A zipper defect detection device based on vision

Abstract

The present invention discloses a zipper defect detection device based on vision, which includes a conveying device, a cutting device, a visual system and a control system connecting the first three; the conveying device includes a carrier and a transport unit; the cutting device is arranged between the carrier and the transport unit; the visual system includes a first camera and a second camera for acquiring images of the front and back sides of the tape, a third camera for acquiring images of the chain tooth part, and a fourth camera and a fifth camera for acquiring images of the two ends of the finished zipper; the first camera and the second camera are respectively arranged on the upper side and the lower side of the carrier; the third camera is arranged between the carrier and the transport unit; the fourth camera and the fifth camera are both arranged above the transport unit. The present invention is provided with cameras for different parts of the zipper, and a lighting light source that meets the conditions is respectively provided according to the part where each camera acquires the image, and the control system can respectively identify the defects of each part according to the images collected by each camera.

Description

Technical Field

[0001] The present invention relates to the technical field of product quality detection, and in particular to a zipper defect detection device based on vision. Background Art

[0002] Zippers are widely used in daily necessities such as clothing, bags, tents, etc. Zippers need to be quality inspected before leaving the factory to determine whether the zippers are released properly.

[0003] In the prior art, patent CN205317233U discloses a zipper visual inspection system, which includes multiple groups of detection devices 112 including light sources and cameras arranged along a guide rail 113, and the spacing between the detection devices 112 is adjustable. The system can simultaneously inspect the slider, top stop, bottom stop or square latch in the zipper. However, in the system, the structures of all the detection devices 112 are the same. Since the zipper is composed of many parts (including cloth tape, chain teeth, top and bottom stops, buckles, squares, etc.), the materials of each part are different, and the defect types are also different. Therefore, different lighting conditions are required to detect defects in each part. Therefore, the system can only detect some obvious defects, and cannot detect defects such as injection defects and scratches on the chain teeth.

[0004] Patent CN112189951A provides a system that uses two upper and lower CCD cameras to collect images of products and judge whether the zipper has surface defects. In the above-mentioned prior art, it is difficult for the image recognition system to fully judge the defects of various parts of the zipper by only relying on the images collected by two CCD cameras. Patents CN106706656A, CN209559773U and other patents also adopt similar camera layouts and have the same defects.

[0005] In addition, all the above-mentioned prior arts can only detect the zipper material, but cannot detect the two ends of the finished zipper. Summary of the invention

[0006] Purpose of the invention: In order to overcome the deficiencies in the prior art, the present invention provides a vision-based zipper defect detection device with a full range of detection types and a reasonable camera layout.

[0007] Technical solution: To achieve the above-mentioned purpose, the vision-based zipper defect detection device of the present invention includes a conveying device, a cutting device, a vision system and a control system connecting the first three;

[0008] The conveying device includes a carrier platform for supporting and guiding the zipper material in a straight state and a transport unit for transporting the cut zipper product; the cutting device is arranged between the carrier platform and the transport unit;

[0009] The visual system includes a plurality of cameras equipped with light sources, which are: a first camera and a second camera for acquiring images of the front and back sides of the tape, a third camera for acquiring images of the sprockets, upper and lower stops, and buckle parts, and a fourth camera and a fifth camera for acquiring images of the two ends of the finished zipper, respectively;

[0010] The first camera and the second camera are respectively placed on the upper side and the lower side of the carrier; the third camera is placed between the carrier and the transport unit; the fourth camera and the fifth camera are both placed above the transport unit;

[0011] There is a gap between the carrier platform and the transport unit; the third camera is arranged directly above or below the gap position, and a third light source and a fourth light source for use with the third camera are respectively arranged directly above and below the gap position; when the zipper defect detection device is in operation, the zipper material that has not been cut off passes between the third light source and the fourth light source.

[0012] Furthermore, a vertically penetrating viewing window is provided on the carrier platform, the upper end of the viewing window is covered with optical glass, and the second camera is placed directly below the viewing window with its lens facing upward.

[0013] Furthermore, the first camera and the second camera are respectively equipped with a first light source and a second light source.

[0014] Furthermore, the distance between the fourth camera and the fifth camera is adjustable.

[0015] Furthermore, the fourth camera is fixed on a machine base, a first linear module is installed on the machine base, and the fifth camera is installed on a motion unit of the first linear module.

[0016] Furthermore, the movement direction of the zipper material on the carrying platform is perpendicular to the transport direction of the transport unit.

[0017] Furthermore, the conveying device also includes a pulling device, and the pulling device includes a clamping assembly and a second linear module for driving the clamping assembly to move.

[0018] Beneficial effects: The vision-based zipper defect detection device of the present invention is respectively provided with cameras for different parts of the zipper, and is equipped with qualified lighting light sources according to the parts where each camera obtains images. The control system can respectively identify the defects of each part according to the images collected by each camera. In addition, the detection process is set on the front and back sides of the zipper cutting device, and the camera for detection is divided into two parts. The two cameras are respectively arranged before and after the zipper is finally cut off. The zipper tape and sprocket teeth are inspected before the zipper is cut off, and the two ends of the zipper are inspected after the zipper is cut off, so that the detection of all parts of the zipper can be realized. The camera layout is reasonable and compact, and the detection efficiency is high. The third light source and the fourth light source are oppositely irradiated to illuminate the sprocket teeth and other parts of the zipper, so as to effectively find defects such as poor injection molding and scratches. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a structural diagram of a zipper defect detection device based on vision;

[0020] Figure 2 This is a partial enlarged view of the first perspective of the vision-based zipper defect detection device;

[0021] Figure 3 A partial enlarged view of the second viewing angle of the vision-based zipper defect detection device;

[0022] Figure 4 This is a structural diagram of the carrier platform.

[0023] In the figure: 1-conveying device; 11-carrying platform; 111-window; 112-trough; 12-transport unit; 13-pulling device; 131-clamping assembly; 132-second linear module; 2-cutting device; 3-visual system; 31-first camera; 32-second camera; 33-third camera; 34-fourth camera; 35-fifth camera; 36-first light source; 37-second light source; 38-third light source; 39-fourth light source; 310-fifth light source; 320-sixth light source; 4-base; 5-first linear module. DETAILED DESCRIPTION

[0024] The present invention will be further described below in conjunction with the accompanying drawings.

[0025] like Figure 1The visual-based zipper defect detection device shown includes a machine base 4, on which a conveying device 1, a cutting device 2, a visual system 3 and a connection between the first three are installed; the conveying device 1 includes a carrier 11 that provides support and guidance for the zipper material in a straight state and a transport unit 12 for transporting the cut zipper product; the cutting device 2 is arranged between the carrier 11 and the transport unit 12. The conveying device 1 also includes a pulling device 13, which is used to move the zipper material in a straight state along the carrier 11, and the above-mentioned transport unit 12 can be actively operated. Specifically, the pulling device 13 includes a clamping assembly 131 and a second linear module 132 for driving the clamping assembly 131 to move. During operation, the clamping assembly 131 clamps the end of the zipper material, and the second linear module 132 drives the clamping assembly 131 to move, so that the zipper material moves along the carrier 11.

[0026] The zipper defect detection device also includes a control system. The above-mentioned conveying device 1, cutting device 2 and visual system 3 are all connected to the control system. The control system can control the three to move in coordination, and can also determine whether there are defects in various parts of the zipper based on the images collected by the cameras of the visual system 3.

[0027] The above-mentioned zipper material is continuous and uninterrupted, and includes many continuously connected zipper units. After the zipper material is cut at equal distances by the cutting device 2, the zipper units are cut off one by one to form a finished zipper product. The finished zipper product (i.e., the zipper unit on the zipper material) includes two chain belt parts, a block and a buckle. The chain belt part is composed of a cloth belt and chain teeth arranged in a linear array on the cloth belt. In the initial form, the block fixes one end of the two chain belts together, and the buckle in each zipper unit in the zipper material is placed in the middle of the two chain belts, so that one part of the two chain belts is in a locked state, and the other part is in a separated state.

[0028] like Figure 3 and Figure 4 As shown, the visual system 3 includes a first camera 31 and a second camera 32 for acquiring images of the front and back sides of the tape, a third camera 33 for acquiring images of the sprockets, upper and lower stops, and buckle parts, and a fourth camera 34 and a fifth camera 35 for acquiring images of the two ends of the finished zipper respectively; the first camera 31 and the second camera 32 are respectively placed on the upper and lower sides of the carrier 11; the third camera 33 is placed between the carrier 11 and the transport unit 12; the fourth camera 34 and the fifth camera 35 are both placed above the transport unit 12.

[0029] In the above-mentioned visual system 3, all cameras are divided into two parts. The first camera 31, the second camera 32 and the third camera 33 detect the tape and the sprocket part of the zipper unit before the zipper unit is cut off by the cutting device 2; the fourth camera 34 and the fifth camera 35 detect the two ends of the finished zipper after the zipper unit is cut off by the cutting device 2 to become the finished zipper. The zipper material is pulled and moved at one end. Before the zipper unit to be cut off is cut off, the zipper unit is pulled and moved together with the entire zipper material. At this time, it is more conducive to the detection of the tape and the sprocket part, and the detection is more comprehensive, and the tape part and the sprocket part at both ends of the zipper unit will not be missed.

[0030] In the above-mentioned visual system 3, all cameras are arranged around the cutting device 2, and the layout is reasonable and compact, so that the zipper can be visually inspected in all directions.

[0031] The following is a detailed description of how to install each camera.

[0032] The carrier 11 is a long strip structure, and has a groove 112 for the strip-shaped zipper material to move in. The bottom of the groove 112 supports the zipper material unfolded into a straight strip, and the two sides of the groove 112 guide the zipper material. The first camera 31 is installed just above the front end of the groove 112. Figure 4 As shown, the carrier 11 is provided with a window 111 which is through from top to bottom. The upper end of the window 111 is covered with an optical glass 14. The upper end of the optical glass 14 is flush with the bottom end of the tank 112. The second camera 32 is placed directly below the window 111, and its lens is placed upward. The first camera 31 and the second camera 32 are respectively provided with a first light source 36 and a second light source 37. Both the first light source 36 and the second light source 37 are annular light sources. Different from patents CN106706656A and CN112189951A, in the present invention, the first camera 31 and the second camera 32 are staggered in the extension direction of the tank 112 to prevent the light sources of the two from interfering with each other and affecting the imaging of the tape portion. In this way, the first camera 31 and the second camera 32 can respectively obtain images of the upper and lower sides of the tape, and detect both sides of the tape at the same time. The visual system in the prior art can often only detect one side or requires the help of a flip tool to achieve double-sided detection. Compared with the above, the scheme of the present invention is more convenient to obtain double-sided images.

[0033] There is a gap between the carrier platform 11 and the transport unit 12. When the zipper material is pulled, a part of the zipper material crosses the gap and is suspended. The third camera 33 is arranged directly above or below the gap. In this embodiment, the third camera 33 is arranged directly below the gap with the lens facing upward. A third light source 38 and a fourth light source 39 used in conjunction with the third camera 33 are respectively arranged directly above and below the gap. Both the third light source 38 and the fourth light source 39 are flat-plate light sources, and the light source on the same side as the third camera 33 has a through hole to make way for the camera's field of view. When the zipper defect detection device is in operation, a partial part of the zipper material that has not been cut off (that is, the suspended part) passes between the third light source 38 and the fourth light source 39. Through the upper and lower irradiation of the third light source 38 and the fourth light source 39, the chain teeth and other parts can be fully illuminated. In this way, it is easier to find defects such as scratches, missing parts, and poor injection molding on the chain teeth based on the image captured by the third camera 33.

[0034] Preferably, in order to facilitate the detection of both ends of zippers of different lengths, the distance between the fourth camera 34 and the fifth camera 35 can be adjusted. Specifically, the fourth camera 34 is fixed on the base 4, the base 4 is equipped with a first linear module 5, and the fifth camera 35 is installed on the motion unit of the first linear module 5. The control system can automatically control the operation of the first linear module 5 according to the model of the finished zipper to adjust the distance between the fourth camera 34 and the fifth camera 35 to adapt to different zippers.

[0035] The fourth camera 34 and the fifth camera 35 are respectively equipped with a fifth light source 310 and a sixth light source 320 for auxiliary lighting.

[0036] Preferably, the moving direction of the zipper material on the carrier 11 is perpendicular to the transport direction of the transport unit 12, and the connecting line between the fourth camera 34 and the fifth camera 35 is also perpendicular to the transport direction of the transport unit 12. In this way, after the zipper unit is cut into a finished zipper and falls onto the transport unit 12, the length extension direction of the finished zipper is perpendicular to the transport direction of the transport unit 12, and the fourth camera 34 and the fifth camera 35 can more easily capture images of both ends of the finished zipper. Preferably, the transport unit 12 is operated in a step-by-step manner, that is, it transports a fixed distance each time, so that both ends of the finished zipper can be temporarily left under the fourth camera 34 and the fifth camera 35 for a short period of time for the fourth camera 34 and the fifth camera 35 to take pictures.

[0037] Based on the above zipper defect detection device, the zipper detection method (which is implemented by the control system) is as follows (the following step numbers are not used to constrain the execution order of each step):

[0038] Step 1), controlling the clamping assembly 131 to clamp the end of the zipper material;

[0039] Step 2), controlling the second linear module 132 to operate so that the clamping assembly 131 is translated by a set distance; during the translation of the clamping assembly 131, the first camera 31, the second camera 32 and the third camera 33 respectively obtain images of the zipper material passing through their fields of view, and perform image recognition on the images to determine whether there are defects, and associate the judgment result with the zipper unit corresponding to the image (corresponding to the subsequent zipper finished product);

[0040] Step 3), controlling the cutting device 2 to operate so as to cut off the zipper unit at the end to form a finished zipper;

[0041] Step 4), controlling the transport unit 12 to operate so that each zipper product on it passes under the fourth camera 34 and the fifth camera 35 in sequence, and controlling the fourth camera 34 and the fifth camera 35 to obtain images of both ends of each zipper product, and performing image recognition on the image to determine whether there are defects, and associating the determination result with the zipper product corresponding to the image;

[0042] Step 5), determine whether there is a defective result among all the judgment results corresponding to the same zipper finished product. If so, mark the zipper finished product as a defective product, otherwise mark the zipper finished product as a qualified product.

[0043] The vision-based zipper defect detection device of the present invention is provided with cameras for different parts of the zipper, and is equipped with qualified lighting sources according to the parts where each camera obtains images. The control system can distinguish the defects of each part according to the images collected by each camera. In addition, the detection process is set on the front and back sides of the zipper cutting device, and the camera for detection is divided into two parts. The two cameras are respectively arranged before and after the zipper is finally cut. The zipper tape and chain teeth are inspected before the zipper is cut, and the two ends of the zipper are inspected after the zipper is cut, so that the detection of all parts of the zipper can be realized. The camera layout is reasonable and compact, and the detection efficiency is high.

[0044] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A zipper defect detection device based on vision, characterized in that: It includes a conveying device (1), a cutting device (2), a visual system (3), and a control system connecting the first three; The conveying device (1) comprises a carrier platform (11) for supporting and guiding the zipper material in a straight state, and a transport unit (12) for transporting the cut zipper product; the cutting device (2) is arranged between the carrier platform (11) and the transport unit (12); The visual system (3) comprises a plurality of cameras equipped with light sources, namely: a first camera (31) and a second camera (32) for acquiring images of the front and back sides of the tape, a third camera (33) for acquiring images of the sprockets, upper and lower stops, and buckle parts, and a fourth camera (34) and a fifth camera (35) for acquiring images of the two ends of the finished zipper, respectively; The first camera (31) and the second camera (32) are respectively placed on the upper side and the lower side of the carrier platform (11); the third camera (33) is placed between the carrier platform (11) and the transport unit (12); the fourth camera (34) and the fifth camera (35) are both placed above the transport unit (12); There is a gap between the carrier platform (11) and the transport unit (12); the third camera (33) is arranged directly above or directly below the gap, and a third light source (38) and a fourth light source (39) used in conjunction with the third camera (33) are respectively arranged directly above and directly below the gap; The carrier platform (11) is provided with a groove (112) in which the strip-shaped zipper material moves; the first camera (31) and the second camera (32) are staggered in the extension direction of the groove (112); The zipper detection method includes the following steps: Step 1), controlling the clamping assembly (131) to clamp the end of the zipper material; Step 2), controlling the second linear module (132) to operate so that the clamping assembly (131) is translated by a set distance; during the translation of the clamping assembly (131), the first camera (31), the second camera (32) and the third camera (33) respectively obtain images of the zipper material passing through their fields of view, and perform image recognition on the images to determine whether there are defects, and associate the determination result with the zipper unit corresponding to the image; Step 3), controlling the cutting device (2) to operate so as to cut off the zipper unit at the end to form a finished zipper product; Step 4), controlling the transport unit (12) to operate so that each zipper product on the transport unit (12) passes under the fourth camera (34) and the fifth camera (35) in sequence, and controlling the fourth camera (34) and the fifth camera (35) to obtain images of both ends of each zipper product, and performing image recognition on the images to determine whether there are defects, and associating the determination result with the zipper product corresponding to the image; Step 5) determines whether there is a defective result among all the judgment results corresponding to the same zipper finished product. If yes, the zipper finished product is marked as a defective product, otherwise, the zipper finished product is marked as a qualified product.

2. The zipper defect detection device based on vision according to claim 1 is characterized in that: The carrier platform (11) is provided with a vertically penetrating window (111), the upper end of the window (111) is covered with optical glass (14), and the second camera (32) is placed directly below the window (111) with its lens facing upwards.

3. The visual-based zipper defect detection device according to claim 2, characterized in that: The first camera (31) and the second camera (32) are respectively equipped with a first light source (36) and a second light source (37).

4. The vision-based zipper defect detection device according to claim 1, characterized in that: The distance between the fourth camera (34) and the fifth camera (35) is adjustable.

5. The vision-based zipper defect detection device according to claim 4, characterized in that: The fourth camera (34) is fixed on a machine base (4), a first linear module (5) is mounted on the machine base (4), and the fifth camera (35) is mounted on a motion unit of the first linear module (5).

6. The vision-based zipper defect detection device according to claim 1, characterized in that: The movement direction of the zipper material on the carrier platform (11) is perpendicular to the transport direction of the transport unit (12).

7. The vision-based zipper defect detection device according to claim 1, characterized in that: The conveying device (1) further comprises a pulling device (13), wherein the pulling device (13) comprises a clamping assembly (131) and a second linear module (132) for driving the clamping assembly (131) to move.

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