Machine vision-based defect detection device for plastic products

Abstract

This invention relates to the field of industrial vision inspection technology, specifically to a machine vision-based defect detection device for plastic products. The device includes a frame on which an industrial vision inspection device is mounted, a surrounding conveyor system, and a vertical rod fixed to the frame, with a rack at the top of the vertical rod. The surrounding conveyor system is equipped with several clamping components for clamping plastic bottles. Each clamping component consists of a flipping structure and a clamping structure, and each clamping structure consists of a triggering part and a clamping part. Each clamping part includes two clamping members arranged on the outer periphery of a clamping base. This invention achieves omnidirectional defect detection by dynamically rotating the plastic bottle and taking multiple photos using a single CDD camera, avoiding the high cost and complex calibration problems of multi-camera layouts, simplifying the hardware structure, and reducing equipment investment and maintenance costs.

Description

Technical Field

[0001] This invention relates to the field of industrial visual inspection technology, and more specifically, to a machine vision-based defect detection device for plastic products. Background Technology

[0002] The plastic bottle defect detection device based on industrial vision inspection technology is an automated inspection system that integrates image acquisition, processing and intelligent analysis. It achieves efficient and accurate identification of surface and structural defects in the plastic bottle production process through machine vision technology.

[0003] A search revealed that Chinese patent CN222994347U discloses an automatic visual inspection device for defects in plastic bottles. The device includes a worktable with a conveyor belt inside. Fixed seats are fixedly connected to both the front and rear ends of the worktable, and a mounting frame is rotatably connected to the top of each fixed seat. The mounting frame is rotatably connected to both the conveyor belt and the worktable. A handle is fixedly connected to the top of the mounting frame, and guide wheels are hinged inside the mounting frame. A support is in contact with the top of the worktable. This design utilizes the conveyor belt to transport plastic bottles. When the plastic bottle passes a CDD camera, the CDD camera can capture an image of the plastic bottle, enabling automatic visual inspection of defects. A motor's output can drive a screw to rotate, causing the support to move vertically. This allows for easy adjustment of the shooting height and improves applicability. However, in practical use, the above design still has the following shortcomings:

[0004] To ensure comprehensive industrial inspection of plastic bottles, the aforementioned device is equipped with at least three CCD cameras for inspection. While deploying at least three CCD cameras to achieve comprehensive inspection of plastic bottles improves accuracy, it also presents several drawbacks: hardware costs increase significantly with the number of cameras, requiring the simultaneous configuration of multiple light sources, lenses, and image acquisition cards, resulting in high initial investment and subsequent maintenance costs; multi-camera collaboration requires resolving spatial layout conflicts, complex optical path designs are prone to occlusion or reflection interference, and precise calibration of each camera parameter is necessary to ensure image stitching consistency, increasing the difficulty of system integration; parallel processing of multi-channel data places higher demands on computing resources, potentially requiring server upgrades or the adoption of a distributed architecture, further increasing equipment costs and energy consumption.

[0005] Based on this, the present invention discloses a defect detection device for plastic products based on machine vision. Summary of the Invention

[0006] To address the problem mentioned in the background art that while multi-CCD cameras improve accuracy in omnidirectional inspection, they also significantly reduce overall economic efficiency and maintainability due to soaring hardware costs, complex optical path design, high computational resource consumption, and decreased system stability, this invention provides a machine vision-based defect detection device for plastic products. The device includes a frame on which industrial vision inspection equipment is mounted, a surround conveyor system is mounted on the frame, a vertical rod is fixed to the frame, and a rack is fixed to the top of the vertical rod.

[0007] The surrounding conveying device is provided with several clamping components for clamping plastic bottles. Each clamping component consists of a flipping structure and a clamping structure. Each clamping structure consists of a triggering part and a clamping part. The clamping part includes two clamping members, both of which are arranged on the outer peripheral surface of the clamping seat.

[0008] The triggering part includes a clamping seat with a cavity inside. A sliding plug is slidably connected in the cavity. A top rod is fixed on the sliding plug, and the sliding plug and the cavity are connected by a spring. A slot is opened on the side of the clamping seat, and an air supply pipe is arranged in the slot. One end of the air supply pipe is connected to the cavity. An opening is opened at the top of the clamping seat and is connected to the cavity.

[0009] This technical solution uses a clamping part to clamp the plastic bottle, which can realize the automatic flipping, rotation and rejection of the plastic bottle;

[0010] As a further improvement to this technical solution, the flipping structure includes a mounting frame, which is fixed on the annular conveyor belt of the wraparound conveyor. A first servo motor is mounted on the mounting frame, and a swing frame is fixed on the output shaft of the first servo motor. The swing frame has a hole, and a rotating shaft is rotatably mounted in the hole. A rotating frame is fixed at one end of the rotating shaft, and a gear is fixed at the other end. Both the swing frame and the rotating frame are U-shaped structures, and the clamping seat is fixed on the rotating frame.

[0011] Based on this, in order to allow the plastic bottle to rotate during the inspection process, this solution uses a first servo motor to drive the rotating frame to rotate, thereby causing the plastic bottle to rotate.

[0012] As a further improvement to this technical solution, the triggering part further includes an elastic bladder and a movable block. The movable block is placed above the clamping seat and is positioned directly opposite the opening. One end of the elastic bladder is connected to the clamping seat, and the other end is connected to the movable block.

[0013] In another approach, a movable block is used as the driving mechanism to achieve automatic clamping of plastic bottles.

[0014] As a further improvement to this technical solution, each clamping component includes two side plates, both of which are fixed to the outer peripheral surface of the clamping seat and are arranged facing each other. A slidable magnetic slide plate is provided between the two side plates. The magnetic slide plate is connected to the clamping seat by a tension spring. Limiting openings are provided on both side plates. Two limiting blocks are fixed on the magnetic slide plate and slide in the two limiting openings respectively. A clamping strip is adsorbed on the magnetic slide plate. The clamping strip is composed of a clamping part and a driving part. The driving part is fixed to the top of the clamping part and has an inclined surface. The clamping part is used to abut against the mouth of the plastic bottle.

[0015] To ensure the stability of the magnetic slide's movement, this solution utilizes two limiting ports and two limiting blocks to provide limiting.

[0016] As a further improvement to this technical solution, the bottom surface of the clamping seat is provided with a first vent hole, and the bottom surface of the clamping seat is provided with a rotatable blocking plate, which is rotatably connected to the clamping seat through a hinge. The blocking plate is positioned directly opposite the first vent hole, and a torsion spring is provided on the hinge. The outer peripheral surface of the clamping seat is provided with a second vent hole, and a movable blocking ring is fitted on the outer peripheral surface of the clamping seat. A limiting protrusion is also fixed on the outer peripheral surface of the clamping seat, which provides a limit for the blocking ring. When the blocking ring falls on the limiting protrusion, the blocking ring is positioned directly opposite the second vent hole.

[0017] The outer peripheral surface of the clamping seat is fixed with two limiting lips, which together provide constraint for the plastic bottle. Each of the two limiting lips is provided with a pulling part.

[0018] As a further improvement to this technical solution, when gas is discharged through the first exhaust port, the device performs a rejection action for unqualified plastic bottles, and when gas is discharged through the second exhaust port, the device performs a collection action for qualified plastic bottles.

[0019] As a further improvement to this technical solution, the pulling part includes a second servo motor, which is mounted on the limiting lip. An eccentric wheel is fixed to the output shaft of the second servo motor. A fixing rod is fixed to the side of the eccentric wheel, and the fixing rod is located at the edge of the eccentric wheel. A rotating ring is rotatably sleeved on the fixing rod, and a pull rope is connected to the rotating ring. Of the two pull ropes, one pull rope is connected to the blocking plate, and the other pull rope is connected to the blocking ring.

[0020] As a further improvement to this technical solution, an anti-slip pad is adhered to the side of the clamping part.

[0021] As a further improvement to this technical solution, the top rod is positioned directly opposite the opening.

[0022] As a further improvement to this technical solution, both the magnetic sliding plate and the clamping bar are made of magnetic materials.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0024] 1. By dynamically rotating the plastic bottle and taking multiple photos with a single CDD camera, comprehensive defect detection is achieved, avoiding the high cost and complex calibration issues of multi-camera layouts, simplifying the hardware structure, significantly improving detection efficiency, and reducing equipment investment and maintenance costs.

[0025] 2. The device integrates automated clamping, flipping, rotating and defective product rejection functions. During the inspection process, the plastic bottles can automatically adjust their posture and complete the inspection. Qualified products and defective products are automatically classified and collected, reducing manual intervention and improving the automation level of the production line.

[0026] 3. Utilizing gas control ensures rapid and precise action response, enabling quick activation and reset of the clamping structure, rejection of defective products, and collection of qualified products. This significantly improves testing efficiency. Using gas as a power source avoids complex mechanical transmission structures, resulting in a simpler overall device structure, reducing the probability of equipment failure and maintenance costs. The gas control method offers high flexibility, allowing for adjustments to parameters such as gas pressure and flow rate based on different specifications of plastic bottles and actual production needs. This enables stable and reliable clamping of various plastic bottles, precise rejection of defective products, and efficient collection of qualified products. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the overall structure of the present invention. Figure 1 ;

[0028] Figure 2 for Figure 1 Enlarged view of the structure at point A;

[0029] Figure 3 This is a schematic diagram of the overall structure of the present invention. Figure 2 ;

[0030] Figure 4 Schematic diagram of the clamping assembly Figure 1 ;

[0031] Figure 5 Schematic diagram of the clamping assembly Figure 2 ;

[0032] Figure 6 for Figure 5 Enlarged view of the structure at point B;

[0033] Figure 7 Schematic diagram of the clamping assembly Figure 3 ;

[0034] Figure 8 for Figure 7 Enlarged view of the structure at point C;

[0035] Figure 9 This is a cross-sectional view of the clamping component;

[0036] Figure 10 A diagram showing the state of the clamping component when it is holding a plastic bottle.

[0037] Figure 11 This is a schematic diagram of the rotation of a plastic bottle.

[0038] The meanings of the labels in the diagram are as follows:

[0039] 11. Frame; 111. Vertical rod; 112. Rack; 12. Industrial vision inspection equipment; 13. Circular conveyor; 21. Mounting frame; 22. First servo motor; 23. Swing frame; 24. Rotating frame; 25. Rotating shaft; 26. Gear; 31. Clamping seat; 311. Limiting lip; 312. First vent; 3121. Blocking plate; 313. Second vent; 3131. Blocking ring; 3132. Limiting protrusion; 314. 315. Opening; 316. Groove; 32. Air supply pipe; 33. Cavity; 34. Sliding plug; 35. Top rod; 36. Spring; 47. Elastic bladder; 48. Movable block; 59. Side plate; 50. Magnetic sliding plate; 51. Limiting port; 52. Limiting block; 53. Clamping part; 54. Drive part; 555. Anti-slip pad; 556. Tension spring; 67. Second servo motor; 68. Eccentric wheel; 69. Fixed rod; 60. Rotating ring; 61. Pull rope. Detailed Implementation

[0040] 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.

[0041] While existing industrial vision inspection devices improve accuracy by using multiple CCD cameras to achieve omnidirectional inspection, their overall economic efficiency and maintainability are significantly reduced due to soaring hardware costs, complex optical path design, high computational resource consumption, and decreased system stability.

[0042] Therefore, this invention provides a machine vision-based defect detection device for plastic products, see [link to relevant documentation]. Figure 1As shown, it includes a frame 11, on which an industrial vision inspection device 12 is installed for industrial vision inspection of plastic bottles. The industrial vision inspection device 12 uses a CDD camera to quickly capture surface or internal images of the target object. Subsequently, the image processing unit preprocesses the raw data (such as noise reduction and contrast enhancement), and then identifies key information (such as size, shape, and defect location) through feature extraction algorithms. Finally, the intelligent analysis module compares and judges the data with preset standards. The specific working principle of this device is existing technology and will not be described in detail here. A surround conveyor 13 is installed on the frame 11 for conveying plastic bottles. The specific structure and working principle of this conveyor are existing technology and will not be described in detail here. During the transportation of plastic bottles, the surround conveyor 13 will pass directly under the industrial vision inspection device 12 one by one, and the industrial vision inspection device 12 will perform visual inspection and identification on the plastic bottles.

[0043] See Figures 4-9 As shown, the surrounding conveyor 13 is equipped with several clamping components for clamping plastic bottles. Each clamping component consists of a flipping structure and a clamping structure. Each clamping structure consists of a triggering part, a clamping part 551, and two pulling parts.

[0044] The flipping structure includes a mounting frame 21, which is fixed on the annular conveyor belt of the wraparound conveyor 13. A first servo motor 22 is mounted on the mounting frame 21. A swing frame 23 is fixed on the output shaft of the first servo motor 22. A hole is opened on the swing frame 23, and a rotating shaft 25 is rotatably mounted in the hole. A rotating frame 24 is fixed at one end of the rotating shaft 25, and a gear 26 is fixed at the other end. Both the swing frame 23 and the rotating frame 24 are U-shaped. The first servo motor 22 can drive the swing frame 23 to rotate, and the rotating frame 24 can rotate around the rotating shaft 25. A vertical rod 111 is fixed on the frame 11, and a rack 112 is fixed at the top of the vertical rod 111. The rack 112 is set in the horizontal direction. When the wraparound conveyor 13 is running, several mounting frames 21 move accordingly.

[0045] Initially, the U-shaped openings of both the swing frame 23 and the rotating frame 24 face downwards. At this point, the plastic bottle is clamped and held vertically. Before the mounting frame 21 passes the inspection area of ​​the industrial vision inspection equipment 12, the first servo motor 22 runs, driving the swing frame 23 to rotate until it rotates 90°. As the swing frame 23 rotates, the plastic bottle on it rotates accordingly, eventually reaching a horizontal position. Figure 11As shown, during the process of the plastic bottle rotating from a vertical to a horizontal position, as the mounting frame 21 passes through the detection area of ​​the industrial vision inspection equipment 12, the gear 26 meshes with the rack 112 and rotates under the action of the rack 112. The rotation of the gear 26 drives the rotating shaft 25 to rotate, causing the rotating frame 24 and the plastic bottle to rotate accordingly. In summary, before entering the detection area of ​​the industrial vision inspection equipment 12, the plastic bottle first rotates from a vertical to a horizontal position, then maintains a horizontal posture as it enters the detection area, slowly rotating during the inspection process. Simultaneously, the industrial vision inspection equipment detects the plastic bottle's rotation. The CDD camera in the inspection device 12 takes multiple pictures of the plastic bottle to obtain inspection samples from different angles, thereby performing all-round inspection of the plastic bottle. Compared with the traditional inspection method, this dynamic inspection method only requires one CDD camera to achieve all-round inspection of the plastic bottle, eliminating the need to set up multiple CDD cameras. This avoids the high cost and complex calibration problems caused by multi-camera layout, and expands the detection coverage of a single camera through dynamic rotation. Ultimately, it achieves all-round defect identification in a simplified hardware structure, significantly improving inspection efficiency and reducing equipment investment and maintenance costs.

[0046] See Figure 9 As shown, the triggering part includes a clamping seat 31, which is fixed on the rotating frame 24 so that the clamping seat 31 can rotate with the rotating frame 24. The clamping seat 31 has a cavity 32 inside, and a sliding plug 33 is slidably connected to the cavity 32. A push rod 34 is fixed on the sliding plug 33, and the sliding plug 33 is connected to the cavity 32 by a spring 35. A slot 315 is opened on the side of the clamping seat 31, and an air supply pipe 316 is arranged in the slot 315. One end of the air supply pipe 316 is connected to the cavity 32. An opening 314 is opened at the top of the clamping seat 31, and the opening 314 is connected to the cavity 32. The other end of the air supply pipe 316... One end is connected to the air source. The air source is existing technology and is not shown in the figure. It will not be described in detail here. Specifically, the air source supplies air to the cavity 32 through the air supply pipe 316. After the gas enters the cavity 32, it can push the slide plug 33 to move, so that the slide plug 33 is close to the opening 314. During this process, the slide plug 33 squeezes the spring 35 and drives the push rod 34 to move. The trigger part also includes an elastic bladder 41 and a movable block 42. The movable block 42 is placed above the clamping seat 31 and is set directly opposite the opening 314. One end of the elastic bladder 41 is connected to the clamping seat 31 and the other end is connected to the movable block 42.

[0047] See Figure 6As shown, the clamping part 551 includes two clamping members, both of which are arranged on the outer peripheral surface of the clamping base 31 and are positioned opposite each other. Each clamping member includes two side plates 51, both of which are fixed to the outer peripheral surface of the clamping base 31 and are positioned opposite each other. A slidable magnetic slide plate 52 is provided between the two side plates 51. The magnetic slide plate 52 is connected to the clamping base 31 by a tension spring 56. Each side plate 51 has a limit opening 53. Two limit blocks 54 are fixed on the magnetic slide plate 52, and the two limit blocks 54 slide in the two limit openings 53 respectively. The magnetic slide plate 52 moves... During the process, the two limiting ports 53 and the two limiting blocks 54 provide limits for the movement of the magnetic slide plate 52, ensuring the stability of the magnetic slide plate 52 during movement, and preventing the magnetic slide plate 52 from detaching from the two side plates 51. The magnetic slide plate 52 is attached with a clamping strip made of magnetic material, so that the clamping strip can be attached to the magnetic slide plate 52. The clamping strip is composed of a clamping part 551 and a driving part 552. The driving part 552 is fixed to the top of the clamping part 551, and the driving part 552 is provided with a slope. The clamping part 551 is used to hold the mouth of the plastic bottle, and the side of the clamping part 551 is attached with an anti-slip pad 553.

[0048] When gas enters cavity 32 and pushes the slide plug 33 to move, the push rod 34 on the slide plug 33 moves accordingly. During this process, the push rod 34 can pass through the opening 314 and lift the movable block 42, causing the movable block 42 to move upward. Figure 4 As shown, when the movable block 42 moves upward, it can press the inclined surfaces of the two driving parts 552. Under the action of the two inclined surfaces, the two driving parts 552 will move synchronously and move away from each other when they are pressed. This causes the two clamping parts 551 to move synchronously and move away from each other. When the two clamping parts 551 move away from each other, they can jointly support the bottle mouth of the plastic bottle, thereby fixing the plastic bottle and forming a shape as shown. Figure 10 As shown, in this state, the two clamping parts 551 enable the clamping seat 31 to move, flip and rotate the plastic bottle.

[0049] See Figure 9As shown, the machine vision-based plastic product defect detection device proposed in this invention also has the function of rejecting defective products. Specifically, the bottom surface of the clamping seat 31 is provided with a first vent hole 312, and the bottom surface of the clamping seat 31 is provided with a rotatable blocking plate 3121. The blocking plate 3121 is rotatably connected to the clamping seat 31 via a hinge. The blocking plate 3121 is positioned directly opposite the first vent hole 312. A torsion spring is provided on the hinge. Under the action of the torsion spring, the blocking plate 3121 tends to block the first vent hole 312. The outer peripheral surface of the clamping seat 31 is provided with a first vent hole 3122. The second exhaust port 313 has a movable blocking ring 3131 fitted on the outer peripheral surface of the clamping seat 31. The outer peripheral surface of the clamping seat 31 is also fixed with a limiting protrusion 3132, which provides a limit for the blocking ring 3131. When the blocking ring 3131 falls on the limiting protrusion 3132, the blocking ring 3131 is positioned directly opposite the second exhaust port 313. When gas is discharged through the first exhaust port 312, the device performs a rejection action for unqualified plastic bottles. When gas is discharged through the second exhaust port 313, the device performs a collection action for qualified plastic bottles.

[0050] See Figure 8 As shown, two limiting lips 311 are fixed on the outer peripheral surface of the clamping seat 31. The two limiting lips 311 together provide constraint for the plastic bottle. When the bottle mouth of the plastic bottle abuts against the two limiting lips 311, it indicates that the plastic bottle has been assembled in place. Two pulling parts are respectively arranged on the two limiting lips 311. The pulling parts include a second servo motor 61. The second servo motor 61 is mounted on the limiting lips 311. An eccentric wheel 62 is fixed on the output shaft of the second servo motor 61. A fixing rod 63 is fixed on the side of the eccentric wheel 62. The fixing rod 63 is located at the edge of the eccentric wheel 62. A rotating ring 64 is rotatably sleeved on the fixing rod 63. A pull rope 65 is connected to the rotating ring 64. For the two pull ropes 65, one pull rope 65 is connected to the blocking plate 3121, and the other pull rope 65 is connected to the blocking ring 3131.

[0051] In the industrial vision inspection process, when a plastic bottle fails to meet the requirements, the second servo motor 61, which drives the blocking plate 3121, runs and drives the corresponding eccentric wheel 62 to rotate. Figure 4 , Figure 5 and Figure 7As shown, in the initial state, the fixed rods 63 are all in the lower position. When the eccentric wheel 62 rotates, the fixed rods 63 move accordingly, driving the rotating ring 64 to move. This allows the rotating ring 64 to pull the blocking plate 3121 through the pull rope 65, causing the blocking plate 3121 to rotate. When the blocking plate 3121 rotates, it no longer blocks the first vent hole 312. At this time, the high-pressure gas in the cavity 32 can be discharged through the first vent hole 312, performing a venting action. During the venting process, the sliding plug 33 resets under the action of the spring 35, driving the push rod 34 to reset. When the push rod 34 resets, it no longer applies a pushing force to the movable block 42. This causes the movable block 42 to reset under the action of the elastic bladder 41. Similarly, when the movable block 42 resets, it no longer applies a squeezing action to the two drive parts 552. This causes the two clamping parts 551 to reset under the action of the two tension springs 56 respectively. During this process, the two clamping parts 551 no longer provide a clamping action to the plastic bottle. After the two clamping parts 551 have completed their reset, the jet action of the first exhaust hole 312 can blow the plastic bottle and blow it off the clamping seat 31, thereby achieving automatic rejection of unqualified plastic bottles. It should be noted that the rejection of unqualified plastic bottles is carried out when the plastic bottle is kept in a horizontal state.

[0052] When the plastic bottle is qualified, the blocking plate 3121 will not move, that is, the two clamping parts 551 will still hold the plastic bottle. When the plastic bottle rotates from the horizontal state to the vertical state, the pulling part used to drive the blocking ring 3131 will run, and the corresponding second servo motor 61 will run. Similarly, when the second servo motor 61 runs, the pulling rope 65 can apply a pulling force to the blocking ring 3131, causing the blocking ring 3131 to move. When the blocking ring 3131 moves, it will no longer block the second vent hole 313, and the gas in the cavity 32 can also slowly leak out through the second vent hole 313, so that the sliding plug 33, the push rod 34, the movable block 42 and the two clamping parts 551 will be reset. When the two clamping parts 551 are reset in place, the two clamping parts 551 will no longer fix the plastic bottle. At this time, the plastic bottle can fall naturally under the action of gravity, realizing the collection of qualified products.

[0053] It should be noted that the loading process of the plastic bottle onto the clamping seat 31 can be carried out manually or automatically by the machine. This part is existing technology and is not shown in the figure, so it will not be described in detail here.

[0054] Working principle:

[0055] When the machine vision-based plastic product defect detection device is working, the surrounding conveyor 13 on the frame 11 transports plastic bottles one by one, passing directly below the industrial vision inspection device 12. The conveyor is equipped with several clamping components consisting of a flipping structure and a clamping structure to hold the plastic bottles. Initially, the plastic bottles remain vertical after being clamped. Before passing through the inspection area, the first servo motor 22 of the flipping structure drives the swing frame 23 to rotate 90°, causing the plastic bottles to rotate to a horizontal position. During the process of entering the inspection area, the gear 26 meshes with the rack 112, causing the rotating frame 24 and the plastic bottles to slowly rotate. Simultaneously, the CDD in the industrial vision inspection device 12... The camera takes multiple photos to obtain samples from different angles, achieving comprehensive inspection. In the triggering part of the clamping structure, the air source supplies air to the cavity 32 of the clamping seat 31 through the air supply pipe 316, pushing the slide plug 33 to move and driving the push rod 34 to lift the movable block 42. The movable block 42 squeezes the inclined surfaces of the two driving parts 552, causing the two clamping parts 551 to move synchronously away from each other, supporting the position of the plastic bottle mouth to achieve fixation. For defective products, when the plastic bottle is unqualified, the second servo motor 61 used to drive the blocking plate 3121 drives the eccentric wheel 62 to rotate, and pulls the blocking plate 3121 through the pull rope 65 to no longer block the first exhaust hole 312. The high-pressure gas in the cavity 32 is discharged, the slide plug 33 resets, driving the push rod 34 to reset, and the movable block 42 in the elastic bladder 4 Under the action of 1, the two clamping parts 551 are reset and no longer clamp the plastic bottle under the action of the two tension springs 56. The first exhaust hole 312 blows the plastic bottle off the clamping seat 31. For qualified products, when the plastic bottle is qualified, the blocking plate 3121 does not move. After the plastic bottle rotates from the horizontal state to the vertical state, the pulling part used to drive the blocking ring 3131 runs. The second servo motor 61 pulls the blocking ring 3131 through the pull rope 65 and no longer blocks the second exhaust hole 313. The gas in the cavity 32 slowly leaks out through the second exhaust hole 313. The sliding plug 33, the top rod 34, the movable block 42 and the two clamping parts 551 are reset. The two clamping parts 551 no longer fix the plastic bottle. The plastic bottle falls naturally under the action of gravity.

[0056] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0057] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A machine vision-based defect detection device for plastic products, characterized in that: It includes a frame (11), on which an industrial vision inspection device (12) is installed, and on which a surround conveyor (13) is installed, and on which a vertical rod (111) is fixed, and a rack (112) is fixed at the top of the vertical rod (111). The surrounding conveying device (13) is provided with several clamping components for clamping plastic bottles. Each clamping component is composed of a flipping structure and a clamping structure. Each clamping structure is composed of a triggering part and a clamping part (551). The clamping part (551) includes two clamping members, which are arranged on the outer periphery of the clamping seat (31). The triggering part includes a clamping seat (31), the clamping seat (31) has a cavity (32) inside, a sliding plug (33) is slidably connected in the cavity (32), a top rod (34) is fixed on the sliding plug (33), and the sliding plug (33) and the cavity (32) are connected by a spring (35). The side of the clamping seat (31) has a slot (315), an air supply pipe (316) is arranged in the slot (315), one end of the air supply pipe (316) is connected to the cavity (32), and the top of the clamping seat (31) has an opening (314), and the opening (314) is connected to the cavity (32). The flipping structure includes a mounting frame (21), which is fixed on the annular conveyor belt of the wraparound conveyor (13). A first servo motor (22) is mounted on the mounting frame (21). A swing frame (23) is fixed on the output shaft of the first servo motor (22). A hole is provided on the swing frame (23). A rotating shaft (25) is rotatably mounted in the hole. A rotating frame (24) is fixed at one end of the rotating shaft (25), and a gear (26) is fixed at the other end. Both the swing frame (23) and the rotating frame (24) are U-shaped. The clamping seat (31) is fixed on the rotating frame (24). The triggering part also includes an elastic bladder (41) and a movable block (42). The movable block (42) is placed above the clamping seat (31) and is positioned directly opposite the opening (314). One end of the elastic bladder (41) is connected to the clamping seat (31), and the other end is connected to the movable block (42). Each of the clamping components includes two side plates (51), both of which are fixed to the outer periphery of the clamping base (31) and are arranged opposite each other. A slidable magnetic slide plate (52) is provided between the two side plates (51). The magnetic slide plate (52) is connected to the clamping base (31) by a tension spring (56). Limiting holes (53) are provided on both side plates (51). Two limiting blocks (54) are fixed on the magnetic slide plate (52). The two limiting blocks (54) slide in the two limiting holes (53) respectively. A clamping strip is adsorbed on the magnetic slide plate (52). The clamping strip is composed of a clamping part (551) and a driving part (552). The driving part (552) is fixed to the top of the clamping part (551) and has an inclined surface. The clamping part (551) is used to hold the mouth of the plastic bottle.

2. The machine vision-based defect detection device for plastic products according to claim 1, characterized in that: The bottom surface of the clamping seat (31) is provided with a first vent hole (312). The bottom surface of the clamping seat (31) is provided with a rotatable blocking plate (3121), and the blocking plate (3121) is rotatably connected to the clamping seat (31) through a hinge. The blocking plate (3121) is positioned opposite the first vent hole (312). A torsion spring is provided on the hinge. The outer peripheral surface of the clamping seat (31) is provided with a second vent hole (313). The outer peripheral surface of the clamping seat (31) is fitted with a movable blocking ring (3131). The outer peripheral surface of the clamping seat (31) is also fixed with a limiting protrusion (3132). The limiting protrusion (3132) provides a limit for the blocking ring (3131). When the blocking ring (3131) falls on the limiting protrusion (3132), the blocking ring (3131) is positioned opposite the second vent hole (313). The outer peripheral surface of the clamping seat (31) is fixed with two limiting lips (311), which together provide constraint for the plastic bottle. Each of the two limiting lips (311) is provided with a pulling part.

3. The machine vision-based defect detection device for plastic products according to claim 2, characterized in that: When gas is discharged through the first vent (312), the device performs a rejection action for unqualified plastic bottles; when gas is discharged through the second vent (313), the device performs a collection action for qualified plastic bottles.

4. The machine vision-based defect detection device for plastic products according to claim 3, characterized in that: The pulling part includes a second servo motor (61), which is mounted on a limiting lip (311). An eccentric wheel (62) is fixed to the output shaft of the second servo motor (61). A fixing rod (63) is fixed to the side of the eccentric wheel (62), and the fixing rod (63) is located at the edge of the eccentric wheel (62). A rotating ring (64) is rotatably sleeved on the fixing rod (63). A pull rope (65) is connected to the rotating ring (64). For the two pull ropes (65), one of the pull ropes (65) is connected to the blocking plate (3121), and the other pull rope (65) is connected to the blocking ring (3131).

5. The machine vision-based defect detection device for plastic products according to claim 4, characterized in that: The side of the clamping part (551) is bonded with an anti-slip pad (553).

6. The machine vision-based defect detection device for plastic products according to claim 1, characterized in that: The top rod (34) is positioned opposite the opening (314).

7. The machine vision-based defect detection device for plastic products according to claim 1, characterized in that: Both the magnetic sliding plate (52) and the clamping bar are made of magnetic material.

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