JP2020077583A - End effector, position acquisition method and work-piece stacking device - Google Patents

Abstract

To provide an end effector capable of acquiring an accurate position of a work-piece.SOLUTION: An end effector 200 which is attached to a transfer device 110 comprises: a base 210 of which movement is controlled in a vertical direction and a horizontal direction on the basis of operation of the transfer device 110; a pressing plate 220 which presses a work-piece that is a moving object of the transfer device 110, from a top face side of the work-piece; an elastic member 250 which connects the base 210 with the pressing plate 220 and is elastically deformed in the vertical direction when the pressing plate 220 presses the work-piece; an imaging apparatus 240 which is disposed so as to image a lower side at a position higher than the pressing plate 220 and images a predetermined range outside a peripheral edge 220a of the pressing plate 220; and an adsorption part 233 which holds the work-piece by adsorption when the pressing plate 220 presses the work-piece.SELECTED DRAWING: Figure 5

Description

  One aspect of the present invention relates to an end effector, a position acquisition method, and a work stacking apparatus.

  Conventionally, there is known a stacking device for alternately stacking a first electrode sandwiched between separators and a second electrode having a polarity different from that of the first electrode. In the stacking device disclosed in Patent Document 1, a first table on which a first electrode is mounted, a second table on which a second electrode is mounted, and a first electrode and a second electrode are stacked alternately. And a laminated table. In this stacking device, a first gripping part that grips the first electrode placed on the first table and a second gripping part that grips the second electrode placed on the second table are placed on the stacking table. The first electrodes and the second electrodes are alternately stacked.

JP, 2012-227130, A

  Generally, when transferring a work transferred on a transfer line from the transfer line to a mounting table, for example, a work whose position is specified by image recognition or the like is used by using an end effector provided on a transfer device such as a robot arm. May hold. For example, when the work is thin, the work may be warped on the transfer line. In this case, when the work is held by the end effector, the position of the work is specified based on the work in a warped state, so it is difficult to acquire the accurate position of the work when it is held by the end effector. There is a case.

  It is an object of one aspect of the present invention to provide an end effector, a position acquisition method, and a work stacking device that can acquire an accurate position of a work.

  An end effector according to one aspect of the present invention is an end effector attached to a transfer device, and includes a base whose movement is controlled in vertical and horizontal directions based on an operation of the transfer device, and transfer of the transfer device. A pressing part that presses the target work from the upper surface side of the work, an elastic member that connects the base and the pressing part, and elastically deforms in the vertical direction when the pressing part presses the work, and above the pressing part. The imaging device is arranged so as to image the lower side, and includes an imaging device that images a predetermined range outside the peripheral edge of the pressing unit, and a suction unit that holds the work by suction when the pressing unit presses the work.

  In the above-mentioned end effector, the image pickup device for acquiring the position of the work is arranged downward at the position above the pressing portion, and it is possible to image a predetermined range outside the peripheral edge of the pressing portion. Therefore, if the workpiece has an outer shape larger than that of the pressing portion, the peripheral edge of the workpiece pressed by the pressing portion can be imaged by the imaging device. In the state where the work is pressed by the pressing portion, the warp of the work is alleviated. Therefore, the position of the work can be accurately estimated based on the image of the work by the imaging device.

  The pressing portion may be lightened. With this configuration, it is possible to reduce the weight of the pressing portion.

  A through hole that vertically penetrates the pressing portion is formed in the pressing portion by lightening processing, and the suction portion may be inserted into the through hole. According to this structure, the suction portion can be easily brought into contact with the work surface pressed by the pressing portion.

  A method for acquiring a position of a work according to one aspect of the present invention includes a step of pressing a work from a top surface side of the work by a pressing portion, a step of imaging the work pressed by the pressing portion with an imaging device, and an image captured by the imaging device. Estimating the position of the workpiece with respect to the end effector based on the image of the workpiece.

  In the above position acquisition method, the work is imaged after the step of pressing the work. In the state where the work is pressed by the pressing portion, the warp of the work is alleviated, so that the position of the work can be specified more accurately using the imaging device.

  The peripheral edge of the pressing portion is smaller than the peripheral edge of the work over its entire circumference, and in the pressing step, the inside of the peripheral edge of the work is pressed by the pressing portion, and in the step of imaging, the portion of the work protruding from the pressing portion is pressed. You may image. With this configuration, the periphery of the pressed work can be easily imaged by the imaging device.

  The work is a flat plate having at least two linear parts that are in a positional relationship that intersects each other. In the process of estimating the position of the work, even if the intersection of the two linear parts is estimated as the position of the work. Good. Particularly, in the step of estimating the position of the work, image information obtained by removing the image of the predetermined area including the intersection from the image of the work may be acquired, and the intersection may be estimated based on the linear portion included in the image information. With this configuration, the original position of the intersection can be estimated even if the intersection of the linear portion of the workpiece is rolled up.

  A work stacking apparatus according to one aspect of the present invention transfers a transfer path on which a work is transferred, a stacking stage on which a work transferred on a transfer path is stacked, and a work transferred on a transfer path to a stacking stage. A transfer device, the transfer device includes an end effector, and the end effector is connected to the base for transfer control in a vertical direction and a horizontal direction based on the operation of the transfer device, An imaging unit that is arranged to capture an image of the pressing unit that presses the workpiece that is the transfer target of the device from the upper surface side of the workpiece, and the lower portion above the pressing unit, and captures at least a portion of the workpiece that is pressed by the pressing unit. The apparatus includes a device and a suction unit that holds the work by suction when the pressing unit presses the work.

  In the work stacking apparatus described above, since the warpage of the work is alleviated when the work is pressed by the pressing portion, the position of the work can be estimated more accurately using the imaging device. That is, in the transfer device, the work can be stacked on the stacking stage by reflecting the accurate position of the work held by the suction unit.

  A tracking camera is further provided, which is provided with a transfer path for transferring the work to the operation range of the transfer device, and the transfer path is provided with a tracking camera for imaging the transferred work and tracking the transfer position of the imaged work. May send the transfer position of the work to be tracked to the transfer device. According to this configuration, the work being conveyed can be transferred to the stacking stage.

  According to one aspect of the present invention, it is possible to provide a laminated body manufacturing apparatus in which the size of the apparatus is suppressed.

FIG. 3 is a cross-sectional view showing the inside of a power storage device. It is the II-II sectional view taken on the line of FIG. It is a schematic plan view which shows an electrode laminating apparatus. It is a block diagram showing a control system of an electrode lamination device. It is a side view which shows typically an end effector. It is a schematic diagram when a pressing plate is seen from the upper side. It is a figure which shows a mode that an electrode is hold | maintained by an end effector. It is a figure which shows the mode of the electrode conveyed by the conveyance path. 6 is a flow chart showing a method for acquiring the position of an electrode held by an end effector. FIG. 10 is a diagram schematically illustrating an example of an image captured by the image capturing device. It is a top view which shows the press plate by another example. It is a top view which shows the pressing plate by another example. It is a top view which shows the pressing plate by another example.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or equivalent elements will be denoted by the same reference symbols, without redundant description.

  First, a power storage device including a stack manufactured by the electrode stacking device according to the embodiment will be described. FIG. 1 is a cross-sectional view showing the inside of a power storage device. 2 is a sectional view taken along the line II-II of FIG. 1 and 2, the power storage device 1 is a lithium-ion secondary battery having a laminated electrode assembly.

  The power storage device 1 includes a case 2 having a substantially rectangular parallelepiped shape, for example, and an electrode assembly 3 housed in the case 2. The case 2 is made of metal such as aluminum. Although not shown, for example, a nonaqueous (organic solvent) electrolytic solution is injected into the case 2. On the case 2, the positive electrode terminal 4 and the negative electrode terminal 5 are arranged apart from each other. The positive electrode terminal 4 is fixed to the case 2 via an insulating ring 6, and the negative electrode terminal 5 is fixed to the case 2 via an insulating ring 7. Further, an insulating film is arranged between the electrode assembly 3 and the inner side surface and bottom surface of the case 2, and the case 2 and the electrode assembly 3 are insulated by the insulating film. Although a small gap is provided between the lower end of the electrode assembly 3 and the bottom surface of the case 2 in FIG. 1 for convenience, the lower end of the electrode assembly 3 is actually inside the case 2 with an insulating film interposed therebetween. Is touching the bottom of the.

  The electrode assembly 3 has a structure in which a plurality of positive electrodes 8 and a plurality of negative electrodes 9 are alternately stacked with a bag-shaped separator 10 interposed therebetween. The positive electrode 8 is wrapped in a bag-shaped separator 10. The positive electrode 8 wrapped in the bag-shaped separator 10 is configured as a positive electrode 11 with a separator. Therefore, the electrode assembly 3 has a structure in which the positive electrodes 11 with separators and the negative electrodes 9 are alternately stacked. The electrodes located at both ends of the electrode assembly 3 are the negative electrodes 9.

  The positive electrode 8 has a metal foil 14 which is a positive electrode current collector made of, for example, an aluminum foil, and a positive electrode active material layer 15 formed on both surfaces of the metal foil 14. The metal foil 14 has a foil main body 14a having a rectangular shape in a plan view and a tab 14b integrated with the foil main body 14a. The tab 14b projects from an edge near one end of the foil body 14a in the longitudinal direction. Then, the tab 14b penetrates the separator 10. The plurality of tabs 14b extending from the plurality of positive electrodes 8 are connected (welded) to the conductive member 12 in a foil-collected state, and are connected to the positive electrode terminal 4 via the conductive member 12. In FIG. 2, the tab 14b is omitted for convenience.

  The positive electrode active material layer 15 is formed on both front and back surfaces of the foil body 14a. The positive electrode active material layer 15 is a porous layer including a positive electrode active material and a binder. Examples of the positive electrode active material include complex oxides, metallic lithium, sulfur and the like. The composite oxide contains, for example, at least one of manganese, nickel, cobalt, and aluminum and lithium.

  The negative electrode 9 has a metal foil 16 which is a negative electrode current collector made of, for example, a copper foil, and a negative electrode active material layer 17 formed on both surfaces of the metal foil 16. The metal foil 16 has a foil main body 16a having a rectangular shape in plan view and a tab 16b integrated with the foil main body 16a. The tab 16b projects from an edge near one end of the foil body 16a in the longitudinal direction. The tab 16b is connected to the negative electrode terminal 5 via the conductive member 13. Note that the tab 16b is omitted in FIG. 2 for convenience.

  The negative electrode active material layer 17 is formed on both front and back surfaces of the foil body 16a. The negative electrode active material layer 17 is a porous layer formed containing a negative electrode active material and a binder. Examples of the negative electrode active material include graphite, highly oriented graphite, carbon such as mesocarbon microbeads, hard carbon and soft carbon, alkali metals such as lithium and sodium, metal compounds, SiOx (0.5 ≦ x ≦ 1.5). ) And other metal oxides or boron-added carbon.

  The separator 10 has a rectangular shape in plan view. Examples of the material for forming the separator 10 include a porous film made of a polyolefin resin such as polyethylene (PE) and polypropylene (PP), or a woven or non-woven fabric made of polypropylene, polyethylene terephthalate (PET), methyl cellulose and the like. ..

  When manufacturing the electricity storage device 1 configured as described above, first, the positive electrode 11 with a separator and the negative electrode 9 are first manufactured, and then the positive electrode 11 with a separator and the negative electrode 9 are alternately stacked to form the positive electrode 11 with a separator and the negative electrode 9 The electrode assembly 3 is obtained by fixing. Then, the tab 14b of the positive electrode 11 with a separator is connected to the positive electrode terminal 4 via the conductive member 12, and the tab 16b of the negative electrode 9 is connected to the negative electrode terminal 5 via the conductive member 13, and then the electrode assembly 3 is cased. Store in 2 For example, in the manufacturing process of the negative electrode 9, a strip-shaped electrode base material provided with an active material layer is manufactured, and the negative electrode 9 is manufactured by cutting the electrode base material. In the process of manufacturing the positive electrode 11 with a separator, a strip-shaped electrode base material provided with an active material layer is manufactured, and the positive electrode 8 is manufactured by cutting the electrode base material. An example of the cutting means is die cutting, for example. The positive electrode 11 with a separator is manufactured by wrapping the manufactured positive electrode 8 in a separator. Hereinafter, the positive electrode 11 with a separator and the negative electrode 9 may be simply referred to as electrodes.

  Next, the electrode stacking apparatus (work stacking apparatus) 100 according to the embodiment will be described with reference to FIG. FIG. 3 is a schematic plan view showing the electrode stacking device 100. As shown in FIG. 3, the electrode stacking device 100 includes a positive electrode carrier device 101, a negative electrode carrier device 103, a stacking stage 105, a positive electrode transfer device 110A, a negative electrode transfer device 110B, and a positive electrode tracking camera (tracking device). It has a camera) 120A and a negative tracking camera (tracking camera) 120B. In the electrode stacking apparatus 100, the positive electrode with separator (first electrode) 11 transferred by the positive electrode transfer apparatus 101 and the negative electrode (second electrode) 9 transferred by the negative electrode transfer apparatus 103 are alternately arranged on the plurality of stacking stages 105. Stacked. The electrode stacking device 100 includes a positive electrode transport device 101, a negative electrode transport device 103, a positive electrode transfer device 110A, a negative electrode transfer device 110B, a positive electrode tracking camera 120A, and a controller 150 connected to the negative electrode tracking camera 120B. (See Figure 4). The controller 150 may be, for example, a computer including a CPU, a memory and the like.

  The positive electrode carrying device 101 carries the positive electrode 11 with a separator manufactured in the previous step along a predetermined carrying path. In one example, the pre-process may be a separator packaging system 91 that manufactures a positive electrode 11 with a separator by wrapping the positive electrode 8 manufactured by die cutting the electrode base material with a separator. In the present embodiment, the separator packaging system 91 supplies the positive electrode 11 with a separator to the positive electrode carrier device 101 in a plurality of lines (two lines in the illustrated example). The positive electrode transfer device 101 is formed of, for example, a belt conveyor. The separator-attached positive electrode 11 is transported in two lines by the transport surface 101a of the belt conveyor that constitutes the transport path. As illustrated, the positive electrode transport device 101 is linearly arranged along the X direction starting from the separator packaging system 91. In the positive electrode transfer apparatus 101, for example, a rotary encoder is provided on the belt conveyor, and the transfer speed can be acquired by this rotary encoder. The acquired transport speed is transmitted to the controller 150, for example.

  The negative electrode carrying device 103 carries the negative electrode 9 manufactured in the previous step along a predetermined carrying path. The pre-process may be, for example, a die-cut system 93 that manufactures the negative electrode 9 by die-cutting the electrode base material. In the present embodiment, the die-cut system 93 supplies the negative electrode 9 to the negative electrode carrier device 103 in a plurality of lines (two lines in the illustrated example). The negative electrode transfer device 103 is formed of, for example, a belt conveyor. The negative electrode 9 is transferred in two lines by the transfer surface 103a of the belt conveyor that forms the transfer path. As illustrated, the negative electrode transport device 103 is linearly arranged along the X direction starting from the die cutting system 93. In the negative electrode transfer device 103, for example, a rotary encoder is provided on the belt conveyor, and the transfer speed can be acquired by this rotary encoder. The acquired transport speed is transmitted to the controller 150, for example.

  On the stacking stage 105, the separator-attached positive electrode 11 transported by the positive electrode transport device 101 and the negative electrode 9 transported by the negative electrode transport device 103 are stacked alternately. In this embodiment, at least one laminated stage 105 is arranged. In the illustrated example, a plurality of sets (four sets) of a pair of stacked stages 105 arranged adjacent to each other in the X direction are arranged. In the set of the pair of laminated stages 105, for example, the laminated body 22 is alternately formed on one laminated stage 105 and the other laminated stage 105. That is, the positive electrode 11 with a separator and the negative electrode 9 are alternately laminated on one of the lamination stages 105 to form a laminated body 22, and then the positive electrode 11 with a separator and the negative electrode 9 are laminated alternately on the other lamination stage 105. Body 22 is formed and the process is repeated. When the laminated body 22 is formed on the one laminated stage 105, the laminated body 22 of the one laminated stage 105 is carried out while the laminated body 22 is formed on the other laminated stage 105. The stacked body 22 may be carried out by a transport path provided below the stacking stage 105 in the Z direction. Further, the stacked body 22 may be carried out by a top-surface transport path that is provided above the stacking stage in the Z direction and is configured by, for example, an overhead traveling carriage. For example, in FIG. 3, the transport path or the top transport path is indicated by arrow 140.

  The positive electrode tracking camera 120A tracks the positive electrode which is being conveyed along the conveying path by the positive electrode conveying device 101. For example, a plurality of positive electrode tracking cameras 120A are arranged along the transport path of the positive electrode transport device 101. The number of positive electrode tracking cameras 120A may be the same as the number of rows of the positive electrodes 11 with separators conveyed by the positive electrode conveying device 101, for example. In this case, one positive electrode tracking camera 120A and the other positive electrode tracking camera 120A image the positive electrodes 11 with separators conveyed in different rows. In the illustrated example, two positive electrode tracking cameras 120A are arranged at positions separated from each other in the X direction. For example, one positive electrode tracking camera 120A is arranged at a position close to the base end of the positive electrode carrier device. The tracking camera 120A for the positive electrode images the positive electrode 11 with a separator that is transported in the right column (L1) in the transport direction D1. The other positive electrode tracking camera 120 </ b> A is arranged near the center of the positive electrode carrier 101. The tracking camera for positive electrode 120A images the positive electrode with a separator 11 that is transported in the left column (L2) facing the transport direction D1. At the image pickup position of the tracking camera 120A for the positive electrode, the lamination of the positive electrode 11 with the separator in the right column (L1) has already been completed. The image information captured by the positive electrode tracking camera 120A is transmitted to the controller 150. The controller 150 estimates the position of the positive electrode 11 with the separator being conveyed, based on the information from the positive electrode tracking camera 120A and the information on the conveying speed input from the positive electrode conveying device 101.

  The negative electrode tracking camera 120 </ b> B tracks the negative electrode 9 being transported on the transport path by the negative electrode transport device 103. For example, a plurality of negative electrode tracking cameras 120B are arranged along the transportation path of the negative electrode transportation device 103. The number of the negative electrode tracking cameras 120B may be the same as the number of rows of the negative electrodes 9 conveyed by the negative electrode conveying device 103, for example. In this case, one negative electrode tracking camera 120B and the other negative electrode tracking camera 120B image the negative electrodes 9 conveyed in different rows. In the illustrated example, the two negative tracking cameras 120B are arranged at positions separated from each other in the X direction. For example, one negative electrode tracking camera 120B is arranged at a position close to the base end of the negative electrode carrier device 103. The negative electrode tracking camera 120B images the negative electrode 9 transported in the right side column (L3) in the transport direction D2. The other negative electrode tracking camera 120B is arranged near the center of the negative electrode carrier device 103. The negative electrode tracking camera 120B images the negative electrode 9 conveyed in the left side column (L4) in the conveyance direction D2. At the image pickup position of the negative electrode tracking camera 120B, the lamination of the negative electrodes 9 in the right column (L3) has already been completed. The image information captured by the negative electrode tracking camera 120B is transmitted to the controller 150. In the controller 150, the position of the negative electrode 9 being conveyed is estimated based on the information from the negative electrode tracking camera 120B and the information on the conveying speed input from the negative electrode conveying device 103.

  The positive electrode transfer device 110 </ b> A transfers the separator-attached positive electrode 11, which is being transferred along the transfer path by the positive electrode transfer device 101, to the stacking stage 105. That is, the positive electrode transfer device 110 </ b> A moves while holding the positive electrode 11 with the separator being conveyed and places it on the stacking stage 105. The positive electrode transfer device 110A is arranged corresponding to a set of a pair of stacked stages 105. In the illustrated example, the positive electrode transfer device 110A is arranged adjacent to each set of the laminated stages 105. For example, the positive electrode transfer device 110A is arranged on the upstream side in the transport direction of the separator-attached positive electrode 11 with respect to the set of the stacking stage 105. The positive electrode transfer device 110A is a pick-and-place device having an end effector for holding the positive electrode 11 with a separator at the tip of an arm, and may be, for example, a horizontal articulated robot or a parallel link robot. The position information of the positive electrode 11 with the separator transported by the positive electrode transport device 101 is input to the positive electrode transfer device 110A from the controller 150. The positive electrode transfer device 110A specifies the transport position of the separator-attached positive electrode 11 based on the position information input from the controller 150. Thereby, the positive electrode transfer device 110A can hold the positive electrode 11 with the separator by the end effector.

  The negative electrode transfer device 110 </ b> B transfers the negative electrode 9 being transferred on the transfer path by the negative electrode transfer device 103 to the stacking stage 105. That is, the negative electrode transfer device 110 </ b> B moves while holding the negative electrode 9 being conveyed, and places it on the stacking stage 105. The negative electrode transfer device 110B is arranged corresponding to a set of a pair of stacked stages 105. In the illustrated example, the negative electrode transfer device 110B is arranged adjacent to each set of the laminated stages 105. For example, the negative electrode transfer device 110B is arranged on the upstream side in the transport direction of the negative electrode 9 with respect to the set of the stacking stage 105. The negative electrode transfer device 110B is a pick and place device having an end effector for holding the negative electrode 9 at the tip of an arm, and may be, for example, a horizontal articulated robot or a parallel link robot. The controller 150 inputs the positional information of the negative electrode 9 transported by the negative electrode transport device 103 to the negative electrode transfer device 110B. The negative electrode transfer device 110B identifies the transport position of the negative electrode 9 based on the position information input from the controller 150. Thereby, the negative electrode transfer device 110B can hold the negative electrode 9 by the end effector.

  Next, the end effector 200 included in the positive electrode transfer device 110A and the negative electrode transfer device 110B (collectively referred to as “transfer device 110”) will be further described. FIG. 5 is a side view schematically showing the end effector. The end effector 200 includes a base 210 connected to the tip of the arm 111 of the transfer device 110, a pressing plate (pressing portion) 220 attached to the base 210, a suction device 230, and an imaging device 240. In the following description, the separator-attached positive electrode 11 and negative electrode 9 held by the end effector 200 are collectively referred to as an electrode (work) 20.

  The base 210 can be connected to the arm 111 so that its relative position with respect to the tip of the arm 111 does not shift. As a result, the base 210 is controlled to move vertically and horizontally based on the operation of the transfer device 110. The shape of the base 210 is not particularly limited. As an example, as schematically shown in FIG. 5, the base 210 may include an upper base 211 and a lower base 215 formed at the lower end of the upper base 211. For example, the upper base 211 may have a cylindrical shape. The tip of the arm 111 is connected to the upper end of the upper base 211. The lower base 215 is connected (fixed) to the lower end of the upper base 211 so that the relative position with respect to the upper base 211 does not shift. The lower base 215 may have a flat plate shape having a larger area than that of the upper base 211 when viewed in the vertical direction.

  An adsorption device 230 is provided on the lower surface 215a of the lower base 215. As an example, the suction device 230 is a vacuum suction device and includes a vacuum cylinder 231 fixed to the lower surface 215a of the lower base 215 and a suction portion (suction nozzle) 233 connected to the lower end of the vacuum cylinder 231. .. A vacuum source such as a vacuum pump is connected to the vacuum cylinder 231. In the present embodiment, the plurality of suction devices 230 are connected to the lower base 215. In the illustrated example, four adsorption devices 230 are arranged so as to correspond to the four corners of the electrode 20, respectively.

  The pressing plate 220 is a portion that presses the electrode 20 that is the transfer target of the transfer device 110 from the upper surface side. FIG. 6 is a schematic view of the pressing plate as viewed from above. In the illustrated example, the electrode 20 and the pressing plate 220 arranged on the electrode 20 are shown. The electrode 20 has a substantially rectangular shape in a plan view. As an example, the four corner portions of the electrode 20 may be curved in an arc shape. Note that the tab of the electrode 20 is omitted in FIG.

  The pressing plate 220 has a substantially rectangular shape in a plan view. In a plan view, the four corner portions of the pressing plate 220 may be curved in an arc shape, for example. Further, in plan view, the peripheral edge 220a of the pressing plate 220 is smaller than the peripheral edge 20a of the electrode 20 over the entire circumference. That is, the interval W1 between the long sides of the pressing plate 220 and the interval W2 between the short sides of the electrode 20 are smaller than the interval W3 of the long sides and the interval W4 of the short sides of the electrode 20, respectively. For example, when the distance W4 between the short sides of the electrode 20 is about 150 mm and the distance W3 between the long sides is about 100 mm, the distance W2 between the short sides of the pressing plate 220 is about 145 mm, and the distance between the long sides is about 145 mm. The spacing W1 may be about 95 mm. That is, the peripheral edge 220a of the pressing plate 220 is located approximately 2.5 mm inside the peripheral edge 20a of the electrode 20.

  Note that, as shown in FIG. 6, when the electrode 20 is pressed by the pressing plate 220, the pressing plate 220 may slightly rotate with respect to the electrode 20 with the axis along the vertical direction as the center of rotation. .. Even in this case, since the peripheral edge 220a of the pressing plate 220 is smaller than the peripheral edge 20a of the electrode 20, the pressing plate 220 can be arranged inside the electrode 20. In FIG. 6, axes that extend in the long side direction and the short side direction are drawn on the pressing plate 220 so that it is easy to recognize that the pressing plate 220 is rotating. The pressing plate 220 is made of, for example, synthetic resin.

  The pressing plate 220 is connected to the lower base 215 via the elastic member 250. That is, the elastic member 250 connects the lower base 215 and the pressing plate 220. As an example, the elastic member 250 may be a coil spring. In the present embodiment, the pressing plate 220 is connected to the lower base 215 via the four elastic members 250. The four elastic members 250 are connected to the four corners of the pressing plate 220 in a plan view. As shown in FIG. 5, in one example, the suction device 230 penetrates the pressing plate 220. In the natural state, the lower surface 221 of the pressing plate 220 is located below the suction portion 233 of the suction device 230.

  The image pickup device 240 is arranged so as to pick up an image of the lower part at a position above the pressing plate 220. For example, the image pickup device may be a camera provided with an image pickup device such as a CMOS or a CCD. As an example, as shown in FIG. 5, the imaging device 240 is fixed to the upper base 211. In the illustrated example, the imaging device 240 is fixed to a support piece 213 that projects laterally from the upper base 211. The image pickup device 240 is arranged so as to pick up an image of a part of a predetermined range outside the peripheral edge 220a of the pressing plate 220. Further, in the illustrated example, the two imaging devices 240 are fixed to the upper base 211. The number of imaging devices 240 is not particularly limited, and may be one or three or more, for example. In this embodiment, the two imaging devices 240 are arranged so as to image two different areas. As shown in FIG. 6, the imaging region R by the imaging device 240 may be, for example, peripheral regions at both ends of one long side. Although the tab of the electrode 20 is omitted in FIG. 6, the imaging region R may be, for example, a peripheral region at both ends of the long side opposite to the long side where the tab is formed.

  FIG. 7 is a diagram showing how the electrodes are held by the end effector. As shown in FIG. 7, when the electrode 20 is held by the end effector 200, the pressing plate 220 presses the electrode 20 which is being transported along the transport path from its upper surface in accordance with the operation of the transfer device 110. In this case, when the pressing plate 220 presses the electrode 20, the elastic member 250 elastically deforms in the vertical direction, and the pressing plate 220 relatively moves so as to approach the lower base 215. Then, the electrode 20 is sucked and held by the suction portion 233 of the suction device 230 exposed from the lower surface 221 of the pressing plate 220.

  FIG. 8 shows how the electrodes are transported along the transport path. 8A and 8B are side views of the electrodes. 8C is a plan view of the electrode. As shown in FIGS. 8A and 8B, the thin plate-shaped electrode 20 may be transported along the transport path in a state of being curved upward or downward. For example, the base material fed from the original roll has a curl due to being stored in a roll shape. In this case, the electrode is likely to be warped even after the electrode is formed by die cutting the base material. As shown in FIG. 8C, the electrode 20 in the warped state has a smaller width in the direction in which the warp is formed (for example, the carrying direction) than the electrode 20 in the flattened state by being pressed. Is becoming In this case, the position of the intersection of the long side and the short side of the electrode 20 is displaced between the electrode 20 that is not pressed and warped and the electrode 20 that is pressed and flat. In addition, in FIG. 8C, the electrode 20 in a warped state is shown by a solid line, and the electrode 20 in a pressed state is shown by a broken line.

  Subsequently, a method of acquiring the position of the electrode by the end effector will be described. First, the operation of the electrode stacking device 100 will be described. In the electrode stacking apparatus 100, the positive electrode transport device 101 transports the positive electrode 11 with the separator from the upstream side to the downstream side in the transport direction D1. Further, the negative electrode transport device 103 transports the negative electrode 9 from upstream to downstream in the transport direction D2. The transport positions of the separator-attached positive electrode 11 and the negative electrode 9 are estimated by the controller 150 based on the image information from the positive electrode tracking camera 120A and the negative electrode tracking camera 120B and the speed information of the positive electrode transport device 101 and the negative electrode transport device 103. ..

  The transfer device 110 moves the end effector 200 to the estimated transport position of the electrode 20, and presses the electrode 20 being transported by the pressing plate 220. Then, the electrode 20 is held by the suction device 230, and the electrode 20 pressed by the pressing plate 220 is imaged by the imaging device 240.

  In the electrode stacking device 100, the position of the electrode 20 held by the suction device 230 is estimated based on the image information captured by the imaging device 240. The position of the electrode 20 may be the position of the electrode 20 relative to the end effector 200. In the present embodiment, the position of the electrode 20 is acquired by estimating the position of the intersection of the long side and the short side of the electrode 20. The transfer device 110 stacks the electrode 20 held by the end effector 200 at a predetermined position on the stacking stage 105 based on the estimated position of the electrode 20.

  FIG. 9 is a flowchart showing a method for acquiring the position of the electrode held by the end effector. In the present embodiment, as described above, the electrode 20 pressed by the pressing plate 220 is imaged by the imaging device 240 (step S1). The imaging device 240 images the imaging region R including the intersection of the long side and the short side of the electrode 20 that is pressed flat by the pressing plate 220. In one example, the two imaging devices 240 capture images of two different imaging regions R. FIG. 10 is a diagram schematically showing an example of an image captured by one of the image capturing devices 240. Although FIG. 8 shows an example in which the four corners of the electrode 20 are curved in an arc shape, in FIG. An example in which the portion C is formed at a right angle is shown.

  Then, the position of the intersection of the long side 20L and the short side 20S of the electrode 20 is calculated from the imaged image of the electrode 20. As an example, the long side 20L and the short side 20S may be extracted from the image, and the position where the long side 20L and the short side 20S are connected may be calculated as the intersection P1. However, in the case of the electrode 20 having a warp, as shown in FIG. 10, it is conceivable that the corner portion C that is not pressed by the pressing plate 220 is rolled up and the position of the intersection is displaced. In FIG. 10, the position of the corner C of the electrode 20 when the corner C is not rolled up is shown as an intersection P2.

  Therefore, in the present embodiment, the position of the intersection is calculated by a two-step process. That is, in the present embodiment, as the first-stage processing, after step S1, the long side 20L and the short side 20S are extracted from the acquired image of the electrode 20 by edge extraction or the like, and the long side 20L and the short side 20S are extracted. The position where and are connected is acquired as a temporary intersection P1 (step S2). In the second stage processing, a more accurate position of the intersection P2 is calculated based on the extracted position of the intersection P1. First, the region RP around the intersection P1 with the extracted intersection P1 as the center is excluded from the image (step S3). In the example of FIG. 10, a rectangular area centered on the intersection P1 is excluded from the image. This region PR is set so as to include a region of the electrode 20 that is expected to roll up. In the present embodiment, since the peripheral edge 220a of the pressing plate 220 is located inside the peripheral edge 20a of the electrode 20 by about 2.5 mm, the region to be rolled up is expected to be within a range of about 2.5 mm from the intersection. Therefore, as an example, a range of 5 mm square centering on the intersection P1 is excluded from the image.

  Then, the position of the intersection P2 is calculated based on the image information excluding the region PR (step S4). In this step, the long side 20L and the short side 20S are extracted from the image excluding the region PR, and the intersections of the approximate straight line of the long side 20L and the approximate straight line of the short side 20S are defined as the long side 20L and the short side 20S. The intersection point P2 is calculated as In the present embodiment, the position of the intersection P2 (corner C) at both ends of one long side 20L is calculated by the two imaging devices. Accordingly, for example, the relative position of the electrode 20 with respect to the pressing plate 220 can be specified in the X direction, the Y direction, and the rotation direction.

  In the electrode stacking device 100 described above, the electrode 20 is imaged by the imaging device 240 after the step of pressing the electrode 20 with the pressing plate 220. The imaging device 240 for acquiring the position of the electrode 20 is arranged facing downwards at a position above the pressing plate 220. Then, the imaging device 240 can image a predetermined range outside the peripheral edge 220a of the pressing plate 220. Therefore, if the electrode 20 has an outer shape larger than that of the pressing plate 220, the peripheral edge 20a of the electrode 20 pressed by the pressing plate 220 can be imaged. In the state where the electrode 20 is pressed by the pressing plate 220, since the warp of the electrode 20 is alleviated, the position of the electrode 20 can be specified more accurately. That is, in the transfer device 110, the electrode 20 can be stacked on the stacking stage 105 by reflecting the accurate position of the electrode 20 held by the suction device 230.

  Further, in the present embodiment, the peripheral edge 220a of the pressing plate 220 is formed to be smaller than the peripheral edge 20a of the electrode 20 over the entire circumference. Then, in step S1, the inside of the peripheral edge 20a of the electrode 20 is pressed by the pressing plate 220, and the electrode 20 protruding from the pressing plate 220 is imaged. With this configuration, the peripheral edge 20a of the electrode 20 in the pressed state can be easily imaged by the imaging device 240.

  Further, the electrode 20 is in the shape of a rectangular flat plate having a long side 20L and a short side 20S that intersect each other. When the corner portion C of the electrode 20 is curved in an arc shape, the extension line of the straight portion of the long side 20L and the extension line of the straight portion of the short side 20S intersect with each other to form the long side 20L. It is assumed that the short side 20S and the short side 20S cross each other. In this case, the intersection of the linear portions on the two sides can be specified as the position of the electrode 20. In particular, in the present embodiment, the image information excluding the predetermined region PR including the intersection is acquired from the image of the electrode 20, and the intersection is specified based on the linear portion included in the image information. With this configuration, even if the corner C of the electrode 20 is rolled up, the position of the intersection P2 when the electrode 20 is arranged flat can be calculated.

  Further, in the present embodiment, the transport position of the electrode 20 is transmitted to the transfer device 110 by the tracking cameras 120A and 120B. Therefore, the electrode 20 can be transferred to the stacking stage 105 without interrupting the transfer of the electrode 20 by the transfer device (the positive electrode transfer device 102, the negative electrode transfer device 103).

  Although the embodiment of the present invention has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment.

  11, 12, and 13 are schematic diagrams showing other examples of the pressing plate 220 in the end effector 200. In these examples, the pressing plate that has been subjected to the lightening process is shown. FIG. 11 is a plan view showing a pressing plate according to another example. The pressing plate 320 is formed with four through holes 322 penetrating in the vertical direction. The through holes 322 are, for example, cylindrical spaces, and are formed at the four corners of the rectangular pressing plate 320 in plan view. For example, the four adsorption devices 230 (see FIG. 5) may be arranged in the four through holes 322, respectively.

  FIG. 12A is a plan view showing a pressing plate according to still another example. 12B is a sectional view taken along line bb of FIG. 12A. The pressing plate 420 has two through holes 422 penetrating in the vertical direction. The through hole 422 has a substantially track shape in a plan view and extends in the long side direction of the electrode 20. The two through holes 422 are spaced apart from each other in the short side direction and arranged in parallel with each other. For example, the suction devices 230 may be arranged at both ends in the longitudinal direction within the through hole 422.

  FIG. 13A is a plan view showing a pressing plate according to still another example. 13B is a sectional view taken along line bb of FIG. 13A. The pressing plate 520 has two groove portions 522 formed downward from the upper surface 520a. The groove portion 522 has a substantially track shape in a plan view and extends in the long side direction of the electrode 20. The two groove portions 522 are separated from each other in the short side direction and arranged in parallel with each other. A through hole 523 is formed in the groove 522 so as to penetrate to the lower surface 520b. The through holes 523 may be formed at both ends of the groove 522 in the longitudinal direction. For example, the adsorption device 230 may be arranged in the through hole 523.

  Through-holes 322, 422 or groove portions 522 are formed in the pressing plates 320, 420, 520 by lightening. Accordingly, the weight of the pressing plates 320, 420, 520 can be reduced. For example, when the electrode 20 is held by the end effector 200, the electrode 20 held by the suction device 230 receives an excessive weight from the pressing plate. By reducing the weight of the pressing plate, the load on the electrode 20 is reduced, so that the electrode 20 is prevented from falling off from the adsorption device 230. Further, by inserting the adsorption device 230 into the through hole, the adsorption device 230 can be easily brought into contact with the surface of the electrode 20 pressed by the pressing plate.

  Further, although the end effector 200 in which the suction device 230 and the pressing plate 220 are separately provided has been described, the present invention is not limited to this. For example, the suction device and the pressing plate may be integrated with each other. For example, a plurality of suction holes may be formed on the lower surface of the pressing plate, and the suction holes may adsorb the electrodes.

  20 ... Electrode (work), 100 ... Electrode stacking device (work stacking device), 200 ... End effector, 210 ... Base, 220 ... Pressing plate (pressing part), 233 ... Adsorption part, 240 ... Imaging device, 250 ... Elastic member ..

Claims (9)

An end effector attached to a transfer device,
A base whose movement is controlled in the vertical and horizontal directions based on the operation of the transfer device,
A pressing portion that presses the work to be transferred by the transfer device from the upper surface side of the work,
An elastic member that connects the base and the pressing portion and that elastically deforms in the vertical direction when the pressing portion presses the work,
An imaging device that is arranged so as to capture an image of the lower side above the pressing portion, and that captures an image of a predetermined range outside the peripheral edge of the pressing portion,
An end effector, comprising: a suction unit that holds the work by suction when the pressing unit presses the work.   The end effector according to claim 1, wherein the pressing portion is lightened. In the pressing portion, a through hole that vertically penetrates the pressing portion is formed by the lightening process,
The end effector according to claim 2, wherein the suction portion is inserted into the through hole. A method for acquiring the position of a work using the end effector according to any one of claims 1 to 3,
Pressing the work by the pressing portion from the upper surface side of the work,
A step of capturing an image of the workpiece pressed by the pressing portion by the imaging device;
Estimating the position of the work with respect to the end effector based on the image of the work taken by the imaging device. The peripheral edge of the pressing portion is smaller than the peripheral edge of the work all around,
In the pressing step, the inside of the peripheral edge of the work is pressed by the pressing portion,
The position acquisition method according to claim 4, wherein in the step of capturing an image, an image of a portion of the workpiece protruding from the pressing portion is captured. The work has a flat plate shape having at least two linear portions that are in a positional relationship of intersecting with each other,
The position acquisition method according to claim 5, wherein in the step of estimating the position of the work, the intersection of the linear portions of the two sides is estimated as the position of the work.   In the step of estimating the position of the work, image information obtained by removing an image of a predetermined area including the intersection from the image of the work is obtained, and the intersection is calculated based on the linear portion included in the image information. The position acquisition method according to claim 6. A work laminating apparatus,
A transport path through which the work is transported,
A stacking stage on which the works transported on the transport path are stacked,
A transfer device for transferring the work transferred on the transfer path to the stacking stage,
The transfer device includes an end effector,
The end effector is
A base whose movement is controlled in the vertical and horizontal directions based on the operation of the transfer device,
A pressing unit that is connected to the base and presses the work to be transferred by the transfer device from the upper surface side of the work,
An imaging device that is arranged so as to image the lower part above the pressing part, and that images at least a part of the work pressed by the pressing part,
A work stacking device, comprising: a suction unit that holds the work by suction when the pressing unit presses the work. The transport path is provided with a tracking camera for capturing an image of the workpiece to be transported and for tracking the transport position of the imaged workpiece.
The work stacking apparatus according to claim 8, wherein the tracking camera transmits the transport position of the work to be tracked to the transfer device.

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