Patent Application
20110131799
The present invention relates to a method for manufacturing electrode sheets. The electrode sheets are suitable, for example, for a wound electrode body of a secondary battery (storage battery).
A method for manufacturing electrode sheets is disclosed, for example, in Patent document 1. As described in the patent application, a belt-shaped member in which an active material layer has been formed on a collector is cut, while being conveyed, in the conveying direction. A plurality of cutting blades are arranged in the traveling direction of the belt-shaped member, the central portion in the widthwise direction of the belt-shaped member is first cut and then battery electrodes positioned at both side portions of the belt-shaped member are finally cut. As a result, the appearance of burrs at the end surface of the electrode can be prevented.
Further, Patent document 2 discloses a technique for manufacturing electrode sheets in which an electrode material is coated in stripes on a belt-shaped collector perpendicularly to the lengthwise direction, so that uncoated sections remain in a predetermined gap between the stripes and the belt-shaped collector is slit in the widthwise direction.
Patent document 3 describes an invention relating to a mechanism that adjusts a tension of a pass line of a nickel-plated felt that arrives from a pressurizing device into a drying device via a coating device. More specifically, a configuration is disclosed in which a pre-tension imparting means and an after-tension imparting means that impart a constant tension are provided in a pass line before and after the coating device.
Further, Patent document 4 discloses an apparatus that corrects distortions in the thickness direction of an electrode sheet.
The inventors considered the possibility of obtaining a plurality of electrode sheets, as shown in
As mentioned hereinabove, the original sheet 1 is rolled with rollers and the density of the electrode material 11, 12, 13 is increased. The inventors have found out that wrinkles occur in the metal foil 10 in this process. In order to manufacture electrode sheets of good quality, it is desirable that the occurrence of such wrinkles be inhibited. The present invention has been created with the object of inhibiting the occurrence of such wrinkles.
The method for manufacturing electrode sheets in accordance with the present invention has a first cutting step and a pressing step. In the first cutting step, an original sheet including a belt-shaped metal foil and an electrode material coated thereon in a lengthwise direction and having coated portion coated with the electrode material in a lengthwise direction to form a plurality of coated portions spaced at a predetermined gap, is cut at a predetermined location between the coated portions coated with the electrode material, to form original sheet strips. In the pressing step, the original sheet strips having been cut in the first cutting step are pressed.
With such a manufacturing method the original sheet is cut at a location between the coated portions having been coated with the electrode material before the pressing step. In the pressing step, the original sheet strips having been cut in such a manner are pressed. Therefore, the original sheet strips do not interfere with each other in the pressing step and the occurrence of wrinkles in the metal foil can be inhibited.
In the pressing step, the original sheet strips having been cut in the first cutting step and arranged side by side in a widthwise direction may be pressed by sandwiching the original sheet strips between a pair of rolls. In this case, because the pressing can be conducted with a pair of rolls, the conveying path is not complex, the equipment cost can be reduced, and space can be saved. Further, settings of rolling the original sheet strips to obtain uniform electrode sheets can be easily made and therefore the operability is good.
Further, a gap adjusting step of widening the gap between the plurality of original sheet strips having been cut in the first cutting step and supplying the original sheet strips to the pressing step may be provided between the first cutting step and the pressing step. The gap adjusting step makes it possible to prevent the end portions of the original sheet strips having been cut in the first cutting step from rubbing against each other.
Further, the speed adjusting step of adjusting the speed of the plurality of original sheet strips obtained in the first cutting step may be provided between the first cutting step and the pressing step, so that the speed of the original sheet strips that are supplied to the pressing step may be adjusted by the speed adjusting step. With the speed adjusting step, the difference in tension acting on the original sheet strips can be eliminated and the original sheet strips can be smoothly conveyed to the pressing step.
A second cutting step of cutting the original sheet strips, having been cut in the first cutting step, in the coated portions having been coated with the electrode material may be provided after the pressing step. As a result, it is possible to obtain an electrode sheet in which the coated portion is located at one widthwise end, from each of the original sheet strips.
In this case, a distortion correcting step of correcting distortions of the original sheet strips having been cut in the first cutting step may be provided after the pressing step and before the second cutting step. In the distortion correcting step, the uncoated portions are elongated more than the coated portions of the original sheet strips.
In the pressing step, the metal foil is elongated in the coated portions having been coated with the electrode material, but the elongation of the metal foil in the uncoated portions is less than that in the coated portions. As a result, distortions can appear in the original sheet strips. However, the distortion correcting step can correct these distortions.
An electrode sheet manufacturing apparatus in accordance with the present invention includes a conveying mechanism, a first cutting device, and a rolling device. The conveying mechanism conveys an original sheet. The first cutting device cuts the original sheet conveyed by the conveying mechanism. The rolling device is arranged downstream of the first cutting device in a conveying path of the conveying mechanism and presses the original sheet strips having been cut by the first cutting device. The conveying mechanism can convey the original sheet comprising a belt-shaped metal foil and an electrode material coated thereon so as to form a plurality of coated portions coated with the electrode material in a lengthwise direction and spaced at a predetermined gap. The first cutting device has a slitter arranged so as to be capable of cutting the original sheet at a location between coated portions coated with the electrode material.
With such a manufacturing apparatus, the original sheet is cut at a location between the coated portions coated with the electrode material by the first cutting device before the original sheet is supplied to the rolling device. Because the rolling device presses the cut original sheet strips, the original sheet strips do not interfere with each other and the occurrence of wrinkles in the metal foil can be inhibited.
In this case, a position adjusting mechanism configured to adjust a widthwise position of the original sheet fed to the first cutting device may be provided upstream of the first cutting device in the conveying path.
Further, the rolling device may have a pair of rolls, and the rolling device may press the original sheet strips having been cut by the first cutting device by arranging the original sheet strips side by side so as to be spaced at a gap in an axial direction of the rolls and sandwiching the original sheet strips between the pair of rolls. In this case, because the pressing is conducted with a pair of rolls, the conveying path is not complex and the equipment cost can be reduced. Further, the space can be saved. In addition, settings of rolling the original sheet strips to obtain uniform electrode sheets can be easily made and therefore the operability is good.
A gap adjusting device configured to widen a gap of the plurality of original sheet strips having been cut by the first cutting device may be provided in the conveying path between the first cutting device and the rolling device. As a result, end portions of the original sheet strips having been cut by the first cutting device can be prevented from rubbing against each other.
Further, a speed adjusting mechanism configured to adjust the speed of each of the plurality of original sheet strips having been cut by the first cutting device may be provided between the first cutting device and the rolling device in the conveying path, so that the speed of the original sheet strips fed to the rolling device is adjusted by the speed adjusting device. With such a speed adjusting mechanism, the difference in tension acting upon the original sheet strips can be eliminated and the original sheet strips can be smoothly conveyed to the rolling device.
A second cutting device configured to cut the original sheet strips having been cut by the first cutting device in coated portions coated with the electrode material may be provided downstream of the rolling device in the conveying path. As a result, electrode sheets in which the coated portions are on one side in the widthwise direction can be obtained from the original sheet strips.
A distortion correcting device may be provided between the rolling device and the second cutting device in the conveying path. For example, the distortion correcting device has a correction roller onto which the original sheet strips are caught, and a section of the correction roller that supports uncoated portions of the original sheet strips is thicker than a section that supports coated portions of the original sheet strips. In this case, the section of the correction roller that supports the uncoated portions on both widthwise ends of the original sheet strips may be replaceable.
In the rolling device, the metal foil elongates in the coated portions coated with the electrode material, but in the uncoated portions, the elongation of the metal foil is less than that in the coated portions. As a result, distortions can occur in the original sheet strips. However, these distortions can be corrected by the distortion correcting device.
Further, a position adjusting mechanism configured to adjust a widthwise position of the original sheet strips supplied to the second cutting device may be provided in the conveying path upstream of the second cutting device.
The method for manufacturing electrode sheets and the electrode sheet manufacturing apparatus can be used as a method for manufacturing electrode sheets and an apparatus therefor in the manufacture of a battery having a wound electrode body obtained by laminating and winding electrode sheets and belt-shaped separators together.
The electrode sheet manufacturing method and manufacturing apparatus of an embodiment of the present invention will be described below with reference to the appended drawings.
As shown in
The conveying mechanism 102 conveys an original sheet 1 has a plurality of coated portions 11, 12, 13 coated with an electrode material on a metal foil 10 (collector). In the present embodiment, the conveying mechanism 102 pulls the original sheet 1 from a feed reel 121 and successively conveys the original sheet 1 to the first cutting device 104, the gap adjusting device 106, the speed adjusting mechanism 108, the rolling device 110, the distortion correcting device 112, and the second cutting device 114. The conveying mechanism 102 is provided with a plurality of guide rollers 128 for guiding the original sheet 1. The original sheet 1 is cut by the first cutting device 104 and then further divided (cut) into a plurality of electrode sheets 5a to 5f by the second cutting device 114. Each of the plurality of electrode sheets 5a to 5f is wound into rolls by respective winding devices 126, 127.
As shown in
As shown in
The first cutting device 104 cuts the original sheet 1 conveyed by the conveying mechanism 102 as shown in
<<Position Adjusting Mechanism 120a>>
The position adjusting mechanism 120a is installed in the conveying path upstream of the first cutting device 104. The position adjusting mechanism 120a may use, for example, an EPC device (edge position control device) or a CPC device (center position control device) in which a detection device for detecting the position of the original sheet 1 is combined with a correction mechanism for correcting the position of the original sheet 1. As shown in
Both the EPC device and the CPC device can be used as a mechanism for adjusting the position of the original sheet 1. In particular, the EPC device may be used when the edge position is wished to be controlled, and the CPC device may be used when the center position is wished to be controlled. In the present embodiment, the EPC device is used as the position adjusting mechanism 120a for controlling the position of the original sheet 1 fed to the first cutting device 104.
The position adjusting mechanism 120a can adequately match the cutting lines z2, z4 of the original sheet 1 with the slitters 104a, 104b of the first cutting device 104.
The original sheet 1 having slits introduced into the cutting lines z2, z4 by the first cutting device 104 is fed to the gap adjusting device 106. As shown in
In the present embodiments, as shown in
The speed adjusting mechanism 108 adjusts a speed to feed the original sheet strips 1a, 1b, 1c cut by the first cutting device 104 to the rolling device 110.
In the present embodiment, where the gap of each of the original sheet strips 1a, 1b, 1c is adjusted by the gap adjusting device 106, a difference occurs each of the path lengths of the original sheet strips 1a, 1b, 1c. Further, in some cases, as the original sheet strips 1a, 1b, 1c do not have a uniform thickness in each of the coating portions 11, 12, 13, a difference occurs in rolling ratio (amount of the rolling) between the original sheet strips 1a, 1b, 1c in the rolling device 110. As shown in
In the present embodiment, the speed adjusting mechanism 108 is disposed upstream of the rolling device 110. The speed adjusting mechanism 108 selects the central original sheet strip 1b as a reference from among the original sheet strips 1a, 1b, 1c having been cut by the first cutting device 104, as shown in
In the present embodiment, the speed of the other original sheet strips 1a, 1c is adjusted by the speed adjusting mechanism 108 with reference to the central original sheet strip 1b. As a result, the difference in tension between the original sheet strips 1a, 1b, 1c fed to the rolling device 110 can be eliminated and therefore the original sheet strips 1a, 1b, 1c can be smoothly conveyed to the rolling device 110.
In the present embodiment, the speed adjusting mechanism 108 adjusts the speed of the other original sheet strips 1a, 1c with reference to the central original sheet strip 1b, but any of the original sheet strips 1a, 1b, 1c may be taken as the reference original sheet strip. The reference original sheet strip may be adequately selected with consideration for mechanical configuration.
The rolling device 110 will be described below.
As shown in
In the pressing step, the density of the electrode material can be increased by rolling the original sheet strips 1a, 1b, 1c and the performance of the battery per unit capacity can be increased. Further, by pressing with the rolling device 110, the original sheet strips 1a, 1b, 1c can be rolled and electrode sheets of adequate thickness can be obtained. As will be described below, the electrode sheets constituting a secondary battery are wound upon laminating with a separator interposed therebetween. In this case, where the electrode sheets have an adequate thickness, the spread in thickness of the wound bodies can be inhibited and displacement during winding can be also prevented.
In the present embodiment, as shown in
Therefore, when the original sheet strips are caused to pass through the rolling device 110, as shown in
The distortion correcting device 112 corrects the distortion of the original sheet strips 1a, 1b, 1c having been cut by the first cutting device 104. As shown in
As shown in
Where each of the original sheet strips 1a, 1b, 1c is caught on the correction rollers 112a, the uncoated portions (16, 18), (18, 19), (19, 17) at both widthwise ends are extended greater than the coated portions 11, 12, 13 in the intermediate sections. In particular, the sections 112a1, 112a2 that support the uncoated portions (16, 18), (18, 19), (19, 17) are enlarged in a taper-like fashion from the inside to the outside. As a result, the uncoated portions (16, 18), (18, 19), (19, 17) are uniformly extended in the lengthwise direction when passing through the correction roller 112a.
The amount of occurring distortion differs depending on such factors as the material and thickness of the metal foil and the coated amount of the electrode material. Therefore, the degree of tapering of the sections 112a1, 112a2 that support the uncoated portions 16, 18 ((18, 19), (19, 17)) may be adjusted by changing such factors as the material of the metal foil and amount of distortion.
In the present embodiment, as shown in
In the present embodiment, the configuration enables the replacement of the sections 112a1, 112a2 that support the uncoated portions 16, 18 ((18, 19), (19, 17)), as shown in
With the above-described distortion correcting device 112, as shown in
The original sheet strips 1a, 1b, 1c in which the distortions have been corrected by the distortion correcting device 112 are fed as shown in
The second cutting device 114 cuts the original sheet strips 1a, 1b, 1c at the coated portions 11, 12, 13 after pressing with the rolling device 110 as shown in
Thus, in the present embodiment, as shown in
In the present embodiment, the second cutting device 114 is provided with three slitters 114a, 114b, 114c correspondingly to the cutting lines z1, z3, z5. The positions of the three slitters 114a, 114b, 114c in the widthwise direction are fixed with respect to the conveying direction of the original sheet strips 1a, 1b, 1c. Therefore, the original sheet strips 1a, 1b, 1c have to be conveyed so that the centers of the coated portions 11, 12, 13 of the original sheet strips 1a, 1b, 1c in the widthwise direction match the slitters 114a, 114b, 114c. For this purpose, the position adjusting mechanism 120b is installed upstream of the second cutting device 114.
Further, in the present embodiment, a CPC device (center position control device) is used as the position adjusting mechanism 120b. In the position adjusting mechanism 120b, as shown in
Thus, the cutting lines z1, z3, z5 of the original sheet strips 1a, 1b, 1c can be adequately matched with the slitters 114a, 114b, 114c.
The slitters 114a, 114b, 114c that can adequately cut the metal foil 10 coated with the electrode material may be used in the second cutting device 114. For example, the slitters may be selected from the well-known slitters (cutters) that can perform the required function. Further, in the electrode sheets, the material and thickness of the metal foil and also the coated electrode material and the thickness thereof differ depending on the battery type and also on whether the electrode is a positive electrode or a negative electrode. Therefore, the slitters 114a, 114b, 114c may be advantageously used such that make it possible to change the cutting conditions adequately correspondingly to the original sheet strips 1a, 1b, 1c.
The plurality (six in the present embodiment) of the electrode sheets 5a to 5f can be obtained by dividing (cutting) the original sheet strips 1a, 1b, 1c with the second cutting device 114.
Further, in the present embodiment, as shown in
Further, in the present embodiment, the conveying path of the electrode sheet 5d and the conveying path of the original sheet 1 before it is cut by the first cutting device 104 are set along the same straight line z3 (in the present embodiment, z3 is a central line in the widthwise direction of the original sheet 1 before it is cut by the first cutting device 104). As a result, a tension acts adequately between the original sheet 1 before it is cut by the first cutting device 104 and the electrode sheets 5a to 5f that were divided (cut) by the second cutting device 114, and the original sheet 1 before the cutting can be adequately conveyed.
Thus, the electrode sheets 5a to 5f having been divided (cut) are wound up by winding devices 126, 127 as shown in
With the electrode sheet manufacturing apparatus 100, as shown in
Thus, as shown in
By contrast, in the present embodiment, the original sheet strips 1a, 1b, 1c that are pressed by the rolling device 110 are independent from each other. As a result, the effect produced by the rolling of the coated portions 11, 12, 13 remains in the original sheet strips 1a, 1b, 1c. Therefore, the distortions occurring in the original sheet strips 1a, 1b, 1c can be prevented from affecting each other and the occurrence of wrinkles can be inhibited.
Because the first cutting device 104 cuts only the uncoated portions 18, 19, the cutting conditions can be easily set. Thus, in the original sheet 1, as shown in
In the present embodiment, in the conveying mechanism the position adjusting mechanism 120a that adjusts the widthwise position of the original sheet 1 supplied to the first cutting device 104 is installed upstream of the first cutting device 104. Therefore, the positions of the cutting lines z2, z4 having been set for the uncoated portions 18, 19 of the original sheet 1 can be adequately matched with the first cutting device 104. As a result, the original sheet 1 can be accurately cut by the cutting lines z2, z4.
In the present embodiment, as shown in
Further, in the present embodiment, the speed adjusting mechanism 108 is provided in the conveying path between the first cutting device 104 and the rolling device 110. The speed conveying mechanism 108 adjusts the speed with which the original sheet strips 1a, 1b, 1c obtained by cutting by the first cutting device 104 are fed to the rolling device 110. Therefore, the tension of the original sheet strips 1a, 1b, 1c fed to the rolling device 110 can be adjusted and the original sheet strips 1a, 1b, 1c can be smoothly fed to the rolling device 110.
Further, in the present embodiment, as shown in
In this case, only the cutting lines z2, z4 having been set on the uncoated portions 18, 19 are cut by the first cutting device 104, and then the cutting lines z1, z3, z5 having been set on the coated portions 11, 12, 13 are cut by the second cutting device 114. Therefore, the cutting conditions of the second cutting device 114 can be easily set.
In the present embodiment, as shown in
Thus, as shown in
In the present embodiment, as shown in
Thus, in the present embodiment, the first cutting device 104 is provided, as shown in
Further, with the present embodiment, in the second cutting step, the plurality of original sheet strips 1a, 1b, 1c having been cut in the first cutting step arranged side by side to each other are cut. With such a configuration, it is not necessary to provide individual cutting devices for cutting the original sheet strips 1a, 1b, 1c and a configuration with a single cutting device can be used. The cutting conditions can be easily matched for the original sheet strips 1a, 1b, 1c. In this case, the conveying mechanism of the original sheet strips 1a, 1b, 1c is not made more complex, the equipment cost can be reduced, and the space can be saved.
The method for manufacturing electrode sheets of one embodiment of the present invention and the apparatus therefor are explained above, but the present invention is not limited to this embodiment.
For example, in the example shown above, the original sheet 1 has three coated portions coated with the electrode material, but the original sheet 1 can have more than three coated portions coated with the electrode material. Further, the dimensions in the drawings are appropriately simplified for the convenience of drafting and explanation. Therefore, the configuration of the apparatus 100 for manufacturing electrode sheets is not limited to that shown in the figure.
Further, the conveying mechanism may have general utility such that enables the use of the conveying mechanism even when the original sheet 1 is changed. Further, the positions of slitters in the first cutting device and second cutting device can be changed correspondingly to the cutting lines having been set on the coated portions and uncoated portions of the original sheet 1. The rolling device is preferably constituted by a pair of rollers, and the shape of rollers may be variously changed correspondingly to the original sheet 1. The present invention can be also variously changed irrespectively of the matters mentioned herein.
The electrode sheets obtained constitute, for example, a wound electrode body of various secondary batteries. For example, a lithium-ion secondary battery and a nickel-hydride secondary battery are examples of secondary batteries having a wound electrode body. An example of a lithium-ion secondary battery will be explained below.
A lithium-ion secondary battery is constituted, for example, as shown in
In the present embodiment, the wound electrode body 310 is provided, as shown in
In the present embodiment, the positive electrode sheet 311 is manufactured by coating an electrode material 311d including a positive electrode active material on both sides of a collector sheet 311c (corresponds to the metal foil 10) composed of an aluminum foil. Examples of the positive electrode active material contained in the electrode material 311d include lithium manganese oxide (LiMn2O4), lithium cobalt oxide (LiCoO2), and lithium nickel oxide (LiNiO2).
In the present embodiment, the negative electrode sheet 313 is manufactured by coating an electrode material 313d including a negative electrode active material on both sides of a collector sheet 313c (corresponds to the metal foil 10) composed of a copper foil. Examples of the negative electrode active material contained in the electrode material 313d include carbon-containing materials such as graphite and amorphous carbon and lithium-containing transition metal oxides or transition metal nitrides.
The separators 312, 314 are films that can transmit ionic substances. In the present embodiment, microporous polypropylene membranes are used.
In the present embodiment, the electrode materials 311d, 313d are coated on one side in the widthwise direction of the collector sheets 311c, 313c and not coated on the edge portion on the opposite side in the widthwise direction of the collector sheets 311c, 313c. In the positive and negative electrode sheets 311 and 313, the zones in which the collector sheets 311c, 313c are coated the electrode material 311d, 313d are called coated portions 311a, 313a, and zones in which the collector sheets 311c, 313c are coated the electrode material 311d, 313d are called uncoated portions 311b, 313b
In such a lithium-ion secondary battery, lithium ions pass through the belt-shaped separators 312, 314 between the coated portion 311a of the positive electrode sheet 311 and the coated portion 313a of the negative electrode sheet 313 during charging and discharging. In this case, it is preferred that the coated portion 311a of the positive electrode sheet 311 does not protrude beyond the coated portion 313a of the negative electrode sheet 313 in order to prevent the lithium ions from precipitating. By using a configuration in which the coated portion 311a of the positive electrode sheet 311 does not protrude beyond the coated portion 313a of the negative electrode sheet 313, it is possible to prevent the lithium ions from precipitating during charging and discharging.
In the present embodiment, as shown in
However, errors can occur in the manufacturing process or a widthwise displacement can occur when the positive electrode sheet 311, negative electrode sheet 313, and separators 312, 314 are laminated. Therefore, a difference (b−a) between the width (b) of the coated portion 313a of the negative electrode sheet 313 and the width (a) of the coated portion 311a of the positive electrode sheet 311 and a difference ((c1, c2)−b) between the widths (c1), (c2) of the first separator 312 and second separator 314 and the width (b) of the coated portion 313a of the negative electrode sheet 313 is set to predetermined distances to allow for such errors and displacement.
With the apparatus 100 for manufacturing electrode sheets according to the present invention, as shown in
As shown in
A plurality of such lithium-ion secondary batteries is assembled to configure a battery assembly 1000 which is installed, for example as shown in
Thus, the present invention is also useful as a method for manufacturing a secondary battery (storage battery) having a wound electrode body and a manufacturing apparatus therefor.
Another embodiment of the method for manufacturing electrode sheets and a manufacturing apparatus therefor will be described below.
In the above-described method for manufacturing electrode sheets, for example as shown in
The apparatus 400A shown in
The plurality of cut sheet strips 505a to 505f can be conveyed for example to a cleaner or an inspection device. In this case, for example as in the case of the apparatus 400A shown in
However, in this case, as shown in
By contrast in the configuration of the apparatus 400B shown in
In the mechanism A (step A), an original sheet 500 is cut into a plurality of sheet strips 505a to 505f, the adjacent sheet strips are guided separately to an upper conveying path and a lower conveying path, and the respective positions of the sheet strips 505a to 505f are adjusted in the upper and lower conveying paths. Thus, in the mechanism A, the apparatus 400 first cuts the original sheet 500 into a plurality of sheet strips 505a to 505f along the cutting lines z1 to z5 (see
In the mechanism B (step B), the apparatus 400B arranges the sheet strips 505a to 505f, for which the positions (gaps) have been adjusted in the upper and lower conveying paths, side by side so as to be spaced from each other widthwise, and guides the sheet strips to a single conveying path to convey the sheet strips.
In such an apparatus 400B, the original sheet 500 is cut into a plurality of sheet strips 505a to 505f by a cutting device 401. Then, the adjacent sheet strips from among the cut sheet strips 505a to 505f are separated in the vertical direction and conveyed. In the present embodiment, the sheet strips 505a, 505c, 505e with odd numbers from the right end in the conveying direction, from among the cut sheet strips 505a to 505f, are conveyed upward and the sheet strips 505b, 505d, 505f with even numbers are conveyed downward. As a result, in the sheet strips 505a to 505f having been cut by the cutting device 401, the edges of the adjacent sheet strips 505a to 505f are prevented from rubbing against each other.
Further, in the present embodiment, as shown in
<<Guide Roll Mechanism 403a, 403b>>
The apparatus 400B shown in
The guide roll mechanism 403a, 403b may use for example guide roll mechanisms that are used in CPC or EPC. Thus, guide roll mechanisms for EPC that are manufactured by Nireco Corporation (Japan) can be used as the guide roll mechanisms 403a, 403b. As the representative guide roll mechanisms for EPC, there are a guide roll mechanism of a center pivot system and a guide roll mechanism of an end pivot system. Appropriate guide roll mechanisms can be appropriately selected and used as the guide roll mechanisms 403a, 403b. By providing the guide roll mechanisms 403a, 403b in the upper and lower conveying paths, it is possible to control the positions (gaps) of the cut electrode sheets 505a to 505f in the upper and lower conveying paths with good accuracy.
In the apparatus 400B, each of the positions (gaps) of the upper sheet strips 505a, 505c, 505e and lower sheet strips 505b, 505d, 505f are adjusted by the above-described guide roll mechanisms 403a, 403b. Then, the sheet strips 505a to 505f are provided with a predetermined gap and conveyed side by side in the widthwise direction in a single conveying path. Thus, as shown in
The sheet strips 505a to 505f are conveyed side by side in the widthwise direction in a single conveying path so as to prevent the edges of the sheet strips 505a to 505f from rubbing against each other. For this purpose, the guide roll mechanisms 403a, 403b are provided in the upper and lower conveying paths respectively for the conveying paths of the sheet strips 505a to 505f. As a result, when the sheet strips 505a to 505f are conveyed in the single conveying path, the required gap can be generated between the sheet strips 505a to 505f so that the edges of the sheet strips 505a to 505f are prevented from rubbing against each other.
Further, in the present embodiment, the sheet strips 505a, 505c, 505e with odd numbers from the right end in the conveying direction, from among the cut sheet strips 505a to 505f, are conveyed upward, and the sheet strips 505b, 505d, 505f with even numbers are conveyed downward. Each of the positions (gaps) of the sheet strips 505a, 505c, 505e with odd numbers is adequately adjusted by the upper guide roller mechanism 403a. Each of the positions (gaps) of the sheet strips 505b, 505d, 505f with even numbers is adequately adjusted by the lower guide roll mechanism 403b. After the required gap has been generated between each of the sheet strips 505a to 505f, each of the sheet strips 505a to 505f is arranged in the order of 505a to 505f in the widthwise direction and guided toward the single conveying path.
With the apparatus 400B, as shown in
In this case, the cleaner 410 may be for example a device that can remove foreign matter that has adhered to the sheet strips 505a to 505f, while the plurality of sheet strips 505a to 505f having been arranged side by side so as to be spaced from each other widthwise are conveyed. Further, the inspection device 420 may be a device that conducts inspection, while the plurality of sheet strips 505a to 505f having been arranged side by side so as to be spaced from each other widthwise are conveyed. For example, a device that inspects a width or thickness of the electrode material coated on the sheet strips 505a to 505f and the coating positions on the sheet strips 505a to 505f can be used as the inspection device 420.
In the winding device 430, as shown in
The friction shaft 434 of the present embodiment is provided with a shaft portion 434a, torque-imparting rings 434b, and gap-maintaining rings 434c. The shaft portion 434a is a hollow rod-like member. The torque-imparting rings 434b and gap-maintaining rings 434c are alternately mounted on the outer circumferential surface of the shaft portion. A plurality of the winding reels 432 are mounted on the outer circumference of the friction shaft 434. Spacers 436 are inserted between the winding reels 432. The positions of the winding reels 432 are set with respect to the outer circumference of the friction shaft 434.
The winding reels 432 are disposed with a gap in the lengthwise direction correspondingly to the positions of the sheet strips 505a to 505f conveyed toward the winding device 430. Torque-imparting rings 434b are disposed on the inner circumferential side of the winding reels 432. In the shaft portion 434a of the friction shaft 434, the compressed air is supplied from the compressor C into the hollow portion.
The torque-imparting rings 434b generate a friction force with the winding reels 432 correspondingly to the air pressure in the hollow section of the shaft portion 434a. A required torque is caused to act upon the winding reels 432. In this case, where the air pressure increases in the hollow section of the shaft portion 434a, the friction force between the torque-imparting rings 434b and winding reels 432 increases. Further, where the air pressure decreases in the hollow section of the shaft portion 434a, the friction force between the torque-imparting rings 434b and winding reels 432 also decreases. The gap-maintaining rings 434c are ring members for maintaining the gap of the torque-imparting rings 434b. Further, the shaft portion 434a of the friction shaft 434 is connected to a motor M for rotating the friction shaft 434. The drive power of the motor M and the air pressure of the compressed air supplied from a compressor C are controlled by a control device S.
As described above, the friction shaft 434 is controlled by the air pressure of the compressor C and so adjusted as to generate a required torque that is necessary for the winding reels 432 to wind up the sheet strips 505a to 505f. Thus, in a case where the tension acting upon the sheet strips 505a to 505f is low, the sheet strips 505a to 505f are wound up by the winding reels 432 following the rotation of the friction shaft 434. Where the tension acting upon the sheet strips 505a to 505f rises to a predetermined value or above it, a slip occurs between the torque-imparting rings 434b of the friction shaft 434 and the winding reels 432. As a result, the tension acting upon the sheet strips 505a to 505f can be prevented from increasing abruptly.
Thus, in the winding device 430, a plurality of winding reels 432 are disposed with a gap correspondingly to the plurality of sheet strips 505a to 505f on the friction shaft 434. In the friction shaft 434, the torque acting upon the winding reels 432 can be adjusted. Therefore, by the winding device 430 the sheet strips 505a to 505f can be wound up so that the tension acting upon the sheet strips 505a to 505f is prevented from increasing excessively.
Thus, in the apparatus 400B shown in
When the plurality of sheet strips 505a to 505f are conveyed in a single conveying path, as described hereinabove, the tension acting upon the sheet strips 505a to 505f sometimes differ therebetween. When the tension acting upon the sheet strips 505a to 505f differs therebetween, a difference in tightening or loosening degree occurs between the sheet strips 505a to 505f in the conveying path. Where a difference in tightening or loosening degree between the sheet strips 505a to 505f increases, it can cause wrinkles or a large difference in hardness and length between the sheet strips 505a to 505f wound up by the winding reels 432.
Accordingly, it may be used as the guide rollers 402 in the case of conveying the plurality of sheet strips 505a to 505f that guide rollers can convey the plurality of sheet strips 505a to 505f correspondingly to the difference in tension acting upon the sheet strips 505a- to 505f.
For example, as shown in
The rotary shaft 441 is rotatably supported by bearings. In the present embodiment, the rotary shaft is rotatably mounted by using bearings 447 on a frame 446 that supports the guide roller 402. A plurality of tendency drive roller bearings 442 are mounted with a predetermined gap on the other circumferential surface of the rotary shaft 441. The tendency drive roller bearings 442 have a slip resistance higher than that of the bearings 447 supporting the rotary shaft 441. The shells 443 are members that guide the sheet strips 505a to 505f. The shells 443 are mounted on the outer rings of the tendency drive roller bearings 442.
Each shell 443 of the guider roller 402 is mounted on the rotary shaft 441 by the tendency drive roller bearing 442. In this case, the tendency drive roller bearing 442 absorbs by relative rotation of the rotary shaft 441 and shell 443 the tension acting upon the conveyed sheet strip 505a. Thus, each shell 443 is constituted by the so-called tendency drive roller.
Thus, the guide roller 402 conveys the sheet strips 505a to 505f having been arranged side by side so as to be spaced from each other widthwise by the plurality of shells 443 constituting the respective tendency drive rollers. In other words, in the guider roller 402, the shells 443 are rotated by the rotation of the rotary shaft 441 supported by the bearings 447. Further, the shells 443 are rotated appropriately relative to the rotary shaft 441 by the tendency drive roller bearings 442 correspondingly to the difference in tension acting upon the sheet strips 505a to 505f. As a result, a required difference is generated in the rotation speed of the shells 443 conveying the sheet strips 505a to 505f. Thus, the sheet strips 505a to 505f can be conveyed by the plurality of shells 443 mounted on a single rotary shaft 441, while allowing for a difference in tension acting upon the sheet strips 505a to 505f. Thus, the guide roller 402 can guide the sheet strips 505a to 505f having been arranged side by side so as to be spaced from each other widthwise, while allowing for a difference in tension.
As described hereinabove, the apparatus 400B, as shown in
For example, as shown in
The above-described apparatus 400B (see
| Number | Date | Country | Kind |
|---|---|---|---|
| 2008224456 | Sep 2008 | JP | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/JP2009/052719 | 2/17/2009 | WO | 00 | 9/15/2010 |
