Image analysis-based aluminum foil reverse roll surface defect detection device and detection method

Abstract

The present application relates to the technical field of aluminum foil detection, in particular to an aluminum foil reverse winding surface defect detection device and method based on image analysis, the aluminum foil reverse winding surface defect detection device based on image analysis comprises a top plate and two frame bodies respectively arranged on the two sides of the top plate, further comprising: an image sensor mounted on the top plate, used for acquiring surface image information of the aluminum foil; two groups of clamping and pulling units respectively arranged on the two frame bodies, comprising two horizontally distributed cross arms, a clamping plate movably arranged on the cross arm, and a plurality of clamping tentacles equidistantly arranged on the clamping plate along the direction of the aluminum foil; the clamping and pulling unit clamps the side edge of the aluminum foil, and then pulls it with appropriate force along the direction perpendicular to the direction of the aluminum foil, thereby offsetting the elastic contraction of the aluminum foil in the width direction caused by the pulling force in the direction of the aluminum foil during the reverse winding process, reducing stress concentration and surface unevenness caused by width changes, and providing a more stable and clearer detection surface for the image sensor.

Description

Technical Field

[0001] This invention relates to the field of aluminum foil inspection technology, specifically to an aluminum foil rewinding surface defect detection device and method based on image analysis. Background Technology

[0002] Aluminum foil is a thin, sheet-like material made from aluminum. It is lightweight, malleable, and has good electrical and thermal conductivity, making it widely used. Pinholes are one of the most common defects in aluminum foil, appearing as tiny holes on the surface. These holes are typically small in diameter and may be round or irregular in shape. The main cause is inadequate cleaning of the raw material during aluminum foil production, resulting in impurities such as oil, sweat, and dust. These impurities cause gases to be generated during melting, leading to pinholes. Pinholes reduce the barrier properties of the aluminum foil, weakening its moisture-proof and gas-proof functions, thus affecting its performance.

[0003] Therefore, surface defect detection of aluminum foil is an essential process in aluminum foil production. Currently, surface defect detection of aluminum foil typically involves intermittent rewinding, during which image sensors are used to acquire surface information and detect defects.

[0004] However, when aluminum foil is rolled up, its direction of travel is subjected to tension (to ensure that the aluminum foil maintains a certain degree of tension). This can easily lead to elastic contraction in the width direction of the aluminum foil, which can easily cause stress concentration and surface unevenness. The aluminum foil maintains a relatively stable size and shape in the width direction. Pinholes may be difficult to accurately identify due to factors such as wrinkles on the aluminum foil surface and light reflection. Therefore, existing detection methods, which place image sensors directly above or below the aluminum foil, may have difficulty acquiring stable and clear images due to these adverse factors, resulting in poor accuracy and reliability of defect detection. Summary of the Invention

[0005] The purpose of this invention is to provide an image analysis-based device and method for detecting surface defects in aluminum foil roll-up, in order to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] The image analysis-based aluminum foil rewinding surface defect detection device includes a top plate and two frames respectively disposed on both sides of the top plate, and further includes:

[0008] An image sensor mounted on the top plate is used to acquire surface image information of the aluminum foil;

[0009] Two sets of clamping and pulling units are respectively set on two frames, including two horizontal arms distributed vertically. A clamping plate is movably installed on the horizontal arm. Multiple clamping tentacles are equidistantly arranged on the clamping plate along the direction of aluminum foil travel. The two horizontal arms can be driven by two sets of power mechanisms on the frame to move towards each other, so that the clamping tentacles located above and below the aluminum foil can perform clamping actions on the side of the aluminum foil.

[0010] During testing, the clamping and pulling unit pulls the side of the aluminum foil once and twice in succession. The image sensor acquires the first image and the second image respectively. After each pull ends and before the second pull, the clamping plate is moved by the displacement structure on the horizontal arm so that the position of the multiple clamping tentacles changes in the direction of aluminum foil travel.

[0011] As a further aspect of the present invention: the length direction of the horizontal arm is parallel to the travel direction of the aluminum foil, the switching structure includes a movable arm slidably sleeved on the horizontal arm, the clamping plate is fixed to the movable arm, and the movable arm can be driven to move by a pneumatic component provided on the horizontal arm so as to change the position of the plurality of clamping tentacles in the travel direction of the aluminum foil.

[0012] As a further embodiment of the present invention: the pneumatic assembly includes an assembly arm fixedly mounted on the cross arm and a first cylinder rotatably mounted on the assembly arm, wherein the movable end of the first cylinder is hinged to the movable arm.

[0013] As a further embodiment of the present invention: the frame is provided with a first guide rail, and the power mechanism includes two sets of sliding structures symmetrically arranged on the first guide rail. The two sets of sliding structures are respectively connected to the two cross arms. The two sets of sliding structures can be driven by a threaded drive member installed on the frame to slide closer to or further away from each other on the first guide rail.

[0014] As a further embodiment of the present invention: the sliding structure includes a first slider and a second slider that are slidably fitted on the first guide rail. An elastic element is provided between the first slider and the second slider. The first slider is connected to the threaded drive element. A driven component is provided between the second slider and the cross arm. When the aluminum foil is clamped, the first slider and the second slider move relative to each other, and the driven component is triggered, causing the cross arm to move closer to the second slider.

[0015] As a further embodiment of the present invention: the elastic element includes a column disposed on the second slider and a cylindrical spring sleeved on the outer periphery of the column, the column passes through the first slider and the first slider is slidably connected to the column, and the two ends of the cylindrical spring are respectively connected to the first slider and the second slider.

[0016] As a further embodiment of the present invention: the driven component includes a guide arm and a telescopic arm fixed to the second slider and the cross arm respectively. The guide arm and the telescopic arm are slidably fitted together. A column is fixedly provided on the first slider by a support arm. A transmission plate is provided on the telescopic arm. The transmission plate is provided with a through groove adapted to the column. The column passes through the through groove and is slidably connected to the transmission plate. The through groove includes a vertical section and an inclined section connected together.

[0017] As a further embodiment of the present invention: the top plate is provided with two sets of cleaning mechanisms on the side facing the aluminum foil traveling direction. The cleaning mechanism includes a first motor movably disposed above the aluminum foil, an assembly seat disposed at the output end of the first motor, and a cleaning roller rotatably mounted on the assembly seat. The assembly seat is also provided with a second motor for driving the cleaning roller to rotate, and the top plate is provided with a lifting structure for driving the cleaning roller to rise and fall.

[0018] As a further embodiment of the present invention: the lifting structure includes a second guide rail disposed on the side of the frame, a vertical arm slidably connected to the second guide rail, and a second cylinder rotatably mounted on the top plate, the movable end of the second cylinder being hinged to the vertical arm, and the first motor being mounted on the vertical arm.

[0019] As a further embodiment of the present invention: a method for detecting surface defects of aluminum foil during rewinding, using the aforementioned detection device, wherein a cleaning mechanism cleans the surface of the aluminum foil before it enters the detection area;

[0020] After the aluminum foil enters the detection area, the power mechanism drives the two horizontal arms to move closer together, causing multiple gripping tentacles to clamp the aluminum foil. Then, the aluminum foil is pulled perpendicular to the direction of travel, and the image sensor acquires the first image. Subsequently, the repositioning structure drives the clamping plate to move, changing the position of the multiple gripping tentacles in the direction of travel of the aluminum foil. The aluminum foil is then clamped again and pulled a second time, and the image sensor acquires the second image. The processor combines the first image and the second image to form a complete image of the aluminum foil surface, and then performs defect analysis.

[0021] Compared with the prior art, the beneficial effects of the present invention are:

[0022] This application sets up a set of clamping and pulling units on both sides of the aluminum foil. The clamping and pulling units clamp the sides of the aluminum foil in advance, and then pull it with appropriate force along the direction perpendicular to the aluminum foil's travel direction. This effectively counteracts the elastic contraction in the width direction of the aluminum foil caused by the pulling force in the travel direction during the unwinding process, so that the aluminum foil maintains a relatively stable size and shape in the width direction. This not only helps to improve the flatness of the aluminum foil surface and reduce stress concentration and surface unevenness caused by width changes, but also provides a more stable and clearer detection surface for the image sensor. It avoids the possibility that pinholes may be difficult to accurately identify due to factors such as wrinkles and light reflection on the aluminum foil surface, thus improving the accuracy and reliability of pinhole detection.

[0023] Secondly, each detection includes one pull and two pulls. The image sensor acquires the first image and the second image respectively. Specifically, after each pull ends and before the second pull, the clamping plate is driven to move by the displacement structure on the cross arm, so that the position of multiple clamping tentacles in the aluminum foil traveling direction changes. The multiple clamping tentacles are offset from their previous positions, so the part of the aluminum foil being clamped changes, realizing the displacement clamping function. This avoids the problem of occlusion due to the fixed clamping position, which would result in an incomplete image of the aluminum foil surface acquired by the image sensor.

[0024] Furthermore, during the pulling process, the distance between the first and second sliders continuously decreases, the compression of the cylindrical spring and the force on the aluminum foil gradually increase. The initial small force prevents the aluminum foil from being damaged by sudden force, and as the pulling progresses, the force gradually increases, so that the aluminum foil is evenly stressed in the width direction, maintaining stable pulling, uniform tension distribution, suppressing wrinkles and ripples, preventing slack slippage, providing a flat and clear detection surface for the image sensor, and improving the accuracy and reliability of pinhole detection. Attached Figure Description

[0025] Figure 1 An isometric view of one embodiment of an image analysis-based aluminum foil rewinding surface defect detection device.

[0026] Figure 2 This is a schematic diagram of one embodiment of an image analysis-based aluminum foil rewinding surface defect detection device.

[0027] Figure 3 This is a schematic diagram of another aspect of an embodiment of an image analysis-based aluminum foil rewinding surface defect detection device.

[0028] Figure 4 This is a structural schematic diagram from another angle of one embodiment of an image analysis-based aluminum foil rewinding surface defect detection device.

[0029] Figure 5 This is a front view of an embodiment of an image analysis-based aluminum foil rewinding surface defect detection device.

[0030] Figure 6 for Figure 4 Enlarged view of the structure at point A in the middle.

[0031] Figure 7 This is a schematic diagram of the connection state between the top plate and the frame in one embodiment of an image analysis-based aluminum foil rewinding surface defect detection device.

[0032] Figure 8 for Figure 7 A structural diagram from another angle.

[0033] Figure 9 This is a schematic diagram of the clamping and pulling unit in one embodiment of an image analysis-based aluminum foil rewinding surface defect detection device.

[0034] Figure 10 This is a schematic diagram of the clamping and pulling unit from another angle in one embodiment of an image analysis-based aluminum foil rewinding surface defect detection device.

[0035] Figure 11 This is an exploded view of the structure of the clamping and pulling unit in one embodiment of an image analysis-based aluminum foil rewinding surface defect detection device.

[0036] Figure 12 This is a schematic diagram of the cleaning mechanism in one embodiment of an image analysis-based aluminum foil rewinding surface defect detection device.

[0037] Figure 13 This is a top view of the cleaning mechanism in one embodiment of an image analysis-based aluminum foil rewinding surface defect detection device.

[0038] In the diagram: 1. Top plate; 2. Frame; 3. Image sensor; 4. Clamping plate; 5. Clamping hand; 501. Rubber pad; 6. Movable arm; 7. Horizontal arm; 8. Assembly arm; 9. First cylinder; 10. Transmission plate; 1001. Vertical section; 1002. Inclined section; 11. Guide arm; 12. Telescopic arm; 13. Column; 14. First slider; 15. Second slider; 16. First guide rail; 17. Vertical arm; 18. Second cylinder; 19. First motor; 20. Assembly base; 21. Second motor; 22. Cleaning roller; 23. Cylindrical spring; 24. Second guide rail; 25. Support arm; 26. Column. Detailed Implementation

[0039] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0040] Furthermore, elements in this invention are referred to as being "disposed on" or "located on" another element, which may be directly on the other element or may also include an intervening element. When an element is considered to be "connected" to another element, it may be directly connected to the other element or may also include an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0041] Please see Figures 1-13 In this embodiment of the invention, the aluminum foil rewinding surface defect detection device based on image analysis includes a top plate 1 and two frames 2 respectively disposed on both sides of the top plate 1, and further includes:

[0042] An image sensor 3 mounted on the top plate 1 is used to acquire surface image information of the aluminum foil;

[0043] Two sets of clamping and pulling units are respectively set on two frames 2, including two horizontal arms 7 distributed vertically. A clamping plate 4 is movably provided on the horizontal arm 7. Multiple clamping tentacles 5 are equidistantly arranged on the clamping plate 4 along the direction of aluminum foil travel. The two horizontal arms 7 can be driven by two sets of power mechanisms on the frame 2 to move towards each other, so that the clamping tentacles 5 located above and below the aluminum foil can perform clamping action on the side of the aluminum foil.

[0044] During testing, the clamping and pulling unit pulls the side of the aluminum foil once and twice in succession. The image sensor 3 acquires the first image and the second image respectively. After each pull ends and before the second pull, the clamping plate 4 is driven to move by the displacement structure on the horizontal arm 7 so that the position of the multiple clamping tentacles 5 changes in the direction of aluminum foil travel.

[0045] It should be noted that during actual rewinding, corresponding guide wheels need to be installed on both sides of the device to guide the aluminum foil. It is necessary to ensure that the aluminum foil on the path of this device remains straight at all times in order to facilitate smooth detection.

[0046] It should be added that the detection principle of the image sensor 3 is as follows: when light shines on the surface of aluminum foil, the complete aluminum foil surface reflects or absorbs the light, while the light at the pinhole will penetrate the aluminum foil and form a point or area on the image sensor 3 with a different gray level than the surrounding area. The sensor captures this difference and analyzes it through the image processing algorithm to identify the pinhole defect.

[0047] In conjunction with this application, the clamping and pulling unit clamps the sides of the aluminum foil beforehand, and then pulls it with appropriate force along the direction perpendicular to the aluminum foil's travel direction. This effectively counteracts the elastic contraction in the width direction of the aluminum foil caused by the pulling force in the travel direction during the unwinding process, thereby maintaining a relatively stable size and shape of the aluminum foil in the width direction. This not only helps to improve the flatness of the aluminum foil surface and reduce stress concentration and surface unevenness caused by width changes, but also provides a more stable and clearer detection surface for the image sensor 3. It avoids the possibility that pinholes may be difficult to accurately identify due to factors such as wrinkles and light reflection on the aluminum foil surface, thus improving the accuracy and reliability of pinhole detection.

[0048] Secondly, after each pull ends and before the second pull, the clamping plate 4 is moved by the displacement structure set on the cross arm 7, so that the position of the multiple clamping tentacles 5 in the aluminum foil traveling direction changes. The multiple clamping tentacles 5 are offset from their previous positions, so the part of the aluminum foil being clamped changes, avoiding the problem of occlusion due to the fixed clamping position, which would result in an incomplete image of the aluminum foil surface acquired by the image sensor 3.

[0049] When analyzing the primary and secondary images acquired by the image sensor 3, the processor will combine the primary and secondary images to form a complete aluminum foil surface image, so as to perform a complete analysis of the aluminum foil surface information.

[0050] Please refer to it again. Figure 10 and Figure 11 The length direction of the horizontal arm 7 is parallel to the aluminum foil travel direction. The switching structure includes a movable arm 6 slidably sleeved on the horizontal arm 7. The clamping plate 4 is fixed to the movable arm 6. The movable arm 6 can be moved by a pneumatic component mounted on the horizontal arm 7 to change the position of the plurality of clamping tentacles 5 in the aluminum foil travel direction. The pneumatic component includes an assembly arm 8 fixedly mounted on the horizontal arm 7 and a first cylinder 9 rotatably mounted on the assembly arm 8. The movable end of the first cylinder 9 is hinged to the movable arm 6.

[0051] When inspecting a certain position of the aluminum foil, before the second clamping and pulling, the moving end of the first cylinder 9 moves, which drives the moving arm 6 to slide on the horizontal arm 7. As a result, the positions of the multiple clamping tentacles 5 in the aluminum foil traveling direction will change, and each clamping tentacle 5 will be offset from its previous position. This allows the part of the aluminum foil surface that was clamped during the first clamping and pulling to be exposed, ensuring the integrity of the inspection.

[0052] It should be added that during the testing process, the degree of tension of the clamping and pulling unit on the aluminum foil must be strictly controlled to ensure that the strain generated by the aluminum foil is within its elastic limit. Specifically, tests can be conducted in advance to determine the maximum strain value of aluminum foil of different thicknesses and materials within the elastic range. Based on this, the tension amount can be set. This can avoid damage to the aluminum foil due to excessive stretching and can also improve the detection rate of pinholes to a certain extent.

[0053] To reduce local stress concentration, a softer and more uniform clamping material and method are adopted. To this end, each of the clamping tentacles 5 is provided with a rubber pad 501 on the side facing the aluminum foil. The rubber pad 501 is used as the clamping surface to increase the clamping area and make the stress distribution more uniform.

[0054] Please refer to it again. Figure 3 , Figure 6 , Figure 9 as well as Figure 11 The frame 2 is provided with a first guide rail 16. The power mechanism includes two sets of sliding structures symmetrically arranged on the first guide rail 16. The two sets of sliding structures are respectively connected to the two cross arms 7. The two sets of sliding structures can be driven by a threaded drive member installed on the frame 2 to slide closer to or further away from each other on the first guide rail 16. The sliding structure includes a first slider 14 and a second slider 15 slidably fitted on the first guide rail 16. An elastic element is provided between the first slider 14 and the second slider 15. The first slider 14 is connected to the threaded drive member. A driven component is provided between the second slider 15 and the cross arm 7. When the aluminum foil is clamped, the first slider 14 and the second slider 15 move relative to each other, and the driven component is triggered, causing the cross arm 7 to move closer to the second slider 15. The elastic element includes a column 13 disposed on the second slider 15 and a cylindrical spring 23 sleeved on the outer periphery of the column 13. The column 13 passes through the first slider 14, and the first slider 14 is slidably connected to the column 13. The two ends of the cylindrical spring 23 are respectively connected to the first slider 14 and the second slider 15. The driven component includes a guide arm 11 and a telescopic arm 12 fixed to the second slider 15 and the cross arm 7, respectively. The guide arm 11 and the telescopic arm 12 are slidably fitted together. A column 26 is fixedly disposed on the first slider 14 by a support arm 25. A transmission plate 10 is disposed on the telescopic arm 12. The transmission plate 10 is provided with a through groove adapted to the column 26. The column 26 passes through the through groove and is slidably connected to the transmission plate 10. The through groove includes a vertical section 1001 and an inclined section 1002 connected together.

[0055] Specifically, the threaded drive component includes a bidirectional lead screw (not labeled in the figure) rotatably mounted on the frame 2 and two threaded sleeves symmetrically sleeved on the bidirectional lead screw. The two threaded sleeves are respectively fixedly connected to two first sliders 14 located on the first guide rail 16. When the bidirectional lead screw rotates, the two threaded sleeves engage with the bidirectional lead screw, thereby causing the two first sliders 14 on the first guide rail 16 to move closer or further away from each other, thus realizing the clamping function of the clamping tentacles 5 on the aluminum foil. This threaded engagement drive method has high driving accuracy and good stability, thus effectively controlling the pulling accuracy.

[0056] The two first sliders 14 on the first guide rail 16 move closer to each other. Before the clamping contact 5 contacts the side of the aluminum foil, the second slider 15 moves together with the first slider 14. After the clamping contact 5 contacts the side of the aluminum foil, the first slider 14 and the second slider 15 move relative to each other. The first slider 14 gradually moves closer to the second slider 15. During this process, the column spring 23 is compressed and the column 26 slides along the vertical section 1001 and the inclined section 1002 in sequence.

[0057] In detail, after the column 26 moves along the vertical section 1001, the compression of the column spring 23 is increased to a sufficient amount, so that the clamping contact 5 has sufficient clamping force to pull the aluminum foil. Then, after the column 26 enters the inclined section 1002, it will slide with the transmission plate 10. The transmission plate 10 will give way, causing the telescopic arm 12 to slide towards the second slider 15 on the guide arm 11. Then, the telescopic arm 12 will drive the clamping plate 4 to move in a direction perpendicular to the aluminum foil's travel direction through the horizontal arm 7 and the movable arm 6. Thus, the aluminum foil is pulled in a direction perpendicular to the travel direction, improving the accuracy and reliability of pinhole detection.

[0058] During the pulling process, the distance between the first slider 14 and the second slider 15 continues to shorten, meaning that the compression of the cylindrical spring 23 and the clamping force on the aluminum foil continue to increase. The initial small clamping force can prevent the aluminum foil from being damaged or deformed due to sudden excessive force. As the pulling process progresses, the gradually increasing clamping force can better adapt to the changing clamping force requirements of the aluminum foil during elastic deformation, ensuring that the aluminum foil is uniformly stressed in the width direction (i.e., perpendicular to its direction of travel) and maintains a stable pulling state. This makes the tension distribution on the surface of the aluminum foil more uniform, reduces the generation of wrinkles and ripples, and avoids the aluminum foil from slipping or loosening due to insufficient clamping force. This provides a flatter and clearer detection surface for the image sensor 3, thereby improving the accuracy and reliability of pinhole detection.

[0059] Please refer to it again. Figure 2 , Figure 4 , Figure 5 , Figure 12 as well as Figure 13 The top plate 1 is further provided with two cleaning mechanisms on the side facing the aluminum foil travel direction. Each cleaning mechanism includes a first motor 19 movably mounted above the aluminum foil, a mounting base 20 located at the output end of the first motor 19, and a cleaning roller 22 rotatably mounted on the mounting base 20. The mounting base 20 also has a second motor 21 for driving the cleaning roller 22 to rotate. The top plate 1 has a lifting structure for driving the cleaning roller 22 to rise and fall. The lifting structure includes a second guide rail 24 located on the side of the frame 2, a vertical arm 17 slidably connected to the second guide rail 24, and a second cylinder 18 rotatably mounted on the top plate 1. The movable end of the second cylinder 18 is hinged to the vertical arm 17, and the first motor 19 is mounted on the vertical arm 17.

[0060] During operation, the first motor 19 drives the mounting base 20 to swing the cleaning roller 22 in the horizontal direction, and the second motor 21 drives the cleaning roller 22 to rotate. Thus, before the aluminum foil enters the detection area (i.e., below the image sensor 3, within the area covered by the acquired image), the cleaning roller 22 can remove dust and impurities from the surface of the aluminum foil, improving the clarity and accuracy of the detection image and providing a more reliable foundation for subsequent pinhole detection.

[0061] The second cylinder 18 can drive the vertical arm 17 to slide on the second guide rail 24, thereby changing the height of the cleaning roller 22. Specifically, when the cleaning roller 22 swings towards the outside of the aluminum foil, the cleaning roller 22 contacts the surface of the aluminum foil and uses its rotation to throw the ash impurities out of the aluminum foil. Before the cleaning roller 22 swings back, the second cylinder 18 will push the vertical arm 17 to rise, so that the cleaning roller 22 is raised, to prevent the cleaning roller 22 from bringing the impurities back to the aluminum foil during the swinging process.

[0062] Preferably, the side of the frame 2 is also provided with a dust collection device. The dust collection device is located on the side of the aluminum foil. During the cleaning process, the dust collection device is turned on, which can absorb and transfer the dust and impurities that are swept up in time, so as to avoid the problem of dust and impurities escaping.

[0063] It should be noted that, depending on the product's usage requirements, single-sided or double-sided inspection can be selected. The attached figure shows single-sided inspection. For double-sided inspection, an image sensor 3 and the cleaning mechanism can be added below the aluminum foil. This will not be elaborated further in this application.

[0064] As another embodiment of the present invention, a method for detecting surface defects of aluminum foil during unrolling is also proposed. Using the aforementioned detection device, a cleaning mechanism cleans the surface of the aluminum foil before it enters the detection area.

[0065] After the aluminum foil enters the detection area, the power mechanism drives the two horizontal arms 7 to move closer together, causing multiple clamping tentacles 5 to clamp the aluminum foil. Then, the aluminum foil is pulled perpendicular to the direction of travel, and the image sensor 3 acquires the first image. Subsequently, the repositioning structure drives the clamping plate 4 to move, changing the position of the multiple clamping tentacles 5 in the direction of travel of the aluminum foil. The aluminum foil is then clamped again and pulled a second time, and the image sensor 3 acquires the second image. The processor combines the first image and the second image to form a complete image of the aluminum foil surface, and then performs defect analysis.

[0066] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0067] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. An image analysis-based aluminum foil rewinding surface defect detection device, comprising a top plate and two frames respectively disposed on both sides of the top plate; Its features are, Also includes: An image sensor mounted on the top plate is used to acquire surface image information of the aluminum foil; Two sets of clamping and pulling units are respectively set on two frames, including two horizontal arms distributed vertically. A clamping plate is movably installed on the horizontal arm. Multiple clamping tentacles are equidistantly arranged on the clamping plate along the direction of aluminum foil travel. The two horizontal arms can be driven by two sets of power mechanisms on the frame to move towards each other, so that the clamping tentacles located above and below the aluminum foil can perform clamping actions on the side of the aluminum foil. During testing, the clamping and pulling unit pulls the side of the aluminum foil once and twice in succession. The image sensor acquires the first image and the second image respectively. After each pull ends and before the second pull, the clamping plate is moved by the displacement structure on the horizontal arm so that the position of the multiple clamping tentacles changes in the direction of aluminum foil travel. The frame is provided with a first guide rail, and the power mechanism includes two sets of sliding structures symmetrically arranged on the first guide rail. The two sets of sliding structures are respectively connected to the two cross arms. The two sets of sliding structures can be driven by a threaded drive unit installed on the frame to slide closer to or further away from each other on the first guide rail. The sliding structure includes a first slider and a second slider that are slidably fitted on the first guide rail. An elastic element is provided between the first slider and the second slider. The first slider is connected to the threaded drive element. A driven component is provided between the second slider and the cross arm. When the aluminum foil is clamped, the first slider and the second slider move relative to each other, and the driven component is triggered, causing the cross arm to move closer to the second slider. The elastic element includes a column disposed on the second slider and a cylindrical spring sleeved on the outer periphery of the column. The column passes through the first slider, and the first slider is slidably connected to the column. The two ends of the cylindrical spring are respectively connected to the first slider and the second slider. The driven component includes a guide arm and a telescopic arm fixed to the second slider and the cross arm respectively. The guide arm and the telescopic arm are slidably fitted together. A column is fixedly provided on the first slider by a support arm. A transmission plate is provided on the telescopic arm. The transmission plate is provided with a through groove adapted to the column. The column passes through the through groove and is slidably connected to the transmission plate. The through groove includes a vertical section and an inclined section connected together. When the threaded drive is activated, it can cause the two first sliders on the first guide rail to move closer to each other or further away from each other, so that the clamping hand can clamp the aluminum foil. After the column moves along the vertical section, the compression of the column spring is increased, so that the clamping tentacles have the clamping force to pull the aluminum foil. Then, after the column enters the inclined section, it will slide with the transmission plate. The transmission plate will give way, causing the telescopic arm to slide towards the second slider on the guide arm, so that the aluminum foil is pulled perpendicular to the direction of travel.

2. The aluminum foil rewinding surface defect detection device based on image analysis according to claim 1, characterized in that, The length direction of the horizontal arm is parallel to the direction of travel of the aluminum foil. The switching structure includes a movable arm that is slidably sleeved on the horizontal arm. The clamping plate is fixed to the movable arm. The movable arm can be driven to move by a pneumatic component provided on the horizontal arm so as to change the position of the plurality of clamping tentacles in the direction of travel of the aluminum foil.

3. The image analysis-based aluminum foil rewinding surface defect detection device according to claim 2, characterized in that, The pneumatic assembly includes an assembly arm fixedly mounted on the cross arm and a first cylinder rotatably mounted on the assembly arm, wherein the movable end of the first cylinder is hinged to the movable arm.

4. The image analysis-based aluminum foil rewinding surface defect detection device according to claim 1, characterized in that, The top plate is also provided with two sets of cleaning mechanisms on the side facing the direction of aluminum foil travel. The cleaning mechanism includes a first motor movably mounted above the aluminum foil, an assembly base located at the output end of the first motor, and a cleaning roller rotatably mounted on the assembly base. The assembly base is also provided with a second motor for driving the cleaning roller to rotate. The top plate is provided with a lifting structure for driving the cleaning roller to rise and fall.

5. The image analysis-based aluminum foil rewinding surface defect detection device according to claim 4, characterized in that, The lifting structure includes a second guide rail disposed on the side of the frame, a vertical arm slidably connected to the second guide rail, and a second cylinder rotatably mounted on the top plate. The movable end of the second cylinder is hinged to the vertical arm, and the first motor is mounted on the vertical arm.

6. A method for detecting surface defects in rolled aluminum foil, using the detection device as described in claim 1, characterized in that, Before the aluminum foil enters the inspection area, the cleaning unit cleans the surface of the aluminum foil; After the aluminum foil enters the detection area, the power mechanism drives the two horizontal arms to move closer together, causing multiple gripping tentacles to clamp the aluminum foil. Then, the aluminum foil is pulled perpendicular to the direction of travel, and the image sensor acquires the first image. Subsequently, the repositioning structure drives the clamping plate to move, changing the position of the multiple gripping tentacles in the direction of travel of the aluminum foil. The aluminum foil is then clamped again and pulled a second time, and the image sensor acquires the second image. The processor combines the first image and the second image to form a complete image of the aluminum foil surface, and then performs defect analysis.

Images