阅读说明：本技术 非破坏检查装置 (Nondestructive inspection device ) 是由 篠原正治 森田知実 染谷幸夫 小凑宏 山影阳平 于 2021-03-29 设计创作，主要内容包括：本发明提供一种可对被检查物(W)的检查对象部位进行准确的判定的非破坏检查装置(100)。所述非破坏检查装置(100)包括：搬送装置(11),对被检查物(W)进行搬送；放射线发生器(2),对被检查物(W)的多个部位照射放射线束；放射线检测器(3),隔着搬送装置(11)与放射线发生器(2)相向地设置；以及判定部(93),基于由放射线发生器(2)及放射线检测器(3)拍摄到的被检查物(W)的多个放射线透视图像中的、在检查对象部位处满足规定的基准的多个放射线透视图像是否为规定的数量以上,来判定被检查物(W)是否良好。规定的基准为检查对象部位的形状或尺寸,规定的数量少于多个放射线透视图像的数量。(The invention provides a nondestructive inspection device (100) capable of accurately judging an inspection target part of an inspection object (W). The nondestructive inspection apparatus (100) includes: a conveying device (11) for conveying the object (W) to be inspected; a radiation generator (2) for irradiating a plurality of portions of an object (W) to be examined with radiation beams; a radiation detector (3) which is provided opposite to the radiation generator (2) with a carrying device (11) therebetween; and a determination unit (93) that determines whether the object (W) is good based on whether or not a plurality of radiographic images that satisfy a predetermined criterion at the site to be examined, of the plurality of radiographic images of the object (W) imaged by the radiation generator (2) and the radiation detector (3), are greater than or equal to a predetermined number. The predetermined criterion is the shape or size of the examination target region, and the predetermined number is smaller than the number of the plurality of fluoroscopic images.)

1. A nondestructive inspection apparatus comprising:

a conveying device for conveying the object to be inspected;

a radiation generator configured to irradiate a plurality of portions of the object with radiation beams;

a radiation detector disposed opposite to the radiation generator with the carrying device interposed therebetween; and

a determination unit configured to determine whether or not the object is good based on whether or not the plurality of radiographic images satisfying a predetermined criterion at the examination target region among the plurality of radiographic images of the object captured by the radiation generator and the radiation detector are equal to or greater than a predetermined number,

the predetermined reference is the shape or size of the part to be examined,

the prescribed number is smaller than the number of the plurality of fluoroscopic images.

2. The nondestructive inspection apparatus of claim 1 wherein

The object to be inspected has a structure in which a plurality of raw materials having different widths are wound in a cylindrical shape,

the inspection target portion is an end portion of the plurality of raw materials,

the plurality of portions are in a symmetrical positional relationship in the object to be examined.

3. The nondestructive inspection apparatus according to claim 1 or 2, wherein the nondestructive inspection apparatus is a vacuum cleaner

The radiation generator and the radiation detector are provided with a plurality of groups,

each of the radiation generator and the radiation detector takes a radiographic image of a different one of the plurality of portions.

4. The nondestructive inspection apparatus of claim 2 wherein

The predetermined reference is a reference in which the distance between one end and the other end of the plurality of raw materials in the width direction is maintained at a predetermined distance.

5. The nondestructive inspection apparatus of claim 3 wherein

The predetermined reference is a reference in which the distance between one end and the other end of the plurality of raw materials in the width direction is maintained at a predetermined distance.

6. The nondestructive inspection apparatus of claim 2 wherein

The object is a battery or a capacitor formed by winding a positive electrode plate and a negative electrode plate,

the plurality of raw materials are the positive electrode plate and the negative electrode plate wider than the positive electrode plate.

7. The nondestructive inspection apparatus of claim 3 wherein

The object is a battery or a capacitor formed by winding a positive electrode plate and a negative electrode plate,

the plurality of raw materials are the positive electrode plate and the negative electrode plate wider than the positive electrode plate.

8. The nondestructive inspection apparatus of claim 4 wherein

The object is a battery or a capacitor formed by winding a positive electrode plate and a negative electrode plate,

the plurality of raw materials are the positive electrode plate and the negative electrode plate wider than the positive electrode plate.

9. The nondestructive inspection apparatus of claim 5 wherein

The object is a battery or a capacitor formed by winding a positive electrode plate and a negative electrode plate,

the plurality of raw materials are the positive electrode plate and the negative electrode plate wider than the positive electrode plate.

10. The nondestructive inspection apparatus of any one of claims 6 to 9, wherein

A tab is connected to the negative plate and,

the tab covers an end of the positive electrode plate or a portion of an end of the negative electrode plate.

Technical Field

Embodiments of the present invention relate to a nondestructive inspection apparatus.

Background

The following nondestructive inspection apparatuses are known: the object is irradiated with radiation typified by X-rays, and nondestructive inspection of the object is performed by detecting and imaging a two-dimensional distribution of the radiation attenuated by transmission through the object. The test object is, for example, a cylindrical lithium ion battery, and the inside of the test object has a structure in which positive and negative electrode plates are wound in cylindrical shapes in multiple layers.

The positive electrode plate has a width smaller than that of the negative electrode plate, and both the positive electrode plate and the negative electrode plate are wound so that an end of the positive electrode plate does not protrude from an end of the negative electrode plate. When the end of the positive electrode plate protrudes from the end of the negative electrode plate, lithium is deposited on the protruding positive electrode plate, causing a short circuit, which may cause ignition. Even when the end of the positive electrode plate does not protrude from the end of the negative electrode plate, it is desirable that a predetermined distance is maintained between the ends of the positive electrode plate and the negative electrode plate so as not to protrude due to vibration or the like. Therefore, it is necessary to check whether or not the end of the positive electrode plate protrudes from the end of the negative electrode plate in the battery and whether or not the distance between the ends of the positive electrode plate and the negative electrode plate is a predetermined distance. The inspection is performed by irradiating the upper or lower part of the battery with radiation and imaging positive and negative electrode plates alternately arranged in a cross-sectional view.

In recent years, demand for a button-type lithium ion battery has been increasing along with the wireless use of earphones and the like. Since such a battery is a small battery built in the all-wireless earphone main body, a high resolution is required for a radiographic image to be determined. In other words, in such a battery inspection, when the entire upper or lower portion is imaged, sufficient resolution cannot be obtained and it is difficult to determine the resolution, and therefore, the inspection is usually performed by irradiating one of the left side and the right side with radiation.

[ Prior art documents ]

[ patent document ]

[ patent document 1] Japanese patent application laid-open No. 2010-102901

Disclosure of Invention

[ problems to be solved by the invention ]

A metal lead called a tab (tab) extends from the negative electrode plate wound on the outermost periphery. When the battery is viewed in cross section, the tab extends from one of the side surfaces of the wound negative electrode plate toward the lower portion of the battery, is bent in an L-shape, and extends to the vicinity of the center portion of the battery. Since the tab also absorbs radiation, imaging while the tab is overlapping the end portions of the positive and negative electrode plates may become a factor that hinders the inspection. That is, in the lower right image of the tab where the battery tab is present as shown in fig. 1, the end portions of the positive and negative electrode plates are obscured by the perspective image of the tab, and it may be difficult to accurately determine whether or not the end portion of the positive electrode plate protrudes from the end portion of the negative electrode plate and whether or not the end portion of the positive electrode plate and the end portion of the negative electrode plate are spaced apart from each other by a predetermined distance.

The same applies to the case where the object to be inspected is not limited to a battery but another article such as a capacitor. That is, only by simply imaging the object to be inspected, there is a possibility that: the part to be inspected becomes a shadow of another member, or a foreign substance is mixed in to become a shadow of the part to be inspected, or the object to be inspected vibrates or inclines during transportation, and the shape or size of the part to be inspected cannot be grasped from the radioscopic image.

In order to solve the above-described problems, an object of the present embodiment is to provide a nondestructive inspection apparatus capable of accurately determining an inspection target region of an inspection target.

[ means for solving problems ]

The nondestructive inspection apparatus of the embodiment includes the following configuration.

(1) And a conveying device for conveying the object to be inspected.

(2) And a radiation generator for irradiating the radiation beams to a plurality of portions of the object.

(3) And a radiation detector disposed opposite to the radiation generator with the carrying device therebetween.

(4) And a determination unit configured to determine whether the object is good or not, based on whether or not the plurality of fluoroscopic images satisfying a predetermined reference at the examination target region among the plurality of fluoroscopic images of the object captured by the radiation generator and the radiation detector is equal to or greater than a predetermined number.

(5) The predetermined reference is the shape or size of the examination target region.

(6) The prescribed number is smaller than the number of the plurality of fluoroscopic images.

The nondestructive inspection apparatus of the embodiment may further include the following structure.

(1) The object to be inspected includes a structure in which a plurality of raw materials having different widths are wound in a cylindrical shape, the inspection target portion is an end portion of the plurality of raw materials, and the plurality of portions are in a symmetrical positional relationship in the object to be inspected.

(2) The radiation generator and the radiation detector are provided in plural sets, and each set of the radiation generator and the radiation detector captures a radiographic image of a different one of the plural portions.

(3) The predetermined reference is a reference in which the distance between one end and the other end of the plurality of raw materials in the width direction is maintained at a predetermined distance.

(4) The test object is a battery or a capacitor formed by winding a positive electrode plate and a negative electrode plate, and the plurality of materials include the positive electrode plate and the negative electrode plate that is wider than the positive electrode plate.

(5) A tab is connected to the negative electrode plate, and the tab covers an end of the positive electrode plate or a portion of an end of the negative electrode plate.

Drawings

Fig. 1 is a perspective sectional view of an object to be examined according to the embodiment.

Fig. 2 is a perspective view showing an object to be inspected according to the embodiment.

Fig. 3 is a plan view showing a nondestructive inspection apparatus according to an embodiment.

Fig. 4 is a functional block diagram showing control of the embodiment.

Fig. 5 is a flowchart showing the operation of the nondestructive inspection apparatus according to the embodiment.

Fig. 6 (a) and 6 (b) are diagrams showing examples of imaging in the embodiment.

[ description of symbols ]

100: nondestructive inspection device

1: conveying mechanism

11: rotary conveying device

111: working table

112: holding part

113: concave part

12: carrying-in device

121: transfer device

13: carrying-out device

131: transfer device

2: radiation generator

3: radiation detector

4: shielding box

41: carrying-in port

42: conveying outlet

9: control unit

91: image pickup command unit

92: storage unit

93: determination unit

H: holding rack

N: negative plate

P: positive plate

T: joint

W: object to be inspected

Detailed Description

[1. embodiment ]

[1-1. Structure of embodiment ]

Hereinafter, an object to be inspected and a nondestructive inspection apparatus according to an embodiment will be described with reference to the drawings. In the present embodiment, one object is inspected for whether or not the end of the positive electrode plate protrudes from the end of the negative electrode plate and whether or not the distance between the ends of the positive electrode plate and the negative electrode plate is a predetermined distance by first imaging the left side and the right side on the upper portion of the object and then imaging the left side and the right side on the lower portion of the object.

[ test object ]

The test object W is not particularly limited as long as it is cylindrical and includes a winding structure including a plurality of raw materials inside, and the test object W of the present embodiment is a cylindrical lithium ion battery having a structure in which a positive electrode plate P and a negative electrode plate N are wound in a cylindrical shape in a plurality of layers inside a case. The positive electrode plate P is shorter than the negative electrode plate N in the width direction and is wound so as not to protrude from the negative electrode plate N. More preferably, the winding is performed so that a predetermined distance is maintained between the ends of the two. The predetermined interval may be a value or a numerical range. As shown in the right side of the lower portion of fig. 1, a lead called a tab T is connected to the negative electrode plate N wound around the outermost periphery of the wound structure, and in the present embodiment, the lead extends from the side surface of the negative electrode plate N on the outermost periphery toward the lower portion of the battery, is bent in an L shape, and extends to the vicinity of the center portion of the battery. That is, the joint T is housed inside the test object W. Although not shown in fig. 1, a separator made of resin or the like is interposed between the positive electrode plate P and the negative electrode plate N.

As shown in the perspective view of fig. 2, the object W is placed on a cylindrical holder H larger than the object W in the radial direction. More specifically, a recess is provided on the upper surface of the holder H, and the lower portion of the object W is fixed to the recess. Since the holder H is made of, for example, resin, even if the object W is fixed to the recess, the lower portion of the object W can be subjected to the radiation inspection. In the present embodiment, the test object W is not directly conveyed, but the holder H on which the test object W is placed is conveyed.

[ nondestructive inspection apparatus ]

The nondestructive inspection apparatus 100 irradiates the object W with radiation and detects the radiation transmitted through the object W. Based on the detection result, the nondestructive inspection apparatus 100 generates a fluoroscopic image of the inspection object W. As shown in fig. 3, the nondestructive inspection apparatus 100 includes: a conveying mechanism 1 for conveying a cylindrical holder H holding an object W to be inspected on the upper surface thereof; a radiation generator 2 and a radiation detector 3 that capture a fluoroscopic image of an object W to be examined; and a shielding box 4 for shielding the radiation. The nondestructive inspection apparatus 100 further includes a control unit 9 (see fig. 4) that controls the operation and direction of the transport mechanism 1, the radiation generator 2, and the radiation detector 3.

The conveying mechanism 1 is a mechanism for conveying the holder H on which the test object W is placed. The conveyance mechanism 1 includes: a rotary conveyance device 11 constituting a conveyance path for inspection of an object to be inspected W; a carrying-in device 12 provided on a carrying-in side of the rotary conveyance device 11; and a carrying-out device 13 provided on the carrying-out side of the rotary conveyance device 11. The loading device 12 and the unloading device 13 include a transfer device 121 and a transfer device 131, respectively.

The loading device 12 and the unloading device 13 are, for example, chain conveyors or belt conveyors. The loading device 12 loads the holder H on which the test object W is placed into the rotary conveyance device 11 via the transfer device 121. That is, the transfer device 121 is provided between the loading device 12 and the rotary conveyance device 11. The carry-out device 13 carries out the holder H on which the object W to be inspected having been subjected to the nondestructive inspection in the rotary conveyance device 11 is placed from the rotary conveyance device 11 via the transfer device 131. That is, the transfer device 131 is provided between the carrying-out device 13 and the rotary conveyance device 11.

The transfer device 121 and the transfer device 131 have substantially the same configuration, and include, for example, wheels including a holding mechanism capable of holding the holders H. That is, the transfer device 121 includes a plurality of recesses at equal intervals along the outer periphery thereof, and is rotated in the horizontal direction by a motor not shown. A holding mechanism, not shown, is provided in the recess, and the holder H can be held or released in the recess by the holding mechanism. The transfer device 121 sequentially holds or releases the holders H while rotating in the horizontal direction, thereby gradually transferring the holders H from the loading device 12 to the rotary conveyance device 11. Similarly, the transfer device 131 includes a plurality of recesses at equal intervals along the outer periphery thereof, and is rotated in the horizontal direction by a motor not shown. A holding mechanism, not shown, is provided in the recess, and the holder H can be held or released in the recess by the holding mechanism. The transfer device 131 sequentially holds or releases the holders H while rotating in the horizontal direction, thereby gradually transferring the holders H from the rotary conveyance device 11 to the carry-out device 13. The holding mechanism is realized by, for example, an adsorption mechanism using vacuum or magnetic force or a mechanical clamping mechanism, but in the present embodiment, an adsorption mechanism using vacuum or magnetic force is used.

The rotary conveyance device 11 includes a disk-shaped table 111 and an annular holding portion 112 provided on the table 111 to stand substantially concentrically with the table 111. A motor, not shown, is provided on the table 111, and the table 111 is rotatable in the horizontal direction together with the holding portion 112. The holding portion 112 is provided with a plurality of recesses 113 at equal intervals along its outer periphery. A holding mechanism, not shown, is provided in the recess 113, and the holder H can be held or released in the recess 113 by the holding mechanism. That is, the rotary conveyance device 11 can sequentially convey the holders H carried in from the carrying-in device 12 by the transfer device 121 on the table 111. The holding mechanism is realized by, for example, an adsorption mechanism using vacuum or magnetic force or a mechanical clamping mechanism, but in the present embodiment, an adsorption mechanism using vacuum or magnetic force is used.

Inside the annular holding portion 112, two radiation generators 2 are provided back to back. The radiation generator 2 irradiates the test object W sequentially conveyed in front thereof with a radiation beam. The radiation beam is a beam of radiation that expands in a pyramid shape with a focal point as a vertex. The radiation is, for example, X-rays. The radiation generator 2 is, for example, an X-ray tube.

The radiation detector 3 is disposed opposite to the focal point of each radiation generator 2. That is, the two sets of the radiation generator 2 and the radiation detector 3 face each other with the annular holding portion 112 interposed therebetween. The radiation detector 3 detects a two-dimensional distribution of radiation intensity that is weakened by a transmission path of radiation, and outputs transmission data proportional to the radiation intensity. The radiation detector 3 includes, for example, an Image Intensifier (i.i.), a camera, or a Flat Panel Display (FPD).

The two sets of the radiation generator 2 and the radiation detector 3 are different in height from each other in imaging the object W, and the set on the carry-in device 12 side is located at a height at which the upper part of the object W can be imaged, and the set on the carry-out device 13 side is located at a height at which the lower part of the object W can be imaged. The radiation generator 2 and the radiation detector 3 on the loading device 12 side are referred to as a radiation generator 2a and a radiation detector 3a, respectively, and the radiation generator 2 and the radiation detector 3 on the unloading device 13 side are referred to as a radiation generator 2b and a radiation detector 3b, respectively. Both the two sets of the radiation generator 2 and the radiation detector 3 are set to be able to image one side of the upper or lower portion of the object W.

The shield box 4 surrounds a part of the transport mechanism 1, the radiation generator 2, and the radiation detector 3, and shields the radiation. The shielding box 4 is made of a material that shields radiation, such as lead. The shield case 4 has a rectangular parallelepiped shape, for example. The shield case 4 is provided with: the inspection apparatus includes a carrying-in port 41 for carrying in the holder H holding the inspection object W, a carrying-out port 42 for carrying out the inspection object W inside the shield box 4 to the outside of the shield box 4, the carrying-in port 41 being provided on the way of the carrying-in device 12, and the carrying-out port 42 being provided on the way of the carrying-out device 13.

As shown in fig. 4, the controller 9 controls the operations and directions of the transport mechanism 1, the radiation generator 2, and the radiation detector 3 in order to transport and inspect the object W. For example, the conveying mechanism 1 may be controlled based on the determination result of the determination unit 93 described later. The control Unit 9 is a so-called computer, and includes a Memory (storage) such as a Hard Disk Drive (HDD) or a Solid State Drive (SSD), a Random Access Memory (RAM), a Central Processing Unit (CPU), and a Drive circuit. The memory stores, for example, a program or data for controlling each configuration. The program is developed in the RAM and the data is temporarily stored. The CPU processes the program, and the driver circuit supplies power to each component according to the processing result.

The control unit 9 includes, in particular, an imaging instruction unit 91, a storage unit 92, and a determination unit 93. The imaging command unit 91 causes the radiation generator 2 to irradiate the object W with a radiation beam. More specifically, the left and right sides of the upper or lower part of the object W are irradiated with radiation beams. Further, in the present embodiment, four radioscopic images (upper left, upper right, lower left, and lower right in fig. 1) are generated by imaging four positions, i.e., upper left and right sides, and lower left and right sides, which are in a symmetrical positional relationship in one object W, using two radiation generators 2a and 2 b. Each of the four fluoroscopic images is set as an examination target region including the object W. The inspection target portions in the present embodiment are the end portions of the positive electrode plate P and the negative electrode plate N. The symmetrical positional relationship in the object W means the relationship between the left and right sides of the object W or the relationship between the upper and lower portions of the object W. As in the symmetrical positional relationship of the present embodiment, the case where the left side and the right side in the symmetrical positional relationship are provided in two sets in the upper portion and the lower portion, respectively, is also included. In this case, the upper and lower portions in the symmetrical positional relationship may be considered to be present in two groups on the left and right sides.

The storage unit 92 stores a predetermined reference to which the determination unit 93 determines. The predetermined reference in the present embodiment is that the positive electrode plate P does not protrude from the negative electrode plate N, and the interval between the end of the positive electrode plate P and the end of the negative electrode plate N is a predetermined interval, or both.

The determination unit 93 determines whether the object W is good or not based on whether or not the four fluoroscopic images detected by the radiation detector 3 satisfy a predetermined criterion. That is, the determination unit 93 determines whether or not each of the inspection target regions in the four fluoroscopic images satisfies a predetermined criterion. When the radioscopic image is unclear due to the influence of the tab T or the like, that is, when the positive electrode plate P and the negative electrode plate N cannot be distinguished by the shading value, the determination unit 93 determines that the radioscopic image does not satisfy the predetermined criterion. In the present embodiment, at least one radioscopic image is unclear due to the influence of the junction T as shown in fig. 1, and does not satisfy a predetermined standard. When the positive electrode plate P and the negative electrode plate N cannot be distinguished from each other by the shade value, for example, when the positive electrode plate P does not protrude from the negative electrode plate N, the determination unit 93 determines that the predetermined criterion is satisfied. More specifically, it is determined whether or not the positive electrode plate P protrudes from the negative electrode plate N, based on the shape of the site to be inspected, that is, based on the positional relationship between the ends of the positive electrode plate P and the negative electrode plate N. Even when the positive electrode plate P and the negative electrode plate N are not extended, the double determination may be made based on whether or not the distance between the end of the positive electrode plate P and the end of the negative electrode plate N is a predetermined distance. In this case, the distance between the ends of the positive electrode plate P and the negative electrode plate N is measured to determine whether the distance is a predetermined distance. In this way, whether the object W is good or not is determined by whether or not a predetermined number of images, for example, three or more images, out of the four fluoroscopic images satisfy a predetermined criterion. In the present embodiment, since at least one of the fluoroscopic images is unclear, the predetermined number is smaller than the number of the plurality of fluoroscopic images.

[1-2. effects of embodiments ]

The procedure of carrying and inspecting the test object W in the present embodiment will be described with reference to the flowchart of fig. 5 as a center.

(1) Carrying-in process

As a premise, the holders H on which the test objects W are placed are arranged on the conveyance path of the loading device 12 until just before the transfer device 121. When the conveying mechanism 1 is driven by the control of the controller 9, the holders H are sequentially transferred from the loading device 12 to the rotary conveying device 11 (step S01). More specifically, first, the concave portion of the transfer device 121 sucks and holds the holder H conveyed by the carrying-in device 12. Next, the concave portions 113 of the holding portions 112 of the rotary conveyance device 11 hold the holders H by suction, while the transfer device 121 releases the holders H. Thus, the holders H are transferred from the transfer device 121 to the rotary conveyance device 11, and conveyed on the table 111 rotating together with the holding portion 112 while being held in the recesses 113.

(2) Upper part image pickup process

The upper part of the test object W placed on the holder H conveyed on the table 111 is imaged by the radiation generator 2a and the radiation detector 3a provided on the loading device 12 side. More specifically, the radiation generator 2a is controlled by the imaging command unit 91 to first image the right side of the upper part as shown in fig. 6 (a), and then image the left side of the upper part as shown in fig. 6 (b) (step S02). The radiation detector 3a outputs these radioscopic images to the control section 9.

(3) Lower imaging step

The object W subjected to the nondestructive inspection in step S02 is further conveyed on the table 111 of the rotary conveyance device 11, and the lower portion thereof is imaged by the radiation generator 2b and the radiation detector 3b provided on the carrying-out device 13 side. More specifically, the radiation generator 2b is controlled by the imaging instruction unit 91 to first image the left side of the lower portion as shown in fig. 6 (a), and then image the right side of the lower portion as shown in fig. 6 (b) (step S03). The radiation detector 3b outputs these radioscopic images to the control section 9.

(4) Determination step

The determination section 93 of the control section 9, which receives the four radioscopic images in total from the radiation detector 3a and the radiation detector 3b, determines whether the object W is good or not based on the four radioscopic images (step S04). More specifically, it is determined whether or not each of the four fluoroscopic images satisfies a predetermined criterion, and if the predetermined number of fluoroscopic images is equal to or greater than the predetermined number and three or more fluoroscopic images satisfy the predetermined criterion in the present embodiment, it is determined that the object W is a good product. Whether or not the predetermined criterion is satisfied is determined based on whether or not the positive electrode plate P protrudes from the negative electrode plate N, for example, but when the radiographic image is unclear due to the influence of the tab T or the like, that is, when the shading values of the positive electrode plate P and the negative electrode plate N cannot be distinguished, it is determined that the radiographic image does not satisfy the predetermined criterion. For example, when two of the four fluoroscopic images are unclear, the object W is determined to be a defective product because it is determined that three or more fluoroscopic images do not satisfy the predetermined criterion. In this way, the determination unit 93 determines whether or not the positive electrode plate P and the negative electrode plate N are distinguishable from each other by the shade value, and further determines whether or not the positive electrode plate P protrudes from the negative electrode plate N based on the positional relationship between the end portions of the two when the positive electrode plate P and the negative electrode plate N are distinguishable from each other, thereby determining whether or not the object W is a good product. Even when the positive electrode plate P does not protrude from the negative electrode plate N, the double determination may be made based on whether or not the distance between the end of the positive electrode plate P and the end of the negative electrode plate N is the predetermined distance stored in the storage unit 92. In this case, whether or not the interval is a predetermined interval is determined by measuring the interval between the ends of the two divided by the shade value.

In the present embodiment, the determination unit 93 determines that the object W is a defective product when three or more of the four fluoroscopic images do not satisfy the predetermined reference. The test object W to be a defective product may be transferred to a not-shown recovery conveyor by controlling the transfer device 131 by the control unit 9, and recovered in a recovery box provided at the front end of the recovery conveyor.

(5) Carrying out process

Finally, the holders H of the inspection target objects W that have finished the inspection are sequentially transferred from the rotary conveyance device 11 to the carry-out device 13 (step S05). More specifically, first, the concave portion of the transfer device 131 sucks and holds the holder H conveyed on the table 111. On the other hand, the concave portion 113 of the holding portion 112 of the rotary conveyance device 11 releases the holder H. Thereby, the transfer device 131 continues to rotate in the horizontal direction while holding the holders H by suction, and is released from the carry-out device 13.

As described above, the test objects W placed on the holders H are sequentially conveyed and inspected in steps S01 to S05.

[1-3. effects of the embodiment ]

(1) In the present embodiment, a plurality of portions of one object W are imaged, and whether the object W is good or not is determined based on whether or not a predetermined number or more of radioscopic images among the plurality of radioscopic images satisfy a predetermined criterion at the inspection target portion. Thus, even when one of the plurality of fluoroscopic images does not satisfy the predetermined criterion for reasons such as unclear, the other fluoroscopic images satisfy the predetermined criterion, thereby preventing the object W from being a defective product even though it is a good product.

(2) In the case where the test object W includes a structure in which a plurality of materials having different widths are cylindrically wound inside, for example, a structure in which a positive electrode plate P and a negative electrode plate N wider than the positive electrode plate P are cylindrically wound, the width of the positive electrode plate P and the width of the negative electrode plate N are determined at the stage of manufacturing the test object W, and therefore, the interval between the ends of the two electrode plates in one of the upper portion and the lower portion is also determined from the interval between the ends of the two electrode plates in the other. Therefore, if the upper or lower portion of the object W is imaged, it can be determined whether the object W is good or not. Further, the positive electrode plate P and the negative electrode plate N are wound in a cylindrical shape in a plurality of layers inside the test object W, and therefore, are substantially bilaterally symmetrical in a cross-sectional view. In this case, it is possible to determine whether the inspection object W is good or not by imaging one of the left side and the right side of the upper portion and the lower portion of the inspection object W.

In the present embodiment, it is not always necessary to photograph the upper left side, the upper right side, the lower left side, and the lower right side of one object W to be inspected, and whether the object W is good or not is determined based on the four radioscopic images. Thus, even if either the upper or lower radioscopic image is unclear, for example, due to the influence of the joint T, and even if the winding structure inside the object W is not completely bilaterally symmetrical due to winding variation or the like, a high-precision quality inspection can be performed.

(3) In the present embodiment, two sets of the radiation generator 2 and the radiation detector 3 are used to image the upper left side, the upper right side, the lower left side, and the lower right side of one object W to be examined, and whether the object W is good or not is determined based on the four radioscopic images. This allows the inspection speed of the object W to be increased by only taking two images with one set. Even if the joint T is reflected on the right side of the lower portion of the object W, for example, and the radiographic image is unclear due to its influence, it is possible to determine whether or not the remaining three of the four radiographic images satisfy a predetermined criterion. Thus, the object W to be inspected can be produced to have a strict quality level satisfying a predetermined standard at three of four places, for example.

(4) In the present embodiment, the predetermined criterion that each of the radioscopic images should satisfy is defined as maintaining a predetermined distance between the end of the positive electrode plate P and the end of the negative electrode plate N. Thus, compared to the case where the positive electrode plate P does not protrude from the negative electrode plate N, even if the positive electrode plate P and the negative electrode plate N are displaced in the width direction by vibration or the like after the inspection, the possibility that the positive electrode plate P protrudes from the negative electrode plate N can be reduced.

[2 ] other embodiments ]

In the present specification, a plurality of embodiments of the present invention have been described, but the embodiments are presented as examples and are not intended to limit the scope of the invention. The above-described embodiments can be implemented in various other forms, and various omissions, substitutions, and changes can be made without departing from the scope of the invention. The above-described embodiments and modifications thereof are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalent scope thereof.

(1) In the above embodiment, the joint T is housed in the object W and inspected, but the present invention is not limited thereto. For example, it is also possible to inspect whether or not foreign matter is erroneously mixed in the object W during the manufacturing process.

(2) The inspection target portions in the above embodiment are the end portions of the positive electrode plate P and the negative electrode plate N, but are not limited thereto. For example, when a crack or deformation is likely to occur near the center of the object W in the vertical direction, the vicinity of the center of the wound structure may be set as the inspection target region. In addition, the end portions of the positive electrode plate P and the negative electrode plate N may be imaged by one of the radiation generators 2 in the above-described embodiment, and the vicinity of the center of the object W may be imaged by the other. In this case, the inspection target portion near the center has a shape of a wound structure such as deformation or cracking of the wound structure.

(3) In the above embodiment, a small-sized lithium ion battery is used as the object W to be inspected, but a large-sized object W may be used. In this case, since it is not necessary to increase the resolution of the fluoroscopic images, it is also possible to capture the fluoroscopic images so that the left and right sides of the upper or lower portion are limited to one fluoroscopic image. The test object W is not limited to a battery, and may be used for testing a capacitor including a structure in which a positive electrode plate and a negative electrode plate are cylindrically wound. The plurality of wound materials are not limited to the positive electrode plate and the negative electrode plate of the battery or the capacitor. For example, only a metal thin film may be used. Further, the object W is not limited to an electronic component having a winding structure. If the article has a plurality of inspection target portions, the same inspection as in the above embodiment can be performed.

(4) In the above embodiment, two sets of the radiation generator 2 and the radiation detector 3 are used, but one set may be used. In contrast to the case of imaging with two sets, it takes time to image a plurality of portions with one set, and therefore it is preferable to slow down the conveyance speed. In the case of imaging a plurality of sites by one set, it is only necessary to image two sites, i.e., the upper and lower parts or the left and right sides of the object W by using the symmetry of the winding structure.

(5) In the above embodiment, two sets of the radiation generator 2 and the radiation detector 3 are used, but the number of the radiation generator and the radiation detector may be set according to the number of the portions to which the radiation beams are irradiated. For example, when the radiation beams are irradiated to four positions of the object W as in the above-described embodiment, four sets of the radiation generator 2 and the radiation detector 3 may be provided. This makes it possible to further increase the inspection speed of the object W, because only one pair of images is used to capture images at one location.

(6) In the above embodiment, the test object W to be regarded as a defective product may be placed on the recovery conveyor by the transfer device 131 and recovered in the recovery box, but may be placed on a non-illustrated reloading conveyor extending from the transfer device 131 to the loading device 12, reloaded into the loading device 12, and further transferred to the rotary transport device 11 to perform reinspection.

(7) The conveying mechanism 1 for conveying the test object W of the above embodiment may be configured to include a linear conveyor as a conveying device instead of the rotary conveying device 11.

(8) The test object W in the above embodiment is conveyed in a state of being placed on the holder H, but may be directly conveyed without passing through the holder H.