A lithium battery edge defect detection device

Abstract

The utility model relates to a kind of lithium battery edge defect detection devices, involve industrial vision detection technical field;Using 8° angle point light source bilateral light supplement lighting mode, collate two-camera segmented type shooting structure, the uniform light path of point light source is attached lithium battery edge camber characteristics, two-camera is set with 45°±10° rotation angle, 225mm interval, the complete imaging of different size lithium battery edge is realized.The utility model effectively improves the imaging uniformity and stability, eliminates edge high light interference, without manual separate reinspection, save labor cost while improving product yield and safety, adapt high-speed detection machine to improve production efficiency, suitable for various lithium battery edge defect industrial vision detection scene.

Description

Technical Field

[0001] This utility model relates to the field of industrial visual inspection technology, and in particular to a lithium battery edge defect detection device. Background Technology

[0002] With the rapid development of the lithium battery industry, the requirements for its safety and consistency are increasing. Visual inspection technology, due to its advantages of non-contact operation, high efficiency, and high precision, is widely used for detecting appearance defects in lithium batteries. The edges of lithium batteries are critical parts of their structure; defects in these areas (such as scratches, dents, and burrs) are often safety defects that directly affect the battery's safety performance.

[0003] Currently, visual inspection technology for the flat surface of lithium batteries is relatively mature, typically employing a camera paired with an open-aperture surface light or a ring light source, utilizing the principle of light refraction for imaging. However, the unique edge structure and significant dimensional variations of lithium batteries present significant limitations to existing technologies.

[0004] 1. To be compatible with lithium batteries of different sizes, it is usually necessary to lengthen the emitting surface of the light source. However, for light sources with a central hole (such as open-aperture light), increasing the emitting surface often results in an increase in the size of the central hole, leading to insufficient brightness in the central area of ​​the captured image and poor uniformity.

[0005] 2. To improve the brightness of the central area of ​​the image, supplementary light sources are sometimes added to both sides of the product. However, if the angle or position of the supplementary light source is inappropriate, or if it is too close to the product surface, it is very easy to form a highly reflective band in the edge area, which can cover up the real defects and seriously affect the accuracy of the detection.

[0006] These issues prevent existing equipment from effectively imaging the edges of lithium batteries, requiring manual re-inspection of finished products. This results in drawbacks such as high labor costs, low inspection efficiency, and strong subjectivity in defect judgment, affecting product yield and safety. Utility Model Content

[0007] The technical problem to be solved by this utility model is to provide a lithium battery edge defect detection device, which effectively eliminates the interference of high reflectivity at the edges and achieves complete and uniform imaging of the edges, thereby improving the accuracy and efficiency of defect detection.

[0008] The technical solution adopted by this utility model to solve its technical problem is: a lithium battery edge defect detection device, including a symmetrically arranged dual camera assembly and a dual-side point light source assembly, wherein the dual camera assembly and the dual-side point light source assembly cooperate to achieve complete imaging of the lithium battery edge.

[0009] The dual-camera assembly includes two area array cameras, which are symmetrically distributed along the central axis of the lithium battery edge. The shooting areas of the two area array cameras partially overlap to form a segmented full-coverage shooting structure.

[0010] The dual-sided point light source assembly includes two industrial point light sources with identical parameters. The two point light sources are respectively set on both sides of the lithium battery edge and are symmetrical along the central axis of the lithium battery edge. The illumination direction of each point light source forms an 8° angle with the tangent direction of the lithium battery edge. The luminous center of the point light source is 80mm away from the horizontal distance between the lithium battery edge and the light source. The light path scattering area of ​​the point light source conforms to the arc contour of the lithium battery edge.

[0011] Furthermore, the rotation angle of each area array camera in this invention is 45°±10°, and the vertical distance between the camera lens and the edge surface of the lithium battery is fixed at 225mm.

[0012] Furthermore, the dual-camera assembly and the dual-side point light source assembly described in this utility model are both fixedly installed on the bracket of a testing machine.

[0013] Furthermore, the width of the overlapping area captured by the two area array cameras described in this utility model is 10%-15% of the length of the edge of the lithium battery.

[0014] Furthermore, the signal output terminals of the two area array cameras described in this utility model are synchronously connected to the back-end image processing system. The image processing system receives the segmented images from the two cameras and stitches and fuses them to form a complete panoramic image of the lithium battery edge, which is used for defect identification and analysis.

[0015] The beneficial effect of this utility model is that it solves the defects existing in the background technology.

[0016] 1. By using an 8° angled point light source for dual-sided supplemental lighting, combined with segmented shooting, the problem of dark center imaging and strong edge reflection of lithium batteries of different sizes is solved, resulting in high consistency of imaging effect.

[0017] 2. The combination of dual-camera segmented shooting and point light source supplementary lighting is compatible with lithium batteries of various sizes, without the need to adjust the light source structure, making it more adaptable.

[0018] 3. The device has stable imaging and strong anti-interference ability, which can clearly present the characteristics of edge defects, realize quantitative detection, replace manual re-inspection, save labor costs, reduce the defect misjudgment rate, and improve product yield and safety.

[0019] 4. The device has a simple structure and can be integrated into a high-speed testing machine, which greatly improves the testing efficiency in the lithium battery production process and meets the needs of industrial mass production. Attached Figure Description

[0020] Figure 1This is a front view of the optical path of the imaging system of this utility model;

[0021] Figure 2 This is a side view of the optical path of the imaging system of this utility model;

[0022] Figure 3 Comparison of light source imaging methods (a: point light source imaging, b: ordinary light source supplementary lighting imaging, c: ordinary light source imaging);

[0023] In the image: 1. Area scan camera, 2. Point light source, 3. Lithium battery product. Detailed Implementation

[0024] The present invention will now be described in further detail with reference to the accompanying drawings and preferred embodiments. These drawings are simplified schematic diagrams, illustrating only the basic structure of the present invention, and therefore only show the components relevant to the present invention.

[0025] like Figures 1-2 The lithium battery edge defect detection device shown includes a camera assembly and a light source assembly. In this embodiment, an area array camera 1 is selected, with a resolution that meets the requirements for edge defect detection. A high-stability point light source 2 is selected as the point light source to ensure that the illumination angle is accurately controlled at 8°. During installation, the two area array cameras are symmetrically fixed, and the rotation angle is adjusted to 45° so that the vertical distance between the center of the camera lens and the edge of the lithium battery product 3 is maintained at 225mm. The two point light sources are fixed on both sides of the product edge, and the lateral spacing is adjusted to 80mm to ensure that the illumination direction forms an 8° angle with the tangent of the edge. The uniform light path of the point light source is used to illuminate the curved surface of the edge, thereby enabling the camera to image the image.

[0026] During testing, the lithium battery moves along the testing path, and the dual point light sources simultaneously illuminate the edge area at an 8° angle. The scattered light path fits the curved surface of the edge, achieving uniform supplementary lighting. The dual cameras take segmented pictures of the edges of lithium batteries of different sizes according to preset angles and spacings. The light path characteristics of the point light source are used to eliminate the problems of high reflectivity at the edges and dark imaging in the center, and finally obtain complete and clear edge images, providing a stable imaging basis for subsequent defect identification.

[0027] During the inspection, the lithium battery passes through the inspection area at a constant speed, while dual cameras simultaneously capture images in segments. A point light source provides continuous dual-sided illumination, and the light path conforms to the curved surface of the edge to create a uniformly illuminated area, avoiding high reflectivity and a dark central area. The captured images are transmitted to the back-end processing system for automatic identification and judgment of edge defects.

[0028] By supplementing light to both sides of the product's edges, the overall imaging performance is uniform, with consistent performance in both the central and lateral areas. Compared to ordinary light source paths and ordinary supplementary light source paths, this eliminates the high reflectivity of corners caused by supplementary lighting on the edges. It also solves the problem of darker images in the central area when using ring light or center aperture surface light, which is currently the mainstream method. This significantly improves the imaging effect, enhances the appearance of surface defects on edges, and makes edges easier to inspect using industrial vision. (Light source imaging method comparison: [example not provided]) Figure 3 As shown.

[0029] The above description is only a specific embodiment of the present utility model. Various examples and illustrations do not constitute a limitation on the substantive content of the present utility model. Those skilled in the art can make modifications or variations to the above-described specific embodiments after reading the description without departing from the essence and scope of the utility model.

Claims

1. A lithium battery edge defect detection device, characterized in that: It includes a symmetrically arranged dual-camera assembly and a dual-side point light source assembly, wherein the dual-camera assembly and the dual-side point light source assembly work together to achieve complete imaging of the edges of the lithium battery; The dual-camera assembly includes two area array cameras, which are symmetrically distributed along the central axis of the lithium battery edge. The shooting areas of the two area array cameras partially overlap to form a segmented full-coverage shooting structure. The dual-sided point light source assembly includes two industrial point light sources with identical parameters. The two point light sources are respectively set on both sides of the lithium battery edge and are symmetrical along the central axis of the lithium battery edge. The illumination direction of each point light source forms an 8° angle with the tangent direction of the lithium battery edge. The luminous center of the point light source is 80mm away from the horizontal distance between the lithium battery edge and the light source. The light path scattering area of ​​the point light source conforms to the arc contour of the lithium battery edge.

2. The lithium battery edge defect detection device as described in claim 1, characterized in that: Each area array camera rotates at an angle of 45°±10°, and the vertical distance between the camera lens and the edge surface of the lithium battery is fixed at 225mm.

3. The lithium battery edge defect detection device as described in claim 1, characterized in that: Both the dual-camera assembly and the dual-side point light source assembly are fixedly mounted on a bracket of a testing machine.

4. The lithium battery edge defect detection device as described in claim 1, characterized in that: The width of the overlapping area captured by the two area scan cameras is 10%-15% of the length of the lithium battery edge.

5. The lithium battery edge defect detection device as described in claim 1, characterized in that: The signal output terminals of the two area array cameras are synchronously connected to the back-end image processing system. The image processing system receives the segmented images from the two cameras and stitches and fuses them to form a complete panoramic image of the lithium battery edges, which is used for defect identification and analysis.

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