Patent Description:
As in-vehicle batteries, for example, laminate-type batteries have been developed. Such a battery has a structure in which a container contains a laminated electrode assembly, in which multiple positive electrode plates and multiple negative electrode plates are alternatively laminated with a separator in between, and an electrolyte. For example, patent literature <NUM> discloses manufacturing of a laminate-type battery in which individual pieces of electrodes and separators are sucked by a suction pad by vacuum suction, conveyed to a lamination stage, and layered on the stage. Such a conveyance method is not limited to electrode plates and separators but could also be employed to convey other workpieces. Patent literature <NUM> discloses a workpiece conveyance device according to the preamble of claim <NUM>.

In vacuum suction, it is necessary to connect the suction pad and the vacuum pump by vacuum pipes. It is also necessary to connect the vacuum pump and the driving power supply by wirings. In the case the vacuum pump and the driving power supply are provided outside to move the suction pad, therefore, the vacuum pipes and the wirings may be entangled if the conveyance distance of the electrode plate, etc. is long or the conveyance route is complicated (e.g., includes branches or junctions). Thus, installation of vacuum pipes and wirings has imposed restriction on the design flexibility of the workpiece conveyance device.

The present disclosure addresses the issue described above, and a purpose thereof is to provide a technology of increasing the design flexibility of a workpiece conveyance device.

According to the invention the workpiece conveyance device includes: a plurality of holding heads that include a holding part that holds a workpiece and a vacuum pump that generates a holding force in the holding part; and a conveyance track that conveys the plurality of holding heads. The vacuum pump includes a pump unit that connects with the holding part to suck a surrounding air (atmosphere) from the holding part or to discharge the surrounding air to the holding part, the vacuum pump further including a shaft part that is rotated to activate the pump unit. The shaft part includes a first magnet magnetized in an alternating N poles and S poles around a shaft. The conveyance track includes a second magnet extending in a conveyance direction of the holding head, the second magnet alternately generating a magnetic force from the N pole and a magnetic force from the S pole in the conveyance direction and being arranged to generate a magnetic force between the second magnet and the first magnet of the holding head conveyed. By alternately switching a magnetic pole of a portion in the second magnet applying a magnetic force to the first magnet, the shaft part is rotated, which causes the pump unit to generate a holding force by sucking or discharging the surrounding air.

Optional combinations of the aforementioned constituting elements, and implementations of the present disclosure in the form of methods, devices, systems, etc. may also be practiced as additional modes of the present disclosure.

According to the present disclosure, the design flexibility of a workpiece conveyance device is increased.

Hereinafter, the present disclosure will be described based on preferred embodiments with reference to the accompanying drawings. The embodiments are not intended to limit the scope of the present disclosure but exemplify the present disclosure. Not all of the features and the combinations thereof described in the embodiments are necessarily essential. Identical or like constituting elements, members, processes shown in the drawings are represented by identical symbols and a duplicate description will be omitted as appropriate. The scales and shapes shown in the figures are defined for convenience's sake to make the explanation easy and shall not be interpreted limitatively. Terms like "first", "second", etc. used in the specification and claims do not indicate an order or importance by any means unless specified otherwise and are used to distinguish a certain feature from the others. Those of the members that are not important in describing the embodiment are omitted from the drawings.

<FIG> is a perspective view of a workpiece conveyance device <NUM> according to embodiment <NUM>. <FIG> is a perspective view showing a part of the workpiece conveyance device <NUM> on an enlarged scale. In <FIG>, illustration of a cover plate <NUM> of a holding head <NUM> is omitted.

The workpiece conveyance device <NUM> includes multiple holding heads <NUM> and a conveyance track <NUM>. Each holding head <NUM> of this embodiment sucks and holds a workpiece W by a suction force generated by sucking a surrounding air. By way of one example, the workpiece W includes at least one of an electrode plate or a separator of a battery. The workpiece W of this embodiment is a laminated sheet <NUM> (unit laminated body) in which an electrode plate and a separator are laminated. The laminated sheet <NUM> is a unit constituting a laminated electrode body <NUM>. In other words, multiple unit laminated bodies <NUM> are laminated, and the laminated electrode body <NUM> is obtained accordingly. The workpiece W is not limited to a component constituting a battery such as the electrode plate, the separator, and the laminated sheet <NUM>.

The conveyance track <NUM> is a mechanism to convey the multiple holding heads <NUM>. Each holding head <NUM> travels on the conveyance track <NUM>, using the conveyance track <NUM> as a guide rail. The conveyance track <NUM> includes a publicly known conveyance mechanism for conveying each holding head <NUM>. The conveyance track <NUM> of this embodiment includes a publicly known linear conveyance mechanism by way of one example. More specifically, the conveyance track <NUM> includes a rail part <NUM> (stator) having built therein multiple coils (not shown) arranged in the direction of extension. Further, each holding head <NUM> (movable part) includes a conveyance magnet <NUM> at a position that faces the coil when the holding head <NUM> is hung from the rail part <NUM>. The conveyance magnet <NUM> is, for example, a permanent magnet.

By applying the magnetic flux generated by energizing each coil to the conveyance magnet <NUM>, a thrust force along the rail part <NUM> and a force attracting the holding head <NUM> toward the rail part <NUM> are generated in the holding head <NUM>. This causes the holding head <NUM> to travel along the rail part <NUM>. The holding head <NUM> includes a roller <NUM> slidably in contact with the rail part <NUM>, and the distance to the rail part <NUM> is maintained by the roller <NUM>. The linear conveyance mechanism is publicly known, and a further detailed description thereof is omitted. The conveyance track <NUM> may include a conveyance mechanism other than a linear conveyance mechanism such as a mechanism for hauling the holding head <NUM> by a chain, etc..

The conveyance track <NUM> of this embodiment branches into multiple tracks. Further, the conveyance track <NUM> includes a reception part <NUM> and a delivery part <NUM>. In the reception part <NUM>, the holding head <NUM> receives the laminated sheet <NUM> from a laminated sheet manufacturing device <NUM> (unit laminated body manufacturing device). Further, the holding head <NUM> discharges, in the delivery part <NUM>, the laminated sheet <NUM> to a laminating device <NUM>. The laminating device <NUM> is a device to manufacture the laminated electrode body <NUM> by laminating multiple unit laminated bodies <NUM>. Further, multiple delivery parts <NUM> are provided for one reception part <NUM>. <FIG> schematically shows the laminated sheet manufacturing device <NUM> and the laminating device <NUM>, and illustration of the structure is omitted in part. The structures of the devices need not be as illustrated.

By way of example, the conveyance track <NUM> has a loop structure elongated in a predetermined direction, and a part of the loop splits into two tracks extending in parallel. In other words, the conveyance track <NUM> includes a first track 4a and a second track 4b and a third track 4c that branch from one end of the first track 4a. The second track 4b and the third track 4c branching from the first track 4a meet the first track 4a at the other ends. In other words, a branch point 4d is provided at one end of the first track 4a, and a meeting point 4e is provided at the other end of the first track 4a. The reception part <NUM> is provided in the first track 4a. Two delivery parts <NUM> are provided in each of the second track 4b and the third track 4c. In each of the second track 4b and the third track 4c, the two delivery parts <NUM> are arranged in series. The embodiment is non-limiting as to the shape of the conveyance track <NUM>. The conveyance track <NUM> need not include the branch point 4d or the meeting point 4e or include two or more branch points 4d or meeting points 4e.

In the reception part <NUM>, the holding head <NUM> receives the laminated sheet <NUM> as a workpiece W from the laminated sheet manufacturing device <NUM> and travels on the first track 4a. The holding head <NUM> arriving at the branch point 4d leading to the second track 4b and the third track 4d is caused by a control device <NUM> to advance to either the second track 4b or the third track 4c. The control device <NUM> is configured to switch the destination of the holding head <NUM> by controlling energization of the coil built in the rail part <NUM>. The control device <NUM> may be implemented by an element such as a CPU or memory of a computer or by a circuit as a hardware configuration, and by a computer program or the like as a software configuration. <FIG> illustrates a functional block implemented by cooperation of such components. It will be naturally understood by those skilled in the art that the functional block may be implemented in a variety of forms by combinations of hardware and software.

The holding head <NUM> advancing on the second track 4b or the third track 4c delivers the laminated sheet <NUM> to the laminating device <NUM> in the delivery part <NUM>. The holding head <NUM> discharging the laminated sheet <NUM> advances further on the second track 4b or the third track 4c, returns from the meeting point 4e to the first track 4a, and reaches the reception part <NUM> again. The holding head <NUM> receives the laminated sheet <NUM> in the reception part <NUM> and is conveyed to the delivery part <NUM>.

By way of one example, the laminated sheet manufacturing device <NUM> is a continuous drum-type manufacturing device in which multiple drums are combined. The processes of cutting, heating, bonding, laminating, and the like of electrode bodies and separators are performed in the drums. This enables high-speed and continuous manufacturing of the laminated sheet <NUM>. In the laminated sheet manufacturing device <NUM>, multiple individual pieces of first electrode plates <NUM> are obtained by a first electrode cutting drum 100a. Further, multiple individual pieces of second electrode plates <NUM> are obtained by a second electrode cutting drum 100b.

The first electrode plate <NUM> and the second electrode plate <NUM> are preheated and supplied to an adhesion drum 100c. Further, a continuous sheet (continuous body) of a first separator <NUM> and a continuous sheet of a second separator <NUM> are supplied to the adhesion drum 100c. The continuous sheet of the first separator <NUM>, the multiple first electrode plates <NUM>, the continuous sheet of the second separator <NUM>, and the multiple second electrode plates <NUM> are laminated and pressurized in this order to form a continuous laminated body in which multiple unit laminated bodies <NUM> are continuously arranged. The continuous laminated body is cut by a separator cutting drum 100d into multiple individual pieces of the laminated sheet <NUM>. The individual pieces of the laminated sheet <NUM> are conveyed to the reception part <NUM> and delivered to the holding head <NUM>.

The laminated sheet <NUM> is delivered from the holding head <NUM> to the laminating device <NUM> in the delivery part <NUM>. The laminating device <NUM> includes a laminating drum 200a. The laminating drum 200a sequentially conveys the multiple unit laminated bodies <NUM> received from the holding head <NUM> to the lamination stage 200b and discharges the unit laminated bodies <NUM> to the lamination stage 200b. This causes the unit laminated bodies <NUM> to be layered on the lamination stage 200b, and the laminated electrode body <NUM> is obtained accordingly. The laminated electrode body <NUM> thus formed is retrieved from the lamination stage 200b to be forward to the device for the next step. The laminated sheet <NUM> may be directly delivered from the holding head <NUM> to the laminating drum 200a, or a relay drum may be disposed between the holding head <NUM> and the laminating drum 200a.

Moreover, the conveyance track <NUM> includes a second magnet <NUM> extending in a conveyance direction D1 of the holding head <NUM>. The second magnet <NUM> extends in a range in the conveyance track <NUM> in which the holding head <NUM> carrying the workpiece W travels. Further, the second magnet <NUM> is provided to in proximity to the holding head <NUM> traveling on the conveyance track <NUM>. The structure and working of the second magnet <NUM> will be described in detail later.

<FIG> is a perspective view of the holding head <NUM> viewed from diagonally above. <FIG> is a perspective view of the holding head viewed from diagonally below. <FIG> is a perspective view of a vacuum pump <NUM>, and <FIG> is a perspective view of the cross section of the vacuum pump <NUM>. The holding head <NUM> includes a pad part <NUM>, a vacuum pump <NUM>, a holding cancellation valve <NUM>, a support part <NUM>, a conveyance magnet <NUM>, and a roller <NUM>. The support part <NUM> extends in a predetermined direction (e.g., the vertical direction). The pad part <NUM> is fixed to one end of the support part <NUM>, and the vacuum pump <NUM> is fixed to the other end. The holding cancellation valve <NUM>, the conveyance magnet <NUM>, and the roller <NUM> are fixed between the pad part <NUM> and the vacuum pump <NUM> in the support part <NUM>.

The pad part <NUM> has a shape of a flat plate elongated in a perpendicular direction D2 perpendicular to the conveyance direction D1 of the holding head <NUM>. The pad part <NUM> is oriented such that one principal surface thereof faces the laminated sheet manufacturing device <NUM> in the reception part <NUM> and faces the laminating device <NUM> in the delivery part <NUM>. The one principal surface constitutes a holding part <NUM> for holding the workpiece. The holding part <NUM> of this embodiment is comprised of a suction surface that sucks the workpiece W. The holding part <NUM> includes multiple suction holes <NUM>. The multiple suction holes <NUM> are distributed in the planar direction of the holding part <NUM>.

The multiple suction holes <NUM> are organized into four groups including a first suction hole group 30a, a second suction hole group 30b, a third suction hole group 30c, and a fourth suction hole group 30d. In each suction hole group, the suction holes <NUM> are arranged at predetermined intervals in the perpendicular direction D2. A first suction hole group 30a, a second suction hole group 30b, a third suction hole group 30c, and a fourth suction hole group 30d are arranged in the stated order, starting at the front side (downstream side) of the conveyance direction D1 of the holding head <NUM>. In each suction hole group, the suction holes <NUM> are connected to each other by a connecting pipe (not shown) extending in the perpendicular direction D2. The connecting pipe is connected to the vacuum pump <NUM> via a vacuum pipe <NUM> described later. A cover plate <NUM> is provided on the principal surface of the pad part <NUM> opposite to the holding part <NUM>.

The vacuum pump <NUM> is a device configured to generate a holding force in the holding part <NUM>. The vacuum pump <NUM> includes a pump unit <NUM>, a shaft part <NUM>, and a vacuum pipe <NUM>. The vacuum pump <NUM> of this embodiment is comprised of a publicly known diaphragm pump by way of one example. The embodiment is non-limiting as to the structure of the vacuum pump <NUM> so long as it can generate a holding force in the holding part <NUM> as the shaft part <NUM> is rotated.

The vacuum pump <NUM> of this embodiment includes multiple pump units <NUM>. By way of one example, the vacuum pump <NUM> includes four pump units <NUM>. Each pump unit <NUM> includes a pump chamber <NUM>, a diaphragm drive shaft <NUM>, an air inlet <NUM>, and an air outlet <NUM>. The air inlet <NUM> and the air outlet <NUM> are connected to the pump chamber <NUM> to establish communication between the spaces inside and outside the pump chamber <NUM>. Further, the pump chamber <NUM> includes a diaphragm (not shown), and the diaphragm drive shaft <NUM> is connected to the diaphragm. The diaphragm drive shaft <NUM> is connected to the shaft part <NUM>.

The shaft part <NUM> is rotated to activate the pump unit <NUM> by causing the diaphragm drive shaft <NUM> to make a reciprocal movement. The shaft part <NUM> is a so-called crankshaft. The reciprocal movement of the diaphragm drive shaft <NUM> elastically deforms the diaphragm, which causes the surrounding air outside the pump chamber <NUM> to be sucked from the air inlet <NUM> into the space inside the pump chamber <NUM> and causes the surrounding air inside the pump chamber <NUM> to be discharged from the air outlet <NUM> to the space outside the pump chamber <NUM>.

Each pump unit <NUM> communicates with the holding part <NUM> by way of the vacuum pipe <NUM> and sucks the surrounding air from each suction hole <NUM> of the holding part <NUM>. More specifically, one end of the vacuum pipe <NUM> is connected to the air inlet <NUM>. Further, the other end of the vacuum pipe <NUM> is connected to the connecting pipe of the pad part <NUM>. Thus, when each pump unit <NUM> is activated by the rotation of the shaft part <NUM>, the surrounding air is sucked from the suction hole <NUM> to generate a suction force, i.e., a holding force, in the holding part <NUM>. The diaphragm drive shafts <NUM> of the pump units <NUM> are coupled to the same shaft part <NUM>. Therefore, the pump units <NUM> generate a holding force by the rotation of the common shaft part <NUM>.

The holding head <NUM> holds one workpiece W by means of at least two pump units <NUM>. Further, the holding head <NUM> holds multiple workpieces W. By way of one example, the two of the four pump units <NUM> hold one workpiece W, and the other two pump units <NUM> hold another workpiece W.

More specifically, the four pump units <NUM> and the first suction hole group 30a-the fourth suction hole group 30d are associated one to one, and the suction hole groups are connected to the different pump units <NUM> via the vacuum pipe <NUM>. Hereinafter, the pump unit <NUM> and the vacuum pipe <NUM> connected to the first suction hole group 30a will be referred to as a first pump unit 34a and a first vacuum pipe 38a. Further, the pump unit <NUM> and the vacuum pipe <NUM> connected to the second suction hole group 30b will be referred to as a second pump unit 34b and a second vacuum pipe 38b. Further, the pump unit <NUM> and the vacuum pipe <NUM> connected to the third suction hole group 30c will be referred to as a third pump unit 34c and a third vacuum pipe 38c. Further, the pump unit <NUM> and the vacuum pipe <NUM> connected to the fourth suction hole group 30d will be referred to as a fourth pump unit 34d and a fourth vacuum pipe 38d.

The two workpieces W held by the respective holding heads <NUM> are arranged in the conveyance direction D1 of the holding heads <NUM>. The workpiece W located in front in the conveyance direction D1 is sucked by the first suction hole group 30a and the second suction hole group 30b. The workpiece W located behind in the conveyance direction D1 is sucked by the third suction hole group 30c and the fourth suction hole group 30d. Hereafter, the workpiece W located in front will be referred to as a front workpiece W1, and the workpiece W located behind will be referred to as a rear workpiece W2 for convenience.

The shaft part <NUM> is provided with a first magnet <NUM>. The first magnet <NUM> has a disc shape and are magnetized to result in N poles and S poles alternating around the shaft. The first magnet <NUM> is, for example, a permanent magnet. The shaft part <NUM> is configured to be rotated by a magnetic force generated between the second magnet <NUM> provided in the conveyance track <NUM> and the first magnet <NUM>.

<FIG> shows a mechanism to rotate the shaft part <NUM>. As shown in <FIG>, the second magnet <NUM> is arranged in proximity to the holding head <NUM> to generate a magnetic force between the second magnet <NUM> and the first magnet <NUM> of the holding head <NUM> conveyed. Further, the second magnet <NUM> is configured to alternately generate a magnetic force from the N pole and a magnetic force from the S pole in the conveyance direction D1 of the holding head <NUM>. The second magnet <NUM> of this embodiment is magnetized to result in N poles and S poles alternating in the conveyance direction D1 of the holding head <NUM>. The second magnet <NUM> is, for example, a permanent magnet. Thus, the magnetic pole of the portion in the second magnet <NUM> applying a magnetic force to the first magnet <NUM> (e.g., the portion in the second magnet <NUM> closest to the first magnet <NUM>) is alternately switched as the holding head <NUM> is conveyed. This generates a torque in the shaft part <NUM>, causing the first pump unit 34a-the fourth pump unit 34d to suck the surrounding air via the holding part <NUM> to generate a holding force in the holding part <NUM>.

Further, the second magnet <NUM> of this embodiment is configured such that N poles and S poles are spirally formed around the rotation axis Ax extending in the conveyance direction D1 of the holding head <NUM>. Further, the second magnet <NUM> is rotated around the rotation axis Ax. The rotation of the second magnet <NUM> is realized by, for example, causing the control device <NUM> to control the motor (not shown) connected to the second magnet <NUM>. By rotating the second magnet <NUM> having N poles and S poles spirally formed thereon, the magnetic pole of the portion in the second magnet <NUM> applying a magnetic force to the first magnet <NUM> is alternately switched even when the holding head <NUM> is at a rest. It is therefore possible to maintain the rotation of the shaft part <NUM> and continue to generate the holding force in the holding part <NUM> even while the holding head <NUM> is at rest.

The rotating speed of the second magnet <NUM> and the conveyance speed of the holding head <NUM> are adjusted so as not to fix the magnetic pole of the portion where a magnetic force is generated between the second magnet <NUM> and the first magnet <NUM>. Further, the arrangement of the N poles and the S poles in the respective magnets and the relative positions of the magnets necessary to rotate the shaft part <NUM> can be set as appropriate based on an experiment, simulation, etc. by the designer. Further, the second magnet <NUM> shown in <FIG> is non-contiguous in part in the range from the reception part <NUM> to the delivery part <NUM>. In this case, the length of a region in which the second magnet <NUM> is non-existent is set in accordance with the time elapsed since the shaft part <NUM> stops being rotated until the holding force (suction force) of the holding part <NUM> is lost and with the conveyance speed of the holding head <NUM>.

The holding cancellation valve <NUM> is a valve for canceling the holding force of the holding part <NUM>. <FIG> is a perspective view showing a part of the holding head <NUM> including the holding cancellation valve <NUM> on an enlarged scale. <FIG> are perspective views showing a part of the conveyance track <NUM> including the delivery part <NUM> on an enlarged scale. <FIG> shows the opening and closing action of the holding cancellation valve <NUM>. In <FIG>, illustration of the laminating device <NUM> is omitted.

As shown in <FIG>, the holding cancellation valve <NUM> is comprised of, for example, a plate spring and is fixed to a base plate <NUM> elongated in the conveyance direction D1. The base plate <NUM> is fixed to the support part <NUM> between the vacuum pump <NUM> and the pad part <NUM>. The vacuum pipe <NUM> is provided to extend through the base plate <NUM>. A branch pipe <NUM> joined to the vacuum pipe <NUM> is provided inside the base plate <NUM>. One end of the branch pipe <NUM> is joined to the vacuum pipe <NUM> and the other end opens to the space outside the base plate <NUM>. In this embodiment, the branch pipe <NUM> is joined to each of the first vacuum pipe 38a-the fourth vacuum pipe 38d. Hereafter, the branch pipe <NUM> joined to the first vacuum pipe 38a is referred to as a first branch pipe 52a, the branch pipe joined to the second vacuum pipe 38b is referred to as a second branch pipe 52b, the branch pipe <NUM> joined to the third vacuum pipe 58c is referred to as a third branch pipe 52c, and the branch pipe <NUM> joined to the fourth vacuum pipe 58d is referred to as a fourth branch pipe 52d.

In further accordance with this embodiment, two open ends of the branch pipes <NUM> are arranged on either side of the base plate <NUM> in the perpendicular direction D2. Further, the two open ends are arranged in the conveyance direction D1 on either side of the base plate <NUM>. The open end of the first branch pipe 52a is provided in front in the conveyance direction D1 on one side of the base plate <NUM>. The open end of the third branch pipe 52c is provided behind in the conveyance direction D1 on one side of the base plate <NUM>. The open end of the second branch pipe 52b is provided in front in the conveyance direction D1 on the other side of the base plate <NUM>. The open end of the fourth branch pipe 52d is provided behind in the conveyance direction D1 on the other side of the base plate <NUM>.

The open end of each branch pipe <NUM> is blocked by the holding cancellation valve <NUM>. In this embodiment, one plate spring elongated in the conveyance direction D1 is fixed one each to either side of the base plate <NUM> in the perpendicular direction D2. The ends of each plate spring block the open ends of the branch pipe <NUM> respectively and function as the holding cancellation valve <NUM>. By switching between a state in which each holding cancellation valve <NUM> is closed (a state in which the open end of the branch pipe <NUM> is blocked) and a state in which each holding cancellation valve <NUM> is open (a state in which the open end of the branch pipe <NUM> communicates with the surrounding air), it is possible to hold or discharge the workpiece W. Hereinafter, the holding cancellation valve <NUM> blocking the open end of the first branch pipe 52a is referred to as a first holding cancellation valve 24a, the holding cancellation valve <NUM> blocking the open end of the second branch pipe 52b is referred to as a second holding cancellation valve 24b, the holding cancellation valve <NUM> blocking the open end of the third branch pipe 52c is referred to as a third holding cancellation valve 24c, and the holding cancellation valve <NUM> blocking the open end of the fourth branch pipe 52d is referred to as a fourth holding cancellation valve 24d.

The front workpiece W1 is switchably held and discharged by the first holding cancellation valve 24a and the second holding cancellation valve 24b. The rear workpiece W2 is switchably held and discharged by the third holding cancellation valve 24c and the fourth holding cancellation valve 24d.

Each holding cancellation valve <NUM> includes a third magnet <NUM> on the surface facing outward in the perpendicular direction D2. The third magnet <NUM> is, for example, a permanent magnet. In this embodiment, the third magnet <NUM> is provided on either end of the plate spring constituting the first holding cancellation valve 24a and the third holding cancellation valve 24c. Similarly, the third magnet <NUM> is provided on either end of the plate spring constituting the second holding cancellation valve 24b and the fourth holding cancellation valve 24d.

As shown in <FIG>, the conveyance track <NUM> includes a fourth magnet <NUM> at a position where the holding head <NUM> discharges the workpiece W, i.e., in the delivery part <NUM>. The fourth magnet <NUM> is, for example, an electromagnet. Energization and de-energization of the fourth magnet <NUM> is controlled by, for example, the control device <NUM>. The fourth magnet <NUM> is arranged to generate a magnetic force between the fourth magnet <NUM> and the third magnet <NUM> provided in the holding head <NUM> arriving at the delivery part <NUM>.

As shown in <FIG>, the holding cancellation valve <NUM> is switchably opened or closed by the magnetic force generated between the third magnet <NUM> and the fourth magnet <NUM>. In this embodiment, an attracting magnetic force is generated between the third magnet <NUM> and the fourth magnet <NUM>. When a magnetic force is generated between the magnets, the plate spring constituting the holding cancellation valve <NUM> is elastically deformed in a direction distanced from the base plate <NUM>. In other words, the holding cancellation valve <NUM> is put in an open state. This creates a gap G between the base plate <NUM> and the plate spring so that the open end of the branch pipe <NUM> communicates with the surrounding air. As a result, the atmospheric air is drawn into the vacuum pipe <NUM> via the branch pipe <NUM>, canceling the holding force (suction force) of the holding part <NUM>. When the magnetic force between the third magnet <NUM> and the fourth magnet <NUM> is lost, the plate spring returns to the original state and blocks the open end of the branch pipe <NUM>. In other words, the holding cancellation valve <NUM> is put into a closed state. As a result, the holding force of the holding part <NUM> is restored.

The fourth magnet <NUM> are arranged in each delivery part <NUM> one each on either side to sandwich the holding head <NUM> in the perpendicular direction D2. Further, the two fourth magnets <NUM> provided in each delivery part <NUM> are arranged with a displacement in the conveyance direction D1. More specifically, the fourth magnet <NUM> that faces the open ends of the first branch pipe 52a and the third branch pipe 52c is displaced rearward (upstream) in the conveyance direction D1 with respect to the fourth magnet <NUM> that faces the open ends of the second branch pipe 52b and the fourth branch pipe 52d. Therefore, the cancellation of the suction of the front workpiece W1 by the first suction hole group 30a occurs before the cancellation of the suction of the front workpiece W1 by the second suction hole group 30b. Further, the cancellation of the suction of the rear workpiece W2 by the third suction hole group 30c occurs before the cancellation of the suction of the rear workpiece W2 by the fourth suction hole group 30d.

By way of one example, the first holding cancellation valve 24a is opened first when the holding head <NUM> passes through the upstream delivery part <NUM> in the second track 4b or the third track 4c. This causes vacuum break in the front part of the front workpiece W1, causing the front part to be delivered to the laminating device <NUM>. When the holding head <NUM> advances further, the second holding cancellation valve 24b is opened. This causes vacuum break in the rear part of the front workpiece W1, causing the rear part to be delivered to the laminating device <NUM>. Further, when the front workpiece W1 is delivered to the laminating device <NUM>, the control device <NUM> cancels energization of the fourth magnet <NUM> until the holding head <NUM> passes through the upstream delivery part <NUM> completely.

This causes the holding head <NUM> to advance to the downstream delivery part <NUM>, maintaining adsorptive holding of the rear workpiece W2. The third holding cancellation valve 24c is opened to deliver the front part of the rear workpiece W2 to the laminating device <NUM> in the downstream delivery part <NUM>, and the fourth holding cancellation valve 24d is then opened to deliver the rear part of the rear workpiece W2 to the laminating device <NUM>. The rear workpiece W2 may be delivered to the laminating device <NUM> in the upstream delivery part <NUM>, and the front workpiece W1 may be delivered to the laminating device <NUM> in the downstream delivery part <NUM>.

As described above, the workpiece conveyance device <NUM> according to this embodiment includes the multiple holding heads <NUM> having the holding part <NUM> for holding the workpiece W and the vacuum pump <NUM> for generating a holding force in the holding part <NUM>, and the conveyance track <NUM> for conveying the multiple holding heads <NUM>. The vacuum pump <NUM> includes the pump unit <NUM> that communicates with the holding part <NUM> to suck the surrounding air via the holding part <NUM> and includes the shaft part <NUM> rotated to activate the pump unit <NUM>. The shaft part <NUM> includes the first magnet <NUM> magnetized to result in N poles and S poles alternating around the shaft. The conveyance track <NUM> includes the second magnet <NUM> extending in the conveyance direction D1 of the holding head <NUM>, the second magnet <NUM> being configured to alternately apply a magnetic force from the N pole and a magnetic force from the S pole in the conveyance direction D1 and being arranged to generate a magnetic force between the second magnet <NUM> and the first magnet <NUM> of the holding head <NUM> conveyed. By alternately switching the magnetic pole of the portion in the second magnet <NUM> applying a magnetic force to the first magnet <NUM>, the shaft part <NUM> is rotated, which causes the pump unit <NUM> to generate a holding force by sucking the surrounding air.

The workpiece conveyance device <NUM> of this embodiment is configured such that the vacuum pump <NUM> is mounted on the holding head <NUM>, and the action of the first magnet <NUM> and the second magnet <NUM> rotates the shaft part <NUM> to generate a holding force in the holding part <NUM>. It therefore makes it possible to omit installation of vacuum pipes and wirings that are necessary in the case the vacuum pump and the driving power supply are installed outside to move the holding head or in the case the driving power supply is installed outside to move the holding head carrying a vacuum pump. Accordingly, the design flexibility of the workpiece conveyance device <NUM> is increased.

Further, the second magnet <NUM> of this embodiment is rotated around the rotation axis Ax extending in the conveyance direction D1, and N poles and S poles are spirally formed around the rotation axis Ax. The magnetic pole of the portion in the second magnet <NUM> applying a magnetic force to the first magnet <NUM> is alternately switched in accordance with the rotation of the second magnet <NUM>. This makes it possible to continue rotating the shaft part <NUM> and maintain a holding force of the holding part <NUM> even when the holding head <NUM> comes to a stop. In the case the surface of the workpiece W delivered and the holding part <NUM> are both planar, for example, it is desired to deliver and receive the workpiece W by bringing the holding head <NUM> to a stop in order to mitigate the load exerted on the workpiece W when it is delivered. According to the holding head <NUM> of this embodiment capable of receiving the workpiece W in a stopped state, on the other hand, it is possible to deliver and receive the workpiece W between planar surfaces while at the same time mitigating the load on the workpiece W. If delivery takes place between curved surfaces or between a curved surface and a planar surface, it is possible to deliver and receive the workpiece W without applying a heavy load on the workpiece W even if the holding head <NUM> is kept moving.

Further, the vacuum pump <NUM> of this embodiment includes multiple pump units <NUM>. This makes it possible to organize the holding part <NUM> into multiple regions and generate a holding force in each region independently. It is also possible to extend the area of the holding part <NUM> or increase the holding force. Further, each pump unit <NUM> is activated by the rotation of the common shaft part <NUM> to generate a suction force. This can prevent the structure of the holding head <NUM> from becoming complicated due to an increase in the number of pump units <NUM>. Only one pump unit <NUM> may be provided, or the number of pump units <NUM> may be other than four.

The holding head <NUM> of this embodiment holds one workpiece W by means of at least two pump units <NUM>. Further, the holding head <NUM> holds multiple workpieces W. More specifically, the first pump unit 34a and the second pump unit 34b hold the front workpiece W1. Further, the third pump unit 34c and the fourth pump unit 34d hold the rear workpiece W2. By using two or more pump units <NUM> to hold one workpiece W, it is possible to discharge the workpiece W in multiple stages. This makes it possible to deliver the workpiece W to the laminating device <NUM> more accurately than otherwise. By causing the holding head <NUM> to hold multiple workpieces W, the throughput of the workpiece conveyance device <NUM> is increased. One workpiece W may be held by means of a single pump unit <NUM> or three or more pump units <NUM>. Further, the holding head <NUM> may hold one workpiece W or three or more workpieces W.

The holding head <NUM> of this embodiment includes the holding cancellation valve <NUM> that cancels the holding force of the holding part <NUM>. The holding cancellation valve <NUM> includes the third magnet <NUM>. The conveyance track <NUM> includes the fourth magnet <NUM> arranged at a position where the holding head <NUM> discharges the workpiece W so as to generate a magnetic force between the fourth magnet <NUM> and the third magnet <NUM>. The holding cancellation valve <NUM> is switchably opened or closed by the magnetic force generated between the third magnet <NUM> and the fourth magnet <NUM>. This makes it possible to cancel the holding force of the holding part <NUM> with a simple mechanism. Accordingly, the size of the vacuum pump <NUM> and, ultimately, the holding head <NUM> is prevented from becoming too large.

Further, the conveyance track <NUM> of this embodiment branches into multiple tracks. This increases the flexibility of arrangement of the destination of conveyance of the workpiece W. By arranging a device with a short takt time at the root of the branch of the conveyance track <NUM> and arranging a device with a long takt time at each destination of the branch, the production speed of the device with a short takt time is prevented from being sacrificed.

The workpiece W of this embodiment is a laminated sheet <NUM> in which the electrode plate and the separator are laminated. The conveyance track <NUM> includes the reception part <NUM> where the holding head <NUM> receives the laminated sheet <NUM> from the laminated sheet manufacturing device <NUM> and includes the delivery part <NUM> where the holding head <NUM> discharges the laminated sheet <NUM> to the laminating device <NUM>. Multiple delivery parts <NUM> are provided for one reception part <NUM>.

The takt time of the laminated sheet manufacturing device <NUM> (the time required to manufacture the laminated sheet <NUM> and deliver it to the holding head <NUM>) tends to be shorter than the takt time of the laminating device <NUM> (the time required to manufacture the laminated electrode body <NUM> and retrieve it from the lamination stage 200b). By providing multiple delivery parts <NUM> for one reception part <NUM>, therefore, the production speed of the laminated electrode body <NUM> is increased. The delivery part <NUM> is provided in each destination of the branch of the conveyance track <NUM>. This can suppress the conveyance track <NUM> from becoming too long as compared with the case of arranging the multiple delivery parts <NUM> in series.

In further accordance with the workpiece conveyance device <NUM> of this embodiment, electric power can be generated by using the rotation of the shaft part <NUM>. The electric power obtained from this can be used, for example, as a drive source of sensors mounted on the holding head <NUM>.

Embodiment <NUM> has a configuration common to embodiment <NUM> except for the structure of the second magnet <NUM>. The following description of this embodiment highlights features different from those of embodiment <NUM>, and the description of the common features will be simplified or omitted.

<FIG> shows a mechanism for rotating the shaft part <NUM> in the workpiece conveyance device <NUM> according to embodiment <NUM>. As in embodiment <NUM>, the second magnet <NUM> of this embodiment alternately generates a magnetic force from the N pole and a magnetic force from the S pole in the conveyance direction D1 of the holding head <NUM>. By way of one example, the second magnet <NUM> is magnetized to result in N poles and S poles alternating in the conveyance direction D1 of the holding head <NUM>. Meanwhile, the second magnet <NUM> of this embodiment, unlike that of embodiment <NUM>, is not rotated around the rotation axis Ax. In this configuration, too, the magnetic pole of the portion in the second magnet <NUM> applying a magnetic force to the first magnet <NUM> is alternately switched in accordance with the conveyance (movement) of the holding head <NUM>. This rotates the shaft part <NUM> and activates the first pump unit 34a-the fourth pump unit 34d.

Thus, the workpiece conveyance device <NUM> of this embodiment also increases the design flexibility of the workpiece conveyance device <NUM>. In the workpiece conveyance device <NUM> of this embodiment, it is necessary to keep moving the holding head <NUM> to maintain the holding force of the holding part <NUM>, but the mechanism for rotating the second magnet <NUM> is omitted so that the structure of the workpiece conveyance device <NUM> is simplified.

Embodiments of the present disclosure have been described above in detail. The embodiments described above are merely specific examples of practicing the present disclosure. The details of the embodiments shall not be construed as limiting the technical scope of the present disclosure. A number of design modifications such as modification, addition, deletion, etc. of constituting elements may be made to the extent that they do not depart from the idea of the invention defined by the claims. New embodiments with design modifications will provide the combined advantages of the embodiment and the variation. Although the details subject to such design modification are emphasized in the embodiments by using phrases such as "of this embodiment" and "in this embodiment", details not referred to as such are also subject to design modification. Any combination of constituting elements included in the respective embodiments is also useful as an embodiment of the present disclosure. Hatching in the cross section in the drawings should not be construed as limiting the material of the hatched object.

In embodiments <NUM>, <NUM>, the suction force as the holding force is generated by using the pump unit <NUM> to suck the surrounding air via the holding part <NUM>. Alternatively, the holding force may be generated by using the pump unit <NUM> to discharge the surrounding air to the holding part <NUM>. For example, the holding part <NUM> is comprised of a driving mechanism such as a cylinder for driving a target in response to a pressure and a gripping claw, etc. driven by the driving mechanism to switchably grip and discharge the workpiece W. The air outlet <NUM> of the pump unit <NUM> and the holding part <NUM> communicate via the vacuum pipe <NUM>. When the pump unit <NUM> is driven, the surrounding air is discharged to the holding part <NUM> to give a pressure to the driving mechanism. This causes the gripping claw to grip the workpiece W. In other words, it is possible to generate a holding force in the holding part <NUM> by using the pump unit <NUM> to discharge the surrounding air to the holding part <NUM>.

The second magnet <NUM> of embodiments <NUM>, <NUM> is a permanent magnet magnetized to result in N poles and S poles alternating in the conveyance direction D1 of the holding head <NUM>. Alternatively, the second magnet <NUM> may be comprised of an electromagnet. <FIG> is a perspective view of a part of the second magnet <NUM> provided in the workpiece conveyance device <NUM> according to variation <NUM>.

The second magnet <NUM> of variation <NUM> has, by way of one example, a structure in which multiple substantially U-shaped magnetic members <NUM> in which a coil <NUM> is wound are arranged in series in the conveyance direction D1. By inducing a current in the coil <NUM> wound around the middle part of each magnetic member <NUM>, a magnetic force is generated at a first end 60a and a second end 60b. The first end 60a of each magnetic member <NUM> is contiguous in the conveyance direction D1 and is arranged to generate a magnetic force between the magnetic member <NUM> and the first magnet <NUM> of the holding head <NUM> conveyed. Each coil <NUM> is energized to generate magnetic forces from different poles in adjacent first ends 60a. In this manner, the second magnet <NUM> alternately generates a magnetic force from the N pole and a magnetic force from the S pole in the conveyance direction D1 of the holding head <NUM>. Energization of each coil <NUM> is controlled by, for example, the control device <NUM>.

Claim 1:
A workpiece conveyance device (<NUM>) comprising:
a plurality of holding heads (<NUM>) that include a holding part (<NUM>) that holds a workpiece (W) and a vacuum pump (<NUM>) that generates a holding force in the holding part (<NUM>); and
a conveyance track (<NUM>) that conveys the plurality of holding heads (<NUM>), wherein
the vacuum pump (<NUM>) includes a pump unit (<NUM>) that connects with the holding part (<NUM>) to suck a surrounding air from the holding part (<NUM>) or to discharge the surrounding air to the holding part (<NUM>), the vacuum pump (<NUM>) further including a shaft part (<NUM>) that is rotated to activate the pump unit (<NUM>), characterised in that
the shaft part (<NUM>) includes a first magnet (<NUM>) magnetized in an alternating N poles and S poles around a shaft,
the conveyance track (<NUM>) includes a second magnet (<NUM>) extending in a conveyance direction (D1) of the holding head (<NUM>), the second magnet (<NUM>) alternately generating a magnetic force from the N pole and a magnetic force from the S pole in the conveyance direction (D1) and being arranged to generate a magnetic force between the second magnet (<NUM>) and the first magnet (<NUM>) of the holding head (<NUM>) conveyed, and
by alternately switching a magnetic pole of a portion in the second magnet (<NUM>) applying a magnetic force to the first magnet (<NUM>), the shaft part (<NUM>) is rotated, which causes the pump unit (<NUM>) to generate a holding force by sucking or discharging the surrounding air.