Coating device
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO LTD
- Filing Date
- 2026-01-28
- Publication Date
- 2026-08-06
Smart Images
Figure JP2026002760_06082026_PF_FP_ABST
Abstract
Description
Coating device
[0001] The present disclosure relates to a coating device.
[0002] Conventionally, an electrode that is a plate-shaped or belt-shaped positive electrode or negative electrode constituting a secondary battery such as a lithium-ion secondary battery includes an electrode core and an electrode mixture layer formed on the surface of the electrode core. In some cases, the electrode mixture layer is formed on the surface of the electrode core via a protective layer.
[0003] In order to form an electrode mixture layer or a protective layer on the surface of the electrode core of such an electrode for a secondary battery, a coating device has been conventionally used. Patent Document 1 describes a coating device including a coating head that discharges a coating liquid from a discharge port at the tip of the coating head and applies the discharged coating liquid to a substrate.
[0004] In the coating device described in Patent Document 1, in the coating by the coating head, the coating head is rotatably held on a base table with the surface of the substrate as a reference portion, the tip spraying surface faces the surface of the substrate, and by the swing of the coating head due to the rise of the holding shaft which is the swing axis of the coating head, the distance between the discharge port at the tip surface of the coating head and the substrate can be adjusted.
[0005] Japanese Unexamined Patent Application Publication No. 2022-163357
[0006] However, in the coating machine described in Patent Document 1, when adjusting the coating gap which is the distance between the discharge port and the substrate, the entire coating head moves. Also, since the distance between the holding shaft and the discharge port becomes large, it is difficult to accurately adjust the coating gap by the swing of the coating head due to the rise of the holding shaft. Therefore, it is desired to realize a coating device that can adjust the coating gap, which is the distance between the substrate to be coated and the discharge port of the coating head, with high precision and easily.
[0007] The coating apparatus according to this disclosure comprises a coating head having a discharge port at its tip for discharging a coating liquid, and a substrate support part that supports a substrate facing the tip of the coating head, wherein the substrate support part includes a roller, the tip of the coating head faces a portion of the substrate arranged along the cylindrical outer surface of the roller, and the coating apparatus is equipped with an up-down adjustment mechanism that allows the vertical position of the coating head to be adjusted by operation.
[0008] According to the coating apparatus of this disclosure, the discharge port at the tip of the coating head is positioned opposite the substrate arranged along the cylindrical outer surface of the roller, and the vertical position of the coating head can be adjusted by an up-and-down adjustment mechanism. In this case, the larger the radius of curvature of the outer surface of the roller, the higher the accuracy of adjusting the coating gap by adjusting the vertical position of the coating head. Moreover, it is technically easy to increase the radius of curvature of the outer surface of the roller. As a result, the coating apparatus of this disclosure allows for high-precision and easy adjustment of the coating gap.
[0009] This is a perspective view of a coating apparatus according to an embodiment of the present disclosure. This is a view of the coating apparatus shown in Figure 1 from the coating head side. This is an enlarged view of part A in Figure 2. This is a view of the coating apparatus in Figure 1 from one axial side of the roller. This is an enlarged view of part B in Figure 4. This is an enlarged view of part C in Figure 5. This is a diagram corresponding to Figure 2 of a coating apparatus in another embodiment. This is an enlarged view of part D in Figure 7. This is a diagram corresponding to Figure 5 of the coating apparatus in Figure 7. This is an enlarged view of part E in Figure 9. This is a diagram corresponding to an enlarged view of the central part of Figure 10, which shows a reduced radius of curvature of the roller to explain the difference in coating gaps for the first and second discharge ports. This is a diagram corresponding to Figure 11, which shows the case when the coating gap is raised in order to change the relationship between the coating gaps for the first and second discharge ports. This is a diagram showing the relationship between the amount of rise of the coating head and the first coating gap for the first discharge port, the second coating gap for the second discharge port, and the increase in the difference between the first and second coating gaps (increase in coating gap difference).
[0010] The coating apparatus according to this disclosure will be described below with reference to the drawings. In the following description, an electrode will be formed by applying an electrode mixture slurry to an electrode core that constitutes an electrode for a secondary battery, but it can be applied to various configurations as long as the coating liquid is applied to the surface of the substrate.
[0011] Figures 1 to 6 show a coating apparatus 10 of an embodiment. The coating apparatus 10 is composed of a fixed base 11, a movable base 20, a coating head 30, a supply device 60 (Figure 4), a substrate support section 70, a vertical adjustment mechanism 80, and a horizontal adjustment mechanism 90. In Figure 1, the relationship between the coating head 30 and the roller 72 is such that the coating head 30 side is the front side Fr, the roller 72 side is the rear side Rr, the first horizontal direction (left-right direction) is indicated by X, the second horizontal direction (front-back direction) is indicated by Y, and the vertical direction is indicated by Z.
[0012] The fixed base 11 is connected by a connecting portion 13 that extends in the left-right direction X, between two side plates 12 that are separated in the left-right direction X. A movable base 20 is stretched across the upper side of the connecting portion 13 between the two side plates 12. The movable base 20 is supported so as to be movable in the front-rear direction Y along rails 100 provided on the upper surfaces of each side plate 12. Grooves that engage with the rails 100 are provided at both ends of the lower end of the movable base 20 in the left-right direction X. The movable base 20 is a roughly box-shaped structure that is elongated in the left-right direction X. The coating head 30, described later, is supported on the upper side of the movable base 20. As a result, the coating head 30 is supported on the fixed base 11 so as to be movable in the front-rear direction Y. The positional relationship of the movable base 20 in the front-rear direction Y with respect to the fixed base 11 can be adjusted by the lateral adjustment mechanism 90, described later.
[0013] The coating head 30 is supported on the upper side of the movable base 20 so as to be able to move in the vertical direction Z. A vertical adjustment mechanism 80, which will be described later, is provided between the coating head 30 and the movable base 20. The vertical adjustment mechanism 80 can be operated to adjust the vertical position of the coating head 30.
[0014] The coating head 30 applies the coating liquid to the surface of the substrate 110 (Figure 5). The substrate 110 is a long strip and has a configuration in which multiple electrode cores that form electrodes for a secondary battery are connected in the longitudinal and width directions of the substrate. The substrate 110 is a strip of cores before it is cut and separated into multiple electrode cores after the coating liquid has been applied and dried. The coating liquid is applied in layers to at least one side of the substrate 110 by the coating apparatus 10, either continuously or intermittently in the longitudinal direction. The coating liquid is an electrode mixture slurry that forms an electrode mixture.
[0015] When the base material 110 includes a positive electrode core that constitutes the positive electrode, the base material 110 can be, for example, a metal foil such as aluminum, or a film with the metal arranged on its surface. A suitable positive electrode core is a metal foil mainly composed of aluminum or an aluminum alloy. The thickness of the positive electrode core is, for example, 10 μm or more and 30 μm or less.
[0016] After the positive electrode mixture slurry is applied to the surface of the substrate 110 as a coating liquid, the coating film is dried and cut to a predetermined electrode size. Subsequently, the substrate 110 coated with the positive electrode mixture slurry is rolled with a roller to produce a positive electrode of a predetermined thickness. The positive electrode mixture slurry includes, for example, a positive electrode active material, a conductive agent, a binder, and a solvent such as N-methyl-2-pyrrolidone (NMP).
[0017] When the base material 110 includes a negative electrode core that constitutes the negative electrode, the base material 110 can be, for example, a metal foil such as copper, or a film with the metal arranged on its surface. A suitable negative electrode core is a metal foil mainly composed of copper or a copper alloy. The thickness of the negative electrode core is, for example, 40 μm or more and 100 μm or less.
[0018] After the negative electrode mixture slurry is applied to the surface of the substrate 110 as a coating liquid, the coating film is dried and cut to a predetermined electrode size. Subsequently, the substrate 110 coated with the negative electrode mixture slurry is rolled with a roller to produce a negative electrode of a predetermined thickness. The negative electrode mixture slurry includes, for example, a negative electrode active material, a binder, and water.
[0019] The coating liquid may be applied to one surface of the substrate 110 by the coating apparatus 10, and then applied to the other surface of the substrate 110 by the same coating apparatus.
[0020] The coating head 30 applies the coating liquid to the surface of the substrate 110. The coating liquid is supplied to the coating head 30 by a supply device 60, which will be described later. The coating head 30 has a supply port 31 (Figure 3) on its front side for supplying the coating liquid, and a discharge port 32 at its rear end for discharging the coating liquid. Inside the coating head 30, a manifold (not shown) is formed that connects the supply port 31 and the discharge port 32. The manifold temporarily stores the coating liquid.
[0021] The coating head 30 has a first block 33, a shim 35, and a second block 37 arranged in order from top to bottom, with the shim 35 sandwiched between the first and second blocks 33 and 37. The first block 33 is a long block shape with an upper recess (not shown) that is long in the longitudinal direction of the block formed on its lower surface. The second block 37 is a long block shape with a lower recess (not shown) that is long in the longitudinal direction of the block formed on its upper surface. The shim 35 is a roughly U-shaped plate material that surrounds three sides of the shim, excluding the middle part in the longitudinal direction of the end on the discharge port 32 side when viewed from above or below.
[0022] The shim 35 is interposed between the first block 33 and the second block 37, creating a gap between the front ends of each block 33 and 37 equal to the thickness of the shim 35. This gap forms the discharge port 32. With the first block 33 and the second block 37 connected, the upper recess, the lower recess, and the space created by the thickness of the shim 35 form a manifold (not shown) that is long in the longitudinal direction of the blocks.
[0023] As schematically shown in the block diagram in Figure 4, the supply device 60 supplies the coating liquid to the coating head 30 through the supply port 31. For example, the supply device 60 supplies the coating liquid stored in the tank to the supply port 31 through the coating liquid supply pipeline by driving a pump.
[0024] The base material support section 70 includes a bearing section 71 fixed to the upper portion of each side plate 12 of the fixed base 11, and a substantially cylindrical roller 72 whose shafts at both ends are rotatably supported by the two bearing sections 71. As a result, the base material support section 70 is supported by the fixed base 11. The roller 72 rotates in the direction of arrow α in Figure 5. The base material 110 is supported and conveyed along the cylindrical outer surface of the roller 72. As a result, the base material 110 moves in the direction of arrow β in Figure 5.
[0025] The roller 72 supports the substrate 110 facing the tip of the coating head 30. Specifically, the tip of the coating head 30 faces the portion of the substrate 110 that is positioned along the front portion of the cylindrical outer surface of the roller 72, with a small gap in between.
[0026] The vertical adjustment mechanism 80 includes one-side adjustment section 81 and the other-side adjustment section 82, which are provided on both the left and right sides. As shown representatively by the adjustment section 81 in Figure 3, each adjustment section 81, 82 includes an upper inclined section 83, a lower inclined section 85, and a first rotating shaft 87, and the vertical position Z of the coating head 30 can be adjusted by operation. Each upper inclined section 83 is provided so as to protrude downward from the left-right end of the lower surface of the second block 37 of the coating head 30. Each lower inclined section 85 is a block shape positioned above the movable base 20, opposite to the lower inclined section 83, and is movable only in the left-right direction X, which is a first lateral direction perpendicular to the vertical direction Z. Each first rotating shaft 87 is inserted in the left-right direction X into the lower inclined section 85 of the corresponding adjustment section 81, 82.
[0027] Each upper inclined portion 83 has an upper inclined surface 84 on its lower surface that is inclined with respect to the vertical Z direction and the left-right X direction. Each lower inclined portion 85 has a lower inclined surface 86 on its upper surface that matches the upper inclined surface 84 of the opposing upper inclined portion 83 and is slidable relative to the upper inclined surface 84. Each lower inclined portion 85 has a screw hole (not shown) that penetrates in the left-right X direction.
[0028] Each first rotating shaft 87 has a threaded portion (not shown) that engages with a threaded hole in the corresponding lower inclined portion 85 of the adjustment portion 81, 82. The first rotating shaft 87 may be formed by a screw having a hexagonal head 88. Thus, the vertical adjustment mechanism 80 is configured to move each lower inclined portion 85 in the left-right direction X by rotation caused by the operation of each first rotating shaft 87, and to move the coating head 30 in the vertical direction Z by sliding between the lower inclined surface 86 and the upper inclined surface 84.
[0029] It is preferable that the direction in which the upper inclined surface 84 of each upper inclined portion 83 inclins with respect to the left-right direction X is opposite for the two left and right adjustment portions 81 and 82. The inclination direction of the upper inclined surface 84 of each of the left and right upper inclined portions 83 may be the opposite direction to that in the example shown in Figures 2 and 3.
[0030] As shown in Figure 4, the lateral adjustment mechanism 90 is provided between the fixed base 11 and the movable base 20, and is capable of adjusting the positional relationship of the movable base 20 with respect to the fixed base 11 in the front-rear direction Y. The lateral adjustment mechanism 90 includes drive units 91 and 92, a moving member 96, and a second rotation shaft 98.
[0031] Each drive unit 91, 92 includes a first fixing plate 93 that protrudes in the left-right direction X from the outer surface of each side plate 12 of the fixed base 11 and extends upward; an actuator 94 with a case 95 fixed at two positions aligned vertically on the front surface of the first fixing plate 93; and second fixing plates 21 that protrude from the outer surface of both ends of the movable base 20 in the left-right direction. Each second fixing plate 21 faces the corresponding first fixing plate 93 on both the left and right sides in the front-rear direction Y.
[0032] Each actuator 94 has rods 94a and 95a that protrude from the front end of the case 95, pass through the first fixing plate 93, protrude forward, and have their tips fixed to the second fixing plate 21. The actuators 94 are actuators that can switch the length of the protruding portion of the rods by switching the air pressure, and by switching the intake and discharge of air pressure by turning the electromagnetic switching valve on and off, the extension and retraction of the protruding portions of the rods 94a and 95a that protrude from the case can be switched. For example, when the electromagnetic switching valve is not energized, the protruding portions of the rods 94a and 95a become longer in the left and right directions, and when the electromagnetic switching valve is energized, the protruding portions of the rods 94a and 95a retract into the case 95 and the protruding portions become shorter. As a result, the drive units 91 and 92 move the movable base 20 and the coating head 30 supported on the upper side of the movable base 20 to the rear side by switching the energization. As a result, the movable base 20 is moved in the front-rear direction Y relative to the fixed base 11 so that the tip of the coating head 30 is closer to the substrate 110.
[0033] The solenoid valve may be configured such that the protruding portions of the rods 94a and 95a become longer when energized and shorter when de-energized. The actuator 94 is not limited to a configuration in which the protruding portion of the rod can be extended or retracted by switching air pressure, but may also be configured as an electromagnetic actuator in which the length of the protruding portion of the rod can be switched by switching the energization of a coil located inside.
[0034] The movable member 96 is provided between the fixed base 11 and the movable base 20 and is movable only in the vertical direction Z. The movable member 96 is block-shaped and has a first inclined surface 97 on its front side that is inclined with respect to the vertical direction Z and the front-rear direction Y. The first inclined surface 97 is inclined towards the rear as it moves downward. On the rear surface of the second fixed plate 21 of the movable base 20, an inclined portion 22 is provided, which has a second inclined surface 23 on the rear surface that is on the fixed base 11 side in the front-rear direction Y. The second inclined surface 23 is inclined with respect to the vertical direction Z and the front-rear direction Y so as to coincide with the first inclined surface 97 and can be pressed against the first inclined surface 97. The movable member 96 has a screw hole (not shown) that penetrates in the vertical direction Z.
[0035] The second rotating shaft 98 has a threaded portion (not shown) that is screw-engaged into a screw hole in the movable member 96, and the threaded portion penetrates the movable member 96 from top to bottom while screw-engaging into the screw hole. The portion of the second rotating shaft 98 that protrudes downward from the lower end of the movable member 96 is inserted into a cylindrical portion 14 that is fixed to the fixed base 11 so as to protrude upward, and is screw-engaged into a screw hole provided in the cylindrical portion 14. As a result, the movement of the second rotating shaft 98 is restricted in the vertical direction Z.
[0036] The second rotating shaft 98 may be formed by a screw having a hexagonal head 99. The coating apparatus 10 moves each movable member 96 vertically by rotation caused by operating each second rotating shaft 98. As a result, the lateral adjustment mechanism 90 is configured such that the first inclined surface 97 and the second inclined surface 23 slide against each other due to rotation caused by operating the second rotating shaft 98, allowing the movable base 20 to move in both the left and right directions. Therefore, the positional relationship between the movable base 20 and the coating head 30 supported on the movable base 20 and the fixed base 11 in the front-rear direction Y can be adjusted.
[0037] In the coating apparatus 10 of this embodiment, the discharge port at the tip of the coating head 30 is positioned opposite the substrate 110 arranged along the cylindrical outer surface of the roller 72, and the vertical Z position of the coating head 30 can be adjusted by the vertical adjustment mechanism 80. At this time, the larger the radius of curvature of the outer surface of the roller 72, the higher the accuracy of adjusting the coating gap, which is the distance between the opening end of the discharge port 32 and the substrate 110 to be coated, by adjusting the vertical position of the coating head 30. Moreover, it is technically easy to increase the radius of curvature of the outer surface of the roller 72. As a result, the coating apparatus 10 of this embodiment allows for high-precision and easy adjustment of the coating gap.
[0038] Furthermore, according to this example, the vertical adjustment mechanism 80 includes an upper inclined portion 83 provided on the coating head 30 and having an upper inclined surface 84, a lower inclined portion 85 having a lower inclined surface 86 that is slidable with respect to the upper inclined surface 84 and is movable only in the left-right direction X, and a first rotating shaft 87 having a screw portion that engages with a screw hole in the lower inclined portion 85. In addition, the lower inclined portion 85 is moved in the left-right direction X by rotation by operating the first rotating shaft 87, and the coating head 30 is moved in the vertical direction Z by sliding between the lower inclined surface 86 and the upper inclined surface 84. As a result, the vertical Z position of the coating head 30 can be easily adjusted simply by rotating the first rotating shaft 87, so that the coating gap can be adjusted with high precision and more easily.
[0039] Figures 7 to 12 show a coating apparatus 10a of another embodiment. In this example, the coating liquid discharged from the coating head 30a constitutes two layers applied to the surface of the substrate 110, and consists of a first coating liquid and a second coating liquid with a different composition from the first coating liquid. The first coating liquid is an electrode mixture slurry, similar to the coating liquids in the configurations of Figures 1 to 6, and is used to form the upper layer of the two layers. The second coating liquid is a protective layer slurry and is used to form the lower layer of the two layers.
[0040] The protective layer is provided, for example, on the surface of the electrode core, specifically on the end where the electrode mixture layer is not formed and on the portion continuous from that end between the electrode mixture layer and the electrode core. The protective layer covers the surface of the electrode core where the electrode mixture layer is not formed, thereby suppressing internal short circuits caused by contact between different electrodes. The protective layer includes, for example, inorganic particles and a binder, which are insulating materials. By being placed between the electrode core and the electrode mixture layer, the protective layer can also improve the adhesion between the electrode core and the electrode mixture layer and suppress peeling of the electrode mixture layer from the electrode core.
[0041] The coating head 30a includes a first discharge port 38 and a second discharge port 39 as discharge ports. Specifically, the coating head 30a sandwiches the intermediate block 111 between the first block 33a and the second block 37 via shims 35 arranged on both the upper and lower surfaces of the intermediate block 111.
[0042] As shown in FIG. 9, the intermediate block 111 is a solid rectangular parallelepiped having a rectangular side surface with substantially the same vertical length at the rear end and the front end. In this example, an upper concave portion (not shown) provided on the lower surface of the first block 33a and a lower concave portion provided on the upper surface of the second block 37 are blocked by the intermediate block 111 and do not communicate with each other. The upper concave portion constitutes an upper manifold (not shown), and the lower concave portion constitutes a lower manifold. A first discharge port 38 that communicates with the upper manifold and discharges the first coating liquid is provided at a portion sandwiched between the front end opening of the upper shim 35, the first block 33a, and the intermediate block 111. A supply port 34 (FIG. 8) provided on the front surface of the first block 33a communicates with the upper manifold.
[0043] A second discharge port 39 that communicates with the lower manifold and discharges the second coating liquid is provided at a portion sandwiched between the front end opening of the lower shim 35, the second block 37, and the intermediate block 111. Thereby, the second discharge port 39 is provided at a position different from the first discharge port 38 in the vertical direction Z.
[0044] The electrode binder slurry, which is the first coating liquid, is supplied from the supply port 34 on the front surface of the first block 33a into the first block 33a. After the supplied electrode binder slurry is stored in the upper manifold, the electrode binder slurry is discharged from the first discharge port 38.
[0045] The protective layer slurry, which is the second coating liquid, is supplied from the supply port 31 on the front surface of the second block 37 into the second block 37. After the supplied protective layer slurry is stored in the lower manifold, the protective layer slurry is discharged from the second discharge port 39.
[0046] In this example, of the base material 110, the first discharge port 38 and the second discharge port 39 at the tip of the coating head 30a face each other through minute gaps at portions arranged along the front side portion of the cylindrical outer peripheral surface of the roller 72.
[0047] The configuration in this example is similar to that in Figures 1 to 6, and includes an up-down adjustment mechanism 80 and a lateral adjustment mechanism 90. In this configuration, the up-down adjustment mechanism 80 and the lateral adjustment mechanism 90 allow for adjustment of the first gap, which is the distance between the surface of the substrate 110 and the first discharge port 38 at the tip of the coating head 30a, and the second gap, which is the distance between the surface of the coating head 30a and the second discharge port 39 at the tip of the coating head 30a, respectively.
[0048] For example, as shown in Figure 11, the opening ends of the first discharge port 38 and the second discharge port 39 are located at the same position in the front-rear direction Y. In Figure 11, the radius of curvature of the cylindrical outer surface of the roller 72 is shown smaller than it actually is in order to make the difference in the coating gap for the first discharge port 38 and the second discharge port 39 easier to understand.
[0049] On the other hand, because the base material 110 follows the cylindrical outer surface of the roller 72, the positions in the front-rear direction Y of the base material 110 facing the first discharge port 38 and the position of the base material 110 facing the second discharge port 39 are different, depending on the curvature of the cylindrical outer surface. For example, the lower end of the opening of the second discharge port 39 faces the position of the base material 110 that coincides with the foremost position P1 in the front-rear direction Y of the cylindrical outer surface of the roller 72. On the other hand, the lower end of the opening of the first discharge port 38 faces the position of the base material 110 that coincides with position P3, which is above position P1 on the cylindrical outer surface of the roller 72 and behind position P1. As a result, the first distance between the surface of the base material 110 and the opening of the first discharge port 38 (the distance between positions P3 and P4 in Figure 11) and the second distance between the surface of the base material 110 and the opening of the second discharge port 39 (the distance between positions P1 and P2 in Figure 11) are of different magnitudes. At this time, the vertical Z position of the position where each discharge port 38, 39 and the base material 110 face each other can be easily changed by operating the first rotation shaft 87 of the vertical adjustment mechanism 80. This makes it possible to adjust the first and second intervals with high precision and ease.
[0050] Furthermore, with the configuration of this example, by adjusting the vertical adjustment mechanism 80 and the horizontal adjustment mechanism 90, the interval of the first interval and the second interval can be changed with higher precision while keeping one of them the same.
[0051] For example, in Figure 12, the coating head 30a is raised so that the position where the lower end of the opening of the second discharge port 39 of the coating head 30a faces the substrate 110 is a position P1a that is higher than position P1. The same position as position P1 of the roller 72 in Figure 11 is Pb in Figure 12.
[0052] As shown in Figure 12, if the coating head 30a is raised from the state in Figure 11, not only the first interval for the first discharge port 38 but also the second interval for the second discharge port 39 will increase. Therefore, the size of the second interval is made the same in Figure 11 and Figure 12 by operating the lateral adjustment mechanism 90. Even in this case, the first interval is larger in the state in Figure 12 than in the state in Figure 11. Therefore, while the second interval, which is one of the first and second intervals, is made the same, the first interval, which is the other interval, can be changed with higher precision. The above describes the case where the second interval is made the same, but for example, in the state in Figure 11, the lower end of the opening end of the first discharge port 38 is positioned opposite position P1, and from that state, the coating head 38a is lowered, and the Y position of the coating head 30a in the front-rear direction is adjusted with the lateral adjustment mechanism 90. This makes it possible to change the second interval with high precision, such as increasing the second interval for the second discharge port 39 while keeping the first interval for the first discharge port 38 the same.
[0053] Therefore, according to this example, the thickness of each different coating solution can be adjusted independently. Furthermore, this eliminates the need for cumbersome work such as preparing multiple types of intermediate blocks 111 with different vertical thicknesses to adjust the thickness of different coating solutions.
[0054] The difference between the second interval T2, which corresponds to the gap between the lower and upper layers of the mixture, and the first interval T1, which corresponds to the gap between the upper and lower layers of the mixture, (T1 - T2), is given by the following equation (1): (T1 - T2) = R - (R ２ - (H + t1 + h) ２ ) （１／２）... (1) Here, R is the radius of curvature of the cylindrical outer surface of the roller 72, H is the amount the coating head 30a rises, t1 is the vertical height of the opening end of the second discharge port 39, and h is the vertical height Z at the rear end, which is the tip of the intermediate block 111.
[0055] Figure 13 shows, in this embodiment, the relationship between the amount of upward movement of the coating head, the first interval T1 as the first coating gap for the first discharge port 38, the second interval T2 as the second coating gap for the second discharge port 39, and the increase in the difference between the first and second intervals T1 and T2 (T1-T2) (increase in coating gap difference).
[0056] In Figure 13, the solid line a represents the first interval T1, the dashed line b represents the second interval T2, and the dashed line c represents the increase in the coating gap difference (T1-T2). As shown in Figure 13, the greater the amount the coating head rises, the greater the first interval T1 and the second interval T2 become, but the amount the first interval T1 rises is greater than the amount the second interval T2 rises. Therefore, the greater the amount the coating head rises, the greater the increase in the coating gap difference. As a result, by setting an appropriate vertical Z position of the coating head 38a, any amount of increase in the coating gap difference can be set. Furthermore, with the configuration of this example, the film thickness ratio of multiple coating layers can be easily adjusted arbitrarily using the same coating apparatus 10a. In this example, the other configurations and operations are the same as those in Figures 1 to 6.
[0057] In the configurations of the above examples, the first lateral direction for tilting the upper inclined surface of the upper inclined part and the lower inclined surface of the lower inclined part that constitute the vertical adjustment mechanism 80 is not limited to the left-right direction X, but can also be the front-back direction Y, i.e., the same direction as the second lateral direction adjusted by the lateral adjustment mechanism 90. Also, the number of adjustment parts of the vertical adjustment mechanism 80 is not limited to two (left and right), but can be any number, such as one or three or more.
[0058] Furthermore, the number of outlets provided on the coating head is not limited to one or two; depending on the number of layers of coating liquids with three or more different compositions, the number of outlets provided on the coating head can be any number of three or more.
[0059] This disclosure is further described by the following embodiments. Configuration 1: A coating apparatus comprising: a coating head having a discharge port at its tip for discharging a coating liquid; and a substrate support portion for supporting a substrate facing the tip of the coating head, wherein the substrate support portion includes a roller, the tip of the coating head faces a portion of the substrate arranged along the cylindrical outer surface of the roller, and the coating apparatus comprises an up-down adjustment mechanism that allows the vertical position of the coating head to be adjusted by operation. Configuration 2: The coating apparatus according to Configuration 1, wherein the vertical adjustment mechanism is provided on the coating head and includes an upper inclined portion having an upper inclined surface inclined with respect to the vertical direction and a first lateral direction, a lower inclined portion having a lower inclined surface that matches the upper inclined surface and is slidable with respect to the upper inclined surface, and is movable only in the first lateral direction, and a first rotating shaft having a screw portion that engages with a screw hole in the lower inclined portion, and the lower inclined portion is moved in the first lateral direction by rotation by operation of the first rotating shaft, and the coating head is moved in the vertical direction by sliding between the lower inclined surface and the upper inclined surface. Configuration 3: The coating apparatus according to Configuration 1 or Configuration 2, wherein the coating liquid includes a first coating liquid and a second coating liquid having a different composition from the first coating liquid, and the discharge port includes a first discharge port for discharging the first coating liquid and a second discharge port provided at a different position in the vertical direction from the first discharge port for discharging the second coating liquid. Configuration 4: The coating apparatus according to Configuration 3, further comprising a lateral adjustment mechanism capable of adjusting the distance between the surface of the substrate and the first and second discharge ports at the tip of the coating head. Configuration 5: The coating apparatus according to Configuration 4, wherein the lateral adjustment mechanism is provided between a fixed base supporting the substrate support and a movable base on which the vertical adjustment mechanism and the coating head are located on the upper side, and is capable of adjusting the positional relationship of the movable base with respect to the fixed base in a second lateral direction perpendicular to the axial direction of the roller.Configuration 6: The coating apparatus according to Configuration 5, wherein the lateral adjustment mechanism comprises a drive unit that moves the movable table in the second lateral direction relative to the fixed table so that the coating head approaches the substrate, a movable member provided between the fixed table and the movable table and movable only in the vertical direction, and a second rotating shaft having a screw portion that engages with a screw hole provided in the vertical direction of the movable member, and a second inclined surface provided on the side surface of the movable table side of the movable member and inclined in the vertical direction, can be pressed against a second inclined surface that is inclined in the vertical direction and the second lateral direction so as to match the first inclined surface, and the movable table is configured to move in both the second lateral directions by rotation by operation of the second rotating shaft. Configuration 7: The coating apparatus according to any one of Configurations 1 to 6, wherein the substrate is a strip-shaped core body before it is cut and separated into a plurality of electrode core bodies that form electrodes for a secondary battery.
[0060] 10, 10a Coating device, 11 Fixed base, 12 Side plate, 13 Connecting part, 14 Cylinder part, 20 Movable base, 21 Second fixed plate, 22 Inclined part, 23 Second inclined surface, 30, 30a Coating head, 31 Supply port, 32 Discharge port, 33, 33a First block, 34 Supply port, 35 Shim, 37 Second block, 38 First discharge port, 39 Second discharge port, 60 Supply device, 70 Substrate support part, 71 Bearing part, 72 Roller, 80 Up / down adjustment mechanism, 81 One-side adjustment part, 82 Other-side adjustment part, 83 Upper inclined part, 84 Upper inclined surface, 85 Lower inclined part, 86 Lower inclined surface, 87 First rotating shaft, 88 Head, 90 Lateral adjustment mechanism, 91, 92 Drive unit, 93 First fixed plate, 94 Actuator, 95 Case, 96 Moving member, 97 First inclined surface, 98 Second rotation axis, 99 Head, 100 Rail, 110 Base material, 111 Intermediate block.
Claims
1. A coating apparatus comprising: a coating head having a discharge port at its tip for discharging a coating liquid; and a substrate support portion for supporting a substrate opposite the tip of the coating head, wherein the substrate support portion includes a roller, the tip of the coating head faces a portion of the substrate arranged along the cylindrical outer surface of the roller, and the apparatus includes an up-down adjustment mechanism that allows the vertical position of the coating head to be adjusted by operation.
2. The coating apparatus according to claim 1, wherein the vertical adjustment mechanism is provided on the coating head and includes an upper inclined portion having an upper inclined surface inclined with respect to the vertical direction and a first lateral direction, a lower inclined portion having a lower inclined surface that matches the upper inclined surface and is slidable with respect to the upper inclined surface, and is movable only in the first lateral direction, and a first rotating shaft having a screw portion that engages with a screw hole in the lower inclined portion, and is configured such that rotation by operation of the first rotating shaft moves the lower inclined portion in the first lateral direction, and sliding between the lower inclined surface and the upper inclined surface moves the coating head in the vertical direction.
3. The coating apparatus according to claim 1, wherein the coating liquid comprises a first coating liquid and a second coating liquid having a different composition from the first coating liquid, and the discharge port comprises a first discharge port for discharging the first coating liquid and a second discharge port provided at a different position vertically from the first discharge port for discharging the second coating liquid.
4. The coating apparatus according to claim 3, further comprising a lateral adjustment mechanism capable of adjusting the distance between the surface of the substrate and the first and second discharge ports at the tip of the coating head.
5. The coating apparatus according to claim 4, wherein the lateral adjustment mechanism is provided between a fixed base supporting the substrate support and a movable base on which the vertical adjustment mechanism and the coating head are located on the upper side, and is capable of adjusting the positional relationship of the movable base with respect to the fixed base in a second lateral direction perpendicular to the axial direction of the roller.
6. The coating apparatus according to claim 5, wherein the lateral adjustment mechanism comprises a drive unit that moves the movable table in the second lateral direction relative to the fixed table so that the coating head approaches the substrate; a movable member provided between the fixed table and the movable table and movable only in the vertical direction; and a second rotating shaft having a screw portion that engages with a screw hole provided in the vertical direction of the movable member, wherein a second inclined surface, inclined in the vertical direction and the second lateral direction, can be pressed against a first inclined surface inclined in the vertical direction, which is provided on the side surface of the movable member on the movable table side and is inclined in the vertical direction, so as to match the first inclined surface, and the movable table is configured to move in both the second lateral directions by rotation by operation of the second rotating shaft.
7. The coating apparatus according to claim 1, wherein the substrate is a strip-shaped core before it is cut and separated into a plurality of electrode cores that form electrodes for a secondary battery.