JP2014101221A - Strip carrier device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a strip carrier device capable of preventing thickness from being changed due to action of a compressive force, while performing tension separation during conveyance.SOLUTION: In a carrier device 15 for conveying a strip 12, a tension separation roll 21 for separating tension of the strip 12 on front and rear sides in a conveyance direction is provided midway through a conveyance path. The tension separation roll 21 can rotate at a constant speed and suck in the strip 12 by negative pressure. Thus, the thickness of the strip 12 is prevented from being changed due to action of a compressive force, while tension separation for the strip 12 is performed during conveyance.

Description

  The present invention relates to a belt-like body conveying apparatus.

2. Description of the Related Art Conventionally, an apparatus for conveying a belt-like body such as a long sheet or film is known. For example, this transport device may be used as a transport device in the middle of unrolling a long roll-shaped belt having a length of several hundred meters and winding it into a roll again.
In the process of unwinding and winding the roll-shaped strip in this way, in order to reduce the man-hours such as the work of switching the roll-shaped strip, the roll-shaped strip is improved. The further lengthening of this is desired.
When the strip is elongated in this way, a so-called winding deviation may occur in the roll-shaped strip on the winding side. In order to prevent this winding deviation, generally, the tension applied to the band-like body is increased as the length of the band-like body is increased. However, when the tension for unwinding the belt-like body increases, wrinkles or the like may occur in the roll-like belt-like body on the unwinding side.
In other words, in order to efficiently prevent the occurrence of winding deviation on the winding side and the generation of wrinkles on the winding side, it is necessary to separate the tension between the winding side and the winding side. So, while transporting the strip, the tension on the winding side is increased by sandwiching and transporting the strip by a so-called nip roll that has two opposing rolls and is driven to rotate at a constant speed. A technique for performing tension separation for reducing the tension has been proposed (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 11-244062

  However, when the nip roll described above is used, the belt-like body 112 is sandwiched between the two rolls 121a and 121b and a compressive force is applied in the thickness direction as shown in FIG. As a result, the thickness dimension may decrease. Even if the reduction in the thickness of the belt-like body 112 due to the sandwiching of the nip rolls is very small, when it is desired to obtain the external dimension accuracy in the formed body formed by laminating the belt-like body 112, There is a problem that the outer dimensions may deviate from the design values by the number of formed bodies arranged, and as a result, the outer dimensions may deviate greatly from the desired outer dimensions. In FIG. 5, the direction of tension before and after the nip roll is indicated by white arrows.

  The present invention has been made in view of the above circumstances, and provides a belt-like body conveyance device capable of preventing a change in thickness due to a compression force acting while performing tension separation during conveyance. is there.

In order to solve the above problems, the following configuration is adopted.
The belt-shaped body transport device according to the present invention includes a tension separating roll that separates the tension of the belt-shaped body before and after the transport direction in the middle of the transport path in the transport device that transports the belt-shaped body, The belt-like body is capable of rotating at a constant speed and is capable of sucking the belt-like body by a negative pressure.
By configuring in this way, even if the belt-like body is not sandwiched like a nip roll and the tension separation is not performed, the belt-like body is adsorbed to the tension separation roll by a negative pressure suction force, for example, before the tension separation roll. The tension before and after the tension separation roll can be separated, for example, by lowering the tension of the belt-like body below the tension of the belt-like body after the tension separation roll. As a result, it is possible to prevent the thickness of the band from changing due to a compressive force acting on the band while performing tension separation during conveyance of the band.

Furthermore, the belt-shaped body conveyance device according to the present invention is a guide for setting the holding angle of the belt-shaped body with respect to the tension separation roll to a predetermined value or more before and after the tension separation roll in the conveyance direction of the belt-shaped body. A member may be provided.
By comprising in this way, a tension | tensile_strength separation roll can be provided with sufficient adsorption | suction force necessary for carrying out tension | tensile_strength separation.

  According to the belt-shaped body conveyance device according to the present invention, it is possible to prevent a change in the thickness of the belt-shaped body from occurring due to the compression force acting while performing tension separation of the belt-shaped body during transportation.

It is a perspective view which shows the roll-shaped positive electrode material in embodiment of this invention. It is sectional drawing of the positive electrode material which follows the AA line of the said FIG. It is a figure which shows schematic structure of the unwinding apparatus, winding apparatus, and conveying apparatus in embodiment of this invention. It is a figure which shows the holding angle of the vacuum suction roll in the said conveying apparatus. It is a figure which shows schematic structure of a conveying apparatus provided with a general nip roll.

Next, a belt-like body conveyance device according to an embodiment of the present invention will be described with reference to the drawings.
In this embodiment, a positive electrode material for forming a positive electrode plate such as a lithium secondary battery will be described as an example of a long strip.
A lithium secondary battery or the like has a laminate in which a positive electrode plate and a negative electrode plate are laminated via a separator. The positive electrode plate of such a lithium secondary battery is formed from a long sheet-like positive electrode material 12 as shown in FIGS. The positive electrode material 12 is obtained by applying a layer 11 of an electrode active material (hereinafter simply referred to as an electrode active material layer 11) to a predetermined thickness uniformly on the front and back surfaces of a current collector 10 made of a metal foil such as aluminum. The coating part 13 is formed. Moreover, the uncoated part 14 in which the front and back surfaces of the current collector 10 are exposed without being coated with the electrode active material is formed at both ends in the width direction of the positive electrode material 12. Such a positive electrode material is unwound and used as necessary by being wound into a long roll and set in an unwinding device. Generally, the unwound positive electrode material is transported by a dedicated transport device and used for the next step such as winding.

  Here, the battery capacity of the battery described above is determined mainly depending on the thickness of the electrode active material layer 11. The electrode active material layer 11 is subjected to strict thickness management, for example, about ± 3 microns, using a not-shown pressing device or the like. However, in the above battery, there is a case where the structure of one film in which a separator is wrapped between a positive electrode plate and a negative electrode plate is packed into a case in units of several hundred sets to form one battery. If the deviation is 3 microns, for example, 300 mm will cause a deviation of 1 mm. Due to this thickness deviation, the battery capacity varies.

  FIG. 3 shows the unwinding device 30, the winding device 32, and the conveying device 15 arranged between the unwinding device 30 and the winding device 32 according to this embodiment.

  The unwinding device 30 is a device that sequentially unwinds the roll-shaped positive electrode material 12, and the roll-shaped positive electrode material 12 can be set on the rotating shaft 31. The rotating shaft 31 of the unwinding device 30 can be rotated in a predetermined unwinding direction at a speed set in advance by a drive source (not shown) such as a motor. By the rotation of the rotation shaft 31, the roll-shaped positive electrode material 12 is sequentially unwound and sent to the transport device 15. The roll-shaped positive electrode material 12 is replaced at an appropriate timing such that the remaining amount falls below a predetermined amount.

  On the other hand, a winding device 32 is installed on the downstream side of the transport device 15. The sheet-like positive electrode material 12 conveyed by the conveying device 15 is again wound into a roll shape by the winding device 32. The winding device 32 has a rotating shaft 33 that is rotated in a predetermined winding direction, and the positive electrode material 12 that has been conveyed by the conveying device 15 when the rotating shaft 33 is rotationally driven. Is again rolled. Here, the rotation speed of the rotation shaft 33 of the winding device 32 can be set separately from the rotation speed of the rotation shaft 31 of the unwinding device 30 described above.

  The transport device 15 includes a plurality of, more specifically, three first idle rolls 20a to 20c constituting a transport path. These first idle roll 20a to third idle roll 20c have an axis that faces the same direction as the axis of the positive electrode material 12 on the unwinding side, and are rotatable about this axis. A vacuum suction roll 21 is disposed in the middle of the transport path between the second idle roll 20b and the third idle roll 20c.

  The vacuum suction roll 21 has a function of separating tension on the upstream (front) side and the downstream (rear) side in the transport direction. The vacuum suction roll 21 is connected to a suction device (not shown) such as a vacuum pump for making the inside thereof a negative pressure, and a plurality of through holes (not shown) for sucking air are formed on the outer peripheral surface thereof. ) Is formed. That is, the sheet-like positive electrode material 12 in contact with the vacuum suction roll 21 is attracted to the outer peripheral surface of the vacuum suction roll 21 with an adsorption force according to the negative pressure.

  Further, the vacuum suction roll 21 can be rotated in the transport direction at a predetermined constant speed by a drive source such as a motor. The tension applied to the positive electrode material 12 upstream of the vacuum suction roll 21 is determined by the rotational speed of the vacuum suction roll 21 and the rotational speed of the rotating shaft 31 of the unwinding device 30 described above. The tension applied to the positive electrode material 12 on the downstream side of the vacuum suction roll 21 is determined by the rotational speed of the roll 21 and the rotational speed of the rotary shaft 33 of the winding device 32 described above. Then, the positive electrode material 12 conveyed upstream from the vacuum suction roll 21 has a higher tension than the positive electrode material 12 conveyed downstream from the vacuum suction roll 21. The rotational speed of the moving shafts 31 and 33 is set. The tension acting on the positive electrode material 12 conveyed upstream of the vacuum suction roll 21 is set to a high tension that does not cause winding deviation in the winding device 32. On the other hand, the tension acting on the positive electrode material 12 conveyed downstream from the vacuum suction roll 21 is set to a low tension that does not cause wrinkles on the positive electrode material 12 of the unwinding device 30. In FIG. 3, the direction of tension between the upstream side and the downstream side of the vacuum suction roll 21 is indicated by white arrows.

  Here, FIG. 4 shows the holding angle θ at which the vacuum suction roll 21 and the sheet-like positive electrode material 12 are in contact with each other. When the negative pressure generated by a suction device such as a vacuum pump is constant, the suction force by which the vacuum suction roll 21 sucks the sheet-like positive electrode material 12 increases as the holding angle θ increases. The suction force by the vacuum suction roll 21 is set to a suction force that does not slide on the vacuum suction roll 21 even when the sheet-like positive electrode material 12 is pulled by the tension described above.

  The vacuum suction roll 21, the second idle roll 20b, and the third idle roll 20c are arranged so that the positions where the positive electrode material 12 contacts are opposite to each other with respect to the center of each axis. The holding angle θ of the vacuum suction roll 21 can be adjusted by displacing the arrangement of the second idle roll 20b and the third idle roll 20c with respect to the vacuum suction roll 21, for example, 30 ° or more. More specifically, the angle is preferably set to 30 ° to 180 ° from the viewpoint of adsorption power. In addition, the larger the diameter of the vacuum suction roll 21, the better the contact area with the sheet-like positive electrode material 12, but this is preferable. In addition, since the electrode active material layer 11 may be peeled off even when the outer diameter of the vacuum suction roll 21 is too small, the vacuum suction roll 21 is preferably φ50 to φ300 mm, more preferably φ100 to 200 mm.

  Therefore, according to the belt-like body conveyance device 15 of the above-described embodiment, the sheet-like positive electrode material 12 can be attracted by a negative pressure even if the sheet-like positive electrode material 12 is not sandwiched and the tension separation is not performed like a nip roll. Is adsorbed by the vacuum suction roll 21, and the tension of the sheet-like positive electrode material 12 upstream of the vacuum suction roll 21 is reduced below the tension of the sheet-like positive electrode material 12 downstream of the vacuum suction roll 21. The tension in the upstream and downstream of the vacuum suction roll 21 can be separated. As a result, a compressive force is applied to the positive electrode material 12 while performing tension separation during the conveyance of the positive electrode material 12, and the thickness of the positive electrode material 12, especially the thickness of the electrode active material layer 11, is sandwiched by the roll and changes to the decreasing side. Can be prevented.

  Furthermore, the holding angle of the sheet-like positive electrode material 12 is changed by displacing the relative arrangement of the second idle roll 20b on the upstream side and the downstream side of the vacuum suction roll 21 and the third idle roll 20c and the vacuum suction roll 21. Therefore, it is possible to give the tension separating roll a necessary and sufficient adsorption force for tension separation.

In addition, this invention is not restricted to the structure of embodiment mentioned above, A design change is possible in the range which does not deviate from the summary.
In the above embodiment, an example of providing three idle rolls from the first idle roll 20a to the third idle roll 20c has been described, but the number of idle rolls is not limited to three.

  Moreover, although the conveying apparatus 15 of embodiment mentioned above adjusted the holding angle of the sheet-like positive electrode material 12 with respect to the vacuum suction roll 21 with the 2nd idle roll 20b and the 3rd idle roll 20c, a sheet-like A guide member that can guide the positive electrode material 12 and adjust a holding angle is not limited to a rotatable member. Moreover, although the case where arrangement | positioning of the 2nd idle roll 20b and the 3rd idle roll 20c was changed was demonstrated, you may displace the vacuum suction roll 21. FIG.

  Furthermore, in the above-described embodiment, the positive electrode material 12 that forms a positive electrode plate such as a lithium secondary battery has been described as an example of the belt-like body. However, the embodiment is not limited to the positive electrode material 12, but a sheet shape, a film shape, or the like. Therefore, it can be applied as a transport device for transporting a long belt-like body that requires strict thickness management.

  Moreover, in embodiment mentioned above, although the case where the rotating shaft 31 was inserted and rotated in the center of the roll-shaped positive electrode material 12 in the unwinding apparatus 30 was demonstrated, roll-shaped positive electrode material can be rotated. If it is, it will not be restricted to what uses the rotating shaft 31, and similarly in the winding device 30, if the roll-shaped positive electrode material 12 can be wound up, it will not be restricted to what uses the rotating shaft 33. FIG.

  Furthermore, although the positive electrode material 12 described above has the electrode active material layer 11 formed on the front and back surfaces, the positive electrode material 12 may be provided on either the front or back surface.

12 Positive electrode material (band)
15 Transport device 21 Vacuum suction roll 21 (tension separation roll)
20b Second idle roll (guide member)
20c Third idle roll (guide member)

Claims (2)

In the transport device that transports the belt-like body, a tension separating roll that separates the tension of the belt-like body before and after the transport direction in the middle of the transport path,
The belt separating apparatus according to claim 1, wherein the tension separating roll is capable of rotating at a constant speed and capable of sucking the band by negative pressure.   2. The belt-shaped body conveyance device according to claim 1, further comprising a guide member that sets a holding angle of the belt-shaped body with respect to the tension separation roll to a predetermined value before and after the tension separation roll in the conveyance direction.

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