After receiving the data, the control module compares and analyzes the data with the preset solder paste quality standard in the quality standard database, calculates the deviation value, and evaluates the comprehensive quality state of the solder paste printing. If the analysis result shows that the quality data is out of the standard range, the control module will generate corresponding adjustment instructions in real time, including adjusting the printing pressure, the doctor blade speed, the doctor blade angle, and the solder paste supply amount, etc. The instructions are sent to the feedback adjustment module through wireless communication. The feedback adjustment module performs dynamic adjustment according to the instructions to correct the deviation, thereby optimizing the printing quality. If the detection data is within the standard range, the system does not need to adjust, and the printing module continues to run according to the original parameters, forming an efficient real-time closed-loop control process.

[0096] In summary, by integrating the quality detection module into the running track of the printing module, the industrial camera and the laser scanning device are used to realize real-time detection of the solder paste thickness, position, and boundary shape. The detection data are transmitted to the control module through wireless communication. The control module performs deviation analysis and comprehensive quality evaluation based on the preset solder paste quality standard in the quality standard database. When the detection data is out of the standard range, the control module generates instructions to adjust the printing pressure, the doctor blade speed, the doctor blade angle, and the solder paste supply amount. The feedback adjustment module corrects the deviation in real time, thereby optimizing the printing quality. When the data is within the standard range, the system does not need to adjust, and the printing module continues to run according to the original parameters, forming an efficient real-time closed-loop control process. Compared with the traditional solder paste printing and quality detection equipment separation method mentioned in the background art, the present application reduces the process complexity and improves the production efficiency by integrating the detection and feedback mechanism. The visual algorithm realizes boundary integrity detection and dynamic parameter optimization, effectively reducing the defect rate. The visual algorithm realizes boundary integrity detection and dynamic parameter optimization, effectively reducing the defect rate.

[0097] The above merely describes preferred embodiments of the present application, and is not intended to limit the present application in any form; any person skilled in the art can easily implement the present application according to the drawings and the above description; however, any person skilled in the art can make some changes, modifications and equivalent changes of the above disclosed technical contents without departing from the technical solution of the present application, and the equivalent embodiments of the present application are still within the protection scope of the present application.

Claims

1. An integrated system for solder paste printing and quality inspection for circuit board production, characterized by: It includes a control module, a printing module, a quality detection module and a feedback adjustment module; The quality inspection module is integrated into the running track of the printing module. The quality inspection module uses an industrial camera and a laser scanning device to perform real-time inspection of the thickness, shape, and printing position of the solder paste, and transmits the inspection data to the control module. The control module calculates the inspection data based on the preset quality standard of solder paste printing and applies the following formula to evaluate the printing deviation: Solder paste thickness deviation formula: ； in is the solder paste thickness deviation, The actual thickness of the solder paste detected by the quality inspection module. It is the preset standard solder paste thickness; Solder paste position deviation formula: ， ； in, 、 are the lateral and longitudinal position deviations of the solder paste, , is the actual position coordinate of the solder paste to be detected, , is the standard position coordinate of solder paste; Bias weight function: ； in, is the comprehensive evaluation value of deviation, is the thickness deviation weight factor, is the lateral deviation weight factor; The control module is based on the deviation weight function The calculation result generates a parameter adjustment instruction, and transmits the instruction to the feedback adjustment module; The feedback adjustment module is used to adjust the printing pressure of the printing module , scraper speed , scraper angle and solder paste supply , to reduce the total deviation evaluation value , so as to achieve the purpose of adjusting the printing module to the circuit board printing.

2. The integrated system for solder paste printing and quality inspection for circuit board production according to claim 1, characterized in that: The quality detection module is The visual algorithm realizes the detection of the boundary shape of solder paste. The visual algorithm uses the following formula to evaluate solder paste boundary integrity: ； in, is the solder paste boundary integrity indicator, is the actual area of ​​the solder paste boundary detected, For the preset standard solder paste boundary area, when When the system determines that the solder paste boundary is incomplete and generates an adjustment instruction, the is the preset integrity threshold.

3. The integrated system for solder paste printing and quality inspection for circuit board production according to claim 1 or 2, characterized in that: The control module includes a data processing unit and a quality standard database. The data processing unit generates parameter adjustment instructions based on the following optimization algorithm: ； in, 、 are the adjusted printing pressure and scraper speed, 、 is the current printing pressure and scraper speed, 、 is the preset adjustment factor.

4. The integrated system for solder paste printing and quality inspection for circuit board production according to claim 1 or 3, characterized in that: The feedback adjustment module adjusts at least one of the following printing parameters through a dynamic learning algorithm: ； in, is the adjusted solder paste supply amount, is the current solder paste supply, is the learning rate, is the solder paste boundary integrity error.

5. The integrated system for solder paste printing and quality inspection for circuit board production according to claim 1 or 4, characterized in that: The control module applies a feedback control algorithm to predict possible printing defects based on continuously detected deviation data, using the following prediction formula: ； in, is the comprehensive evaluation value of the predicted deviation, is the comprehensive evaluation value of the current deviation, is the rate of change of the deviation over time, is a predictor; when When the system generates an adjustment instruction in advance, the is the preset deviation threshold.

6. The integrated system for solder paste printing and quality inspection for circuit board production according to claim 5, characterized in that: The control module and the quality inspection module are connected via wireless communication. The industrial camera and laser scanning device in the quality inspection module send the collected data to the control module via wireless communication. According to the solder paste quality standards preset in the quality standard database, the data on solder paste thickness, position and boundary shape are analyzed to determine whether there is a deviation. If the quality data exceeds the standard range, a corresponding adjustment instruction is generated. If the data is within the standard range, no adjustment is required and the operation continues.

7. The integrated system for solder paste printing and quality inspection for circuit board production according to claim 6, characterized in that: The adjustment instruction generation logic includes: If the solder paste thickness deviation is large, generate instructions to adjust the printing pressure and solder paste supply amount; If the solder paste position deviation is large, an instruction to adjust the scraper angle or moving speed is generated; If the boundary shape is incomplete, generate instructions to optimize the solder paste supply amount; At the same time, based on the data from continuous inspection, it predicts impending printing defects and generates adjustment instructions in advance to prevent subsequent defects from expanding.

8. The integrated system for solder paste printing and quality inspection for circuit board production according to claim 7, characterized in that: The feedback adjustment module receives and executes adjustment instructions via data transmitted by the control module. The adjustment instructions include adjusting the following parameters of the printing module: Printing pressure is to adjust the printing force on the circuit board during printing; scraper speed is to adjust the movement speed of the scraper when scraping the solder paste; scraper angle is the tilt angle of the scraper during solder paste printing; solder paste supply amount is to adjust the actual amount of solder paste used according to the detection results of the boundary shape.

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