Layering device

Abstract

Provided is a layering device for placing and layering a plurality of sheet-like plates, with which the appropriateness of the placement position of the sheet-like plates immediately after being placed can be accurately determined. The present invention comprises a control unit (8) that determines, on the basis of first image data and second image data, the appropriateness of the placement positions of a negative electrode plate (Ea) and a positive electrode plate (Eb). The control unit (8), for example: acquires first outer shape size information of a first claw member (22a) on the basis of the first image data; thereafter, executes a comparison computation between the first outer shape size information and first actual outer shape size information, which is the actual outer shape size of the first claw member (22a), to calculate a first correction value (Cv1) for matching the first outer shape size information with the first actual outer shape size information; and by using the first correction value (Cv1), determines the appropriateness of the placement position of the negative electrode plate (Ea) on the basis of post-first correction placement position information obtained by correcting first placement position information of the negative electrode plate (Ea).

Description

Stacking Device

[0001] The present invention relates to a stacking device for placing and stacking a plurality of sheets.

[0002] Stacking devices that stack multiple plates in sequence have been known. For example, Patent Document 1 discloses an electrode stack manufacturing device (stacking device) that stacks two types of plates, each consisting of a negative electrode plate (negative electrode plate) and a positive electrode plate (positive electrode plate), alternately with a separator interposed therebetween. The device stacks the negative and positive electrode plates in sequence by folding a long strip of separator zigzag on a lifting stage (loading table) so that the negative and positive electrode plates are positioned between the folded portions of the separator. Such a stacking device typically includes an imaging device, such as a digital camera, above the stacking table. The imaging device captures image data of the plate (negative electrode plate or positive electrode plate) immediately after it is placed on the stacking table via the separator. The imaging device then determines the appropriate placement position of the plate on the stacking table based on the image data.

[0003] Here, when the vertical position of the subject (plate) relative to the imaging means changes, the image of the subject in the acquired image data is enlarged or reduced depending on the distance between the imaging means and the subject, because the angle of view of the imaging means is constant. For example, if the position of the plate (negative or positive electrode plate) relative to the imaging means is closer to the imaging means than a predetermined position (i.e., higher than the predetermined position), the image of the plate in the image data is captured in a state enlarged compared to the set scale. Also, if the position of the plate (negative or positive electrode plate) relative to the imaging means is farther away from the imaging means than a predetermined position (i.e., lower than the predetermined position), the image of the plate in the image data is captured in a state reduced compared to the set scale. As a result, when the placement position of a plate (negative or positive plate) is grasped based on image data obtained by the imaging means, the deviation between a predetermined reference placement position and the grasped placement position is calculated, and the appropriateness of the placement position of the plate is judged based on this deviation, the deviation will include errors arising from differences in scale depending on the vertical position of the plate relative to the imaging means, making it difficult to accurately judge the appropriateness of the placement position of the plate.

[0004] For this reason, in conventional stacking devices, each time a plate (negative or positive plate) is placed on the stacking table via a separator, the stacking table is lowered a predetermined distance (specifically, the sum of the thickness of the negative or positive plate and the thickness of the separator), so that the position of the top surface of the plate relative to the imaging means is always approximately constant.

[0005] Japanese Patent Application Laid-Open No. 2019-215967

[0006] In the conventional lamination device described above, the position of the top surface of a plate (negative or positive electrode plate) immediately after it is placed on the lamination table is prone to some variation due to factors such as tolerances for manufacturing errors in each plate and air entrapment that occurs when the separator is folded zigzag. Here, as the number of plates (negative or positive electrode plates) placed on the lamination table increases, the variations in the top surface position may accumulate without canceling each other out. As a result, as described above, even if the lamination table is lowered a predetermined distance each time a plate is placed on the lamination table, it is difficult to maintain a substantially constant position of the top surface of the plate relative to the imaging means, and it may be difficult to accurately determine the appropriate placement position of the plate.

[0007] The present invention has been made in consideration of the current problems described above, and its object is to provide a stacking device that places and stacks multiple sheet plates, and that can accurately determine the appropriate placement position of the sheet plate immediately after it is placed.

[0008] The problem to be solved by the present invention is as described above, and the means for solving this problem will now be described.

[0009] That is, a stacking device according to a first aspect of the present invention is a stacking device for placing and stacking a plurality of sheet metal plates, and includes a stacking table for holding the sheet metal plates to be stacked, a transfer means for placing the sheet metal plates on the upper surface of the stacking table, an imaging means for acquiring image data of the stacking table on which the sheet metal plates are placed from above each time the sheet metal plates are placed by the transfer means, and a control means for determining the appropriateness of the placement position of the sheet metal plates based on the image data, and the stacking table includes a tracking means for tracking the upper surface of the sheet metal plates immediately after they are placed on the stacking table. The control means acquires outer size information of the tracking means based on the image data, and then performs a comparison operation between the outer size information and actual outer size information, which is the actual outer size of the tracking means, to calculate a correction value for matching the outer size information to the actual outer size information, and acquires placement position information of the sheet based on the image data, and determines the appropriateness of the placement position of the sheet based on corrected placement position information obtained by correcting the placement position information using the correction value. By having this configuration, the stacking device of the present invention can, when a plate is placed on the stacking table, enlarge or reduce the image of the plate in the image data due to variations in the position of the top surface of the plate, and even if the plate placement position information obtained based on the image data contains errors arising from differences in scale, by correcting the placement position information using a correction value, corrected placement position information that is at least close to the actual value can be obtained, and the corrected placement position information can be used to accurately determine the appropriate placement position of the plate.

[0010] A second aspect of the present invention relates to a stacking device according to the first aspect, characterized in that the stacking table is lowered a predetermined distance each time a plate is placed on the stacking table, and the control means uses the compensation value to compensate for the lowering distance. With this configuration, even if variations occur in the position of the top surface of a plate placed on the stacking table, the compensation value can be used to compensate for the lowering distance, thereby lowering the stacking table to an appropriate position that corresponds to the variations. This more stably maintains a substantially constant position of the top surface of the plate relative to the imaging means. Therefore, errors arising from differences in scale can be more reliably eliminated from the plate placement position information acquired based on image data, and the appropriate placement position of the plate can be more accurately determined.

[0011] In addition, a stacking device according to a third aspect of the present invention is the same as in the second aspect, wherein the control means adjusts the lowering distance each time a plate is placed on the stacking table. With this configuration, even if variations occur in the position of the upper surface of the plate placed on the stacking table, it is possible to prevent the variations from accumulating each time a plate is placed on the stacking table, and it is possible to more accurately determine the appropriate placement position of the plate.

[0012] A stacking device according to Aspect 4 of the present invention is any of Aspects 1 to 3, characterized in that the following means is a claw member that presses down from above to maintain the placement position of the plate placed on the stacking table. In this way, the stacking device according to the present invention utilizes a claw member that follows the top surface of the plate immediately after it is placed on the stacking table and is provided to maintain the placement position of the plate, so that there is no need to separately provide a device with a complex mechanism, and the present invention can be realized at lower cost.

[0013] A stacking device according to a fifth aspect of the present invention is any of the above-mentioned aspects 1 to 4, characterized in that the plurality of sheets are made of two types of components, negative and positive plates, and are placed on the upper surface of the stacking table by the moving means so that the negative and positive plates are alternately arranged with a separator interposed therebetween. By applying the stacking device according to the present invention to an apparatus for manufacturing a stacked battery by alternately stacking two types of sheets, made of negative and positive plates, with a separator interposed therebetween, it is possible to accurately determine the appropriate placement positions of the negative and positive plates immediately after they are placed on the stacking table, and to manufacture a high-quality stacked battery.

[0014] A lamination device according to a sixth aspect of the present invention is any of the first to fourth aspects, wherein the separator is made of a long, strip-shaped member, and the lamination device further includes a separator supply means disposed above the lamination table and adapted to supply the separator to an upper surface of the lamination table while moving back and forth horizontally and in one direction relative to the lamination table. Even in such a lamination device that folds a long, strip-shaped separator zigzag on a loading table and stacks a plurality of sheets of negative and positive electrode plates alternately in order so as to be positioned between the folded portions of the separator, the lamination device according to the present invention can accurately determine the appropriate placement positions of the negative and positive electrode plates immediately after they have been placed on the lamination table.

[0015] The present invention has the following effects: That is, the stacking device according to the present invention can accurately determine the appropriateness of the placement position of a sheet immediately after it has been placed.

[0016] 4A is a front view showing the overall configuration of a stacking device according to an embodiment of the present invention. FIG. 4B is a front view showing the state of the stacking table after a negative electrode plate has been placed on the stacking table at the first stacking position. FIG. 4C is a front view showing the state of the stacking device immediately after the start of the stacking operation. FIG. 4A is a front view showing the state of the stacking device immediately after the start of the stacking operation. FIG. 4B is a front view of the stacking device with a negative electrode plate placed on the stacking table. FIG. 4C is a front view of the stacking device with the stacking table lowered based on first lowering distance information. FIG. 5A is a front view of the stacking device with the stacking table horizontally moved to the second stacking position. FIG. 5B is a front view of the stacking device with a positive electrode plate placed on the stacking table. FIG. 5C is a front view of the stacking device with the stacking table lowered based on second lowering distance information. FIG. 5B is a front view of the stacking device with the stacking table lowered based on second lowering distance information. FIG. 5C is a front view of the stacking device with the stacking table lowered based on second lowering distance information. FIG. 5C is a front view of the stacking device with the stacking table horizontally moved to the second stacking position. FIG. 5C is a front view of the stacking device with the stacking table lowered based on second lowering distance information. FIG. 5D is a front view of the stacking device with the stacking table lowered based on second lowering distance information. FIG. 5D is a front view of the stacking device with the stacking table horizontally moved to the second stacking position. FIG. 5D is a front view of the stacking device with the stacking table lowered based on second lowering distance information. FIG. 5E is a diagram illustrating first image data acquired by a first imaging unit. FIG. 5F is a flowchart showing a series of steps when performing suitability determination control to determine the suitability of the electrode plate placement position.

[0017] Next, one embodiment of the present invention will be described with reference to Figures 1 to 7. For convenience, the following description will define the front-rear direction, left-right direction, and up-down direction of the stacking device 1 using the directions of arrows shown in Figures 1, 3, 5A, and 6. In the following description, the direction of arrow A in Figures 1, 3, 5A, and 6 will be defined as the direction of reciprocating movement of the stacking table 2.

[0018] [Overall Configuration of Stacking Device 1] First, the overall configuration of a stacking device 1 embodying the present invention will be described with reference to FIGS. 1 to 3. FIG.

[0019] The stacking device 1 in this embodiment is a device for manufacturing a stacked battery such as a lithium ion secondary battery, and is a device for stacking two types of electrode plates E, each consisting of a negative electrode plate Ea and a positive electrode plate Eb, alternately placed with a separator S interposed therebetween. Here, the electrode plates E consisting of the negative electrode plate Ea and the positive electrode plate Eb are an example of a sheet plate according to the present invention.

[0020] The stacking device 1 described below is one example of the stacking device according to the present invention, and is not limited to this. That is, the stacking device according to the present invention is a device for placing and stacking a plurality of sheet plates, and the objects (sheet plates) to be stacked are not limited to electrode plates E, and are not limited to being stacked one after the other with separators S interposed therebetween. Furthermore, the separators S are not limited to long strip-shaped separators, and may be sheet-shaped separators.

[0021] 1 , the stacking device 1 mainly includes a stacking table 2 that is provided so as to be reciprocable horizontally and in one direction (left-right direction in this embodiment) between a first stacking position P1 and a second stacking position P2 that are spaced apart from each other, a separator supply unit 3 that is provided above the stacking table 2 approximately midway between the first stacking position P1 and the second stacking position P2, a first transfer unit 4 that is provided at the first stacking position P1, and a second transfer unit 5 that is provided at the second stacking position P2. The stacking device 1 also includes a first imaging unit 6 that is provided above the stacking table 2 at the first stacking position P1, and a second imaging unit 7 that is provided above the stacking table 2 at the second stacking position P2, and a control unit 8 (see FIG. 2 ) that controls the operation of the entire stacking device 1.

[0022] As will be described later, the first stacking position P1 is a section for placing the negative electrode plate Ea on the stacking table 2 by the first transfer unit 4. The second stacking position P2 is a section for placing the positive electrode plate Eb on the stacking table 2 by the second transfer unit 5.

[0023] The stacking table 2 holds the electrode plates E (negative electrode plates Ea and positive electrode plates Eb) to be stacked. The stacking table 2 includes a table main body 21 as a main body, and holding claws 22 that hold the electrode plates E placed on the table main body 21.

[0024] The table body 21 is a member having a rectangular shape in a plan view and a substantially horizontal upper surface 21a, and the upper surface 21a is provided with a plurality of through-holes (not shown). The table body 21 is also provided with a vacuum suction mechanism (not shown) that generates vacuum pressure through the plurality of through-holes.

[0025] As described below, when the separator S is supplied to the upper surface 21a of the table main body 21 by the separator supply unit 3, the table main body 21 adsorbs and holds the surface of the separator S that is in contact with the upper surface 21a by the negative pressure generated by the vacuum suction mechanism.

[0026] The upper surface 21a of the table body 21 may be made of any material having a plurality of through holes, such as a mesh steel plate or a porous metal (porous metal).

[0027] A horizontal movement mechanism (not shown) is provided on the table body 21. The horizontal movement mechanism moves the table body 21 back and forth horizontally in one direction (left and right direction) between the first stacking position P1 and the second stacking position P2.

[0028] Then, with the separator S held on the upper surface 21a, the table body 21 is moved back and forth by the horizontal movement mechanism, whereby the separator S is folded in a zigzag pattern.

[0029] Furthermore, a lifting mechanism (not shown) is provided on the table main body 21. The lifting mechanism lowers the table main body 21 at set predetermined pitches (more specifically, first and second lowering distances, which will be described later).

[0030] At the first stacking position P1, the table main body 21 is lowered by a predetermined pitch (first lowering distance) by the table-side lifting mechanism each time a negative electrode plate Ea is placed, and at the second stacking position P2, the table main body 21 is lowered by a predetermined pitch (second lowering distance) by the table-side lifting mechanism each time a positive electrode plate Eb is placed.

[0031] As shown in Fig. 3, the holding claws 22 include a pair of first claw members 22a and a pair of second claw members 22b provided above the table body 21. The pair of first claw members 22a press down from above to hold the negative electrode plate Ea placed on the table body 21 via the bellows-shaped separator S at the first stacking position P1 (see Fig. 1). The pair of second claw members 22b press down from above to hold the positive electrode plate Eb placed on the table body 21 via the bellows-shaped separator S at the second stacking position P2 (see Fig. 1).

[0032] Furthermore, the number of first claw members 22a and second claw members 22b does not need to be two (one pair) each, and any number can be used as long as it is possible to maintain the placement position of the electrode plate E placed on the table main body 21.

[0033] The first claw member 22a and the second claw member 22b are both made of rectangular flat plate-shaped members extending in one direction, and when viewed in a plane, are arranged with their longitudinal direction perpendicular to the direction of reciprocating movement of the table main body 21 (the direction of arrow A in Figure 3, which is the left-right direction in this embodiment) (the front-to-back direction in this embodiment).

[0034] The pair of first claw members 22a face each other in the orthogonal direction (front-rear direction) and are arranged, in a plan view, along the end of the negative electrode plate Ea placed on the table body 21 on the second stacking position P2 side (left side in this embodiment). The pair of first claw members 22a are provided with a horizontal movement mechanism (not shown), which allows the pair of first claw members 22a to move toward and away from each other along the orthogonal direction (front-rear direction). The pair of first claw members 22a are also provided with a lifting mechanism (not shown), which allows the pair of first claw members 22a to simultaneously move up and down (raise and lower) relative to the upper surface 21a of the table body 21.

[0035] The pair of first claw members 22 a are moved by the horizontal movement mechanism toward each other to a predetermined position (hereinafter referred to as the "first holding position"), and then moved downward (lowered) by the lifting mechanism, thereby abutting against both corners of the negative electrode plate Ea placed on the table main body 21 on the second stacking position P2 side (in this embodiment, the left side), thereby holding the negative electrode plate Ea in a placed position. The pair of first claw members 22 a are moved by the horizontal movement mechanism toward each other to a predetermined position (hereinafter referred to as the "first retracted position"), and then moved upward (raised) by the lifting mechanism, thereby releasing the holding state of the negative electrode plate Ea placed on the table main body 21 and retracting from the negative electrode plate Ea.

[0036] Meanwhile, the pair of second claw members 22b face each other in the orthogonal direction (front-rear direction) and are arranged, in a plan view, along the end of the positive electrode plate Eb placed on the table body 21 on the first stacking position P1 side (the right side in this embodiment). Similarly to the pair of first claw members 22a, the pair of second claw members 22b are also provided with a horizontal movement mechanism (not shown), which allows the pair of second claw members 22b to move toward and away from each other along the orthogonal direction (front-rear direction). Similarly to the pair of first claw members 22a, the pair of second claw members 22b are also provided with a lifting mechanism (not shown), which allows the pair of second claw members 22b to simultaneously move up and down (raise and lower) relative to the upper surface 21a of the table body 21.

[0037] The pair of second claw members 22b are moved by the horizontal movement mechanism toward each other to a predetermined position (hereinafter referred to as the "second holding position"), and then moved downward (lowered) by the lifting mechanism, thereby abutting against both corners of the positive electrode plate Eb placed on the table main body 21 on the first stacking position P1 side (in this embodiment, the right side), and thereby holding the placed posture of the positive electrode plate Eb. The pair of second claw members 22b are moved by the horizontal movement mechanism toward each other to a predetermined position (hereinafter referred to as the "second retracted position"), and then moved upward (raised) by the lifting mechanism, thereby releasing the hold of the positive electrode plate Eb placed on the table main body 21 and retracting from the positive electrode plate Eb.

[0038] As will be described later, the pair of first claw members 22a press down from above to hold the negative electrode plate Ea placed on the table main body 21 in the first stacking position P1, and then follow the movement of the table main body 21 to move to the second stacking position P2, where they release the held state of the negative electrode plate Ea. In other words, the pair of first claw members 22a are configured to be movable, following the upper surface of the negative electrode plate Ea immediately after it has been placed on the table main body 21, and are an example of a following means according to the present invention.

[0039] As will be described later, the pair of second claw members 22b press down from above to hold the placement posture of the positive electrode plate Eb placed on the table main body 21 at the second stacking position P2, and then follow the movement of the table main body 21 to move to the first stacking position P1, where they release the holding state of the positive electrode plate Eb. In other words, the pair of second claw members 22b are configured to be movable, following the upper surface of the positive electrode plate Eb immediately after it has been placed on the table main body 21, and are an example of a following means according to the present invention.

[0040] As described above, in the stacking device 1 of this embodiment, the following means is composed of a pair of first claw members 22 a and a pair of second claw members 22 b that press down from above to hold the placement posture of the electrode plate E placed on the stacking table 2 (more specifically, the table main body 21). That is, the stacking device 1 of this embodiment is configured to use the first claw members 22 a and the second claw members 22 b that are provided to follow the upper surface of the electrode plate E (negative electrode plate Ea or positive electrode plate Eb) immediately after it has been placed on the table main body 21 and to hold the placement position of the electrode plate E.

[0041] Therefore, the suitability judgment control described below can be realized at lower cost without the need to separately provide a device with a complex mechanism to follow the upper surface of the electrode plate E described above.

[0042] The separator supply unit 3 is an example of a separator supplying means according to the present invention. The separator supply unit 3 supplies a long strip of separator S to the upper surface 21a of the table body 21, and folds the separator S in a zigzag pattern by the reciprocating movement of the table body 21.

[0043] 1, the separator supply unit 3 has a pair of separator rollers 31. The pair of separator rollers 31 are arranged facing each other. The pair of separator rollers 31 are also arranged with their axial directions aligned horizontally and perpendicular to the above-mentioned direction (left-right direction).

[0044] A separator roll (not shown) consisting of a separator S wound into a roll is arranged above the pair of separator rollers 31, 31, and the end of the separator S pulled out from the separator roll passes between the pair of separator rollers 31, 31 from top to bottom, and is thereby clamped by the pair of separator rollers 31, 31.

[0045] The pair of separator rollers 31 , 31 rotate in a predetermined direction around their respective axes, whereby the separator S is fed downward and supplied to the upper surface 21 a of the table body 21 .

[0046] The pair of separator rollers 31 are provided with an elevating mechanism (not shown), which allows the pair of separator rollers 31 to move (raise and lower) between a predetermined upper position (hereinafter referred to as the "upper limit position H1") and a predetermined lower position (hereinafter referred to as the "lower limit position H2"). When the pair of separators 31 are positioned at the upper limit position H1, the stacking table 2, with the stacked negative electrode plates Ea, Ea... and positive electrode plates Eb, Eb... placed thereon, can move back and forth between the first stacking position P1 and the second stacking position P2 without interfering with the pair of separators 31. When the pair of separators 31 are positioned at the lower limit position H2, the separator S extending from the lower ends of the pair of separators 31 toward the table body 21 is in a substantially horizontal position.

[0047] The first transfer unit 4 is an example of a transfer means according to the present invention, and is configured to place the negative electrode plate Ea on the upper surface 21 of the table main body 2 at the first stacking position P1. Similarly to the first transfer unit 4, the second transfer unit 5 is also an example of a transfer means according to the present invention, and is configured to place the positive electrode plate Eb on the upper surface 21 of the table main body 2 at the second stacking position P2.

[0048] The first transfer unit 4 has, for example, a first suction unit 41 that can hold the negative electrode plate Ea by vacuum pressure, and a drive mechanism (not shown) that can move the first suction unit 41 horizontally and up and down (lift and lower). Similarly to the first transfer unit 4, the second transfer unit 5 also has, for example, a second suction unit 51 that can hold the positive electrode plate Eb by vacuum pressure, and a drive mechanism (not shown) that can move the second suction unit 51 horizontally and up and down (lift and lower).

[0049] At the first stacking position P1, there is disposed a first waiting table 11 on which the negative electrode plates Ea produced in the previous process are placed in advance after their positions have been adjusted, and the first transfer unit 4 holds the negative electrode plates Ea with a first suction unit 41 and transfers and places the negative electrode plates Ea from the first waiting table 11 onto the table main body 21. At the second stacking position P2, there is disposed a second waiting table 12 on which the positive electrode plates Eb produced in the previous process are placed in advance after their positions have been adjusted, and the second transfer unit 5 holds the positive electrode plates Eb with a second suction unit 51 and transfers and places the positive electrode plates Eb from the second waiting table 12 onto the table main body 21.

[0050] The configuration of the first transfer unit 4 and the second transfer unit 5 is not limited to this embodiment, and any configuration may be used as long as it is possible to transfer the electrode plate E between the first waiting table 11 or the second waiting table 12 and the table main body 21, such as a robot using a mechanism such as a rectangular coordinate type, a vertical multi-joint type, or a horizontal multi-joint type.

[0051] The first imaging unit 6 is an example of an imaging means according to the present invention, and acquires image data (hereinafter referred to as "first image data") of the table body 21 on which the negative electrode plate Ea is placed from above at the first stacking position P1. Similarly to the imaging unit 6, the second imaging unit 7 is also an example of an imaging means according to the present invention, and acquires image data (hereinafter referred to as "second image data") of the table body 21 on which the positive electrode plate Eb is placed from above at the second stacking position P2.

[0052] The first imaging unit 6 is, for example, a commercially available digital camera, and is disposed above the table body 21 at the first stacking position P1 with its imaging direction facing downward. Similarly to the first imaging unit, the second imaging unit 7 is, for example, a commercially available digital camera, and is disposed above the table body 21 at the second stacking position P2 with its imaging direction facing downward.

[0053] The first imaging unit 6 captures an overall image of the negative electrode plate Ea as first image data each time the table body 21 is placed on the table body 21 and thereafter moves downward (descends) by a predetermined first distance. The second imaging unit 7 captures an overall image of the positive electrode plate Eb as second image data each time the table body 21 is placed on the table body 21 and thereafter moves downward (descends) by a predetermined second distance.

[0054] Here, the first lowering distance is set in advance as a predetermined pitch when the table main body 21 is lowered at the first stacking position P1 immediately after the negative electrode plate Ea is placed thereon, and is set, for example, as the sum of the thickness of the negative electrode plate Ea and the thickness of the separator S. In other words, the first imaging unit 6 acquires a first image of the negative electrode plate Ea after the table main body 21 is lowered by the first lowering distance and the distance from the top surface of the negative electrode plate Ea is adjusted to a constant value.

[0055] The second lowering distance is set in advance as a predetermined pitch when the table main body 21 is lowered immediately after the positive electrode plate Eb is placed at the second stacking position P2, and is set, for example, as the sum of the thickness of the positive electrode plate Eb and the thickness of the separator S. In other words, the second imaging unit 7 acquires a second image of the positive electrode plate Eb after the table main body 21 is lowered by the second lowering distance and the distance from the top surface of the positive electrode plate Eb is adjusted to a constant value.

[0056] The first imaging unit 6 and the second imaging unit 7 may be provided with any imaging element such as a CCD image sensor or a CMOS image sensor.

[0057] The control unit 8 is an example of a control means according to the present invention. As described above, the control unit 8 controls the overall operation of the stacking device 1 and determines the appropriateness of the placement positions of the electrode plates E (negative electrode plate Ea and positive electrode plate Eb) based on the image data (first image data and second image data) acquired by the first imaging unit 6 and the second imaging unit 7.

[0058] As shown in FIG. 2, the control unit 8 includes an arithmetic processing unit 81 configured by a CPU (Central Processing Unit), and a memory unit 82 configured by a ROM (Read Only Memory), a RAM (Random Access Memory), an HDD (Hard Disk Drive), etc., and the memory unit 82 pre-stores, as will be described later, a program for executing the stacking operation of the electrode plates E by the stacking device 1, and a program for determining the appropriateness of the placement position of the electrode plates E placed on the table main body 21 when executing the stacking operation.

[0059] The control unit 8 may also be provided with an input means such as a touch panel, and an output means such as a monitor.

[0060] The control unit 8 controls the operation of the entire stacking device 1 in accordance with an operating procedure described later, thereby placing and stacking two types of electrode plates E, consisting of negative electrode plates Ea and positive electrode plates Eb, alternately arranged on the upper surface 21a of the table main body 21 with separators S interposed therebetween. The control unit 8 also executes suitability determination control described later, thereby determining the suitability of the placement position of the negative electrode plates Ea based on the first image data acquired by the first imaging unit 6, and determining the suitability of the placement position of the positive electrode plates Eb based on the second image data acquired by the second imaging unit 7.

[0061] [Operation Procedure of Stacking Device 1] Next, an operation procedure when two types of electrode plates E (negative electrode plates Ea and positive electrode plates Eb) are alternately stacked by the stacking device 1 will be described with reference to FIGS. 4 and 5. FIG.

[0062] First, as shown in Fig. 4A, in the stacking table 2, the table body 21 is stopped at the first stacking position P1 with the separator S held via the upper surface 21a. Note that the pair of first claw members 22a (only one first claw member 22a is shown because Fig. 4 is a front view) have been moved to the first retracted position and are stopped at a predetermined upper limit position h1a. Similarly, the pair of second claw members 22b (only one second claw member 22b is shown because Fig. 4 is a front view) have also been moved to the second retracted position and are stopped at a predetermined upper limit position h1b, similar to the first claw member 22a.

[0063] In the separator supply unit 3, the pair of separator rollers 31, 31 are stopped in their rotational motion and are stopped at the lower limit position H2.

[0064] Furthermore, in the first transfer unit 4 and the second transfer unit 5 (see FIG. 1), the first suction unit 41 and the second suction unit 51 are stopped at their respective predetermined standby positions. Note that the negative electrode plate Ea and the positive electrode plate Eb are placed on the first standby table 11 and the second standby table 12 (see FIG. 1), respectively, after their positions have been adjusted in advance.

[0065] When the stacking operation by the stacking device 1 is started, as shown in Figure 4B, the first transfer unit 4 moves the first suction unit 41 to hold the negative electrode plate Ea placed on the first waiting table 11, and then moves the negative electrode plate Ea above the table main body 21 and places the negative electrode plate Ea on the upper surface 21a of the table main body 21 via the separator S.

[0066] When the negative electrode plate Ea is placed on the upper surface 21a of the table body 21, the pair of first claw members 22a are moved horizontally toward the first holding position and then lowered toward a predetermined lower limit position h2a, whereby the pair of first claw members 22a come into contact with both corners of the negative electrode plate Ea on the second stacking position P2 side (left side), thereby maintaining the placement posture of the negative electrode plate Ea.

[0067] When the negative electrode plate Ea is held in place by the pair of first claw members 22a, the pair of separator rollers 31 are moved to the upper limit position H1 while feeding out the separator S, as shown in FIG. 4C.

[0068] Furthermore, the table body 21 is lowered by the first lowering distance, and is adjusted so that the distance between the upper surface of the negative electrode plate Ea and the first imaging unit 6 is approximately constant.

[0069] Then, the first imaging unit 6 captures an overall image of the negative electrode plate Ea from above to obtain first image data, converts the obtained first image data into an electrical signal, and transmits it to the control unit 8 (see Figure 2).

[0070] The control unit 8, which has received the electrical signal from the first imaging unit 6, executes a predetermined suitability determination control based on the first imaging data, and determines the suitability of the placement position of the negative electrode plate Ea placed on the table body 21. The specific content of the suitability determination control will be described later.

[0071] When the control unit 8 determines that the placement position of the negative electrode plate Ea is appropriate, the table body 21 moves to the second stacking position P2 while pulling out the separator S from the pair of separator rollers 31, 31, as shown in Fig. 5A. As a result, the separator S is folded by the pair of first claw members 22a, 22a into a zigzag fold.

[0072] On the other hand, if the control unit 8 determines that the placement position of the negative electrode plate Ea is inappropriate, the negative electrode plate Ea is discarded. Note that if the placement position of the negative electrode plate Ea is determined to be inappropriate after the stacking operation of the electrode plates E by the stacking device 1 has progressed to a certain extent, the negative electrode plate Ea is discarded together with the multiple electrode plates E, E, etc. that have already been stacked.

[0073] When the table body 21 reaches and stops at the second stacking position P2, the pair of separator rollers 31 are lowered to the lower limit position H2, as shown in Fig. 5B. As a result, the separator S extending from the lower ends of the pair of separators 31 toward the table body 21 is in a substantially horizontal position while covering the upper surfaces of the negative electrode plates Ea together with the pair of first claw members 22a.

[0074] When the pair of separator rollers 31, 31 reach the lower limit position H2 and stop, the second transfer unit 5 moves the second suction unit 51 to hold the positive electrode plate Eb placed on the second waiting table 12, and then moves the positive electrode plate Eb above the table main body 21 and places the positive electrode plate Eb on the upper surface of the negative electrode plate Ea via the separator S.

[0075] When the positive electrode plate Eb is placed on the upper surface of the negative electrode plate Ea, the pair of second claw members 22b are moved horizontally toward the second holding position and then lowered toward a predetermined lower limit position h2b, whereby the pair of second claw members 22b come into contact with both corners of the positive electrode plate Eb on the first stacking position P1 side (right side), thereby maintaining the placement posture of the positive electrode plate Eb.

[0076] When the placement position of the positive electrode plate Eb is maintained by the pair of second claw members 22b, the pair of separator rollers 31 are moved to the upper limit position H1 while feeding out the separator S, as shown in FIG. 5C.

[0077] Furthermore, the table body 21 is lowered by the second lowering distance, and is adjusted so that the distance between the upper surface of the positive electrode plate Eb and the second imaging unit 7 is approximately constant.

[0078] Thereafter, the second imaging unit 7 captures an image of the entire positive electrode plate Eb from above to obtain second image data, converts the obtained second image data into an electrical signal, and transmits it to the control unit 8.

[0079] The control unit 8, which has received the electrical signal from the second imaging unit 7, executes a predetermined suitability determination control based on the second imaging data, and determines the suitability of the placement position of the positive electrode plate Eb placed on the table body 21. The specific content of the suitability determination control will be described later.

[0080] The pair of first claw members 22a are moved horizontally toward the first retracted position and then moved upward and downward toward a predetermined upper limit position h1a, thereby releasing the pair of first claw members 22a from holding the negative electrode plate Ea located below the positive electrode plate Eb.

[0081] Then, when the control unit 8 determines that the placement position of the positive electrode plate Eb is appropriate, the table body 21 is moved again to the first stacking position P1 while pulling out the separator S from the pair of separator rollers 31. As a result, the separator S is folded by the pair of second claw members 22b into a zigzag fold.

[0082] On the other hand, if the control unit 8 determines that the placement position of the positive electrode plate Eb is inappropriate, the positive electrode plate Eb is discarded. Note that if the placement position of the positive electrode plate Eb is determined to be inappropriate after the stacking operation of the electrode plates E by the stacking device 1 has progressed to a certain extent, the positive electrode plate Eb is discarded together with the multiple electrode plates E, E, etc. that have already been stacked.

[0083] When the table body 21 reaches the first stacking position P1, the negative electrode plate Ea is placed again in accordance with the same procedure as that at the second stacking position P2 described above.

[0084] That is, the table body 21 reaches the first stacking position P1, and the separator S is folded and zigzag by the pair of second claw members 22b, 22b, and then the negative electrode plate Ea is again placed on the upper surface of the positive electrode plate Eb by the first moving part 4.

[0085] Then, the stacked position of the negative electrode plate Ea is maintained by a pair of first claw members 22a, 22a, and after the table main body 21 has descended by the first descending distance, the first imaging unit 6 again acquires the first image data, and based on the first image data, the control unit 8 determines the appropriate placement position of the negative electrode plate Ea.

[0086] In this way, the stacking operation at the first stacking position P1 and the second stacking position P2 is repeated alternately, so that the negative electrode plates Ea and the positive electrode plates Eb are stacked alternately in order with the separators S interposed therebetween.

[0087] [Control Method for Determining the Suitability of the Placing Position of the Electrode Plate E (Aptitude Determination Control)] Next, a control method for determining the suitability of the placing position of the electrode plate E (hereinafter referred to as "aptitude determination control" as appropriate), which is executed by the control unit 8, will be described with reference to Figures 6 and 7. Note that the above-mentioned suitability determination control is substantially the same regardless of the difference between the negative electrode plate Ea and the positive electrode plate Eb, and therefore the following description will mainly focus on the suitability determination control for the negative electrode plate Ea executed at the first stacking position P1, and will omit a description of the suitability determination control for the positive electrode plate Eb executed at the second stacking position P2.

[0088] The placement position of the negative electrode plate Ea placed on the upper surface 21a of the table main body 21 is determined by the position information of the four corners of the negative electrode plate Ea (a pair of corners Ag1 / Ag1 and a pair of corners Ag2 / Ag2 described later).

[0089] Here, when the negative electrode plate Ea is placed at the first stacking position P1, the pair of first claw members 22a immediately come into contact with each other to maintain the placement posture of the negative electrode plate Ea. Therefore, it is difficult to directly recognize the corners Ag1 at the end of the negative electrode plate Ea on the second stacking position P2 side (left side) on the first image data acquired by the first imaging unit 6 (see FIG. 1 ). Therefore, the control unit 8 checks the positions of the detection portions Cp near each of the first claw members 22a on the short and long sides of the negative electrode plate Ea on the first image data, and acquires positional information of each of the corners Ag1 from the positions of these detection portions Cp by performing a predetermined calculation process.

[0090] The negative electrode plate Ea is placed on the upper surface of the positive electrode plate Eb held by the pair of second claw members 22b, 22b, via the separator S. Therefore, the negative electrode plate Ea is placed in a state slightly tilted compared to a horizontal position, and although the corners Ag2, Ag2 on both sides of the end of the negative electrode plate Ea on the first stacking position P1 side (right side) can be directly recognized, accurate position information may not be obtained.

[0091] Therefore, in this embodiment, product dimension data for the negative electrode plate Ea is acquired in advance on the first waiting table 11 (see Figure 1), and positional information for the corners Ag2 and Ag2 on both sides of the negative electrode plate Ea at the end on the first stacking position P1 side (right side) is acquired using the product dimension data and the positional information for the corners Ag1 and Ag1 on both sides of the end on the second stacking position P2 side (left side) described above.

[0092] Based on the information on the placement position of the negative electrode plate Ea thus obtained (i.e., the position information of the pair of corners Ag1 / Ag1 and the position information of the pair of corners Ag2 / Ag2), the control unit 8 performs a comparison calculation with the pre-set tolerance range information for the placement position of the negative electrode plate Ea, and determines the appropriateness of the placement position of the negative electrode plate Ea.

[0093] Incidentally, the position of the upper surface of the electrode plate E (negative electrode plate Ea or positive electrode plate Eb) immediately after it is placed on the upper surface 21a of the table main body 21 is likely to vary to some extent due to factors such as manufacturing errors within the allowable range for each electrode plate E and air entrapment that occurs when folding the separator S. Here, the variations in the position of the upper surface of the electrode plate E may accumulate without canceling each other out as the number of stacked electrode plates E already placed on the table main body 21 increases. As a result, as described above, even if the table main body 21 is lowered by a predetermined lowering distance (first lowering distance or second lowering distance) each time each electrode plate E is placed on the table main body 21, it may be difficult to maintain a substantially constant position of the upper surface of the electrode plate E relative to the imaging unit (first imaging unit 6 or second imaging unit 7), and the appropriateness of the placement position of the electrode plate E may not be determined accurately.

[0094] Therefore, in the suitability judgment control of this embodiment, a predetermined compensation value (the first compensation value Cv1 or the second compensation value Cv2 described below) is calculated in advance according to the procedure shown below, and the compensation value is used to correct the acquired position information of the electrode plate E (negative electrode plate Ea or positive electrode plate Eb), and then the suitability of the placement position of the electrode plate E is judged.

[0095] 7, the control unit 8 receives from the first imaging unit 6 an electrical signal of first image data representing an overall image of the negative electrode plate Ea at the first stacking position P1 (see FIG. 1) (step S01). Then, based on the first image data, the control unit 8 acquires information about the placement position of the negative electrode plate Ea (position information about the pair of corners Ag1 and Ag1 and the pair of corners Ag2, hereinafter referred to as "first placement position information") (step S02). On the other hand, the control unit 8 also acquires information about the outer size of the pair of first claw members 22a, 22a that press down and hold the placement position of the negative electrode plate Ea from above (hereinafter referred to as "first outer size information") (step S03).

[0096] In step S03, the first outer size information may be appropriately selected, for example, the width dimension X (see FIG. 6) of each of the first claw members 22 a. The first outer size information may be obtained for either one of the first claw members 22 a, or may be obtained for both of the first claw members 22 a.

[0097] After acquiring the first external size information for the first claw member 22a, the control unit 8 reads information about the actual external size of the first claw member 22a (hereinafter referred to as "first actual external size information" as appropriate) that is pre-stored in the memory unit 82 (see Figure 2) into the calculation processing unit 81, performs a comparison calculation between the first actual external size information and the acquired first external size information, and calculates a correction value (hereinafter referred to as "first correction value Cv1" as appropriate) to match the first external size information to the first actual external size information (step S04).

[0098] Then, the control unit 8 uses the first correction value Cv1 to correct the first placement position information acquired in step S03 above to calculate the first post-adjustment placement position information (step S05), and determines the appropriateness of the placement position of the negative electrode plate Ea based on the first post-adjustment placement position information (step S06).

[0099] The above-described suitability determination control is also executed through similar steps (steps S01 to S06) when determining the suitability of the placement position of the positive electrode plate Eb at the second stacking position P2.

[0100] That is, based on the second image data, the control unit 8 acquires information on the placement position of the positive electrode plate Eb (the position information of the pair of corners Ag1 / Ag1 mentioned above and the position information of the pair of corners Ag2 / Ag2; hereinafter referred to as "second placement position information" as appropriate) (step S02), acquires information on the outer size of the pair of second claw members 22b / 22b (hereinafter referred to as "second outer size information" as appropriate) (step S03), and performs a comparison operation between the information on the actual outer size of the second claw members 22b (hereinafter referred to as "second actual outer size information" as appropriate) and the acquired second outer size information, thereby calculating a correction value (hereinafter referred to as "second correction value Cv2" as appropriate) for matching the second outer size information to the second actual outer size information (step S04).

[0101] Then, the control unit 8 uses the second correction value Cv2 to correct the second placement position information acquired in step S03 above to calculate second post-correction placement position information (step S05), and determines the appropriateness of the placement position of the positive electrode plate Eb based on the second post-correction placement position information (step S06).

[0102] As described above, the lamination device 1 in this embodiment is a lamination device that places and stacks a plurality of electrode plates (single plates) E, E... each consisting of two types of negative electrode plates Ea and positive electrode plates Eb, and includes a lamination table 2 that holds the electrode plates (single plates) E to be stacked, a first transfer unit (transfer means) 4 that places the negative electrode plates (single plates) Ea on the upper surface 21a of the lamination table 2 (more specifically, the table body 21), and a second transfer unit (transfer means) 5 that places the positive electrode plates (single plates) Eb on the upper surface 21a of the lamination table 2 (more specifically, the table body 21). The stacking device 1 is provided with a first imaging unit (imaging means) 6 that acquires, from above, first image data (image data) of the stacking table 2 on which the negative electrode plate (single plate) Ea is placed, each time the first transfer unit (transfer means) 4 places the negative electrode plate (single plate) Ea, and a second imaging unit (imaging means) 7 that acquires, from above, second image data (image data) of the stacking table 2 on which the positive electrode plate (single plate) Eb is placed, each time the second transfer unit (transfer means) 5 places the positive electrode plate (single plate) Eb. The stacking device 1 is also provided with a control device (control means) 8 that determines the appropriateness of the placement position of the negative electrode plate (single plate) Ea based on the first image data (image data), and that determines the appropriateness of the placement position of the positive electrode plate (single plate) Eb based on the second image data (image data).

[0103] Here, the stacking table 2 has a first claw member (following means) 22a that follows the upper surface of the negative electrode plate (single plate) Ea immediately after it has been placed on the stacking table 2, and a second claw member (following means) 22b that follows the upper surface of the positive electrode plate (single plate) Eb immediately after it has been placed on the stacking table 2.

[0104] Then, the control unit (control means) 8 acquires first outer size information (outer size information) of the first claw member (following means) 22a based on the first image data (image data), and then performs a comparison operation between the first outer size information (outer size information) and first actual outer size information (actual outer size information), which is the actual outer size of the first claw member (following means) 22a, and converts the first outer size information (outer size information) into the first actual outer size information (actual outer size information). A first correction value (correction value) Cv1 is calculated to match the negative electrode plate (single plate) Ea to the external size information, and first placement position information (placement position information) of the negative electrode plate (single plate) Ea is obtained based on the first image data (image data).The appropriateness of the placement position of the negative electrode plate (single plate) Ea is determined based on first post-adjustment placement position information (post-adjustment placement position information) obtained by correcting the first placement position information (placement position information) using the first correction value (adjustment value) Cv1.

[0105] Furthermore, the control unit (control means) 8 acquires second outer size information (outer size information) of the second claw member (following means) 22b based on the second image data (image data), and then performs a comparison operation between the second outer size information (outer size information) and second actual outer size information (actual outer size information), which is the actual outer size of the second claw member (following means) 22b, and calculates the second outer size information (outer size information) as the second actual outer size information (actual outer size information). A second correction value (correction value) Cv2 is calculated to match the positive electrode plate (single plate) Eb to the second image data (image data), and second placement position information (placement position information) of the positive electrode plate (single plate) Eb is obtained based on the second image data (image data), and the appropriateness of the placement position of the positive electrode plate (single plate) Eb is determined based on second post-adjustment placement position information (post-adjustment placement position information) obtained by correcting the second placement position information (placement position information) using the second correction value (adjustment value) Cv2.

[0106] In this way, the stacking device 1 in this embodiment is configured to use the first claw member 22a (or the second claw member 22b) that follows the upper surface of the negative electrode plate Ea (or the positive electrode plate Eb) to calculate the first correction value Cv1 (or the second correction value Cv2) to match the first outer size information (or the second outer size information) of the first claw member 22a (or the second claw member 22b) obtained based on the first image data (or the second image data) with the first actual outer size information (or the second actual outer size information). Furthermore, after calculating the first compensation value Cv1 (or the second compensation value Cv2), the first placement position information (or the second placement position information) of the negative electrode plate Ea (or the positive electrode plate Eb) acquired based on the first image data (second image data) is compensated using the first compensation value Cv1 (or the second compensation value Cv2), thereby acquiring first compensated placement position information (or second corrected placement position information). Then, based on the acquired first corrected placement position information (or second corrected position information), the appropriateness of the placement position of the first negative electrode plate Ea (or the positive electrode plate Eb) is determined.

[0107] Therefore, according to the stacking device 1 of this embodiment, in the negative electrode plate Ea (or the positive electrode plate Eb) placed on the stacking table 2, the image of the negative electrode plate Ea (or the positive electrode plate Eb) on the first image data (or the second image data) is enlarged or reduced due to variations in the position of the upper surface of the negative electrode plate Ea (or the positive electrode plate Eb), and the first placement position information (or the second placement position information) of the negative electrode plate Ea (or the positive electrode plate Eb) acquired based on the first image data (or the second image data) is Even if the first placement position information (or the second placement position information) contains an error resulting from a difference in scale, by correcting the first correction value Cv1 (or the second correction value Cv2) using the first correction value Cv1 (or the second correction value Cv2), it is possible to obtain first corrected placement position information (or the second corrected placement position information) that is at least close to the actual value, and the appropriateness of the placement position of the negative electrode plate Ea (or the positive electrode plate Eb) can be accurately determined using the first corrected placement position information (or the second corrected placement position information).

[0108] In the lamination device 1 of this embodiment, as described above, the plurality of single plates are made of two types of members, negative electrode plates Ea and positive electrode plates Eb, and are placed on the upper surface 21 a of the lamination table 2 (moving table 21) by a first transfer unit (transfer means) 4 and a second transfer unit (transfer means) 5 so that the negative electrode plates Ea and positive electrode plates Eb are alternately arranged with separators S interposed therebetween. Note that, as described above, the separators S are not limited to long strip-shaped separators and may be sheet-shaped separators.

[0109] By applying the stacking device of the present invention to an apparatus for manufacturing a stacked battery by alternately stacking two types of electrode plates (sheet plates) E consisting of negative electrode plates Ea and positive electrode plates Eb with separators S interposed therebetween, it is possible to accurately determine the appropriate placement positions of the negative electrode plates Ea and positive electrode plates Eb immediately after they are placed on the stacking table 2, and to manufacture a high-quality stacked battery.

[0110] Furthermore, in the stacking device 1 of this embodiment, the separator S is made of a long, strip-shaped member, and the stacking device 1 is further configured to be arranged above the stacking table 2 and to be further equipped with a separator supply unit (separator supply means) 3 that supplies the separator S to the upper surface 21a of the stacking table 2 (table main body 21) while moving back and forth horizontally and in one direction (left-right direction) relative to the stacking table 2.

[0111] Even in a stacking device such as this, which folds a long, strip-shaped separator S zigzag on a loading table 2 and alternately places and stacks a plurality of electrode plates (single plates) E, E... consisting of negative electrode plates Ea and positive electrode plates Eb so that they are each positioned between the folded portions of the separator S, the stacking device 1 of this embodiment can accurately determine the appropriate placement positions of the negative electrode plates Ea and positive electrode plates Eb immediately after they are placed on the stacking table 2.

[0112] In the above explanation, an example has been described in which the stacking table 2 and the separator supply unit (separator supply means) 3 are configured to be able to move back and forth horizontally relative to each other, and the separator supply unit 3 does not move but the stacking table 2 moves back and forth horizontally to fold the separator S in a zigzag pattern. However, this is not limited to this, and a configuration in which the stacking table 2 does not move and the separator supply unit 3 is configured to be able to move back and forth horizontally to perform the back and forth movement operation may also be used.

[0113] [Configuration of stacking device 1 in another embodiment] As another embodiment of the stacking device 1, predetermined compensation values ​​(first compensation value Cv1 and second compensation value Cv2) calculated when executing the above-mentioned suitability judgment control may be used to compensate for each of the predetermined pitches (first descent distance and second descent distance) that are pre-set for the downward movement of the table body 21.

[0114] Here, the timing for correcting the first lowering distance associated with the lowering operation of the table main body 21 on which the negative electrode plates Ea are placed, which is performed at the first stacking position P1, using the first compensation value Cv1 is not particularly limited. For example, the first lowering distance may be corrected using the first compensation value Cv1 every time a negative electrode plate Ea is placed on the table main body 21, or every time the number of negative electrode plates Ea already placed on the table main body 21 reaches a predetermined number. Furthermore, the timing for correcting the second lowering distance associated with the lowering operation of the table main body 21 on which the positive electrode plates Eb are placed, which is performed at the second stacking position P2, using the second compensation value Cv2 is not particularly limited. For example, the second lowering distance may be corrected using the second compensation value Cv2 every time a positive electrode plate Eb is placed on the table main body 21, or every time the number of positive electrode plates Eb already placed on the table main body 21 reaches a predetermined number.

[0115] Thus, in the stacking device 1 of another embodiment, the stacking table 2 (more specifically, the table main body 21) is controlled to descend a predetermined first descending distance (descending distance) each time a negative electrode plate (single plate) Ea is placed on the stacking table 2 at the first stacking position P1, and to descend a predetermined second descending distance (descending distance) each time a positive electrode plate (single plate) Eb is placed on the stacking table 2 at the second stacking position P2, and the control unit (control means) 8 is configured to compensate for the first descending distance using the above-mentioned first compensation value (correction value) Cv1, and to compensate for the second descending distance using the above-mentioned second compensation value (correction value) Cv2.

[0116] With this configuration, even if there is variation in the position of the upper surface of the negative electrode plate Ea placed on the stacking table 2, the stacking table 2 can be lowered to an appropriate position that corresponds to the variation by correcting the first lowering distance using the first compensation value Cv1, so that the position of the upper surface of the negative electrode plate Ea relative to the first imaging unit 6 can be more stably maintained at an approximately constant position. Furthermore, even if there is variation in the position of the upper surface of the positive electrode plate Eb placed on the stacking table 2, the stacking table 2 can be lowered to an appropriate position that corresponds to the variation by correcting the second lowering distance using the second compensation value Cv2, so that the position of the upper surface of the positive electrode plate Eb relative to the second imaging unit 7 can be more stably maintained at an approximately constant position.

[0117] Therefore, according to the stacking device 1 of the other embodiment, errors arising from differences in scale can be more reliably eliminated in the first placement position information (placement position information) of the negative electrode plate Ea acquired based on the first image data (image data), and the appropriateness of the placement position of the negative electrode plate Ea can be more accurately determined. Also, errors arising from differences in scale can be more reliably eliminated in the second placement position information (placement position information) of the positive electrode plate Eb acquired based on the second image data (image data), and the appropriateness of the placement position of the positive electrode plate Eb can be more accurately determined.

[0118] In actuality, the negative electrode plate Ea and the positive electrode plate Eb generally have slight warping or distortion within an allowable range, and therefore, the negative electrode plate Ea and the positive electrode plate Eb are placed on the upper surface 21a of the table body 21 in a state in which they have slight elasticity that allows them to deform in the vertical direction.

[0119] If the mounting positions of the negative electrode plate Ea and the positive electrode plate Eb placed in this state were to be held by a pair of first claw members 22a and a pair of second claw members 22b, respectively, there was a risk that the following problems would occur.

[0120] That is, the negative electrode plate Ea and the positive electrode plate Eb are held in the mounted position by a pair of first claw members 22a and a pair of second claw members 22b and 22b, respectively, which press down on their upper surfaces, and therefore there was a risk that the areas on each upper surface that come into contact with the pair of first claw members 22a and 22a and the pair of second claw members 22b and 22b would sink, leaving so-called "dents."

[0121] Furthermore, as described above, when the holding state of the negative electrode plate Ea and the positive electrode plate Eb by the pair of first claw members 22a and the pair of second claw members 22b and 22b is released, the pair of first claw members 22a and 22a and the pair of second claw members 22b and 22b are each configured to move horizontally toward the first open position and the second open position, respectively, and move away from the negative electrode plate Ea and the positive electrode plate Eb. Therefore, when the pair of first claw members 22a and the pair of second claw members 22b move away from the negative electrode plate Ea and the positive electrode plate Eb, respectively, the horizontal movement of the pair of first claw members 22a and the pair of second claw members 22b causes the negative electrode plate Ea and the positive electrode plate Eb to bulge due to the above-mentioned elasticity, and as a result, they rub against the pair of first claw members 22a and the pair of second claw members 22b, 22b, which could cause ``scratches'' on the upper surfaces of the negative electrode plate Ea and the positive electrode plate Eb.

[0122] In such a situation, according to the stacking device 1 of another embodiment, even if the negative electrode plates Ea and the positive electrode plates Eb are slightly warped or distorted as described above, the stacking table 2 can be lowered to an appropriate position that corresponds to the warp or distortion by compensating for the first lowering distance using the first compensation value Cv1 and the second lowering distance using the second compensation value Cv2, thereby maintaining the positions of the upper surfaces of the negative electrode plates Ea and the positive electrode plates Eb at a substantially constant position. Therefore, the operation of the pair of first claw members 22 a and the pair of second claw members 22 b can prevent dents or scratches from occurring on the upper surfaces of the negative electrode plates Ea and the positive electrode plates Eb, thereby improving the quality of the negative electrode plates Ea and the positive electrode plates Eb that are alternately placed and stacked on the upper surface 21 a of the stacking table 2 (table body 21).

[0123] In another embodiment of the stacking device 1, the control unit (control means) 8 may use the first compensation value Cv1 to compensate for the first lowering distance each time a negative electrode plate (single plate) Ea is placed on the stacking table 2 (more specifically, the table body 21) at the first stacking position P1, and may use the second compensation value Cv2 to compensate for the second lowering distance each time a positive electrode plate (single plate) Eb is placed on the stacking table 2 at the second stacking position P2. The specific timings for correcting the first lowering distance and the second lowering distance using the first compensation value Cv1 and the second compensation value Cv2 are preferably set during movement of the stacking table 2 between the first stacking position P1 and the second stacking position P2, which makes it possible to prevent an extension of the takt time when the stacking device 1 performs the stacking operation.

[0124] With this configuration, according to the lamination device 1 of another embodiment, even if there is variation in the position of the upper surface of the negative electrode plate Ea placed on the lamination table 2, it is possible to prevent the variation from accumulating each time the negative electrode plate Ea is placed on the lamination table 2, and it is possible to more accurately determine the appropriateness of the placement position of the negative electrode plate Ea. Furthermore, even if there is variation in the position of the upper surface of the positive electrode plate Eb placed on the lamination table 2, it is possible to prevent the variation from accumulating each time the positive electrode plate Eb is placed on the lamination table 2, and it is possible to more accurately determine the appropriateness of the placement position of the positive electrode plate Eb.

[0125] The above describes one embodiment of the present invention, but the present invention is not limited to such an embodiment, which is merely an example, and it goes without saying that the present invention can be embodied in various other forms without departing from the gist of the present invention. The scope of the present invention is indicated by the claims, and further includes the meaning of equivalents set forth in the claims, and all modifications within the scope of the claims.

[0126] Furthermore, in the above explanation, an example has been described in which the stacking table 2 and the separator supply means 3 are configured to be able to move back and forth horizontally relative to each other, and the separator supply means 3 does not move but the stacking table 2 moves back and forth horizontally to fold the separator in a zigzag pattern. However, this is not limited to this, and a configuration in which the stacking table 2 does not move and the separator supply means 3 is configured to be able to move back and forth horizontally to perform the back and forth movement operation may also be used.

[0127] The present invention can be used in a stacking device that places and stacks a plurality of sheets.

[0128] REFERENCE SIGNS LIST 1 Stacking device 2 Stacking table 21 Table body 21a Upper surface 22a First claw member (following means) 22b Second claw member (following means) 3 Separator supply unit (separator supply means) 4 First transfer unit (transfer means) 5 Second transfer unit (transfer means) 6 First imaging unit (imaging means) 7 Second imaging unit (imaging means) 8 Control unit (control means) Cv1 First compensation value (correction value) Cv2 Second compensation value (correction value) Ea Negative electrode plate (single plate) Eb Positive electrode plate (single plate) S Separator

Claims

1. A stacking device for placing and stacking a plurality of sheet metals, comprising: a stacking table for holding the sheet metal to be stacked; transfer means for placing the sheet metal on the top surface of the stacking table; imaging means for acquiring image data of the stacking table on which the sheet metal is placed from above each time the sheet metal is placed by the transfer means; and control means for determining the appropriateness of the placement position of the sheet metal based on the image data, wherein the stacking table has tracking means for following the top surface of the sheet metal immediately after it is placed on the stacking table, and the control means acquires external size information of the tracking means based on the image data, and then performs a comparison operation between the external size information and actual external size information which is the actual external size of the tracking means to calculate an adjustment value for matching the external size information with the actual external size information, and acquires placement position information of the sheet metal based on the image data, and determining whether the placement position of the sheet is appropriate based on compensated placement position information obtained by compensating the placement position information using the compensation value.

2. The stacking device according to claim 1, wherein the stacking table is lowered by a predetermined lowering distance each time a single plate is placed on the stacking table, and the control means compensates for the lowering distance using the compensation value.

3. The stacking device according to claim 2, wherein the control means adjusts the lowering distance each time a plate is placed on the stacking table.

4. A stacking device as set forth in any one of claims 1 to 3, characterized in that the following means is a claw member that presses down from above to maintain the placement position of the sheet placed on the stacking table.

5. A stacking device as claimed in any one of claims 1 to 3, characterized in that the plurality of sheets of plate are made of two types of members consisting of negative electrode plates and positive electrode plates, and are placed on the upper surface of the stacking table by the moving means so that the negative electrode plates and positive electrode plates are arranged alternately with separators interposed therebetween.

6. The stacking device according to claim 5, wherein the separator is made of a long strip-shaped member, and the stacking device further comprises separator supply means that is arranged above the stacking table and moves back and forth horizontally and in one direction relative to the stacking table to supply the separator to the upper surface of the stacking table.

Images