Intelligent sensing high-precision solder paste printing equipment and control system

Abstract

The invention provides intelligent sensing high-precision solder paste printing equipment and a control system, and relates to the technical field of circuit board printing, the intelligent sensing high-precision solder paste printing equipment comprises an outer protective frame, a conveyor and a main controller, a control main system is implanted in the main controller, the main controller is installed on one side of the front face of the outer protective frame, and a material box is placed on the side, close to the conveyor, in the outer protective frame; a plate shell is placed in the material box, a circuit board is placed in the plate shell, side holes are formed in the two sides of the plate shell, clamping controllers are installed on the two sides in the plate shell, and high-precision detection and solder paste brushing on the circuit board are achieved through advanced technologies such as a high-definition camera, an image recognition algorithm and a thickness detector. For example, a high-definition camera can capture fine defects and characteristics on the circuit board, the accuracy of marking and paste brushing is ensured, and meanwhile, various sensors and a control system can accurately control the use amount, thickness and position of the solder paste.

Description

Technical Field

[0001] The present invention relates to the technical field of circuit board printing, and in particular to intelligent sensing high-precision solder paste printing equipment and a control system. Background Art

[0002] According to a solder paste printing device disclosed in Chinese patent number "CN213861254U", the solder paste printing device includes a frame, a conveying device and a paste brushing assembly: the frame has a printing station; the conveying device is arranged on the frame, and is used to transport the plate to be printed to the printing station; the paste brushing assembly is arranged on the frame and above the conveying device, and the paste brushing assembly is arranged corresponding to the printing station, and is used to print the plate to be printed; wherein the printing station has a bearing part for bearing the plate to be printed, and at least one of the paste brushing assembly and the bearing part is arranged to be movable in the up and down direction. The utility model aims to provide a solder paste printing device, aiming to solve the problem of unstable product quality caused by manual solder paste brushing.

[0003] According to a solder paste printer disclosed in Chinese patent number "CN 113524886 A", the machine includes a frame, an operating table, a workbench, a printing lifting mechanism, a cutter head, a cutter head driving mechanism, a steel mesh, a slide rail, and a support arm. The steel mesh includes a square support frame and a screen plate located inside the support frame. A cavity layer is provided in the support frame, and a liquid leakage port is provided on the inner wall of the peripheral side of the support frame. A storage frame is provided in the cavity layer, and through holes are provided at both ends of the support frame and corresponding to the position where each clamping plate abuts. A column passing through the through hole is provided on the upper side of the storage frame, and a cross bar connected to the upper ends of multiple columns and for the clamping plate to abut is provided at one end of the storage frame. A return spring is connected to the lower side of the storage frame and corresponding to the bottom of each column.

[0004] The existing technology has the following problems in actual use:

[0005] 1. The current printed circuit board may not have high enough recognition accuracy in complex environments during intelligent recognition. For example, in poor light conditions, recognition errors or inaccuracies may occur, affecting the accuracy of printing and resulting in failure to print within the required range. Manual control of the equipment is required every time, and automatic adjustment is not possible;

[0006] 2. The existing equipment does not have the function of filling materials. When it is found that the glue coating is uneven at a certain position on the circuit board, it cannot automatically make up for it;

[0007] 3. The existing solder paste printing device components are not easy to disassemble, and maintenance and repair are difficult. At the same time, the existing technology may not be adaptable enough to PCBs of different types, sizes and materials.

[0008] Therefore, intelligent sensing high-precision solder paste printing equipment and control systems are needed to solve the above problems. Summary of the invention

[0009] Technical issues solved

[0010] In view of the shortcomings of the prior art, the present invention provides an intelligent sensing high-precision solder paste printing device and control system, which solves the problem that the current printed circuit board may not have high enough recognition accuracy for PCB in complex environments during intelligent recognition. For example, in poor light conditions, recognition errors or inaccuracies may occur, affecting the accuracy of printing and resulting in failure to print within the required range. Manual control of the device is required every time, and automatic adjustment is not possible.

[0011] Technical Solution

[0012] To achieve the above objectives, the present invention is implemented through the following technical solutions: intelligent sensing high-precision solder paste printing equipment and control system, including an outer protective frame, a conveyor and a main controller, the main controller is implanted with a control main system, the main controller is installed on one side of the front of the outer protective frame, a material box is placed on the inner side of the outer protective frame close to the conveyor, a board shell is placed inside the material box, a circuit board is placed inside the board shell, side holes are opened on both sides of the board shell, clamping controllers are installed on both sides of the board shell, the clamping controller, the end of the clamping controller is electrically connected to a clamping telescopic part, the end of the clamping telescopic part is clamped with a clamping strip, a proximity sensor is embedded in the middle of the board shell, the external bolts on the top of the conveyor are connected to a detection cover, one side of the detection cover is bolted to a marking cover, and one side of the marking cover is bolted to a paste brush rack.

[0013] Preferably, a material picking and conveying motor group is installed on one side of the top of the outer protective frame, and the output end of the material picking and conveying motor group passes through the interior of the outer protective frame. The external thread of the material picking and conveying motor group is connected to a sliding plate, and the sliding plate is slidably connected to the top of the outer protective frame. A lifting assembly is installed at the bottom of the sliding plate, and a material picking cover is clamped at the bottom of the lifting assembly.

[0014] Preferably, an infrared sensor is embedded in the top of the material picking cover, and material picking controllers are installed on both sides of the material picking cover. The ends of the material picking controllers are electrically connected to the material picking telescopic parts, and the ends of the material picking telescopic parts are clamped with clamping heads, and the clamping heads and side holes are adapted to each other. A convex point is provided on the top of the middle end of the conveyor, and the bottom of the plate shell is clamped with the convex point on the top of the conveyor.

[0015] Preferably, an image transmitter is installed on one side of the detection cover, a card frame is bolted to the middle of the top of the detection cover, a rotating shaft is movably connected inside the card frame, a rotating motor is installed on one side of the card frame, an end of the rotating motor is transmission-connected to the rotating shaft, a connecting shaft is threadedly connected to the bottom end of the rotating shaft, a mounting plate is clamped on the bottom of the connecting shaft, a high-definition camera is installed on the bottom of the mounting plate, and a first proximity sensor is installed on one side of the top of the detection cover.

[0016] Preferably, a mark control end is installed on one side of the top of the mark cover, and a mark lateral movement control end is installed on one side of the mark cover, the output end of the mark lateral movement control end passes through the interior of the mark cover, the output end of the mark lateral movement control end is externally threadedly connected to a drive block, a longitudinal sliding block is installed at the bottom of the drive block, the bottom of the longitudinal sliding block is electrically connected to a telescopic cylinder assembly, and a pressure plate is clamped at the bottom of the telescopic cylinder assembly.

[0017] Preferably, a mark is provided on the top of the circuit board, the color of the mark is red, and the shape of the mark is rectangular.

[0018] Preferably, a mixing drum is installed on one side of the top of the paste brush rack, a mixing motor is installed on the top of the mixing drum, an observation port is opened on the front of the bottom of the mixing drum, and a brush control end is installed on the other side of the top of the paste brush rack.

[0019] Preferably, a brush lateral movement control end is installed on one side of the outside of the brush paste rack, and the output end of the brush lateral movement control end passes through the interior of the brush paste rack. The output end of the brush lateral movement control end is externally threadedly connected to a moving plate, and the moving plate and the top of the brush paste rack are slidingly connected. A longitudinal moving block is installed at the bottom of the moving plate, and a collector is clamped at the bottom end of the longitudinal moving block. A thickness detector is installed on the front of the collector, and one side of the collector is connected to a mixing drum. A second proximity sensor is embedded on one side of the bottom of the brush paste rack.

[0020] Preferably, a spray pump is installed on one side of the front bottom of the collector, the end flange of the spray pump is connected to a pipeline, the bottom bolts of the collector are connected to a measuring bucket, a metering pump is installed on the top of one side of the measuring bucket, a pipeline is connected between one side of the metering pump and the collector, a discharge pipe is provided in the middle of the bottom end of the measuring bucket, a scraper is clamped on one side of the bottom of the measuring bucket, a roller plate is clamped on the other side of the bottom of the measuring bucket, a roller is installed on the bottom of the roller plate, and the bottom heights of the discharge pipe, scraper and roller plate are flush.

[0021] Preferably, the main control system includes a recognition and marking system, a marking scanning system, a gluing control system and a defect recognition system. The specific settings and workflow of the subsystems in the main control system are as follows:

[0022] Sp1. The identification and marking system includes an image acquisition module, an image processing module, a mark recognition module and a mark control module. The high-definition camera takes a picture of the original circuit board and then transmits it to the image acquisition system. The image acquisition system converts the acquired image into a digital graphic signal. When the high-definition camera is aimed at the circuit board, the reflected light from various parts of the circuit board enters the interior of the high-definition camera through the lens of the high-definition camera, thereby forming an image that is transmitted to the image acquisition module. The image acquisition module is directly implanted in the high-definition camera and converts the acquired image into a digital image signal. The function of the lens is similar to that of a convex lens. It can converge light so that the light emitted by objects at different positions on the circuit board can form a clear image on the imaging plane of the high-definition camera. After the light passes through the lens, an inverted real image is formed on the imaging sensor of the high-definition camera (such as a CCD or CMOS sensor). The imaging sensor is composed of many tiny photosensitive elements. These photosensitive elements can convert the received light signals into electrical signals. Each photosensitive element corresponds to a pixel in the image, and the intensity of the light it receives determines the size of the output electrical signal. The analog electrical signal output by the imaging sensor is converted into a digital signal through an analog-to-digital converter (ADC). The digital signal is stored in the camera's memory in a specific format or directly transmitted to an external device for processing. In this way, the actual appearance of the circuit board is converted into a digital image signal, in which the value of each pixel represents the brightness or color information of the point.

[0023] Sp2, the image processing module receives the digital graphic signal converted by the image acquisition module. The image preprocessing module preprocesses the acquired image, including denoising and contrast enhancement operations to improve the image quality. The denoising adopts the mean filtering method. The detailed steps are as follows:

[0024] For each pixel in the image, the average value of the pixels in its neighborhood is taken as the new value of the pixel. The size of the neighborhood is usually a square window, and the side length of the window can be adjusted as needed.

[0025] For each pixel in the image, take the average value of the pixel values ​​in its neighborhood as the new value of the pixel. The size of the neighborhood is usually a square window, and the side length of the window can be adjusted as needed. The specific adjustment is as follows: Let the original image be I(x, y), and the image after mean filtering be I mean The size of the (x,y) neighborhood is m×n, then

[0026]

[0027] in

[0028] The values ​​of the m×n pixels around the central pixel I(x,y) are summed and divided by the total number of pixels in the neighborhood mn. The result is used as the new value of the central pixel, which can smooth the image and reduce the impact of random noise.

[0029] Where i and j are the pixel coordinate offsets traversed in the neighborhood.

[0030] Enhance contrast by adjusting the grayscale histogram of the image to make the grayscale distribution of the image more uniform, thereby improving the contrast. Specifically, histogram equalization maps the grayscale range of the original image to a wider grayscale range, making the number of pixels of different grayscale levels in the image closer.

[0031] Assume that the gray level of the original image is r and its probability density function is p r (r), the gray level of the image after histogram equalization is s, then Where w is the integration variable.

[0032] In histogram equalization: It means that the original gray level r is transformed into a new gray level s by integration, so that the gray distribution of the image is more uniform.

[0033] Sp3, the marking control module extracts and analyzes the image processed by the image processing module, performs binarization on the image obtained by edge detection, sets the value of the edge pixel to 1, and the value of the non-edge pixel to 0, and starts from an edge pixel in the image and tracks along the edge pixel until it returns to the starting point to form a closed contour. The contour tracking algorithm uses the eight-neighborhood tracking method. During the tracking process, the pixel coordinates of each contour are recorded, and then the contour area and contour perimeter are calculated:

[0034] Calculate the area of ​​a contour:

[0035] For each extracted contour, its area can be calculated using the following formula:

[0036] Area = Σ (x,y)∈轮廓 1. Count the number of pixels within the contour.

[0037] Calculate the contour perimeter:

[0038] The perimeter of the contour is obtained by calculating the sum of the distances between adjacent pixels on the contour.

[0039] For adjacent pixels (x1, y1) and (x2, y2), the distance between them can be calculated using the Euclidean distance formula:

[0040] By combining the extracted contour with the size, layout and component position information in the circuit board design file, the range where solder paste needs to be printed is determined, and then the labeler is controlled by the marking control program to label the range where solder paste needs to be printed. After labeling, the range where solder paste needs to be printed will be framed, and the label color is red for easy subsequent identification.

[0041] Sp4. The mark scanning system collects the image of the bottom circuit board, and uses an image recognition algorithm to detect the position of the mark in the image based on the characteristics of the mark, including specific color, shape and pattern. The mark is a specific color, and a color segmentation detection algorithm can be used to locate the mark. The pixels in the image are divided into two categories: mark color and non-mark color. Then, based on the detected mark position, the printing range indicated by the mark is determined, and then the mark range in the image coordinate system is converted into coordinates in the actual printing device coordinate system. The converted coordinate information is sent to the gluing control system. The marked circuit board is easier to identify and less affected by the environment.

[0042] Beneficial Effects

[0043] The present invention provides intelligent sensing high-precision solder paste printing equipment and control system. It has the following beneficial effects:

[0044] 1. The entire device of the present invention realizes high-precision detection and solder paste brushing of circuit boards through advanced technologies such as high-definition cameras, image recognition algorithms, and thickness detectors. For example, high-definition cameras can capture subtle defects and features on circuit boards to ensure the accuracy of marking and paste brushing. At the same time, various sensors and control systems can accurately control the amount, thickness and position of solder paste, improving the printing quality. The equipment is highly automated, and the entire process from circuit board material collection, detection, marking to paste brushing does not require human intervention, greatly improving production efficiency and reducing human errors. For example, the material collection and conveying motor group, sliding plate, lifting assembly and other components work together to automatically complete the collection and placement of circuit boards; various control terminals and actuators in the marking cover and paste brushing rack can automatically perform marking and paste brushing operations according to preset programs.

[0045] 2. The device in the present invention can adapt to circuit boards of different types and sizes. For example, the clamping controller and the clamping strips in the board shell can be adjusted according to the size of the circuit board to ensure that circuit boards of different sizes can be stably fixed. At the same time, the positions and parameters of components such as the material collection cover, the detection cover, the marking cover and the paste brushing rack can also be adjusted according to the size and shape of the circuit board, which improves the versatility of the equipment and allows the equipment to be flexibly adjusted according to different production needs. For example, the marking control end can set different marking contents and parameters to meet the marking requirements of circuit boards of different batches or models; the brushing control end can adjust the amount, thickness and brushing speed of solder paste and other parameters to adapt to different printing requirements. In addition, the equipment can also achieve different marking and paste brushing methods by replacing different marking devices and paste brushing devices, thereby improving the adaptability of the equipment.

[0046] 3. The equipment in the present invention is equipped with a defect recognition system, which can analyze the detected thickness, determine whether the solder paste is uniform, and calculate the specific parameters for re-coating. This helps to promptly discover and correct quality problems in the printing process and improve the quality stability of the product. For example, when the uneven thickness of the solder paste is detected, the system can automatically calculate the position and amount of re-coating required, and then accurately re-coat through the discharge pipe and scraper, roller plate and other components to ensure that the thickness of the solder paste on the circuit board is uniform and consistent, and the various components of the equipment work together with good stability. For example, the conveyor can stably transport the circuit board to ensure the accurate transfer of the circuit board between various operating areas; the installation and operation of components such as the material collection cover, detection cover, marking cover and paste brush rack are stable and reliable, and are not prone to failure. At the same time, the equipment also uses high-quality materials and advanced manufacturing processes to improve the durability and reliability of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 It is the overall structure diagram of the present invention;

[0048] Figure 2 It is an overall front view of the present invention;

[0049] Figure 3 It is a top structural diagram of the conveyor of the present invention;

[0050] Figure 4 It is the internal structure diagram of the plate shell of the present invention;

[0051] Figure 5 It is the internal structure diagram of the material taking cover of the present invention;

[0052] Figure 6 This is a diagram showing the internal structure of the detection cover of the present invention;

[0053] Figure 7 It is the internal structure diagram of the marking cover of the present invention;

[0054] Figure 8 It is a marking schematic diagram of the present invention;

[0055] Fig. 9 This is a diagram showing the internal structure of the paste brush holder of the present invention;

[0056] Fig.10 It is an axonometric view of the paste brush stand of the present invention;

[0057] Fig.11 It is a component structure diagram of the present invention;

[0058] Fig.12 It is the installation structure diagram of the measuring bucket device of the present invention;

[0059] Fig.13 It is the installation structure diagram of the spray pump of the present invention;

[0060] Fig.14 This is a diagram showing the structure of the main control system of the present invention;

[0061] Fig.15 It is a workflow diagram of the identification marking system of the present invention;

[0062] Fig.16 It is a flow chart of the marking scanning system and the gluing control system of the present invention;

[0063] Fig.17 This is a working flow chart of the defect recognition system of the present invention.

[0064] Among them: 1. outer frame; 2. transmission controller; 3. conveyor; 4. plate shell; 5. material box; 6. material cover; 7. material conveying motor group; 8. dustproof net; 9. sliding plate; 10. lifting assembly; 11. brush paste rack; 12. marking cover; 13. detection cover; 14. main controller; 15. side hole; 16. material controller; 17. material retractable part; 18. clamping head; 19. infrared sensor; 20. clamping controller; 21. clamping retractable part; 22. clamping strip; 23. proximity sensor; 24. image transmitter; 25. card frame; 26. rotating shaft; 27. first proximity sensor; 28. rotating motor; 2 9. Coupling; 30. Mounting plate; 31. High-definition camera; 32. Observation port; 33. Mixing drum; 34. Mixing motor; 35. Brushing control end; 36. Brushing lateral control end; 37. Moving plate; 38. Longitudinal moving block; 39. Collector; 40. Measuring pump; 41. Measuring bucket; 42. First proximity sensor; 43. Scraper; 44. Discharge pipe; 45. Roller plate; 46. Marking control end; 47. Marking lateral control end; 48. Longitudinal sliding block; 49. Telescopic cylinder assembly; 50. Press plate; 51. Drive block; 52. Circuit board; 53. Mark; 54. Spray pump; 55. Thickness detector. DETAILED DESCRIPTION

[0065] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Specific embodiment one:

[0067] like Figure 1-17 As shown, the intelligent sensing high-precision solder paste printing equipment and control system include an outer protective frame 1, a conveyor 3 and a main controller 14, wherein the main controller 14 is implanted with a control main system, the main controller 14 is installed on one side of the front of the outer protective frame 1, a material box 5 is placed on the inner side of the outer protective frame 1 close to the conveyor 3, a board shell 4 is placed inside the material box 5, a circuit board 52 is placed inside the board shell 4, side holes 15 are opened on both sides of the board shell 4, clamping controllers 20 are installed on both sides of the board shell 4, the clamping controller 20, the end of the clamping controller 20 is electrically connected to the clamping telescopic member 21, the end of the clamping telescopic member 21 is clamped with a clamping strip 22, a proximity sensor 23 is embedded in the middle of the board shell 4, the external bolts on the top of the conveyor 3 are connected to the detection cover 13, one side of the detection cover 13 is bolted to the marking cover 12, and one side of the marking cover 12 is bolted to the paste brush rack 11.

[0068] A material taking and conveying motor group 7 is installed on one side of the top of the outer protective frame 1. The output end of the material taking and conveying motor group 7 passes through the interior of the outer protective frame 1. The external thread of the material taking and conveying motor group 7 is connected with a sliding plate 9. The sliding plate 9 is slidably connected to the top of the outer protective frame 1. A lifting component 10 is installed at the bottom of the sliding plate 9, and a material taking cover 6 is clamped at the bottom of the lifting component 10.

[0069] An infrared sensor 19 is embedded in the top of the material picking cover 6, and material picking controllers 16 are installed on both sides of the material picking cover 6. The end of the material picking controller 16 is electrically connected to the material picking telescopic member 17, and the end of the material picking telescopic member 17 is clamped with a clamping head 18, and the clamping head 18 and the side hole 15 are adapted to each other. A convex point is provided on the top of the middle end of the conveyor 3, and the bottom of the plate shell 4 is clamped with the convex point on the top of the conveyor 3.

[0070] The device is mainly composed of an outer frame 1, a conveyor 3, a main controller 14, a material box 5, a board shell 4, a material feeding and conveying motor group 7, a sliding plate 9, a lifting assembly 10, a material feeding cover 6, a detection cover 13, a marking cover 12, and a paste brushing rack 11. Its purpose is to realize high-precision operations such as automatic material feeding, detection, marking, and solder paste brushing on a circuit board 52. The whole process is carried out under the control of the main control system implanted in the main controller 14.

[0071] The outer protective frame 1 mainly supports and protects the entire device and provides space for installation and operation of other components. The top of the conveyor 3 is a conveyor belt. Through the operation of the conveyor 3, the board shells 4 placed thereon are transported to various operation areas in sequence. The detection cover 13 is used to detect the circuit board 52 to obtain parameters, the components in the marking cover 12 will leave conspicuous marks on the circuit board 52 for easy identification, and the components in the paste brush rack 11 are used to apply glue and fill materials to the circuit board 52.

[0072] A convex point is provided at the top of the middle end of the conveyor 3, and the convex points at the bottom of the plate shell 4 and the top of the conveyor 3 are snap-fitted to ensure the stability of the plate shell 4 during the conveying process and prevent it from shifting. The material box 5 is placed on one side of the outer protective frame 1 close to the conveyor 3 for storing the plate shell 4.

[0073] A circuit board 52 is placed inside the plate shell 4, and side holes 15 are opened on both sides of the plate shell 4. A clamping controller 20, a clamping telescopic member 21 and a clamping strip 22 are installed on both sides of the inside to fix the circuit board 52. A proximity sensor 23 is embedded in the middle to detect whether the circuit board 52 is correctly placed in the plate shell 4, the material taking and conveying motor group 7, the sliding plate 9 and the lifting assembly 10. The material taking and conveying motor group 7 is installed on one side of the top of the outer protective frame 1, and its output end passes through the inside of the outer protective frame 1. The operation of the material taking and conveying motor group 7 can drive the sliding plate 9 to slide at the top of the outer protective frame 1.

[0074] Before processing, the circuit board 52 is placed in the board shell 4. When the circuit board 52 is close to the board shell 4, the internal proximity sensor 23 will quickly sense it. It should be noted that the proximity sensor 23 here has the same principle as the infrared sensor 19. After sensing, the proximity sensor 23 will transmit a signal to the clamping controllers 20 on both sides through the built-in chip, and then the clamping controller 20 will control the front end of the clamping telescopic part 21 to drive the clamping strip 22 to move forward so that it clamps the circuit board 52. A pressure sensor is provided in the clamping strip 22. When the pressure reaches the threshold, a stop signal will be transmitted to the clamping controllers 20 on both sides, and then the clamping controller 20 will control the clamping strip 22 to stop clamping. In this way, the circuit board 52 can be limited, and circuit boards 52 of various specifications can be clamped.

[0075] The lifting assembly 10 is installed at the bottom of the sliding plate 9. The lifting assembly 10 can control the up and down movement of the material collection cover 6. The top of the material collection cover 6 is embedded with an infrared sensor 19 for detecting the position of the plate shell 4. The material collection controller 16, the material collection telescopic member 17 and the clamping head 18 are installed on both sides of the material collection cover 6. The clamping head 18 is adapted to the side holes 15 on both sides of the plate shell 4. When the infrared sensor 19 detects the position of the plate shell 4, the material collection conveying motor group 7 and the lifting assembly 10 work together to move the material collection cover 6 to the top of the plate shell 4, and then the material collection telescopic member extends, and the clamping head 18 is clamped into the side hole 15 to achieve the grabbing of the plate shell 4. Then, the material collection conveying motor group 7 and the lifting assembly 10 work again to take the plate shell 4 out of the material box 5 and place it on the conveyor 3, so that the automatic loading is completed.

[0076] It should be noted that all translational movements in the device are driven by the motor screw structure, while telescoping and lifting are achieved by the cylinder assembly. Specific embodiment 2:

[0078] like Figure 1-17 As shown, according to the content of the specific embodiment one, the following contents are further disclosed: an image transmitter 24 is installed on one side of the detection cover 13, a bracket 25 is bolted to the middle of the top of the detection cover 13, a rotating shaft 26 is movably connected inside the bracket 25, a rotating motor 28 is installed on one side of the bracket 25, an end of the rotating motor 28 is transmission-connected to the rotating shaft 26, a connecting shaft 29 is threadedly connected to the bottom end of the rotating shaft 26, a mounting plate 30 is clamped on the bottom of the connecting shaft 29, a high-definition camera 31 is installed on the bottom of the mounting plate 30, and a first proximity sensor 27 is installed on one side of the top of the detection cover 13.

[0079] In the detection cover 13, the first proximity sensor 27 will sense the position of the plate shell 4 and the circuit board 52. When the plate shell 4 and the circuit board 52 come into the detection cover 13, the built-in transmission chip will transmit signals to the rotary motor 28 and the control end of the high-definition camera 31, and then the rotary motor 28 will drive the rotating shaft 26 to rotate through the output end. The rotation of the rotating shaft 26 will drive the installation plate 30 and the high-definition camera 31 to rotate through the bottom connecting shaft 29. In this device, it only swings slightly, so that the high-definition camera 31 can shoot the circuit board 52 from different angles, improving the accuracy and comprehensiveness of the detection. The image obtained by the high-definition camera 31 will be directly fed back to the image transmitter 24, and then the image transmitter 24 is responsible for transmitting the circuit board image captured by the high-definition camera 31 to the control main system in the main controller 14 in real time. In this way, the control main system can analyze and process the image of the circuit board 52. Specific embodiment three:

[0081] like Figure 1-17As shown, according to the contents of the specific embodiment one, the following contents are further disclosed: a mark control terminal 46 is installed on one side of the top of the mark cover 12, a mark transverse movement control terminal 47 is installed on one side of the mark cover 12, the output end of the mark transverse movement control terminal 47 passes through the interior of the mark cover 12, the output end of the mark transverse movement control terminal 47 is externally threadedly connected to a drive block 51, a longitudinal sliding block 48 is installed at the bottom of the drive block 51, the bottom of the longitudinal sliding block 48 is electrically connected to a telescopic cylinder assembly 49, and a pressure plate 50 is clamped at the bottom of the telescopic cylinder assembly 49.

[0082] A mark 53 is provided on the top of the circuit board 52. The color of the mark 53 is red and the shape of the mark 53 is rectangular. The mark control terminal 46 serves as the core control unit of the entire marking system. It receives instructions from the main controller 14 that controls the main system and coordinates and controls the components in the marking cover 12 according to these instructions. The instructions obtained here are mainly to control the drive assembly to drive the pressure plate 50 to move to the position to be marked, and then press it down on the top surface of the circuit board 52. The mark transverse movement control terminal 47 is responsible for controlling the movement of the marking device in the horizontal direction. After receiving the instruction from the mark control terminal 14, its output terminal starts to move, penetrates the interior of the marking cover, and drives the drive block 51 threadedly connected thereto to move horizontally. In this way, the marking device can mark at different positions of the circuit board 52 to ensure the accuracy and integrity of the marking. Under the action of the mark transverse movement control terminal 47, the drive block 51 moves horizontally along a specific track. A longitudinal sliding block 48 is installed at its bottom to provide support and moving power for the longitudinal sliding block 48. The longitudinal sliding block 48 is responsible for controlling the movement of the marking device in the front and rear positions. It can move forward and backward under the drive of the driving block 51 according to the instructions of the marking control end 46 to adjust the distance between the marking device and the circuit board 52. The telescopic cylinder assembly 49 is connected to the bottom of the longitudinal sliding block 48 and performs telescopic movement through the action of air pressure or hydraulic pressure. Its main function is to control the up and down movement of the pressing plate 50. The bottom of the pressing plate 50 is smeared with erasable ink, the ink is red, and can leave marks at the position where the circuit board needs to be glued. Specific embodiment four:

[0084] like Figure 1-17 As shown, according to the contents of specific embodiment one, the following contents are further disclosed: a stirring drum 33 is installed on one side of the top of the brush paste rack 11, a stirring motor 34 is installed on the top of the stirring drum 33, an observation port 32 is opened on the front of the bottom of the stirring drum 33, and a brush control terminal 35 is installed on the other side of the top of the brush paste rack 11.

[0085] A brush lateral movement control end 36 is installed on one side of the outside of the brush paste rack 11, and the output end of the brush lateral movement control end 36 passes through the inside of the brush paste rack 11. The output end of the brush lateral movement control end 36 is externally threadedly connected to a moving plate 37. The moving plate 37 is slidably connected to the top of the brush paste rack 11, and a longitudinal moving block 38 is installed at the bottom of the moving plate 37. A collector 39 is clamped at the bottom of the longitudinal moving block 38, and a thickness detector 55 is installed on the front of the collector 39. One side of the collector 39 is connected to the mixing drum 33, and a second proximity sensor 42 is embedded on one side of the bottom of the brush paste rack 11.

[0086] A spray pump 54 is installed on one side of the bottom front of the collector 39, and the end flange of the spray pump 54 is connected to a pipeline. The bottom bolts of the collector 39 are connected to a measuring bucket 41, and a metering pump 40 is installed on the top of one side of the measuring bucket 41. A pipeline is connected between one side of the metering pump 40 and the collector 39, and a discharge pipe 44 is provided in the middle of the bottom end of the measuring bucket 41. A scraper 43 is clamped on one side of the bottom of the measuring bucket 41, and a roller plate 45 is clamped on the other side of the bottom of the measuring bucket 41. A roller is installed on the bottom of the roller plate 45, and the bottom heights of the discharge pipe 44, the scraper 43 and the roller plate 45 are flush.

[0087] The first proximity sensor 42 in the paste brush rack 11 is connected to an external recognition camera. When the circuit board 52 reaches the bottom, the first proximity sensor 42 controls the camera to shoot the circuit board 52 after sensing it. The shot image is directly transmitted to the control main system through the brush control terminal 35. The mark scanning system in the control main system uses an image recognition algorithm to detect the position of the mark in the image based on the characteristics of the mark, including specific colors, shapes and patterns. The mark is a specific color, and a color segmentation detection algorithm can be used to locate the mark. The pixels in the image are divided into two categories: mark color and non-mark color. Then, according to the detected mark position, the printing range indicated by the mark is determined. The specific calculation formula is as follows:

[0088] First determine some key parameters:

[0089] A: The area of ​​the marking area, in (mm 2 ), which can be calculated using the position information of the marker in the image and the known relationship between the image resolution and the actual size ratio.

[0090] For example, if the pixel area of ​​the marker in the image is N pixels2 and the image resolution is M pixels / mm, then

[0091]

[0092] H: The required solder paste thickness, in millimeters (mm). This thickness can be determined based on the specific hard brush requirements and circuit board design.

[0093] D: Density of solder paste, in g / mm 2 ), the density of different types of solder paste will be different, which can be obtained by referring to the technical specification of the solder paste.

[0094] Then calculate the volume V of solder paste required:

[0095] The volume formula of solder paste is V = A × i, which is the area of ​​the marked area multiplied by the required solder paste thickness, in mm. 3 .

[0096] Finally, calculate the mass m of solder paste required:

[0097] The mass formula is m=V×D, which is the volume of solder paste multiplied by the density of solder paste, in g.

[0098] In summary, the formula for calculating the amount of solder paste required within the marking range is m=A×H×D.

[0099] At the same time, the gluing control system will control the specific gluing parameters. The specific calculation formula is as follows:

[0100] After the required solder paste amount is calculated according to the formula, the amount and the glue application position information will be transmitted to the brushing control terminal 35. The brushing control terminal 35 will control each group of power sources to drive the brushing equipment to the glue application position to apply glue.

[0101] The paste brush rack 11 is responsible for the solder paste brushing operation on the circuit board in the high-precision solder paste printing device, and is mainly composed of a mixing drum 33, a mixing motor 34, an observation port 32, a brushing control end 35, a brushing lateral control end 36, a moving plate 37, a longitudinal moving block 38, a collector 39, a thickness detector 55, a metering pump 40, a measuring bucket 41, a second proximity sensor 42, a scraper 43, a discharge pipe 44, a roller plate 45 and other components. The mixing drum is used to store solder paste, and the mixing motor 34 is installed at the top of the mixing drum 33. Its function is to drive the mixing device to stir the solder paste to prevent the solder paste from Sedimentation and agglomeration ensure the uniformity of the solder paste. The observation port 32 is opened on the bottom front of the mixing drum 33 to facilitate the operator to observe the status of the solder paste in the mixing drum, such as the remaining amount, fluidity, etc. The brushing control end 35 serves as the core control unit of the brush paste rack 11, receives instructions from the system in the main controller 14, and coordinates and controls the various components in the brush paste rack 11. The brushing parameters can be set, such as the amount of solder paste, brushing speed, thickness requirements, etc. The brushing transverse movement control end 36 is installed on the outside of the brush paste rack 11, and its output end passes through the inside of the brush paste rack 11 and is threadedly connected to the moving plate 37. After receiving the instruction from the brushing control terminal 35, the brushing lateral control terminal 36 controls the movement of the output terminal, driving the movable plate 37 to slide horizontally on the top of the brush paste rack 11. The movable plate 37 provides support for the longitudinal movable block 38 and other components, and adjusts the brushing position by horizontal movement to ensure that different areas of the circuit board 52 can be brushed. The longitudinal movable block 38 is installed at the bottom of the movable plate 37 and can move forward and backward according to the instruction of the brushing control terminal 35. It is connected to the collector 39. By adjusting the height of the collector 39, it can adapt to circuit boards 52 of different thicknesses and different brushing requirements. On the one hand, the collector 39 is connected to the mixing drum 33 to receive the stirred solder paste; on the other hand, the thickness detector 55 installed on the front can detect the thickness of the solder paste brushed on the circuit board 52 in real time, and feed back the information to the brushing control terminal 35.

[0102] The coating control terminal 35 feeds back the thickness data to the defect recognition system in the control main system. The defect recognition system will analyze the detected thickness and determine whether it is uniform according to the thickness. If it is uneven, the specific parameters of the re-coating will be calculated. The detailed calculation formula is as follows:

[0103] Determine key parameters:

[0104] H current : The actual thickness currently detected, in mm

[0105] H target : Target thickness, in mm

[0106] A: The area of ​​the marking area, in mm 2

[0107] D: Density of solder paste, in g / mm 3 .

[0108] Calculate the repainting area;

[0109] First calculate the thickness difference as ΔH:

[0110] ΔH=H target -H current , indicating the thickness that needs to be supplemented.

[0111] Then calculate the recoating volume V supplement :

[0112] V supplement =A×ΔH, that is, the area of ​​the marked area multiplied by the thickness that needs to be supplemented.

[0113] Finally calculate the quality of the repaint:

[0114] The formula for repainting is: m supplement =V supplementt ×D, which is the recoating volume multiplied by the density of solder paste.

[0115] In summary, the calculation formula for repainting parameters is:

[0116] m supplement =A×(H target -H current )×D, where A is the area of ​​the marked area, which determines the size of the repainting range.

[0117] After the required filling parameters are obtained through the formula, they will be transmitted to the brush control end 35, and then the brush control end 35 controls the filling according to the obtained parameters to adjust the brush parameters. The metering pump 40 is installed on the top of one side of the measuring bucket 41 and is connected to the collector 39 through a pipeline. The metering pump 40 accurately controls the amount of solder paste flowing from the collector 39 to the measuring bucket 41 according to the instructions of the brush control end 35. The measuring bucket 41 is used to temporarily store a certain amount of solder paste. A discharge pipe 44 is provided in the middle of the bottom end. By controlling the opening and closing of the discharge pipe 44, the solder paste is evenly output to the circuit board 52. The opening and closing of the discharge pipe 44 is controlled by a solenoid valve. The spray pump 54 is installed on the front side of the bottom of the collector 39 and is connected to the collector 39 through a pipeline. When it is necessary to quickly replenish the solder paste or adjust the solder paste flow rate, the spray pump 54 is started to transport the solder paste from the collector 39 to the measuring bucket 41 or directly to the circuit board 52. The scraper 43 and the roller plate 45 are respectively clamped on both sides of the bottom of the measuring bucket 41, and the bottom heights of the discharge pipe 44, the scraper 43 and the roller plate 45 are aligned. During the brushing process, after the discharge pipe 44 outputs the solder paste, the scraper 43 first scrapes the solder paste flat, and the roller at the bottom of the roller plate 45 then further rolls and flattens the solder paste to ensure that the thickness of the solder paste on the circuit board 52 is uniform. The second proximity sensor 42 is installed on one side of the bottom of the brushing frame 11 to detect whether the board shell 4 enters the brushing area. In summary, under the unified command of the brushing control end 35, the various components in the brushing frame 11 achieve high-precision solder paste brushing on the circuit board 52 through a series of operations such as stirring, lateral movement, longitudinal movement, metering, spraying, scraping and rolling. Specific embodiment five:

[0119] like Figure 1-17 As shown, according to the content of specific embodiment one, the following contents are further disclosed: the control main system includes an identification and marking system, a marking scanning system, a gluing control system and a defect recognition system. In the actual working process, the circuit board 52 is photographed by the high-definition camera 31 in the detection cover 13, and the image is transmitted to the control main system in the main controller 14 through the image transmitter 24. The identification and marking system in the control main system processes the image through the image acquisition module and the image processing module, and then the marking recognition module calculates the gluing range according to the image information, and then transmits the information of the gluing range to the marking control module, and then the marking control module transmits the position information to the marking control terminal 46, and the marking control terminal 46 sends instructions to the driving components in each direction according to the received position information of the required mark, so that the pressure plate 50 is finally covered on the circuit board 52, leaving a mark.

[0120] The specific settings and workflow of the subsystems within the main control system are as follows:

[0121] Sp1. The identification and marking system includes an image acquisition module, an image processing module, a mark recognition module and a mark control module. The high-definition camera 31 takes a picture of the original circuit board and then transmits it to the image acquisition system. The image acquisition system converts the acquired image into a digital graphic signal. When the high-definition camera 31 is aimed at the circuit board, the reflected light from various parts of the circuit board 52 enters the high-definition camera 31 through the lens of the high-definition camera, thereby forming an image that is transmitted to the image acquisition module. The image acquisition module is directly implanted in the high-definition camera 31 and converts the acquired image into a digital image signal. The function of the lens is similar to that of a convex lens. It can converge light so that the light emitted by objects at different positions on the circuit board 52 can form a clear image on the imaging plane of the high-definition camera 31. After the light passes through the lens, an inverted real image is formed on the imaging sensor (such as a CCD or CMOS sensor) of the high-definition camera 31. The imaging sensor is composed of many tiny photosensitive elements. These photosensitive elements can convert the received light signals into electrical signals. Each photosensitive element corresponds to a pixel in the image, and the intensity of the light received determines the size of the output electrical signal. The analog electrical signal output by the imaging sensor is converted into a digital signal through an analog-to-digital converter (ADC). The digital signal is stored in the camera's memory in a specific format or directly transmitted to an external device for processing. In this way, the actual appearance of the circuit board is converted into a digital image signal, in which the value of each pixel represents the brightness or color information of the point.

[0122] Sp2, the image processing module receives the digital graphic signal converted by the image acquisition module. The image preprocessing module preprocesses the acquired image, including denoising and contrast enhancement operations to improve the image quality. The denoising adopts the mean filtering method. The detailed steps are as follows:

[0123] For each pixel in the image, the average value of the pixels in its neighborhood is taken as the new value of the pixel. The size of the neighborhood is usually a square window, and the side length of the window can be adjusted as needed.

[0124] For each pixel in the image, take the average value of the pixel values ​​in its neighborhood as the new value of the pixel. The size of the neighborhood is usually a square window, and the side length of the window can be adjusted as needed. The specific adjustment is as follows: Let the original image be I(x, y), and the image after mean filtering be I mean The size of the (x,y) neighborhood is m×n, then

[0125]

[0126] in

[0127] The values ​​of the m×n pixels around the central pixel I(x,y) are summed and divided by the total number of pixels in the neighborhood mn. The result is used as the new value of the central pixel, which can smooth the image and reduce the impact of random noise.

[0128] Where i and j are the pixel coordinate offsets traversed in the neighborhood.

[0129] Enhance contrast by adjusting the grayscale histogram of the image to make the grayscale distribution of the image more uniform, thereby improving the contrast. Specifically, histogram equalization maps the grayscale range of the original image to a wider grayscale range, making the number of pixels of different grayscale levels in the image closer.

[0130] Assume that the gray level of the original image is r and its probability density function is p r (r), the gray level of the image after histogram equalization is s, then Where w is the integration variable.

[0131] In histogram equalization: It means that the original gray level r is transformed into a new gray level s by integration, so that the gray distribution of the image is more uniform.

[0132] Sp3, the marking control module extracts and analyzes the image processed by the image processing module, performs binarization on the image obtained by edge detection, sets the value of the edge pixel to 1, and the value of the non-edge pixel to 0, and starts from an edge pixel in the image and tracks along the edge pixel until it returns to the starting point to form a closed contour. The contour tracking algorithm uses the eight-neighborhood tracking method. During the tracking process, the pixel coordinates of each contour are recorded, and then the contour area and contour perimeter are calculated:

[0133] Calculate the area of ​​a contour:

[0134] For each extracted contour, its area can be calculated using the following formula:

[0135] Area = ∑ (x,y)∈轮廓 1. Count the number of pixels within the contour.

[0136] Calculate the contour perimeter:

[0137] The perimeter of the contour is obtained by calculating the sum of the distances between adjacent pixels on the contour.

[0138] For adjacent pixels (x1, y1) and (x2, y2), the distance between them can be calculated using the Euclidean distance formula:

[0139] By combining the extracted contour with the size, layout and component position information in the circuit board design file, the range where solder paste needs to be printed is determined, and then the labeler is controlled by the marking control program to label the range where solder paste needs to be printed. After labeling, the range where solder paste needs to be printed will be framed, and the label color is red for easy subsequent identification.

[0140] Sp4. The mark scanning system collects the image of the bottom circuit board, and uses an image recognition algorithm to detect the position of the mark in the image based on the characteristics of the mark, including specific color, shape and pattern. The mark is a specific color, and a color segmentation detection algorithm can be used to locate the mark. The pixels in the image are divided into two categories: mark color and non-mark color. Then, based on the detected mark position, the printing range indicated by the mark is determined, and then the mark range in the image coordinate system is converted into coordinates in the actual printing device coordinate system. The converted coordinate information is sent to the gluing control system. The marked circuit board is easier to identify and less affected by the environment.

[0141] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "comprising a reference structure" do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0142] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An intelligent sensing high-precision solder paste printing device and control system, comprising an outer frame (1), a conveyor (3) and a main controller (14), characterized in that: The main controller (14) is implanted with a control main system. The main controller (14) is installed on one side of the front of the outer protective frame (1). A material box (5) is placed on the inner side of the outer protective frame (1) close to the conveyor (3). A plate shell (4) is placed inside the material box (5). A circuit board (52) is placed inside the plate shell (4). Side holes (15) are provided on both sides of the plate shell (4). A clamping controller (20) is installed on both sides of the plate shell (4). The clamping controller (20) has an end electrically connected to a clamping telescopic member (21). The end of the clamping telescopic member (21) is clamped with a clamping strip (22). A proximity sensor (23) is embedded in the middle of the plate shell (4). The outer top of the conveyor (3) is bolted to a detection cover (13). One side of the detection cover (13) is bolted to a marking cover (12). One side of the marking cover (12) is bolted to a paste brush rack (11).

2. The intelligent sensing high-precision solder paste printing equipment and control system according to claim 1 is characterized in that: A material taking and conveying motor group (7) is installed on one side of the top of the outer protective frame (1), and the output end of the material taking and conveying motor group (7) passes through the interior of the outer protective frame (1). The external thread of the material taking and conveying motor group (7) is connected to a sliding plate (9), and the sliding plate (9) is slidably connected to the top of the outer protective frame (1). A lifting component (10) is installed at the bottom of the sliding plate (9), and a material taking cover (6) is clamped at the bottom of the lifting component (10).

3. The intelligent sensing high-precision solder paste printing equipment and control system according to claim 2 is characterized in that: An infrared sensor (19) is embedded in the top of the material taking cover (6), and material taking controllers (16) are installed on both sides of the material taking cover (6). The end of the material taking controller (16) is electrically connected to a material taking telescopic member (17), and the end of the material taking telescopic member (17) is clamped with a clamping head (18), and the clamping head (18) and the side hole (15) are adapted to each other. A convex point is provided on the top of the middle end of the conveyor (3), and the bottom of the plate shell (4) is clamped with the convex point on the top of the conveyor (3).

4. The intelligent sensing high-precision solder paste printing equipment and control system according to claim 1 is characterized in that: An image transmitter (24) is installed on one side of the detection cover (13); a bracket (25) is bolted to the middle of the top of the detection cover (13); a rotating shaft (26) is movably connected to the inside of the bracket (25); a rotary motor (28) is installed on one side of the bracket (25); an end of the rotary motor (28) is transmission-connected to the rotating shaft (26); a connecting shaft (29) is threadedly connected to the bottom end of the rotating shaft (26); a mounting plate (30) is clamped to the bottom end of the connecting shaft (29); a high-definition camera (31) is installed on the bottom of the mounting plate (30); and a first proximity sensor (27) is installed on one side of the top of the detection cover (13).

5. The intelligent sensing high-precision solder paste printing equipment and control system according to claim 1 is characterized in that: A marking control end (46) is installed on one side of the top of the marking cover (12), and a marking transverse movement control end (47) is installed on one side of the marking cover (12). The output end of the marking transverse movement control end (47) passes through the interior of the marking cover (12), and the output end of the marking transverse movement control end (47) is externally threadedly connected to a driving block (51). A longitudinal sliding block (48) is installed at the bottom of the driving block (51), and the bottom of the longitudinal sliding block (48) is electrically connected to a telescopic cylinder assembly (49), and a pressure plate (50) is clamped at the bottom of the telescopic cylinder assembly (49).

6. The intelligent sensing high-precision solder paste printing equipment and control system according to claim 1 is characterized in that: A mark (53) is provided on the top of the circuit board (52); the color of the mark (53) is red, and the shape of the mark (53) is rectangular.

7. The intelligent sensing high-precision solder paste printing equipment and control system according to claim 1 is characterized in that: A stirring drum (33) is installed on one side of the top of the paste brush rack (11), a stirring motor (34) is installed on the top of the stirring drum (33), an observation port (32) is provided on the front of the bottom of the stirring drum (33), and a brush control terminal (35) is installed on the other side of the top of the paste brush rack (11).

8. The intelligent sensing high-precision solder paste printing equipment and control system according to claim 7 is characterized in that: A brush lateral movement control end (36) is installed on one side of the outside of the brush paste rack (11), and the output end of the brush lateral movement control end (36) passes through the inside of the brush paste rack (11). The output end of the brush lateral movement control end (36) is externally threadedly connected to a moving plate (37), and the moving plate (37) is slidably connected to the top of the brush paste rack (11). A longitudinal moving block (38) is installed at the bottom of the moving plate (37), and a collector (39) is clamped at the bottom of the longitudinal moving block (38). A thickness detector (55) is installed on the front of the collector (39), and one side of the collector (39) is connected to the mixing drum (33). A second proximity sensor (42) is embedded on one side of the bottom of the brush paste rack (11).

9. The intelligent sensing high-precision solder paste printing equipment and control system according to claim 8, characterized in that: A spray pump (54) is installed on one side of the front bottom of the collector (39), and a pipeline is connected to the end flange of the spray pump (54). A measuring bucket (41) is bolted to the bottom of the collector (39), and a metering pump (40) is installed on the top of one side of the measuring bucket (41). A pipeline is connected between one side of the metering pump (40) and the collector (39). A discharge pipe (44) is provided in the middle of the bottom end of the measuring bucket (41). A scraper (43) is clamped on one side of the bottom of the measuring bucket (41), and a roller plate (45) is clamped on the other side of the bottom of the measuring bucket (41). A roller is installed at the bottom of the roller plate (45), and the bottoms of the discharge pipe (44), the scraper (43) and the roller plate (45) are flush with each other.

10. The system according to any one of claims 1 to 9, wherein: The main control system includes a recognition and marking system, a marking scanning system, a gluing control system and a defect recognition system. The specific settings and workflow of the subsystems in the main control system are as follows: Sp1, the identification marking system includes an image acquisition module, an image processing module, a mark recognition module and a mark control module. The high-definition camera (31) takes a picture of the original circuit board and then transmits it to the image acquisition system. The image acquisition system converts the acquired image into a digital graphic signal. Sp2, the image processing module receives the digital graphic signal converted by the image acquisition module. The image preprocessing module preprocesses the acquired image, including denoising and contrast enhancement operations, to improve the image quality. The denoising adopts a mean filtering method. The detailed steps are as follows: For each pixel in the image, take the average value of the pixel values ​​in its neighborhood as the new value of the pixel. The size of the neighborhood is usually a square window, and the side length of the window can be adjusted as needed, as follows: ， ； For the center pixel Around The values ​​of the pixels are summed and then divided by the total number of pixels in the neighborhood. The result is used as the new value of the central pixel, which can smooth the image and reduce the impact of random noise; in ; Enhance the contrast by adjusting the grayscale histogram of the image through histogram equalization to make the grayscale distribution of the image more uniform, thereby improving the contrast. The specific adjustment formula is as follows: Assume the grayscale of the original image is , and its probability density function is , the gray level of the image after histogram equalization is , ,in Time-integrated variable; In histogram equalization: It means that the original gray level r is transformed into a new gray level s by integration, so that the gray distribution of the image is more uniform; Sp3, the marking control module extracts and analyzes the image processed by the image processing module, performs binarization on the image obtained by edge detection, sets the value of the edge pixel to 1, and the value of the non-edge pixel to 0, and starts from an edge pixel in the image and tracks along the edge pixel until it returns to the starting point to form a closed contour. The contour tracking algorithm uses the eight-neighborhood tracking method. During the tracking process, the pixel coordinates of each contour are recorded, and then the contour area and contour perimeter are calculated: Calculate the area of ​​a contour: For each extracted contour, its area can be calculated using the following formula: Area = ,Count the number of pixels within the contour; Calculate the contour perimeter: The perimeter of the contour is obtained by calculating the sum of the distances between adjacent pixels on the contour; For adjacent pixels , the distance between them can be calculated using the Euclidean distance formula: The range where solder paste needs to be printed is determined by combining the extracted contour with the size, layout and component position information in the circuit board design file. Then, the labeler is controlled by the marking control program to label the range where solder paste needs to be printed. After labeling, the range where solder paste needs to be printed will be framed. The labeling color is red for easy subsequent identification. Sp4. The mark scanning system collects the image of the bottom circuit board, and uses an image recognition algorithm to detect the position of the mark in the image based on the characteristics of the mark, including specific color, shape and pattern. The mark is a specific color, and a color segmentation detection algorithm can be used to locate the mark. The pixels in the image are divided into two categories: mark color and non-mark color. Then, based on the detected mark position, the printing range indicated by the mark is determined, and then the mark range in the image coordinate system is converted into coordinates in the actual printing device coordinate system. The converted coordinate information is sent to the gluing control system. The marked circuit board is easier to identify and less affected by the environment.

Images