Electrode Sheet Alignment Mechanism and X-ray Inspection Device for Cylindrical Secondary Batteries Having the Same

Abstract

An X-ray inspection device for a cylindrical secondary battery includes: an inspection chamber; a transfer unit for transferring the cylindrical secondary battery into the inspection chamber; an inspection unit that moves while holding the secondary battery; an X-ray source; an X-ray detector; a release unit for releasing the inspected secondary battery to the outside of the inspection chamber; and an alignment mechanism that is arranged along the movement path of the inspection unit to align the cylindrical secondary battery. Moreover, in the X-ray inspection device for a cylindrical secondary battery of the present invention, the alignment mechanism includes: one or more sensing units for sensing the position of a specific part of the cylindrical secondary battery; and one or more contact units that can operate between a standby position where they do not contact the secondary battery and a contact position where they can contact the secondary battery.

Description

Technical Field

[0001] The present invention relates to a secondary battery, and more particularly, to an X-ray inspection apparatus and method for inspecting whether a cylindrical secondary battery is defective. Background Art

[0002] X-ray inspection is applied to various industrial fields, and various types of inspection apparatuses are known according to the product types in each application field. For example, an X-ray inspection apparatus can be used for defect inspection of printed circuit boards, defect inspection of electronic devices, defect inspection of food containers, or sensing of foreign substances in food.

[0003] Generally, an object to be inspected in an X-ray inspection apparatus can be continuously supplied by a transfer unit such as a transfer conveyor. In addition, an X-ray source and a detector form an X-ray projection image in a shielded inspection chamber, and it can be determined whether there is a defect in the product based on the obtained image. During this inspection process, it is necessary to shield X-rays and align the object to be inspected in an appropriate form.

[0004] An X-ray inspection apparatus for a cylindrical secondary battery determines whether there is a defect by X-ray fluoroscopy to check the serpentine state of the "+" electrode and the "-" electrode that may occur in the winding process of generating the characteristics of the cylindrical battery product, the alignment state of the "+" electrode and the "-" electrode inside the battery, the electrode gap, etc.

[0005] Generally, an X-ray inspection apparatus for a secondary battery is configured to be provided with an inspection chamber that forms a space for shielding X-rays, and the secondary battery is placed inside the inspection chamber and transferred to an inspection position. X-rays are irradiated onto the secondary battery from the inspection position, and after an image projected through the secondary battery is captured using an X-ray detector, it is determined whether the secondary battery is defective based on the image information output from the X-ray detector.

[0006] Figure 1 FIG. is a top view briefly showing a conventional X-ray inspection apparatus for inspecting whether a cylindrical lithium-ion secondary battery is defective. Among them, the secondary battery 10 is moved to the support groove 22a of the inspection support cylinder 22 by the first transfer conveyor 12, and is moved to the first inspection position provided with the first X-ray source 24 and the first X-ray detector 26 by the rotation of the inspection support cylinder 22. At the first inspection position, the first X-ray source 24 and the first X-ray detector 26 are correspondingly arranged corresponding to the upper part of the secondary battery so as to be able to inspect, for example, the electrode gap at the upper part of the secondary battery. An inspector determines whether the electrode gap of the secondary battery is defective based on the upper image of the secondary battery sent to an external monitor. If it is determined to be defective, a removal command for separating the corresponding secondary battery to the side of the transfer conveyor 32 through the defective product diaphragm 30 is input to the controller.

[0007] The secondary battery passing through the first inspection position is again moved to the second inspection position provided with the second X-ray source 34 and the second X-ray detector 36 by the rotational movement of the inspection support cylinder, thereby inspecting the lower part of the secondary battery.

[0008] As a related prior art, the "Battery Automatic Continuous Inspection Device" of Korean Patent No. 10-1272556 (authorized on June 3, 2013) is disclosed. This device relates to the inspection of prismatic batteries and includes: a disk-shaped supply lifting and rotating part, an inspection rotating part provided with a rotating circular disk, and a disk-shaped discharge lifting and rotating part. The supply lifting and rotating part, the inspection rotating part, and the discharge lifting and rotating part are connected and configured to rotate simultaneously by one driving unit.

[0009] As another prior art, the "X-ray Inspection Device for Battery Inspection and Its Battery Inspection Method" of Korean Patent No. 10-1707220 (authorized on February 9, 2017) is disclosed. The feature of this prior art is that it includes a guiding unit for guiding an object to be inspected to different rotating units forming a rotating table structure. The rotating table structure has fitting fixing blocks that can be continuously fitted with each other, so that each object to be inspected is fixed and transferred. The part of the fitting fixing block that contacts the lower surface of the object to be inspected is curved.

[0010] As described above, in the prior art, it has not been recognized that the accuracy of the X-ray projection image may depend on the position of the electrode tab of the cylindrical secondary battery. Therefore, a method or device for improving the accuracy of defect inspection by controlling the position of the electrode tab has not been proposed. Summary of the Invention

[0011] Technical Problem

[0012] A cylindrical secondary battery generally includes: an electrode assembly formed by winding a positive electrode plate, a negative electrode plate, and a separator. The positive electrode active material is coated on the positive electrode plate, the negative electrode active material is coated on the negative electrode plate, and the separator is located between the positive electrode plate and the negative electrode plate; a secondary battery case for accommodating the electrode assembly; and an electrolytic solution injected inside the secondary battery case to allow lithium ions to move.

[0013] Refer to Figure 2a , after laminating the positive electrode plate 110 coated with the positive electrode active material and connected to the positive electrode tab 111, the negative electrode plate 120 coated with the negative electrode active material and connected to the negative electrode tab 121, and the separator 130, they are wound around the reel 140 to prepare the electrode assembly 90. As Figure 2cAs shown, the cylindrical secondary battery 100 is prepared by installing the electrode assembly 90 into the upper insulating plate 142, the lower insulating plate 143, and the cylindrical can 144. During this process, the reel 140 is separated and can be inserted into the core unit 141. In the manufacturing process, the above-mentioned positive electrode plate 111 and negative electrode plate 121 are connected to the corresponding positions above and below the electrode assembly (refer to Figure 2b ), or at least connected to the same side of the electrode assembly (refer to Figure 2c ).

[0014] The accuracy of defect inspection may vary depending on the direction of the X-ray irradiated onto the cylindrical battery. For example, when the X-ray irradiates the joint part of the electrode plates of the cylindrical battery, the X-ray image may be distorted due to the interference of the electrode plates.

[0015] Figure 3a FIG. is an example of an X-ray projection image irradiated onto the part of the negative electrode plate 121 (refer to Figure 2c 'A' part) located at the lower part of the battery among a plurality of electrode plates. It can be confirmed that some distorted images appear at the lower end of the image. This is an image distortion phenomenon caused by the interference of the negative electrode plate or the negative electrode plate welding part at the lower part of the battery. As shown in the figure, the electrode alignment 150, the separator gap 152, and the inter-pole gap 154 are distorted. If such a poor X-ray projection image is obtained, it is difficult to judge the defect. In this case, the corresponding object under inspection may need to be reinspected or classified as defective, which may result in a waste of time and money.

[0016] On the contrary, when the X-ray irradiates the part where the electrode plates are not connected, a good image without distortion can be obtained. Figure 3b FIG. is a projection image when the X-ray irradiates the Figure 2c dotted line part indicated by 'B' in FIG., and it can be confirmed that a clear image without distortion phenomenon is obtained.

[0017] As described above, when irradiating the X-ray while avoiding the joint parts of the positive electrode plate and the negative electrode plate, the interference during X-ray projection is minimized, and thus the accuracy of defect inspection is the highest.

[0018] Therefore, an object of the present invention is that even if the cylindrical secondary battery is placed in the X-ray inspection device in an arbitrary position or orientation, when it reaches the X-ray source, the X-ray can always be irradiated in a specified position or orientation.

[0019] Means for Solving the Problem

[0020] The X-ray inspection device for a cylindrical secondary battery of the present invention for achieving the above object includes the following aspects and any combination thereof.

[0021] One aspect of the present invention is an X-ray inspection device for a cylindrical secondary battery. The X-ray inspection device includes: an inspection chamber; a transfer unit for transferring the cylindrical secondary battery into the inspection chamber; an inspection unit that moves while holding the secondary battery; an X-ray source; an X-ray detector; and a release unit for releasing the inspected secondary battery to the outside of the inspection chamber. The X-ray inspection device for the cylindrical secondary battery includes an alignment mechanism arranged along the movement path of the inspection unit to align the cylindrical secondary battery.

[0022] Another embodiment of the present invention relates to an X-ray inspection device for a cylindrical secondary battery, wherein the inspection unit is a rotary inspection unit that rotates in a circle.

[0023] Another embodiment of the present invention relates to an X-ray inspection device for a cylindrical secondary battery, wherein the cylindrical secondary battery has an electrode tab protruding from the upper end, and the alignment mechanism aligns the electrode tab.

[0024] Still another embodiment of the present invention relates to an X-ray inspection device for a cylindrical secondary battery, wherein support grooves for the cylindrical secondary battery are provided at a predetermined interval around the inspection unit, and the secondary battery is held in the support grooves by adhesion.

[0025] Yet another embodiment of the present invention relates to an X-ray inspection device for a cylindrical secondary battery, wherein the alignment mechanism includes: one or more sensing units for sensing the position of a specific part of the cylindrical secondary battery; and one or more contact units that can operate between a standby position where they do not contact the secondary battery and a contact position where they can contact the secondary battery.

[0026] Yet another embodiment of the present invention relates to an X-ray inspection device for a cylindrical secondary battery. According to the sensing result of the sensing unit, it is determined whether the contact unit operates. When the secondary battery moves on the transfer unit, if the contact unit operates to the contact position, then as the secondary battery continues to move on the transfer unit, the secondary battery rotates by the contact friction force between the contact unit and the secondary battery.

[0027] Yet another embodiment of the present invention relates to an X-ray inspection device for a cylindrical secondary battery, wherein the contact unit includes a contact pad having a contact surface that contacts the cylindrical secondary battery.

[0028] Yet another embodiment of the present invention relates to an X-ray inspection device for a cylindrical secondary battery, wherein the rotation angle of the cylindrical secondary battery is determined according to the length of the contact surface.

[0029] Another embodiment of the present invention relates to an X-ray inspection apparatus for a cylindrical secondary battery, wherein the transfer unit intermittently performs pitching rotation in the order of rotation - stop - rotation, and when the transfer unit is in a stopped operation state during pitching rotation, the sensing unit senses the secondary battery.

[0030] Another embodiment of the present invention relates to an X-ray inspection apparatus for a cylindrical secondary battery, wherein the sensing unit and the contact unit are alternately arranged along the movement path of the inspection unit.

[0031] The alignment mechanism for a cylindrical object according to the present invention for achieving the above object includes the following aspects and any combination thereof.

[0032] One embodiment of the present invention relates to an alignment mechanism for a cylindrical object, which is used to align a cylindrical object (Cylindrical object) moved by being placed on a transfer unit to a desired position, and includes: a sensing unit for sensing the position of a specific part on the object; and a contact unit capable of operating between a standby position where it does not contact the object and a contact position where it can contact the object. The sensing unit and the contact unit are arranged along the movement path of the transfer unit, and it is determined whether the contact unit operates according to the sensing result of the sensing unit. When the object moves on the transfer unit, if the contact unit operates to the contact position, then as the object continues to move on the transfer unit, the object rotates by the contact friction force between the contact unit and the object.

[0033] Another embodiment of the present invention relates to an alignment mechanism for a cylindrical object, wherein the contact unit includes a contact pad having a contact surface that contacts the cylindrical object.

[0034] Another embodiment of the present invention relates to an alignment mechanism for a cylindrical object, and the rotation angle of the cylindrical object is determined according to the length of the contact surface.

[0035] Another embodiment of the present invention relates to an alignment mechanism for a cylindrical object, wherein the transfer unit intermittently performs pitching rotation in the order of movement - stop - movement.

[0036] The alignment method for a cylindrical object according to the present invention for achieving the above object includes the following aspects and any combination thereof.

[0037] One embodiment of the present invention relates to a method for aligning a moving cylindrical object. The cylindrical object moved by being placed on a transfer unit is aligned to a desired position by an alignment mechanism. The alignment mechanism includes: a sensing unit for sensing the position of a specific part on the cylindrical object; and a contact unit that can operate between a standby position where it does not contact the object and a contact position where it can contact the object. The method for aligning the moving cylindrical object includes the following steps: moving the cylindrical object using the transfer unit; sensing the position of a specific part of the cylindrical object using the sensing unit; determining whether the contact unit operates based on the position information of the specific part sensed by the sensing unit; when it is determined that the contact unit operates, the contact unit operates to the contact position; and the cylindrical object rotates by the contact friction force generated when it contacts the contact unit as it continues to move on the transfer unit.

[0038] Another embodiment of the present invention relates to a method for aligning a moving cylindrical object, where the cylindrical object is a secondary battery, and the specific part is an electrode tab protruding from the upper end of the secondary battery.

[0039] Another embodiment of the present invention relates to a method for aligning a moving cylindrical object, where the contact unit includes a contact pad having a contact surface that contacts the cylindrical object.

[0040] Still another embodiment of the present invention relates to a method for aligning a moving cylindrical object, where the rotation angle of the cylindrical object is determined according to the length of the contact surface.

[0041] Yet another embodiment of the present invention relates to a method for aligning a moving cylindrical object, where the transfer unit intermittently performs pitching rotation in the order of rotation - stop - rotation. When the transfer unit is in a stopped state during the pitching rotation, the sensing unit senses the secondary battery.

[0042] Effects of the Invention

[0043] The present invention will prevent inaccurate X - ray projection images from being obtained.

[0044] By reducing the possibility that the object to be inspected is re - examined or classified as defective, the accuracy and efficiency of X - ray inspection can be improved, thereby minimizing the waste of time and money. Brief Description of the Drawings

[0045] Figure 1 It is a top view of an X - ray inspection apparatus of the prior art.

[0046] Figure 2a Showing an electrode assembly of a cylindrical secondary battery Figure 2b is Figure 2a a side view of Figure 2c showing a secondary battery for inspection with one electrode tab protruding

[0047] Figure 3a and Figure 3b showing an X-ray projection image of a cylindrical secondary battery Figure 3a showing a defective X-ray projection image Figure 3b showing a good X-ray projection image

[0048] Figure 4a and Figure 4b showing embodiments of an X-ray inspection apparatus without an electrode tab alignment mechanism in a perspective view and a top view, respectively

[0049] Figure 5a is for showing Figure 4a and Figure 4b a perspective view of the state where an electrode tab alignment mechanism according to an embodiment of the present invention is installed in the apparatus Figure 5b is a view observed from Figure 5a the opposite direction

[0050] Figure 6 showing an embodiment of a sensing unit installed in an X-ray inspection apparatus according to the present invention

[0051] Figure 7 is a conceptual diagram showing a structure in which the above sensing unit senses a cylindrical secondary battery as an object to be inspected

[0052] Figure 8 showing an embodiment of a contact unit installed in an X-ray inspection apparatus according to the present invention

[0053] Figure 9a 、 Figure 9b 、 Figure 9c 、 Figure 9d and Figure 9e are conceptual diagrams showing a structure in which the above contact unit rotates a cylindrical secondary battery as an object to be inspected. As the rotation inspection unit rotates, Figure 9a showing a state where the contact unit extends to a contact position before the battery is aligned with the contact unit Figure 9b showing a state where the battery contacts the contact unit at an initial contact point Figure 9c showing a state where the battery rotates while in contact with the contact unit Figure 9d showing a state where the battery contacts the contact unit at a final contact point Figure 9e showing a state where the battery passes through the contact unit

[0054] Figure 10 Conceptual diagram for explaining the mechanism for sensing and rotating a plurality of secondary batteries placed in an X-ray inspection apparatus according to the present invention. Detailed implementation mode

[0055] The embodiments presented in the drawings are used to clearly understand the present invention, but the present invention is not limited thereto. In the following description, structural elements with the same reference numerals in different drawings have similar functions, so unless necessary for understanding the present invention, they will not be repeatedly described. Known structural elements will be briefly described or omitted, but this should not be construed as excluding them from the embodiments.

[0056] For clearly describing the present invention, the following terms are defined.

[0057] "Rotation": The movement of the object to be inspected located in the support groove of the rotation inspection unit 220 approaching or moving away from structural elements such as the X-ray source as the rotation inspection unit rotates. That is, it rotates with the center of the rotation inspection unit as the reference. Figure 7 , Figures 9a to 9e and Figure 10 are marked as "R" in

[0058] "Pitch rotation": The rotation inspection unit 220 rotates intermittently in the order of rotation action - stop action - rotation action.

[0059] "Rotation": The movement of the object to be inspected rotating within the support groove 222 of the rotation inspection unit 220. That is, the cylindrical object to be inspected 100 rotates with its own center as the reference. Figure 9c and Figure 10 are marked as "T" in

[0060] "Rotation distance": The circumferential distance that the cylindrical object to be inspected rotates.

[0061] "Rotation angle": The angle that the cylindrical object to be inspected rotates.

[0062] "Sensing alignment position": The position where the object to be inspected performing pitch rotation stops so that it can be sensed by the sensing unit.

[0063] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0064] Figure 4a and Figure 4b show an embodiment of the X-ray inspection apparatus 200 in a state where the electrode tab alignment mechanisms 250 and 270 are not provided.

[0065] The X-ray inspection apparatus 200 includes: a transfer conveyor 210 and a rotary feeder 212 for introducing the object to be inspected 100 into an inspection chamber (not shown); a rotary inspection unit 220 for transferring the object to be inspected to an inspection position; X-ray sources 230, 231 for irradiating X-rays onto the object to be inspected; X-ray detectors 235, 236 for detecting images projected when the X-rays pass through the object to be inspected; and a rotary exchanger 240 for discharging the object to be inspected after inspection.

[0066] Refer to Figure 4a and Figure 4b , the two X-ray sources 230, 231 can be arranged separately inside the rotary inspection unit 220, and the detectors 235, 236 for obtaining images from the projected X-rays caused by each X-ray source 230, 231 can be arranged outside the rotary inspection unit 220. The X-ray sources and the detectors can be arranged in opposite positions. Each X-ray source 230, 231 can irradiate X-rays at different heights of the battery. For example, as Figure 4a and Figure 4b shown, the first X-ray source 230 can irradiate X-rays at the lower part of the battery, and the second X-ray source 231 can irradiate X-rays at the upper part of the battery.

[0067] There is no particular limitation on the number of X-ray sources and detectors, which can be determined according to the specifications of the battery to be inspected. Also, the arrangement interval of different X-ray sources can be appropriately determined according to the arrangement space of the X-ray sources. The inspection results of the battery can be stored, and whether each battery is normal or defective can be stored. In addition, the battery that has completed the inspection can be discharged by the rotary exchanger 240.

[0068] Figure 5a and Figure 5b show that in Figure 4a and Figure 4b , the X-ray inspection apparatus is equipped with electrode tab alignment mechanisms 250, 270 according to an embodiment of the present invention, that is, a sensing unit 250 for sensing the object to be inspected and a contact unit 270 for rotating the object to be inspected. In Figure 5a and Figure 5b , in order to more clearly show the multiple objects to be inspected 100, the sensing unit 250, and the contact unit 270 introduced into the inspection apparatus, structures such as the transfer conveyor, the X-ray source, and the X-ray detector are omitted. Figure 5a and Figure 5b are views observed from opposite directions.

[0069] Refer to Figure 5a and Figure 5b, A plurality of cylindrical secondary batteries 100 as objects to be inspected are transferred to a rotary feeder 212 in a state of being placed in a support 214, and then housed in a support groove 222 of a rotary inspection unit 220. Among them, as in the case of normal X-ray inspection, in the cylindrical secondary battery 100 as the object to be inspected, in a state before an upper cover is inserted onto a jelly roll battery cover in a can, an electrode tab 111 or 121 protrudes from the upper end (refer to Figure 2c ). These electrode tabs may also be in the form of two-tab.

[0070] The support groove 222 has a shape corresponding to the cylindrical body of the battery and is formed of a magnetic material or contains a magnetic material, so that the object to be inspected can be attached to the support groove 222 by magnetic force. In addition to magnetic force, other appropriate adhesion forces can also act. A plurality of batteries entering the support groove 222 of the rotary inspection unit 220 may rotate in the support 214 for various reasons, so that the position of the upper electrode tab 111 is not constant.

[0071] Then, as the rotary inspection unit 220 rotates, a plurality of cylindrical secondary batteries 100 as objects to be inspected are transferred to a position irradiated by a first X-ray source 250 through a sensing unit 250 and a contact unit 270.

[0072] According to the selective operation of the sensing unit 250 and the contact unit 270 described in the following exemplary description, the upper electrode tabs 111 of the plurality of secondary batteries placed are aligned before reaching the X-ray source. In Figure 5a and Figure 5b , for convenience, a plurality of electrode tabs are shown in a specified direction regardless of alignment by the sensing unit and the contact unit.

[0073] When the secondary battery 100 is placed after passing through the rotary feeder 212, a first sensing unit 250 confirms the position of the upper electrode tab 111. As a result of the sensing, if the electrode tab 111 needs to be aligned, a first contact unit 270 operates to rotate the battery 100. Then, according to the sensing results of a second sensing unit 250' and a third sensing unit 250", if further alignment is needed, the second contact unit 270' or the third contact unit 270" can be made to operate.

[0074] In this embodiment, three sensing units and three contact units are respectively provided, but an appropriate number can be set according to the circumference of the secondary battery 100, the interval between a plurality of support grooves 222, the length of a contact pad 272 (refer to Figure 8 ), etc.

[0075] Figure 6 An embodiment of the sensing unit 250 installed in an X-ray inspection apparatus according to the present invention is shown.

[0076] Referring to Figure 6 , the sensing unit 250 may include: a sensor 252; a sensor bracket 254 for fixing the sensor; and a sensor support block 256 for setting the sensor bracket 254 on the inspection device 200. As the sensor, a reflective laser sensor is preferably used.

[0077] Referring to Figure 7 A method for the sensing unit 250 to sense the position of the upper end electrode tab 111 of the cylindrical secondary battery 100 will be specifically described.

[0078] Among the line segments passing through the center of the circle 160 forming the upper surface of the cylindrical battery 100, the line L1 parallel to the line connecting the two contact points of the rotation inspection unit 220 and the circle 160 and the line L2 perpendicular to it can divide the circle 160 into quadrants. Two sensors 252, 252' may be provided to sense whether there is an electrode tab 111 in the plane represented by the angle "α" in the above quadrant when the rotation inspection unit 220 rotates by R.

[0079] The angle of the sensor 252 installed in the sensing unit 250 can be adjusted according to various conditions such as the target sensing range of the sensing unit 250, for example, whether it covers the entire angle "α" of the circle 160, or the distance from the rotation inspection unit 220, sensor performance, etc. Also, the sensor 252 can also use the reflected wave reflected by the electrode tab 111 to determine how far the electrode tab is within the sensing range.

[0080] In Figure 7 , the sensor 252 is set to be able to sense whether there is an electrode tab 111 within the angle "α". A sensor 252' may be provided to correct the sensing error that may occur when the sensor 252 senses an electrode tab even at a point outside the angle "α". When the object to be inspected reaches the sensing alignment position, the sensors 252, 252' perform sensing.

[0081] Figure 6 And Figure 7 shows that the sensor bracket 254 with an angled shape inward at both ends installs the sensor 252 vertically or at a specified angle, but the sensor bracket 254 can be in the form of a flat plate without an angle, and the bending angle of the bracket 254 can be determined in different ways according to needs (refer to Figure 10 ). The sensor can also be set at any angle on the bracket. Also, the correction sensor 252' is not necessary but can be selectively adopted.

[0082] This sensing unit 250 is disposed at a position separated from the rotation inspection unit 220, and can not only sense the position, posture, or orientation of the object under inspection 100 transferred through the rotation inspection unit, but also sense other structural features of the battery. Of course, before the object under inspection reaches the X-ray source, that is, the sensing unit 250 is arranged along the rotation R direction upstream of the X-ray sources 230 and 231. Considering the angle range to be sensed, the type of sensor used, the sensing method, the rotation angle of the contact unit 270 described later, etc., two or more sensing units can be arranged along the above-mentioned transfer direction.

[0083] For example, as Figure 10 shown, in order to sense the 60-degree range ("β") and the 30-degree range ("γ") continuous with the 90-degree range ("α") respectively, three sensing units 250, 250', and 250" can be arranged along the transfer direction (i.e., the rotation R direction).

[0084] Figure 8 An embodiment of the contact unit 270 according to the present invention is shown.

[0085] Referring to Figure 8 , the contact unit 270 according to the present invention may include a contact pad 272, a backing plate 273, a locking shaft 275, a linear motion shaft 276, a bush block 278, and a spacer block 279. The above-mentioned contact pad 272 may be made of a material suitable for rotating the object under inspection 100 by contacting it, for example, polyurethane material. Such a contact pad 272 may have a concave shape to match the cylindrical shell 144 of the cylindrical battery 100.

[0086] Referring to Figures 9a to 9e will describe the manner in which the contact unit 270 rotates the object under inspection 100 when a contact command is received based on the sensing result sensed by the upstream sensing unit 250.

[0087] Figures 9a to 9e is a conceptual diagram showing the relative positions of the cylindrical battery 100, which is the object under inspection rotating R together with the rotation inspection unit 220, and the contact pad 272 of the contact unit 270.

[0088] When a contact command is received based on the sensing result of the sensing unit 250, before the corresponding battery 100 pitches and rotates at the sensing position or reaches the contact position (refer to Figure 9a ), the contact unit 270 operates through a suitable actuator such as a motor, so that the contact pad 272 extends to the contact position ( Figure 9a). This contact position can be set to a position capable of applying a contact frictional force that allows the battery located in the support groove 222 of the rotation inspection unit 220 to rotate against the adhesion force (such as magnetic force) to the support groove. Whether the contact pad operates, the operating speed, the operating time, etc. can be set by a controller (not shown).

[0089] As described above, the contact surface of the contact pad 272 with the object to be inspected can be in a concave shape. And, when the cylindrical battery enters, in order not to collide before reaching the initial contact point C1 on the contact pad 272 and also not to collide when passing through the final contact point C2 and entering, the two side corners of the contact pad 272 can be chamfered.

[0090] The cylindrical battery 100 starts to rotate from the initial contact point C1 by rotation ( Figure 9b ).

[0091] The rotation inspection unit 22 continues to rotate and continues to turn until the cylindrical battery 100 leaves the final contact point C2 ( Figure 9d ). After that, the contact pad 272 of the contact unit returns to the standby position (refer to Figure 9e ). After the battery rotates to the final contact point C2, it rotates without additional rotation due to the adhesion force (such as magnetic force) with the support groove 222.

[0092] In this case, the rotation distance or rotation angle of the cylindrical battery 100 corresponds to the contact length D of the contact pad 272. Therefore, the rotation angle of the cylindrical battery can be determined by adjusting the contact length D. For example, when the specification of the cylindrical battery is 21700, its diameter is 21 mm, and the circumference is about 65.94 mm. Therefore, a rotation distance of 65.94 mm corresponds to a rotation angle of 360 degrees. Therefore, if a rotation angle of 90 degrees is to be obtained, the contact length D of the contact pad 272 can be configured to 16.485 mm, which is one - quarter of the above - mentioned circumference. The contact pad 272 can be configured in a detachable manner.

[0093] The above - mentioned contact unit 270 is arranged upstream of the X - ray sources 230, 231 before the object to be inspected arrives at the X - ray sources, that is, along the transfer direction, and is arranged downstream of the above - mentioned sensing unit 250. For example, the contact unit 270 can be arranged near the next stop position of the battery that performs pitch rotation sensed by the sensing unit 250 (that is, the sensing alignment position). As long as it is ensured that the sensing operation for one secondary battery is performed prior to the contact operation, the sensing unit can be arranged downstream of the contact unit.

[0094] As needed, two or more contact units can be arranged along the above - mentioned transfer direction. For example, three pairs of sensing units and contact units can be arranged along the transfer direction (refer toFigure 5a , Figure 5b and Figure 10 ). The number of the sensing unit and the contact unit does not have to be the same. For example, after the position of the upper end electrode plate 111 is sensed by one sensing unit, two or more contact units can be continuously operated to achieve the required rotation angle. Since the interval of the support grooves 222 or the pitching rotation speed may limit the rotation angle that can be achieved by only one contact with the contact unit, it may be necessary to configure two or more contact units.

[0095] Hereinafter, based on the above-described embodiment of the X-ray inspection apparatus according to the present invention, the operation of the X-ray inspection apparatus, particularly the mechanism for rotating a cylindrical secondary battery as an object to be inspected to a required position, will be described.

[0096] First, as Figure 2c shown, a plurality of cylindrical secondary batteries as objects to be inspected are introduced into the inspection chamber in a state where the upper end caps are not covered through a transfer unit such as a conveyor belt. As Figure 5a and 5b shown, the plurality of secondary batteries are transferred to the rotary inspection unit 220 through the rotary feeder 212. The rotary inspection unit can rotate while repeating a rotation and a stop operation at a predetermined pitch, for example, rotate-stop-rotate. For example, during the X-ray inspection of the object to be inspected, the rotary inspection unit 220 can be in a stopped state and can be rotated again when the inspection is completed. The pitch distance corresponding to the moving distance during one rotation operation of the rotary inspection unit 220 can be predetermined and can be set to be suitable for being sensed by the sensing unit and contacting the contact unit. For example, the pitch distance can correspond to the interval between two adjacent support grooves 222.

[0097] When the cylindrical battery 100 performs a pitching rotation according to a predetermined pitch, it is aligned with the sensing unit. In this case, the sensing unit can sense the orientation of the cylindrical battery or a specific element or part of the battery, and the position of the electrode plate protruding from the upper end of the battery in this embodiment.

[0098] The objects to be inspected, for example, a group of cylindrical secondary batteries, placed in the inspection apparatus for a series of inspections are usually prepared by the same process, and thus may have the same or similar structural features. Therefore, by sensing the structural features of a group of secondary batteries, for example, the position of the protruding upper electrode plate, a preferred X-ray irradiation position can be calculated for each secondary battery in the same group.

[0099] As described above, in terms of the manufacturing process, since the upper end electrode plate and the lower end electrode plate are located at symmetric positions above and below the battery, the position of the lower end electrode plate can be known from the position of the upper end electrode plate.

[0100] Figure 10The structure in which the sensing unit 250 and the contact unit 270 of the above-described embodiment sense and rotate the cylindrical secondary battery 100 as the object to be inspected is shown. The first sensing unit, the second sensing unit, the third sensing unit, the first contact unit, the second contact unit, and the third contact unit are used. For ease of description, the states of displacement of one secondary battery (i.e., (a) to (g)) are shown in one drawing.

[0101] Referring to Figure 10 , in this embodiment, the X-ray source is configured to irradiate the left side portion of the battery as the object to be inspected (in the case of inspecting under the electrode, Figure 2c the dashed line B portion) (refer to Figure 10 , position (g)). Therefore, it is necessary to align the battery so that the electrode tab is not within the X-ray irradiation area (G).

[0102] In Figure 10 , the target inspection area in the upper surface 160 of the secondary battery is indicated by diagonal lines. Rotating the battery to irradiate the X-ray to the target inspection area will be described.

[0103] In this embodiment, as shown in the figure, the upper surface 160 is divided into a first angle range α, a second angle range β, and a third angle range γ, and the sizes of these are defined as 90 degrees, 60 degrees, and 30 degrees, respectively. The above-described first sensing unit, second sensing unit, and third sensing unit respectively sense whether the upper electrode tab 111 exists within the first angle range, the second angle range, and the third angle range.

[0104] Moreover, the first contact unit 270, the second contact unit 270', and the third contact unit 270'' are configured to rotate the battery by 90 degrees, 60 degrees, and 30 degrees, respectively. For example, the contact length D of the contact unit 270 (refer to Figure 9a ) is defined as the length for rotating the cylindrical battery 100 by 90 degrees.

[0105] It is determined whether the first contact unit 270 operates according to the position of the electrode tab 111 sensed by the first sensing unit 250. In other words, when it is sensed that the electrode tab is not in the required position, the operation of the first contact unit is commanded. In Figure 10 , since the electrode tab is within the first angle range α when the battery is in the (a) position, the first sensing unit 250 causes the operation of the first contact unit by sensing it (position (b)). The first contact unit 270 achieves a rotation angle of 90 degrees.

[0106] In the (C) position, since the electrode tab is within the second angle range β, the second sensing unit 250' causes the operation of the second contact unit 270' by sensing it (position (D)). The second contact unit 270' achieves a rotation angle of 60 degrees.

[0107] At the (e) position, since the pole piece is within the third angular range γ, the third sensing unit 250” causes the third contact unit 270” to operate by sensing it (the (f) position). The third contact unit 270” achieves a rotation angle of 30 degrees.

[0108] Then, within the support groove 222, the battery reaches the X-ray irradiation position without additional rotation. As a result, X-rays are irradiated onto the target inspection site (the shaded area).

[0109] As described above, through the sensing unit and the contact unit of the present invention, X-rays can be irradiated onto the target inspection site of the cylindrical secondary battery as the object to be inspected.

[0110] On the other hand, if at the (a) position, the pole piece 111 is within the second angular range β, the first contact unit 270 does not operate, and only the second contact unit 270’ and the third contact unit 270” operate. Similarly, if at the (a) position, the pole piece 111 is within the third angular range γ, only the third contact unit 270” operates. In all the above cases, X-rays are irradiated onto the target inspection site.

[0111] Conversely, if at the (a) position, there is no pole piece within the first angular range, the second angular range, and the third angular range, this means that the position of the pole piece does not need to be moved, and any contact unit does not operate.

[0112] As described above, by changing the sensing range of the sensing unit or adjusting the contact length of the contact pad, the number of the sensing unit and the contact unit can be changed.

[0113] Alternatively, a combination of one sensing unit and multiple contact units is also possible. That is, the rotation angle caused by each of the multiple contact units can be predetermined. After deriving the rotation angle through one sensing, the multiple contact units are selectively operated to obtain the required rotation.

[0114] Alternatively, the sensing unit and the contact unit are integrally configured to perform both the sensing operation and the contact operation.

[0115] And when the upper end electrode piece of the cylindrical secondary battery as the object to be inspected does not protrude, instead of the protruding pole piece, it is also possible to sense the structural features indicating the position of the electrode piece, such as marks displayed on the outer peripheral surface of the battery, etc.

[0116] According to the above working process, when the cylindrical secondary battery as the object to be inspected takes the preferred inspection orientation, the support groove of the rotating inspection unit usually has an adhesive force such as magnetic force, so no additional rotation of the battery will occur. Therefore, when it then reaches the irradiation positions of the first X-ray source 230 and the subsequent second X-ray source 231 as the rotating inspection unit 220 continues to rotate, the preferred inspection orientation will be maintained.

[0117] As a result, the X-ray inspection device according to the present invention can irradiate X-rays to the required parts of all batteries regardless of the orientation when the cylindrical secondary battery is placed in the inspection device, and thus good X-ray projection images can always be obtained.

[0118] As described above, specific preferred embodiments of the present invention have been shown and described. However, the present invention is not limited to the above embodiments, and various modifications and variations can be made by any ordinary technical person in the technical field to which the present invention pertains without departing from the gist and concept of the present invention as claimed.

[0119] Explanation of reference numerals

[0120] 100: Object to be inspected, secondary battery 110: Positive electrode plate

[0121] 111: Positive electrode tab 120: Negative electrode plate

[0122] 121: Negative electrode tab 200: X-ray inspection device

[0123] 210: Transfer conveyor 212: Rotary feeder

[0124] 220: Rotating inspection unit 222: Support groove

[0125] 230, 231: X-ray sources 235, 236: X-ray detectors

[0126] 250: Sensing unit 252: Sensor

[0127] 254: Sensor bracket 270: Contact unit

[0128] 272: Contact pad 273: Cushion plate.

Claims

1. An X-ray inspection device for a cylindrical secondary battery, The above X-ray inspection device includes: An inspection chamber; A transfer unit for transferring the cylindrical secondary battery into the above inspection chamber; A rotary inspection unit that rotates while holding the above cylindrical secondary battery; An X-ray source; An X-ray detector; And A release unit for releasing the inspected cylindrical secondary battery to the outside of the above inspection chamber, The X-ray inspection device for the above cylindrical secondary battery is characterized in that It includes an alignment mechanism arranged along the rotation path of the above rotary inspection unit to align the above cylindrical secondary battery, The above alignment mechanism includes: One or more sensing units for sensing the position of a specific part of the above cylindrical secondary battery; and One or more contact units that can operate between a standby position where they do not contact the above cylindrical secondary battery and a contact position where they can contact the above cylindrical secondary battery; According to the sensing result of the above sensing unit, it is determined whether the above contact unit operates. When the above cylindrical secondary battery rotates together with the above rotary inspection unit, if the above contact unit operates to the above contact position, then as the above cylindrical secondary battery continues to rotate together with the above rotary inspection unit, the above cylindrical secondary battery rotates through the contact friction force between the above contact unit and the above cylindrical secondary battery.

2. The X-ray inspection apparatus for cylindrical secondary batteries according to claim 1, characterized in that, The above cylindrical secondary battery has an electrode tab protruding from the upper end, and the above alignment mechanism aligns the above electrode tab.

3. The X-ray inspection device for cylindrical secondary batteries according to claim 1, characterized in that, Support grooves for cylindrical secondary batteries are provided at a predetermined interval around the above inspection unit, and the above cylindrical secondary battery is held in the above support grooves by adhesion.

4. The X-ray inspection device for cylindrical secondary batteries according to claim 1, wherein, The above contact unit includes a contact pad, and the contact pad has a contact surface that contacts the above cylindrical secondary battery.

5. The X-ray inspection apparatus for a cylindrical secondary battery according to claim 4, characterized in that, The rotation angle of the above cylindrical secondary battery is determined according to the length of the above contact surface.

6. The X-ray inspection apparatus for a cylindrical secondary battery according to claim 5, characterized in that, The above rotary inspection unit intermittently performs pitching rotation in the order of rotation - stop - rotation. When the above rotary inspection unit is in the stop operation state during the pitching rotation process, the above sensing unit senses the above cylindrical secondary battery.

7. The X-ray inspection device for a cylindrical secondary battery according to claim 1, characterized in that, Two or more sensing units and two or more contact units are arranged along the rotation path of the above rotary inspection unit, and the above sensing units and the above contact units are arranged alternately.

8. The X-ray inspection apparatus for a cylindrical secondary battery according to claim 1, characterized in that, Two or more of the above sensing units and two or more of the above contact units are provided. The rotation angles of the above cylindrical secondary battery with respect to the above contact units are different, and the above rotation angles are set to gradually decrease from the upstream to the downstream in the rotation direction of the above rotary inspection unit.

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