Device and method for measuring cylindricity of cylindrical battery cell

Abstract

A device and method for measuring the cylindricity of a cylindrical battery cell. The device (100) for measuring the cylindricity of a cylindrical battery cell (200) comprises a support (101) and a loading platform (102) mounted on the support (101), the loading platform (102) being used for loading a cylindrical battery cell (200); and a plurality of image capture devices (103) each mounted on the support (101), the plurality of image capture devices (103) being used for obtaining image information of the cylindrical battery cell (200), so as to construct a cylindrical surface based on the image information and obtain the cylindricity of the cylindrical battery cell (200) based on the constructed cylindrical surface.

Description

Cylindricity detection device and detection method for cylindrical battery cells

[0001] Related applications

[0002] This application claims priority to Chinese patent application No. 202311013631.2, filed on August 14, 2023, entitled “Device and method for detecting cylindrical battery cells”, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present application relates to the technical field of lithium battery size detection, and in particular to a cylindricity detection device and method for cylindrical battery cells. Background Art

[0004] In the lithium battery industry, battery dimensional control is becoming increasingly stringent. Cylindricity monitoring of cylindrical cells is relatively difficult due to the complexity of imaging the cylindrical surface. Currently, cylindrical surface dimension inspection for cylindrical cells primarily focuses on controlling the diameter of the cylindrical cell, with no clear cylindricity inspection solution available. However, cylindricity, as a key monitoring dimension for cylindrical cells, directly reflects the external appearance of the cylindrical surface, making its control essential.

[0005] In view of this, it is necessary to provide a new cylindrical battery cell cylindricity detection device and detection method to solve or at least alleviate the above technical defects.

[0006] Summary of the Invention

[0007] In view of the above problems, the present application provides a cylindrical battery cell cylindricity detection device and detection method, aiming to solve the technical problem in the related art that it is difficult to detect the cylindricity of cylindrical battery cells.

[0008] In a first aspect, the present application provides a cylindrical battery cell cylindricity detection device, comprising:

[0009] Bracket;

[0010] A loading platform, the loading platform is mounted on the bracket and is used to load cylindrical battery cells;

[0011] Multiple image acquisition devices are installed on the bracket; the multiple image acquisition devices are used to obtain image information of the cylindrical battery cell, to construct a cylindrical surface according to the image information, and to obtain the cylindricity of the cylindrical battery cell according to the constructed cylindrical surface.

[0012] By providing a stage for placing a cylindrical battery cell and employing multiple image acquisition devices to scan the cylindrical battery cell's side from various directions, image information from all directions of the side can be simultaneously acquired. A cylindrical surface can be constructed based on the image information, and the cylindricity of the cylindrical battery cell can be determined based on the constructed cylindrical surface. This embodiment has the advantage of being able to directly detect the cylindricity of the cylindrical battery cell and providing accurate measurement results.

[0013] In some embodiments, the plurality of image acquisition devices are evenly distributed along the circumference of the cylindrical battery core.

[0014] By evenly distributing multiple image acquisition devices along the circumference of the cylindrical battery cell, the entire circumference of the cylindrical battery cell can be covered, and the number of image acquisition devices can be reduced, thereby reducing production costs.

[0015] In some embodiments, the plurality of image acquisition devices are spaced apart and distributed along the central axis of the cylindrical battery core.

[0016] By distributing image acquisition devices at intervals along the central axis of the cylindrical cell, mutual interference between the laser beams emitted by the laser scanners of the image acquisition devices can be reduced, ensuring accurate imaging and obtaining clear images, facilitating subsequent image processing. Furthermore, with a minimal number of image acquisition devices, the entire cylindrical surface of the cylindrical cell can be fully covered. This ensures detection accuracy while reducing the number of image acquisition devices and lowering the manufacturing cost and computational complexity of the cylindrical cell cylindricity detection device.

[0017] In some embodiments, multiple image acquisition devices take photos of the cylindrical battery cell to obtain image information, so as to obtain a peripheral 3D image of the cylindrical battery cell based on the image information, and take a first preset number of detection surfaces at preset positions on the peripheral 3D image, and take a second preset number of detection points on each of the detection surfaces, and obtain the cylindricity of the cylindrical battery cell based on the difference in radius of the cylindrical surface constructed by the detection points on each of the detection surfaces.

[0018] The cylindrical battery cell is photographed by multiple image acquisition devices to obtain image information, a peripheral 3D image of the cylindrical battery cell is obtained based on the image information, and the cylindricity of the cylindrical battery cell is obtained through a preset degree of the image acquisition device. The cylindricity of the cylindrical battery cell can be directly obtained with high detection accuracy.

[0019] In some embodiments, the image acquisition device includes three 3D line scan cameras respectively installed on the bracket, the three 3D line scan cameras are evenly distributed along the outer circumference of the cylindrical battery core, and the three 3D line scan cameras are spaced apart along the central axis direction of the cylindrical battery core.

[0020] By distributing three 3D line scan cameras at intervals along the outer circumference of a cylindrical cell, the entire side of the cylindrical cell can be imaged while improving detection accuracy. This reduces the number of image acquisition devices, lowering the manufacturing cost and computational complexity of the cylindrical cell cylindricity detection device. By distributing the image acquisition devices at intervals along the central axis of the cylindrical cell, mutual interference between the laser beams emitted by the image acquisition devices' laser scanners is reduced, ensuring accurate imaging and capturing images of the entire height of the cylindrical cell's side, facilitating subsequent image processing.

[0021] In some embodiments, the bracket includes a mounting column and three upright columns, the stage is mounted on the mounting column, the three upright columns are arranged around the periphery of the stage, and the three 3D line scan cameras are mounted on the three upright columns in a one-to-one correspondence.

[0022] By setting up mounting columns, an installation position is provided for the stage. By setting up three columns around the periphery of the stage, a 3D line scan camera is set on each column. During inspection, the three 3D line scan cameras are spaced around the periphery of the cylindrical battery cell, thereby obtaining an image of the entire side of the cylindrical battery cell, reducing the possibility of blind spots that cannot be captured.

[0023] In some embodiments, the cylindricity detection device of the cylindrical battery cell also includes a calibration block, which is used to calibrate the image acquisition system composed of multiple image acquisition devices. The calibration block includes a base plate and two polygonal pyramids, and the bottom surfaces of the two polygonal pyramids are respectively connected to the opposite sides of the base plate.

[0024] By calibrating the coordinate systems of multiple image acquisition devices through a multi-prism, and splicing the coordinate systems of multiple image acquisition devices together, the calibration of the image acquisition system composed of multiple image acquisition devices can be achieved, which can improve the accuracy of image splicing and improve the detection accuracy.

[0025] In some embodiments, the multi-sided platform is a trapezoidal platform, the bottom surface of the trapezoidal platform is connected to the base plate, and the trapezoidal platform includes four inclined side surfaces, wherein the inclined side surfaces of one of the trapezoidal platforms are arranged in parallel with the inclined side surfaces of another trapezoidal platform in a one-to-one correspondence.

[0026] By adopting a trapezoidal stage, the production is convenient, and the torsion angle of the coordinate system can be calibrated through eight parallel oblique side surfaces, thereby improving the calibration accuracy and thus improving the detection accuracy of the subsequent image acquisition device.

[0027] In some embodiments, a lifting module is provided on the bracket, the lifting module is connected to the bracket, and the loading platform is rotatably mounted on the lifting module and can be lifted and lowered along with the lifting module.

[0028] By rotatably installing the stage on the lifting module, the cylindrical battery cell can be rotated to the inspection station by rotating the stage, and then the lifting module is controlled to rise. During the rising process of the lifting module, the encoder sends a photo signal to multiple image acquisition devices to perform image scanning at the same time, which facilitates the image acquisition of the cylindrical battery cell.

[0029] According to some embodiments of the present application, the present application provides a detection method for detecting the cylindricity of a cylindrical battery cell, comprising the following steps:

[0030] Controlling multiple image acquisition devices to take pictures of the cylindrical battery cell to obtain image information of the periphery of the cylindrical battery cell;

[0031] Acquire a 3D image of the periphery of the cylindrical battery cell according to the image information;

[0032] The cylindricity of the cylindrical battery cell is acquired according to the peripheral 3D image.

[0033] By using multiple image acquisition devices to simultaneously obtain image information of the side of the cylindrical battery cell, the cylindricity of the cylindrical battery cell is obtained from the image information through a plug-in built into the industrial computer, filling the gap in the related technology that cannot measure the cylindricity of cylindrical battery cells. In addition, the installation accuracy requirements for the stage and the cylindrical battery cell are low, and the detection efficiency is high.

[0034] In some embodiments, before the step of controlling multiple image acquisition devices to take pictures of the cylindrical battery cell and obtaining image information of the periphery of the cylindrical battery cell, the step further includes:

[0035] controlling the plurality of image acquisition devices to acquire a 3D image of the calibration block;

[0036] Acquire size information of a calibration block according to the 3D image;

[0037] The coordinates and torsion angles of the image acquisition system composed of a plurality of the image acquisition devices are calibrated according to the acquired size information and the standard size of the calibration block.

[0038] By calibrating the coordinate systems of multiple image acquisition devices through the calibration block and splicing the coordinate systems of multiple image acquisition devices together, the coordinate system of the image acquisition system composed of multiple image acquisition devices can be calibrated, which can improve the accuracy of image splicing and improve the detection accuracy.

[0039] In some embodiments, the step of obtaining the cylindricity of the cylindrical battery core according to the peripheral 3D image includes:

[0040] Taking a first preset number of detection surfaces on the peripheral 3D image along the central axis direction of the peripheral 3D image;

[0041] Taking a second preset number of detection points on each of the detection surfaces;

[0042] Constructing a minimum cylindrical surface and a maximum cylindrical surface of the peripheral 3D image according to the detection points;

[0043] The cylindricity of the cylindrical battery cell is obtained according to the difference between the radius of the minimum cylindrical surface and the radius of the maximum cylindrical surface.

[0044] By taking a first preset number of detection surfaces on the peripheral 3D image; taking a second preset number of detection points on each detection surface; constructing the minimum cylindrical surface and the maximum cylindrical surface of the cylindrical battery cell based on the detection points; and obtaining the cylindricity of the cylindrical battery cell based on the difference between the radius of the minimum cylindrical surface and the radius of the maximum cylindrical surface, the cylindricity of the cylindrical battery cell can be easily obtained with high detection accuracy.

[0045] In some embodiments, the step of selecting a first preset number of detection surfaces on the peripheral 3D image along the central axis of the peripheral 3D image includes:

[0046] Three detection surfaces are taken on the peripheral 3D image along the central axis direction of the peripheral 3D image, and the three detection surfaces are respectively located at preset positions of the peripheral 3D image.

[0047] By setting the three detection surfaces at preset positions of the peripheral 3D image, the positions of the detection surfaces can be selected according to actual needs, and targeted detection can be performed on the positions of the cylindrical battery cells that need to be focused on.

[0048] In some embodiments, the step of selecting a first preset number of detection surfaces on the peripheral 3D image along the central axis of the peripheral 3D image includes:

[0049] Three detection surfaces are taken on the peripheral 3D image along the central axis direction of the peripheral 3D image, and the three detection surfaces are respectively located at the top position, the middle position and the bottom position of the peripheral 3D image.

[0050] The first detection surface is selected at the top of the peripheral 3D image, the second detection surface is selected at the middle of the peripheral 3D image, and the third detection surface is selected at the bottom of the peripheral 3D image, so that the selected detection surfaces can cover the cylindrical surface as much as possible.

[0051] In some embodiments, the step of taking a second preset number of detection points on each detection surface includes:

[0052] At least ten detection points are taken on each of the detection surfaces.

[0053] By selecting at least ten detection points on each detection surface, the surface condition of the cylindrical surface can be more comprehensively reflected and the detection accuracy can be improved.

[0054] In some embodiments, the step of taking a second preset number of detection points on each detection surface includes:

[0055] Twelve evenly distributed detection points are taken on each detection surface.

[0056] When the number of selected detection points is twelve, both high detection accuracy and high detection efficiency can be guaranteed.

[0057] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present application. The same reference numerals are used throughout the drawings to represent the same components. In the drawings:

[0059] FIG1 is a schematic structural diagram of a cylindrical battery cell cylindricity detection device according to some embodiments of the present application;

[0060] FIG2 is a schematic diagram of the relative positions of image acquisition devices on the same horizontal plane according to some embodiments of the present application;

[0061] FIG3 is a schematic diagram of the relative position structure of the image acquisition device in the vertical direction according to some embodiments of the present application;

[0062] FIG4 is a side view of a calibration block according to some embodiments of the present application;

[0063] FIG5 is a top view of a calibration block according to some embodiments of the present application;

[0064] FIG6 is a schematic flow chart of the detection method according to the first embodiment of the present application;

[0065] FIG7 is a schematic flow chart of a detection method according to a second embodiment of the present application;

[0066] FIG8 is a schematic flow chart of a detection method according to a third embodiment of the present application;

[0067] FIG9 is a schematic flow chart of a detection method according to a fourth embodiment of the present application;

[0068] FIG10 is a schematic flow chart of a detection method according to a fifth embodiment of the present application;

[0069] FIG11 is a schematic flow chart of a detection method according to a sixth embodiment of the present application;

[0070] FIG12 is a schematic flow chart of a detection method according to a seventh embodiment of the present application;

[0071] FIG13 is a schematic diagram of a peripheral 3D image of a cylindrical battery cell synthesized in some embodiments of the present application, and detection surfaces and detection points selected on the peripheral 3D image.

[0072] The accompanying drawings in the specific implementation manner are as follows:

[0073] Cylindricity detection device 100 for cylindrical battery cells; bracket 101, mounting column 1011; column 1012; connecting plate 1013; stage 102, image acquisition device 103, lifting module 104; 1031, laser scanner

[0074] Cylindrical cell 200; standard block 300; bottom plate 301; polygonal platform 302; trapezoidal platform 303; oblique side surface 3031; first side surface 3031a; second side surface 3031b; top surface 3032; bottom surface 3033; peripheral 3D image 400; first detection surface 401; second detection surface 402; third detection surface 403; detection point 404. DETAILED DESCRIPTION

[0075] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0076] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0077] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

[0078] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0079] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0080] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0081] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0082] In the description of the embodiments of this application, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connect," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the embodiments of this application based on specific circumstances.

[0083] Currently, market developments indicate that power batteries are becoming increasingly widely used. They are not only used in energy storage systems such as hydropower, thermal, wind, and solar power plants, but are also widely used in electric vehicles like electric bicycles, electric motorcycles, and electric vehicles, as well as in military equipment and aerospace. As power battery applications continue to expand, market demand is also growing.

[0084] In the field of lithium batteries, the control over battery cell size is becoming increasingly strict. Due to the complexity of cylindrical surface imaging, it is relatively difficult to monitor the cylindricity of cylindrical batteries. Therefore, there is no good way to detect the cylindricity of cylindrical batteries. Cylindricity is precisely the most important parameter that can reflect the cylindrical shape of cylindrical batteries. In related technologies, only a profilometer can be used to obtain the diameter of the cylindrical battery cell through multi-angle measurement, thereby indirectly achieving the purpose of battery cell cylindricity monitoring. However, this measurement method is not a direct measurement of cylindricity and cannot accurately measure the cylindricity of cylindrical batteries.

[0085] The battery cells disclosed in the embodiments of the present application can be used in electrical devices that use batteries as power sources or various energy storage systems that use batteries as energy storage elements. Electrical devices can include, but are not limited to, mobile phones, tablets, laptops, electric toys, power tools, battery-powered vehicles, electric vehicles, ships, spacecraft, and the like. Electric toys can include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, and spacecraft can include airplanes, rockets, space shuttles, and spacecraft, among others.

[0086] 1 , according to some embodiments of the present application, the present application provides a cylindrical battery cell cylindricity detection device 100, comprising a bracket 101, a stage 102 mounted on the bracket 101, and a plurality of image acquisition devices 103 respectively mounted on the bracket 101; the stage 102 is used to load the cylindrical battery cell; the plurality of image acquisition devices 103 are used to acquire image information of the cylindrical battery cell, so as to construct a cylindrical surface based on the image information, and to acquire the cylindricity of the cylindrical battery cell 200 based on the constructed cylindrical surface. The stage 102 is used to load the cylindrical battery cell 200, and the bracket 101 is equipped with multiple image acquisition devices 103. The multiple image acquisition devices 103 are respectively arranged around the side of the cylindrical battery cell 200, and are used to simultaneously photograph (or scan) the cylindrical battery cell 200 from various directions of the side of the cylindrical battery cell 200 to obtain image information of the side of the cylindrical battery cell 200. The cylindrical battery cell cylindricity detection device 100 can also include an industrial computer, and then the collected side image information is processed by a plug-in built into the industrial computer to construct multiple virtual cylindrical surfaces. The cylindricity of the cylindrical battery cell 200 can be obtained based on the constructed multiple virtual cylindrical surfaces.

[0087] It should also be noted that the embodiment of the present application uses multiple image acquisition devices 103 to scan the side of the cylindrical battery cell 200 from various directions, and can simultaneously obtain image information of the side from various directions. If a single image acquisition device 103 is used to obtain image information of the side from various directions by controlling the rotation of the cylindrical battery cell 200, the relative angle rotation between the stage 102 and the cylindrical battery cell 200 may cause detection errors, and the installation precision of the stage 102 and the cylindrical battery cell 200 is required to be higher, the image acquisition time is longer, and the detection efficiency is low.

[0088] By providing a stage for placing the cylindrical battery cell 200 and employing multiple image acquisition devices 103 to scan the cylindrical battery cell 200 from various directions around its lateral periphery, image information from all directions of the lateral periphery can be simultaneously obtained. A cylindrical surface can be constructed based on the image information, and the cylindricity of the cylindrical battery cell 200 can be determined based on the constructed cylindrical surface. This embodiment has the advantages of being able to directly detect the cylindricity of the cylindrical battery cell 200 and providing accurate measurement results.

[0089] 1 , in some embodiments, a plurality of image acquisition devices 103 are evenly distributed along the circumference of the cylindrical battery cell 200 .

[0090] The multiple image acquisition devices 103 are evenly distributed along the circumference of the cylindrical battery cell 200. The image acquisition range of the multiple image acquisition devices 103 covers the entire circumference of the cylindrical battery cell 200, ensuring that image information of any part of the periphery of the cylindrical battery cell 200 is not missed, and the number of image acquisition devices 103 can be reduced.

[0091] By evenly distributing the plurality of image acquisition devices 103 along the circumference of the cylindrical battery cell 200 , the entire circumference of the cylindrical battery cell 200 can be covered, and the number of image acquisition devices 103 can be reduced, thereby lowering the manufacturing cost.

[0092] 1 and 2 , in some embodiments, a plurality of image acquisition devices 103 are spaced apart and distributed along the central axis of the cylindrical battery cell 200 .

[0093] The cylindrical battery cell 200 is cylindrical in shape, and the central axis refers to the central axis of the cylindrical shape corresponding to the cylindrical battery cell 200. Spacing refers to the multiple image acquisition devices 103 being located at different heights along the central axis of the cylindrical battery cell. In further embodiments, the multiple image acquisition devices 103 are staggered along the circumference of the cylindrical battery cell 200. The cylindrical battery cell 200 can be mounted on the stage 102 in various configurations, such as vertically or horizontally. Regardless of the configuration, the multiple image acquisition devices 103 are spaced apart along the central axis of the cylindrical battery cell 200, that is, spaced apart along the height of the cylindrical surface of the cylindrical battery cell 200. Specifically, referring to FIG3 , arrow H in FIG3 represents the ascending direction of the cylindrical battery cell 200, and label L represents the vertical offset distance between two adjacent image acquisition devices 103. In one embodiment, the vertical offset distance between two adjacent image acquisition devices 103 is 8 mm to 12 mm. Theoretically, the greater the vertical offset distance of the image acquisition devices 103, the smaller the laser interference effect between different image acquisition devices 103 will be. However, if the distance between the image acquisition devices 103 is too large, the lifting module 104 will drive the cylindrical battery cell 200 to move a longer distance, affecting the detection efficiency. Therefore, the offset distance needs to be set within a certain range. After practical confirmation, it has been found that when the offset distance is set above 8mm, the image is clearer, and when it is set below 12mm, the detection efficiency is not significantly affected. Therefore, in this embodiment, the vertical offset distance of two adjacent image acquisition devices 103 is set to 8mm to 12mm. Furthermore, when the interval offset distance is set to above 10mm, the image is clearer, so the vertical offset distance of two adjacent image acquisition devices 103 can also be set to 10mm to 12mm.

[0094] By distributing the image acquisition devices 103 at intervals along the central axis of the cylindrical battery cell 200, mutual interference between the laser beams emitted by the laser scanners 1031 of the image acquisition devices 103 can be reduced, ensuring effective imaging and obtaining clear images, facilitating subsequent image processing. Furthermore, a minimal number of image acquisition devices 103 can be used to provide comprehensive coverage of the cylindrical surface of the cylindrical battery cell 200. This ensures detection accuracy while reducing the number of image acquisition devices 103 and lowering the manufacturing cost and computational complexity of the cylindrical battery cell cylindricity detection device 100.

[0095] In some embodiments, multiple image acquisition devices 103 take photos of the cylindrical battery cell 200 to obtain image information, obtain a peripheral 3D image 400 of the cylindrical battery cell 200 based on the image information, and take a first preset number of detection surfaces at preset positions on the peripheral 3D image 400, take a second preset number of detection points 404 on each detection surface, and obtain the cylindricity of the cylindrical battery cell 200 based on the difference in radius of the cylindrical surface constructed by the detection points 404 on each detection surface.

[0096] Specifically, multiple image acquisition devices 103 are controlled to photograph the cylindrical battery cell 200 and obtain image information of the periphery of the cylindrical battery cell 200. A plug-in is provided in the industrial computer. The plug-in obtains the image information captured by each image acquisition device 103 and, through splicing or otherwise, obtains a 3D image of the periphery of the cylindrical battery cell 200. The image acquisition device 103 has a built-in preset program. Through the preset program, a first preset number of detection surfaces are selected on the periphery 3D image 400. The detection surfaces are cross-sections of the 3D image of the cylindrical battery cell 200. Several cross-sections are selected from the 3D image as detection objects. The intersection of the detection surface and the 3D image of the cylindrical battery cell 200 forms a circle. This circle is also a circle on the cylindrical battery cell 200. A second preset number of detection points 404 are selected on the circle. A standard circle is fitted based on the second preset number of detection points 404 taken from each detection surface, and the center of the standard circle is obtained. The distances between the center of the circle and each test point 404 on the same test surface are measured. The three points with the smallest distances and the three points with the largest distances are taken to form a circle. The three points with the smallest distances form the innermost circle, and the three points with the largest distances form the outermost circle. The innermost circles obtained on each test surface are used to form a cylindrical surface to obtain the minimum cylindrical surface. The outermost circles obtained on all test surfaces are used to form a cylindrical surface to obtain the maximum cylindrical surface. The radii of the minimum cylindrical surface and the maximum cylindrical surface are respectively obtained. The difference between the two radii is used to obtain the cylindricity of the cylindrical battery cell 200.

[0097] The cylindrical battery cell 200 is photographed by multiple image acquisition devices 103 to obtain image information, a peripheral 3D image 400 of the cylindrical battery cell 200 is obtained based on the image information, and the cylindricity of the cylindrical battery cell 200 is obtained through a preset program of the image acquisition device 103. The cylindricity of the cylindrical battery cell 200 can be directly obtained with high detection accuracy.

[0098] 1 and 2 , in some embodiments, the image acquisition device 103 includes three 3D line scan cameras respectively mounted on the bracket 101 , the three 3D line scan cameras are spaced apart along the periphery of the cylindrical battery cell 200 , and the three 3D line scan cameras are spaced apart along the central axis direction of the cylindrical battery cell 200 .

[0099] 3D line scan cameras can generate laser images. Their operating principle is to scan an object with a laser line and convert the reflected signal from the laser line into a digital signal, thereby obtaining the object's three-dimensional shape. Generally speaking, the three 3D line scan cameras are arranged in a spiral along the central axis of the cylindrical battery cell 200. The cylindrical battery cell 200 is cylindrical, and the central axis refers to the central axis of the cylinder corresponding to the cylindrical battery cell 200. Spacing refers to the multiple image acquisition devices 103 being located at different heights along the central axis of the cylindrical battery cell 200. In further embodiments, the vertical offset distance between two adjacent image acquisition devices 103 can be set to 8mm to 12mm. The three 3D line scan cameras are spaced apart along the circumference of the cylindrical battery cell 200. Referring to Figure 2, the projection plane is defined as the plane perpendicular to the central axis of the cylindrical battery cell 200, and the projection of the central axis of the cylindrical battery cell 200 onto the projection plane is defined as the center of the circle. The projections of the three 3D line scan cameras on the projection plane are evenly distributed around the center of the circle. In a further embodiment, three 3D line scan cameras are evenly distributed along the outer circumference of the cylindrical battery cell 200, that is, two adjacent 3D line scan cameras are projected onto the projection surface at an angle of 120 degrees. Of course, the number of 3D line scan cameras can also be four.

[0100] By distributing three 3D line scan cameras at intervals along the outer circumference of the cylindrical cell 200, images of the entire side of the cylindrical cell in all directions can be captured while ensuring detection accuracy. This reduces the number of image acquisition devices 103, lowering the manufacturing cost and computational complexity of the cylindrical cell cylindricity detection device 100. By distributing the image acquisition devices 103 at intervals along the central axis of the cylindrical cell 200, mutual interference between the laser beams emitted by the laser scanners 1031 of the image acquisition devices 103 can be reduced, ensuring clear images of the entire side of the cylindrical cell 200 in all directions, facilitating subsequent processing of the captured images.

[0101] In some embodiments, the bracket 101 includes a mounting column 1011 and three columns 1012 . The stage 102 is mounted on the mounting column 1011 . The three columns 1012 are arranged around the periphery of the stage 102 . The three 3D line scan cameras are mounted on the three columns 1012 in a one-to-one correspondence.

[0102] Specifically, the mounting column 1011 and the three columns 1012 are all arranged vertically and can be placed on a table when in use. A connecting plate 1013 can also be provided, and the connecting plate 1013 is connected to the top of the three columns 1012, so that the three columns 1012 are connected as a whole. The three 3D line scan cameras are installed on the three columns 1012 in a one-to-one correspondence, which means that each column 1012 is provided with a 3D line scan camera. Since the cylindrical battery cell 200 is placed on the stage 102, the three columns 1012 are arranged around the periphery of the stage 102, so that the 3D line scan cameras installed on the columns 1012 can be distributed around the periphery of the cylindrical battery cell 200, thereby being able to obtain an image of the entire side of the cylindrical battery cell 200. Of course, the 3D line scan camera can also be arranged to be slidably mounted on the column 1012, so that the position of the 3D line scan camera on the column 1012 can be adjusted to adapt to the measurement of cylindrical battery cells 200 of different heights.

[0103] By providing a mounting post 1011, a mounting position is provided for the stage 102. By providing three upright posts 1012 around the periphery of the stage 102, each upright post 1012 is provided with a 3D line scan camera. When inspecting, the three 3D line scan cameras are spaced apart around the periphery of the cylindrical cell 200, thereby being able to obtain an image of the entire side of the cylindrical cell 200, reducing the possibility of blind spots on the side that cannot be captured. Referring to Figure 1, according to some embodiments of the present application, a lifting module 104 is provided on the bracket 101, and the lifting module 104 is connected to the bracket 101. The stage 102 is rotatably mounted on the lifting module 104 and can be raised and lowered with the lifting module 104.

[0104] The lifting module 104 can move vertically on the bracket 101, thereby driving the stage 102 on the lifting module 104 to move upward and downward, transporting the cylindrical battery cell 200 to the scanning position of the image acquisition device 103. During the movement, the encoder on the lifting module 104 sends a photo signal to multiple image acquisition devices 103 for simultaneous image scanning. Multiple mounting positions can be set on the stage 102, and a cylindrical battery cell 200 can be placed on each mounting position. When a cylindrical battery cell 200 needs to be inspected, the cylindrical battery cell 200 to be inspected is rotated by rotating the stage 102 to reach the inspection position, and then follows the lifting module 104 to make vertical movement for scanning by the image acquisition device 103. After the scan is completed, the cylindrical battery cell 200 returns to the inspection position under the movement of the lifting module 104 and is then removed. Of course, the stage 102 may also be able to move vertically on the lifting module 104 to transport the cylindrical battery cell 200 to the scanning area of ​​the image acquisition device 103. Specifically, the lifting module 104 may be installed on the installation column 1011.

[0105] By rotatably mounting the stage 102 on the lifting module 104, the cylindrical battery cell 200 can be rotated to the inspection station by rotating the stage 102, and then the lifting module 104 is controlled to rise. During the rising process of the lifting module 104, the encoder sends a photo signal to multiple image acquisition devices 103 to perform image scanning simultaneously, which facilitates image acquisition of the cylindrical battery cell 200.

[0106] 4 and 5 , in some embodiments, the cylindrical battery cell cylindricity detection device 100 further includes a calibration block 300 , which is used to calibrate the image acquisition system composed of multiple image acquisition devices 103 . The calibration block 300 includes a base plate 301 and two polygonal pyramids 302 , wherein the bottom surfaces 3033 of the two polygonal pyramids 302 are respectively connected to opposite sides of the base plate 301 .

[0107] The polygonal pyramid 302 includes a top surface 3032, a bottom surface 3033 opposite to the top surface 3032, and a plurality of oblique side surfaces 3031 disposed between the top surface 3032 and the bottom surface 3033. The top surface 3032 and the bottom surface 3033 of the polygonal pyramid 302 are disposed parallel to each other. After the bottom surfaces 3033 of two identical polygonal pyramids 302 are respectively connected to opposite sides of the base plate 301, the oblique side surfaces 3031 corresponding to the two polygonal pyramids 302 are disposed parallel to each other. As shown in FIG4 , the oblique side surfaces 3031 include at least a first side surface 3031a and a second side surface 3031b. The two first side surfaces 3031a of the two polygonal pyramids 302 are disposed parallel to each other, and the two second side surfaces 3031b of the two polygonal pyramids 302 are disposed parallel to each other. A calibration block 300 is used to calibrate a system composed of multiple image acquisition devices 103. Specifically, referring to Figures 4 and 5 , the X, Y, and Z coordinates of the image acquisition device 103 are calibrated using the length D and width F of the top surface 3032 of the polygonal pyramid 302, the height C of the polygonal pyramid 302, the height B of the base plate 301, the length E of the base plate 301, and the width A of the base plate 301. The distance between the mutually parallel oblique side surfaces 3031 of the polygonal pyramid 302 of the calibration block 300 is used to calibrate the torsion angle of the coordinate system of the image acquisition system composed of multiple image acquisition devices 301. Of course, blind holes can also be provided in the base plate 301 to secure the calibration block 300 during calibration.

[0108] The coordinate systems of the multiple image acquisition devices 103 are calibrated by the polygonal table 302, and the coordinate systems of the multiple image acquisition devices 103 are spliced ​​together to achieve calibration of the image acquisition system composed of the multiple image acquisition devices 103, which can improve the accuracy of image splicing and improve the detection accuracy.

[0109] 4 and 5 , in some embodiments, the multi-sided platform 302 is a trapezoidal platform 303, the bottom surface 3033 of the trapezoidal platform 303 being connected to the base plate 301. The trapezoidal platform 303 includes four oblique side surfaces 3031, wherein the oblique side surfaces 3031 of one trapezoidal platform 303 are arranged parallel to the oblique side surfaces 3031 of another trapezoidal platform 303. Specifically, the trapezoidal platform 303 can be an isosceles trapezoidal platform. In this way, the bottom surface 3033 of the trapezoidal platform 303 is connected to the base plate 301, and the four oblique side surfaces 3031 of the trapezoidal platform 303 are arranged parallel to each other. The eight oblique side surfaces 3031 can be used to calibrate the torsion angle of the coordinate system of the image acquisition system composed of multiple image acquisition devices 301, thereby improving detection accuracy.

[0110] The trapezoidal stage 303 is easy to manufacture and can calibrate the torsion angle of the coordinate system through eight parallel inclined side surfaces 3031 , thereby improving the calibration accuracy and the detection accuracy of the subsequent image acquisition device 103 .

[0111] According to some embodiments of the present application, the present application provides a cylindricity detection device 100 for a cylindrical battery cell, comprising a bracket 101, a lifting module 104 and a loading platform 102; the lifting module 104 is connected to the bracket 101, the loading platform 102 is rotatably mounted on the lifting module 104 and can be lifted and lowered with the lifting module 104, and the loading platform 102 is used to load a cylindrical battery cell 200; three image acquisition devices 103 are provided on the bracket 101, and the image acquisition devices 103 are staggered along the central axis direction of the cylindrical battery cell; the three image acquisition devices 103 are used to take pictures to obtain image information of the cylindrical surface of the cylindrical battery cell 200. Specifically, the three image acquisition devices 103 respectively take pictures of the cylindrical battery cell 200 from the side of the cylindrical battery cell 200 to obtain pictures of the cylindrical battery cell 200 at various angles. The plug-in synthesizes and splices the pictures to obtain a peripheral 3D image 400 of the cylindrical battery cell 200. Then, multiple detection surfaces are selected on the peripheral 3D image 400 of the cylindrical battery cell 200, and multiple detection points are taken on each detection surface. The minimum cylindrical surface and the maximum cylindrical surface are constructed according to all the detection points on all the selected detection surfaces. The minimum cylindrical surface refers to the cylindrical surface with the smallest radius, and the maximum cylindrical surface refers to the cylindrical surface with the largest radius. The difference between the radius of the maximum cylindrical surface and the minimum cylindrical surface is the cylindricity of the cylindrical battery cell 200. The three image acquisition devices 103 are evenly spaced on the projection of the horizontal plane, and can complete the coverage of the outer surface of the cylindrical battery cell 200 without blind spots with a minimum number of image acquisition devices 103. This can not only ensure the accuracy of detection, but also reduce the number of image acquisition devices 103, that is, reduce the production cost and calculation difficulty of the cylindrical battery cell cylindricity detection device 100.

[0112] In the second aspect, referring to FIG6 , FIG6 is a flow chart of the detection method of the first embodiment of the present application. According to some embodiments of the present application, the present application provides a detection method, which is applied to the aforementioned cylindrical battery cell cylindricity detection device 100, and is used to detect the cylindricity of the cylindrical battery cell 200. The cylindrical battery cell cylindricity detection device 100 includes a bracket 101, a lifting module 104 and a loading platform 102; the lifting module 104 is connected to the bracket 101, and the loading platform 102 is rotatably mounted on the lifting module 104 and can be lifted and lowered with the lifting module 104. The loading platform 102 is used to load the cylindrical battery cell 200; three image acquisition devices 103 are provided on the bracket 101, and the image acquisition devices 103 are staggered in the vertical direction; the three image acquisition devices 103 are used to take pictures to obtain image information of the cylindrical surface of the cylindrical battery cell 200, including the following steps:

[0113] S10, controlling the plurality of image acquisition devices 103 to take pictures of the cylindrical battery cell 200 to obtain image information of the periphery of the cylindrical battery cell 200;

[0114] First, a cylindrical battery cell 200 is placed on the stage 102. Driven by the lifting module 104, the cylindrical battery cell 200 rises. Multiple image acquisition devices 103 disposed around the cylindrical battery cell 200 simultaneously capture image information of the cylindrical battery cell 200 from all directions around the cylindrical battery cell 200.

[0115] S20, obtaining a peripheral 3D image 400 of the cylindrical battery cell 200 according to the image information;

[0116] The industrial computer is provided with a plug-in, which obtains the image information captured by each image acquisition device 103 and obtains a 3D image of the periphery of the cylindrical battery cell 200 through splicing or other means;

[0117] S30 , obtaining the cylindricity of the cylindrical battery cell 200 according to the peripheral 3D image 400 .

[0118] The cylindricity of the cylindrical battery cell 200 can be obtained based on the peripheral 3D image and the preset program built into the image acquisition device 103 .

[0119] By using multiple image acquisition devices 103 to simultaneously acquire image information of the side of the cylindrical battery cell 200, and using a plug-in of an industrial computer to obtain the acquired image information, the cylindricity of the cylindrical battery cell 200 is obtained, which fills the gap in the related art that the cylindricity of the cylindrical battery cell 200 cannot be measured. In addition, the installation accuracy requirements for the stage 102 and the cylindrical battery cell 200 are low, and the detection efficiency is high.

[0120] 7 , which is a flow chart of a detection method according to a second embodiment of the present application, further includes the following steps after step S10 and before step S30 :

[0121] S101, controlling multiple image acquisition devices to acquire a 3D image of a calibration block;

[0122] Multiple image acquisition devices 103 take photos of the cylindrical battery cell 200 to obtain image information of the periphery of the cylindrical battery cell 200. A plug-in is provided in the industrial computer to obtain the image information taken by each image acquisition device 103 and obtain a 3D image of the periphery of the cylindrical battery cell 200 through splicing;

[0123] S102, obtaining size information of the calibration block according to the 3D image;

[0124] The dimensional information of the calibration block in all directions can be measured based on the acquired 3D image. Specifically, the calibration block includes a base plate and two polygonal pyramids, the polygonal pyramid 302 is a trapezoidal platform 303, the bottom surface 3033 of the trapezoidal platform 303 is connected to the base plate 301, and the trapezoidal platform 303 includes four oblique side surfaces 3031, wherein the oblique side surfaces 3031 of one trapezoidal platform 303 are arranged in parallel with the oblique side surfaces 3031 of another trapezoidal platform 303. The polygonal pyramid 302 includes a top surface 3032, a bottom surface 3033 arranged opposite to the top surface 3032, and a plurality of oblique side surfaces 3031 arranged between the top surface 3032 and the bottom surface 3033. Referring to Figures 4 and 5, the dimensional information includes the length D and width F of the top surface 3032 of the polygonal pyramid 302, the height C of the polygonal pyramid 302, the height B of the base plate 301, the length E of the base plate 301, and the width A of the base plate 301.

[0125] S103 calibrates the coordinates and torsion angles of the image acquisition system composed of multiple image acquisition devices based on the acquired dimensional information and the standard dimensions of the calibration block. The standard dimensions refer to the dimensions of the calibration block measured using other calibrated image acquisition devices, i.e., the actual dimensions of the calibration block. Comparing the acquired dimensional information with the standard dimensions of the calibration block allows calibration of the X, Y, and Z coordinates of the image acquisition devices and the torsion angle of the coordinate system.

[0126] In the above embodiment of the present invention, the coordinate systems of multiple image acquisition devices 103 are calibrated by the calibration block 303, and the coordinate systems of the multiple image acquisition devices 103 are spliced ​​together to achieve calibration of the coordinate system of the image acquisition system composed of the multiple image acquisition devices 103, which can improve the accuracy of image splicing and improve the detection accuracy.

[0127] It should be noted that the calibration step using the calibration block 300 can be performed only when needed, such as when the instrument is first used or the image acquisition device 103 is replaced, and does not need to be used in every detection.

[0128] 8 , which is a flow chart of a detection method according to a third embodiment of the present application, step S30 includes:

[0129] S301, selecting a first preset number of detection surfaces on the peripheral 3D image 400 along the central axis of the peripheral 3D image 400;

[0130] With reference to FIG13 , FIG13 is a schematic diagram of a synthesized peripheral 3D image of a cylindrical battery cell cylindricity detection device according to some embodiments of the present application, and detection surfaces and detection points selected on the peripheral 3D image. The outer dotted line in FIG13 represents the synthesized peripheral 3D image 400 of the cylindrical battery cell 200, the circle filled with slashes represents the selected detection surface, and the solid point on each detection surface represents the detection point 404 selected on each detection surface. The detection surface here is a cross-section of the peripheral 3D image 400 of the cylindrical battery cell 200. Several cross-sections are selected as detection objects on the 3D image, and the first preset number here can be set according to actual needs.

[0131] S302, taking a second preset number of detection points 404 on each detection surface;

[0132] Specifically, the detection surface intersects the 3D image of the cylindrical battery cell 200 to form a circle, which is also a circle on the cylindrical battery cell 200. A second preset number of detection points 404 are taken on the circle, where the second preset number can be set according to actual needs.

[0133] S303, constructing the minimum cylindrical surface and the maximum cylindrical surface of the cylindrical battery cell 200 according to the detection point 404;

[0134] Specifically, a standard circle is fitted based on the second preset number of detection points 404 taken from each detection surface, and the center of the standard circle is obtained. The distance between the center of the circle and each detection point 404 on the same detection surface is measured respectively, and the three points with the smallest distance and the three points with the largest distance are taken to form a circle. The three points with the smallest distance form a circle to obtain the innermost circle, and the three points with the longest distance form a circle to obtain the outermost circle. The innermost circle obtained on each detection surface is used to form a cylindrical surface to obtain the smallest cylindrical surface; the outermost circle obtained on all detection surfaces is used to form a cylindrical surface to obtain the largest cylindrical surface.

[0135] S304 : Obtain the cylindricity of the cylindrical battery cell 200 according to the difference between the radius of the smallest cylindrical surface and the radius of the largest cylindrical surface.

[0136] The radius of the minimum cylindrical surface and the radius of the maximum cylindrical surface are obtained respectively, and the difference obtained by subtracting the two radii is used to obtain the cylindricity of the cylindrical battery cell 200.

[0137] By taking a first preset number of detection surfaces on the peripheral 3D image 400; taking a second preset number of detection points 404 on each detection surface; constructing the minimum cylindrical surface and the maximum cylindrical surface of the cylindrical battery cell 200 based on the detection points 404; and obtaining the cylindricity of the cylindrical battery cell 200 based on the difference between the radius of the minimum cylindrical surface and the radius of the maximum cylindrical surface, the cylindricity of the cylindrical battery cell 200 can be easily obtained with high detection accuracy.

[0138] 9 , which is a flow chart of a detection method according to a fourth embodiment of the present application, step S301 includes:

[0139] S3011 , three detection surfaces are selected on the peripheral 3D image 400 along the central axis of the peripheral 3D image 400 , and the three detection surfaces are respectively located at preset positions of the peripheral 3D image 400 .

[0140] The preset position here may be a position of the peripheral 3D image 400 determined in advance. If it is necessary to focus on detecting a part of the position of the cylindrical battery cell, the corresponding position may be selected as the preset position.

[0141] 10 and 13 , FIG. 10 is a flow chart of a detection method according to a fifth embodiment of the present application. Specifically, step S301 includes step S3012,

[0142] Three detection surfaces are taken on the peripheral 3D image 400 along the central axis direction of the peripheral 3D image 400 , and the three detection surfaces are respectively located at preset positions of the peripheral 3D image 400 .

[0143] Specifically, the three detection surfaces include a first detection surface 401, a second detection surface 402 and a third detection surface 403; wherein the first detection surface 401 is located at the top position of the peripheral 3D image 400, the second detection surface 402 is located in the middle position of the peripheral 3D image 400, and the third detection surface 403 is located at the bottom position of the peripheral 3D image 400.

[0144] The 3D image of the cylindrical battery cell 200 is a cylindrical surface. Three detection surfaces are sequentially selected along the height direction of the cylindrical surface, namely the first detection surface 401, the second detection surface 402, and the third detection surface 403. The first detection surface 401 is selected to be located at the top of the peripheral 3D image 400, the second detection surface 402 is located in the middle of the peripheral 3D image 400, and the third detection surface 403 is located at the bottom of the peripheral 3D image 400. This allows the selected detection surfaces to cover the cylindrical surface as much as possible. Of course, to improve detection accuracy, a larger number of detection surfaces can also be selected, and those skilled in the art can set them according to actual needs.

[0145] 11 , which is a flow chart of a detection method according to a sixth embodiment of the present application, step S302 includes:

[0146] S3021, take at least ten detection points 404 on each detection surface.

[0147] The number of detection points 404 cannot be too small. If it is too small, the concave or convex parts of the cylindrical surface may not be selected, thereby reducing the detection accuracy. In theory, the more detection points 404 selected, the better. The more detection points 404 selected, the higher the measurement accuracy. Therefore, the number of detection points 404 selected should not be less than ten.

[0148] By selecting at least ten detection points on each detection surface, the surface condition of the cylindrical surface can be more comprehensively reflected and the detection accuracy can be improved.

[0149] 12 , which is a flow chart of a detection method according to a seventh embodiment of the present application, step S302 includes:

[0150] S3022, select twelve evenly distributed detection points 404 on each detection surface.

[0151] While theoretically, the more detection points 404 selected, the better, and the more detection points 404 selected, the higher the measurement accuracy, the more points selected, the greater the computational effort, which can affect detection efficiency. Experiments have shown that selecting twelve detection points 404 achieves both high detection accuracy and high detection efficiency.

[0152] According to some embodiments of the present application, first, the cylindrical battery cell 200 is placed on the stage 102. Under the action of the lifting module 104, the cylindrical battery cell 200 rises, and multiple image acquisition devices 103 arranged on the periphery of the cylindrical battery cell 200 obtain image information of the side of the cylindrical battery cell 200 from various directions of the side of the cylindrical battery cell 200; a plug-in is provided in the industrial computer, and the plug-in obtains the image information taken by each image acquisition device 103, and obtains a 3D image of the periphery of the cylindrical battery cell 200 after splicing; a calibration block 300 is used to calibrate the cylindrical battery cell 200. Multiple image acquisition devices 103 are calibrated; a first detection surface 401, a second detection surface 402, and a third detection surface 403 are spaced apart on the peripheral 3D image 400 along the central axis of the peripheral 3D image 400; wherein the first detection surface 401 is located at the top of the peripheral 3D image 400, the second detection surface 402 is located in the middle of the peripheral 3D image 400, and the third detection surface 403 is located at the bottom of the peripheral 3D image 400; twelve detection points 404 are evenly distributed on each detection surface. Based on the detection points 404, the minimum cylindrical surface and the maximum cylindrical surface of the cylindrical battery cell 200 are constructed; and the cylindricity of the cylindrical battery cell 200 is obtained based on the difference between the radius of the minimum cylindrical surface and the radius of the maximum cylindrical surface. By using multiple image acquisition devices 103 to simultaneously acquire image information of the side of the cylindrical battery cell 200, and using a plug-in built into the industrial computer to obtain the acquired image information, the cylindricity of the cylindrical battery cell 200 is obtained, filling the gap in the related art that cannot measure the cylindricity of the cylindrical battery cell 200, and the installation accuracy requirements for the stage 102 and the cylindrical battery cell 200 are low, and the detection efficiency is high.

[0153] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A cylindrical battery cell cylindricity detection device, wherein: include: Bracket; A loading platform, the loading platform is mounted on the bracket, and the loading platform is used to load cylindrical batteries; A plurality of image acquisition devices are installed on the bracket; the plurality of image acquisition devices are used to acquire image information of the cylindrical battery cell, to construct a cylindrical surface according to the image information, and to acquire the cylindricity of the cylindrical battery cell according to the constructed cylindrical surface.

2. The cylindrical battery cell cylindricity detection device according to claim 1, wherein: The plurality of image acquisition devices are evenly distributed along the outer circumference of the cylindrical battery core.

3. The cylindricality detection device of a cylindrical battery cell according to claim 1, wherein: The plurality of image acquisition devices are distributed at intervals along the central axis direction of the cylindrical battery core.

4. The cylindricality detection device of a cylindrical battery cell according to claim 1, wherein: The multiple image acquisition devices are used to take pictures of the cylindrical battery cell to obtain image information, so as to obtain a peripheral 3D image of the cylindrical battery cell according to the image information, and take a first preset number of detection surfaces at preset positions on the peripheral 3D image, take a second preset number of detection points on each of the detection surfaces, construct a cylindrical surface according to the detection points on each of the detection surfaces, and obtain the cylindricity of the cylindrical battery cell according to the difference in the radii of the constructed cylindrical surfaces.

5. The cylindricality detection device of a cylindrical battery cell according to claim 1, wherein: The multiple image acquisition devices include three 3D line scan cameras respectively installed on the bracket, the three 3D line scan cameras are evenly distributed along the outer circumference of the cylindrical battery core, and the three 3D line scan cameras are spaced apart along the central axis direction of the cylindrical battery core.

6. The cylindricality detection device for a cylindrical battery cell according to claim 5, wherein: The bracket includes a mounting column and three upright columns, the stage is mounted on the mounting column, the three upright columns are arranged around the periphery of the stage, and the three 3D line scan cameras are mounted on the three upright columns in a one-to-one correspondence.

7. The cylindricality detection device for a cylindrical battery cell according to any one of claims 1 to 6, wherein: The cylindrical battery cell cylindricity detection device also includes a calibration block, which is used to calibrate the image acquisition system composed of multiple image acquisition devices. The calibration block includes a base plate and two polygonal pyramids, and the bottom surfaces of the two polygonal pyramids are respectively connected to the opposite sides of the base plate.

8. The cylindrical battery cell cylindricity detection device according to claim 7, wherein: The multi-sided platform is a trapezoidal platform, the bottom surface of which is connected to the bottom plate, and the trapezoidal platform includes four inclined side surfaces, wherein the inclined side surfaces of one of the trapezoidal platforms are arranged in parallel with the inclined side surfaces of another of the trapezoidal platforms in one-to-one correspondence.

9. The cylindricality detection device for a cylindrical battery cell according to any one of claims 1 to 6, wherein: The bracket is provided with a lifting module, the lifting module is connected to the bracket, and the loading platform is rotatably mounted on the lifting module and can be lifted and lowered along with the lifting module.

10. A detection method for detecting the cylindricity of a cylindrical battery cell, wherein: The following steps are involved: Controlling multiple image acquisition devices to take photos of the cylindrical battery cell to obtain image information of the periphery of the cylindrical battery cell; Acquire a peripheral 3D image of the cylindrical battery cell according to the image information; The cylindricity of the cylindrical battery core is acquired according to the peripheral 3D image.

11. The detection method according to claim 10, wherein: Before the step of controlling a plurality of image acquisition devices to take photos of the cylindrical battery cell to obtain image information of the periphery of the cylindrical battery cell, the step further includes: Controlling the plurality of image acquisition devices to acquire a 3D image of the calibration block; Acquire size information of the calibration block according to the 3D image; The coordinates and torsion angles of the image acquisition system composed of a plurality of the image acquisition devices are calibrated according to the acquired size information and the standard size of the calibration block.

12. The detection method according to claim 10 or 11, wherein: The step of acquiring the cylindricity of the cylindrical battery core according to the peripheral 3D image comprises: Taking a first preset number of detection surfaces on the peripheral 3D image along the central axis direction of the peripheral 3D image; Taking a second preset number of detection points on each of the detection surfaces; Constructing a minimum cylindrical surface and a maximum cylindrical surface of the peripheral 3D image according to the detection points; The cylindricity of the cylindrical battery cell is obtained according to the difference between the radius of the minimum cylindrical surface and the radius of the maximum cylindrical surface.

13. The detection method according to claim 12, wherein: The step of taking a first preset number of detection surfaces on the peripheral 3D image along the central axis direction of the peripheral 3D image comprises: Three detection surfaces are taken on the peripheral 3D image along the central axis direction of the peripheral 3D image, and the three detection surfaces are respectively located at preset positions of the peripheral 3D image.

14. The detection method according to claim 13, wherein: The three detection surfaces are respectively located at the top, middle and bottom of the peripheral 3D image.

15. The detection method according to claim 14, wherein: The step of taking a second preset number of detection points on each detection surface comprises: At least ten detection points are taken on each of the detection surfaces.

16. The detection method according to claim 15, characterized in that: The step of taking a second preset number of detection points on each detection surface comprises: Twelve evenly distributed detection points are taken on each detection surface.

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