KR20230067468A - Welding inspection apparatus - Google Patents

Abstract

In the present invention, in a tabless cylindrical battery cell including a jelly roll type electrode assembly, a current collecting plate welded to an uncoated portion of the electrode assembly is again fixed to pass through a closed surface provided at one end of a cylindrical battery can accommodating the electrode assembly. It relates to a welding inspection device and a welding inspection method capable of inspecting the welding state after the electrode terminal and the electrode assembly are welded from the inside of the hollow part. The battery can is fixed by a jig, and the welding inspection device is a vision camera inspection device having an endoscope or a telephoto lens, and the welding portion is inserted through an opening provided at the other end of the battery can or not inserted. And it is possible to inspect the defect due to weak welding, over-welding, or welding spatter by photographing the inner surface of the hollow part. Also, this can be applied to specimens on a linear track.

Description

Welding inspection device {WELDING INSPECTION APPARATUS}

The present invention relates to a welding inspection device, and more particularly, to a device for inspecting a welding condition inside a hollow portion of a cylindrical electrode assembly on a linear track.

Secondary batteries, which are easy to apply according to product groups and have electrical characteristics such as high energy density, are common not only in portable devices but also in electric vehicles (EVs) or hybrid electric vehicles (HEVs) driven by an electrical driving source. is being applied to

These secondary batteries have not only the primary advantage of significantly reducing the use of fossil fuels, but also the advantage of not generating any by-products due to the use of energy, so they are attracting attention as a new energy source for improving eco-friendliness and energy efficiency.

Currently, types of secondary batteries widely used include lithium ion batteries, lithium polymer batteries, nickel cadmium batteries, nickel hydride batteries, nickel zinc batteries, and the like. The operating voltage of such a unit secondary battery cell, that is, a unit battery cell is about 2.5V to 4.5V. Therefore, when an output voltage higher than this is required, a battery pack may be configured by connecting a plurality of battery cells in series. In addition, a battery pack may be configured by connecting a plurality of battery cells in parallel according to the charge/discharge capacity required of the battery pack. Accordingly, the number of battery cells included in the battery pack and the type of electrical connection may be variously set according to a required output voltage and/or charge/discharge capacity.

Meanwhile, as types of unit secondary battery cells, cylindrical, prismatic, and pouch-type battery cells are known. In the case of a cylindrical battery cell, a separator, which is an insulator, is interposed between a positive electrode and a negative electrode, and the electrode assembly in the form of a jelly roll is formed by winding the separator, and the electrode assembly is inserted into the battery can to configure the battery. An electrode tab in the form of a strip may be connected to the non-coated portion of each of the positive and negative electrodes, and the electrode tab electrically connects the electrode assembly and an electrode terminal exposed to the outside. For reference, the positive electrode terminal is a cap plate of a sealing body sealing the opening of the battery can, and the negative electrode terminal is the battery can. However, according to the conventional cylindrical battery cell having such a structure, since current is concentrated on the strip-shaped electrode tab coupled to the positive electrode uncoated portion and/or the negative electrode uncoated portion, resistance is high, a lot of heat is generated, and the current collection efficiency is poor. There was a problem that it wasn't.

Resistance and heat generation are not a big issue for small cylindrical battery cells with 18650 or 21700 form factors. However, when the form factor of the cylindrical battery cell is increased to apply it to an electric vehicle, a problem in that a large amount of heat is generated around the electrode tab during rapid charging may cause the cylindrical battery cell to ignite.

In order to solve this problem, a cylindrical battery having a structure in which the positive and negative uncoated regions are located at the top and bottom of the jelly roll type electrode assembly, and a current collecting plate is welded to the uncoated region to improve the current collection efficiency. A cell (a so-called tab-less cylindrical battery cell) is presented.

In a tabless cylindrical battery cell, a current collector plate is welded to an uncoated portion of an electrode assembly, and the current collector plate is fixed to pass through one end of the battery can and welded from the inside of the battery can to an electrode terminal protruding out of the battery can. There may be one configured so that the electrode assembly can be electrically connected to the outside.

1 is a state in which an uncoated portion of an electrode assembly and a first current collecting plate are welded to each other during a manufacturing step of a cylindrical battery cell, and then a first electrode terminal riveted to one end of a battery can and the first current collecting plate are welded. is a side cross-sectional view of Referring to this, the first current collector plate 13 is welded to the first non-coated portion 111a, and the electrode assembly 11 has a second non-coated portion 111b inside the battery can 12. It is accommodated facing the opening 121 of the. The first current collector plate 13 is welded to the first electrode terminal 15 rivet-fixed to pass through the bottom surface of the battery can 12 and the welding portion 13W located at one end of the hollow part 11H. .

In the case of the cylindrical battery cell having the above structure, since the welding part 13W is difficult to check without passing through the hollow part 11H, it is difficult to inspect the welding state through a general vision camera inspection device. There are difficulties.

The present invention was invented under the background of the prior art as described above, and a current collector plate welded to one uncoated portion of a jelly roll type electrode assembly accommodated in a cylindrical battery can having a closed surface at one end and an open portion at the other end, It is an object of the present invention to provide a welding inspection device and inspection method capable of inspecting welding conditions such as over-welding or weak welding between electrode terminals fixed to penetrate the closure surface.

Another technical problem of the present invention, when the welding inspection device is a vision camera, by appropriately presenting the lens angle of view of the vision camera to weld spatter on the inner circumferential surface of the hollow part along with welding conditions such as over-welding of the welded part It is an object of the present invention to provide an inspection device capable of inspecting defects due to

Another technical problem of the present invention is to provide a welding inspection method for applying the welding inspection device to a specimen on a linear track.

Another technical problem of the present invention is to improve the economics of the entire manufacturing process through optimization of the processing process of the welding inspection method for the sample on the linear track.

The technical problems of the present invention are not limited to the above-mentioned purposes, and other objects and advantages of the present invention not mentioned above can be understood by the following description and will be more clearly understood by the embodiments of the present invention. . It will also be readily apparent that the objects and advantages of the present invention may be realized by means of the instrumentalities and combinations indicated in the claims.

In order to solve the above problems, the present invention provides a jig for supporting and fixing a battery can, which is a sample, with its opening facing in a first direction, and a welded portion between a first current collecting plate and a first electrode terminal and a lens aligned in the first direction. And it provides a welding inspection device including a camera equipped with an image detection sensor.

The electrode assembly accommodated in the battery can may have a first uncoated portion and a first current collecting plate welded thereto at one end in the axial direction thereof, and a second uncoated portion and a second current collecting plate welded thereto at the other end thereof. In addition, a central hole equal to or larger than the inner diameter of the other end of the hollow part may be provided in the second current collecting plate so that the hollow part of the electrode assembly can be opened through the opening of the battery can.

The camera may include an endoscope at one end thereof moved and inserted into the hollow part along a first direction to take a close-up picture of the welding part.

An outer diameter of the endoscope unit may be smaller than an inner diameter of the hollow part.

The endoscope unit may pass through a central hole of the second current collecting plate and be inserted into the hollow part.

The endoscope unit may have a lens and a light at an end thereof in the first direction, and the light may be integral with the lens.

The endoscope unit may be inserted into the hollow part by approaching the camera along the first direction to the specimen, or the jig may be inserted into the hollow part by approaching the specimen itself to the camera in the first direction.

The endoscope unit may include a submotor capable of parallel movement in an X-axis, a Y-axis, or a Z-axis in order to align or focus with the welded portion or hollow portion before and after the insertion. The submotor may be provided in a number of cases ranging from enabling movement in any one of the three directions to enabling free movement in all three directions.

The lens may be a wide-angle lens. The wide-angle lens may mean having an angle of view wide enough to photograph an inner circumferential surface of the hollow part in a state in which the endoscope is inserted into the hollow part.

The lens may be a telephoto lens. The telephoto lens may mean having a focal length long enough to photograph the welded portion without being inserted into the hollow part, such as the camera not having an endoscope.

The camera may be connected to an external image processing device to derive inspection results by processing images acquired by the image detection sensor.

The image processing device may be programmed to output an inspection decision signal by processing an image of the welded portion acquired by the image sensor to determine whether the welded portion is weakly welded, normal welded, or excessively welded. .

The image processing device identifies whether a pupil is generated due to over-welding in the welded region from the image of the welded region obtained by the image sensor, thereby determining whether the welded region is over-welded and outputting an inspection decision signal. It may have been programmed to do so.

The image processing device may be programmed to process an image of an inner circumferential surface of the hollow part acquired by the image sensor, determine whether spatter due to welding has occurred on the inner circumferential surface, and output an inspection determination signal.

The present invention also provides a method of inspecting a welding state by photographing the welding portion or the inner circumferential surface of the hollow portion using the welding inspection device.

The welding inspection method may be an inspection method for determining whether the welding portion is weakly welded, normal welded, or excessively welded.

The welding inspection method may be an inspection method for determining whether welding spatter is generated on an inner circumferential surface of the hollow part. Alternatively, the welding inspection method may be an inspection method for determining whether the welding spatter has occurred and whether the welding portion has weak welding, normal welding, or excessive welding.

The welding inspection method may target a sample on a linear track.

The weld inspection method on the linear track can be configured to provide a trigger input only when product data is present.

The welding inspection method on the linear track may be set to an inspection machine pass mode in which the trigger is always in an ON state and the inspection decision signal is ignored.

The welding inspection method on the linear track may be set to have a defect rate of 200PPM. Based on the defect rate, the tact time of the linear track may be set to 300 ms or less.

The tack time may be set to 200 ms or less in consideration of the scan time.

The present invention includes a camera having an endoscope unit provided with lighting and a lens, and the endoscope unit is inserted into the hollow of a jelly roll type electrode assembly accommodated in a cylindrical battery can having a closed surface at one end and an open part at the other end. Accordingly, it is possible to provide a welding inspection device capable of inspecting a welding state between an uncoated portion of one side of the electrode assembly, a welded current collecting plate, and an electrode terminal fixed to pass through the closed surface.

In another aspect of the present invention, it is possible to provide a welding inspection device in which the endoscope can freely move in parallel.

In another aspect, the present invention can provide a welding inspection device capable of inspecting the welding state of the welding portion by including a telephoto lens even though the camera does not include an endoscope or is not inserted into the hollow portion.

In another aspect of the present invention, it is possible to provide a welding inspection device capable of inspecting whether welding spatter is generated by photographing the inner circumferential surface of the hollow part of the electrode assembly.

In another aspect of the present invention, it is possible to provide a welding inspection method targeting a sample on a linear track using the welding inspection device.

In another aspect, the present invention may provide a welding inspection method for conducting a welding inspection on the linear track with a tack time of 200 ms or less.

In addition, the present invention may have various other effects, which will be described in each embodiment, or descriptions of effects that can be easily inferred by those skilled in the art will be omitted.

1 is a cross-sectional view of a cylindrical battery cell in the manufacturing process in which a first electrode uncoated portion of a jelly roll type electrode assembly is welded to a first current collector plate, and the first collector plate is welded to a first electrode terminal.
2 is a schematic diagram showing a camera having an endoscope inserted into a hollow part of an electrode assembly to inspect a welding state between a first current collecting plate and a first electrode terminal.
3 is a schematic diagram showing a state in which a camera having an endoscope is inserted into a hollow part of an electrode assembly.
4 is a schematic view showing a state in which a camera having an endoscope and a wide-angle lens is inserted into a hollow part of an electrode assembly and photographs an inner circumferential surface of the hollow part.
5 is a schematic view showing a state in which a camera having a telephoto lens is not inserted into an electrode assembly and photographs a welding portion.
6 is a flowchart illustrating a method of inspecting a welding state using a welding inspection device having an endoscope on a linear track in a time-sequential manner.

The above objects, features and advantages will be described later in detail with reference to the accompanying drawings, and accordingly, those skilled in the art to which the present invention belongs will be able to easily implement the technical spirit of the present invention. In describing the present invention, if it is determined that the detailed description of the known technology related to the present invention may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted. Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to indicate the same or similar components.

Although first, second, etc. are used to describe various components, these components are not limited by these terms, of course. These terms are only used to distinguish one component from another component, and unless otherwise stated, the first component may be the second component, of course.

Throughout the specification, unless otherwise stated, each element may be singular or plural.

Hereinafter, the arrangement of an arbitrary element on the "upper (or lower)" or "upper (or lower)" of a component means that an arbitrary element is placed in contact with the upper (or lower) surface of the component. In addition, it may mean that other components may be interposed between the component and any component disposed on (or under) the component.

In addition, when a component is described as "connected", "coupled" or "connected" to another component, the components may be directly connected or connected to each other, but other components may be "interposed" between each component. ", or each component may be "connected", "coupled" or "connected" through other components.

Singular expressions used herein include plural expressions unless the context clearly dictates otherwise. In this application, terms such as "consisting of" or "comprising" should not be construed as necessarily including all of the various components or steps described in the specification, and some of the components or some of the steps It should be construed that it may not be included, or may further include additional components or steps.

Also, singular expressions used in this specification include plural expressions unless the context clearly indicates otherwise. In this application, terms such as "consisting of" or "comprising" should not be construed as necessarily including all of the various components or steps described in the specification, and some of the components or some of the steps It should be construed that it may not be included, or may further include additional components or steps.

Throughout the specification, when it says "A and/or B", it means A, B or A and B, unless otherwise specified, and when it says "C to D", it means no particular contrary description As long as there is no, it means C or more and D or less.

For convenience of explanation, in this specification, a direction (Y) along the longitudinal direction of the winding shaft of the electrode assembly wound in the form of a jelly roll is referred to as an axial direction or a width direction. And, the direction X surrounding the winding shaft is referred to as a circumferential direction or a circumferential direction. Further, a direction Z that is closer to or away from the winding axis is referred to as a radial direction or a radial direction. Among these, a direction closer to the winding axis is referred to as a centripetal direction, and a direction away from the winding axis is referred to as a centrifugal direction.

In the present invention, a cylindrical battery cell including a jelly roll-type electrode assembly 11 in which a positive electrode plate, a negative electrode plate, and a separator interposed therebetween are stacked and wound while surrounding a winding center, particularly a tabless cylindrical battery cell A welding inspection device and a welding inspection method used in the manufacturing process are provided. Such an inspection device and welding inspection method not only in the process of manufacturing the tabless cylindrical battery cell, but also inspects the welding state of any specimen that includes a narrow and long hollow part and has a welded part at one end inside the hollow part, as will be described later. Of course, it can be sufficiently applied and applied by a person skilled in the art.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

1 is a cross-sectional view of a cylindrical battery cell during manufacturing. Referring to this, the cylindrical battery cell is provided on the jelly roll type electrode assembly 11 and the first electrode uncoated portion 111 and the second electrode uncoated portion 111 provided at both ends in the axial direction of the electrode assembly 11. Each of the welded first and second collector plates 13 and 14 has a cylindrical battery can having a closed surface 122 at one end in the axial direction and an opening 121 at the other end ( 12), the first electrode terminal 15 is provided at the central portion of the closed surface 122 and is fixed while penetrating the closed surface 122. The first current collecting plate 13 is welded to the first electrode terminal 15 from the inside through the hollow part 11H extending through the central axis 11A of the electrode assembly 11, and the welding portion 13W ) to form

Welding between the first current collecting plate 13 and the first electrode terminal 15 is performed by a separator and a core (a tubular member positioned at the winding center in a jelly roll type electrode assembly) that may be disposed on the inner surface of the hollow part 11H. ), it can be made by inserting a welding rod and a guide in order not to damage it. However, the welding method is not necessarily limited thereto, and various welding methods such as laser welding and resistance welding can be applied.

The second current collecting plate 14 has a central hole 14H whose inner diameter is equal to or larger than the inner diameter of the opening of the other axial end of the hollow part 11H, so that the second current collecting plate 14 is Even after being welded, the hollow part 11H may be formed to be open toward the other side in the axial direction. As will be described later, by providing such a center hole 14H, it is possible to inspect the welding state between the first current collecting plate 13 and the first electrode terminal 15 even when the second current collecting plate 14 is welded. it becomes possible

The first electrode terminal 15 may be insulated from the battery can 12 with a gasket or the like. In addition, the second current collecting plate 14 may be electrically connected to the battery can 12 later, and in this case, the first electrode terminal 15 connects the negative electrode or positive electrode of the electrode assembly 11 to the outside. It is a terminal enabling connection, and the battery can 12 may be a terminal enabling the positive electrode or negative electrode of the electrode assembly 11 to be connected to the outside.

The sample of the welding inspection device or welding inspection method according to the present invention is assembled and welded to include the battery can 12, the electrode assembly 11, the first current collector plate 13, and the first electrode terminal 15. may be in a completed state. In addition, when the second current collector plate 14 has a center hole 14H, the other end of the hollow portion 11H in the axial direction is open even when welding to the second current collector plate 14 is completed. Therefore, it is possible to perform the welding inspection in a state in which welding to the second current collecting plate 14 is completed, since optical access to the welding portion 13W, that is, shooting is possible.

2 is a schematic diagram showing that an endoscope 424 is provided as a camera 42 included in a welding inspection device according to another embodiment of the present invention and photographs a welding region 13W. Referring to this, the camera 42 essentially includes a lens 422 and an image detection sensor 421, and may additionally include an endoscope 424 and/or a light 423.

The image detection sensor 421 is a sensor that acquires an image through light coming from the lens 422, and the image acquired by the image detection sensor 421 is transferred to an image processing device connected to the outside of the camera 42. can be transmitted The image processing device may be programmed to analyze an image acquired by the image detection sensor 421 to determine a welding state of the welding portion 13W.

The welding state may mean weak welding, normal welding, or over-welding. In the image processing device, when the camera 42 can capture even the inner circumferential surface of the hollow part 11H of the electrode assembly 11, the image of the inner circumferential surface of the hollow part 11H acquired by the image sensor 421 It may be possible to determine whether or not welding spatter occurs on the inner circumferential surface of the hollow part 11H by analyzing.

As will be described later, the endoscope unit 424 may be moved and inserted into the hollow part 11H of the electrode assembly 11 to photograph the welded part 13W.

The illumination 423 may be disposed adjacent to the lens 422 so as to be irradiated to a photographing portion of the lens 422, and may be integrated with the lens 422 as shown in FIG. 2 . The lighting 423 may be disposed in an appropriate location and in an appropriate direction so as to illuminate the welding portion 13W by irradiating into the hollow portion 11H. When the camera includes the endoscope part 424 , the lighting 423 may be located at a distal end of the endoscope part 424 .

3 is a schematic diagram showing a state in which a camera 42 having an endoscope unit 424 according to an embodiment of the present invention is inserted into the hollow part 11H of the electrode assembly 11. Referring to this, in one embodiment of the present invention, the jig 41 fixes the battery can 12 so that the opening 121 faces the first direction, and the camera (with the endoscope 424) 42), the lens 422 located at the distal end of the endoscope unit 424 and the image detection sensor 421 located on the body side of the camera 42 are aligned in the first direction from the welding portion 13W. It is disposed on the side of the open part 121 of the battery can 12 in the state.

The endoscope part 424 extends along the central axis 11A of the electrode assembly 11 to bring the lens 422 close to the welding part 13W and can be inserted into the hollow part 11H. As the endoscope part 424 is inserted into the hollow part 11H, the camera 42 may photograph the welding portion 13W through the lens 422 provided at the distal end of the endoscope part 424.

The endoscope part 424 may have an outer diameter smaller than an inner diameter of the hollow part 11H for the insertion. The endoscope part 424 may also pass through the central hole 14H provided in the second current collector plate 14 and be inserted into the hollow part 11H. To this end, the endoscope part 424 has an outer diameter This may be smaller than the inner diameter of the second current collecting plate 14 .

The method of moving the endoscope part 424 to be inserted into the hollow part 11H may vary. For example, the camera 42 as a whole may approach and move toward the welding portion 13W. Alternatively, in a state in which the camera 42 is fixed, only the endoscope part 424 may be independently extended to approach the welding portion 13W. Alternatively, the endoscope part 424 may be inserted into the hollow part 11H by the jig 41 moving the battery can itself along the first direction.

In this case, the distal end of the endoscope part 424 may include a light 423, and the light 423 may be integrated with the lens 422.

The endoscope unit 424 may be equipped with a servomotor so that it can freely move in parallel along the X-axis, Y-axis, and/or Z-axis before and after being inserted into the hollow part 11H or while being inserted. The sub-motor may be used to fine-tune the shooting area or focus of the camera 42 .

The image acquired by the image sensor 421 through the lens 422 is transmitted to the image processing device, and the welding state of the welding portion 13W, that is, weak welding, normal welding, or over-welding is determined. . The image processing device may be programmed to determine the welding state by analyzing an image acquired and transmitted by the image detection sensor 421 . For example, the image processing device may be programmed to determine the over-welding by identifying whether a pupil due to the over-welding appears in the image of the welding portion 13W obtained and transmitted by the image sensor 421. can That is, it may be a kind of vision inspection device.

FIG. 4 is a schematic diagram illustrating a state in which a camera additionally equipped with a wide-angle lens is inserted into the hollow part of the electrode assembly in FIG. 3 and photographs the inner circumferential surface of the hollow part. Referring to this, in one embodiment of the present invention, the lens 422 provided at the distal end of the endoscope unit 424 may be a wide-angle lens. The wide-angle lens may refer to a lens 422 having a sufficiently wide angle of view 422A so that the camera 42 may photograph the inner circumferential surface of the hollow part 11H.

An image obtained by the image sensor 421 through the lens 422 is transmitted to an image processing device, and it is determined whether or not welding spatter is generated on the inner circumferential surface of the hollow part 11H. The image processing device may be programmed to analyze an image acquired and transmitted by the image detection sensor 421 to determine whether or not the welding spatter has occurred. For example, the image processing device identifies whether a spatter shape due to welding appears in the image of the inner circumferential surface of the hollow part 11H obtained and transmitted to the image detection sensor 421 to determine whether the welding spatter has occurred can be programmed to do so.

The inspection of the welding state and the inspection of whether or not the welding spatter occurs may be simultaneously performed by one welding inspection device including an endoscope unit 424 having a wide-angle lens 422 at its distal end. In this case, the image processing device may be programmed to simultaneously determine the welding state and whether welding spatter has occurred.

5 is a schematic diagram showing a state in which a camera having a telephoto lens according to another embodiment of the present invention photographs a welding portion without being inserted into an electrode assembly. Referring to this, in one embodiment of the present invention, the jig 41 fixes the battery can 12 so that the open portion 121 faces the first direction, and the camera 42 fixes the battery can 12 to the welding portion 13W. Based on ), the lens 422 and the image detection sensor 421 may be arranged to be aligned in the first direction. In this case, the camera 42 may not include the endoscope part 424 and the lens 422 may not be inserted into the hollow part 11H.

In this case, the lens 422 may be a telephoto lens. The telephoto lens may mean a lens having a narrow angle of view 422A and a long focal length so that the welded portion 13W can be photographed without the lens 422 being inserted into the hollow part 11H. there is. The camera 42 may include a light 423 adjacent to the lens 422 , and the light 423 may be integral with the lens 422 .

The image acquired by the image sensor 421 through the lens 422 is transmitted to the image processing device, and the welding state of the welding portion 13W, that is, weak welding, normal welding, or over-welding is determined. . The image processing device may be programmed to determine the welding state by analyzing an image acquired and transmitted by the image detection sensor 421 . For example, the image processing device may be programmed to determine the over-welding by identifying whether a pupil due to the over-welding appears in the image of the welding portion 13W obtained and transmitted by the image sensor 421. can

The welding inspection device may target a sample on a linear track. The linear track may be a linear track on which the tabless cylindrical battery cell is manufactured. On the linear track, the specimen first undergoes a welding process through a welding device before moving to the welding inspection device. The welding process refers to welding between the first collecting plate 13 and the first electrode terminal 15, welding between the first collecting plate 13 and the first uncoated portion 111a, and/or the first non-coated portion 111a. It may be a welding process between the second current collecting plate 14 and the second uncoated portion 111b.

6 is a flowchart illustrating a method of inspecting a welding state of a specimen on a linear track using a welding inspection apparatus including an endoscope unit 424 according to an embodiment of the present invention in a time-sequential manner. Hereinafter, the welding inspection method will be described with reference to FIGS. 3 to 6 .

The battery can 12 that has completed the welding process moves to the welding inspection position on the linear track together with the jig 41 (S11). At the welding inspection position, the battery can 12 has its opening 121 facing the first direction by the jig 41, and the lens 422 included in the camera 42 of the welding inspection device. and the image detection sensor may be fixed so as to be aligned in the first direction along the central axis 11A of the electrode assembly 11 from the welding portion 13W between the first current collecting plate 13 and the first electrode terminal 15. there is.

The endoscope part 424 is inserted into the hollow part 11H of the electrode assembly 11 (S12). The endoscope part 424 may extend from the main body of the camera 42 into the hollow part 11H along the central axis 11A of the electrode assembly 11 . At this time, the insertion may be performed by moving the welding inspection device or the entire camera 42 in the direction of the welding site, and only the endoscope 424 extends independently so as to insert the lens 422 into the welding site. 13W, or by moving the jig 41 to bring the battery can 12 close to the lens 422. The lens 422 may be provided at a distal end of the endoscope unit 424, and the illumination 423 may be provided at a portion adjacent to the lens 422 or integrally with the lens 422. The above process (S12) may be omitted in the welding inspection method using the welding inspection device having the telephoto lens.

The camera 42 captures the welding portion 13W and transmits the image to the image processing device (S13). The photographing may be performed by acquiring an image of the welding portion 13W to the image sensor 421 through the lens 422 . In the above process, in the welding inspection method using the welding inspection device having the wide-angle lens, the inner circumferential surface of the hollow portion 11H may be simultaneously photographed in order to inspect whether or not welding spatter occurs as well as the welding portion 13W. can

The image processing device analyzes the image and determines whether it is defective (S13). The image processing device may be programmed to analyze an image acquired and transmitted from the image detection sensor 421 to determine welding defects. That is, the image processing device may be programmed to analyze the image of the welded portion 13W to determine whether there is weak welding, normal welding, or excessive welding. For example, the image processing device may be programmed to determine whether there is over-welding by identifying whether or not a pupil appears due to over-welding in the image of the welding region 13W. In the above process, in the welding inspection method using the welding inspection device having the wide-angle lens, it is possible to simultaneously determine whether welding spatter is generated on the inner circumferential surface of the hollow part 11H as well as the welding state of the welding region 13W. It can be programmed to

The welding inspection method on the linear track can be set to provide a trigger input only when there is product data, or can be set to an inspector pass mode in which the trigger is always in an ON state and the inspection decision signal is ignored.

The welding inspection method on the linear track may be set to have a defect rate of 200PPM. Based on the defect rate, the tact time of the linear track may be set to 300 ms or less. The tack time may be set to 200 ms or less in consideration of the scan time.

It should be understood that the foregoing embodiments are illustrative in all respects and not restrictive, and the scope of the present invention will be indicated by the following claims rather than the foregoing detailed description. And it should be construed that all changes and modifications derived from the meaning and scope of the claims to be described later, as well as equivalent concepts, are included in the scope of the present invention.

As described above, the present invention has been described with reference to the drawings illustrated, but the present invention is not limited by the embodiments and drawings disclosed herein, and various modifications are made by those skilled in the art within the scope of the technical idea of the present invention. It is obvious that variations can be made. In addition, although the operation and effect according to the configuration of the present invention have not been explicitly described and described while describing the embodiments of the present invention above, it is natural that the effects predictable by the corresponding configuration should also be recognized.

1: battery cell (cylindrical battery cell)
11: electrode assembly
11A: central axis
11H: hollow part
111: unregistered
111a: first no branch
111b: second no branch
12: battery can
121: opening
122 closed surface
13: first collector plate
13W: welding area
14: second collector plate
14H: central hall
15: first electrode terminal
2: linear track
3: welding device
4: welding inspection device
41: jig
42: camera
421: image detection sensor
422: lens
422A: angle of view
423: lighting
424: endoscope unit
P: battery pack
V: car

Claims (14)

An inspection device for inspecting a welded portion of a first electrode terminal fixed to a closed surface of a battery can and a first current collector plate of a jelly-roll type electrode assembly accommodated in the battery can,
a jig supporting the battery can so that the open portion of the battery can faces a first direction; and
Including; a camera disposed facing the opening,
The camera is:
An image detection sensor for obtaining an image; and
A lens disposed between the image detection sensor and the welding portion so that the image is focused on the image detection sensor;
The jig supports the electrode assembly so that the central axis of the electrode assembly is parallel to the first direction,
The image detection sensor and the lens are aligned in a first direction with the hollow part of the electrode assembly extending along the central axis of the electrode assembly.
The method of claim 1,
The camera includes an endoscope having an outer diameter smaller than an inner diameter of the hollow part so as to move and insert into the hollow part along a first direction and approach the welding part;
Wherein the endoscope unit is provided with the lens and lighting at an end in a first direction, a welding inspection device.
The method of claim 2,
The illumination is integral with the lens, the welding inspection device.
The welding inspection apparatus according to claim 2, wherein a sub-motor is mounted so that the endoscope can freely move in parallel along the X-axis, Y-axis, and Z-axis.
The method of claim 1,
The lens has a long focal length so that the welding portion can be photographed without being inserted into the hollow portion, the welding inspection device.
According to any one of claims 2 to 4,
The lens has a wide angle of view to check the welding spatter on the inner circumferential surface of the hollow portion, the welding inspection device.
The method according to any one of claims 1 to 5,
The welding inspection method of analyzing the image of the welding portion obtained by the image sensor to inspect whether there is a welding defect.
The method of claim 7,
The welding inspection method is a welding inspection method for a sample on a linear track.
The method of claim 8,
The welding inspection method is processed in a time of 300 ms or less, welding inspection method.
The method of claim 8,
The welding inspection method is processed in a time of 200 ms or less, welding inspection method.
The method of claim 6,
The welding inspection method of analyzing the image of the inner circumferential surface of the hollow part obtained by the image sensor to inspect whether there is a defect due to welding spatter.
The method of claim 11,
The welding inspection method is a welding inspection method for a sample on a linear track.
The method of claim 12,
The welding inspection method is processed in a time of 300 ms or less, welding inspection method.
The method of claim 12,
The welding inspection method is processed in a time of 200 ms or less, welding inspection method.

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