Mixture sheet conveying device

Abstract

A conveyance device (1) is provided with a first roller (2) and a second roller (4), and the first roller (2) and the second roller (4) convey a mixture sheet (6) of a dry electrode mixture (8) by rotating the mixture sheet (6) therebetween. The first peripheral surface (2a) of the first roller (2) has a first surface roughness. A second peripheral surface (4a) of the second roller (4) has a second surface roughness greater than the first surface roughness. The second roller (4) is located downstream of the first roller (2) in the conveying direction of the mixture sheet (6), and supports and conveys the mixture sheet (6) passing through the gap (G) between the first roller (2) and the second roller (4) on a second circumferential surface (4a).

Description

Technical Field

[0001] The present disclosure relates to a delivery device for composite tablets. Background Art

[0002] Patent Document 1 describes an apparatus for conveying a mixture sheet obtained by molding a wet electrode mixture using a plurality of rollers.

[0003] [Prior Art Literature]

[0004] [Patent Document]

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2015-164717 Summary of the Invention

[0006] [Problems to be Solved by the Invention]

[0007] The present inventors studied the application of this conveying process to dry electrode mixture sheets containing less solvent than wet electrode mixture sheets and found that conveying dry electrode mixture sheets may result in lower conveying stability than conveying wet electrode mixture sheets.

[0008] The present disclosure has been made in view of such circumstances, and an object of the present disclosure is to provide a technology for improving the transport stability of a combined medication tablet.

[0009] [Technical solutions for solving technical problems]

[0010] One embodiment of the present disclosure is a device for conveying a composite sheet. The device includes a first roller and a second roller, which convey the composite sheet by sandwiching a composite sheet formed into a sheet of a dry electrode composite between the first and second rollers and rotating the rollers. The first circumferential surface of the first roller has a first surface roughness. The second circumferential surface of the second roller has a second surface roughness greater than the first surface roughness. The second roller is located downstream of the first roller in the conveying direction of the composite sheet, and supports and conveys the composite sheet passing through the gap between the first and second rollers using its second circumferential surface.

[0011] Optional combinations of the above-described constituent elements and modes of converting the expressions of the present disclosure into methods, apparatuses, systems, and the like are also applicable as additional modes of the present disclosure.

[0012] [Effects of the Invention]

[0013] According to the present disclosure, it is possible to improve the transport stability of the combined tablet. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the conveying device of the composite tablet according to the embodiment.

[0015] Figure 2 It is a schematic diagram of a conveying device according to a modified example.

[0016] Figure 3 It is a figure which shows the conditions and evaluation results of the conveying apparatus of each Example and each comparative example. DETAILED DESCRIPTION

[0017] Hereinafter, the present disclosure will be described based on preferred embodiments and with reference to the accompanying drawings. The embodiments do not limit the present disclosure but are illustrative, and not all features and combinations thereof described in the embodiments are essential contents of the present disclosure. The same or equivalent components, members, and processes shown in the drawings are marked with the same figure numerals, and repeated descriptions are appropriately omitted. In addition, the scales and shapes of the various parts shown in the figures are conveniently set for ease of description, and are not to be interpreted as limiting unless otherwise specified. In addition, when terms such as "first" and "second" are used in this specification or claims, unless otherwise specified, the terms do not indicate any order or importance, but are used to distinguish a certain configuration from other configurations. In addition, in the drawings, part of the unimportant components is omitted for the purpose of explaining the embodiments.

[0018] Figure 1 This is a schematic diagram of a conveying device 1 for a composite sheet 6 according to an embodiment. The conveying device 1 for a composite sheet 6 (hereinafter referred to as "conveyor device 1") includes a first roller 2 and a second roller 4. The first roller 2 and the second roller 4 are positioned so that their respective rotation axes are parallel to each other and are adjacent to each other at a predetermined distance. Furthermore, the second roller 4 is positioned downstream of the first roller 2 in the conveying direction of the composite sheet 6.

[0019] The composite sheet 6 passes through the gap between the first roller 2 and the second roller 4. The composite sheet 6 is a sheet material formed by compressing the powdered or granular dry electrode composite 8 as a raw material. As an example, the composite sheet 6 is supplied from a forming device 10 to the gap between the first roller 2 and the second roller 4. The forming device 10 includes a storage unit 12 and a pair of forming rollers 14. The storage unit 12 is, for example, a well-known hopper and stores the dry electrode composite 8.

[0020] A pair of forming rollers 14 is arranged at the powder outlet of the storage section 12. The pair of forming rollers 14 are positioned so that their respective rotation axes are parallel to each other, and are adjacent to each other at a predetermined interval. The pair of forming rollers 14 places the dry electrode mixture 8 in the storage section 12 on each peripheral surface and supplies it to the gap between the two forming rollers. Therefore, the pair of forming rollers 14 also functions as feed rollers. The pair of forming rollers 14 rotate in opposite directions to each other, compressing the dry electrode mixture 8 supplied to the gap into a sheet. Thus, the mixture sheet 6 is formed. The mixture sheet 6 is continuously fed out from the gap between the pair of forming rollers 14. Therefore, the mixture sheet 6 is in the form of a strip that is long in the conveying direction. In addition, the structure of the forming device 10 is not limited to the above structure.

[0021] The dry electrode mixture 8 contains an electrode active material and a binding material, i.e., a binder. Furthermore, it contains a conductive agent and a solvent as needed. The binding material and the solvent function as binding components that bind the electrode active materials together. In the case of a general lithium-ion secondary battery, the electrode active material is lithium cobalt oxide, lithium iron phosphate, etc. if it is the positive electrode, and graphite, etc. if it is the negative electrode. The conductive agent is graphite, carbon black, acetylene black, etc. The binding material is polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVdF), etc.

[0022] When the dry electrode mixture 8 is used for the negative electrode, examples of the solvent include water; alcohols such as ethanol; N-methylpyrrolidone (NMP); toluene; dimethyl carbonate (DMC); ethyl methyl carbonate (EMC); and the like. Furthermore, when the dry electrode mixture 8 is used for the positive electrode, examples of the solvent include amine solvents such as N,N-dimethylaminopropylamine and diethylenetriamine; ether solvents such as tetrahydrofuran; ketone solvents such as methyl ethyl ketone; ester solvents such as methyl acetate; and amide solvents such as dimethylacetamide and N-methyl-2-pyrrolidone.

[0023] In this embodiment, "dry" means that the solvent content is 5% by mass or less relative to the total mass of the dry electrode mixture 8. Alternatively, the solvent content may be 3% by mass or less, 0.1% by mass or less, or substantially 0% by mass relative to the total mass of the dry electrode mixture 8. Using a dry electrode mixture 8 can eliminate or simplify the drying oven for the mixture sheet 6.

[0024] The first roller 2 and the second roller 4 sandwich the composite sheet 6 and rotate in opposite directions to convey the composite sheet 6. After passing through the gap between the first roller 2 and the second roller 4, the composite sheet 6 is supported by the second peripheral surface 4a and conveyed.

[0025] The circumferential surface of the first roller 2 (hereinafter appropriately referred to as the first circumferential surface 2a) and the circumferential surface of the second roller 4 (hereinafter appropriately referred to as the second circumferential surface 4a) have different surface roughnesses, in other words, surface roughnesses. Specifically, the first circumferential surface 2a has a first surface roughness, and the second circumferential surface 4a has a second surface roughness that is larger than the first surface roughness. By setting the surface roughness of the second circumferential surface 4a to be larger than the surface roughness of the first circumferential surface 2a, the compound sheet 6 can be easily placed on the second circumferential surface 4a. In other words, the compound sheet 6 can be easily transferred to the second circumferential surface 4a. Thus, the conveying stability of the compound sheet 6 of the conveying device 1 can be improved.

[0026] The "surface roughness" in this embodiment refers to the arithmetic mean roughness Ra specified in JIS B 0601 2001. However, surface roughness is not limited to Ra and may also refer to other known indicators such as maximum height roughness Rz. In other words, for any of these roughness indicators, it is sufficient as long as the roughness of the second peripheral surface 4a is greater than the roughness of the first peripheral surface 2a.

[0027] As an example, the gap G between the first roller 2 and the second roller 4 is set to be smaller than the thickness of the composite sheet 6 supplied from the forming device 10. The size of the gap G in this embodiment is the distance between the first circumferential surface 2a and the second circumferential surface 4a at their closest approach. By setting this gap G, the first roller 2 and the second roller 4 can convey the composite sheet 6 while stretching it. In other words, the first roller 2 and the second roller 4 also function as stretching rollers.

[0028] In addition, in the present embodiment, the first roller 2 rotates at a first peripheral speed, and the second roller 4 rotates at a second peripheral speed greater than the first peripheral speed. More preferably, the second peripheral speed is faster than the first peripheral speed. By setting such a peripheral speed, the composite sheet 6 can also be extended. In addition, the extension of the composite sheet 6 can also be achieved by making the second surface roughness greater than the first surface roughness. The extension of the composite sheet 6 based on the first roller 2 and the second roller 4 can be achieved by at least one of the gap G, the peripheral speed difference and the surface roughness difference, and the composite sheet 6 can be made easier to extend by combining two or more. That is, the ductility of the composite sheet 6 can be improved.

[0029] Alternatively, a first roller 2 and a second roller 4 may be provided at the separate outlet of the storage section 12 in place of the pair of forming rollers 14. In this case, the dry electrode mixture 8 is directly supplied to the gap G between the first roller 2 and the second roller 4. The first roller 2 and the second roller 4 then compress the dry electrode mixture 8 into a sheet, forming the mixture sheet 6. In other words, the first roller 2 and the second roller 4 can also function as forming rollers.

[0030] The difference between the first surface roughness and the second surface roughness is preferably not less than 0.05 μm and not more than 2 μm. Thus, the ductility of the composite sheet 6 can be improved. In addition, the second surface roughness is preferably less than 1 / 5 of the gap G between the first roller 2 and the second roller 4. The second surface roughness in this case is the arithmetic mean roughness Ra. Thus, the ductility of the composite sheet 6 can be improved. In addition, when the first roller 2 and the second roller 4 also function as forming rollers, it is possible to suppress the occurrence of cracks and breakage in the composite sheet 6. That is, the formability of the composite sheet 6 can also be improved. In particular, the formability of the end portion of the composite sheet 6 in the width direction, that is, in the direction perpendicular to the conveying direction, can be improved. In addition, the formability of the composite sheet 6 when it is supplied to the gap between the first roller 2 and the second roller 4 is determined by whether cracks or breakage occur in the composite sheet 6 after passing through the gap between the two rollers.

[0031] The conveying device 1 of this embodiment includes a third roller 16 and a fourth roller 18 on the downstream side of the second roller 4. The third roller 16 and the fourth roller 18 function as conveying rollers in the same manner as the first roller 2 and the second roller 4. The fourth roller 18 is located downstream of the third roller 16 in the conveying direction of the composite sheet 6.

[0032] The second roller 4 and the third roller 16 are positioned so that their respective rotation axes are parallel to each other and are adjacent to each other at a predetermined interval. The compound sheet 6 is supported and conveyed by the second circumferential surface 4a and is fed into the gap between the second roller 4 and the third roller 16. The second roller 4 and the third roller 16 can convey the compound sheet 6 to the downstream side by sandwiching the compound sheet 6 between each other and rotating in opposite directions. The compound sheet 6 supported by the second circumferential surface 4a is handed over to the circumferential surface of the third roller 16 (hereinafter appropriately referred to as the third circumferential surface 16a), supported by the third circumferential surface 16a, and conveyed to the downstream side.

[0033] The third roller 16 and the fourth roller 18 are positioned so that their respective rotation axes are parallel to each other and are adjacent to each other at a predetermined interval. The compound sheet 6 is supported and conveyed by the third circumferential surface 16a and is fed into the gap between the third roller 16 and the fourth roller 18. The third roller 16 and the fourth roller 18 can convey the compound sheet 6 to the downstream side by sandwiching the compound sheet 6 between each other and rotating in opposite directions. The compound sheet 6 supported by the third circumferential surface 16a is handed over to the circumferential surface of the fourth roller 18 (hereinafter appropriately referred to as the fourth circumferential surface 18a), supported by the fourth circumferential surface 18a, and conveyed to the downstream side.

[0034] The third circumferential surface 16a preferably has a third surface roughness greater than the second surface roughness. This facilitates the transfer of the composite sheet 6 from the second circumferential surface 4a to the third circumferential surface 16a. Furthermore, the fourth circumferential surface 18a preferably has a fourth surface roughness greater than the third surface roughness. This facilitates the transfer of the composite sheet 6 from the third circumferential surface 16a to the fourth circumferential surface 18a. Specifically, the surface roughness of the circumferential surface increases as the conveying roller moves toward the downstream side, thereby improving the conveying stability of the composite sheet 6.

[0035] The third roller 16 and the fourth roller 18 can also function as spreading rollers. In this case, at least one of the gap G, the difference in peripheral speed, and the difference in surface roughness between the second roller 4 and the third roller 16 is set in the same manner as for the first roller 2 and the second roller 4, taking into account the thickness of the conveyed composite sheet 6, etc. Furthermore, at least one of the gap G, the difference in peripheral speed, and the difference in surface roughness between the third roller 16 and the fourth roller 18 is set in the same manner as for the first roller 2 and the second roller 4, taking into account the thickness of the conveyed composite sheet 6, etc.

[0036] also, Figure 1Although the first to fourth rollers 2 to 18 are shown as having the same diameter as each other, the diameters of the rollers may be different. Figure 2 Schematic diagram of a modified example of the conveying device 1. Figure 2 As shown, the first roller 2 has a first diameter D1, and the second roller 4 has a second diameter D2 that is greater than or equal to the first diameter D1. The second diameter D2 is preferably greater than or equal to the first diameter D1. Furthermore, the third roller 16 has a third diameter D3 that is greater than or equal to the second diameter D2, and preferably greater than or equal to the second diameter D2. Furthermore, the fourth roller 18 has a fourth diameter D4 that is greater than or equal to the third diameter D3, and preferably greater than or equal to the third diameter D3. In other words, in the conveying device 1 of the modified example, the diameters of the conveying rollers gradually increase as they move downstream.

[0037] This configuration can minimize the change in curvature of the composite sheet 6 that occurs when the composite sheet 6 is transferred from the circumferential surface of the upstream roller to the circumferential surface of the downstream roller. Consequently, the stress applied to the composite sheet 6 can be reduced, and damage to the composite sheet 6 can be suppressed. Consequently, the formability of the composite sheet 6 can be improved.

[0038] As another modified example, the conveying device 1 may include at least the first roller 2 and the second roller 4 as conveying rollers, and the third roller 16 and the fourth roller 18 may be omitted. Furthermore, the number of conveying rollers may be three or five or more. Furthermore, a conveying roller may be provided upstream of the first roller 2. In this case, the composite sheet 6, supported and conveyed by the first circumferential surface 2a, is fed into the gap between the first roller 2 and the second roller 4.

[0039] In addition, the stretching function may be imparted to all or only some of the conveying rollers. In addition, the conveying rollers may be arranged so that their respective axes are located on the same plane or on different planes. Figure 1 , the case where the composite sheet 6 is supplied from above the first roller 2 and the second roller 4 in the vertical direction is shown, but the composite sheet 6 may be supplied to the gap between the first roller 2 and the second roller 4 in the horizontal direction or in an oblique direction.

[0040] The composite sheet 6 conveyed by the conveying device 1 may also be subjected to a compression treatment. For example, a pair of pressure rollers are provided on the downstream side of the fourth roller 18. Then, the composite sheet 6 supported and conveyed by the fourth circumferential surface 18a is supplied to the gap between the pair of pressure rollers and compressed by the pair of pressure rollers. In addition, the composite sheet 6 may also be stacked on a sheet such as a collector foil. For example, a stacking roller for conveying a sheet is arranged at a position opposite to the fourth roller 18, and the composite sheet 6 supported by the fourth circumferential surface 18a is stacked on a sheet supported by the circumferential surface of the stacking roller. In addition, when the third roller 16 and the fourth roller 18 are omitted, a pressure roller and a stacking roller may also be arranged relative to the second roller 4. In addition, the pressure roller may be arranged on the upstream side of the stacking roller, and the stacking roller may also be arranged on the upstream side of the pressure roller.

[0041] As described above, the conveying device 1 of this embodiment includes a first roller 2 and a second roller 4 that sandwich and convey the composite sheet 6. The second roller 4, located downstream of the first roller 2, has a second circumferential surface 4a having a surface roughness greater than that of the first circumferential surface 2a of the first roller 2. By making the surface roughness of the downstream roller greater than that of the upstream roller, the transferability of the composite sheet 6 to the downstream roller can be improved. Consequently, the conveyance stability of the composite sheet 6 can be improved.

[0042] In particular, dry electrode mixture 8 has lower adhesion to the roller circumference than wet electrode mixtures, i.e., those containing more than 5% solvent by mass. Therefore, it is not easy to transfer the mixture sheet 6 passing through the gap between the first roller 2 and the second roller 4 to the bottom 2 circumferential surface 4a. Therefore, the conveying device 1 of this embodiment functions particularly effectively when the electrode mixture is dry. Furthermore, this embodiment can also improve the conveying stability of the mixture sheet 6 when the electrode mixture is wet.

[0043] The embodiments of the present disclosure have been described in detail above. The above embodiments are merely ways of showing specific examples of implementing the present disclosure. The contents of the embodiments do not limit the technical scope of the present disclosure, and various design changes such as changes, additions, and deletions of constituent elements can be made without departing from the scope of the idea of the present disclosure as defined in the claims. The new embodiment with the design changes has the respective effects of the combined embodiments and the deformations. In the above embodiments, the contents that can undergo such design changes are emphasized with marks such as "in this embodiment" and "in this embodiment", but the contents without such marks also allow design changes. Any combination of the constituent elements included in each embodiment is also valid as a mode of the present disclosure. The hatching marked on the cross section of the accompanying drawings does not limit the material of the objects marked with the hatching.

[0044] The embodiment can also be specified by the items described below.

[0045] [Item 1]

[0046] A conveying device (1) for a composite tablet (6),

[0047] The invention comprises a first roller (2) and a second roller (4), wherein the first roller (2) and the second roller (4) sandwich a dry electrode mixture (8) formed into a sheet-like mixture sheet (6) between each other and rotate to convey the mixture sheet (6);

[0048] The first peripheral surface (2a) of the first roller (2) has a first surface roughness;

[0049] The second peripheral surface (4a) of the second roller (4) has a second surface roughness greater than the first surface roughness;

[0050] The second roller (4) is located on the downstream side of the conveying direction of the compound sheet (6) relative to the first roller (2), and supports and conveys the compound sheet (6) passing through the gap between the first roller (2) and the second roller (4) with the second peripheral surface (2a).

[0051] [Item 2]

[0052] The conveying device (1) as described in item 1,

[0053] The second surface roughness is smaller than 1 / 5 of the gap (G) between the first roller (2) and the second roller (4).

[0054] [Item 3]

[0055] The conveying device (1) as described in item 1 or item 2,

[0056] The difference between the first surface roughness and the second surface roughness is 0.05 μm or more and 2 μm or less.

[0057] [Item 4]

[0058] The conveying device (1) as described in any one of items 1 to 3,

[0059] The first roller (2) rotates at a first peripheral speed;

[0060] The second roller (4) rotates at a second peripheral speed that is greater than the first peripheral speed.

[0061] [Item 5]

[0062] The conveying device (1) as described in any one of items 1 to 4,

[0063] The first roller (2) has a first diameter (D1);

[0064] The second roller (4) has a second diameter (D2) that is larger than the first diameter (D1).

[0065] Example

[0066] Hereinafter, examples of the present invention will be described. However, the examples are merely illustrative for the purpose of appropriately describing the present invention and are not intended to limit the present invention in any way.

[0067] (Example 1)

[0068] A dry electrode mixture is prepared by mixing a positive electrode active material, a conductive material, and PTFE as a binder. The mixing amount of the conductive material is 0.9 parts by mass relative to 100 parts by mass of the positive electrode active material. The mixing amount of the binder is 0.8 parts by mass relative to 100 parts by mass of the positive electrode active material. In addition, as a conveying device, a first roller having a first surface roughness (Ra) of 2 μm and a second roller having a second surface roughness (Ra) of 5 μm and a diameter smaller than that of the first roller are prepared. Therefore, the difference between the first surface roughness and the second surface roughness is 3 μm. In addition, the ratio of the second diameter to the first diameter is less than 1 (specifically, the first diameter is 100 mm and the second diameter is 70 mm).

[0069] Next, the two rollers are arranged in such a way that the second surface roughness becomes 1 / 4 of the gap between the first and second rollers. That is, the gap between the two rollers is set to 20 μm. Then, the first and second rollers are rotated in opposite directions to each other, and the dry electrode mixture is supplied to the gap between them. At this time, the second roller rotates at a lower speed than the first roller. Therefore, the ratio of the second peripheral speed to the first peripheral speed is less than 1 (specifically, the first peripheral speed is 5 m / min and the second peripheral speed is 4 m / min).

[0070] (Example 2)

[0071] The test was carried out in the same manner as in Example 1 except for the following points. As a difference from Example 1, the first surface roughness (Ra) was set to 9 μm and the second surface roughness (Ra) was set to 10 μm. Therefore, the difference between the first surface roughness and the second surface roughness was 1 μm. In addition, the ratio of the second diameter relative to the first diameter was set to 1 or more (specifically, the first diameter was 70 mm and the second diameter was 100 mm). In addition, the gap between the two rollers was set to 40 μm. Therefore, the second surface roughness was 1 / 4 of the gap between the first roller and the second roller. In addition, the ratio of the second peripheral speed relative to the first peripheral speed was set to 1 or more (specifically, the first peripheral speed was 5 m / min and the second peripheral speed was 6 m / min).

[0072] (Example 3)

[0073] The test was carried out in the same manner as in Example 1 except for the following points. As a difference from Example 1, the first surface roughness (Ra) was set to 0.5 μm and the second surface roughness (Ra) was set to 2.5 μm. Therefore, the difference between the first surface roughness and the second surface roughness was 2 μm. In addition, the second surface roughness was set to be less than 1 / 5 of the gap between the first roller and the second roller (specifically, the gap between the two rollers was 1500 μm). In addition, the ratio of the second peripheral speed to the first peripheral speed was set to more than 1 (specifically, the first peripheral speed was 5 m / min and the second peripheral speed was 6 m / min).

[0074] (Example 4)

[0075] The test was conducted in the same manner as in Example 1, except for the following points. As a difference from Example 1, the ratio of the second diameter to the first diameter was set to 1 or greater (specifically, the first diameter was 70 mm and the second diameter was 100 mm). Furthermore, the second surface roughness was set to less than 1 / 5 of the gap between the first and second rollers (specifically, the gap between the two rollers was 30 μm). Furthermore, the ratio of the second peripheral speed to the first peripheral speed was set to 1 or greater (specifically, the first peripheral speed was 5 m / min and the second peripheral speed was 5 m / min).

[0076] (Example 5)

[0077] The test was carried out in the same manner as in Example 1 except for the following points. As a difference from Example 1, the first surface roughness (Ra) was set to 0.5 μm and the second surface roughness (Ra) was set to 2.5 μm. Therefore, the difference between the first surface roughness and the second surface roughness was 2 μm. In addition, the ratio of the second diameter relative to the first diameter was set to be greater than 1 (specifically, the first diameter was 100 mm and the second diameter was 100 mm). In addition, the second surface roughness was set to be less than 1 / 5 of the gap between the first and second rollers (specifically, the gap between the two rollers was 500 μm).

[0078] (Example 6)

[0079] Except for the following points, the test is carried out in the same manner as in Example 1. As a difference from Example 1, the first surface roughness (Ra) is set to 0.50 μm and the second surface roughness (Ra) is set to 0.55 μm. Therefore, the difference between the first surface roughness and the second surface roughness is 0.05 μm. In addition, the ratio of the second diameter relative to the first diameter is set to more than 1 (specifically, the first diameter is 100 mm and the second diameter is 100 mm). In addition, the second surface roughness is set to less than 1 / 5 of the gap between the first roller and the second roller (specifically, the gap between the two rollers is 100 μm). In addition, the ratio of the second peripheral speed relative to the first peripheral speed is set to more than 1 (specifically, the first peripheral speed is 5 m / min and the second peripheral speed is 5 m / min).

[0080] (Example 7)

[0081] Except for the following points, the test is carried out in the same manner as in Example 1. As a difference from Example 1, the first surface roughness (Ra) is set to 0.5 μm and the second surface roughness (Ra) is set to 2.5 μm. Therefore, the difference between the first surface roughness and the second surface roughness is 2 μm. In addition, the ratio of the second diameter relative to the first diameter is set to more than 1 (specifically, the first diameter is 70 mm and the second diameter is 100 mm). In addition, the second surface roughness is set to less than 1 / 5 of the gap between the first roller and the second roller (specifically, the gap between the two rollers is 100 μm). In addition, the ratio of the second peripheral speed relative to the first peripheral speed is set to more than 1 (specifically, the first peripheral speed is 5 m / min and the second peripheral speed is 6 m / min).

[0082] (Comparative Example 1)

[0083] Except for the following points, the test is carried out in the same manner as in Example 1. As a difference from Example 1, the first surface roughness (Ra) is set to 0.005 μm, and the second surface roughness (Ra) is set to 0.005 μm. Therefore, the difference between the first surface roughness and the second surface roughness is 0 μm. In addition, the ratio of the second diameter relative to the first diameter is set to more than 1 (specifically, the first diameter is 70 mm and the second diameter is 100 mm). In addition, the second surface roughness is set to less than 1 / 5 of the gap between the first roller and the second roller (specifically, the gap between the two rollers is 30 μm). In addition, the ratio of the second peripheral speed relative to the first peripheral speed is set to more than 1 (specifically, the first peripheral speed is 5 m / min and the second peripheral speed is 6 m / min).

[0084] (Comparative Example 2)

[0085] Except for the following points, the test is carried out in the same manner as in Example 1. As a difference from Example 1, the first surface roughness (Ra) is set to 0.050 μm and the second surface roughness (Ra) is set to 0.4 μm. Therefore, the first surface roughness is 0.1 μm smaller than the second surface roughness. In addition, the ratio of the second diameter relative to the first diameter is set to more than 1 (specifically, the first diameter is 70 mm and the second diameter is 100 mm). In addition, the second surface roughness is set to less than 1 / 5 of the gap between the first roller and the second roller (specifically, the gap between the two rollers is 300 μm). In addition, the ratio of the second peripheral speed relative to the first peripheral speed is set to more than 1 (specifically, the first peripheral speed is 5 m / min and the second peripheral speed is 6 m / min).

[0086] The transferability of the composite sheet was visually evaluated for the conveying devices of each embodiment and each comparative example. In the evaluation of transferability, the case where the composite sheet was transferred to the second peripheral surface was evaluated as "A", and the case where it was not transferred was evaluated as "B". In addition, the ductility of the composite sheet was evaluated. In the evaluation of ductility, the case where the thickness of the composite sheet on the second peripheral surface was less than the gap between the first roller and the second roller was evaluated as "AA", the case where the thickness was equal to the gap was evaluated as "A", and the case where the fracture of the composite sheet was visually confirmed was evaluated as "B". The thickness of the composite sheet was the average thickness of the average value of the thickness at any 10 points. In addition, the formability of the composite sheet was visually evaluated on the second peripheral surface. In the evaluation of formability, the case where no cracks or damage were seen at the end of the composite sheet in the width direction was evaluated as "AA", the case where cracks or damage that were allowable as a composite sheet were seen was evaluated as "A", and the case where cracks or damage that were not allowable as a composite sheet were seen was evaluated as "B".

[0087] Figure 3 : is a diagram showing the conditions and evaluation results of the conveying devices of each embodiment and each comparative example. Figure 3 As shown, in Example 1, in which the second surface roughness is greater than the first surface roughness, the transferability is good. In contrast, in Comparative Example 1, in which the second surface roughness is equal to the first surface roughness, and Comparative Example 2, in which the second surface roughness is less than the first surface roughness, the composite sheet failed to transfer to the second roller. Thus, it was confirmed that by setting the second surface roughness to be greater than the first surface roughness, the transferability and conveying stability of the composite sheet can be improved. In addition, in Comparative Examples 1 and 2, since the composite sheet failed to transfer to the second roller, the ductility and formability could not be evaluated.

[0088] In addition, not only is the second surface roughness greater than the first surface roughness, but in Examples 6 and 7, in which the second surface roughness is less than 1 / 5 (<1 / 5) of the gap between the first and second rollers, the difference in surface roughness is greater than 0.05 μm and less than 2 μm, the second circumferential speed is greater than the first circumferential speed (1≧), and the second diameter is greater than the first diameter (1≧), improvements in ductility and formability can be seen compared to Example 1.

[0089] In addition, in Example 2, which differed from Examples 6 and 7 in that the second surface roughness was 1 / 5 or more (1 / 4) of the gap between the first and second rollers, ductility and formability were lower than those of Examples 6 and 7. Thus, it was confirmed that by setting the second surface roughness to less than 1 / 5 of the gap between the first and second rollers, the ductility and formability of the composite sheet can be improved.

[0090] In Example 3, which differs from Examples 6 and 7 in that the second diameter is smaller than the first diameter (<1), the moldability is lower than that of Examples 6 and 7. This confirms that the moldability of the composite sheet can be improved by setting the second diameter to be greater than the first diameter.

[0091] In addition, in Example 4, which differed from Examples 6 and 7 in that the difference in surface roughness deviated from the range of 0.05 μm to 2 μm, ductility decreased compared to Examples 6 and 7. This confirmed that the ductility of the composite sheet can be improved by setting the difference between the first surface roughness and the second surface roughness to 0.05 μm to 2 μm.

[0092] In Example 5, which differs from Examples 6 and 7 in that the second peripheral speed is less than the first peripheral speed (<1), the ductility is lower than that of Examples 6 and 7. This confirms that the ductility of the composite sheet can be improved by setting the second peripheral speed to be greater than the first peripheral speed.

[0093] [Industrial Applicability]

[0094] The present disclosure can be used in a delivery device for composite tablets.

[0095] [Explanation of Reference Numerals]

[0096] 1 conveying device, 2 first roller, 2a first peripheral surface, 4 second roller, 4a second peripheral surface, 6 compound sheet, 8 dry electrode compound.

Claims

1. A device for conveying a composite tablet, A first roller and a second roller are provided, wherein the first roller and the second roller convey the dry electrode mixture by sandwiching a mixture sheet formed into a sheet shape between the first roller and the second roller and rotating the mixture sheet; The first circumferential surface of the first roller has a first surface roughness; The second peripheral surface of the second roller has a second surface roughness greater than the first surface roughness; The second roller is located downstream of the first roller in the conveyance direction of the composite sheet, and supports the composite sheet passing through a gap between the first roller and the second roller with the second peripheral surface.

2. The conveying device according to claim 1, The second surface roughness is smaller than 1 / 5 of the gap between the first roller and the second roller.

3. The conveying device according to claim 1 or 2, The difference between the first surface roughness and the second surface roughness is not less than 0.05 μm and not more than 2 μm.

4. The conveying device according to claim 1 or 2, The first roller rotates at a first peripheral speed; The second roller rotates at a second peripheral speed that is greater than or equal to the first peripheral speed.

5. The conveying device according to claim 1 or 2, The first roller has a first diameter; The second roller has a second diameter that is larger than the first diameter.

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