Bobbin unwinding device

Abstract

To suppress an increase in size of a bobbin unwinding device and also suppress variation in width of a fiber bundle unwound from the bobbin.SOLUTION: A bobbin unwinding device 15 comprises: a bobbin holder 13 that rotatably supports a bobbin 14 around which a fiber bundle F is wound; a pivot guide 61 that serves as a pivot point when the fiber bundle F unwound from the bobbin 14 is placed thereon and traversed in the lateral direction; a twist-suppressing roller 62 having an axis parallel to the lateral direction and disposed along the travel path of the fiber bundle F between the bobbin 14 and the pivot guide 61; and two guide rollers 63 (63a, 63b), each having an axis parallel to the lateral direction and disposed along the travel path of the fiber bundle F between the twist-suppressing roller 62 and the pivot guide 61.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a bobbin unwinding device that unwinds a fiber bundle from a bobbin. [Background technology]

[0002] Patent Document 1 discloses a filament winding device that winds a strip-shaped fiber bundle around the outer peripheral surface of a liner. The filament winding device is provided with a creel stand on which a plurality of bobbins on which fiber bundles are wound are arranged, and the fiber bundles unwound from each bobbin are supplied to the outer peripheral surface of the liner.

[0003] Such a filament winding device is provided with a bobbin unwinding device for unwinding a fiber bundle from a bobbin placed on a creel stand. The bobbin unwinding device has a bobbin support shaft that rotatably supports the bobbin, and a fulcrum guide (the fixed guide in Patent Document 1) on which the fiber bundle unwound from the bobbin is hung. The fiber bundle hung on the fulcrum guide is unwound from the bobbin while traversing in the axial direction of the bobbin, using the fulcrum guide as a fulcrum (see arrow T in Figure 2 of Patent Document 1).

[0004] Furthermore, a twist suppression roller (auxiliary roller of Patent Document 1) is disposed between the bobbin support shaft and the fulcrum guide, around which the fiber bundle is wound and which suppresses twisting of the wound fiber bundle as it traverses. The twist suppression roller has an axis parallel to the axial direction of the bobbin support shaft, and is configured so that the fiber bundle traverses on the circumferential surface of the twist suppression roller in the axial direction of the twist suppression roller. The fiber bundle unwound from the bobbin and heading toward the fulcrum guide is traversed while being wound around the twist suppression roller. As a result, the tension of the fiber bundle acts in a direction pressing the fiber bundle against the twist suppression roller, suppressing twisting of the fiber bundle. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-063822 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the configuration of the bobbin unwinding device as disclosed in Patent Document 1 has a problem in that the width of the fiber bundle unwound from the bobbin varies. The inventors of the present application have thoroughly investigated the reason for this problem and have concluded that it is caused by an increase in the angle (hereinafter referred to as the unwinding angle) between the running direction of the fiber bundle from near the end of the bobbin toward the fulcrum guide and the circumferential direction (rotation direction) of the twist suppression roller when viewed from a direction perpendicular to the axial direction of the twist suppression roller. This will be explained in detail below.

[0007] The fiber bundle wound around the twist suppression roller is subjected to a frictional force along the circumferential direction of the twist suppression roller. This frictional force is divided into a force acting in the running direction of the fiber bundle and a force acting in the width direction of the fiber bundle. Here, the larger the above-mentioned pull-out angle, the greater the force acting in the width direction of the fiber bundle out of the frictional force applied to the fiber bundle. As a result, the fiber bundle fluctuates in the width direction.

[0008] For example, the unwinding angle can be reduced by locating the fulcrum guide far away from the bobbin and lengthening the path of the fiber bundle unwound from the bobbin to the fulcrum guide. However, this would result in another problem: the bobbin unwinding device would become larger.

[0009] An object of the present invention is to suppress fluctuations in the width of a fiber bundle unwound from a bobbin while suppressing an increase in the size of the bobbin unwinding device. [Means for solving the problem]

[0010] The bobbin unwinding device of the present invention includes a bobbin support shaft that rotatably supports a bobbin around which a fiber bundle is wound; a fulcrum guide around which the fiber bundle unwound from the bobbin is hung and which serves as a fulcrum when the fiber bundle is traversed in the axial direction of the bobbin support shaft; a torsion suppression roller having an axis parallel to the axial direction and arranged midway along a travel path for the fiber bundle formed between the bobbin and the fulcrum guide; and at least one guide roller having an axis parallel to the axial direction and arranged midway along the travel path for the fiber bundle formed between the torsion suppression roller and the fulcrum guide, wherein the guide roller is configured so that the fiber bundle traverses on the circumferential surface of the guide roller in the axial direction and is arranged at a position deviated from the shortest path connecting the torsion suppression roller and the fulcrum guide when viewed in the axial direction.

[0011] In the present invention, a guide roller is disposed midway along the travel path of the fiber bundle between the twist suppression roller and the fulcrum guide, and this guide roller is configured so that the fiber bundle traverses in the axial direction on its peripheral surface. In other words, when the fiber bundle is unwound, the fulcrum for the traverse of the fiber bundle remains the fulcrum guide, not the guide roller. Furthermore, the guide roller is disposed at a position that is off the shortest path connecting the twist suppression roller and the fulcrum guide when viewed from the axial direction. Therefore, the path length of the fiber bundle from the bobbin to the fulcrum guide can be lengthened without increasing the linear distance between the bobbin and the fulcrum guide, and as a result, the unwinding angle can be reduced. Therefore, it is possible to suppress fluctuations in the width of the fiber bundle unwound from the bobbin while suppressing an increase in the size of the bobbin unwinding device.

[0012] In the bobbin unwinding device of the present invention, the length of the twist suppression roller in the axial direction is preferably 1 to 1.5 times the length of the region of the bobbin around which the fiber bundle is wound in the axial direction.

[0013] If the axial length of the twist suppression roller is too short, the fiber bundle may fall off the end of the twist suppression roller during traversal, while if the axial length is too long, the bobbin unwinding device becomes large. According to the present invention, it is possible to prevent the fiber bundle from falling off the twist suppression roller during traversal while suppressing an increase in the size of the bobbin unwinding device.

[0014] In the bobbin unwinding device of the present invention, the fulcrum guide is preferably a roller member having an axis perpendicular to the axial direction.

[0015] According to the present invention, by hanging the fiber bundle on the fulcrum guide, which is a roller member, the fiber bundle unwound from the bobbin can be twisted by 90 degrees and guided downstream of the fulcrum guide.

[0016] In the bobbin unwinding device of the present invention, it is preferable that the maximum path length of the fiber bundle traveling between the fulcrum guide and the downstream-most guide roller, which is the guide roller arranged immediately upstream of the fulcrum guide in the traveling direction of the fiber bundle, is 20 to 100 times the width of the fiber bundle.

[0017] In the present invention, the fiber bundle is twisted 90 degrees on its way from the most downstream guide roller to the fulcrum guide. In this configuration, the travel path of a portion of the fiber bundle in the width direction (hereinafter, the widthwise portion) from the most downstream guide roller to the fulcrum guide is approximately linear so as to take the shortest path. On the other hand, the travel path of the other portion of the fiber bundle in the width direction (hereinafter, the widthwise other portion) cannot take the shortest path and is longer than the travel path of the widthwise portion. In this situation, the widthwise other portion is pulled toward the widthwise portion in an attempt to travel the shortest path, resulting in a narrower width of the fiber bundle. Here, increasing the distance between the most downstream guide roller and the fulcrum guide reduces the variation in the path length between the widthwise portion and the widthwise other portion, thereby preventing the fiber bundle from becoming narrower. On the other hand, if the distance between the most downstream guide roller and the fulcrum guide is too far, the bobbin unwinding device becomes larger. According to the present invention, it is possible to prevent the width of the fiber bundle from becoming narrower while preventing the bobbin unwinding device from becoming larger. The maximum path length of the fiber bundle in the present invention means the maximum length of the path length of the fiber bundle that varies due to traversal.

[0018] In the bobbin unwinding device of the present invention, it is preferable that the winding angle at which the fiber bundle is wound around each of the guide rollers is 45 degrees or more and 240 degrees or less when viewed from the axial direction for all the guide rollers.

[0019] According to the present invention, by setting the winding angle to 45 degrees or more, the fiber bundle can be tightly wound around the guide roller. This makes it possible to suppress axial twisting of the fiber bundle when the fiber bundle traverses the circumferential surface of the guide roller in the axial direction. In addition, by setting the winding angle to 240 degrees or less, the fiber bundle wound around the guide roller is less likely to cross the upstream and downstream portions of the guide roller when viewed in the axial direction. This makes it possible to suppress interference and entanglement between the portion of the fiber bundle traveling upstream and the portion of the fiber bundle traveling downstream of the guide roller.

[0020] In the bobbin unwinding device of the present invention, it is preferable that the winding angle at which the fiber bundle is wound around each of the guide rollers is 70 degrees or more and 200 degrees or less when viewed from the axial direction for all the guide rollers.

[0021] According to the present invention, by setting the winding angle to 70 degrees or more, the fiber bundle can be wound more firmly around the guide roller. This further suppresses axial twisting of the fiber bundle when it traverses the circumferential surface of the guide roller in the axial direction. In addition, by setting the winding angle to 200 degrees or less, it is possible to prevent the fiber bundle wound around the guide roller from crossing the upstream and downstream portions of the guide roller when viewed in the axial direction. This prevents the portion of the fiber bundle traveling upstream of the guide roller and the portion of the fiber bundle traveling downstream from interfering with each other and becoming entangled.

[0022] In the bobbin unwinding device of the present invention, it is preferable that the winding angle at which the fiber bundle is wound around the twist suppression roller is 70 degrees or more and 200 degrees or less when viewed from the axial direction.

[0023] According to the present invention, by setting the winding angle to 70 degrees or more, the fiber bundle can be tightly wound around the twist suppression roller. This makes it possible to suppress axial twisting of the fiber bundle when the fiber bundle traverses the circumferential surface of the twist suppression roller in the axial direction. In addition, by setting the winding angle to 200 degrees or less, it is possible to prevent the fiber bundle wound around the twist suppression roller from crossing the upstream and downstream portions of the twist suppression roller when viewed in the axial direction. This makes it possible to prevent the portion of the fiber bundle traveling upstream of the twist suppression roller and the portion of the fiber bundle traveling downstream from interfering with each other and becoming entangled. [Brief explanation of the drawings]

[0024] [Figure 1] 1 is a perspective view showing a filament winding device according to an embodiment of the present invention. [Figure 2]FIG. 2 is a block diagram showing the electrical configuration of the filament winding device. [Figure 3] 1(a) and 1(b) are front views of the helical winding unit. [Figure 4] FIG. 1 is a perspective view showing a configuration of a bobbin unwinding device according to an embodiment of the present invention. [Figure 5] 1 is a diagram showing the bobbin unwinding device according to the present embodiment as viewed from the left and right direction. FIG. [Figure 6] 1 is a diagram showing a bobbin unwinding device according to an embodiment of the present invention as viewed from above and below. [Figure 7] FIG. 10 is a diagram of a bobbin unwinding device according to a first modified example, viewed from the left and right direction. [Figure 8] FIG. 10 is a diagram showing a bobbin unwinding device according to a first modified example as viewed from above and below. [Figure 9] FIG. 10 is a diagram of a bobbin unwinding device according to a second modified example, viewed from the left and right direction. [Figure 10] FIG. 10 is a diagram of a bobbin unwinding device according to a third modified example, viewed from the left and right direction. [Figure 11] FIG. 10 is a view of a bobbin unwinding device according to a fourth modified example, as viewed from the front-rear direction. [Figure 12] FIG. 11 is a view of a bobbin unwinding device according to a fifth modified example, as viewed from the front-rear direction. DETAILED DESCRIPTION OF THE INVENTION

[0025] (filament winding device) An embodiment of the present invention will be described. FIG. 1 is a perspective view showing a filament winding device 1 according to this embodiment. FIG. 2 is a block diagram showing the electrical configuration of the filament winding device 1. For convenience of explanation, the directions shown in FIG. 1 (front-rear direction and left-right direction) are defined. The front-rear direction and left-right direction are directions parallel to the horizontal direction. The front-rear direction and left-right direction are perpendicular to each other. Furthermore, the direction perpendicular to both the front-rear direction and left-right direction is defined as the up-down direction. The up-down direction is the vertical direction in which gravity acts.

[0026] The filament winding apparatus 1 is a multi-fiber winding apparatus that simultaneously winds multiple fiber bundles F (see FIG. 3) around a liner L. The filament winding apparatus 1 includes a winding device 2, multiple creel stands 3, and multiple pre-processing sections 4. The filament winding apparatus 1 is configured generally symmetrically overall. The winding device 2 is a device for winding the fiber bundle F around a cylindrical liner L. The fiber bundle F is, for example, a fiber material such as carbon fiber impregnated with a thermosetting or thermoplastic synthetic resin. The fiber bundle F has a flat ribbon shape. The shape of the liner L can vary depending on the final product. For example, if the final product is a pressure tank, a liner L having dome sections on both sides of the cylindrical section is used, as shown in FIG. 1. The liner L can be made of high-strength aluminum, metal, resin, or the like. After the fiber bundle F is wound around the liner L, a thermal curing process such as baking or a cooling process can be performed to obtain a final product such as a high-strength pressure tank.

[0027] Hereinafter, the longitudinal direction of the fiber bundle F will be simply referred to as the longitudinal direction. The direction perpendicular to the longitudinal direction and defining the width of the fiber bundle F will be referred to as the width direction of the fiber bundle F, or simply as the width direction. For ease of explanation, the direction in which the center of the fiber bundle F runs in the width direction will be referred to as the running direction of the fiber bundle F, or simply as the running direction. In real space, the specific direction of the width direction can change depending on the position of the fiber bundle F in the running direction. The width direction changes when the running fiber bundle F is twisted by some means.

[0028] The multiple creel stands 3 are arranged, for example, on both sides of the winding device 2 in the left-right direction. The multiple creel stands 3 are arranged, for example, near the rear end of the winding device 2 in the front-rear direction. Each creel stand 3 has, for example, a substantially rectangular parallelepiped frame 11 extending in the front-rear direction. The frame 11 is provided with, for example, one or more bobbin holder groups 12. The bobbin holder groups 12 are provided, for example, corresponding to each of the multiple nozzle units 53 of the helical winding unit 50 described below. Each bobbin holder group 12 has, for example, a multiple (five in this embodiment) bobbin holders 13 (bobbin support shafts of the present invention) lined up in the front-rear direction. Each bobbin holder 13 has, for example, a shaft extending in the left-right direction. Each bobbin holder 13 rotatably supports a bobbin 14 around which a fiber bundle is wound. In this embodiment, one creel stand 3 is provided with, for example, nine bobbin holder groups 12, each of which has five bobbins 14 attached thereto (i.e., a total of 45 bobbins 14 arranged). Five fiber bundles are supplied collectively from the five bobbins 14 belonging to each bobbin holder group 12. The multiple fiber bundles supplied from the creel stand 3 are wound around a liner L by a helical winding unit 50. Note that, although two creel stands 3 are illustrated in FIG. 1, the number of creel stands 3 is not limited to this. Also, to avoid complication of the drawing, only one of the multiple bobbin holder groups 12 is illustrated in FIG. 1.

[0029] The creel stand 3 is provided with a bobbin unwinding device 15 shown in Fig. 4. The bobbin unwinding device 15 is a device for unwinding a fiber bundle F from each bobbin 14. Hereinafter, for convenience of explanation, the fiber bundle F immediately after being unwound from each bobbin 14 will also be referred to as a unit fiber bundle Fu (see, for example, Fig. 4). The detailed configuration of the bobbin unwinding device 15 will be described later.

[0030] The plurality of pre-treatment sections 4 are configured to perform predetermined pre-treatments on the plurality of unit fiber bundles Fu and the fiber bundles FI described below. The plurality of pre-treatment sections 4 are arranged, for example, between the corresponding creel stands 3 and helical winding units 50 (described below) in the running direction of the fiber bundles.

[0031] Each pre-treatment section 4 has a fiber bundle joining device (not shown) and a fiber bundle feeding device (not shown). The fiber bundle joining device is configured to join a plurality of unit fiber bundles Fu (for example, five unit fiber bundles Fu) in the width direction to form a single wide fiber bundle F (hereinafter referred to as fiber bundle FI; see FIG. 3). The fiber bundle feeding device is configured to send the fiber bundle FI downstream in the traveling direction while twisting it, for example, by approximately 90 degrees.

[0032] (Wrapping device) A more specific configuration of the winding device 2 will be described. As shown in Fig. 1, the winding device 2 includes a base 20, a support unit 30 (a first support unit 31 and a second support unit 32), a hoop winding unit 40, and a helical winding unit 50.

[0033] The base 20 supports the support unit 30, the hoop winding unit 40, and the helical winding unit 50. A plurality of rails 21 extending in the front-rear direction are installed on the upper surface of the base 20. The support unit 30 and the hoop winding unit 40 are movable in the front-rear direction along the rails 21. On the other hand, the helical winding unit 50 is, for example, fixed in position relative to the base 20. As shown in FIG. 1 , the first support unit 31, the hoop winding unit 40, the helical winding unit 50, and the second support unit 32 are arranged in this order from front to rear.

[0034] The support unit 30 has a first support unit 31 and a second support unit 32. As shown in FIG. 1, the first support unit 31 is disposed forward of the hoop winding unit 40. The second support unit 32 is disposed rearward of the helical winding unit 50. The support unit 30 supports the liner L rotatably about an axis via a support shaft 33 extending in the axial direction (front-rear direction) of the liner L. The support unit 30 has a movement motor 34 and a rotation motor 35 (see FIG. 2). The movement motor 34 moves the support unit 30 (the first support unit 31 and the second support unit 32) in the front-rear direction along the rail 21. The rotation motor 35 rotates the support shaft 33 to rotate the liner L about its axis. The operation of the movement motor 34 and the rotation motor 35 is controlled by a control device 5.

[0035] The hoop winding unit 40 performs hoop winding on the circumferential surface of the liner L. Hoop winding is a winding method in which a fiber bundle is wound in a direction approximately perpendicular to the axial direction of the liner L. As shown in FIG. 1 , the hoop winding unit 40 has, for example, a main body 41, a rotating member 42, and multiple (five in this embodiment) bobbin holders 43. The main body 41 is movable in the front-rear direction along the rail 21. The rotating member 42 is an annular member having a passage hole 44 formed therein through which the liner L can pass. The rotating member 42 is supported by the main body 41 in a state in which it can rotate around the axis of the liner L. The multiple bobbin holders 43 are attached to the rotating member 42 at equal intervals in the circumferential direction. Each bobbin holder 43 has a rotation shaft extending in the front-rear direction and rotatably supports a bobbin (not shown) around which a fiber bundle is wound.

[0036] The hoop winding unit 40 has a movement motor 46 and a rotation motor 47 (see FIG. 2). The movement motor 46 moves the main body 41 back and forth along the rail 21. The rotation motor 47 rotates the rotation member 42 around the axis of the liner L. The operations of the movement motor 46 and the rotation motor 47 are controlled by the control device 5. When performing hoop winding, the control device 5 rotates the rotation member 42 while moving the main body 41 back and forth along the rail 21. As a result, fiber bundles are pulled out from each bobbin rotating around the liner L, and multiple fiber bundles are simultaneously hoop-wound around the circumferential surface of the liner L.

[0037] The helical winding unit 50 performs helical winding on the circumferential surface of the liner L. Helical winding is a winding method in which a plurality of fiber bundles F (more specifically, a plurality of fiber bundles FI) are wound in a direction generally parallel to the axial direction of the liner L. The helical winding unit 50 has, for example, a main body 51, a frame member 52, and a plurality of (nine in this embodiment) nozzle units 53. The main body 51 is fixed to, for example, the base 20. The frame member 52 is an annular member having a passage hole 54 formed therein, through which the liner L can pass. The frame member 52 is supported by the main body 51. The plurality of nozzle units 53 are arranged radially around the axis of the liner L. Each nozzle unit 53 is attached to the frame member 52.

[0038] 3(a) and 3(b) are front views of the helical winding unit 50. In detail, FIG. 3(a) illustrates a state in which the fiber bundle FI is being wound around the cylindrical portion of the liner L. FIG. 3(b) illustrates a state in which the fiber bundle FI is being wound around the dome portion of the liner L. The nozzle unit 53 has a guide body 55 that guides the fiber bundle FI into the liner L. The guide body 55 extends in the radial direction of the liner L (hereinafter simply referred to as the radial direction) and is configured to be movable in the radial direction and rotatable around a rotation axis extending in the radial direction. Guide rollers 56 are arranged on the radial outside of each nozzle unit 53. Five fiber bundles FI unwound from each bobbin holder group 12 of the creel stand 3 are introduced into one of the guide bodies 55 via the guide roller 56 and supplied to the liner L from the tip of the guide body 55.

[0039] The helical winding unit 50 has a guide movement motor 57 and a guide rotation motor 58 (see FIG. 2). The guide movement motor 57 moves each of the guide bodies 55 in the radial direction all at once. The guide rotation motor 58 rotates each of the guide bodies 55 in the radial direction all at once. The operation of the guide movement motor 57 and the guide rotation motor 58 is controlled by the control device 5. When performing helical winding, the control device 5 passes the liner L through the passage hole 54 while slowly rotating it around the axis. At the same time, the control device 5 rotates the guide bodies 55 of each nozzle unit 53 appropriately around the rotation axis while moving them appropriately in the radial direction. As a result, the fiber bundle FI is appropriately pulled out from the tip of the guide body 55 of each nozzle unit 53, and a total of nine fiber bundles FI are simultaneously helically wound around the circumferential surface of the liner L.

[0040] (Bobbin unwinding device) Next, a more specific configuration of the bobbin unwinding device 15 will be described below with reference to Figs. 4 to 6. Fig. 4 is a perspective view showing the configuration of the bobbin unwinding device 15 according to this embodiment. Fig. 5 is a view of the bobbin unwinding device 15 as viewed from the left and right. Fig. 6 is a view of the bobbin unwinding device 15 as viewed from the top and bottom. As shown in Fig. 4, the bobbin unwinding device 15 includes a bobbin holder 13, a fulcrum guide 61, a torsion suppression roller 62, and two guide rollers 63.

[0041] The fulcrum guide 61 is a member on which the fiber bundle F (unit fiber bundle Fu) unwound from the bobbin 14 supported by the bobbin holder 13 is hung. The fiber bundle F unwound from the bobbin 14 and hung on the fulcrum guide 61 is unwound from the bobbin 14 while traversing from the left end to the right end of the bobbin 14 along the axial direction of the bobbin 14 (i.e., the left-right direction) with the fulcrum guide 61 as a fulcrum. More strictly speaking, the fiber bundle F is unwound from the bobbin 14 while traversing from the left end to the right end of the region W of the bobbin 14 around which the fiber bundle F is wound (see FIG. 6). Therefore, the fulcrum guide 61 is a guide that serves as a fulcrum when the fiber bundle F is traversed in the left-right direction.

[0042] As shown in FIG. 4, the fulcrum guide 61 is a roller member having an axis parallel to the vertical direction. In other words, the fulcrum guide 61 is a rotatable cylindrical member having an axis perpendicular to the axial direction (i.e., the left-right direction) of the bobbin holder 13. Note that "parallel to the vertical direction" includes not only the case where it is parallel to the vertical direction but also the case where it is approximately parallel to the vertical direction. Similarly, "perpendicular to the axial direction of the bobbin holder 13" includes not only the case where it is perpendicular to the axial direction of the bobbin holder 13 but also the case where it is approximately perpendicular to the axial direction of the bobbin holder 13. As shown in FIGS. 5 and 6, the fiber bundle F unwound from the bobbin 14 is wound around the circumferential surface of the fulcrum guide 61, thereby twisting the width direction of the fiber bundle F by 90 degrees. The fulcrum guide 61 is disposed, for example, behind and below the bobbin holder 13 (see FIGS. 4 and 5). The fulcrum guide 61 is disposed below the bobbin holder 13 near the center in the left-right direction (see FIG. 6). However, the position where the fulcrum guide 61 is arranged is not limited to this. The width direction of the fiber bundle F hung on the fulcrum guide 61 is approximately parallel to the axis of the fulcrum guide 61 (see FIG. 5).

[0043] The twist suppression roller 62 is a roller around which the fiber bundle F unwound from the bobbin 14 is wound, and is a roller for suppressing twisting of the wound fiber bundle F as it traverses. As shown in FIG. 4, the twist suppression roller 62 has an axis parallel to the left-right direction. Note that "parallel to the left-right direction" includes not only the case where it is parallel to the left-right direction but also the case where it is approximately parallel to the left-right direction. As shown in FIG. 6, the length of the twist suppression roller 62 in the left-right direction is preferably 1 to 1.5 times the length of the region W of the bobbin 14 around which the fiber bundle F is wound in the left-right direction. In this embodiment, for example, the length of the twist suppression roller 62 in the left-right direction is slightly longer than the length of the region W of the bobbin 14 around which the fiber bundle F is wound in the left-right direction. In other words, the length of the twist suppression roller 62 in the left-right direction is 1 to 1.5 times the length of the region W of the bobbin 14 in the left-right direction.

[0044] 5, the twist suppression roller 62 is disposed in the middle of the travel path of the fiber bundle F formed between the bobbin 14 and the fulcrum guide 61. The twist suppression roller 62 is disposed, for example, in front of the bobbin holder 13 and below the axis of the bobbin holder 13 (see FIGS. 4 and 5). However, the position where the twist suppression roller 62 is disposed is not limited thereto.

[0045] As shown in Fig. 5, when viewed from the left-right direction, the winding angle α at which the fiber bundle F is wound around the twist suppression roller 62 is preferably 70 degrees or more and 200 degrees or less. The winding angle α is the angle α formed by a line segment connecting a contact start position P1, where the fiber bundle F starts to contact the twist suppression roller 62, to the axis Q1 of the twist suppression roller 62, and a line segment connecting a release position P2, where the fiber bundle F separates from the twist suppression roller 62, to the axis Q1, when viewed from the left-right direction (see Fig. 5). In this embodiment, the winding angle α is, for example, approximately 150 degrees. However, the winding angle α may vary slightly depending on the amount of the fiber bundle F.

[0046] The two guide rollers 63 are rollers around which the fiber bundle F is wound on its way from the twist suppression roller 62 to the fulcrum guide 61. As shown in Fig. 4, each of the two guide rollers 63 has an axis parallel to the left-right direction. Note that "parallel to the left-right direction" includes not only the case where it is parallel to the left-right direction, but also the case where it is approximately parallel to the left-right direction. The length of each guide roller 63 in the left-right direction is approximately the same as the length of the twist suppression roller 62 in the left-right direction.

[0047] As shown in Figures 4 and 5, two guide rollers 63 are arranged in the middle of the running path of the fiber bundle F formed between the twist suppression roller 62 and the fulcrum guide 61. The two guide rollers 63 are composed of an upstream guide roller 63a arranged on the upstream side in the running direction of the fiber bundle F and a downstream guide roller 63b arranged on the downstream side. In the running direction of the fiber bundle F, the downstream guide roller 63b is a guide roller arranged immediately upstream of the fulcrum guide 61. In other words, the downstream guide roller 63b corresponds to the most downstream guide roller of the present invention. Note that "in the running direction of the fiber bundle F, the downstream guide roller 63b is arranged immediately upstream of the fulcrum guide 61" means that no other guide rollers 63 are arranged between the downstream guide roller 63b and the fulcrum guide 61 in the running direction of the fiber bundle F.

[0048] The upstream guide roller 63a is disposed, for example, behind and below the bobbin holder 13 and behind and above the fulcrum guide 61 (see FIGS. 4 and 5). Furthermore, the upstream guide roller 63a is disposed below the torsion suppression roller 62. However, the position at which the upstream guide roller 63a is disposed is not limited thereto. The downstream guide roller 63b is disposed, for example, in front of and below the bobbin holder 13 and in front of the fulcrum guide 61 (see FIGS. 4 and 5). Furthermore, the downstream guide roller 63b is disposed in front of and below the upstream guide roller 63a and the torsion suppression roller 62 (see FIGS. 4 and 5). Furthermore, the axis Q3 of the downstream guide roller 63b is disposed above the fulcrum guide 61 (see FIGS. 4 and 5). However, the position at which the downstream guide roller 63b is disposed is not limited thereto.

[0049] The upstream guide roller 63a is configured so that the fiber bundle F traverses in the left-right direction on the circumferential surface of the upstream guide roller 63a. Similarly, the downstream guide roller 63b is configured so that the fiber bundle F traverses in the left-right direction on the circumferential surface of the downstream guide roller 63b. The two guide rollers 63a, 63b are arranged at positions off the shortest path connecting the torsion suppression roller 62 and the fulcrum guide 61 when viewed from the left-right direction.

[0050] As shown in Fig. 5, when viewed from the left-right direction for the two guide rollers 63, the winding angle at which the fiber bundle F is wound around the guide rollers 63 is preferably 20 degrees or more and 280 degrees or less, more preferably 45 degrees or more and 240 degrees or less, and most preferably 70 degrees or more and 200 degrees or less. More specifically, when viewed from the left-right direction, the winding angle β at which the fiber bundle F is wound around the upstream guide roller 63a is preferably 20 degrees or more and 280 degrees or less, more preferably 45 degrees or more and 240 degrees or less, and most preferably 70 degrees or more and 200 degrees or less. The winding angle β is the angle β formed by the line segment connecting the contact start position P3 where the fiber bundle F starts to contact the upstream guide roller 63a and the axis Q2 of the upstream guide roller 63a, and the line segment connecting the release position P4 where the fiber bundle F separates from the upstream guide roller 63a and the axis Q2, when viewed from the left-right direction (see Fig. 5). Furthermore, when viewed from the left-right direction, the winding angle γ at which the fiber bundle F is wound around the downstream guide roller 63b is preferably 20 degrees or more and 280 degrees or less, more preferably 45 degrees or more and 240 degrees or less, and most preferably 70 degrees or more and 200 degrees or less. The winding angle γ is the angle γ formed by the line segment connecting the contact start position P5 where the fiber bundle F starts to contact the downstream guide roller 63b and the axis Q3 of the downstream guide roller 63b, and the line segment connecting the release position P6 where the fiber bundle F separates from the downstream guide roller 63b and the axis Q3 when viewed from the left-right direction (see FIG. 5). In this embodiment, the winding angle β is, for example, approximately 180 degrees, and the winding angle γ is, for example, approximately 180 degrees.

[0051] The maximum path length X (see FIG. 5) of the fiber bundle F traveling between the downstream guide roller 63b and the fulcrum guide 61 is preferably 20 to 100 times the width of the fiber bundle F. Here, the path length of the fiber bundle F traveling between the downstream guide roller 63b and the fulcrum guide 61 varies as the fiber bundle F traverses. The maximum path length X refers to the path length when the path length of the fiber bundle F traveling between the downstream guide roller 63b and the fulcrum guide 61 is at its maximum.

[0052] (effect) The bobbin unwinding device 15 of this embodiment includes a bobbin holder 13 that rotatably supports a bobbin 14 around which a fiber bundle F is wound, a fulcrum guide 61 around which the fiber bundle F unwound from the bobbin 14 is hung and which serves as a fulcrum when the fiber bundle F traverses in the left-right direction, a twist suppression roller 62 having an axis parallel to the left-right direction and disposed midway along the travel path of the fiber bundle F formed between the bobbin 14 and the fulcrum guide 61, and two guide rollers 63 (63a, 63b) having axes parallel to the left-right direction and disposed midway along the travel path of the fiber bundle F formed between the twist suppression roller 62 and the fulcrum guide 61. The two guide rollers 63 are configured so that the fiber bundle F traverses in the left-right direction on the circumferential surfaces of the guide rollers 63, and are disposed at positions off the shortest path connecting the twist suppression roller 62 and the fulcrum guide 61 when viewed from the left-right direction.

[0053] In this embodiment, a guide roller 63 is disposed midway along the travel path of the fiber bundle F between the twist suppression roller 62 and the fulcrum guide 61, and this guide roller 63 is configured so that the fiber bundle F traverses in the axial direction on its circumferential surface. In other words, when the fiber bundle F is unwound, the fulcrum for the traverse of the fiber bundle F remains the fulcrum guide 61, not the guide roller 63. Furthermore, the guide roller 63 is disposed at a position that is off the shortest path connecting the twist suppression roller 62 and the fulcrum guide 61 when viewed from the axial direction. This makes it possible to lengthen the path length of the fiber bundle from the bobbin 14 to the fulcrum guide 61 without lengthening the linear distance between the bobbin 14 and the fulcrum guide 61. As a result, it is possible to reduce the pull-out angle θ (see FIG. 6 ) formed between the travel direction of the fiber bundle F from near the end of the bobbin 14 toward the fulcrum guide 61 and the circumferential direction R of the twist suppression roller 62 (i.e., the rotation direction; see the dashed-dotted arrow in FIG. 6 ). When the unwinding angle θ decreases, the component of the friction force that the fiber bundle F wound around the twist suppression roller 62 receives from the twist suppression roller 62 acting in the running direction of the fiber bundle F increases, while the component acting in the width direction of the fiber bundle F decreases. As a result, fluctuations in the width of the fiber bundle F are suppressed. Therefore, it is possible to suppress fluctuations in the width of the fiber bundle unwound from the bobbin while suppressing an increase in the size of the bobbin unwinding device.

[0054] Furthermore, in the bobbin unwinding device 15 of this embodiment, the length in the left-right direction of the twist suppression roller 62 is 1 to 1.5 times the length in the left-right direction of the region W of the bobbin 14 around which the fiber bundle F is wound. If the length in the left-right direction of the twist suppression roller 62 is too short, the fiber bundle F may fall off the end of the twist suppression roller 62 during traversing, while if it is too long, the bobbin unwinding device 15 becomes large. According to this embodiment, it is possible to prevent the bobbin unwinding device 15 from becoming large, while also preventing the fiber bundle F from falling off the twist suppression roller 62 during traversing.

[0055] Furthermore, in the bobbin unwinding device 15 of this embodiment, the fulcrum guide 61 is a roller member having an axis perpendicular to the axial direction (i.e., the left-right direction) of the bobbin holder 13. According to this embodiment, by hanging the fiber bundle F on the fulcrum guide 61, which is a roller member, the fiber bundle unwound from the bobbin 14 can be twisted by 90 degrees and guided downstream of the fulcrum guide 61.

[0056] Furthermore, in the bobbin unwinding device 15 of this embodiment, the maximum path length X of the fiber bundle F traveling between the fulcrum guide 61 and the downstream guide roller 63b, which is a guide roller 63 arranged immediately upstream of the fulcrum guide 61 in the traveling direction of the fiber bundle F, is 20 to 100 times the width of the fiber bundle F. In this embodiment, the fiber bundle F is configured to be twisted 90 degrees midway from the downstream guide roller 63b to the fulcrum guide 61. In this configuration, the traveling path of a portion of the fiber bundle F in the width direction (hereinafter, the widthwise portion) traveling from the downstream guide roller 63b to the fulcrum guide 61 is approximately linear so as to take the shortest path. On the other hand, the traveling path of the other portion of the fiber bundle F in the width direction (hereinafter, the widthwise portion) cannot take the shortest path and is longer than the traveling path of the widthwise portion. In this situation, the widthwise portion is pulled toward the widthwise portion in an attempt to travel the shortest path, resulting in a narrower width of the fiber bundle. Here, if the distance between the downstream guide roller 63b and the fulcrum guide 61 is increased, the variation in path length between one portion in the width direction and another portion in the width direction is reduced, and the width of the fiber bundle can be prevented from becoming narrower. On the other hand, if the distance between the downstream guide roller 63b and the fulcrum guide 61 is too long, the bobbin unwinding device 15 becomes large. According to this embodiment, it is possible to prevent the bobbin unwinding device 15 from becoming large, while also preventing the width of the fiber bundle F from becoming narrower as it travels from the downstream guide roller 63b toward the fulcrum guide 61.

[0057] Furthermore, in the bobbin unwinding device 15 of this embodiment, for all guide rollers 63, the winding angle at which the fiber bundle F is wound around the guide rollers 63 is 45 degrees or more and 240 degrees or less when viewed from the left-right direction. Accordingly, by setting the winding angle to 45 degrees or more, the fiber bundle F can be tightly wound around the guide rollers 63. This makes it possible to prevent the fiber bundle F from twisting in the left-right direction when the fiber bundle F traverses the circumferential surface of the guide rollers 63 in the left-right direction. In addition, by setting the winding angle to 240 degrees or less, when viewed from the left-right direction, the fiber bundle F wound around the guide rollers 63 is less likely to cross between the upstream and downstream portions of the guide rollers 63. This makes it possible to prevent the portion of the fiber bundle F traveling upstream of the guide rollers 63 and the portion of the fiber bundle F traveling downstream from interfering with each other and becoming entangled.

[0058] Furthermore, in the bobbin unwinding device 15 of this embodiment, for all guide rollers 63, the winding angle at which the fiber bundle F is wound around the guide rollers 63 is 70 degrees or more and 200 degrees or less when viewed from the left-right direction. Accordingly, by setting the winding angle to 70 degrees or more, the fiber bundle F can be wound more firmly around the guide rollers 63. This further prevents the fiber bundle F from twisting in the left-right direction when the fiber bundle F traverses the circumferential surface of the guide rollers 63 in the left-right direction. In addition, by setting the winding angle to 200 degrees or less, it is possible to prevent the fiber bundle F wound around the guide rollers 63 from intersecting between the upstream and downstream portions of the guide rollers 63 when viewed from the left-right direction. This prevents the portion of the fiber bundle F traveling upstream of the guide rollers 63 and the portion of the fiber bundle F traveling downstream from interfering with each other and becoming entangled.

[0059] Furthermore, in the bobbin unwinding device 15 of this embodiment, when viewed from the left-right direction, the winding angle α at which the fiber bundle F is wound around the twist suppression roller 62 is 70 degrees or more and 200 degrees or less. Accordingly, by setting the winding angle to 70 degrees or more, the fiber bundle F can be tightly wound around the twist suppression roller 62. This makes it possible to suppress twisting of the fiber bundle F in the left-right direction when the fiber bundle F traverses the circumferential surface of the twist suppression roller 62 in the left-right direction. In addition, by setting the winding angle to 200 degrees or less, when viewed from the left-right direction, it is possible to prevent the fiber bundle F wound around the twist suppression roller 62 from intersecting with the upstream and downstream portions of the twist suppression roller 62. This makes it possible to prevent the portion of the fiber bundle F traveling upstream of the twist suppression roller 62 and the portion of the fiber bundle F traveling downstream from interfering with each other and becoming entangled.

[0060] (Variation) The following describes modifications of the above embodiment, but the same reference numerals are used to designate components having the same configuration as the above embodiment, and the description thereof will be omitted as appropriate.

[0061] (First Modification) The positions of the fulcrum guide 61, the twist suppression roller 62, and the guide roller 63 are not limited to those of the above embodiment. For example, in the bobbin unwinding device 115 shown in Fig. 7 and Fig. 8, the arrangement of the fulcrum guide 161, the twist suppression roller 162, and the guide roller 163 differs from that of the fulcrum guide 61, the twist suppression roller 62, and the guide roller 63 of the above embodiment. Fig. 7 is a diagram of the bobbin unwinding device 115 as viewed from the left and right. Fig. 8 is a diagram of the bobbin unwinding device 115 as viewed from the top and bottom.

[0062] The fulcrum guide 161 is a roller member having an axis parallel or approximately parallel to the up-down direction, similar to the fulcrum guide 61 of the above embodiment. In the first modified example, the fulcrum guide 161 is disposed on the rear and lower side of the bobbin holder 13 (see FIGS. 7 and 8). The fulcrum guide 61 is also disposed on the lower side near the center in the left-right direction of the bobbin holder 13 (see FIG. 8).

[0063] 7, the twist suppression roller 162 is disposed in the middle of the travel path of the fiber bundle F formed between the bobbin 14 and the fulcrum guide 161. The twist suppression roller 162 is disposed behind and below the bobbin holder 13 (see FIGS. 7 and 8).

[0064] The bobbin unwinding device 115 has three guide rollers 163. As shown in FIG. 7, the three guide rollers 163 are arranged in the middle of the running path of the fiber bundle F formed between the torsion suppression roller 162 and the fulcrum guide 161. The three guide rollers 163 are composed of a first guide roller 163a, a second guide roller 163b, and a third guide roller 163c. The first guide roller 163a is arranged on the most upstream side of the three guide rollers 163 in the running direction of the fiber bundle F. The third guide roller 163c is arranged on the most downstream side of the three guide rollers 163 in the running direction of the fiber bundle F. The second guide roller 163b is arranged between the first guide roller 163a and the third guide roller 163c in the running direction of the fiber bundle F.

[0065] The first guide roller 163a is disposed above and behind the bobbin holder 13 (see FIGS. 7 and 8). Furthermore, the axis of the first guide roller 163a is slightly behind the axis of the twist suppression roller 162 (see FIG. 7). The second guide roller 163b is disposed above and in front of the bobbin holder 13 (see FIGS. 7 and 8). Furthermore, the axis of the second guide roller 163b is slightly above the axis of the first guide roller 163a (see FIG. 7). The third guide roller 163c is disposed below and in front of the bobbin holder 13 (see FIGS. 7 and 8). Furthermore, the third guide roller 163c is disposed below the twist suppression roller 162 (see FIG. 7).

[0066] In the bobbin unwinding device 115 described above, the fiber bundle F unwound from the bobbin 14 is fed to the fulcrum guide 161 so as to make approximately one full revolution around the bobbin 14 when viewed from the left-right direction. Here, in the first modified example, the winding angle at which the fiber bundle F is wound around the torsion suppression roller 162 is preferably 70 degrees or more and 200 degrees or less. The winding angle E1 at which the fiber bundle F is wound around the torsion suppression roller is, for example, approximately 150 degrees. However, the winding angle E1 may vary slightly depending on the amount of the fiber bundle F. Furthermore, for the three guide rollers 163, when viewed from the left-right direction, the winding angle at which the fiber bundle F is wound around the guide rollers 163 is preferably 20 degrees or more and 280 degrees or less, more preferably 45 degrees or more and 240 degrees or less, and most preferably 70 degrees or more and 200 degrees or less. The winding angle E2 at which the fiber bundle F is wound around the first guide roller 163a is, for example, approximately 90 degrees. The winding angle E3 at which the fiber bundle F is wound around the second guide roller 163b is, for example, approximately 90 degrees. The winding angle E4 at which the fiber bundle F is wound around the third guide roller 163c is, for example, approximately 90 degrees. Furthermore, the maximum path length of the fiber bundle F traveling between the third guide roller 163c and the fulcrum guide 161 is preferably 20 to 100 times the width of the fiber bundle F. Furthermore, the length in the left-right direction of the twist suppression roller 162 is preferably 1 to 1.5 times the length in the left-right direction of the region W of the bobbin 14 around which the fiber bundle F is wound.

[0067] (Second Modification) Another example of the arrangement of the fulcrum guide, twist suppression roller, and guide rollers will be described below. As shown in Fig. 9, a bobbin unwinding device 215 according to a second modified example has a fulcrum guide 261, a twist suppression roller 262, and five guide rollers 263. Fig. 9 is a diagram of the bobbin unwinding device 215 according to the second modified example as viewed from the left and right.

[0068] The fulcrum guide 261 is a roller member having an axis that is approximately parallel to the vertical direction. However, the axis direction of the fulcrum guide 261 is not limited to this. The fulcrum guide 261 is disposed below the bobbin holder 13.

[0069] 9, the twist suppression roller 262 is disposed midway along the travel path of the fiber bundle F formed between the bobbin 14 and the fulcrum guide 261. The twist suppression roller 262 is disposed in front of and above the bobbin holder 13 (see FIG. 9). The winding angle Z1 at which the fiber bundle F is wound around the twist suppression roller 262 is, for example, 98 degrees.

[0070] The five guide rollers 263 are arranged in the middle of the travel path of the fiber bundle F formed between the torsion suppression roller 262 and the fulcrum guide 261. In the travel direction of the fiber bundle F, the first guide roller 263a, the second guide roller 263b, the third guide roller 263c, the fourth guide roller 263d, and the fifth guide roller 263e are arranged in this order from upstream to downstream. The winding angle Z2 at which the fiber bundle F is wound around the first guide roller 263a is, for example, 20 degrees. The winding angle Z3 at which the fiber bundle F is wound around the second guide roller 263b is, for example, 80 degrees. The winding angle Z4 at which the fiber bundle F is wound around the third guide roller 263c is, for example, 90 degrees. The winding angle Z5 at which the fiber bundle F is wound around the fourth guide roller 263d is, for example, 260 degrees. The winding angle Z6 at which the fiber bundle F is wound around the fifth guide roller 263e is, for example, 260 degrees. The first guide roller 263a and the second guide roller 263b are disposed above the bobbin holder 13, and the third guide roller 263c, the fourth guide roller 263d and the fifth guide roller 263e are disposed below the bobbin holder 13.

[0071] The first guide roller 263a is disposed slightly above the twist suppression roller 262 and the second guide roller 263b (see FIG. 9). By disposing them in this manner, when the fiber bundle F traveling between the twist suppression roller 262 and the second guide roller 263b becomes slack, the first guide roller 263a can prevent the fiber bundle F from coming into contact with the bobbin 14.

[0072] (Third Modification) As shown in Fig. 10, a bobbin unwinding device 315 according to the third modified example has a fulcrum guide 361, a twist suppression roller 362, and four guide rollers 363. Fig. 10 is a diagram of the bobbin unwinding device according to the third modified example when viewed from the left and right.

[0073] The fulcrum guide 361 is a roller member having an axis that is approximately parallel to the vertical direction. However, the axis direction of the fulcrum guide 361 is not limited to this. The fulcrum guide 361 is disposed below the bobbin holder 13.

[0074] 10, the twist suppression roller 362 is disposed in the middle of the travel path of the fiber bundle F formed between the bobbin 14 and the fulcrum guide 361. The twist suppression roller 362 is disposed behind the bobbin holder 13 (see FIG. 10). The winding angle Z11 at which the fiber bundle F is wound around the twist suppression roller 362 is, for example, 91 degrees.

[0075] The four guide rollers 363 are arranged in the middle of the travel path of the fiber bundle F formed between the torsion suppression roller 362 and the fulcrum guide 361. In the travel direction of the fiber bundle F, the first guide roller 363a, the second guide roller 363b, the third guide roller 363c, and the fourth guide roller 363d are arranged in this order from upstream to downstream. The winding angle Z12 at which the fiber bundle F is wound around the first guide roller 363a is, for example, 85 degrees. The winding angle Z13 at which the fiber bundle F is wound around the second guide roller 363b is, for example, 149 degrees. The winding angle Z14 at which the fiber bundle F is wound around the third guide roller 363c is, for example, 189 degrees. The winding angle Z15 at which the fiber bundle F is wound around the fourth guide roller 363d is, for example, 190 degrees. The first guide roller 363a, the second guide roller 363b, and the fourth guide roller 363d are disposed on the rear side of the bobbin holder 13, and the third guide roller 363c is disposed on the front side of the bobbin holder 13. All four guide rollers 363 are disposed below the bobbin holder 13.

[0076] In the configuration of the third modified example, for all of the four guide rollers 363, the winding angle at which the fiber bundle F is wound around the guide rollers 363 is equal to or greater than 70 degrees and equal to or less than 200 degrees.

[0077] (Fourth Modification) In the above embodiment, the bobbin unwinding device 15 is a device for unwinding the fiber bundle F from the bobbin 14 supported by the bobbin holder 13 provided on the creel stand 3, and the unwound fiber bundle F is supplied to the helical winding unit 50. However, the bobbin unwinding device may be a device for unwinding the fiber bundle F from a bobbin supported by a bobbin holder 43 provided on the hoop winding unit 40. Below, a bobbin unwinding device for unwinding the fiber bundle F from a bobbin supported by a bobbin holder 43 provided on the hoop winding unit 40 will be described.

[0078] The bobbin unwinding device 415 according to the fourth modified example is a device for unwinding a fiber bundle F from a bobbin 114 supported by, for example, a bobbin holder 43 (see also FIG. 1) attached to a rotating member 42 of a hoop winding unit 40. As shown in FIG. 11, the bobbin unwinding device 415 has a fulcrum guide 461, a twist suppression roller 462, and one guide roller 463. FIG. 11 is a diagram of the bobbin unwinding device according to the fourth modified example when viewed from the front-rear direction.

[0079] The fulcrum guide 461 is a guide that serves as a fulcrum when the fiber bundle F traverses in the axial direction (front-rear direction) of the bobbin holder 43. The fulcrum guide 461 is a roller member having an axis that is approximately parallel to the up-down direction. However, the fulcrum guide 461 may be, for example, a U-shaped guide around which the fiber bundle F is hung. In the fourth modified example, the width direction of the fiber bundle F immediately after being unwound from the bobbin 114 is the front-rear direction, and the width direction of the fiber bundle F wound around the circumferential surface of the fulcrum guide 461 is the up-down direction. As shown in FIG. 11 , the fulcrum guide 461 is disposed on the left and lower side of the bobbin holder 43.

[0080] As shown in Fig. 11, the twist suppression roller 462 is disposed in the middle of the travel path of the fiber bundle F formed between the bobbin 114 and the fulcrum guide 461. The twist suppression roller 462 is disposed to the right and below the bobbin holder 43 (see Fig. 11). The twist suppression roller 462 has an axis that is approximately parallel to the front-rear direction. The winding angle Z21 at which the fiber bundle F is wound around the twist suppression roller 462 is, for example, 80 degrees.

[0081] The guide roller 463 is disposed midway along the travel path of the fiber bundle F formed between the twist suppression roller 462 and the fulcrum guide 461. The guide roller 463 is disposed below and slightly to the left of the twist suppression roller. The winding angle Z22 at which the fiber bundle F is wound around the guide roller 463 is, for example, 140 degrees.

[0082] Compared to the case where the bobbin unwinding device 15 is provided in the creel stand 3 as in the above embodiment, the bobbin unwinding device 415 provided in the hoop winding unit 40 has a limited space for unwinding the fiber bundle F. For this reason, as shown in Fig. 11 , in the bobbin unwinding device 415 according to the fourth modified example, the twist suppression roller 462 and the guide roller 463 are positioned close to each other.

[0083] (Fifth Modification) A bobbin unwinding device for unwinding a fiber bundle F from a bobbin supported by a bobbin holder 43 provided in the hoop winding unit 40, which has a configuration different from that of the fourth modified example, will be described below. As shown in Fig. 12, a bobbin unwinding device 515 according to the fifth modified example has a fulcrum guide 561, a twist suppression roller 562, and two guide rollers 563. Fig. 12 is a view of the bobbin unwinding device according to the fifth modified example as viewed from the front-rear direction.

[0084] The fulcrum guide 561 is a guide that serves as a fulcrum when the fiber bundle F traverses in the axial direction (front-rear direction) of the bobbin holder 43. The fulcrum guide 561 is a roller member having an axis that is approximately parallel to the up-down direction. However, the fulcrum guide 561 may be, for example, a U-shaped guide around which the fiber bundle F is hung. In the fifth modified example, the width direction of the fiber bundle F immediately after being unwound from the bobbin 114 is the front-rear direction, and the width direction of the fiber bundle F wound around the circumferential surface of the fulcrum guide 561 is the up-down direction. As shown in FIG. 12 , the fulcrum guide 561 is disposed on the left and lower side of the bobbin holder 43.

[0085] As shown in Fig. 12, the twist suppression roller 562 is disposed in the middle of the travel path of the fiber bundle F formed between the bobbin 114 and the fulcrum guide 561. The twist suppression roller 562 is disposed on the right side of the bobbin holder 43 (see Fig. 12). The twist suppression roller 562 has an axis that is approximately parallel to the front-rear direction. The winding angle Z31 at which the fiber bundle F is wound around the twist suppression roller 562 is, for example, 95 degrees.

[0086] The guide roller 563 is disposed midway along the travel path of the fiber bundle F formed between the torsion suppression roller 562 and the fulcrum guide 561. In the travel direction of the fiber bundle F, a first guide roller 563a and a second guide roller 563b are disposed in this order from upstream to downstream. The first guide roller 563a and the second guide roller 563b are disposed below and to the right of the bobbin holder 43. The first guide roller 563a is disposed above the second guide roller 563b. The winding angle Z32 at which the fiber bundle F is wound around the first guide roller 563a is, for example, 80 degrees. The winding angle Z33 at which the fiber bundle F is wound around the second guide roller 563b is, for example, 139 degrees.

[0087] In the configuration of the fifth modified example, the winding angle at which the fiber bundle F is wound around each of the two guide rollers 563 is 70 degrees or more. Therefore, compared to the fourth modified example, it is possible to suppress twisting of the fiber bundle F wound around the guide roller 563 in the left-right direction.

[0088] (Other variations) The bobbin unwinding device 15 of the above embodiment is provided with two guide rollers 63. However, the number of guide rollers 63 provided in the bobbin unwinding device may be one, or three or more.

[0089] In the above embodiment, the fulcrum guide 61 is a roller member having an axis parallel to the up-down direction. However, the axis direction of the fulcrum guide 61 is not limited to the up-down direction. For example, the fulcrum guide 61 may have an axis approximately parallel to the front-rear direction or the left-right direction. Furthermore, the fulcrum guide 61 is not limited to a roller member. The fulcrum guide 61 may be any guide that serves as a fulcrum when the fiber bundle F traverses in the front-rear direction, and may be, for example, a U-shaped or V-shaped member around which the fiber bundle F is hung.

[0090] In the above embodiment, the left-right length of the twist suppression roller 62 is approximately the same as the left-right length of the guide roller 63. However, the left-right length of the guide roller 63 may be shorter than the left-right length of the twist suppression roller 62.

[0091] In the present invention, the diameter of the bobbin holder, the diameter of the fulcrum guide, the diameter of the twist suppression roller, and the diameter of the guide roller are not particularly limited. [Explanation of symbols]

[0092] 1 Filament winding device 13 Bobbin holder (bobbin support shaft) 14 bobbins 15 Bobbin unwinding device 61 Fulcrum Guide 62 Torsion suppression roller 63 Guide roller 63a Upstream guide roller 63b Downstream guide roller (most downstream guide roller) F fiber bundle W area α Wrapping angle β Wrapping angle γ Wrapping angle θ Pull-out angle

Claims

1. a bobbin support shaft that rotatably supports a bobbin around which a fiber bundle is wound; a fulcrum guide around which the fiber bundle unwound from the bobbin is hung and which serves as a fulcrum when the fiber bundle is traversed in the axial direction of the bobbin support shaft; a twist suppression roller having an axis parallel to the axial direction and disposed midway along a travel path of the fiber bundle formed between the bobbin and the fulcrum guide; At least one guide roller having an axis parallel to the axial direction and arranged in the middle of a travel path of the fiber bundle formed between the torsion suppression roller and the fulcrum guide; Equipped with The guide roller is configured so that the fiber bundle traverses the peripheral surface of the guide roller in the axial direction, and the bobbin unwinding device is disposed at a position deviated from the shortest path connecting the torsion suppression roller and the fulcrum guide when viewed from the axial direction.

2. The bobbin unwinding device according to claim 1 , wherein the length of the twist suppression roller in the axial direction is 1 to 1.5 times the length of the region of the bobbin around which the fiber bundle is wound in the axial direction.

3. 3. The bobbin unwinding device according to claim 1, wherein the fulcrum guide is a roller member having an axis perpendicular to the axial direction.

4. 4. The bobbin unwinding device according to claim 3, wherein a maximum path length of the fiber bundle traveling between the fulcrum guide and the most downstream guide roller, which is the guide roller arranged immediately upstream of the fulcrum guide in the traveling direction of the fiber bundle, is 20 to 100 times the width of the fiber bundle.

5. 3. The bobbin unwinding device according to claim 1, wherein the winding angle of the fiber bundle around each of the guide rollers is 45 degrees or more and 240 degrees or less when viewed from the axial direction for all of the guide rollers.

6. 6. The bobbin unwinding device according to claim 5, wherein the winding angle of the fiber bundle around each of the guide rollers is 70 degrees or more and 200 degrees or less when viewed from the axial direction for all of the guide rollers.

7. 3. The bobbin unwinding device according to claim 1, wherein the fiber bundle is wound around the twist suppression roller at a winding angle of 70 degrees or more and 200 degrees or less when viewed from the axial direction.

8. 4. The bobbin unwinding device according to claim 3, wherein the fiber bundle is wound around the twist suppression roller at a winding angle of 70 degrees or more and 200 degrees or less when viewed in the axial direction.

9. 5. The bobbin unwinding device according to claim 4, wherein the fiber bundle is wound around the twist suppression roller at a winding angle of 70 degrees or more and 200 degrees or less when viewed in the axial direction.

10. The bobbin unwinding device according to claim 5, wherein the fiber bundle is wound around the twist suppression roller at a winding angle of 70 degrees or more and 200 degrees or less when viewed in the axial direction.

11. The bobbin unwinding device according to claim 6, wherein the fiber bundle is wound around the twist suppression roller at a winding angle of 70 degrees or more and 200 degrees or less when viewed in the axial direction.

Images