Contact rotation type turn bar and method for manufacturing web processed product

Abstract

A contact rotation type turn bar for supporting and turning a long web that is continuously transported is provided with one shaft and a plurality of omni wheels provided on the shaft so as to be independently rotatable. Each of the omni wheels is provided, on the circumferential surface thereof, with a roller that supports the web and is rotatable on an axis in a direction different from a rotation axis centered on the shaft. The turn bar urges the web so as to move to the center of the turn bar, with one or both of bending of the shaft and gradients of the diameters of the omni wheels.

Description

Contact Rotating Turn Bar and Method for Manufacturing Web Processed Product

[0001] The present invention relates to a turn bar and a method for manufacturing a web processed product, and specifically relates to a contact rotating turn bar used for conveying a web, and a method for manufacturing a web processed product using the same.

[0002] In the manufacturing of web-shaped members such as films and papers, in many cases, a raw web is formed into a long shape, conveyed along the longitudinal direction on the conveying path of a production line, and subjected to various treatments to obtain a product.

[0003] In conveying such a web, the web conveying path is not limited to a straight path, and there are cases where a curved path is required. For example, since the area for installing processing equipment is limited, it may be required to turn the conveying path to adapt to such limitation.

[0004] When turning the conveying path of a long web, in a case where the conveying path is turned in a rotation direction with the width direction of the web as the rotation axis, such a turn can be easily achieved by wrapping the web around a normal cylindrical roll such as a free roll at an appropriate wrap angle. On the other hand, when a normal cylindrical roll is used in a case where the conveying path is turned in a rotation direction with a rotation axis twisted relative to the width direction of the web, the web is guided in a direction deviating from the conveying path as the roll rotates. In this case, if an attempt is made to maintain conveyance of the web in the conveying path by applying some force to the web, slipping occurs between the web and the roll, which may cause a problem of damaging the web.

[0005] A device called a turn bar is known that enables the conveying path to be turned in a twisted direction while reducing the above-mentioned problems. Various types of turn bars are known (for example, Patent Documents 1 to 3). For example, in Patent Document 1, the roller device 10 consists of a cylindrical structure made up of a number of bearing cases 20 attached to a roller shaft 70, and a number of rollers 50 provided on the surface of this structure, which facilitates the sliding of the web on the surface of this structure and enables the conveying path to be turned in a twisted direction.

[0006] Japanese Patent Publication No. 2007-182301, Japanese Patent Publication No. 2003-160268, Japanese Utility Model Publication No. 61-056353

[0007] Turn bars, which have a generally cylindrical structure, are often installed as free rolls (i.e., rolls mounted on a shaft to rotate freely and rotated by the momentum of the web being transported). If a turn bar installed as a free roll has a large mass, a large inertial force is generated during rotation, and the peripheral speed of its surface cannot keep up with the changes in the web's transport speed, which can damage the web. Specifically, it can impose a load on the web other than the tension required for transport, resulting in undesirable phenomena such as web breakage.

[0008] If the turn bar is not a free roll but a roll that is driven and rotates at a peripheral speed suitable for the web conveying speed, the cost of installing and operating utilities for driving and controlling the roll will increase. Therefore, it is preferable for the turn bar to be a lightweight free roll.

[0009] A turn bar having a generally cylindrical structure with numerous rollers on its surface, as disclosed in Patent Document 1, etc., includes numerous components such as rollers on the surface and bearings that support them. Therefore, its mass is inevitably large, even if lightweight materials such as resin are used, and as a result it can easily damage the web.

[0010] Therefore, the object of the present invention is to provide a turn bar that can be installed and operated at low cost and that can turn the web's transport path without putting a load on the web, and a method for manufacturing web processed products using the same.

[0011] The inventors conducted studies to solve the aforementioned problems. As a result, they found that the aforementioned problems could be solved by constructing a turn bar by combining multiple omni wheels in a specific manner, and thus completed the present invention. That is, the present invention includes the following.

[0012] (1) A contact-rotating turn bar for supporting and turning a long web that is continuously transported, comprising a single shaft and a plurality of omniwheels independently rotatably mounted on the shaft, each of the omniwheels having a roller for supporting the web, the rollers being rotatably mounted on the circumferential surface of the omniwheel with respect to an axis different from the axis of rotation centered on the shaft, and the turn bar biases the web to move to the center of the turn bar by the curvature of the shaft, the gradient of the diameters of the omniwheels, or both thereof. (2) The contact-rotating turn bar according to (1), wherein the shaft has a curve and the plurality of omniwheels have equal diameters. (3) The contact-rotating turn bar according to (1), wherein the shaft has a curve and the plurality of omniwheels have a gradient in diameter, the gradient being larger at the ends of the turn bar and smaller in the center of the turn bar. (4) The contact-rotating turn bar according to (1), wherein the shaft has a curve, the plurality of omni wheels have a tapered diameter, and the tapered slope is smaller at the ends of the turn bar and larger in the center of the turn bar. (5) The contact-rotating turn bar according to (1), wherein the shaft is straight, the plurality of omni wheels have a tapered diameter, and the tapered slope is larger at the ends of the turn bar and smaller in the center of the turn bar. (6) The contact-rotating turn bar according to (1), wherein the shaft is straight, the plurality of omni wheels have a tapered diameter, and the tapered slope is smaller at the ends of the turn bar and larger in the center of the turn bar. (7) A method for manufacturing a web product, comprising the step of transporting a web, a cut piece of the web, or a web product using a turn bar according to any one of (1) to (6). (8) The method for manufacturing a web product according to (7), wherein the web is selected from the group consisting of a long film, metal foil, and paper. (9) The method for manufacturing a web product according to (7) or (8), wherein the web is transported in a reversed state.(10) The method for manufacturing a web product according to any one of (7) to (9), wherein the web cut is the widthwise end of the film cut from the film.

[0013] The present invention provides a turn bar that can be installed and operated inexpensively and that can turn the web along its transport path without putting a load on the web, and a method for manufacturing a web-processed product using the same.

[0014] Figure 1 is a schematic front view showing a first embodiment of the turn bar of the present invention and a manner of use thereof. Figure 2 is an oblique side view showing in more detail the omni wheel 110, which is a component of the turn bar 100 described in Figure 1. Figure 3 is a schematic front view showing a second embodiment of the turn bar of the present invention and a manner of use thereof. Figure 4 is a schematic front view showing a third embodiment of the turn bar of the present invention and a manner of use thereof. Figure 5 is a schematic front view showing a fourth embodiment of the turn bar of the present invention and a manner of use thereof. Figure 6 is a schematic front view showing a fifth embodiment of the turn bar of the present invention and a manner of use thereof.

[0015] The present invention will be described in detail below with reference to embodiments and examples. However, the present invention is not limited to the embodiments and examples shown below, and can be modified and implemented at will without departing from the scope of the claims and equivalents of the present invention.

[0016] In the following description, a "long web" refers to a component with a length of five times or more its width, preferably 10 times or more its width, and specifically refers to a film-like component with a length sufficient to be rolled up for storage or transport. There is no particular upper limit to the length of a long web; for example, it may be 100,000 times or less its width.

[0017] (Overview of the turn bar and the first embodiment) The turn bar of the present invention is a contact-rotating turn bar for supporting and turning a long web that is being transported continuously. That is, the turn bar of the present invention is a turn bar that contacts a long web that is being transported continuously, wraps around the web at an appropriate wrap angle, and thereby turns the transport path of the web in a rotational direction with the axial direction of the turn bar as the axis of rotation.

[0018] The turn bar of the present invention includes a single shaft and a plurality of omniwheels independently rotatably mounted on it. Figure 1 is a schematic front view showing a first embodiment of the turn bar of the present invention and a manner of use thereof. However, in Figure 1, for illustrative purposes, the omniwheel 110 is shown in a cross-sectional view. This is also the case in Figures 3 to 6. Figure 2 is an oblique side view showing in more detail the omniwheel 110, which is a component of the turn bar 100 described in Figure 1 (specifically, the elevation angle of observation is the same horizontal direction as in Figure 1, and the azimuth angle of observation is shifted by about 45° from the azimuth angle of observation in Figure 1).

[0019] In the example shown in Figure 1, the turn bar 100 comprises a single shaft 190 and a plurality of omniwheels 110 mounted on the shaft 190. Each omniwheel 110 has a suitable support mechanism (not shown), such as a bearing, and is mounted on the shaft 190 via such a support mechanism. As a result, each omniwheel 110 is independently mounted to rotate freely around the centerline 191 of the shaft 190 as its axis of rotation at the position on which each shaft 190 is mounted. On the other hand, the omniwheels 110 are mounted in a position where they do not slide in the direction of the centerline 191. In this example, there are 10 omniwheels 110 mounted on a single shaft 190, and they all have the same diameter.

[0020] An omniwheel is equipped with rollers on its circumferential surface. For example, an omniwheel may comprise a main wheel having a generally disc-shaped form and rollers provided on the circumferential surface of the main wheel. The rollers are rotatable around an axis different in direction from the axis of rotation centered on the shaft. That is, the rollers are positioned such that the direction of the center line of the shaft at the location where each omniwheel is installed is different from the direction of the axis of rotation of the rollers.

[0021] In the example shown in Figure 2, the omniwheel 110 comprises a pair of main wheels 111L and 111R having a generally disc-shaped form, and rollers 121L and 121R provided on their circumferential surfaces 111LS and 111RS.

[0022] In this example, nine rollers are provided around the entire circumference of one main wheel (i.e., 18 rollers per pair of main wheels). Each of the main wheels 111L and 111R has multiple notches and further has sub-shafts provided on the main wheel that are passed through each notch. Specifically, in the example in Figure 2, each of the main wheels 111L and 111R has nine notches 112L and 112R, and further, one sub-shaft 113L (only one of the nine is shown with a dashed line) is passed through each of the notches 112L, and one sub-shaft 113R (only one of the nine is shown with a dashed line) is passed through each of the notches 112R. The distance of all 18 sub-shafts 113R and 113L from the main wheel rotation axis is set to be the same.

[0023] Rollers 121L and 121R have a suitable support mechanism (not shown), such as bearings, and are installed so as to penetrate each sub-shaft via such support mechanism. With this structure, nine rollers are provided per main wheel, and each of rollers 121L and 121R is rotatably mounted with the centerlines 114L and 114R of the diameters of sub-shafts 113L and 113R as the axis of rotation. Rollers 121L and 121R both have the same dimensions.

[0024] Each of the rollers 121L and 121R has the shape of a so-called crown roller. A crown roller is a roller with a diameter that slopes downwards, with the ends in the direction of the roller's rotation axis being smaller and the center being larger. Due to this slope, when the crown roller is cut in a plane along its rotation axis, the shape of the cross section corresponding to the outer circumferential surface of the roller (i.e., the part of the roller's circumferential surface furthest from the rotation axis of the main wheel) can approximate the shape of the arc of the main wheel's circumferential surface. Furthermore, the diameters of the rollers 121L and 121R are such that when they are mounted on the main wheels 111L and 111R via the sub-shafts 113L and 113R, their circumferential surfaces protrude slightly from the circumferential surfaces 111LS and 111RS of the main wheels 111L and 111R.

[0025] The main wheels 111L and 111R are connected by a connecting member 115. Therefore, when the omniwheel 110 rotates, they rotate while maintaining their connected state (i.e., maintaining their relative angular relationship). The main wheels 111L and 111R have the same shape except that the positions of the holes into which the connecting member 115 fits are offset. Due to this offset, when viewed from the axis of rotation of the omniwheel 110, the position where roller 121L is provided is offset from the position where roller 121R is provided, resulting in an alternating arrangement.

[0026] The centerlines 114L and 114R of the diameters of the sub-shafts 113L and 113R are aligned with the circumferential surfaces 111LS and 111RS of the main wheels 111L and 111R, and are therefore in a different direction from the centerline 191 of the shaft 190. Specifically, in this example, the direction of the centerline of a sub-shaft, as observed from a direction perpendicular to a certain sub-shaft in the radial direction of the main wheel, is perpendicular to the direction of the centerline 191 of the shaft 190.

[0027] Due to the above characteristics, an object supported by the outer circumferential surfaces of the rollers 121L and 121R on the circumferential surfaces 111LS and 111RS of the omniwheel 110 can be easily moved in various directions relative to the shaft 190. Specifically, due to the rotation of the main wheels 111L and 111R relative to the shaft 190, the outer circumferential surfaces of the rollers 121L and 121R can be easily moved with the center line 191 of the shaft 190 as the axis of rotation. Therefore, an object supported by them can be easily moved in that direction of rotation. In addition, due to the rotation of the rollers 121L and 121R relative to the sub-shafts 113L and 113R, their outer circumferential surfaces can rotate in a direction different from the rotation direction of the main wheels 111L and 111R. Therefore, an object supported by them can also be easily moved in that direction of rotation. In addition, because the rollers 121L and 121R are arranged alternately, any object that wraps around the omniwheel 110 over a certain area or more is stably supported by the outer circumferential surfaces of the rollers 121L and 121R.

[0028] The materials constituting the shaft 190 and the omniwheel 110 are not particularly limited, and various materials known as turn bar materials, such as resin and metal, can be used. In particular, from the viewpoint of reducing weight, it is preferable to use resin for the main wheel and the rollers on its circumferential surface.

[0029] Figure 1 shows an example of a turn bar with a bend in the shaft. When the shaft has a bend, the bend may be a kink bend or a curved bow bend. Furthermore, it is preferable that there is only one bend in a single shaft, but there may be two or more bends. However, when there are multiple bends, these bends can usually be in the same direction. A preferred example of a shaft with a bend is a shaft with one kink bend in the center, as shown in Figure 1.

[0030] In cases where such a bend is present, the structure of the bent portion may be one in which the angle of the bend is fixed, or one in which the angle of the bend is adjustable. For example, a shaft with a bend may be a shaft with a fixed angle of bend obtained by bending a straight metal rod or the like, or it may be a shaft with an appropriate hinge mechanism that allows the angle of the bend to be adjusted.

[0031] In the example shown in Figure 1, the shaft 190 has a bend 192 in its center. The turn bar 100 is equipped with groups 110L and 110R of omniwheels 110 on one side and the other side of the bend 192. In this example, the web 50 is transported from the top of the turn bar 100 toward the turn bar 100 in the direction of arrow A11, turns around the turn bar 100 from the front side in the drawing, wraps around the bottom side of the turn bar 100, and is transported from the back side of the turn bar 100 toward the top in the direction of arrow A12. The turn bar 100 is installed so that the bend of the shaft 190 is convex upwards. Therefore, in this example, the turn bar 100 is installed so that the bend of the shaft 190 is concave on the side that the turn bar 100 wraps around. Furthermore, all the omniwheels 110 have the same diameter. As a result, the overall shape of the turn bar 100 on the outer circumference of the wrapped side is also concave, as shown by auxiliary line E15, with the ends protruding and the central part recessed.

[0032] Because arrows A11 and A12 are in a twisted direction, as the conveyance progresses, the newly wound web 50 tends to move in the direction of arrow A13, causing the conveyance path to shift and potentially even causing the web 50 to deviate from the turn bar. However, since the turn bar 100 is composed of numerous omniwheels 110, the effect of rollers 121L and 121R allows the conveyance path of the web 50 to easily move in the direction of arrow A14 without imposing a lot of sliding load on the web 50. Furthermore, because the shaft 190 is bent in the state described above, the web 50 is biased to move toward the center of the recess in the shaft 190, i.e., toward the bend 192 of the shaft 190. As a result, the conveyance path of the web 50 stabilizes near the bend 192.

[0033] In addition, in the state shown in Figure 1, of the 10 omniwheels 110, only the inner six support the web 50. As described above, when the transport path of the web 50 is stable near the bend 192, the inner six omniwheels 110 are biased to follow the web 50 and rotate around the shaft centerline 191 as the axis of rotation, while the outer four omniwheels 110 do not follow the web 50, are not biased, and do not rotate. The outer four omniwheels 110 only support the web 50 and rotate when the transport path of the web 50 becomes unstable for some reason and moves away from the bend 192. In this way, when a turn bar is equipped with multiple independently rotatable omniwheels, and only some of the omniwheels of the entire turn bar rotate, the inertial force of the turn bar rotation generated by following the web 50 becomes a small force that occurs only on a part of the entire turn bar. As a result, the peripheral speed of the turn bar's surface can easily follow changes in the web's transport speed, thereby reducing damage to the web.

[0034] As a result, the turn bar 100 in this example is a free-roll type that can be installed and operated at low cost, yet it can transport the web stably and turn the web along its transport path without putting stress on the web.

[0035] (Second Embodiment) Figure 3 is a schematic front view showing a second embodiment of the turn bar of the present invention and a manner of use thereof. In the example of Figure 3, the turn bar 300 comprises a single shaft 390 and a plurality of omniwheels 310 provided on the shaft 390. The structure of the omniwheels 310 is the same as that of the omniwheels 110 in the first embodiment, and each of them has a suitable support mechanism (not shown), such as a bearing, and is provided on the shaft 390 via such support mechanism. As a result, each of the omniwheels 310 is independently provided to rotate freely around the center line 391 of the diameter of the shaft 390 at the position on which each of the shafts 390 is provided. On the other hand, the omniwheels 310 are provided in a position where they do not slide in the direction of the center line 391. In this example, ten omniwheels 310 (310LA to 310LE and 310RA to 310RE) are provided on a single shaft 390.

[0036] However, in the first embodiment, all omniwheels 110 had the same diameter, but as shown in Figure 3, the omniwheel 310 has a tapered diameter. Here, the diameter is tapered so that the ends of the turn bar are tapered and the central part of the turn bar is tapered. Specifically, the diameter of the pair of omniwheels 310LA and 310RA in the center of the turn bar 300 is the smallest, the diameter of the pair of omniwheels 310LB and 310RB adjacent to them is larger than the diameter of omniwheels 310LA and 310RA, the diameter of the pair of omniwheels 310LC and 310RC adjacent to them is larger than the diameter of omniwheels 310LB and 310RB, the diameter of the pair of omniwheels 310LD and 310RD adjacent to them is larger than the diameter of omniwheels 310LC and 310RC, and the diameter of the pair of omniwheels 310LE and 310RE adjacent to them is larger than the diameter of omniwheels 310LD and 310RD.

[0037] In the example shown in Figure 3, the shaft 390 has a bend 392 in its center. In this example, the web 50 is transported from the top of the turn bar 300 toward the turn bar 300 in the direction of arrow A11, turns around the turn bar 300 by wrapping around the bottom of the turn bar 300 from the front side in the drawing, and is transported from the back side of the turn bar 300 toward the top in the direction of arrow A12. The turn bar 300 is installed so that the bend of the shaft 190 is convex downwards. Therefore, in this example, the turn bar 300 is installed so that the bend of the shaft 390 is convex on the side that the turn bar 300 wraps around. On the other hand, since the omniwheel 310 has a tapered diameter, the resulting convex shape is canceled out, and the overall shape of the turn bar 300 on the outer circumference of the wrap-around side is straight when viewed from the side, as shown by auxiliary line E35.

[0038] Similar to the example in Figure 1, since arrows A11 and A12 are in the twisting direction, as the conveyance progresses, the newly wound web 50 tends to move in the direction of arrow A33, causing the conveyance path to shift and potentially even causing the web 50 to deviate from the turn bar. However, similar to the turn bar 100 in the example in Figure 1, since the turn bar 300 is composed of a large number of omniwheels 310, the effect of the rollers provided on the circumferential surface allows the conveyance path of the web 50 to easily move in the direction of arrow A34 without placing a lot of sliding load on the web 50.

[0039] Here, because the shape of the outer circumference of the turn bar 300 on the side that is wrapped is linear as described above, the web 50 can turn with less strain compared to the example in Figure 1. Therefore, the damage to the web can be further reduced.

[0040] If the outer circumference of the side of the turn bar 300 that is wrapped is straight, this shape itself does not contribute to the biasing force that moves the web 50 toward the bend 392 of the convex part of the shaft 390. However, because there is a gradient in the diameter of the omniwheel 310, with a smaller diameter in the center and a larger diameter at the ends, the transport path of the web 50 is relatively shorter near the center of the turn bar 300 and relatively longer near the ends of the turn bar 300. Since the web 50 is subjected to longitudinal tension for transport, it is biased to move toward the center where the transport path is shorter. As a result, the transport path of the web 50 stabilizes near the bend 392.

[0041] In addition, for the same reasons explained in the example in Figure 1, the rotational inertial force of the turn bar 300 generated by following the web 50 is a small force that occurs only on a portion of the entire turn bar. As a result, the peripheral speed of the turn bar's surface can easily follow changes in the web's transport speed, reducing damage to the web.

[0042] As a result, the turn bar 300 in this example is a free-roll type that can be installed and operated at low cost, while providing stable web transport and allowing the web to be turned along its transport path without putting stress on the web.

[0043] (Third Embodiment) FIG. 4 is a front view schematically showing a third embodiment of the turn bar of the present invention and an aspect of use thereof. In the example of FIG. 4, the turn bar 400 includes a single shaft 490 and a plurality of omni wheels 410 provided on the shaft 490. The structure of the omni wheels 410 is the same as that of the omni wheels 110 in the first embodiment, each of which has a supporting mechanism such as an appropriate bearing (not shown), and is provided on the shaft 490 via the supporting mechanism. Thereby, each of the omni wheels 410 is independently provided so as to be freely rotatable around the center line 491 of the diameter of the shaft 490 as a rotation axis at a position where the respective shaft 490 is provided. On the other hand, the omni wheels 410 are provided in a positioned state without sliding in the direction of the center line 491. In this example, ten omni wheels 410 (410LA to 410LE and 410RA to 410RE) are provided on a single shaft 490.

[0044] However, in the first embodiment, all the omni wheels 110 have the same diameter, but as shown in FIG. 4, the omni wheels 410 have a gradient diameter. The diameter gradient here is a gradient opposite to that in the example of FIG. 3, in which the diameter is smaller at the ends of the turn bar and larger at the central portion of the turn bar. Specifically, the pair of omni wheels 410LA and 410RA at the central portion of the turn bar 400 has the largest diameter, the diameter of the pair of omni wheels 410LB and 410RB adjacent to the outer side thereof is smaller than the diameter of the omni wheels 410LA and 410RA, the diameter of the pair of omni wheels 410LC and 410RC adjacent to the outer side thereof is smaller than the diameter of the omni wheels 410LB and 410RB, the diameter of the pair of omni wheels 410LD and 410RD adjacent to the outer side thereof is smaller than the diameter of the omni wheels 410LC and 410RC, and the diameter of the pair of omni wheels 410LE and 410RE adjacent to the outer side thereof is smaller than the diameter of the omni wheels 410LD and 410RD.

[0045] In the example shown in Figure 4, the shaft 490 has a bend 492 in its center. In this example, the web 50 is transported from the top of the turn bar 400 toward the turn bar 400 in the direction of arrow A11, turns around the turn bar 400 from the front side in the drawing, wraps around the bottom side of the turn bar 400, and is transported from the back side of the turn bar 400 toward the top in the direction of arrow A12. The turn bar 400 is installed so that the bend of the shaft 190 is concave downwards. Therefore, in this example, the turn bar 400 is installed so that the bend of the shaft 490 is concave on the side that the turn bar 400 wraps around. On the other hand, since the omniwheel 410 has a tapered diameter, the resulting concave shape is canceled out, and the overall shape of the turn bar 400 on the outer circumference of the wrap-around side is straight when viewed from the side, as shown by auxiliary line E45.

[0046] Similar to the example in Figure 1, since arrows A11 and A12 are in the twisting direction, as the conveyance progresses, the newly wound web 50 tends to move in the direction of arrow A43, causing the conveyance path to shift and potentially even causing the web 50 to deviate from the turn bar. However, similar to the turn bar 100 in the example in Figure 1, since the turn bar 400 is composed of a large number of omniwheels 410, the effect of the rollers provided on the circumferential surface allows the conveyance path of the web 50 to easily move in the direction of arrow A44 without placing a lot of sliding load on the web 50.

[0047] Here, because the shape of the outer circumference of the turn bar 400 on the wrapped side is linear as described above, the web 50 can turn with less strain compared to the example in Figure 1. Therefore, the damage to the web can be further reduced.

[0048] If the shape on the wrapped-side outer periphery of the turn bar 400 is a linear shape as indicated by the auxiliary line E45, the shape itself does not contribute to the urging force that moves the web 50 toward the curved portion 492 of the convex part of the shaft 490. Also, unlike the example in FIG. 3, the diameter gradient of the omni-wheel does not contribute to the urging force that moves the web 50 toward the curved portion 492 of the convex part of the shaft 490. However, in the case of the turn bar 400 in FIG. 4, the relatively longer conveyance path in the central part due to the gradient where the diameter is larger at the central part can contribute to other advantages.

[0049] For example, when the conveyed web 50 is a soft film, problems such as easy slackening at the central portion in the width direction of the film may occur during conveyance. In such a case, by performing turning with the turn bar 400, such slack can be tensioned, and there is a possibility that more stable turning can be achieved.

[0050] Also, in use under specific modes such as when it is necessary to significantly reduce the conveyance tension of the web, rotational friction of the main wheel of the omni-wheel relative to the shaft may apply non-negligible large braking force to web conveyance. In such a case, a larger main wheel has relatively less rotational resistance, and as a result, the web may be conveyed relatively smoothly in the central portion. In such a case, when the turn bar 400 having the diameter gradient of the omni-wheel 410 in FIG. 4 is used, the web 50 may be urged to move toward the central portion where resistance is lower. In this case, as a result, the conveyance path of the web 50 is stabilized near the curved portion 492.

[0051] In addition, for the same reason as explained in the example of FIG. 1, the inertial force of rotation of the turn bar 400 generated by following the web 50 is a small force that is generated only in a part of the entire turn bar. As a result, the peripheral speed of the circumferential surface of the turn bar can easily follow changes in the conveyance speed of the web, and damage applied to the web can be reduced.

[0052] As a result, the turn bar 400 in this example is a free-roll type that can be installed and operated at low cost, and can provide stable web transport, while also allowing the web to be turned along its transport path without putting stress on the web.

[0053] (Fourth Embodiment) Figure 5 is a schematic front view showing a fourth embodiment of the turn bar of the present invention and a manner of use thereof. In the example of Figure 5, the turn bar 500 comprises a single shaft 590 and a plurality of omniwheels 510 provided on the shaft 590. The structure of the omniwheels 510 is the same as that of the omniwheels 110 in the first embodiment, and each of them has a suitable support mechanism (not shown) such as a bearing, and is provided on the shaft 590 via such support mechanism. As a result, each of the omniwheels 510 is independently provided to rotate freely around the center line 591 of the diameter of the shaft 590 at the position on which each of the shafts 590 is provided. On the other hand, the omniwheels 510 are provided in a position where they do not slide in the direction of the center line 591. In this example, ten omniwheels 510 (510LA to 510LE and 510RA to 510RE) are provided on a single shaft 590.

[0054] However, in the first embodiment, all omniwheels 110 had the same diameter, but as shown in Figure 5, the omniwheel 510 has a tapered diameter. Here, the diameter is tapered so that the ends of the turn bar are tapered and the central part of the turn bar is tapered. Specifically, the diameter of the pair of omniwheels 510LA and 510RA in the center of the turn bar 500 is the smallest, the diameter of the pair of omniwheels 510LB and 510RB adjacent to them is larger than the diameter of omniwheels 510LA and 510RA, the diameter of the pair of omniwheels 510LC and 510RC adjacent to them is larger than the diameter of omniwheels 510LB and 510RB, the diameter of the pair of omniwheels 510LD and 510RD adjacent to them is larger than the diameter of omniwheels 510LC and 510RC, and the diameter of the pair of omniwheels 510LE and 510RE adjacent to them is larger than the diameter of omniwheels 510LD and 510RD.

[0055] As schematically shown in Figure 5, the shaft 590 has a straight shape without any curves throughout the entire region in which it supports the web as a turn bar. In this example, the web 50 is transported from the top of the turn bar 500 toward the turn bar 500 in the direction of arrow A11, turns around by wrapping around the bottom of the turn bar 500 from the front side of the turn bar 500 in the drawing, and is transported from the back side of the turn bar 500 toward the top in the direction of arrow A12. Since the omniwheel 510 has a diameter that slopes as described above, as a result the overall shape of the turn bar 500 on the outer circumference of the wrapped side becomes a concave shape with a protruding end and a recessed center, as shown by auxiliary line E55.

[0056] Similar to the example in Figure 1, since arrows A11 and A12 are in the twisting direction, as the conveyance progresses, the newly wound web 50 tends to move in the direction of arrow A53, causing the conveyance path to shift and potentially even causing the web 50 to deviate from the turn bar. However, similar to the turn bar 100 in the example in Figure 1, since the turn bar 500 is composed of a large number of omniwheels 510, the effect of the rollers provided on the circumferential surface allows the conveyance path of the web 50 to easily move in the direction of arrow A54 without imposing a lot of sliding load on the web 50. Furthermore, there is a gradient in the diameter of the omniwheels 510, with a smaller diameter in the center and a larger diameter at the ends, so the conveyance path of the web 50 is relatively shorter near the center of the turn bar 500 and relatively longer near the ends of the turn bar 300. Since the web 50 is subjected to longitudinal tension for conveyance, it is biased to move to the center where the conveyance path is shorter. In addition, because the overall shape of the turn bar 500 on the outer circumference of the wrapped side is as described above, the web 50 is biased to move toward the center of the concave shape, i.e., toward the omni wheels 510LA and 510RA. As a result, the transport path of the web 50 stabilizes near the omni wheels 510LA and 510RA.

[0057] In addition, for the same reasons explained in the example in Figure 1, the rotational inertial force of the turn bar 300 generated by following the web 50 is a small force that occurs only on a portion of the entire turn bar. As a result, the peripheral speed of the turn bar's surface can easily follow changes in the web's transport speed, reducing damage to the web.

[0058] As a result, the turn bar 500 in this example is a free-roll type that can be installed and operated at low cost, while providing stable web transport and allowing the web to be turned along its transport path without putting stress on the web.

[0059] (Fifth Embodiment) Figure 6 is a schematic front view showing a fifth embodiment of the turn bar of the present invention and a manner of use thereof. In the example of Figure 6, the turn bar 600 comprises a single shaft 690 and a plurality of omniwheels 610 provided on the shaft 690. The structure of the omniwheels 610 is the same as that of the omniwheels 110 in the first embodiment, and each of them has a suitable support mechanism (not shown) such as a bearing, and is provided on the shaft 690 via such support mechanism. As a result, each of the omniwheels 610 is independently provided to rotate freely around the center line 691 of the diameter of the shaft 690 at the position on which each of the shafts 690 is provided. On the other hand, the omniwheels 610 are provided in a position where they do not slide in the direction of the center line 691. In this example, ten omniwheels 610 (610LA to 610LE and 610RA to 610RE) are provided on a single shaft 690.

[0060] However, in the first embodiment, all omniwheels 110 had the same diameter, but as shown in Figure 6, the omniwheel 610 has a tapered diameter. The tapered diameter here is the opposite of the example in Figure 5, with the ends of the turn bar being smaller and the center of the turn bar being larger. Specifically, the diameter of the pair of omniwheels 610LA and 610RA in the center of the turn bar 600 is the largest, the diameter of the pair of omniwheels 610LB and 610RB adjacent to them is smaller than the diameter of omniwheels 610LA and 610RA, the diameter of the pair of omniwheels 610LC and 610RC adjacent to them is smaller than the diameter of omniwheels 610LB and 610RB, the diameter of the pair of omniwheels 610LD and 610RD adjacent to them is smaller than the diameter of omniwheels 610LC and 610RC, and the diameter of the pair of omniwheels 610LE and 610RE adjacent to them is smaller than the diameter of omniwheels 610LD and 610RD.

[0061] As schematically shown in Figure 6, the shaft 690 has a straight shape without any curves throughout the entire region in which it supports the web as a turn bar. In this example, the web 50 is transported from the top of the turn bar 600 toward the turn bar 600 in the direction of arrow A11, turns around by wrapping around the bottom of the turn bar 600 from the front side of the turn bar 600 in the drawing, and is transported from the back side of the turn bar 600 toward the top in the direction of arrow A12. Since the omniwheel 610 has a diameter that slopes as described above, as a result the overall shape of the turn bar 600 on the outer circumference of the wrapped side becomes a convex shape with a protruding center and recessed ends, as shown by auxiliary line E65.

[0062] Similar to the example in Figure 1, since arrows A11 and A12 are in the twisting direction, as the conveyance progresses, the newly wound web 50 tends to move in the direction of arrow A63, causing the conveyance path to shift and potentially even causing the web 50 to deviate from the turn bar. However, similar to the turn bar 100 in the example in Figure 1, since the turn bar 600 is composed of a large number of omniwheels 610, the effect of the rollers provided on the circumferential surface allows the conveyance path of the web 50 to easily move in the direction of arrow A64 without placing a lot of sliding load on the web 50.

[0063] If the outer circumference of the wrap-around side of the turn bar 600 is convex, as shown by auxiliary line E65, then this shape itself does not contribute to the biasing force that moves the web 50 toward the omniwheels 610LA and 610RA on the convex portion of the shaft 690. Also, unlike the example in Figure 5, the gradient of the omniwheel diameter does not contribute to the biasing force that moves the web 50 toward the omniwheels 610LA and 610RA. However, in the case of the turn bar 600 in Figure 6, the relatively long transport path in the central part due to the large gradient of the central part's diameter can contribute to other advantages.

[0064] For example, if the web 50 being transported is a soft film, problems may arise during transport, such as the center of the film in the width direction becoming loose. In such cases, turning with the turn bar 600 can tighten this looseness, potentially enabling a more stable turn.

[0065] Furthermore, in certain applications, such as when it is necessary to significantly reduce the transport tension of the web, the rotational friction of the omniwheel's main wheel against the shaft may provide a significant braking force to the web transport that cannot be ignored. In such cases, a larger main wheel offers relatively less resistance to rotation, and as a result, the web may be transported relatively smoothly in the central area. In such cases, using a turn bar 600 with a gradient in diameter of the omniwheel 610 as shown in Figure 6 may bias the web 50 to move towards the central area where there is less resistance. In that case, as a result, the transport path of the web 50 stabilizes near the omniwheels 610LA and 610RA.

[0066] In addition, for the same reasons explained in the example in Figure 1, the rotational inertial force of the turn bar 600 generated by following the web 50 is a small force that occurs only on a portion of the entire turn bar. As a result, the peripheral speed of the turn bar's surface can easily follow changes in the web's transport speed, reducing damage to the web.

[0067] As a result, the turn bar 600 in this example is a free-roll type that can be installed and operated at low cost, and can provide stable web transport, while also allowing the web to be turned along its transport path without putting stress on the web.

[0068] (Modifications) The turn bar of the present invention is not limited to the examples of embodiments listed above, and various modifications may be made to the embodiments listed above. For example, in the embodiments listed above, the relationship between the shaft and sub-shaft of the omniwheel is orthogonal in direction (that is, the direction of the center line of the sub-shaft, as observed from a direction perpendicular to a certain sub-shaft in the radial direction of the main wheel, is orthogonal to the direction of the center line of the shaft), but the present invention is not limited to this, and the relationship between the shaft and sub-shaft can be various relationships other than parallel, such as an oblique relationship.

[0069] In the embodiments described above, an omniwheel is configured to have a pair of main wheels connected together, but the present invention is not limited to this, and an omniwheel may have only one main wheel, or it may have three or more main wheels.

[0070] In the embodiments described above, one main wheel had nine rollers, but the present invention is not limited to this, and the number of rollers on a single main wheel may be more or less than this.

[0071] In the embodiments described above, the shaft having a bend had only one bend and its angle was fixed. However, the present invention is not limited to this, and a single shaft may have two or more bends, and the angle of the bend may be variable.

[0072] (Applications) The turn bar of the present invention can be used in conveying various types of webs. Examples of webs include long resin films, metal foils, and paper.

[0073] One particularly preferred application of the turn bar of the present invention is the transport of so-called "edges" in film manufacturing. Generally, in the manufacture of resin films such as optical films, a process is sometimes carried out to cut and remove the widthwise edges, and these cut-off edges are called edge. The edge of the film is transported to a separate line from the widthwise central part of the film that becomes the product, i.e., the processed web, to be collected and discarded or reused. Such transport to a separate line is often in a direction away from the processing line of the film that becomes the product, and therefore, transport in a twisted direction is often required. Furthermore, in many cases, the edge of the film is of uneven thickness and has irregularities due to reasons such as being used for gripping in a stretching machine in an upstream process. In addition, since the edge itself has no value as a product, it is desirable to transport it without incurring significant costs. In transporting such edge, the turn bar of the present invention can be used particularly usefully.

[0074] Another preferred application of the turn bar of the present invention is the transport of a web for reversing its front and back sides in a web processing process for manufacturing processed web products. In the process of printing on a web, a multi-color printing device may be used in which multiple units for coating and drying paint are provided on the transport path. Due to the nature of the original application of multi-color printing, and for the design and installation of the device, these multiple units are usually provided only on one side of the web in the transport path. In such a multi-color printing device, a device called a cross inverter is provided between the units to reverse the front and back sides of the web in the transport path, thereby enabling printing on both sides. Generally, a cross inverter is a device that includes multiple turn bars. In the process of reversing the web, the turn bars in the cross inverter are often used to reverse the web non-contactively by levitating it, for example. However, in the case of non-woven fabrics or perforated webs that allow air to pass through, such a levitation-based reversal process cannot be used. Therefore, when performing double-sided printing, even with a multi-color printing device, it was not possible to perform the front-side printing process and the back-side printing process on a single transport path using a single multi-color printing device; they had to be performed separately. However, when the turn bar of the present invention is used as the turn bar constituting the cross inverter, it becomes possible to easily reverse the front and back sides between units, even when printing on a web that is permeable to air. This makes it possible to perform front and back printing with a single multi-color printing device, simplifying the process and proving to be extremely useful.

[0075] 121L, 121R Rollers 50 Webs 100, 300, 400, 500, 600 Turn bars 110, 310, 410, 510, 610 Omni wheels 110L, 110R Group of omni wheels 111L, 111R Main wheels 113L, 113R Subshafts 114L, 114R Roller centerlines 191, 391, 491, 591, 691 Shaft centerlines 115 Connecting members 190, 390, 490, 590, 690 Shafts A11, A12, A13, A14, A33, A34, A43, A44, A53, A54, A63, A64 Arrows E15, E35, E45, E55, E65 Auxiliary lines

Claims

1. A contact-rotating turn bar for supporting and turning a long web that is continuously transported, comprising: a shaft; a plurality of omniwheels independently rotatably mounted on the shaft, each omniwheel having a roller for supporting the web, the rollers being rotatably mounted on the circumferential surface of the omniwheel with respect to a rotation axis different from the axis of rotation centered on the shaft; and the turn bar biases the web to move towards the center of the turn bar by the curvature of the shaft, the gradient of the diameter of the omniwheels, or both.

2. The contact-rotating turn bar according to claim 1, wherein the shaft has a curve and the plurality of omniwheels have equal diameters.

3. The contact-rotating turn bar according to claim 1, wherein the shaft has a curve, the plurality of omniwheels have a tapered diameter, and the tapered shape is larger at the ends of the turn bar and smaller in the center of the turn bar.

4. The contact-rotating turn bar according to claim 1, wherein the shaft has a curve, the plurality of omniwheels have a tapered diameter, and the tapered shape is smaller at the ends of the turn bar and larger in the center of the turn bar.

5. The contact-rotating turn bar according to claim 1, wherein the shaft is straight, the plurality of omniwheels have a tapered diameter, and the tapered shape is larger at the ends of the turn bar and smaller in the center of the turn bar.

6. The contact-rotating turn bar according to claim 1, wherein the shaft is straight, the plurality of omniwheels have a tapered diameter, and the tapered shape is smaller at the ends of the turn bar and larger in the center of the turn bar.

7. A method for manufacturing a web product, comprising the step of transporting a web, a cut piece of the web, or a web product using a turn bar as described in any one of claims 1 to 6.

8. The method for manufacturing a web-processed product according to claim 7, wherein the web is transported after being inverted.

9. The method for manufacturing a web-processed article according to claim 7, wherein the web is selected from the group consisting of long film, metal foil, and paper.

10. The method for manufacturing a web-processed product according to claim 7, wherein the web cut is the widthwise end of the film cut from the film.

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