Printed matter defect detection device

Abstract

The invention relates to a printed matter defect detection device, and belongs to the field of printed matter detection, the printed matter defect detection device comprises a rack, a feeding mechanism, a back plate, a hold-down mechanism, a reversing mechanism and a detection mechanism, the feeding mechanism is arranged on the rack and is used for feeding a to-be-detected double-sided printed matter and discharging the detected double-sided printed matter; at least two back plates are arranged on the rack and used for abutting against the face, away from the detection face, of the double-sided printed matter, the pressing and holding mechanism is arranged on the rack and used for pressing and holding the double-sided printed matter on the back plates, and the reversing mechanism is arranged on the rack and used for driving the detection face of the double-sided printed matter to be converted. The detection mechanism is arranged on the machine frame and used for conducting defect detection on the double-faced printed matter attached to the back plate. The method and the device have the effects of reducing shadows of patterns and characters on the surface, deviating from the detection surface, of the double-sided printed matter due to reflection and improving the accuracy of detecting the defects of the double-sided printed matter.

Description

Technical Field

[0001] This application relates to the field of printed matter inspection, and in particular to a device for detecting defects in printed matter. Background Technology

[0002] During the production process, printed materials are prone to defects such as uneven ink distribution, missing prints, scratches, and stains. Therefore, as the market's requirements for the quality of printed materials continue to increase, the importance of defect detection in printed materials is becoming increasingly prominent.

[0003] Currently, the main method for detecting defects in printed materials is visual inspection. This involves scanning the printed materials with a camera and then comparing the scanned image with a set standard image to achieve the purpose of detecting defects.

[0004] However, when inspecting defects in double-sided printed materials, since patterns and text are printed on both sides of the printed material, when inspecting one side of the printed material under light, the patterns and text on the other side of the printed material are easily projected onto the side being inspected, thus affecting the accuracy of the inspection. Summary of the Invention

[0005] To improve the accuracy of detecting defects in double-sided printed materials, this application provides a printing defect detection device.

[0006] The printing defect detection device provided in this application adopts the following technical solution: A printing defect detection device includes a frame, a feeding mechanism, a back plate, a pressing mechanism, a reversing mechanism, and a detection mechanism. The feeding mechanism is mounted on the frame and is used to feed double-sided printed materials to be inspected and to unload double-sided printed materials after inspection. At least two back plates are provided on the frame and are used to abut against the side of the double-sided printed material away from the inspection surface. The pressing mechanism is mounted on the frame and is used to press the double-sided printed material onto the back plate. The reversing mechanism is mounted on the frame and is used to drive the inspection surface of the double-sided printed material to change. The detection mechanism is mounted on the frame and is used to perform defect detection on the double-sided printed material attached to the back plate.

[0007] By adopting the above technical solution, the feeding mechanism feeds the completed double-sided printed material to be inspected, the holding mechanism presses the double-sided printed material onto the back plate, so that the side of the double-sided printed material away from the inspection surface is in contact with the back plate. Then, the inspection mechanism performs defect inspection on the section of the double-sided printed material that is in contact with the back plate. The reversing mechanism reverses the direction of the double-sided printed material that has been inspected on one side, and the holding mechanism presses the other side of the double-sided printed material onto another back plate. The inspection mechanism then inspects the other side of the double-sided printed material. Finally, the feeding mechanism unloads the inspected double-sided printed material, thus completing the defect inspection on both sides of the double-sided printed material. During inspection, by driving the side of the double-sided printed material away from the inspection surface to be in contact with the back plate, the shadows caused by reflection on the pattern and text on the side away from the inspection surface are reduced, thereby improving the accuracy of defect inspection of the double-sided printed material.

[0008] Optionally, the pressing mechanism includes a pressing seat, pressing rollers, a control component, and a width limiting component. The pressing seat is slidably mounted on the frame in the direction toward the back plate. Two pressing rollers are rotatably mounted on the pressing seat at intervals along the conveying direction of the double-sided printed material. The control component is mounted on the frame and is used to drive the pressing seat to slide. The width limiting component is mounted on the frame and is used to limit the displacement of the double-sided printed material along the length direction of the pressing rollers.

[0009] By adopting the above technical solution, the movement of double-sided printed materials along the length direction of the pressure roller is limited by the width limiting component, and the pressure roller is moved closer to the back plate by the control component. This allows the two pressure rollers to press the double-sided printed materials against the back plate, thus stably guiding the double-sided printed materials against the back plate for conveying and reducing the possibility of shadows appearing on the double-sided printed materials due to gaps between them and the back plate.

[0010] Optionally, the width limiting component includes a sliding seat, a roller, and a driving component. The sliding seat is slidably mounted on the frame along the length of the pressure roller. The roller is rotatably mounted on the sliding seat and abuts against the double-sided printed material on the back plate. The driving component is mounted on the frame and is used to drive the sliding seat to slide.

[0011] By adopting the above technical solution, the driving component drives the sliding seat to move towards the side of the double-sided printed material. The sliding seat drives the roller to press against the side of the double-sided printed material, which further improves the stability of the double-sided printed material on the back plate and reduces the possibility of the double-sided printed material curling up on the back plate.

[0012] Optionally, the reversing mechanism includes multiple guide rollers, all of which are rotatably mounted on the frame. The multiple guide rollers are used to reverse the conveying direction of the double-sided printed matter.

[0013] By adopting the above technical solution, after one side of the double-sided printed material is inspected, multiple guide rollers guide the continued conveying of the double-sided printed material, thereby changing the conveying direction of the double-sided printed material and driving the surface to be inspected of the double-sided printed material to be converted.

[0014] Optionally, the detection mechanism includes an adjustment base, a detection base, a camera module, a first control component, a second control component, a third control component, and a lighting assembly. The adjustment base is slidably mounted on the frame in the direction toward the back panel. The detection base is slidably mounted on the adjustment base in the direction toward the conveying direction of the double-sided printed material. The camera module is slidably mounted on the detection base in a direction perpendicular to the sliding direction of the detection base. The first control component is mounted on the frame and is used to drive the adjustment base to slide. The second control component is mounted on the adjustment base and is used to drive the detection base to slide. The third control component is mounted on the detection base and is used to drive the camera module to slide. The lighting assembly is mounted on the camera module and is used to illuminate the detection area of ​​the double-sided printed material.

[0015] By adopting the above technical solution, based on the width and thickness of the double-sided printed material to be inspected, the first control component drives the adjusting seat to slide, the second control component drives the detection seat to slide, and the third control component drives the degrading module to slide, thereby adjusting the distance between the camera module and the double-sided printed material and the center position of the camera module relative to the double-sided printed material, adjusting the camera module to a better detection position, and illuminating the detection area of ​​the double-sided printed material through the light component, improving the imaging effect of the camera module, and thus improving the accuracy of defect detection of the double-sided printed material.

[0016] Optionally, the lighting assembly includes a first support rod, a second support rod, a spotlight, a first adjustment member, and a second adjustment member. Two first and second support rods are slidably disposed on the camera module in opposite directions. The sliding direction of the second support rod is perpendicular to the sliding direction of the first support rod. The first adjustment member is disposed on the camera module and is used to drive the two first support rods to slide. The second adjustment member is disposed on the camera module and is used to drive the two second support rods to slide. One spotlight is disposed on each of the first and second support rods.

[0017] By adopting the above technical solution, when the position of the camera module is adjusted according to the width and imaging size of the double-sided printed material to be inspected, the lighting component is moved. Then, the first adjusting component drives the two first support frames to move closer or further apart, and the second adjusting component drives the two second support rods to move closer or further apart. This adjusts the area enclosed by the two first and two second support rods to match the width and imaging size of the double-sided printed material. The lights on the first and second support rods can then illuminate the double-sided printed material according to its width and imaging size, thus improving the lighting effect.

[0018] Optionally, the feeding mechanism includes a feeding frame, an upper feeding roller, an lower feeding roller, a locking element, and a winding element. The feeding frame is rotatably mounted on the machine frame. Multiple upper feeding rollers are rotatably mounted on the feeding frame at circumferential intervals. Multiple lower feeding rollers are rotatably mounted on the feeding frame at circumferential intervals. The multiple upper feeding rollers and multiple lower feeding rollers are symmetrically arranged on the feeding frame. The locking element is mounted on the machine frame and is used to lock the feeding frame. The winding element is mounted on the machine frame and is used to drive the lower feeding roller of the double-sided printed material that has completed winding detection to rotate.

[0019] By adopting the above technical solution, the operator places multiple rolls of double-sided printed materials to be inspected onto multiple feeding rollers. Then, the feeding frame is rotated so that one of the feeding rollers rotates to the feeding position. The feeding frame is locked by a locking device, and the double-sided printed materials on this feeding roller are pulled from the inspection conveying path to the unloading roller that supports this feeding roller. The unloading roller is driven to rotate by a winding device, and the unloading roller can pull the double-sided printed materials for conveying. This facilitates the feeding and unloading of double-sided printed materials. After the roll of double-sided printed materials on one feeding roller is fed, the locking device is released from the feeding frame. Then, the feeding frame is rotated so that another feeding roller with rolls of double-sided printed materials rotates to the feeding position. The locking device is then locked, which enables rapid switching between the feeding roller and the unloading roller, and quick switching between feeding and unloading double-sided printed materials.

[0020] Optionally, the winding component includes a winding motor and a coupling. The winding motor is mounted on the frame, and the coupling is mounted on the output shaft of the winding motor and is used to coaxially connect to the unloading roller of the double-sided printed material after winding detection.

[0021] By adopting the above technical solution, after the feeding frame drives the unloading roller to rotate to the unloading position, the output shaft of the winding motor is coaxially connected to the unloading roller through the coupling. When the winding motor is started, the unloading roller can be driven to rotate and the double-sided printed products that have been inspected are wound up.

[0022] Optionally, the frame is provided with a marking mechanism for marking defects on double-sided printed materials. The marking mechanism includes a marking base, a spray gun, a pusher, and a cutting assembly. The marking base is inclinedly arranged on the frame along the conveying direction of the double-sided printed materials. The spray gun is arranged on the marking base and is used to spray markings onto the defects of the printed materials. The pusher is arranged on the frame and is used to push the marking base to slide. The cutting assembly is arranged on the frame and is used to cut off the defects of the double-sided printed materials before they are wound onto the unwinding roller.

[0023] By adopting the above technical solution, after the camera module detects a defective double-sided printed product, it sprays a mark onto the double-sided printed product using a spray gun. At the same time, a pusher drives the mark holder to slide, and the mark holder drives the spray gun to move, so that the spray gun tilts to adapt to the conveying of the double-sided printed product. The spray gun can then spray a dividing line on the double-sided printed product. The subsequent cutting component can cut off the defective part of the double-sided printed product along the dividing line sprayed by the spray gun before it is rolled up to the unloading roller, thus conveniently realizing the defect handling of double-sided printed products.

[0024] Optionally, the cutting assembly includes a recognition camera, a cutter, a cutting component, and a control panel. At least two recognition cameras are mounted on the frame, with the two recognition cameras located on opposite sides of the double-sided printed material. The cutter is slidably mounted on the frame along the width direction of the double-sided printed material. The cutting component is mounted on the frame and is used to drive the cutter to slide. The control panel is mounted on the frame and electrically connected to the recognition camera, the cutting component, and the winding motor.

[0025] By adopting the above technical solution, after the camera identifies the dividing line of the spray gun, the control panel controls the winding motor to stop and controls the cutting component to drive the cutter to slide in the width direction of the double-sided printed material. The cutter can then cut the double-sided printed material along the cutting line.

[0026] In summary, this application includes at least one of the following beneficial technical effects: 1. Reduce shadows caused by reflection on the side of double-sided printed materials that is away from the inspection surface, thereby improving the accuracy of defect detection on double-sided printed materials; 2. Adjust the camera module to the optimal detection position and illuminate the detection area of ​​the double-sided printed material with the lighting component to improve the imaging effect of the camera module, thereby improving the accuracy of defect detection of the double-sided printed material; 3. After one of the feeding rollers has finished feeding the roll of double-sided printed material, release the locking device from the feeding frame, then rotate the feeding frame to rotate the other feeding roller with the roll of double-sided printed material to the feeding position, and then lock the locking device. This allows for quick switching between the feeding roller and the unloading roller, enabling rapid switching between feeding and unloading double-sided printed materials. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of the printing defect detection device according to an embodiment of this application.

[0028] Figure 2 This is a schematic diagram of the feeding mechanism in an embodiment of this application.

[0029] Figure 3 This is a schematic diagram of the structure of the back plate, pressing mechanism, detection mechanism and marking mechanism in an embodiment of this application.

[0030] Figure 4 This is a schematic diagram of the pressing mechanism according to an embodiment of this application.

[0031] Figure 5 This is a schematic diagram of the structure of the testing mechanism according to an embodiment of this application.

[0032] Figure 6 This is a schematic diagram of the structure of the cutting component according to an embodiment of this application.

[0033] Reference numerals: 1. Frame; 2. Feeding mechanism; 21. Feeding frame; 22. Upper roller; 23. Lower roller; 24. Locking element; 25. Rewinding element; 251. Rewinding motor; 252. Coupling; 3. Back plate; 4. Pressing mechanism; 41. Pressing seat; 42. Pressing roller; 43. Control element; 44. Width limiting assembly; 441. Sliding seat; 442. Roller; 443. Drive element; 5. Reversing mechanism; 51. Guide roller; 6. Detection mechanism; 61. Adjustment 62. Detection seat; 63. Camera module; 64. First control component; 65. Second control component; 66. Third control component; 67. Lighting assembly; 671. First support rod; 672. Second support rod; 673. Illuminator; 674. First adjustment component; 675. Second adjustment component; 7. Marking mechanism; 71. Marking seat; 72. Spray gun; 73. Pushing component; 74. Cutting assembly; 741. Identification camera; 742. Cutter; 743. Cutting component. Detailed Implementation

[0034] The following is in conjunction with the appendix Figure 1-6 This application will be described in further detail.

[0035] This application discloses a printing defect detection device.

[0036] Reference Figure 1 The printing defect detection device includes a frame 1, a feeding mechanism 2, a back plate 3, a holding mechanism 4, a reversing mechanism 5, a detection mechanism 6, and a marking mechanism 7.

[0037] Reference Figure 1 , Figure 2 The feeding mechanism 2 is mounted on the frame 1. The feeding mechanism 2 is used to load the double-sided printed materials to be inspected and unload the inspected double-sided printed materials. The feeding mechanism 2 includes a feeding frame 21, feeding rollers 22, unloading rollers 23, locking components 24, and winding components 25. The feeding frame 21 is rotatably mounted on the frame 1. Multiple feeding rollers 22 are rotatably mounted on the feeding frame 21, and the multiple feeding rollers 22 are circumferentially evenly spaced on the feeding frame 21. Multiple unloading rollers 23 are rotatably mounted on the feeding frame 21, and the multiple unloading rollers 23 are circumferentially evenly spaced on the feeding frame 21. The multiple feeding rollers 22 and the multiple unloading rollers 23 are at equal intervals. The rollers are staggered, so that multiple feeding rollers 22 and multiple unloading rollers 23 are symmetrically distributed on the feeding frame 21. In this embodiment, the feeding frame 21 has multiple notches for the feeding rollers 22 or unloading rollers 23 to be inserted. After the operator inserts the feeding rollers 22 or unloading rollers 23 into the notches, the locking bolts are threaded onto the feeding frame 21 at the notches, so that the locking bolts block the feeding rollers 22 or unloading rollers 23 in the notches. This allows for easy installation and removal of the feeding rollers 22 or unloading rollers 23 on the feeding frame 21, and thus allows for the feeding of rolls of double-sided printed materials onto the feeding rollers 22 and the unloading onto the unloading rollers 23.

[0038] Reference Figure 2 The locking member 24 is installed on the frame 1 and is used to lock the feeding frame 21. In this embodiment, the locking member 24 is a locking pin. The rotating shaft of the feeding frame 21 has multiple insertion holes spaced at circumferential intervals of the feeding roller 22. The locking pin is slidably installed on the frame 1. After the feeding frame 21 rotates by one circumferential interval of the feeding roller 22, the locking pin can be inserted into the corresponding insertion hole at this time, thereby locking the rotation of the feeding frame 21. The winding member 25 is installed on the frame 1 and is used to drive the unloading roller 23 of the double-sided printed material that has been wound and inspected to rotate. The winding member 25 includes a winding motor 251 and a coupling 252. The winding motor 251 is installed on the frame 1 and the coupling 252 is installed on the output shaft of the winding motor 251. The coupling 252 is coaxially connected to the unloading roller 23 of the double-sided printed material that has been wound and inspected.

[0039] In this embodiment, multiple guide rollers are also rotatably installed on the frame 1 along the conveying path of the double-sided printed material, which can support and guide the double-sided printed material on the conveying path.

[0040] Workers place multiple finished rolls of double-sided printed materials one by one onto multiple feeding rollers 22. Then, the double-sided printed materials are guided along the subsequent inspection conveyor path, passing over multiple guide rollers 51, and finally onto the unloading roller 23 connected to the coupling 252. The winding motor 251 is started, and through the coupling 252, it drives the unloading roller 23 to rotate, thus rewinding the double-sided printed materials. This facilitates the feeding and unloading of the double-sided printed materials along the inspection conveyor path. After the double-sided printed materials on the feeding rollers 22 have been fed, the locking device 24 is released from the feeder 2. Locking 1 releases the connection between coupling 252 and unloading roller 23. Then, rotating the feeder 21 causes the feed roller 22, which is fitted with a roll of double-sided printed material, to rotate to the feeding position. The feeder 21 drives the unloading roller 23 to rotate to the unloading position. Then, the feeder 21 is locked again by the locking member 24, and the coupling 252 is connected to the unloading roller 23, which is now in the unloading position. This allows for easy switching between the feeding roller 22 and the unloading roller 23. Restarting the winding motor 251 allows for the feeding, inspection, and unloading of the next roll of double-sided printed material, improving the efficiency and convenience of switching between feeding and unloading double-sided printed material.

[0041] Reference Figure 1 , Figure 2 Two back plates 3 are installed on the frame 1. Both back plates 3 are located on the conveying path of the double-sided printed matter. The two back plates 3 are respectively used to abut against the two sides of the double-sided printed matter. In this embodiment, pulleys are rotatably installed at both ends of the back plate 3 to reduce the friction between the double-sided printed matter and the ends of the back plate 3. The back plate 3 is covered with light-absorbing cloth to reduce the reflection of light from the back plate 3.

[0042] Reference Figure 1 , Figure 3 , Figure 4One pressing mechanism 4 is installed on each of the two back plates 3 on the frame 1. The pressing mechanism 4 is used to press the double-sided printed material onto the back plates 3. The pressing mechanism 4 includes a pressing seat 41, pressing rollers 42, a control component 43, and a width limiting component 44. The pressing seat 41 is slidably installed on the frame 1 along the direction facing the back plate 3 to adhere to the double-sided printed material. Two pressing rollers 42 are rotatably installed on the pressing seat 41. The length direction of the pressing rollers 42 is perpendicular to the conveying direction of the double-sided printed material. The two pressing rollers 42 are spaced apart along the conveying direction of the double-sided printed material. The control component 43 is installed on the frame 1 and is used to drive the pressing seat 41 to slide. In this embodiment, the control component 43 is a cylinder. The cylinder is installed on the frame 1, and the output shaft of the cylinder is connected to the pressing seat 41. The control component 43 controls the output shaft of the cylinder. The telescopic mechanism allows the pressure seat 41 to move closer to or away from the back plate 3. A width-limiting component 44 is mounted on the frame 1 and is used to limit the displacement of the double-sided printed material along the length of the pressure roller 42. The width-limiting component 44 includes a sliding seat 441, rollers 442, and a driving member 443. One sliding seat 441 is slidably mounted on the frame 1 at each end of the pressure roller 42 along its length. Multiple rollers 442 are rotatably mounted on the sliding seat 441, and the rotation direction of the rollers 442 is consistent with the conveying direction of the double-sided printed material. The driving member 443 is mounted on the frame 1 and is used to drive the sliding seat 441 to slide. In this embodiment, the driving member 443 is a cylinder, mounted on the frame 1, and the piston rod of the cylinder is connected to the sliding seat 441.

[0043] The operator first slides the sliding seat 441 of the drive component 443 according to the width of the double-sided printed material, so that the distance between the two sliding seats 441 is adapted to the width of the printed material. The sliding seat 441 can then drive the roller 442 to abut against the side of the double-sided printed material, thereby pressing the side of the double-sided printed material against the back plate 3, thus limiting the displacement of the double-sided printed material along the length direction of the pressure roller 42. At the same time, the control component 43 drives the pressure seat 41 to move towards the back plate 3. The pressure seat 41 drives the pressure roller 42 to move towards the back plate 3. The pressure roller 42 presses the double-sided printed material against the back plate 3, thus stably driving the double-sided printed material against the back plate 3 for conveying, maintaining the adhesion of the double-sided printed material on the back plate 3, reducing the possibility of shadows appearing on the double-sided printed material due to gaps between it and the back plate 3, and also reducing the possibility of the double-sided printed material curling up on the back plate 3.

[0044] Reference Figure 1 The reversing mechanism 5 is mounted on the frame 1. The reversing mechanism 5 is used to drive the detection surface of the double-sided printed matter to change. The reversing mechanism 5 includes multiple guide rollers 51. The multiple guide rollers 51 are used to guide the conveying direction of the double-sided printed matter to the reversing direction by allowing the double-sided printed matter to be wound around them.

[0045] After one side of the double-sided printed material has been inspected for defects, the double-sided printed material is bypassed by multiple guide rollers 51. The multiple guide rollers 51 guide the conveying direction of the double-sided printed material to a reversal, which allows the inspected side of the double-sided printed material to be switched with the uninspected side, making it convenient to switch the inspected side of the double-sided printed material.

[0046] Reference Figure 3 , Figure 5 The inspection mechanism 6 is mounted on the frame 1. The inspection mechanism 6 is used to inspect double-sided printed materials adhered to the back panel 3 for defects. The inspection mechanism 6 includes an adjustment seat 61, an inspection seat 62, a camera module 63, a first control component 64, a second control component 65, a third control component 66, and a lighting assembly 67. The adjustment seat 61 is slidably mounted on the frame 1 in the direction toward the back panel 3. The detection seat 62 is slidably mounted on the adjustment seat 61 in the direction of conveying the double-sided printed matter. The camera module 63 is slidably mounted on the detection seat 62 in a direction perpendicular to the sliding direction of the detection seat 62. In this embodiment, the camera module 63 includes an acquisition module for capturing images, a processing module for processing the acquired images, a detection module for comparing the processed images with a comparison template, and an output module for outputting the detection structure as an electrical signal. The first control member 64 is mounted on the frame 1 and is used to drive the adjustment seat 61 to slide. The second control member 65 is mounted on the adjustment seat 61 and is used to drive the detection seat 62 to slide. The third control member 66 is mounted on the detection seat 62 and is used to drive the camera module 63 to slide. In this embodiment, the first control member 64, the second control member 65, and the third control member 66 are all cylinders.

[0047] Reference Figure 3 , Figure 5 A lighting assembly 67 is mounted on the camera module 63. The lighting assembly 67 is used to illuminate the detection area of ​​double-sided printed materials. The lighting assembly 67 includes a first support rod 671, a second support rod 672, a lamp 673, a first adjusting member 674, and a second adjusting member 675. Two first support rods are slidably mounted parallel to each other on the camera module 63. Two second support rods 672 are slidably mounted on the camera module 63 in a direction perpendicular to the sliding direction of the first support rods. The two second support rods are parallel to each other. The first adjusting member 674 is mounted on the camera module 63 and is used to drive the two first support rods 671 to slide. The second adjusting member 675 is mounted on the camera module 63 and is used to drive the two second support rods 672 to slide. In this embodiment, both the first adjusting member 674 and the second adjusting member 675 are cylinders. One lamp 673 is mounted on each of the first support rods 671 and the second support rod 672. In this embodiment, the lamp 673 is an LED lamp.

[0048] Based on the width and thickness of the double-sided printed material to be inspected and the size of the image captured by the camera module 63 each time, the first control unit 64 drives the adjusting seat 61 to slide the detection seat 62 and the camera module 63 in the direction towards the back plate 3. The second control unit 65 drives the detection seat 62 to slide the camera module 63 in the direction of conveying the double-sided printed material. The third control unit 66 drives the camera module 63 to slide in a direction perpendicular to the sliding direction of the detection seat 62. This adjusts the distance between the camera module 63 and the double-sided printed material, as well as the center position of the camera module 63 relative to the double-sided printed material, so that the camera module 63 can capture the best image of the double-sided printed material on the back plate 3. The camera module 63 moves the lighting assembly 67, and through the first adjusting member 674, it drives the two first support frames to move closer or further apart, and through the second adjusting member 675, it drives the two second support rods 672 to move closer or further apart. This adjusts the area enclosed by the two first support rods 671 and the two second support rods 672 to match the width and image size of the double-sided printed material. The illumination lamps 673 on the first support rods 671 and the second support rods 672 can then illuminate the double-sided printed material according to its width and image size, improving the imaging effect of the camera module 63 and thus enhancing the accuracy of defect detection of the double-sided printed material.

[0049] Reference Figure 1 , Figure 3 , Figure 6The marking mechanism 7 is mounted on the frame 1. The marking mechanism 7 is used to mark defects on double-sided printed materials. The marking mechanism 7 includes a marking base 71, a spray gun 72, a pusher 73, and a cutting assembly 74. The marking base 71 is slidably mounted on the frame 1 along the conveying direction of the double-sided printed materials. The spray gun 72 is mounted on the marking base 71 and is connected to a pigment tank for spraying markings onto the double-sided printed materials under the action of an air compressor. The pusher 73 is mounted on the frame 1 and is used to push the marking base 71 to slide. The cutting assembly 74 is mounted on the frame 1 and is used to cut the marked double-sided printed materials before they are wound onto the unwinding roller 23. 74 includes an identification camera 741, a cutter 742, a cutting element 743, and a control panel. Two identification cameras 741 are mounted on the frame 1, located on either side of the double-sided printed material before it is wound up to the unloading roller 23. The cutter 742 is slidably mounted on the frame 1 along the side of the double-sided printed material. The cutting element 743 is mounted on the frame 1 and is used to drive the cutter 742 to slide. In this embodiment, the cutting element 743 is a cylinder. The control panel is mounted on the frame 1 and is electrically connected to the identification camera 741, the cutting element 743, the winding motor 251, the camera module 63, the pusher 73, and the spray gun 72.

[0050] After the camera module 63 detects a defective double-sided printed product, it sends an electrical signal to the control panel. The control panel then activates the spray gun 72 and controls the pusher 73 to slide the marker seat 71. The marker seat 71 causes the spray gun 72 to tilt and slide along the conveying direction of the double-sided printed product. The spray gun 72 thus tilts and moves along the conveying direction of the double-sided printed product, spraying a dividing line along the width of the double-sided printed product. This facilitates the subsequent cutting blade 742 to remove defects from the double-sided printed product. When the defective section of the double-sided printed material is continuously conveyed to the position of the recognition camera 741, the recognition camera 741 recognizes the dividing line sprayed on the double-sided printed material. The control panel controls the winding motor 251 to stop and controls the cutting component 743 to start. The cutting component 743 drives the cutter 742 to move from one side of the double-sided printed material to the other side in the width direction of the double-sided printed material. The cutter 742 can then cut off the defective section of the double-sided printed material along the cutting line, which facilitates the processing of the defective section of the double-sided printed material.

[0051] The implementation principle of the printing defect detection device in this application embodiment is as follows: A roll of double-sided printed material on the feeding roller 22 is pulled sequentially through a back plate 3, a reversing mechanism 5, and another back plate 3, and then wound onto the unloading roller 23. The winding motor 251 drives the unloading roller 23 to rotate, thus pulling the double-sided printed material along the conveying path. During this process, the holding mechanism 4 presses the double-sided printed material onto the back plate 3, so that the side of the double-sided printed material away from the detection surface is in contact with the back plate 3. The camera module 63 can then collect images of the double-sided printed material on the back plate 3 for comparative detection. If a defect exists, the spray gun 72 can spray a dividing line onto the defective area of ​​the double-sided printed material, and then guide... Roller 51 guides the double-sided printed material to the opposite direction, and another pressing mechanism 4 presses the other side of the double-sided printed material onto another back plate 3. Camera module 63 detects the other side of the double-sided printed material, and then unloading roller 23 rolls up the detected double-sided printed material. If the double-sided printed material has defects, before the subsequent double-sided printed material is rolled up to unloading roller 23, cutting component 74 cuts off the defective part of the double-sided printed material. When the camera module 63 captures the image, the double-sided printed material is pressed against and adhered to the back plate 3 to reduce the shadows caused by reflection on the side of the double-sided printed material that is away from the detection surface, thereby improving the accuracy of detecting defects in the double-sided printed material.

[0052] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A printing defect detection device, characterized in that: The device includes a frame (1), a feeding mechanism (2), a back plate (3), a pressing mechanism (4), a reversing mechanism (5), and a detection mechanism (6). The feeding mechanism (2) is mounted on the frame (1) and is used to feed the double-sided printed material to be inspected and to unload the double-sided printed material after inspection. The back plate (3) is mounted on the frame (1) with at least two parts and is used to contact the side of the double-sided printed material away from the inspection surface. The pressing mechanism (4) is mounted on the frame (1) and is used to press the double-sided printed material onto the back plate (3). The reversing mechanism (5) is mounted on the frame (1) and is used to drive the inspection surface of the double-sided printed material to change. The detection mechanism (6) is mounted on the frame (1) and is used to perform defect detection on the double-sided printed material attached to the back plate (3).

2. The printing defect detection device according to claim 1, characterized in that: The pressing mechanism (4) includes a pressing seat (41), a pressing roller (42), a control component (43), and a width limiting component (44). The pressing seat (41) is slidably mounted on the frame (1) in the direction toward the back plate (3). Two pressing rollers (42) are rotatably mounted on the pressing seat (41) at intervals along the conveying direction of the double-sided printed matter. The control component (43) is mounted on the frame (1) and is used to drive the pressing seat (41) to slide. The width limiting component (44) is mounted on the frame (1) and is used to limit the displacement of the double-sided printed matter along the length direction of the pressing roller (42).

3. The printing defect detection device according to claim 2, characterized in that: The width limiting component (44) includes a sliding seat (441), a roller (442) and a driving member (443). The sliding seat (441) is slidably disposed on the frame (1) along the length direction of the pressure roller (42). The roller (442) is rotatably disposed on the sliding seat (441) and abuts against the double-sided printed material on the back plate (3). The driving member (443) is disposed on the frame (1) and is used to drive the sliding seat (441) to slide.

4. The printing defect detection device according to claim 1, characterized in that: The reversing mechanism (5) includes multiple guide rollers (51), all of which are rotatably mounted on the frame (1). The multiple guide rollers (51) are used to drive the conveying direction of the double-sided printed matter to change direction.

5. The printing defect detection device according to claim 1, characterized in that: The detection mechanism (6) includes an adjustment seat (61), a detection seat (62), a camera module (63), a first control component (64), a second control component (65), a third control component (66), and a lighting assembly (67). The adjustment seat (61) is slidably mounted on the frame (1) in the direction toward the back plate (3). The detection seat (62) is slidably mounted on the adjustment seat (61) in the direction toward the conveying direction of the double-sided printed matter. The camera module (63) slides in a direction perpendicular to the detection seat (62). The first control unit (64) is mounted on the frame (1) and is used to drive the adjustment unit (61) to slide. The second control unit (65) is mounted on the adjustment unit (61) and is used to drive the detection unit (62) to slide. The third control unit (66) is mounted on the detection unit (62) and is used to drive the camera module (63) to slide. The light assembly (67) is mounted on the camera module (63) and is used to illuminate the detection area of ​​the double-sided printed matter.

6. The printing defect detection device according to claim 5, characterized in that: The lighting assembly (67) includes a first support rod (671), a second support rod (672), a spotlight (673), a first adjustment member (674), and a second adjustment member (675). Two of the first support rods (671) and the second support rods (672) are slidably arranged on the camera module (63) in opposite directions. The sliding direction of the second support rod (672) is perpendicular to the sliding direction of the first support rod (671). The first adjustment member (674) is arranged on the camera module and is used to drive the two first support rods (671) to slide. The second adjustment member (675) is arranged on the camera module and is used to drive the two second support rods (672) to slide. One spotlight (673) is arranged on each of the first support rods (671) and the second support rods (672).

7. The printing defect detection device according to claim 1, characterized in that: The feeding mechanism (2) includes a feeding frame (21), an upper roller (22), an lower roller (23), a locking member (24), and a winding member (25). The feeding frame (21) is rotatably mounted on the frame (1). Multiple upper rollers (22) are rotatably mounted on the feeding frame (21) at circumferential intervals. Multiple lower rollers (23) are rotatably mounted on the feeding frame (21) at circumferential intervals. Multiple upper rollers (22) and multiple lower rollers (23) are symmetrically mounted on the feeding frame (21). The locking member (24) is mounted on the frame (1) and is used to lock the feeding frame (21). The winding member (25) is mounted on the frame (1) and is used to drive the lower roller (23) of the double-sided printed material that has completed winding detection to rotate.

8. A printing defect detection device according to claim 7, characterized in that: The winding component (25) includes a winding motor (251) and a coupling (252). The winding motor (251) is mounted on the frame (1), and the coupling (252) is mounted on the output shaft of the winding motor (251) and is used to coaxially connect to the unloading roller (23) of the double-sided printed matter after the winding inspection is completed.

9. A printing defect detection device according to claim 8, characterized in that: The frame (1) is provided with a marking mechanism (7) for marking defects on double-sided printed materials. The marking mechanism (7) includes a marking seat (71), a spray gun (72), a pusher (73), and a cutting assembly (74). The marking seat (71) is inclinedly arranged on the frame (1) along the conveying direction of the double-sided printed materials. The spray gun (72) is arranged on the marking seat (71) and is used to spray markings onto the defects of the printed materials. The pusher (73) is arranged on the frame (1) and is used to push the marking seat (71) to slide. The cutting assembly (74) is arranged on the frame (1) and is used to cut off the defects of the double-sided printed materials before they are wound onto the unloading roller (23).

10. A printing defect detection device according to claim 9, characterized in that: The cutting assembly (74) includes an identification camera (741), a cutter (742), a cutting component (743), and a control panel. At least two identification cameras (741) are provided on the frame (1), and the two identification cameras (741) are respectively located on both sides of the double-sided printed matter. The cutter (742) is slidably disposed on the frame (1) in the direction of the width of the double-sided printed matter. The cutting component (743) is disposed on the frame (1) and is used to drive the cutter (742) to slide. The control panel is disposed on the frame (1) and is electrically connected to the identification camera (741), the cutting component (743), and the winding motor (251).

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