Filament winding apparatus

Abstract

A filament winding apparatus includes: a rotation device that rotates a workpiece; and a guide unit that is movable in an axial direction parallel to a rotation axis of the workpiece and that guides a fiber bundle to be fed to the workpiece on the rotation device. The guide unit includes a first roller that guides the fiber bundle, and a first adjustment mechanism configured to adjust a distance between the first roller and the workpiece. The filament winding apparatus includes a control unit that controls operation of the first adjustment mechanism. The control unit moves the first roller away from a surface of the workpiece in a predetermined first process of a series of winding processes, and brings the first roller into contact with the surface of the workpiece with the fiber bundle therebetween in a predetermined second process of the series of winding processes.

Description

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to Japanese Patent Application No. 2024-114252 filed on Jul. 17, 2024. The disclosure of the above-identified application, including the specification, drawings, and claims, is incorporated by reference herein in its entirety.BACKGROUND1. Technical Field

[0002] The technique disclosed herein relates to filament winding apparatuses.2. Description of Related Art

[0003] Japanese Unexamined Patent Application Publication No. 2020-139581 (JP 2020-139581 A) describes a filament winding apparatus that can perform a winding process. In the winding process, a fiber bundle is wound around a workpiece by bringing the fiber bundle into close contact with the periphery of the workpiece while holding the fiber bundle under tension.SUMMARY

[0004] There is a case where a fiber bundle cannot be brought into sufficiently close contact with the surface of a workpiece and a protruding portion is formed during a series of winding processes. For example, when the winding pattern is changed between helical winding and hoop winding etc., a protruding portion may be formed due to a decrease in tension applied to a fiber bundle. In another example, when the winding pattern is changed, a protruding portion may be formed due to fiber crossovers being formed due to an asymmetrical, irregular winding method. The protruding portion causes undulation (bending) when the fiber bundle is placed on the previous layer in the subsequent step. Fiber strength may decrease in the bent portion, which may result in reduced fatigue performance.

[0005] A filament winding apparatus disclosed in the present specification includes a rotation device configured to rotate a workpiece.

[0006] The filament winding apparatus includes a guide unit that is movable in an axial direction parallel to a rotation axis of the workpiece. The guide unit is configured to guide a fiber bundle to be fed to the workpiece on the rotation device.

[0007] The guide unit includes a first roller configured to guide the fiber bundle, and a first adjustment mechanism configured to adjust a distance between the first roller and the workpiece.

[0008] The filament winding apparatus includes a control unit configured to control operation of the first adjustment mechanism.

[0009] The control unit is configured to move the first roller away from a surface of the workpiece in a predetermined first process of a series of winding processes, and is configured to bring the first roller into contact with the surface of the workpiece with the fiber bundle between the first roller and the surface of the workpiece in a predetermined second process of the series of winding processes.

[0010] With the above configuration, the first roller can be moved away from the surface of the workpiece in the predetermined first process. This can reduce various resistances that are generated by the first roller, and can thus increase the winding speed. Moreover, the fiber bundle can be pressed against the surface of the workpiece by the first roller in the second process. The fiber bundle can thus be brought into sufficiently close contact with the surface of the workpiece, so that a step at a protruding portion can be minimized. It is therefore possible to reduce a decrease in fatigue performance while maintaining the throughput of the winding process.BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Features, advantages, and technical and industrial significance of exemplary embodiments of the disclosure will be described below with reference to the accompanying drawings, in which like signs denote like elements, and wherein:

[0012] FIG. 1 is a side view of an FW apparatus 1 with a first roller 11 located at a contact position;

[0013] FIG. 2 is a top view of the FW apparatus 1 with the first roller 11 located at the contact position;

[0014] FIG. 3 is a side view of the FW apparatus 1 with the first roller 11 located at a separate position;

[0015] FIG. 4 is a side view of the FW apparatus 1 with a second roller 12 and a third roller 13 in a fixed state;

[0016] FIG. 5A is a diagram illustrating a type of winding process;

[0017] FIG. 5B is a diagram illustrating a type of winding process;

[0018] FIG. 5C is a diagram illustrating a type of winding process; and

[0019] FIG. 6 is a flowchart illustrating the operation of the FW apparatus 1.DETAILED DESCRIPTION OF EMBODIMENTS

[0020] Additional features of the filament winding apparatus disclosed herein are listed below.

[0021] In one embodiment of the present technology,

[0022] The first process may include performing helical winding and performing hoop winding.

[0023] The second process may include switching between helical winding and hoop winding.

[0024] According to the above configuration, in the first process, the processing speed of the helical winding and the hoop winding can be increased. In the second process, the fiber bundle can be pressed against the surface of the workpiece by the first roller. It is possible to minimize a step at a protruding portion that is formed when the winding method is switched.

[0025] In one embodiment of the present technology,

[0026] The guide unit may further include a second roller and a third roller disposed farther from the workpiece than the first roller and opposed to each other and passing the fiber bundle between the rollers.

[0027] The guide unit may further include a second adjustment mechanism configured to adjust a distance between the second roller and the third roller.

[0028] The guide unit may further include a cutting mechanism arranged on the feed path for the fiber bundle from the second roller and the third roller to the first roller.

[0029] The second adjustment mechanism may be able to change a state between a fixed state in which the second roller and the third roller are in contact with each other via the fiber bundle, and a non-fixed state in which the second roller and the third roller are separated from each other.

[0030] The control unit may set the second roller and the third roller to the non-fixed state during the series of winding processes.

[0031] In an end process for ending the series of winding processes, the control unit may stop rotating the workpiece, set the second roller and the third roller to the fixed state, and cut the fiber bundle by the cutting mechanism.

[0032] According to the above configuration, the fiber bundle can be cut while the fiber bundle is held in a fixed state by sandwiching the fiber bundle by the second roller and the third roller. Since the fiber bundle can be cut in a state in which tension is applied to the fiber bundle, it is possible to reliably cut.

[0033] In one embodiment of the present technology,

[0034] In the end process, the control unit may bring the first roller into contact with the surface of the workpiece with the fiber bundle therebetween before cutting the fiber bundle.

[0035] In the end process, the control unit may rotate the workpiece so as to cause the first roller to pass on the cut end of the fiber bundle with the first roller being in contact with the fiber bundle after cutting the fiber bundle.

[0036] According to the above configuration, the cut end of the fiber bundle can be pressed against the surface of the workpiece by the first roller. A step at a protruding portion that is formed at the cut end of the fiber bundle can be minimized.

[0037] In an embodiment of the present technology, the first adjustment mechanism may be configured to be capable of changing a relative position of the first roller with respect to the housing of the guide unit.First EmbodimentSchematic configuration of Filament Winding Apparatus 1

[0038] FIGS. 1 to 3 show a schematic configuration of a filament winding apparatus 1 (sometimes simply referred to as FW apparatus 1) of the present embodiment. FIG. 1 is a side view of the first roller 11 in a contact position. FIG. 2 is a top view of FIG. 1. FIG. 3 is a side view in a state in which the first roller 11 is located at a separate position. For the sake of clarity, the configurations of the upper portion of the housing 15, the first adjustment mechanism 20, the second adjustment mechanism 30, the third roller 13, etc. are not shown in FIG. 2. The FW apparatus 1 is a device that winds the resin-impregnated fiber bundle 70 around the workpiece 60 while applying tension. The fiber bundle 70 is obtained by impregnating a thermosetting epoxy resin with a fiber bundle, for example.

[0039] The FW apparatus 1 mainly includes a guide unit 10, a control unit 50, and a rotation device 61. As shown in FIG. 2, the rotation device 61 is a device that rotatably fixes the workpiece 60. The workpiece 60 is a cylindrical hollow container. The workpiece 60 has a gas barrier property and is filled with a high-pressure gas such as hydrogen. The workpiece 60 includes a cylindrical body portion 60b and a pair of dome portions 60d. The pair of dome portions 60d is connected to both ends of the body portion 60b. The workpiece 60 includes a rotation axis RA. The rotation device 61 rotates the workpiece 60 about the rotation axis RA.

[0040] The guide unit 10 is a mechanism for guiding the fiber bundle 70 supplied to the workpiece 60. The guide unit 10 is also referred to as an eye, a feed eye, or the like. The guide unit 10 is movable along an axial direction (y-axis direction) parallel to the rotation axis RA of the workpiece 60, and is movable along a front-rear axis (x-axis direction).

[0041] The guide unit 10 mainly includes a first roller 11, a second roller 12, a third roller 13, a fourth roller 14, a housing 15, a first adjustment mechanism 20, a second adjustment mechanism 30, and a cutting mechanism 40. The first roller 11 to the fourth roller 14 are rollers that guide the fiber bundle 70. The first roller 11 to the fourth roller 14 are rotatably supported by a support shaft, not shown, and are arranged parallel to each other. The first roller 11 is disposed on the distal end side of the guide unit 10. The second roller 12 and the third roller 13 are disposed farther away from the workpiece 60 than the first roller 11. The second roller 12 and the third roller 13 are disposed so as to face each other, and the fiber bundle 70 passes between the rollers. In the present embodiment, the fiber bundle 70 enters from the fourth roller 14 side, contacts the lower outer periphery of the fourth roller 14, the upper outer periphery of the second roller 12, and the lower outer periphery of the first roller 11, and is supplied to the workpiece 60.

[0042] The first adjustment mechanism 20 includes an actuator 21, a rack 22, a pinion 23, and a roller support portion 24. In the present embodiment, the actuator 21 is a cylinder. The cylinder may be a pneumatic, hydraulic, or electric cylinder. The actuator 21 moves the pinion 23 in the moving direction D1. The pinion 23 moves linearly on the rack 22. One end of the roller support portion 24 is fixed to the pinion 23. The first roller 11 is rotatably supported at the other end of the roller support portion 24.

[0043] The first adjustment mechanism 20 is a mechanism that can adjust the distance between the first roller 11 and the workpiece 60. In other words, the first adjustment mechanism 20 can change the relative position of the first roller 11 with respect to the housing 15. This will be specifically described. The first adjustment mechanism 20 can change the position of the first roller 11 between the contact position (FIG. 1) and the separate position (FIG. 3). The contact position in FIG. 1 is a position where the first roller 11 is in contact with the surface of the workpiece 60 with the fiber bundle 70 therebetween. The separate position in FIG. 3 is a position in which the first roller 11 is located away from the surface of the workpiece 60.

[0044] The second adjustment mechanism 30 is an actuator. In the present embodiment, the second adjustment mechanism 30 is a cylinder. The second adjustment mechanism 30 moves the third roller 13 in the moving direction D2. The second adjustment mechanism 30 is a mechanism that can adjust the distance between the second roller 12 and the third roller 13. That is, the second adjustment mechanism can change the second roller 12 and the third roller 13 between the non-fixed state (FIGS. 1 and 3) and the fixed state (FIG. 4). In the non-fixed state (FIGS. 1 and 3), the second roller 12 and the third roller 13 are separated from each other. The fixed state (FIG. 4) is a state in which the second roller 12 and the third roller 13 are in contact with each other with the fiber bundle 70 therebetween. In other words, the fixed state is a state in which the fiber bundle 70 is clamped and fixed by the second roller 12 and the third roller 13.

[0045] The cutting mechanism 40 is disposed on the feed path for the fiber bundle 70 between the second roller 12 and third roller 13 and the first roller 11. As shown in FIG. 2, the cutting mechanism 40 includes a cutter 41 and a rail 42. The rail 42 is disposed in a direction (y direction) perpendicular to the supply direction (x direction) of the fiber bundle 70. The cutter 41 is configured to be movable on the rail 42 by an actuator, not shown (see arrow Y1). The cutter 41 is separated from the feed path of the fiber bundle 70 in the retracted position of FIG. 2. The fiber bundle 70 can then be cut by the cutter 41 moving the rail 42 in Y1 of the arrow.

[0046] The control unit 50 is a part that controls operations of the first adjustment mechanism 20, the second adjustment mechanism 30, the cutting mechanism 40, the rotation device 61, and the like. The control unit 50 may be configured as a computer including a CPU and memories. Various mechanisms may be controlled by the CPU executing a control program stored in the memory.Content of Each Winding Process

[0047] A series of winding processes are performed by winding a continuous fiber bundle 70 around the workpiece 60. The series of winding processes includes a first process and a second process. The first process is a process of performing helical winding and hoop winding. Helical winding is a process in which the fiber bundle 70 is wound in a spiral shape in the rotation axis RA as shown in FIG. 5A. In other words, the helical winding is a winding method in which the angle with respect to the rotation axis RA is a relatively low angle, and is a winding method in which the helical winding is applied to the pair of dome portions 60d. As shown in FIG. 5C, the hoop winding is a process of winding the fiber bundle 70 around the body portion 60b. In other words, the hoop winding is a winding method in which the angle with respect to the rotation axis RA is a relatively high angle, and is a winding method in which the hoop winding is not applied to the pair of dome portions 60d. Note that the hoop winding in the present specification includes a so-called high-angle helical winding.

[0048] The second process is a process of switching between helical winding and hoop winding. In the present embodiment, in the second process, the combination winding shown in FIG. 5B is performed. Combination winding is a winding method for raising an angle with respect to the rotation axis RA from a low angle state (helical winding) to a high angle state (hoop winding). The combination winding has a threading path that passes in sequence from the position P1 to the position P6. The position P1 is the end point position of the helical winding. The position P6 is the starting position of the hoop winding. Since the combination winding is an asymmetrical, irregular winding method, a plurality of protruding portions is formed on the surface of the workpiece 60.Operation of FW Apparatus 1

[0049] The operation of the FW apparatus 1 will be described with reference to the flowchart of FIG. 6. The FW apparatus 1 performs a starting process (S5), a series of winding processes (S10 to S50), and an end process (S60 to S130).

[0050] Prior to performing S5, the distal end of the fiber bundle 70 is set on the first roller 11. The content of setting the distal end of the fiber bundle 70 will be described later in S130.

[0051] In S5, the first adjustment mechanism 20 moves the position of the first roller 11 to the contact position (FIG. 1). As a result, the distal end of the fiber bundle 70 can be pressed against the surface of the workpiece 60 by the first roller 11.

[0052] Next, the winding processes (S10 to S50) will be described. During the winding process, the second roller 12 and the third roller 13 are kept in the non-fixed state.

[0053] In S10, the first adjustment mechanism 20 moves the position of the first roller 11 to the separate position (FIG. 3). The first roller 11 is thus located away from the surface of the workpiece 60. In S15, the control unit 50 performs the first process (helical winding) (see FIG. 5A). The first process is performed with the first roller 11 located at the separate position (FIG. 3). Once helical placement is complete, the process proceed to S20.

[0054] In S20, the first adjustment mechanism 20 moves the position of the first roller 11 to the contact position (FIG. 1). As a result, the first roller 11 comes into contact with the surface of the workpiece 60 with the fiber bundle 70 therebetween. The first roller 11 may be moved while the workpiece 60 is rotated, or the first roller 11 may be moved after the rotation of the workpiece 60 is stopped.

[0055] In S30, the control unit 50 performs the second process (combination winding) (see FIG. 5B). The combination winding process is performed in a state where the position of the first roller 11 is set to the contact position (FIG. 1). When the fiber bundle 70 is wound up to the position P6 in FIG. 5B, the process proceeds to S40.

[0056] In S40, the first adjustment mechanism 20 moves the first roller 11 to the separate position (FIG. 3). In S50, the control unit 50 performs the first process (hoop winding) (see FIG. 5C). The first process is performed with the first roller 11 located at the separate position (FIG. 3). Then, when placement of all the layers is completed, the process proceeds to S60.

[0057] The end process (S60 to S130) will be described. In S60, the control unit 50 stops the workpiece 60 from rotating. In S70, the first adjustment mechanism 20 moves the position of the first roller 11 to the contact position (FIG. 1).

[0058] In S80, the second adjustment mechanism 30 moves the third roller 13 toward the second roller 12. As a result, the fiber bundle 70 can be held in the fixed state by the second roller 12 and the third roller 13 (see area A1 in FIG. 4).

[0059] In S90, the cutting mechanism 40 cuts the fiber bundle 70 by moving the cutter 41 across the fiber bundle 70 (see arrow Y1 in FIG. 2). At this time, the fiber bundle 70 on the distal end side (−x direction side) of the cutter 41 is pressed against and fixed to the workpiece 60 by the first roller 11 (see area A2 in FIG. 4). The fiber bundle 70 on the root side (+x direction side) of the cutter 41 is clamped and fixed to the second roller 12 and the third roller 13 (see area A1). Therefore, the fiber bundle 70 can be cut in a state where tension is applied to the fiber bundle 70. Since the cutter 41 can be prevented from escaping, cutting can be reliably performed.

[0060] FIG. 4 shows the state of the fiber bundle 70 after cutting. The cut end 70e and the distal end 70t are formed in the fiber bundle 70 after the cut. The cut end 70 e is located on the workpiece 60. The distal end 70t is clamped and fixed by the second roller 12 and the third roller 13.

[0061] In S100, the control unit 50 performs a process of pressure-bonding the cut end 70e to the surface of the workpiece 60. Specifically, the workpiece 60 is rotated in the rotation direction R1 from the state shown in FIG. 4. This allows the first roller 11 to pass through the upper surface of the cut end 70e while contacting the fiber bundle 70. Since the first roller 11 can pressure-bond the cut end 70e, curling of the cut end 70e can be reduced.

[0062] In S110, the first adjustment mechanism 20 moves the first roller 11 to the separate position (FIG. 3). In S120, the control unit 50 blows hot air to the cut end 70e by a hot air blower, not shown. Accordingly, the cut end 70e can be securely fixed to the front face of the workpiece 60. Note that this step may be skipped.

[0063] In S 130, a process of setting the distal end 70t to the first roller 11 is executed. Specifically, the control unit 50 rotates the second roller 12 and the third roller 13 in a state where the fiber bundle 70 is sandwiched therebetween. As a result, the distal end 70t of the fiber bundle 70 can be fed to the first roller 11. Therefore, S5 of the subsequent winding process can be executed. Since the winding processing can be continuously performed, the winding processing process can be automated. Throughput can be improved, and manufacturing cost can be reduced.Effects

[0064] The problem is described. There is a case where the fiber bundle 70 cannot be brought into sufficiently close contact with the surface of the workpiece 60 and a protruding portion is formed during a series of winding processes. For example, when the winding pattern is changed between helical winding and hoop winding etc., a protruding portion may be formed due to a decrease in tension applied to the fiber bundle 70. In another example, when the winding pattern is changed, a protruding portion may be formed due to fiber crossovers being formed due to an asymmetric, irregular winding method (combination winding). The protruding portion causes undulation (bending) when the fiber bundle is placed on the previous layer in the subsequent step. Fiber strength may decrease in the bent portion, which may result in reduced fatigue performance.

[0065] Therefore, in the technology of the present specification, the first roller 11 can be moved away from the surface of the workpiece 60 in a predetermined first process (helical winding and hoop winding). As a result, various resistances generated by the first roller 11 can be reduced, and thus the winding speed can be increased. Further, in a predetermined second process (combination winding), the fiber bundle 70 can be wound while the fiber bundle 70 is pressed against the surface of the workpiece 60 by the first roller 11. As a result, the fiber bundle 70 can be brought into sufficiently close contact with the surface of the workpiece 60, so that a step at a protruding portion can be minimized. It is possible to reduce a decrease in fatigue performance while maintaining the throughput of the winding process.Second Embodiment

[0066] The second embodiment is different from the first embodiment in that the second process (combination winding) can be omitted. Only the differences from the first embodiment will be described below.

[0067] In the flowchart of FIG. 6, when the first process (helical winding) of S15 is completed, an end process is performed. The content of the end process has been described in S60 to S130 of the first embodiment.

[0068] Next, the guide unit 10 is moved to the hoop winding starting position (see position P6 in FIG. 5B). Then, a start process is performed. The content of the starting process has been described in S5 of the first embodiment. Then, a first process (hoop winding) of S50 is performed. Since the subsequent processes are the same as in the first embodiment, the description thereof will not be repeated.

[0069] In the technique of the second embodiment, the second process (combination winding) of switching between helical winding and hoop winding can be omitted. Since the asymmetrically, irregularly wound layers can be eliminated, it is possible to reduce formation of protruding portions. The fatigue performance can be further improved.

[0070] Although the embodiments have been described in detail above, these are merely examples and do not limit the scope of the claims. The technique described in the claims includes various modifications and variations of the specific examples exemplified above. The technical elements described in the present specification or in the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing the application. In addition, the technique exemplified in the present specification or drawings can achieve a plurality of purposes at the same time, and achieving one of the purposes itself has technical usefulness.Modification

[0071] The process of winding the fiber bundle 70 with the first roller 11 located at the contact position (FIG. 1) is not limited to the second process (combination winding). The present disclosure can be applied to any process as long as it is a process in which it is necessary to reduce fiber undulation and increase the quality of fiber layers. For example, the first roller 11 may be brought into contact with the very first winding start portion (also referred to as three-circuit) of the fiber bundle 70.

[0072] The mechanism for moving the first roller 11 to the contact position is not limited to the first adjustment mechanism 20, and may be various mechanisms. For example, the guide unit 10 itself may move.

[0073] The actuators included in the first adjustment mechanism 20 and the second adjustment mechanism 30 may be various mechanisms. For example, a linear motion system, a ball screw, or the like may be used.

[0074] The cutting mechanism 40 may be a variety of mechanisms. For example, the cutter 41 may be moved in a direction (z direction) perpendicular to the surface of the fiber bundle 70.

Examples

first embodiment

Schematic configuration of Filament Winding Apparatus 1

[0038]FIGS. 1 to 3 show a schematic configuration of a filament winding apparatus 1 (sometimes simply referred to as FW apparatus 1) of the present embodiment. FIG. 1 is a side view of the first roller 11 in a contact position. FIG. 2 is a top view of FIG. 1. FIG. 3 is a side view in a state in which the first roller 11 is located at a separate position. For the sake of clarity, the configurations of the upper portion of the housing 15, the first adjustment mechanism 20, the second adjustment mechanism 30, the third roller 13, etc. are not shown in FIG. 2. The FW apparatus 1 is a device that winds the resin-impregnated fiber bundle 70 around the workpiece 60 while applying tension. The fiber bundle 70 is obtained by impregnating a thermosetting epoxy resin with a fiber bundle, for example.

[0039]The FW apparatus 1 mainly includes a guide unit 10, a control unit 50, and a rotation device 61. As shown in FIG. 2, the rotation device...

second embodiment

[0066]The second embodiment is different from the first embodiment in that the second process (combination winding) can be omitted. Only the differences from the first embodiment will be described below.

[0067]In the flowchart of FIG. 6, when the first process (helical winding) of S15 is completed, an end process is performed. The content of the end process has been described in S60 to S130 of the first embodiment.

[0068]Next, the guide unit 10 is moved to the hoop winding starting position (see position P6 in FIG. 5B). Then, a start process is performed. The content of the starting process has been described in S5 of the first embodiment. Then, a first process (hoop winding) of S50 is performed. Since the subsequent processes are the same as in the first embodiment, the description thereof will not be repeated.

[0069]In the technique of the second embodiment, the second process (combination winding) of switching between helical winding and hoop winding can be omitted. Since the asymme...

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to Japanese Patent Application No. 2024-114252 filed on Jul. 17, 2024. The disclosure of the above-identified application, including the specification, drawings, and claims, is incorporated by reference herein in its entirety.BACKGROUND1. Technical Field

[0002] The technique disclosed herein relates to filament winding apparatuses.2. Description of Related Art

[0003] Japanese Unexamined Patent Application Publication No. 2020-139581 (JP 2020-139581 A) describes a filament winding apparatus that can perform a winding process. In the winding process, a fiber bundle is wound around a workpiece by bringing the fiber bundle into close contact with the periphery of the workpiece while holding the fiber bundle under tension.SUMMARY

[0004] There is a case where a fiber bundle cannot be brought into sufficiently close contact with the surface of a workpiece and a protruding portion is formed during a series of winding processes. For example, when the winding pattern is changed between helical winding and hoop winding etc., a protruding portion may be formed due to a decrease in tension applied to a fiber bundle. In another example, when the winding pattern is changed, a protruding portion may be formed due to fiber crossovers being formed due to an asymmetrical, irregular winding method. The protruding portion causes undulation (bending) when the fiber bundle is placed on the previous layer in the subsequent step. Fiber strength may decrease in the bent portion, which may result in reduced fatigue performance.

[0005] A filament winding apparatus disclosed in the present specification includes a rotation device configured to rotate a workpiece.

[0006] The filament winding apparatus includes a guide unit that is movable in an axial direction parallel to a rotation axis of the workpiece. The guide unit is configured to guide a fiber bundle to be fed to the workpiece on the rotation device.

[0007] The guide unit includes a first roller configured to guide the fiber bundle, and a first adjustment mechanism configured to adjust a distance between the first roller and the workpiece.

[0008] The filament winding apparatus includes a control unit configured to control operation of the first adjustment mechanism.

[0009] The control unit is configured to move the first roller away from a surface of the workpiece in a predetermined first process of a series of winding processes, and is configured to bring the first roller into contact with the surface of the workpiece with the fiber bundle between the first roller and the surface of the workpiece in a predetermined second process of the series of winding processes.

[0010] With the above configuration, the first roller can be moved away from the surface of the workpiece in the predetermined first process. This can reduce various resistances that are generated by the first roller, and can thus increase the winding speed. Moreover, the fiber bundle can be pressed against the surface of the workpiece by the first roller in the second process. The fiber bundle can thus be brought into sufficiently close contact with the surface of the workpiece, so that a step at a protruding portion can be minimized. It is therefore possible to reduce a decrease in fatigue performance while maintaining the throughput of the winding process.BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Features, advantages, and technical and industrial significance of exemplary embodiments of the disclosure will be described below with reference to the accompanying drawings, in which like signs denote like elements, and wherein:

[0012] FIG. 1 is a side view of an FW apparatus 1 with a first roller 11 located at a contact position;

[0013] FIG. 2 is a top view of the FW apparatus 1 with the first roller 11 located at the contact position;

[0014] FIG. 3 is a side view of the FW apparatus 1 with the first roller 11 located at a separate position;

[0015] FIG. 4 is a side view of the FW apparatus 1 with a second roller 12 and a third roller 13 in a fixed state;

[0016] FIG. 5A is a diagram illustrating a type of winding process;

[0017] FIG. 5B is a diagram illustrating a type of winding process;

[0018] FIG. 5C is a diagram illustrating a type of winding process; and

[0019] FIG. 6 is a flowchart illustrating the operation of the FW apparatus 1.DETAILED DESCRIPTION OF EMBODIMENTS

[0020] Additional features of the filament winding apparatus disclosed herein are listed below.

[0021] In one embodiment of the present technology,

[0022] The first process may include performing helical winding and performing hoop winding.

[0023] The second process may include switching between helical winding and hoop winding.

[0024] According to the above configuration, in the first process, the processing speed of the helical winding and the hoop winding can be increased. In the second process, the fiber bundle can be pressed against the surface of the workpiece by the first roller. It is possible to minimize a step at a protruding portion that is formed when the winding method is switched.

[0025] In one embodiment of the present technology,

[0026] The guide unit may further include a second roller and a third roller disposed farther from the workpiece than the first roller and opposed to each other and passing the fiber bundle between the rollers.

[0027] The guide unit may further include a second adjustment mechanism configured to adjust a distance between the second roller and the third roller.

[0028] The guide unit may further include a cutting mechanism arranged on the feed path for the fiber bundle from the second roller and the third roller to the first roller.

[0029] The second adjustment mechanism may be able to change a state between a fixed state in which the second roller and the third roller are in contact with each other via the fiber bundle, and a non-fixed state in which the second roller and the third roller are separated from each other.

[0030] The control unit may set the second roller and the third roller to the non-fixed state during the series of winding processes.

[0031] In an end process for ending the series of winding processes, the control unit may stop rotating the workpiece, set the second roller and the third roller to the fixed state, and cut the fiber bundle by the cutting mechanism.

[0032] According to the above configuration, the fiber bundle can be cut while the fiber bundle is held in a fixed state by sandwiching the fiber bundle by the second roller and the third roller. Since the fiber bundle can be cut in a state in which tension is applied to the fiber bundle, it is possible to reliably cut.

[0033] In one embodiment of the present technology,

[0034] In the end process, the control unit may bring the first roller into contact with the surface of the workpiece with the fiber bundle therebetween before cutting the fiber bundle.

[0035] In the end process, the control unit may rotate the workpiece so as to cause the first roller to pass on the cut end of the fiber bundle with the first roller being in contact with the fiber bundle after cutting the fiber bundle.

[0036] According to the above configuration, the cut end of the fiber bundle can be pressed against the surface of the workpiece by the first roller. A step at a protruding portion that is formed at the cut end of the fiber bundle can be minimized.

[0037] In an embodiment of the present technology, the first adjustment mechanism may be configured to be capable of changing a relative position of the first roller with respect to the housing of the guide unit.First EmbodimentSchematic configuration of Filament Winding Apparatus 1

[0038] FIGS. 1 to 3 show a schematic configuration of a filament winding apparatus 1 (sometimes simply referred to as FW apparatus 1) of the present embodiment. FIG. 1 is a side view of the first roller 11 in a contact position. FIG. 2 is a top view of FIG. 1. FIG. 3 is a side view in a state in which the first roller 11 is located at a separate position. For the sake of clarity, the configurations of the upper portion of the housing 15, the first adjustment mechanism 20, the second adjustment mechanism 30, the third roller 13, etc. are not shown in FIG. 2. The FW apparatus 1 is a device that winds the resin-impregnated fiber bundle 70 around the workpiece 60 while applying tension. The fiber bundle 70 is obtained by impregnating a thermosetting epoxy resin with a fiber bundle, for example.

[0039] The FW apparatus 1 mainly includes a guide unit 10, a control unit 50, and a rotation device 61. As shown in FIG. 2, the rotation device 61 is a device that rotatably fixes the workpiece 60. The workpiece 60 is a cylindrical hollow container. The workpiece 60 has a gas barrier property and is filled with a high-pressure gas such as hydrogen. The workpiece 60 includes a cylindrical body portion 60b and a pair of dome portions 60d. The pair of dome portions 60d is connected to both ends of the body portion 60b. The workpiece 60 includes a rotation axis RA. The rotation device 61 rotates the workpiece 60 about the rotation axis RA.

[0040] The guide unit 10 is a mechanism for guiding the fiber bundle 70 supplied to the workpiece 60. The guide unit 10 is also referred to as an eye, a feed eye, or the like. The guide unit 10 is movable along an axial direction (y-axis direction) parallel to the rotation axis RA of the workpiece 60, and is movable along a front-rear axis (x-axis direction).

[0041] The guide unit 10 mainly includes a first roller 11, a second roller 12, a third roller 13, a fourth roller 14, a housing 15, a first adjustment mechanism 20, a second adjustment mechanism 30, and a cutting mechanism 40. The first roller 11 to the fourth roller 14 are rollers that guide the fiber bundle 70. The first roller 11 to the fourth roller 14 are rotatably supported by a support shaft, not shown, and are arranged parallel to each other. The first roller 11 is disposed on the distal end side of the guide unit 10. The second roller 12 and the third roller 13 are disposed farther away from the workpiece 60 than the first roller 11. The second roller 12 and the third roller 13 are disposed so as to face each other, and the fiber bundle 70 passes between the rollers. In the present embodiment, the fiber bundle 70 enters from the fourth roller 14 side, contacts the lower outer periphery of the fourth roller 14, the upper outer periphery of the second roller 12, and the lower outer periphery of the first roller 11, and is supplied to the workpiece 60.

[0042] The first adjustment mechanism 20 includes an actuator 21, a rack 22, a pinion 23, and a roller support portion 24. In the present embodiment, the actuator 21 is a cylinder. The cylinder may be a pneumatic, hydraulic, or electric cylinder. The actuator 21 moves the pinion 23 in the moving direction D1. The pinion 23 moves linearly on the rack 22. One end of the roller support portion 24 is fixed to the pinion 23. The first roller 11 is rotatably supported at the other end of the roller support portion 24.

[0043] The first adjustment mechanism 20 is a mechanism that can adjust the distance between the first roller 11 and the workpiece 60. In other words, the first adjustment mechanism 20 can change the relative position of the first roller 11 with respect to the housing 15. This will be specifically described. The first adjustment mechanism 20 can change the position of the first roller 11 between the contact position (FIG. 1) and the separate position (FIG. 3). The contact position in FIG. 1 is a position where the first roller 11 is in contact with the surface of the workpiece 60 with the fiber bundle 70 therebetween. The separate position in FIG. 3 is a position in which the first roller 11 is located away from the surface of the workpiece 60.

[0044] The second adjustment mechanism 30 is an actuator. In the present embodiment, the second adjustment mechanism 30 is a cylinder. The second adjustment mechanism 30 moves the third roller 13 in the moving direction D2. The second adjustment mechanism 30 is a mechanism that can adjust the distance between the second roller 12 and the third roller 13. That is, the second adjustment mechanism can change the second roller 12 and the third roller 13 between the non-fixed state (FIGS. 1 and 3) and the fixed state (FIG. 4). In the non-fixed state (FIGS. 1 and 3), the second roller 12 and the third roller 13 are separated from each other. The fixed state (FIG. 4) is a state in which the second roller 12 and the third roller 13 are in contact with each other with the fiber bundle 70 therebetween. In other words, the fixed state is a state in which the fiber bundle 70 is clamped and fixed by the second roller 12 and the third roller 13.

[0045] The cutting mechanism 40 is disposed on the feed path for the fiber bundle 70 between the second roller 12 and third roller 13 and the first roller 11. As shown in FIG. 2, the cutting mechanism 40 includes a cutter 41 and a rail 42. The rail 42 is disposed in a direction (y direction) perpendicular to the supply direction (x direction) of the fiber bundle 70. The cutter 41 is configured to be movable on the rail 42 by an actuator, not shown (see arrow Y1). The cutter 41 is separated from the feed path of the fiber bundle 70 in the retracted position of FIG. 2. The fiber bundle 70 can then be cut by the cutter 41 moving the rail 42 in Y1 of the arrow.

[0046] The control unit 50 is a part that controls operations of the first adjustment mechanism 20, the second adjustment mechanism 30, the cutting mechanism 40, the rotation device 61, and the like. The control unit 50 may be configured as a computer including a CPU and memories. Various mechanisms may be controlled by the CPU executing a control program stored in the memory.Content of Each Winding Process

[0047] A series of winding processes are performed by winding a continuous fiber bundle 70 around the workpiece 60. The series of winding processes includes a first process and a second process. The first process is a process of performing helical winding and hoop winding. Helical winding is a process in which the fiber bundle 70 is wound in a spiral shape in the rotation axis RA as shown in FIG. 5A. In other words, the helical winding is a winding method in which the angle with respect to the rotation axis RA is a relatively low angle, and is a winding method in which the helical winding is applied to the pair of dome portions 60d. As shown in FIG. 5C, the hoop winding is a process of winding the fiber bundle 70 around the body portion 60b. In other words, the hoop winding is a winding method in which the angle with respect to the rotation axis RA is a relatively high angle, and is a winding method in which the hoop winding is not applied to the pair of dome portions 60d. Note that the hoop winding in the present specification includes a so-called high-angle helical winding.

[0048] The second process is a process of switching between helical winding and hoop winding. In the present embodiment, in the second process, the combination winding shown in FIG. 5B is performed. Combination winding is a winding method for raising an angle with respect to the rotation axis RA from a low angle state (helical winding) to a high angle state (hoop winding). The combination winding has a threading path that passes in sequence from the position P1 to the position P6. The position P1 is the end point position of the helical winding. The position P6 is the starting position of the hoop winding. Since the combination winding is an asymmetrical, irregular winding method, a plurality of protruding portions is formed on the surface of the workpiece 60.Operation of FW Apparatus 1

[0049] The operation of the FW apparatus 1 will be described with reference to the flowchart of FIG. 6. The FW apparatus 1 performs a starting process (S5), a series of winding processes (S10 to S50), and an end process (S60 to S130).

[0050] Prior to performing S5, the distal end of the fiber bundle 70 is set on the first roller 11. The content of setting the distal end of the fiber bundle 70 will be described later in S130.

[0051] In S5, the first adjustment mechanism 20 moves the position of the first roller 11 to the contact position (FIG. 1). As a result, the distal end of the fiber bundle 70 can be pressed against the surface of the workpiece 60 by the first roller 11.

[0052] Next, the winding processes (S10 to S50) will be described. During the winding process, the second roller 12 and the third roller 13 are kept in the non-fixed state.

[0053] In S10, the first adjustment mechanism 20 moves the position of the first roller 11 to the separate position (FIG. 3). The first roller 11 is thus located away from the surface of the workpiece 60. In S15, the control unit 50 performs the first process (helical winding) (see FIG. 5A). The first process is performed with the first roller 11 located at the separate position (FIG. 3). Once helical placement is complete, the process proceed to S20.

[0054] In S20, the first adjustment mechanism 20 moves the position of the first roller 11 to the contact position (FIG. 1). As a result, the first roller 11 comes into contact with the surface of the workpiece 60 with the fiber bundle 70 therebetween. The first roller 11 may be moved while the workpiece 60 is rotated, or the first roller 11 may be moved after the rotation of the workpiece 60 is stopped.

[0055] In S30, the control unit 50 performs the second process (combination winding) (see FIG. 5B). The combination winding process is performed in a state where the position of the first roller 11 is set to the contact position (FIG. 1). When the fiber bundle 70 is wound up to the position P6 in FIG. 5B, the process proceeds to S40.

[0056] In S40, the first adjustment mechanism 20 moves the first roller 11 to the separate position (FIG. 3). In S50, the control unit 50 performs the first process (hoop winding) (see FIG. 5C). The first process is performed with the first roller 11 located at the separate position (FIG. 3). Then, when placement of all the layers is completed, the process proceeds to S60.

[0057] The end process (S60 to S130) will be described. In S60, the control unit 50 stops the workpiece 60 from rotating. In S70, the first adjustment mechanism 20 moves the position of the first roller 11 to the contact position (FIG. 1).

[0058] In S80, the second adjustment mechanism 30 moves the third roller 13 toward the second roller 12. As a result, the fiber bundle 70 can be held in the fixed state by the second roller 12 and the third roller 13 (see area A1 in FIG. 4).

[0059] In S90, the cutting mechanism 40 cuts the fiber bundle 70 by moving the cutter 41 across the fiber bundle 70 (see arrow Y1 in FIG. 2). At this time, the fiber bundle 70 on the distal end side (−x direction side) of the cutter 41 is pressed against and fixed to the workpiece 60 by the first roller 11 (see area A2 in FIG. 4). The fiber bundle 70 on the root side (+x direction side) of the cutter 41 is clamped and fixed to the second roller 12 and the third roller 13 (see area A1). Therefore, the fiber bundle 70 can be cut in a state where tension is applied to the fiber bundle 70. Since the cutter 41 can be prevented from escaping, cutting can be reliably performed.

[0060] FIG. 4 shows the state of the fiber bundle 70 after cutting. The cut end 70e and the distal end 70t are formed in the fiber bundle 70 after the cut. The cut end 70 e is located on the workpiece 60. The distal end 70t is clamped and fixed by the second roller 12 and the third roller 13.

[0061] In S100, the control unit 50 performs a process of pressure-bonding the cut end 70e to the surface of the workpiece 60. Specifically, the workpiece 60 is rotated in the rotation direction R1 from the state shown in FIG. 4. This allows the first roller 11 to pass through the upper surface of the cut end 70e while contacting the fiber bundle 70. Since the first roller 11 can pressure-bond the cut end 70e, curling of the cut end 70e can be reduced.

[0062] In S110, the first adjustment mechanism 20 moves the first roller 11 to the separate position (FIG. 3). In S120, the control unit 50 blows hot air to the cut end 70e by a hot air blower, not shown. Accordingly, the cut end 70e can be securely fixed to the front face of the workpiece 60. Note that this step may be skipped.

[0063] In S 130, a process of setting the distal end 70t to the first roller 11 is executed. Specifically, the control unit 50 rotates the second roller 12 and the third roller 13 in a state where the fiber bundle 70 is sandwiched therebetween. As a result, the distal end 70t of the fiber bundle 70 can be fed to the first roller 11. Therefore, S5 of the subsequent winding process can be executed. Since the winding processing can be continuously performed, the winding processing process can be automated. Throughput can be improved, and manufacturing cost can be reduced.Effects

[0064] The problem is described. There is a case where the fiber bundle 70 cannot be brought into sufficiently close contact with the surface of the workpiece 60 and a protruding portion is formed during a series of winding processes. For example, when the winding pattern is changed between helical winding and hoop winding etc., a protruding portion may be formed due to a decrease in tension applied to the fiber bundle 70. In another example, when the winding pattern is changed, a protruding portion may be formed due to fiber crossovers being formed due to an asymmetric, irregular winding method (combination winding). The protruding portion causes undulation (bending) when the fiber bundle is placed on the previous layer in the subsequent step. Fiber strength may decrease in the bent portion, which may result in reduced fatigue performance.

[0065] Therefore, in the technology of the present specification, the first roller 11 can be moved away from the surface of the workpiece 60 in a predetermined first process (helical winding and hoop winding). As a result, various resistances generated by the first roller 11 can be reduced, and thus the winding speed can be increased. Further, in a predetermined second process (combination winding), the fiber bundle 70 can be wound while the fiber bundle 70 is pressed against the surface of the workpiece 60 by the first roller 11. As a result, the fiber bundle 70 can be brought into sufficiently close contact with the surface of the workpiece 60, so that a step at a protruding portion can be minimized. It is possible to reduce a decrease in fatigue performance while maintaining the throughput of the winding process.Second Embodiment

[0066] The second embodiment is different from the first embodiment in that the second process (combination winding) can be omitted. Only the differences from the first embodiment will be described below.

[0067] In the flowchart of FIG. 6, when the first process (helical winding) of S15 is completed, an end process is performed. The content of the end process has been described in S60 to S130 of the first embodiment.

[0068] Next, the guide unit 10 is moved to the hoop winding starting position (see position P6 in FIG. 5B). Then, a start process is performed. The content of the starting process has been described in S5 of the first embodiment. Then, a first process (hoop winding) of S50 is performed. Since the subsequent processes are the same as in the first embodiment, the description thereof will not be repeated.

[0069] In the technique of the second embodiment, the second process (combination winding) of switching between helical winding and hoop winding can be omitted. Since the asymmetrically, irregularly wound layers can be eliminated, it is possible to reduce formation of protruding portions. The fatigue performance can be further improved.

[0070] Although the embodiments have been described in detail above, these are merely examples and do not limit the scope of the claims. The technique described in the claims includes various modifications and variations of the specific examples exemplified above. The technical elements described in the present specification or in the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing the application. In addition, the technique exemplified in the present specification or drawings can achieve a plurality of purposes at the same time, and achieving one of the purposes itself has technical usefulness.Modification

[0071] The process of winding the fiber bundle 70 with the first roller 11 located at the contact position (FIG. 1) is not limited to the second process (combination winding). The present disclosure can be applied to any process as long as it is a process in which it is necessary to reduce fiber undulation and increase the quality of fiber layers. For example, the first roller 11 may be brought into contact with the very first winding start portion (also referred to as three-circuit) of the fiber bundle 70.

[0072] The mechanism for moving the first roller 11 to the contact position is not limited to the first adjustment mechanism 20, and may be various mechanisms. For example, the guide unit 10 itself may move.

[0073] The actuators included in the first adjustment mechanism 20 and the second adjustment mechanism 30 may be various mechanisms. For example, a linear motion system, a ball screw, or the like may be used.

[0074] The cutting mechanism 40 may be a variety of mechanisms. For example, the cutter 41 may be moved in a direction (z direction) perpendicular to the surface of the fiber bundle 70.

Examples

first embodiment

Schematic configuration of Filament Winding Apparatus 1

[0038]FIGS. 1 to 3 show a schematic configuration of a filament winding apparatus 1 (sometimes simply referred to as FW apparatus 1) of the present embodiment. FIG. 1 is a side view of the first roller 11 in a contact position. FIG. 2 is a top view of FIG. 1. FIG. 3 is a side view in a state in which the first roller 11 is located at a separate position. For the sake of clarity, the configurations of the upper portion of the housing 15, the first adjustment mechanism 20, the second adjustment mechanism 30, the third roller 13, etc. are not shown in FIG. 2. The FW apparatus 1 is a device that winds the resin-impregnated fiber bundle 70 around the workpiece 60 while applying tension. The fiber bundle 70 is obtained by impregnating a thermosetting epoxy resin with a fiber bundle, for example.

[0039]The FW apparatus 1 mainly includes a guide unit 10, a control unit 50, and a rotation device 61. As shown in FIG. 2, the rotation device...

second embodiment

[0066]The second embodiment is different from the first embodiment in that the second process (combination winding) can be omitted. Only the differences from the first embodiment will be described below.

[0067]In the flowchart of FIG. 6, when the first process (helical winding) of S15 is completed, an end process is performed. The content of the end process has been described in S60 to S130 of the first embodiment.

[0068]Next, the guide unit 10 is moved to the hoop winding starting position (see position P6 in FIG. 5B). Then, a start process is performed. The content of the starting process has been described in S5 of the first embodiment. Then, a first process (hoop winding) of S50 is performed. Since the subsequent processes are the same as in the first embodiment, the description thereof will not be repeated.

[0069]In the technique of the second embodiment, the second process (combination winding) of switching between helical winding and hoop winding can be omitted. Since the asymme...

Claims

1. A filament winding apparatus comprising:a rotation device configured to rotate a workpiece;a guide unit that is movable in an axial direction parallel to a rotation axis of the workpiece, the guide unit being configured to guide a fiber bundle to be fed to the workpiece on the rotation device, and the guide unit includinga first roller configured to guide the fiber bundle, anda first adjustment mechanism configured to adjust a distance between the first roller and the workpiece; anda control unit configured to control operation of the first adjustment mechanism,wherein the control unit is configured to move the first roller away from a surface of the workpiece in a predetermined first process of a series of winding processes, and is configured to bring the first roller into contact with the surface of the workpiece with the fiber bundle between the first roller and the surface of the workpiece in a predetermined second process of the series of winding processes.

2. The filament winding apparatus according to claim 1, wherein:the first process includes performing helical winding and performing hoop winding; andthe second process includes switching between the helical winding and the hoop winding.

3. The filament winding apparatus according to claim 2, wherein:the guide unit further includesa second roller and a third roller that are located farther away from the workpiece than the first roller and that are disposed so as to face each other, the fiber bundle being passed between the second roller and the third roller,a second adjustment mechanism configured to adjust a distance between the second roller and the third roller, anda cutting mechanism located on a feed path for the fiber bundle from the second roller and the third roller to the first roller;the second adjustment mechanism is configured to change a state between a fixed state and a non-fixed state, the fixed state being a state in which the second roller and the third roller are in contact with each other with the fiber bundle between the second roller and the third roller, and the non-fixed state being a state in which the second roller and the third roller are separated from each other; andthe control unit is configured toset the second roller and the third roller to the non-fixed state during the series of winding processes, andstop rotating the workpiece, set the second roller and the third roller to the fixed state, and cut the fiber bundle by the cutting mechanism in an end process that is performed to end the series of winding processes.

4. The filament winding apparatus according to claim 3, wherein the control unit is configured to, in the end process,before cutting the fiber bundle, bring the first roller into contact with the surface of the workpiece with the fiber bundle between the first roller and the surface of the workpiece, andafter cutting the fiber bundle, rotate the workpiece so as to cause the first roller to pass on a cut end of the fiber bundle with the first roller being in contact with the fiber bundle.

5. The filament winding apparatus according to claim 1, wherein the first adjustment mechanism is configured to change a relative position of the first roller with respect to a housing of the guide unit.

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