Screen inkjet device based on image processing

Abstract

The present invention relates to the field of inkjet device detection and positioning technology, in particular to a screen inkjet device based on image processing, comprising a conveying platform and an alignment component, a cleaning component, an inkjet component, a curing component and an automatic optical detection component sequentially arranged along the conveying direction of the conveying platform; the conveying platform comprises a tray for carrying a display screen, and the alignment component and the tray together form a mounting position for positioning the display screen; an image positioning component is installed on one side of the inkjet component, and the image positioning component is connected to the conveying platform. The present invention performs double positioning processing on the display screen through the alignment component and the image positioning component before inkjet printing, and automatically detects the inkjet effect and foreign matter contamination of the display screen through the automatic optical detection component after inkjet printing, thereby improving the inkjet efficiency and inkjet accuracy while realizing automatic detection.

Description

Technical Field

[0001] The present invention relates to the technical field of inkjet device detection and positioning, and in particular to a screen inkjet device based on image processing. Background Art

[0002] As electronic devices are increasingly used, the demand for display screens is also increasing. The corresponding display screens are also constantly being updated. The demand for shading ink spraying on the four edges of the screen is also increasing, and the demand for its process accuracy, production efficiency, and good product detection is also constantly improving. To ensure the quality of production, it is necessary to inspect the products that have been sprayed with shading ink on the four edges of the screen. At present, manual inspection is generally used, which is time-consuming and has a high false detection rate, affecting production efficiency. Summary of the invention

[0003] The present invention provides a screen inkjet device based on image processing, which solves the technical problems of low inkjet efficiency, low inkjet precision, low detection efficiency and the like of the display screen.

[0004] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is to provide a screen inkjet device based on image processing, including a conveying platform and an alignment component, a cleaning component, an inkjet component, a curing component and an automatic optical detection component arranged in sequence along the conveying direction of the conveying platform; the conveying platform includes a tray for carrying a display screen, and the alignment component and the tray together form an installation position for positioning the display screen; an image positioning component is installed on one side of the inkjet component, and the image positioning component includes a positioning camera and a first image acquisition and analysis module, the signal output end of the positioning camera is connected to the first image acquisition and analysis module, and the signal output end of the first image acquisition and analysis module is connected to the conveying platform; the automatic optical detection component is used to detect the inkjet effect and foreign matter contamination of the display screen.

[0005] Furthermore, the conveying platform also includes a Y-axis linear motor module, a first dust-free drag chain and a rotating base, and the rotating base is drivingly connected to the tray to drive the tray to rotate; the Y-axis linear motor module includes a linear guide and a servo motor, the rotating base is slidably installed on the linear guide, the servo motor is drivingly connected to the first dust-free drag chain, and the upper end of the first dust-free chain is connected to the rotating base.

[0006] Furthermore, the alignment assembly includes an X-axis screw module, a first alignment cylinder, a first alignment block, a second alignment cylinder, an alignment plate, a second alignment block, a third alignment cylinder and a third alignment block. The X-axis screw module is drivingly connected to the first alignment cylinder to drive the first alignment cylinder to move, the output end of the first alignment cylinder is connected to the first alignment block, the output end of the second alignment cylinder is connected to the alignment plate, the second alignment block and the third alignment cylinder are arranged side by side on the alignment plate, and the output end of the third alignment cylinder is connected to the third alignment block.

[0007] Furthermore, the cleaning component is a plasma cleaner, and gas recovery devices are arranged on both sides below the cleaning component.

[0008] Furthermore, the inkjet assembly includes a first double-motor X-axis linear motor module, an inkjet unit, a second dust-free drag chain, a Z-axis screw module, a third dust-free drag chain, a first adapter plate and a second adapter plate; the first double-motor X-axis linear motor module is drive-connected to the first adapter plate, and one end of the second dust-free drag chain is connected to the first adapter plate; the Z-axis screw module is installed on the first adapter plate, the Z-axis screw module is drive-connected to the second adapter plate, and one end of the third dust-free drag chain is connected to the second adapter plate; the inkjet unit is installed on the second adapter plate.

[0009] Furthermore, the inkjet unit includes a direct drive motor, a nozzle, a nozzle board, an ink cartridge, a pressure gauge, a pressure regulating valve, a vacuum generator, a gas tank and a proportional valve; the direct drive motor is connected to the nozzle drive to drive the nozzle to rotate; the proportional valve, the vacuum generator, the gas tank, the pressure regulating valve, the pressure gauge and the ink cartridge are connected in series in sequence, and the ink cartridge is connected to the nozzle through the nozzle board.

[0010] Furthermore, there are two positioning cameras, namely the first positioning camera and the second positioning camera; the first positioning camera and the second positioning camera are respectively moved to the set reference photographing positions, and after taking pictures, the images are transmitted to the first image acquisition and analysis module for processing and analysis; the first image acquisition and analysis module establishes a mapping relationship between camera pixel coordinates and axis coordinates, and converts the offset of pixels matching the image features after the first positioning camera and the second positioning camera take pictures into an axis coordinate offset through the mapping relationship; the conveying platform is corrected according to the axis coordinate offset to enable the inkjet assembly to align with the path where the display screen needs to spray ink for inkjet.

[0011] Furthermore, it also includes a nozzle wiping assembly, which includes a speed regulating motor, an unwinding shaft, a reeling shaft, a tension roller, a wiping cloth sensor and a wiping cloth, wherein the speed regulating motor is drivingly connected to the unwinding shaft; the reel formed by winding the wiping cloth is sleeved on the unwinding shaft and connected to the reeling shaft through the tension roller, and the wiping cloth sensor is arranged on one side of the tension roller.

[0012] Furthermore, the curing assembly includes a second double-motor X-axis linear motor module, a fourth dust-free drag chain, a manual fine-tuning unit, a curing lamp and a third adapter plate, the second double-motor X-axis linear motor module is drive-connected to the third adapter plate, and one end of the fourth dust-free drag chain is connected to the third adapter plate; the curing light is installed on the third adapter plate through the manual fine-tuning unit.

[0013] Furthermore, the automatic optical inspection component includes a line scan camera, a strip coaxial light and a second image acquisition and analysis module. The signal output end of the line scan camera is connected to the second image acquisition and analysis module, and the signal output end of the second image acquisition and analysis module is connected to the inkjet component; the second image acquisition and analysis module performs frequency domain filtering on the image, divides the display screen into ink area and non-ink area, and performs defect analysis on noise points in the ink area and non-ink area.

[0014] The beneficial effects of the present invention are:

[0015] In the above-mentioned screen inkjet device based on image processing, when the display screen is loaded, the alignment component and the tray together form a mounting position for positioning the display screen, thereby improving the initial positioning accuracy; before inkjet, the display screen is photographed and image processed by the image positioning component, the position of the display screen is analyzed, and the position correction is achieved by fine-tuning the conveying platform; after the inkjet is completed, the inkjet effect and foreign matter contamination of the display screen are automatically detected by the automatic optical detection component. While realizing automatic detection, the present invention improves the inkjet efficiency and inkjet accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the structure of a screen inkjet device based on image processing.

[0017] Figure 2 It is a structural schematic diagram of the conveying platform.

[0018] Figure 3 It is a schematic diagram of the state in which the alignment component positions the display screen.

[0019] Figure 4 It is a schematic diagram of the structure of the cleaning component.

[0020] Figure 5It is a schematic diagram of the structure of the inkjet assembly.

[0021] Figure 6 It is a structural schematic diagram of an inkjet unit.

[0022] Figure 7 It is a schematic diagram of the structure of the nozzle wiping assembly.

[0023] Figure 8 It is a schematic diagram of the structure of the curing component.

[0024] Fig. 9 It is a schematic diagram of the structure of an automatic optical inspection component.

[0025] Description of the accompanying drawings: display screen 1, ink supply assembly 10, conveying platform 20, Y-axis linear motor module 21, first dust-free drag chain 22, rotating base 23, tray 24, vacuum suction cup 25, alignment assembly 30, X-axis screw module 31, first alignment cylinder 32, first alignment block 33, second alignment cylinder 34, alignment plate 35, second alignment block 36, third alignment cylinder 37, third alignment block 38, cleaning assembly 40, gas recovery device 41, inkjet assembly 50, first double-acting X-axis linear motor module 51, inkjet unit 52, direct drive motor 521, nozzle 522, nozzle board 523, ink cartridge 524, pressure gauge 525, pressure regulator Valve 526, vacuum generator 527, air storage tank 528, proportional valve 529, second dust-free drag chain 53, Z-axis screw module 54, third dust-free drag chain 55, first adapter plate 56, second adapter plate 57, nozzle wiping assembly 60, speed regulating motor 61, unwinding shaft 62, rewinding shaft 63, tension roller 64, wiping cloth sensor 65, wiping cloth 66, curing assembly 70, second double-motor X-axis linear motor module 71, fourth dust-free drag chain 72, manual fine-tuning unit 73, curing lamp 74, third adapter plate 75, automatic optical detection assembly 80, line scan camera 81, telecentric lens 82, strip coaxial light 83, adjustment micrometer head 84, image positioning assembly 90. DETAILED DESCRIPTION

[0026] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. 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.

[0027] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0028] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, an integral connection, a mechanical connection, an electrical connection, a direct connection, an indirect connection through an intermediate medium, or the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] See also Figure 1 As shown, the present invention relates to a screen inkjet device based on image processing, comprising a frame, an ink supply assembly 10 and a conveying platform 20 installed on the frame, an alignment assembly 30, a cleaning assembly 40, an inkjet assembly 50, a curing assembly 70 and an automatic optical detection assembly 80 arranged in sequence along the conveying direction of the conveying platform 20, the ink supply assembly 10 is connected to the inkjet assembly 50, and the conveying platform 20 can convey the display screen 1 from one station to the next station. The alignment assembly 30 and the tray 24 of the conveying platform 20 together form an installation position for positioning the display screen 1, so as to realize the manual loading alignment of the product. An image positioning assembly 90 is installed on one side of the inkjet assembly 50, and the image positioning assembly 90 includes a positioning camera and a first image acquisition and analysis module, the signal output end of the positioning camera is connected to the first image acquisition and analysis module, and the signal output end of the first image acquisition and analysis module is connected to the inkjet assembly 50. Before inkjetting, the display screen 1 is photographed and image processed by the image positioning assembly 90, the position of the display screen 1 is analyzed, and the position correction is realized by fine-tuning the conveying platform 20. The display screen 1 after inkjet is transported to the automatic optical detection component 80 via the transport platform 20 , and the automatic optical detection component 80 automatically detects the inkjet effect and foreign matter contamination of the display screen.

[0030] like Figure 2As shown, the conveying platform 20 includes a Y-axis linear motor module 21, a first dust-free drag chain 22, a rotating base 23 and a tray 24. A plurality of vacuum suction cups 25 are embedded on the surface of the tray 24, and the vacuum suction cups 25 are connected to a vacuum machine. The display screen 1 is adsorbed and fixed on the tray 24 through the vacuum suction cups 25, thereby preventing the display screen 1 from being displaced during the conveying process. The rotating base 23 is driven and connected to the tray 24 to drive the tray 24 to rotate, so as to realize a 90-degree rotation of the display screen 1, thereby realizing inkjet processing on the four sides of the screen. The Y-axis linear motor module 21 includes a linear guide and a servo motor, and the rotating base 23 is slidably mounted on the linear guide. The servo motor is driven and connected to the first dust-free drag chain 22, and the upper end of the first dust-free chain is connected to the rotating base 23. The Y-axis linear motor module 21 drives the first dust-free drag chain 22 to move through the servo motor, and the first dust-free drag chain 22 drives the rotating base 23 to move on the linear guide, thereby allowing the tray 24 to move in the Y-axis direction.

[0031] A direct drive motor is installed inside the rotating base 23 to realize a high-precision rotation function. After the image positioning assembly 90 calibrates the display screen, the rotating base rotates to make the edges of the display screen parallel.

[0032] Combination Figure 3 As shown, the alignment assembly 30 includes an X-axis screw module 31, a first alignment cylinder 32, a first alignment block 33, a second alignment cylinder 34, an alignment plate 35, a plurality of second alignment blocks 36, a third alignment cylinder 37 and a third alignment block 38. The X-axis screw module 31 is drivingly connected to the first alignment cylinder 32 to drive the first alignment cylinder 32 to move along the X-axis direction. The output end of the first alignment cylinder 32 is connected to the first alignment block 33. The angle position of the first alignment block 33 is adjusted by the first alignment cylinder 32 so that the first alignment block 33 abuts against the side of the display screen 1 parallel to the X-axis. The first alignment cylinder 32 is driven by the X-axis screw module 31 to adjust the position of the first alignment block 33 corresponding to the tray 24, so as to realize the positioning of display screens 1 of different sizes, and can adapt to display screens of 17-32 inches. The output end of the second alignment cylinder 34 is connected to the alignment plate 35, and a plurality of second alignment blocks 36 are arranged side by side on the alignment plate 35. The position of the second alignment block 36 is adjusted by the second alignment cylinder 34 so that it forms a 90-degree angle with the first alignment block 33, so that the second alignment block 36 abuts against the side of the display screen 1 parallel to the Y axis. The third alignment cylinder 37 is arranged side by side with the second alignment block 36 on the alignment plate 35, and the output end of the third alignment cylinder 37 is connected to the third alignment block 38. The position of the third alignment block 38 is adjusted by the third alignment cylinder 37 so that it is in the same straight line with the first alignment block 33, and the third alignment block 38 abuts against the side of the display screen 1 parallel to the X axis. The third alignment block 38 and the adjacent second alignment block 36 form an angular positioning of the display screen 1.

[0033] like Figure 4 As shown, the cleaning component 40 is a plasma cleaner, which sprays plasma gas to remove static electricity, stains, particles, dust and other substances from the inkjet surface of the display screen, thereby improving the inkjet quality. A gas recovery device 41 is arranged on both sides below the cleaning component 40, and the gas recovery device 41 can recover the overflowed ozone and nitrogen, etc., and connect to the organic exhaust system for exhaust.

[0034] like Figure 5 As shown, the inkjet assembly 50 includes a first double-motor X-axis linear motor module 51, two inkjet units 52, two second dust-free drag chains 53, two Z-axis screw modules 54, two third dust-free drag chains 55, two first adapter plates 56 and two second adapter plates 57; the two first adapter plates 56 are symmetrically arranged on the first double-motor X-axis linear motor module 51, the first double-motor X-axis linear motor module 51 is drivingly connected to the first adapter plate 56, and one end of the second dust-free drag chain 53 is connected to the first adapter plate 56; the Z-axis screw module 54 is installed on the first adapter plate 56, the Z-axis screw module 54 is drivingly connected to the second adapter plate 57, and one end of the third dust-free drag chain 55 is connected to the second adapter plate 57; combined Figure 6 As shown, the inkjet unit 52 and the image positioning assembly 90 are installed on the second adapter plate 57. The inkjet unit 52 is driven to move in the X-axis direction by the first double-actuator X-axis linear motor module 51, and the Z-axis screw module 54 drives the inkjet unit 52 to move in the Z-axis direction. By equipping two sets of inkjet units 52, the two heads can spray ink at the same time, which effectively improves the efficiency of inkjet.

[0035] The inkjet unit 52 includes a direct drive motor 521, a nozzle 522, a nozzle board 523, an ink cartridge 524, a pressure gauge 525, a pressure regulating valve 526, a vacuum generator 527, an air tank 528, and a proportional valve 529; the direct drive motor 521 is connected to the nozzle 522 to drive the nozzle 522 to rotate, and the direct drive motor 521 can precisely control the angle of the nozzle 522 to improve the inkjet accuracy. The proportional valve 529, the vacuum generator 527, the air tank 528, the pressure regulating valve 526, the pressure gauge 525, and the ink cartridge 524 are connected in series in sequence, and the vacuum generator 527 is connected to an air source. After the gas of the air source passes through the vacuum generator 527, the vacuum generator 527 is regulated by the proportional valve 529 to generate negative pressure, and enters the air tank 528 to provide a stable negative pressure. After the negative pressure is controlled by the pressure regulating valve 526, it enters the ink cartridge 524, and then the ink in the ink cartridge 524 enters the nozzle 522 at a constant negative pressure value. The ink cartridge 524 is provided with an ink monitoring sensor for detecting the amount of ink. When the amount of ink is too low, the ink supply assembly supplies ink to the ink cartridge 524. The ink cartridge 524 is connected to the nozzle 522 through the nozzle board 523, and the ink is sprayed onto the screen of the display screen 1 by controlling the nozzle board 523 to control the nozzle 522 group.

[0036] In this embodiment, all driving devices use precision screws or linear motors to ensure inkjet accuracy; the inkjet X-axis uses a double-actuator linear motor module, the inkjet Y-axis uses a precision marble linear motor module, the inkjet Z-axis uses a standard screw module, and the drag chain uses a dust-free drag chain. The entire equipment uses standard modules, and the standardized module design makes the equipment simple and stable.

[0037] A nozzle wiping assembly 60 is also provided on one side of the nozzle 522 to prevent the nozzle from being blocked and affecting the inkjet quality. Figure 7 As shown, the nozzle wiping assembly 60 includes a speed regulating motor 61, an unwinding shaft 62, a reeling shaft 63, a tension roller 64, a wiping cloth sensor 65 and a wiping cloth 66. The speed regulating motor 61 is connected to the unwinding shaft 62 by driving; the reel formed by the wiping cloth 66 is sleeved on the unwinding shaft 62 and connected to the reeling shaft 63 through the tension roller 64, and the wiping cloth sensor 65 is arranged on one side of the tension roller 64. The receiving and unwinding of the wiping cloth 66 is controlled by the speed regulating motor 61, and the use of the wiping cloth 66 can be monitored at any time through the wiping cloth sensor 65. A tension roller 64 is arranged between the unwinding shaft 62 and the reeling shaft 63, which can change the tension of the wiping cloth 66 to prevent the wiping cloth 66 from loosening on the one hand, and prevent damage to the nozzle 522 on the other hand.

[0038] The image positioning component 90 is arranged on one side of the nozzle 522. There are two positioning cameras, namely the first positioning camera and the second positioning camera. The first positioning camera and the second positioning camera are respectively installed on one side of the two nozzles. The first positioning camera and the second positioning camera are respectively moved to the set reference shooting position, and after taking pictures, the images are respectively transmitted to the first image acquisition and analysis module for processing and analysis; the first image acquisition and analysis module establishes a mapping relationship between the camera pixel coordinates and the axis coordinates, and converts the offset of the pixels matching the image features after the first positioning camera and the second positioning camera take pictures into the axis coordinate offset through the mapping relationship; the conveying platform 20 is corrected according to the axis coordinate offset so that the nozzle 522 is aligned with the path where the display screen 1 needs to spray ink for inkjet.

[0039] A mark is made on the conveying platform 20 for associating the coordinate systems of the two positioning cameras (ie, mapping the X-axis coordinate of the second positioning camera to the X-axis of the first positioning camera). This can greatly improve the angle correction accuracy of the display screen 1, thereby ensuring the straightness of the inkjet.

[0040] The role of the marker is to establish a mapping relationship between the camera pixel coordinates and the axis coordinates. Through the mapping relationship, the pixel offset of the image feature matching after the first positioning camera and the second positioning camera take pictures can be converted into an axis coordinate offset. Specifically, the positioning camera can move in the X-axis direction, and the conveying platform 20 moves in the Y-axis direction. Place a display screen on the conveying platform 20, move the marker to the field of view of the positioning camera, click the positioning camera to take pictures, and then generate a template by selecting the marked area and perform template matching (template matching is to find the area most similar to the template image in an image), and set the matching pixel coordinates, the positioning camera X-axis and the conveying platform Y-axis coordinates as the benchmark. The positioning camera and the conveying platform 20 move 9 positions together, and after each movement is completed, the photo matching is performed, and the pixel coordinates of the marker are recorded, and the coordinate positions of the positioning camera X-axis and the platform Y-axis are recorded at the same time. Through 9 groups of pixel coordinates and 9 groups of axis coordinates, a calibration matrix can be generated, and any pixel coordinate of the image after the positioning camera takes pictures can be calculated by the matrix to obtain the corresponding axis coordinates. By calculating the difference between the pixel coordinates of the image feature matching after the first positioning camera and the second positioning camera take pictures and the reference position, corresponding position compensation can be performed to ensure that the position of each inkjet is consistent.

[0041] The coordinates of the two positioning cameras are associated, the real-time image of the first positioning camera is opened, the first positioning camera is moved to the feature point in the X-axis direction, and the conveying platform 20 is adjusted to make the center of the image of the first positioning camera coincide with the center of the feature point in the Y-axis direction, and the X-axis coordinate position X1 is recorded at this time; the second positioning camera is operated in the same way as the first positioning camera, and the X-axis coordinate X2 of the second positioning camera is recorded; through the relationship between X1 and X2, the coordinates of the second positioning camera can be converted to the coordinates of the first positioning camera during positioning; at this time, X21 is the coordinate of the second positioning camera when taking pictures on the X-axis.

[0042] Through the associated mapping relationship between the two positioning cameras, the axis coordinates converted by the first positioning camera are converted into the axis coordinates of the second positioning camera; the two points are connected into a straight line, the angle difference with the reference straight line is calculated, the conveying platform 20 is rotated, and the angle correction is performed according to the angle difference.

[0043] After completing the angle correction, take photos again and perform template matching. The obtained pixel coordinates are converted into axis coordinates. At this time, after calculating the current XY deviation and the reference XY deviation, the corresponding axis is compensated for the position, and the positioning process is completed.

[0044] like Figure 8As shown, the curing assembly 70 includes a second double-acting X-axis linear motor module 71, two fourth dust-free drag chains 72, two manual fine-tuning units 73, two curing lamps 74 and two third adapter plates 75. The second double-acting X-axis linear motor module 71 is connected to the third adapter plate 75 by driving, and one end of the fourth dust-free drag chain 72 is connected to the third adapter plate 75; the curing lamp 74 is installed on the third adapter plate 75 through the manual fine-tuning unit 73. After the equipment is running, the curing lamp 74 will stop at the curing position in advance, waiting for the inkjet to be completed, and can be cured directly. And the two curing lamps 74 are cured at the same time, so that the double heads are cured at the same time, which effectively improves the curing efficiency.

[0045] like Fig. 9 As shown, the automatic optical detection component 80 includes two line scan cameras 81, two telecentric lenses 82, strip coaxial lights 83, two adjustment differential heads 84 and a second image acquisition and analysis module. The strip coaxial lights 83 are arranged below the display screen 1 to provide supplementary light for the display screen 1. The line scan camera 81 is arranged above the display screen 1, and the telecentric lens 82 is used in conjunction with the line scan camera 81. The telecentric lens 82 is used to collect the inkjet effect image placed on the display screen. The line scan camera 81 is connected to the adjustment differential head 84, which is used to precisely adjust the up and down directions, front and back directions and rotation directions to ensure that the two sets of line scan cameras 81 are on the same surface, and finally multiple high-definition pictures are spliced ​​to form a whole photo. The signal output end of the line scan camera 81 is connected to the second image acquisition and analysis module, and the signal output end of the second image acquisition and analysis module is connected to a reminder device, such as a player, a display and other equipment to output the detection results. The automatic optical detection component 80 can not only detect the inkjet effect of the display screen 1, but also detect the foreign matter contamination on the display screen 1.

[0046] The second image acquisition and analysis module performs frequency domain filtering on the image of the line scan camera 81. The edge of the background usually has obvious grayscale differences, that is, the parts with high frequency of change, and the display screen 1 is divided into an ink area and a non-ink area. The same is true for noise points, because the grayscale difference between the noise points and the background is obvious. On the contrary, the grayscale changes slowly, and it is a continuous gradient area, which is the low frequency. The low-frequency part of the background is filtered out, and the high-frequency part left is the noise point, and combined with morphology, the characteristic difference between the defect and the background is further highlighted. Finally, according to the location, area, length, and severity of the defect, dirt, bumps, leaks, ink splashing, etc. are found.

[0047] According to the ink area and non-ink area, the edge is found by vertically picking points on both sides of the ink area. After the edge is found successfully, the distance between the two points is calculated to get the size of the ink area, and the card control is performed in combination with the set parameters. In addition, the sampling density of the points can be set according to actual needs.

[0048] In the above-mentioned screen inkjet device based on image processing, while ensuring the inkjet accuracy, the inkjet efficiency is improved, and it is compatible with 17-32 inch products. It can also reduce manpower and avoid the influence of objective factors brought by manual inspection.

[0049] The overall workflow of the present application is as follows: first, manually load the material, and then accurately place the display screen 1 on the tray 24 of the conveying platform 20 through the positioning component 30; the Y-axis linear motor module 21 of the conveying platform 20 moves the tray 24 to the cleaning component 40 for cleaning; then it moves to the inkjet component 50, and after the image positioning component 90 performs positioning, the inkjet component 50 starts to spray ink; after spraying, it moves to the curing component 70 for curing, and then the platform rotates 90°, and inkjet and cure the adjacent sides of the display screen 1; after the four sides of the display screen 1 are inkjet-cured, it finally moves to the automatic optical detection component 80 for detection, and the detection results will be classified by manual material collection.

[0050] The above implementation modes are merely descriptions of the preferred implementation modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary engineering and technical personnel in the field shall fall within the protection scope determined by the claims of the present invention.

Claims

1. A screen inkjet device based on image processing, characterized in that: It comprises a conveying platform and an alignment component, a cleaning component, an inkjet component, a curing component and an automatic optical detection component which are sequentially arranged along the conveying direction of the conveying platform; the conveying platform comprises a tray for carrying a display screen, and the alignment component and the tray together form a mounting position for positioning the display screen; an image positioning component is installed on one side of the inkjet component, and the image positioning component comprises a positioning camera and a first image acquisition and analysis module, the signal output end of the positioning camera is connected to the first image acquisition and analysis module, and the signal output end of the first image acquisition and analysis module is connected to the conveying platform; the automatic optical detection component is used to detect the inkjet effect and foreign matter contamination of the display screen; The alignment assembly includes an X-axis screw module, a first alignment cylinder, a first alignment block, a second alignment cylinder, an alignment plate, a second alignment block, a third alignment cylinder and a third alignment block, the X-axis screw module is drivingly connected to the first alignment cylinder to drive the first alignment cylinder to move, the output end of the first alignment cylinder is connected to the first alignment block, the output end of the second alignment cylinder is connected to the alignment plate, the second alignment block and the third alignment cylinder are arranged side by side on the alignment plate, and the output end of the third alignment cylinder is connected to the third alignment block; There are two positioning cameras, namely a first positioning camera and a second positioning camera; the first positioning camera and the second positioning camera are respectively moved to the set reference photographing positions, and after taking photos, the images are transmitted to the first image acquisition and analysis module for processing and analysis; The first image acquisition and analysis module establishes a mapping relationship between camera pixel coordinates and axis coordinates, and converts the offset of pixels of image feature matching after the first positioning camera and the second positioning camera take photos into an axis coordinate offset through the mapping relationship; The conveying platform is calibrated according to the axis coordinate offset so that the inkjet assembly is aligned with the path where the display screen needs to spray ink to spray ink.

2. The screen inkjet device based on image processing according to claim 1, characterized in that: The conveying platform also includes a Y-axis linear motor module, a first dust-free drag chain and a rotating base, and the rotating base is driven and connected to the tray to drive the tray to rotate; the Y-axis linear motor module includes a linear guide and a servo motor, the rotating base is slidably installed on the linear guide, the servo motor is driven and connected to the first dust-free drag chain, and the upper end of the first dust-free drag chain is connected to the rotating base.

3. The screen inkjet device based on image processing according to claim 1, characterized in that: The cleaning component is a plasma cleaner, and gas recovery devices are arranged on both sides below the cleaning component.

4. The screen inkjet device based on image processing according to claim 1, characterized in that: The inkjet assembly includes a first double-motor X-axis linear motor module, an inkjet unit, a second dust-free drag chain, a Z-axis screw module, a third dust-free drag chain, a first adapter plate and a second adapter plate; the first double-motor X-axis linear motor module is drivingly connected to the first adapter plate, and one end of the second dust-free drag chain is connected to the first adapter plate; the Z-axis screw module is installed on the first adapter plate, the Z-axis screw module is drivingly connected to the second adapter plate, and one end of the third dust-free drag chain is connected to the second adapter plate; the inkjet unit is installed on the second adapter plate.

5. The screen inkjet device based on image processing according to claim 4, characterized in that: The inkjet unit includes a direct drive motor, a nozzle, a nozzle board, an ink cartridge, a pressure gauge, a pressure regulating valve, a vacuum generator, a gas tank and a proportional valve; the direct drive motor is connected to the nozzle drive to drive the nozzle to rotate; the proportional valve, the vacuum generator, the gas tank, the pressure regulating valve, the pressure gauge and the ink cartridge are connected in series in sequence, and the ink cartridge is connected to the nozzle through the nozzle board.

6. The screen inkjet device based on image processing according to claim 1, characterized in that: It also includes a nozzle wiping assembly, which includes a speed regulating motor, an unwinding shaft, a reeling shaft, a tension roller, a wiping cloth sensor and a wiping cloth, wherein the speed regulating motor is drivingly connected to the unwinding shaft; the reel formed by winding the wiping cloth is sleeved on the unwinding shaft and connected to the reeling shaft through the tension roller, and the wiping cloth sensor is arranged on one side of the tension roller.

7. The screen inkjet device based on image processing according to claim 1, characterized in that: The curing assembly includes a second double-motor X-axis linear motor module, a fourth dust-free drag chain, a manual fine-tuning unit, a curing lamp and a third adapter plate. The second double-motor X-axis linear motor module is drive-connected to the third adapter plate, and one end of the fourth dust-free drag chain is connected to the third adapter plate; the curing lamp is installed on the third adapter plate through the manual fine-tuning unit.

8. The screen inkjet device based on image processing according to claim 1, characterized in that: The automatic optical detection component includes a line scan camera, a strip coaxial light and a second image acquisition and analysis module, the signal output end of the line scan camera is connected to the second image acquisition and analysis module, and the signal output end of the second image acquisition and analysis module is connected to the inkjet component; The second image acquisition and analysis module performs frequency domain filtering on the image, divides the display screen into an ink area and a non-ink area, and performs defect analysis on noise points in the ink area and the non-ink area.

Images