Aluminum foil back-rolling surface defect detection device and detection method based on image analysis

Abstract

The invention relates to the related technical field of aluminum foil detection, in particular to an aluminum foil back-roll surface defect detection device and method based on image analysis, the aluminum foil back-roll surface defect detection device based on image analysis comprises a top plate and two frame bodies arranged on the two sides of the top plate respectively, and further comprises an image sensor installed on the top plate, the camera is used for acquiring aluminum foil surface image information; the two groups of clamping traction units are respectively arranged on the two frame bodies and comprise two cross arms which are distributed up and down, clamping plates are movably arranged on the cross arms, and a plurality of clamping tentacles are equidistantly arranged on the clamping plates along the advancing direction of the aluminum foil; the clamping traction unit can clamp the side edge of the aluminum foil, then traction with proper force is carried out in the direction perpendicular to the advancing direction of the aluminum foil, elastic shrinkage of the aluminum foil in the width direction caused by traction force in the advancing direction in the back-rolling process is offset, the phenomena of stress concentration and surface unevenness caused by width change are reduced, and the yield of the aluminum foil is improved. And a more stable and clearer detection surface is provided for the image sensor.

Description

Technical Field

[0001] The present invention relates to the technical field related to aluminum foil detection, and in particular to an image analysis-based surface defect detection device and method for aluminum foil rewinding. Background Art

[0002] Aluminum foil is a thin sheet material made from aluminum. It is lightweight, flexible, and has excellent electrical and thermal conductivity, making it suitable for a wide range of applications. Pinholes are one of the most common defects in aluminum foil. These are tiny holes that appear on the foil surface. These holes are typically small in diameter and may be round or irregular in shape. The primary cause is inadequate cleaning of the foil during production, leading to the presence of impurities such as oil, sweat, and dust. These impurities generate gas during melting, which in turn forms pinholes. Pinholes reduce the barrier properties of the foil, weakening its moisture and gas resistance, and thus affecting its performance.

[0003] Therefore, surface defect detection is an essential process in aluminum foil production. Currently, this process involves intermittent rewinding, with image sensors capturing surface information during each pause to detect defects.

[0004] However, as the aluminum foil is rolled back, it is subject to a pulling force in its direction of travel (to ensure that the foil remains taut to a certain extent), which can easily lead to elastic contraction in the width direction of the foil, thereby easily causing 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 foil surface and light reflection. Therefore, existing detection methods, by setting image sensors directly above or below the aluminum foil, find it difficult for the image sensors to obtain stable and clear images due to these unfavorable factors, resulting in poor accuracy and reliability of defect detection. Summary of the Invention

[0005] The purpose of the present invention is to provide an aluminum foil rewind surface defect detection device and detection method based on image analysis to solve the problems raised in the above background technology.

[0006] To achieve the above object, the present invention provides the following technical solutions: The device for detecting surface defects of aluminum foil rewinding based on image analysis includes a top plate and two frames respectively arranged on both sides of the top plate, and further includes: An image sensor mounted on the top plate is used to obtain surface image information of the aluminum foil; Two sets of clamping and pulling units are respectively provided on two frames, including two upper and lower horizontal arms, each of which is provided with a clamping plate. The clamping plate is provided with a plurality of clamping tentacles at equal intervals along the direction of travel of the aluminum foil. The two horizontal arms can be driven by two sets of power mechanisms provided on the frame to move toward each other, so that the clamping tentacles located above and below the aluminum foil can perform a clamping action on the side of the aluminum foil; During detection, the clamping and pulling unit pulls the side of the aluminum foil once and twice in succession, and the image sensor obtains the first image and the second image respectively. After each pulling is completed and before the second pulling, the clamping plate will be driven by the transposition structure on the horizontal arm to move, so that the positions of multiple clamping tentacles in the direction of aluminum foil movement will change.

[0007] As a further solution of the present invention: the length direction of the cross arm is parallel to the traveling direction of the aluminum foil, the transposition structure includes a movable arm slidably mounted on the cross arm, the clamping plate is fixed to the movable arm, and the movable arm can be driven by a pneumatic component arranged on the cross arm to move, so that the positions of the multiple clamping tentacles in the traveling direction of the aluminum foil can be changed.

[0008] As a further solution 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, and the movable end of the first cylinder is hinged to the movable arm.

[0009] As a further solution of the present invention: a first guide rail is provided on the frame, and the power mechanism includes two groups of sliding structures symmetrically arranged on the first guide rail, the two groups of sliding structures are respectively connected to the two cross arms, and the two groups of sliding structures can be driven by a threaded driving member installed on the frame to slide towards or away from each other on the first guide rail.

[0010] As a further solution of the present invention: the sliding structure includes a first slider and a second slider slidingly engaged on the first guide rail, an elastic member is provided between the first slider and the second slider, the first slider is connected to the threaded driving member, and 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.

[0011] As a further solution of the present invention: the elastic member includes a column arranged on the second slider and a cylindrical spring sleeved on the outer circumference 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.

[0012] As a further solution of the present invention: the driven assembly includes a guide arm and a telescopic arm respectively fixed to the second slider and the cross arm, the guide arm and the telescopic arm are slidably fitted together, a column is fixed on the first slider through a support arm, a transmission plate is provided on the telescopic arm, a through groove adapted to the column is provided on the transmission plate, the column passes through the through groove and is slidably connected to the transmission plate, and the through groove includes a connected vertical section and an inclined section.

[0013] As a further solution of the present invention: two sets of cleaning mechanisms are also provided on the side of the top plate facing the direction of travel of the aluminum foil, and the cleaning mechanisms include a first motor movably arranged above the aluminum foil, an assembly seat arranged at the output end of the first motor, and a cleaning roller rotatably installed on the assembly seat, and 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.

[0014] As a further solution of the present invention: the lifting structure includes a second guide rail arranged on the side of the frame, a vertical arm slidingly connected to the second guide rail, and a second cylinder rotatably installed on the top plate, the movable end of the second cylinder is hinged to the vertical arm, and the first motor is installed on the vertical arm.

[0015] As a further solution of the present invention: a method for detecting surface defects of aluminum foil rewinding, using the above-mentioned detection device, a cleaning mechanism cleans the surface of the aluminum foil before the aluminum foil enters the detection area; After the aluminum foil enters the detection area, the power mechanism drives the two cross arms to approach each other, so that multiple clamping tentacles clamp the aluminum foil, and then pull the aluminum foil perpendicular to the direction of travel of the aluminum foil. The image sensor obtains the first image. Subsequently, the transposition structure drives the splint to move, changing the position of multiple clamping tentacles in the direction of travel of the aluminum foil, and then clamps the aluminum foil again and pulls it a second time. The image sensor obtains the second image. The processor synthesizes the first image and the second image to form a complete image of the aluminum foil surface, and then performs defect analysis.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The present application provides a set of clamping and pulling units on both sides of the aluminum foil. The clamping and pulling units clamp the side edges of the aluminum foil in advance and then pull the foil with appropriate force perpendicular to the direction of travel of the aluminum foil, effectively offsetting the elastic contraction of the aluminum foil in the width direction caused by the pulling force in the travel direction during the rewinding 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, avoiding pinholes that may be difficult to accurately identify due to factors such as wrinkles on the aluminum foil surface and light reflection, thereby improving the accuracy and reliability of pinhole detection. Secondly, each detection includes a first pull and a second pull, and the image sensor acquires a first image and a second image respectively. Specifically, after the first pull is completed and before the second pull, the clamping plate is driven by the transposition structure provided on the cross arm to move, so that the positions of the multiple clamping tentacles in the direction of travel of the aluminum foil are changed. The multiple clamping tentacles are offset from their previous positions. As a result, the position of the aluminum foil being clamped changes, realizing a transposition clamping function, avoiding the problem of occlusion caused by the fixed clamping position, which leads to incomplete images of the aluminum foil surface acquired by the image sensor. In addition, when pulling, the distance between the first slider and the second slider continues to decrease, 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. As the pulling progresses, the force gradually increases, so that the aluminum foil is evenly stressed in the width direction, maintaining stable pulling and uniform tension distribution, suppressing wrinkles and ripples, preventing slack and slippage, providing a flat and clear detection surface for the image sensor, and improving the accuracy and reliability of pinhole detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is an axonometric diagram of an embodiment of a device for detecting surface defects of aluminum foil rewinding based on image analysis.

[0018] Figure 2 The figure is a schematic structural diagram of an embodiment of a device for detecting surface defects of aluminum foil rewinding based on image analysis.

[0019] Figure 3 This is a structural schematic diagram from another angle of an embodiment of an aluminum foil rewind surface defect detection device based on image analysis.

[0020] Figure 4 The present invention is a structural schematic diagram of another angle of an embodiment of a device for detecting surface defects of aluminum foil rewinding based on image analysis.

[0021] Figure 5 This is a front view of an embodiment of a device for detecting surface defects of aluminum foil rewinding based on image analysis.

[0022] Figure 6 for Figure 4 A magnified view of the structure at point A in the middle.

[0023] Figure 7 This is a schematic diagram of the connection status of the top plate and the frame in one embodiment of an aluminum foil rewind surface defect detection device based on image analysis.

[0024] Figure 8 for Figure 7 Schematic diagram of the structure from another angle.

[0025] Figure 9 This is a structural schematic diagram of the clamping and pulling unit in an embodiment of an aluminum foil rewind surface defect detection device based on image analysis.

[0026] Figure 10 This is a structural schematic diagram of another angle of the clamping and pulling unit in one embodiment of an aluminum foil rewind surface defect detection device based on image analysis.

[0027] Figure 11 This is an exploded diagram of the structure of the clamping and pulling unit in one embodiment of the aluminum foil rewind surface defect detection device based on image analysis.

[0028] Figure 12 This is a schematic structural diagram of the cleaning mechanism in one embodiment of an aluminum foil rewind surface defect detection device based on image analysis.

[0029] Figure 13 This is a top view of the cleaning mechanism in one embodiment of an aluminum foil rewind surface defect detection device based on image analysis.

[0030] In the figure: 1. top plate; 2. frame; 3. image sensor; 4. clamping plate; 5. clamping tentacle; 501. rubber gasket; 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 seat; 21. second motor; 22. cleaning roller; 23. cylindrical spring; 24. second guide rail; 25. support arm; 26. column. DETAILED DESCRIPTION

[0031] The following will clearly and completely describe the technical solutions in the embodiments of the present invention 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 making creative efforts are within the scope of protection of the present invention.

[0032] In addition, when an element in the present invention is referred to as being "disposed on" or "positioned on" another element, it may be directly on the other element or there may be an intermediate element. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only embodiment.

[0033] See also Figures 1-13 In an embodiment of the present invention, an image analysis-based surface defect detection device for aluminum foil rewinding includes a top plate 1 and two frames 2 respectively arranged on both sides of the top plate 1, and further includes: The image sensor 3 mounted on the top plate 1 is used to obtain surface image information of the aluminum foil; Two sets of clamping and pulling units are respectively provided on the two frames 2, including two upper and lower horizontal arms 7, on which a clamping plate 4 is movably provided, and on which a plurality of clamping tentacles 5 are equidistantly provided along the direction of travel of the aluminum foil. The two horizontal arms 7 can be driven by two sets of power mechanisms provided on the frames 2 to move toward each other, so that the clamping tentacles 5 located above and below the aluminum foil can perform a clamping action on the side of the aluminum foil; During detection, the clamping and pulling unit pulls the side of the aluminum foil once and twice in succession, and the image sensor 3 obtains the first image and the second image respectively. After each pulling is completed and before the second pulling, the clamping plate 4 will be driven by the transposition structure provided on the cross arm 7 to move, so that the positions of the multiple clamping tentacles 5 in the direction of travel of the aluminum foil are changed.

[0034] It should be noted that during actual rewinding, corresponding guide wheels need to be set on both sides of the device to guide the aluminum foil. It is necessary to ensure that the aluminum foil on the path passing through this device always remains straight to facilitate smooth detection.

[0035] It should be noted that the detection principle of the image sensor 3 is as follows: when light is irradiated on the surface of the aluminum foil, the intact surface of the aluminum foil reflects or absorbs the light, while the light at the pinhole penetrates the aluminum foil, forming a point or area with a grayscale different from the surrounding area on the image sensor 3. The sensor captures this difference and analyzes it through an image processing algorithm to identify the pinhole defect. In conjunction with the present application, the clamping and pulling unit will clamp the side of the aluminum foil in advance, and then pull it with appropriate force perpendicular to the traveling direction of the aluminum foil, effectively offsetting the elastic contraction of the aluminum foil in the width direction caused by the pulling force in the traveling direction during the rewinding process, thereby allowing the aluminum foil to maintain 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 3, avoiding pinholes that may be difficult to accurately identify due to factors such as wrinkles on the aluminum foil surface and light reflection, thereby improving the accuracy and reliability of pinhole detection; Secondly, every time a pulling is completed and before a second pulling is performed, the clamping plate 4 is driven by the transposition structure provided on the cross arm 7 to move, so that the positions of the multiple clamping tentacles 5 in the direction of travel of the aluminum foil are changed. The multiple clamping tentacles 5 are staggered from their previous positions. As a result, the position where the aluminum foil is clamped is changed, thereby avoiding the problem of occlusion caused by the fixed clamping position, which would result in an incomplete image of the aluminum foil surface obtained by the image sensor 3. For the primary image and the secondary image acquired by the image sensor 3 , the processor will synthesize the primary image and the secondary image during analysis to form a complete aluminum foil surface image, so as to fully analyze the aluminum foil surface information.

[0036] Please refer again Figure 10 and Figure 11 The length of the cross arm 7 is parallel to the direction of travel of the aluminum foil. The displacement structure includes a movable arm 6 slidably mounted on the cross arm 7. The clamping plate 4 is fixed to the movable arm 6. The movable arm 6 can be driven by a pneumatic assembly on the cross arm 7 to move, thereby changing the position of the multiple clamping tentacles 5 in the direction of travel of the aluminum foil. The pneumatic assembly includes an assembly arm 8 fixedly mounted on the cross 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.

[0037] When inspecting a certain position of the aluminum foil, before performing the secondary clamping and pulling, the movable end of the first cylinder 9 moves, which will drive the movable arm 6 to slide on the cross arm 7. As a result, the positions of the multiple clamping tentacles 5 in the direction of travel of the aluminum foil will change, and each clamping tentacle 5 will be staggered from its previous position, so that the part of the aluminum foil surface that was clamped during the first clamping and pulling can be exposed, ensuring the integrity of the inspection.

[0038] It should be noted that during the detection process, the degree of pulling of the aluminum foil by the clamping and pulling unit must be strictly controlled to ensure that the strain generated by the aluminum foil is within its elastic limit. Specifically, experiments can be conducted in advance to determine the maximum strain value within the elastic range of aluminum foils of different thicknesses and materials. The stretching amount can be set based on this. This can not only avoid damage to the aluminum foil caused by excessive stretching, but also improve the detection rate of pinholes to a certain extent. A softer and more uniform clamping material and method is used to reduce local stress concentration. To this end, each clamping tentacle 5 is provided with a rubber gasket 501 on the side facing the aluminum foil. The rubber gasket 501 is used as the clamping surface to increase the clamping area and make the stress distribution more uniform.

[0039] Please refer 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 driving member installed on the frame 2 to slide toward or away from each other on the first guide rail 16. The sliding structure includes a first slider 14 and a second slider 15 that are slidably engaged with the first guide rail 16. An elastic member is provided between the first slider 14 and the second slider 15. The first slider 14 is connected to the threaded driving 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 toward the second slider 15. The elastic member includes a column 13 disposed on the second slider 15 and a cylindrical spring 23 sleeved around 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 ends of the cylindrical spring 23 are respectively connected to the first slider 14 and the second slider 15. The driven assembly includes a guide arm 11 and a telescopic arm 12, which are respectively fixed to the second slider 15 and the cross arm 7. The guide arm 11 slides and fits with the telescopic arm 12. A column 26 is fixed to the first slider 14 via a support arm 25. The telescopic arm 12 is provided with a transmission plate 10. The transmission plate 10 has a through slot adapted to the column 26. The column 26 passes through the through slot and is slidably connected to the transmission plate 10. The through slot includes a connected vertical section 1001 and an inclined section 1002.

[0040] Specifically, the threaded drive component includes a bidirectional screw (not numbered in the figure) rotatably mounted on the frame 2 and two threaded sleeves symmetrically sleeved on the bidirectional screw. The two threaded sleeves are respectively fixedly connected to the two first sliders 14 located on the first guide rail 16. When the bidirectional screw rotates, the two threaded sleeves are threadedly engaged with the bidirectional screw, so that the two first sliders 14 on the first guide rail 16 can be moved closer to or away from each other, thereby realizing the clamping function of the clamping tentacles 5 on the aluminum foil. This driving method through threaded engagement has high driving accuracy and good stability, thereby being able to effectively control the pulling accuracy.

[0041] The two first sliders 14 on the first guide rail 16 move toward each other. Before the clamping tentacles 5 come into contact with the side of the aluminum foil, the second slider 15 moves along with the first slider 14. After the clamping tentacles 5 come into contact with the side of the aluminum foil, the first slider 14 and the second slider 15 begin to move relative to each other, gradually approaching the second slider 15. During this process, the cylindrical spring 23 is compressed, and the cylinder 26 slides along the vertical section 1001 and the inclined section 1002 in sequence. Specifically, after the column 26 moves along the vertical section 1001, the compression amount of the cylindrical spring 23 is increased to a sufficiently large amount, so that the clamping tentacle 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 gives way, driving the telescopic arm 12 to slide on the guide arm 11 toward the second slider 15. Then, the telescopic arm 12 drives the clamping plate 4 to move perpendicular to the direction of travel of the aluminum foil through the cross arm 7 and the movable arm 6. As a result, the aluminum foil is pulled perpendicular to the direction of travel, thereby improving the accuracy and reliability of pinhole detection. In the pulling process, the distance between the first slider 14 and the second slider 15 is still shortening, that is, the compression of the cylindrical spring 23 and the clamping force on the aluminum foil continue to increase. The initial smaller clamping force can prevent the aluminum foil from being damaged or locally deformed due to sudden excessive force. As the pulling process progresses, the gradually increasing clamping force can better adapt to the changes in the aluminum foil's demand for clamping force during elastic deformation, ensuring that the aluminum foil is uniformly stressed in the width direction (that is, perpendicular to its travel direction) and maintains a stable pulling state, making the tension distribution on the aluminum foil surface more uniform, reducing the generation of wrinkles and ripples, and avoiding the aluminum foil from slipping or relaxing due to insufficient clamping force, providing a smoother and clearer detection surface for the image sensor 3, thereby improving the accuracy and reliability of pinhole detection.

[0042] Please refer again Figure 2 、 Figure 4 、 Figure 5 、 Figure 12 as well as Figure 13The top plate 1 is also provided with two cleaning mechanisms on the side facing the direction of aluminum foil travel. The cleaning mechanisms include a first motor 19 movably disposed above the aluminum foil, an assembly seat 20 disposed at the output end of the first motor 19, and a cleaning roller 22 rotatably mounted on the assembly seat 20. The assembly seat 20 is also provided with a second motor 21 for driving the cleaning roller 22 to rotate. The top plate 1 is provided with a lifting structure for driving the cleaning roller 22 to rise and fall. The lifting structure includes a second guide rail 24 disposed 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.

[0043] During operation, the first motor 19 drives the assembly base 20 to drive the cleaning roller 22 to swing horizontally, 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 and within the range covered by the captured image), the cleaning roller 22 can sweep away dust and impurities on the surface of the aluminum foil, thereby improving the clarity and accuracy of the detection image and providing a more reliable basis for subsequent pinhole detection. 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 toward the outside of the aluminum foil, the cleaning roller 22 contacts the surface of the aluminum foil and uses its own rotation to throw ash and impurities to the outside of the aluminum foil. Before the cleaning roller 22 swings back, the second cylinder 18 will push the vertical arm 17 upward to lift the cleaning roller 22, so as to prevent the cleaning roller 22 from bringing impurities back onto the aluminum foil during the swinging process. Preferably, a dust suction device is further provided on the side of the frame 2, and the dust suction device is located on the side of the aluminum foil. During the cleaning process, the dust suction device is turned on to absorb and transfer the dust and impurities swept down in time to avoid the problem of dust and impurities escaping.

[0044] It should be pointed out that, depending on the usage requirements of the product, single-sided detection or double-sided detection can be selected. The figure shows single-sided detection. For double-sided detection, an image sensor 3 and the cleaning mechanism can be added under the aluminum foil. This application will not go into details about this.

[0045] As another embodiment of the present invention, a method for detecting surface defects of aluminum foil rewinding is also proposed. Using the above-mentioned detection device, a cleaning mechanism cleans the surface of the aluminum foil before the aluminum foil enters the detection area. After the aluminum foil enters the detection area, the power mechanism drives the two cross arms 7 to approach each other, so that the multiple clamping tentacles 5 clamp the aluminum foil, and then pull the aluminum foil perpendicular to the direction of travel of the aluminum foil. The image sensor 3 obtains the first image. Subsequently, the transposition 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, and then clamps the aluminum foil again and pulls it a second time. The image sensor 3 obtains the second image. The processor synthesizes the first image and the second image to form a complete surface image of the aluminum foil, and then performs defect analysis.

[0046] 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 embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

[0047] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. An image analysis-based device for detecting surface defects of aluminum foil rewinds, comprising a top plate and two frames disposed on either side of the top plate; It is characterized by: Also includes: An image sensor mounted on the top plate is used to obtain surface image information of the aluminum foil; Two sets of clamping and pulling units are respectively provided on two frames, including two upper and lower horizontal arms, each of which is provided with a clamping plate. The clamping plate is provided with a plurality of clamping tentacles at equal intervals along the direction of travel of the aluminum foil. The two horizontal arms can be driven by two sets of power mechanisms provided on the frame to move toward each other, so that the clamping tentacles located above and below the aluminum foil can perform a clamping action on the side of the aluminum foil; During detection, the clamping and pulling unit pulls the side of the aluminum foil once and twice in succession, and the image sensor obtains the first image and the second image respectively. After each pulling is completed and before the second pulling, the clamping plate will be driven by the transposition structure on the horizontal arm to move, so that the positions of multiple clamping tentacles in the direction of aluminum foil movement will change.

2. The device for detecting surface defects of aluminum foil rewinding based on image analysis according to claim 1 is characterized in that: The length direction of the cross arm is parallel to the direction of travel of the aluminum foil. The transposition structure includes a movable arm slidably mounted on the cross arm. The clamping plate is fixed to the movable arm. The movable arm can be driven by a pneumatic component arranged on the cross arm to move, so that the positions of the multiple clamping tentacles in the direction of travel of the aluminum foil can be changed.

3. The device for detecting surface defects of aluminum foil rewinding based on image analysis 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 device for detecting surface defects of aluminum foil rewinding based on image analysis according to claim 1, characterized in that: A first guide rail is provided on the frame, and the power mechanism includes two groups of sliding structures symmetrically arranged on the first guide rail. The two groups of sliding structures are respectively connected to the two cross arms. The two groups of sliding structures can be driven by a threaded driving member installed on the frame to slide towards or away from each other on the first guide rail.

5. The device for detecting surface defects of aluminum foil rewinding based on image analysis according to claim 4 is characterized in that: The sliding structure includes a first slider and a second slider slidably engaged on the first guide rail, an elastic member is provided between the first slider and the second slider, the first slider is connected to the threaded driving member, and 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.

6. The device for detecting surface defects of aluminum foil rewinding based on image analysis according to claim 5, characterized in that: The elastic member includes a column arranged on the second slider and a cylindrical spring sleeved on the outer circumference 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.

7. The device for detecting surface defects of aluminum foil rewinding based on image analysis according to claim 5, characterized in that: The driven assembly includes a guide arm and a telescopic arm respectively fixed to the second slider and the cross arm, the guide arm and the telescopic arm are slidably fitted together, a column is fixed on the first slider through a support arm, a transmission plate is provided on the telescopic arm, a through groove adapted to the column is provided on the transmission plate, the column passes through the through groove and is slidably connected to the transmission plate, and the through groove includes a connected vertical section and an inclined section.

8. The device for detecting surface defects of aluminum foil rewinding based on image analysis according to claim 1, characterized in that: Two sets of cleaning mechanisms are also provided on the side of the top plate facing the direction of travel of the aluminum foil. The cleaning mechanisms include a first motor movably arranged above the aluminum foil, an assembly seat arranged 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.

9. The device for detecting surface defects of aluminum foil rewinding based on image analysis according to claim 8, characterized in that: The lifting structure includes a second guide rail arranged 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 installed on the vertical arm.

10. A method for detecting surface defects of aluminum foil rewinding, using the detection device according to claim 1, characterized in that: Before the aluminum foil enters the detection area, the cleaning mechanism cleans the surface of the aluminum foil; After the aluminum foil enters the detection area, the power mechanism drives the two cross arms to approach each other, so that multiple clamping tentacles clamp the aluminum foil, and then pull the aluminum foil perpendicular to the direction of travel of the aluminum foil. The image sensor obtains the first image. Subsequently, the transposition structure drives the splint to move, changing the position of multiple clamping tentacles in the direction of travel of the aluminum foil, and then clamps the aluminum foil again and pulls it a second time. The image sensor obtains the second image. The processor synthesizes the first image and the second image to form a complete image of the aluminum foil surface, and then performs defect analysis.

Images