Conveying device and meandering correction method

Abstract

According to the present invention, a flotation roller (20a) uses a force that acts on a conveyed workpiece (W) without making contact in order to support the workpiece (W) in a non-contact manner. The flotation roller (20a) has a tubular shape extending in the width direction (B) of the workpiece (W), and at least a surface thereof facing the workpiece (W) is formed from a circumferential surface. A driving unit (20f) rotates the flotation roller (20a) in the yaw direction. Among the holding angles of the workpiece supported in a non-contact manner by the flotation roller, the holding angle of the inside from a topmost point and the holding angle of the outside from the topmost point are configured to be different angles.

Description

[Technical Field]

[0001] The present disclosure relates to a conveying device and a meandering correction method. [Background technology]

[0002] In recent years, progress has been made in the development of lithium metal secondary batteries, which use lithium metal for the anode. Lithium metal secondary batteries have a higher energy density than lithium-ion secondary batteries, and the theoretical capacity of lithium metal anodes is extremely large, approximately 10 times that of conventional graphite anodes. Recent developments have led to progress in addressing the issue of lithium metal dendrites, which was a problem with lithium metal secondary batteries, and lithium metal secondary batteries are expected to become more widespread.

[0003] One method for forming the negative electrode of a lithium metal secondary battery involves laminating lithium foil to a metal foil (e.g., copper foil) that serves as the base material. Lithium foil that has been rolled to a thickness of approximately 5 to 10 μm is prone to breaking, so care must be taken when transporting it. Other methods include transporting the lithium foil sandwiched between films (e.g., PP films), or using a floating roll to float and transport the lithium foil without contacting the roll. This specification focuses on the latter method, which does not require the film lamination and peeling processes.

[0004] In roll-to-roll transport, non-contact floating transport allows for low-tension transport with no contact resistance compared to contact transport. However, floating transport makes it easy for the workpiece (also called the web) to meander. Also, because the rolls do not come into contact with the workpiece, the mechanism for correcting meandering workpieces becomes complicated. In particular, lithium metal is the lightest of all metallic elements, making it easy for meandering to occur during floating transport.

[0005] Patent Document 1 discloses a conveying device that supports a strip in a non-contact manner by ejecting airflows from support pads onto the front and back of the strip being conveyed. In this conveying device, the support pads are tilted in the width direction of the strip to correct meandering of the strip. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2018-162121 Summary of the Invention [Problem to be solved by the invention]

[0007] In a method of correcting the meandering of a workpiece by tilting the floating roll in the width direction of the workpiece, when the meandering correction is performed, a difference occurs in the load applied to the right and left ends of the workpiece in the width direction, causing the part of the workpiece near where it passes through the floating roll to twist, making the workpiece more likely to tear in the width direction.

[0008] The present disclosure has been made in consideration of these circumstances, and its purpose is to provide a technology that realizes meandering correction with a low risk of breakage of a workpiece being levitated and transported. [Means for solving the problem]

[0009] In order to solve the above problems, a conveying device according to one aspect of the present disclosure includes a floating roll that supports a conveyed workpiece in a non-contact manner by utilizing a force that acts on the workpiece in a non-contact manner, the floating roll having a cylindrical shape extending in the width direction of the workpiece and at least a surface facing the workpiece formed by a circumferential surface, and a drive unit that rotates the floating roll in a yaw direction. Of the wrap angles of the workpiece supported in a non-contact manner by the floating roll, the wrap angle from the highest point on the entry side and the wrap angle from the highest point on the exit side are set to different angles.

[0010] Any combination of the above components, and conversion of the expression of the present disclosure into a method, device, system, etc., are also valid aspects of the present disclosure. [Effects of the Invention]

[0011] According to the present disclosure, it is possible to achieve meandering correction with a low risk of breakage of the workpiece being levitated and transported. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a side view schematically illustrating a transport device according to an embodiment. [Figure 2] 2 is a plan view schematically showing how the conveying device shown in FIG. 1 conveys a workpiece. FIG. [Figure 3] FIG. 1 is a side view schematically showing an example of a non-contact support roll designed such that the wrap angle on the inlet side is larger than the wrap angle on the outlet side. [Figure 4] 4A to 4C are diagrams for explaining meandering correction control using non-contact support rolls designed with an inlet wrap angle larger than the outlet wrap angle. [Figure 5] FIG. 1 is a side view schematically showing an example of a non-contact support roll designed such that the wrap angle on the inlet side is smaller than the wrap angle on the outlet side. [Figure 6] 6A to 6C are diagrams for explaining meandering correction control using non-contact support rolls designed so that the wrap angle on the inlet side is smaller than the wrap angle on the outlet side. [Figure 7] 7(A) and 7(B) are side views that schematically show an example of a non-contact support roll designed so that the wrap angle on the inlet side and the wrap angle on the outlet side are equal. [Figure 8] 8A to 8C are diagrams for explaining meandering correction control according to a comparative example. DETAILED DESCRIPTION OF THE INVENTION

[0013] The present disclosure will be described below with reference to the drawings based on preferred embodiments. The embodiments are illustrative and do not limit the present disclosure, and all features and combinations thereof described in the embodiments are not necessarily essential to the present disclosure. Identical or equivalent components, parts, and processes shown in each drawing are designated by the same reference numerals, and redundant description will be omitted where appropriate. The scale and shape of each part shown in each drawing are set for convenience to facilitate explanation and should not be interpreted as limiting unless otherwise specified. Furthermore, when terms such as "first" and "second" are used in this specification or claims, unless otherwise specified, these terms do not indicate any order or importance, but are intended to distinguish one configuration from another. Furthermore, some components that are not important for explaining the embodiments are omitted from each drawing.

[0014] 1 is a side view schematically illustrating a conveying device 1 according to an embodiment. The conveying device 1 is a roll-to-roll type conveying device, and includes an unwinding device 10, a floating roll device 20, an edge sensor 30, a winding device 40, and a control device 50.

[0015] The unwinding device 10 is located at the start of the conveying line, holds the workpiece W to be conveyed in a rolled state, and sends the workpiece W downstream of the conveying line. The winding device 40 is located at the end of the conveying line, and collects the conveyed workpiece W in a rolled state. The unwinding device 10 and the winding device 40 each have a servo motor (not shown), which can control the rotation speed and rotation torque of the roll. The unwinding speed of the unwinding device 10 and the winding speed of the winding device 40 are set to basically the same speed.

[0016] In this embodiment, the workpiece W is assumed to be lithium foil to be used as the negative electrode plate of a lithium metal secondary battery. The lithium foil to be transported in this embodiment is rolled to a thickness of approximately 5 to 10 μm, and there is a risk of it breaking even when even a small amount of tension is applied. Furthermore, because lithium has the property of easily adhering to metals, when using guide rolls made of metal (for example, aluminum), tension on the guide rolls is likely to increase. Therefore, in this embodiment, a floating roll device 20 is used that can transport the workpiece W without contact.

[0017] The floating roll device 20 is disposed on the conveying line between the unwinding device 10 and the winding device 40. Although not shown in Fig. 1, a tension control mechanism (for example, a dancer roll) for controlling the tension applied to the workpiece W to a constant value may be disposed on the conveying line between the unwinding device 10 and the floating roll device 20.

[0018] The floating roll device 20 supports the transported workpiece W in a non-contact manner. The floating roll device 20 has a non-contact support roll 20a, a support arm 20b, a rotating base 20c, a rotating shaft 20d, a fixed base 20e, and a motor 20f.

[0019] The non-contact support roll 20a is a cylinder extending in the width direction B of the workpiece W, and supports the workpiece W in a non-contact manner by blowing a fluid from its outer circumferential surface. In this embodiment, air is assumed as the blown fluid, but other gases such as nitrogen may also be used. The radial cross-sectional shape of the non-contact support roll 20a does not have to be a full circle or a full ellipse, but may be a semicircle or semi-ellipse. In these cases, the cross-sectional shape of the side that does not form the arc is formed into a rectangle. The non-contact support roll 20a does not rotate, and is installed so that the outer circumferential surface formed by a semicircle or semi-ellipse faces the workpiece W. The radial cross-sectional shape of the non-contact support roll 20a may be a sector (for example, a sector with a central angle of 90 degrees).

[0020] The non-contact support roll 20a may be, for example, a known air turn bar. The outer periphery of the air turn bar is covered with a thin metal plate (e.g., aluminum or stainless steel). The thin metal plate may be, for example, a punched screen with a large number of discharge holes. Note that instead of a punched screen, a porous material such as a thin plate or metal made of a porous foam, a porous thin plate made of sintered metal, or a mesh metal plate may be used.

[0021] Instead of drilling multiple holes in the metal sheet, multiple slits extending in the extension direction of the non-contact support roll 20a may be formed at predetermined intervals in the radial direction.Furthermore, multiple wires may be wound around the outer circumferential surface of the metal sheet, arranged at predetermined intervals in the extension direction.

[0022] A hollow fixed central shaft is inserted through the non-contact support roll 20a, and an air supply pipe (not shown) is connected to an opening provided at one or both ends of the fixed central shaft, and compressed air is supplied from an air supply device (not shown) such as a compressor through the air supply pipe into the inside of the non-contact support roll 20a. The supplied air is discharged from a number of holes provided on the outer circumferential surface of the non-contact support roll 20a.

[0023] Both ends of the fixed central shaft of the non-contact support roll 20a are supported by a pair of support arms 20b installed at equal intervals diagonally from the center of the support plane of the rotating base 20c. The fixed base 20e is installed and fixed to the floor surface. The fixed base 20e is connected to the rotating base 20c via the rotating shaft 20d. The output shaft of the motor 20f is connected to the end of the rotating shaft 20d on the fixed base 20e side. The motor 20f is installed and fixed within the fixed base 20e. The end of the rotating shaft 20d on the rotating base 20c side is fixed to the rotating base 20c. When the motor 20f is driven and the rotating shaft 20d rotates, the rotating base 20c rotates. The driving of the motor 20f is controlled by the control device 50.

[0024] The control device 50 is realized as a hardware configuration by elements and circuits such as a computer CPU and memory, and as a software configuration by a computer program, etc., but in Figure 1 it is depicted as a functional block realized by the cooperation of these. Those skilled in the art will naturally understand that these functional blocks can be realized in various forms by combining hardware and software. The control device 50 may be configured as a control panel, for example.

[0025] An edge sensor 30 is installed downstream of the floating roll device 20 on the conveying line. The edge sensor 30 is a sensor for detecting positional deviation in the width direction B of the workpiece W being conveyed on the conveying line. The edge sensor 30 has, for example, a light-emitting unit and a light-receiving unit. The light-emitting unit and the light-receiving unit are installed at a predetermined interval in the thickness direction C of the workpiece W so as to sandwich the workpiece W from both sides in the thickness direction C of the workpiece W. The light-emitting unit and the light-receiving unit may also be installed above and below a U-shaped housing having a gap through which the workpiece W passes.

[0026] The light-emitting unit irradiates light of a predetermined wavelength (e.g., infrared light) toward the light-receiving unit. The light-receiving unit has a light-receiving element (e.g., CCD or CMOS) arranged on a surface facing the light-emitting unit. When the light-receiving element receives the light irradiated from the light-emitting unit, it converts the received light into an electrical signal and outputs it to the control device 50 as an edge position signal. A portion of the light irradiated from the light-emitting unit is blocked by the edge of the workpiece W in the width direction B. Therefore, the edge sensor 30 can detect the edge position in the width direction of the workpiece W based on the light-receiving position of the light-receiving element. Note that an ultrasonic edge sensor may be used instead of an optical type.

[0027] FIG. 2 is a plan view schematically illustrating the conveyance device 1 shown in FIG. 1 conveying a workpiece W. As shown in FIG. 2, edge sensors 30 may be installed at both ends of the workpiece W in the width direction B. Facing the conveyance direction A of the workpiece W, a first edge sensor 30a is installed on the left end side of the width direction B, and a second edge sensor 30b is installed on the right end side. The first edge sensor 30a outputs a first edge position signal indicating the left end position of the workpiece W in the width direction B to the control device 50. The second edge sensor 30b outputs a second edge position signal indicating the right end position of the workpiece W in the width direction B to the control device 50. Note that instead of installing the edge sensors 30 at both ends of the width direction B as shown in FIG. 2, they may be installed only on either the left end or the right end. Furthermore, the edge sensor 30 may be installed upstream of the floating roll device 20 on the conveyance line. However, the purpose of the edge sensor 30 is to confirm that the workpiece W is not misaligned when it is wound by the winding device 40 located downstream. Therefore, the conveying device 1 is preferably configured so that the edge sensor 30 is disposed downstream of the floating roll device 20.

[0028] In this embodiment, the control device 50 has a meandering correction function that uses the edge sensor 30 and the motor 20f of the floating roll device 20. To realize this meandering correction function, it is necessary to provide a difference in the wrap angle of the non-contact support roll 20a around the workpiece W on the entry side and the exit side.

[0029] 3 is a side view schematically showing an example of a non-contact support roll 20a designed so that the inlet wrap angle αin is larger than the outlet wrap angle αo. The wrap angle α refers to the angle of the arc of the circumferential surface on which the workpiece W is supported in a non-contact manner by the non-contact support roll 20a. In the case of the non-contact support roll 20a, it is sufficient to specify the range of the circumferential surface on which the workpiece W comes into contact with the roll 20a, assuming that there is no gap between the non-contact support roll 20a and the workpiece W.

[0030] The wrap angle α is determined based on the positions of the unwinding device 10 and guide rolls (not shown) installed upstream of the non-contact support roll 20a, the positions of the winding device 40 and guide rolls (not shown) installed downstream, the tension applied from the upstream side, and the tension applied from the downstream side. In this specification, the wrap angle α, the angle from the highest point P1 of the workpiece W supported in a non-contact manner by the non-contact support roll 20a to the entry side, is referred to as the entry-side wrap angle αin, and the angle from the highest point P1 to the exit side, is referred to as the exit-side wrap angle αo. In the example shown in Figure 3, the wrap angle α is set to 55 degrees, the entry-side wrap angle αin is set to 45 degrees, and the exit-side wrap angle αo is set to 10 degrees.

[0031] The control device 50 detects the amount of positional deviation from a target position in the width direction B of the workpiece W based on the edge position signal input from the edge sensor 30. As shown in FIG. 2, when edge sensors 30a, 30b are installed at both ends of the width direction B of the workpiece W, the control device 50 calculates the intermediate position between the left edge position of the workpiece W indicated by the first edge position signal input from the first edge sensor 30a and the right edge position of the workpiece W indicated by the second edge position signal input from the second edge sensor 30b. The control device 50 determines the amount of positional deviation to be the difference between the calculated intermediate position and the target center position in the width direction B of the workpiece W.

[0032] When only the first edge sensor 30a is installed in the conveyance device 1, the control device 50 determines the amount of positional deviation as the difference between the target left end position of the workpiece W in the width direction B and the left end position of the workpiece W indicated by the first edge position signal input from the first edge sensor 30a. When only the second edge sensor 30b is installed in the conveyance device 1, the control device 50 determines the amount of positional deviation as the difference between the target right end position of the workpiece W in the width direction B and the right end position of the workpiece W indicated by the second edge position signal input from the second edge sensor 30b.

[0033] The control device 50 calculates the amount of rotation of the rotating shaft 20d driven by the motor 20f (i.e., the amount of rotation in the yaw direction of the non-contact support roll 20a) based on the detected amount of positional deviation (deviation) of the workpiece W in the width direction B. For example, the control device 50 calculates the amount of rotation (operation amount) of the rotating shaft 20d using PID compensation. The control device 50 feedback-controls the amount of rotation of the rotating shaft 20d so that the amount of positional deviation of the workpiece W in the width direction B becomes zero. The control device 50 supplies a control signal including the calculated amount of rotation to the motor 20f. Through this feedback control, the non-contact support roll 20a rotates in a plane parallel to the conveying direction A of the workpiece W.

[0034] 4A-4C are diagrams illustrating meandering correction control using the non-contact support roll 20a, which is designed so that the entry-side embrace angle αin is larger than the delivery-side embrace angle αo. When the entry-side embrace angle αin is larger than the delivery-side embrace angle αo, within the region of the workpiece W supported in a non-contact manner by the non-contact support roll 20a, the area facing the non-contact support roll 20a at a predetermined distance or less is larger in the region on the entry side of the highest point P1 (hereinafter referred to as the entry-side embrace region) than in the region on the delivery side (hereinafter referred to as the delivery-side embrace region). Therefore, the wind force Win received by the entry-side embrace region is larger than the wind force Wo received by the delivery-side embrace region.

[0035] FIG. 4(A) shows a state in which the amount of positional deviation from the target position in the width direction B of the workpiece W is 0, and the non-contact support roll 20a is not rotated in the yaw direction and is kept at the reference position.

[0036] 4(B) shows a state in which the workpiece W is displaced to the left in the conveying direction A from the target position in the width direction B. The control device 50 calculates the amount of counterclockwise rotation of the rotating shaft 20d according to the amount of displacement, and supplies the calculated amount of rotation to the motor 20f, causing the motor 20f to rotate the non-contact support roll 20a counterclockwise.

[0037] When the non-contact support roll 20a rotates counterclockwise, the direction of the fluid blowing onto the holding area on the inlet side changes to the right rearward direction in the conveying direction A, and the workpiece W is subjected to a moving pressure to the right. Also, the direction of the fluid blowing onto the holding area on the outlet side changes to the left frontward direction in the conveying direction A, and the workpiece W is subjected to a moving pressure to the left. Note that the backward or forward moving pressure is determined by the unwinding device 10, the winding device 40, the tension roll (not shown), the guide roll (not shown), etc., so the influence of the non-contact support roll 20a can be ignored.

[0038] When the inlet-side wrap angle αin is greater than the outlet-side wrap angle αo, the wind force Win received by the inlet-side wrap area is greater than the wind force Wo received by the outlet-side wrap area, so the pressure to move the workpiece W to the right is greater than the pressure to move it to the left. The two forces cancel each other out, and a rightward movement pressure Fr is applied to the workpiece W. This rightward movement pressure Fr increases as the counterclockwise rotation of the non-contact support roll 20a approaches 90 degrees. This rightward movement pressure Fr moves the workpiece W to the right toward the target position in the width direction B.

[0039] 4(C) shows a state in which the workpiece W is displaced to the right in the conveying direction A from the target position in the width direction B. The control device 50 calculates the amount of clockwise rotation of the rotating shaft 20d according to the amount of displacement, and supplies the calculated amount of rotation to the motor 20f, causing the motor 20f to rotate the non-contact support roll 20a clockwise.

[0040] When the non-contact support roll 20a rotates clockwise, the direction of the fluid blowing into the inlet holding area changes to the left rearward in the conveying direction A, and the workpiece W is subjected to a moving pressure to the left. Also, the direction of the fluid blowing into the outlet holding area changes to the right frontward in the conveying direction A, and the workpiece W is subjected to a moving pressure to the right.

[0041] When the inlet-side wrap angle αin is greater than the outlet-side wrap angle αo, the wind force Win received by the inlet-side wrap area is greater than the wind force Wo received by the outlet-side wrap area, so the pressure to move the workpiece W to the left is greater than the pressure to move it to the right. The two forces cancel each other out, and a leftward movement pressure Fl is applied to the workpiece W. This leftward movement pressure Fl increases as the clockwise rotation of the non-contact support roll 20a approaches -90 degrees. This leftward movement pressure Fl moves the workpiece W to the left toward the target position in the width direction B.

[0042] Fig. 5 is a side view showing an example of a non-contact support roll 20a designed so that the inlet wrap angle αin is smaller than the outlet wrap angle αo. In the example shown in Fig. 5, the wrap angle α is set to 55 degrees, the inlet wrap angle αin is set to 10 degrees, and the outlet wrap angle αo is set to 45 degrees.

[0043] 6A-6C are diagrams illustrating meandering correction control using the non-contact support roll 20a, which is designed so that the entry-side wrap angle αin is smaller than the delivery-side wrap angle αo. When the entry-side wrap angle αin is smaller than the delivery-side wrap angle αo, the area of ​​the delivery-side wrap region facing the non-contact support roll 20a at a predetermined distance or less is larger than that of the entry-side wrap region. Therefore, the wind force Wo received by the delivery-side wrap region is larger than the wind force Win received by the entry-side wrap region.

[0044] FIG. 6(A) shows a state in which the amount of positional deviation from the target position in the width direction B of the workpiece W is 0, and the non-contact support roll 20a is not rotated in the yaw direction and is kept at the reference position.

[0045] 6(B) shows a state in which the workpiece W is displaced to the left in the conveying direction A from the target position in the width direction B. The control device 50 calculates the amount of clockwise rotation of the rotating shaft 20d according to the amount of displacement, and supplies the calculated amount of rotation to the motor 20f, causing the motor 20f to rotate the non-contact support roll 20a clockwise.

[0046] When the non-contact support roll 20a rotates clockwise, the direction of the fluid blowing into the inlet holding area changes to the left rearward in the conveying direction A, and the workpiece W is subjected to a moving pressure to the left. Also, the direction of the fluid blowing into the outlet holding area changes to the right frontward in the conveying direction A, and the workpiece W is subjected to a moving pressure to the right.

[0047] When the inlet-side wrap angle αin is smaller than the outlet-side wrap angle αo, the wind force Wo received by the outlet-side wrap area is greater than the wind force Win received by the inlet-side wrap area, so the pressure to move the workpiece W to the right is greater than the pressure to move it to the left. The two forces cancel each other out, and a rightward movement pressure Fr is applied to the workpiece W. This rightward movement pressure Fr increases as the clockwise rotation of the non-contact support roll 20a approaches -90 degrees. This rightward movement pressure Fr moves the workpiece W to the right toward the target position in the width direction B.

[0048] 6(C) shows a state in which the workpiece W is displaced to the right in the conveying direction A from the target position in the width direction B. The control device 50 calculates the amount of counterclockwise rotation of the rotating shaft 20d according to the amount of displacement, and supplies the calculated amount of rotation to the motor 20f, causing the motor 20f to rotate the non-contact support roll 20a counterclockwise.

[0049] When the non-contact support roll 20a rotates counterclockwise, the direction of the fluid blowing into the holding area on the inlet side changes to the right rearward direction in the conveying direction A, and the workpiece W is subjected to a pressure to move to the right. Also, the direction of the fluid blowing into the holding area on the outlet side changes to the left frontward direction in the conveying direction A, and the workpiece W is subjected to a pressure to move to the left.

[0050] When the inlet-side wrap angle αin is smaller than the outlet-side wrap angle αo, the wind force Wo received by the outlet-side wrap area is greater than the wind force Win received by the inlet-side wrap area, so the pressure to move the workpiece W to the left is greater than the pressure to move it to the right. The two forces cancel each other out, and a leftward movement pressure Fl is applied to the workpiece W. This leftward movement pressure Fl increases as the counterclockwise rotation of the non-contact support roll 20a approaches 90 degrees. This leftward movement pressure Fl moves the workpiece W to the left toward the target position in the width direction B.

[0051] The meandering correction function according to this embodiment utilizes the difference between the wind force Win acting on the entry-side holding region and the wind force Wo acting on the exit-side holding region when the non-contact support roll 20a rotates in the yaw direction. Therefore, it cannot be used when the entry-side holding angle αin and the exit-side holding angle αo are equal, and the wind force Win acting on the entry-side holding region and the wind force Wo acting on the exit-side holding region are the same.

[0052] 7A and 7B are side views schematically showing an example of a non-contact support roll 20a designed so that the entry-side wrap angle αin and the delivery-side wrap angle αo are equal. Fig. 7B shows an example in which the workpiece W passes through the non-contact support roll 20a in a straight line without bending in the thickness direction C (wrap angle α = entry-side wrap angle αin = delivery-side wrap angle αo = 0 degrees).

[0053] 8A to 8C are diagrams illustrating meandering correction control according to a comparative example, which is an example in which the non-contact support roll 20a is rotated in the roll direction to correct the positional deviation of the workpiece W in the width direction.

[0054] FIG. 8(A) shows a state in which the amount of positional deviation from the target position in the width direction B of the workpiece W is 0, and the non-contact support roll 20a is not rotated in the roll direction and is kept at the reference position.

[0055] 8(B) shows a state in which the workpiece W is displaced to the left in the conveying direction A from the target position in the width direction B. The control device 50 rotates the non-contact support roll 20a clockwise in the roll direction in the conveying direction A according to the amount of displacement. That is, the right end of the non-contact support roll 20a is tilted toward the floor surface so that the right end of the non-contact support roll 20a approaches the floor surface.

[0056] As a result, the wind force received by the non-contact support roll 20a on the right end side of the workpiece W becomes weaker, and the wind force received by the non-contact support roll 20a on the left end side of the workpiece W becomes stronger, and a rightward moving pressure Fr is applied to the workpiece W. This rightward moving pressure Fr increases as the amount of clockwise rotation of the non-contact support roll 20a approaches -90 degrees. This rightward moving pressure Fr moves the workpiece W to the right toward the target position in the width direction B.

[0057] 8(C) shows a state in which the workpiece W is displaced to the right in the conveying direction A from the target position in the width direction B. The control device 50 rotates the non-contact support roll 20a counterclockwise in the roll direction in the conveying direction A according to the amount of displacement. That is, the left end of the non-contact support roll 20a is tilted toward the floor surface so that the left end of the non-contact support roll 20a approaches the floor surface.

[0058] As a result, the wind force received by the non-contact support roll 20a on the left end side of the workpiece W becomes weaker, and the wind force received by the non-contact support roll 20a on the right end side of the workpiece W becomes stronger, and a leftward moving pressure Fl is applied to the workpiece W. This leftward moving pressure Fl becomes larger as the counterclockwise rotation of the non-contact support roll 20a approaches 90 degrees. This leftward moving pressure Fl moves the workpiece W leftward toward the target position in the width direction B.

[0059] Comparing the method of rotating the non-contact support roll 20a in the yaw direction according to the embodiment with the method of rotating the non-contact support roll 20a in the roll direction according to the comparative example, the method according to the comparative example results in a greater load being applied to the workpiece W from the non-contact support roll 20a during correction. In the method according to the comparative example, when the right end of the non-contact support roll 20a tilts toward the floor as shown in FIG. 8(B), the portion of the right side of the workpiece W supported by the non-contact support roll 20a sinks, and a load is applied to the workpiece W such that the length of the right side of the workpiece W becomes shorter than the length of the left side. This load makes the workpiece W more likely to tear in the width direction B. In contrast, in the method according to the embodiment, the load applied to the workpiece W from the non-contact support roll 20a during correction is smaller, minimizing the risk of breakage of the workpiece W.

[0060] As described above, according to the conveying device 1 of this embodiment, the risk of breakage of the workpiece W being levitated and conveyed can be minimized by rotating the non-contact support roll 20a in the yaw direction to correct the meandering of the workpiece W. Levitation conveyance allows for low-tension conveyance without contact resistance with the roll, and is suitable for conveying thin films that are vulnerable to changes in tension during conveyance. For example, it is suitable for conveying thin-film metal foil.

[0061] In particular, lithium foil is suitable for levitation transport because it is lightweight and easily adheres to metals. Lithium foil can be used, for example, as a negative electrode material for lithium metal secondary batteries. It can also be used as a pre-dope material for the negative electrodes of lithium ion secondary batteries and lithium ion capacitors.

[0062] However, because lithium foil is lightweight, it tends to meander and is vulnerable to changes in tension. Therefore, low-load meandering correction is required, and the conveyance device 1 according to this embodiment can achieve low-load meandering correction.

[0063] The workpiece W transported by the transport device 1 according to this embodiment is not limited to lithium foil, but may include other metal foils such as copper foil, aluminum foil, stainless steel foil, titanium foil, etc. Furthermore, resin film, paper, cloth, nonwoven fabric, etc. may also be included.

[0064] The above describes the embodiments of the present disclosure in detail. The above-described embodiments merely illustrate specific examples of implementing the present disclosure. The above-described embodiments may also be configured to include machining processes such as drilling, rolling, and solvent application to a workpiece. The content of the embodiments does not limit the technical scope of the present disclosure. Many design modifications, such as changing, adding, or deleting components, are possible within the scope of the invention defined in the claims. A new embodiment incorporating design modifications will combine the effects of the combined embodiments and modifications. In the above-described embodiments, possible design modifications are emphasized by using terms such as "in this embodiment" or "in this embodiment." However, design modifications are also permitted even without such notation. Furthermore, any combination of the components included in each embodiment is also valid as an aspect of the present disclosure. Hatching on cross sections in the drawings does not limit the material of the hatched object.

[0065] In the above embodiment, the non-contact support roll 20a has been described as a type that blows air onto the workpiece W being transported to lift the workpiece W. In this regard, other types of non-contact support rolls can also be used as long as they are capable of supporting the workpiece W in a non-contact manner by utilizing a force that acts on the workpiece W in a non-contact manner. For example, an ultrasonic non-contact support roll may be used. An ultrasonic non-contact support roll has a vibrating plate (e.g., a sonotrode) installed on the transport surface facing the workpiece W, and by micro-vibrating the vibrating plate at a high frequency, a squeezed air film is formed between the workpiece W and the transport surface, and the repulsive force of the squeezed air film lifts the workpiece W.

[0066] The embodiments may be specified by the following items. [Item 1] a floating roll (20a) that supports the work (W) being conveyed in a non-contact manner by utilizing a force that acts on the work (W) in a non-contact manner, the floating roll (20a) having a cylindrical shape extending in the width direction (B) of the work (W), and at least the surface facing the work (W) being formed by a peripheral surface; a drive unit (20f) for rotating the floating roll (20a) in a yaw direction, Among the embrace angles (α) of the work (W) supported by the floating roll (20a) in a non-contact manner, an embrace angle (αin) on the inlet side from the highest point (P1) and an embrace angle (αo) on the outlet side from the highest point (P1) are set to different angles. Conveying device (1). This makes it possible to achieve meandering correction with a low risk of breakage of the workpiece (W) being levitated and transported. [Item 2] The system further includes a control unit (50) that determines the amount of rotation of the floating roll (20a) in the yaw direction based on the amount of positional deviation of the work (W) in the width direction (B) and controls the drive unit (20f) based on the determined amount of rotation. The conveying device (1) according to item 1. This enables feedback control based on the amount of positional deviation in the width direction (B) of the workpiece (W). [Item 3] When the inlet side embrace angle (αin) is set larger than the outlet side embrace angle (αo), The control unit (50) controls the workpiece (W) to move from a target position in the width direction (B) toward the conveying direction (A). left When the workpiece (W) is shifted from the target position in the width direction (B) toward the conveying direction (A), the driving unit (20f) rotates the lifting roll (20a) counterclockwise according to the amount of the shift. Right side When the lifting roll (20a) is deviated from the normal position, the drive unit (20f) rotates the lifting roll (20a) clockwise in accordance with the amount of deviation. Item 2. The conveying device (1) according to item 2. According to this, when the inlet wrap angle (αin) is set larger than the outlet wrap angle (αo), the work (W) can be guided to the target position by the angle difference and the yaw rotation of the lifting roll (20a). [Item 4] When the inlet side embrace angle (αin) is set smaller than the outlet side embrace angle (αo), The control unit (50) controls the workpiece (W) to move from a target position in the width direction (B) toward the conveying direction (A). left When the workpiece (W) is shifted from the target position in the width direction (B) toward the conveying direction (A), the driving unit (20f) rotates the lifting roll (20a) clockwise according to the amount of the shift. Right side When the lifting roll (20a) is deviated from the normal position, the drive unit (20f) rotates the lifting roll (20a) counterclockwise in accordance with the amount of deviation. Item 2. The conveying device (1) according to item 2. According to this, when the inlet wrap angle (αin) is set smaller than the outlet wrap angle (αo), the work (W) can be guided to the target position by the angle difference and the yaw rotation of the lifting roll (20a). [Item 5] The workpiece (W) is a lithium foil. 5. The conveying device (1) according to any one of items 1 to 4. This allows lightweight and easily breakable lithium foil to be transported while correcting its meandering with a low risk of breakage. [Item 6] A meandering correction method for rotating a floating roll (20a) that supports a conveyed workpiece (W) in a non-contact manner by utilizing a force that acts on the workpiece (W) in a non-contact manner, the floating roll (20a) having a cylindrical shape extending in a width direction (B) of the workpiece (W) and having at least a surface that faces the workpiece (W) formed as a peripheral surface, in a yaw direction based on a positional deviation amount of the workpiece (W) in the width direction (B), Among the embrace angles (α) of the work (W) supported by the floating roll (20a) in a non-contact manner, an embrace angle (αin) on the inlet side from the highest point (P1) and an embrace angle (αo) on the outlet side from the highest point (P1) are set to different angles. Meandering correction method. This makes it possible to achieve meandering correction with a low risk of breakage of the workpiece (W) being levitated and transported. [Industrial Applicability]

[0067] The present disclosure is applicable to the manufacture of batteries. [Explanation of symbols]

[0068] 1 conveying device, 10 unwinding device, 20 floating roll device, 20a non-contact support roll, 20b support arm, 20c rotating base, 20d rotating shaft, 20e fixed base, 20f motor, 30 edge sensor, 40 winding device, 50 control device, W work.

Claims

1. a floating roll that supports the workpiece being transported in a non-contact manner by utilizing a force that acts on the workpiece in a non-contact manner, the floating roll having a cylindrical shape that extends in the width direction of the workpiece, and at least a surface that faces the workpiece being formed by a peripheral surface; a drive unit for rotating the floating roll in a yaw direction; A control unit that determines a rotation amount in a yaw direction of the floating roll based on a positional deviation amount in the width direction of the workpiece, and controls the drive unit based on the determined rotation amount, Among the embrace angles of the work supported in a non-contact manner by the floating roll, the embrace angle from the highest point to the entry side and the embrace angle from the highest point to the exit side are set to different angles, and the embrace angle on the entry side is set to be larger than the embrace angle on the exit side, When the workpiece is deviated from the target position in the width direction to the left in the conveying direction, the control unit causes the drive unit to rotate the floating roll counterclockwise in accordance with the amount of deviation, and when the workpiece is deviated from the target position in the width direction to the right in the conveying direction, the control unit causes the drive unit to rotate the floating roll clockwise in accordance with the amount of deviation. Conveying device.

2. The workpiece is a lithium foil. The conveying device according to claim 1 .

3. A meandering correction method for rotating a floating roll in a yaw direction based on a positional deviation of the work in the width direction, the floating roll being configured as a cylindrical shape extending in the width direction of the work and having a peripheral surface that faces at least the work, the floating roll supporting the work in a non-contact manner by utilizing a force that acts on the work in a non-contact manner, Among the embrace angles of the work supported in a non-contact manner by the floating roll, the embrace angle from the highest point to the entry side and the embrace angle from the highest point to the exit side are set to different angles, and the embrace angle on the entry side is set to be larger than the embrace angle on the exit side, When the workpiece is deviated from the target position in the width direction to the left in the conveying direction, the floating roll is rotated counterclockwise in accordance with the amount of deviation, and when the workpiece is deviated from the target position in the width direction to the right in the conveying direction, the floating roll is rotated clockwise in accordance with the amount of deviation. Meandering correction method.

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