JP2020037961A

JP2020037961A - Tank manufacturing method

Info

Publication number: JP2020037961A
Application number: JP2018164356A
Authority: JP
Inventors: 建一高洲; Kenichi Takasu
Original assignee: Toyota Motor Corp
Current assignee: Toyota Motor Corp
Priority date: 2018-09-03
Filing date: 2018-09-03
Publication date: 2020-03-12

Abstract

To provide a tank manufacturing method by which reduction in the strength of a tank due to an operation for winding fiber-reinforcing resin can be suppressed.SOLUTION: A tank manufacturing method comprises winding a belt-like fiber-reinforcing resin 30 around a rotating liner 11 while applying tensile force, and includes a hoop winding process of repeating hoop winding of the fiber-reinforcing resin around at least a body part while reciprocating a fiber-reinforcing resin winding position in the shaft direction of a cylindrical body part 17 of the liner. In the hoop winding process, when performing a turn-back action for reversing the movement direction of the fiber-reinforcing resin winding position, fiber-reinforcing resin is wound around the liner by tensile force lower than the tensile force of the fiber-reinforcing resin before/after the turn-back action.SELECTED DRAWING: Figure 4

Description

本発明は、タンクの製造方法に関する。 The present invention relates to a method for manufacturing a tank.

従来、タンクとして、ガス等の高圧流体が充填されるライナを繊維強化樹脂で外側から補強した高圧タンクが知られている（例えば、特許文献１参照）。特許文献１に記載の高圧タンクの製造時には、いわゆるフィラメントワインディング工法（以下、ＦＷ工法と称する）によって、帯状の繊維強化樹脂に適度な張力をかけながら、ライナの周回りに繊維強化樹脂が巻き付けられる。ＦＷ工法では、ライナが回転して繊維強化樹脂を巻き取りながら、ライナの筒状の胴体部に周回りに強化繊維を巻き付けるフープ巻き工程が行われる。フープ巻き工程では、ライナの軸方向に繊維強化樹脂の巻き付け位置が往復移動されることで、胴体部の周りに幾重にも繊維強化樹脂が巻き付けられる。 2. Description of the Related Art Conventionally, as a tank, a high-pressure tank in which a liner filled with a high-pressure fluid such as a gas is reinforced from outside with a fiber-reinforced resin is known (for example, see Patent Document 1). At the time of manufacturing the high-pressure tank described in Patent Literature 1, the so-called filament winding method (hereinafter, referred to as FW method) is used to wind the fiber-reinforced resin around the liner while applying an appropriate tension to the belt-shaped fiber-reinforced resin. . In the FW method, a hoop winding step of winding a reinforcing fiber around a cylindrical body portion of a liner while rotating the liner to wind the fiber reinforced resin is performed. In the hoop winding process, the winding position of the fiber reinforced resin is reciprocated in the axial direction of the liner, so that the fiber reinforced resin is wound around the body in multiple layers.

特開２０１７−１８５７４２号公報JP 2017-185742 A

ところで、フープ巻き工程において繊維強化樹脂の折り返し動作を行う際に、帯状の繊維強化樹脂が捩れた状態でライナの胴体部に巻き付いて、繊維強化樹脂が本来の強度を発揮することができずにタンク強度が低下するという問題があった。 By the way, when performing the folding operation of the fiber-reinforced resin in the hoop winding process, the band-shaped fiber-reinforced resin is wound around the body of the liner in a twisted state, and the fiber-reinforced resin cannot exhibit its original strength. There was a problem that the tank strength was reduced.

本発明では、繊維強化樹脂の巻き付け動作に起因したタンク強度の低下を抑えることができるタンクの製造方法を提供することを目的とする。 An object of the present invention is to provide a method for manufacturing a tank that can suppress a decrease in tank strength due to a winding operation of a fiber-reinforced resin.

上記課題を解決するために、本発明に係るタンクの製造方法は、回転しているライナに対して張力を付与しながら帯状の繊維強化樹脂を巻き付けるタンクの製造方法であって、前記繊維強化樹脂の巻き付け位置を前記ライナの筒状の胴体部の軸方向に往復させながら、少なくとも前記胴体部に対して前記繊維強化樹脂のフープ巻きを繰り返すフープ巻き工程を有し、前記フープ巻き工程では、前記繊維強化樹脂の巻き付け位置の移動方向を逆向きにする折り返し動作を行う際に、前記折り返し動作の前後の前記繊維強化樹脂の張力よりも低い張力で前記繊維強化樹脂を前記ライナに巻き付けることを特徴とする。 In order to solve the above problems, a method for manufacturing a tank according to the present invention is a method for manufacturing a tank in which a belt-shaped fiber reinforced resin is wound while applying tension to a rotating liner, wherein the fiber reinforced resin is provided. A hoop winding step of repeating a hoop winding of the fiber-reinforced resin on at least the body while reciprocating the winding position in the axial direction of the cylindrical body of the liner, wherein in the hoop winding step, When performing a folding operation in which the movement direction of the winding position of the fiber reinforced resin is reversed, the fiber reinforced resin is wound around the liner with a tension lower than the tension of the fiber reinforced resin before and after the folding operation. And

本発明によれば、ライナの胴体部に対するフープ巻き工程の折り返し動作を行う際に、折り返し動作の前後の張力よりも低い張力で帯状の繊維強化樹脂がライナに巻き付けられる。このため、折り返し動作による繊維強化樹脂の捩れが少なくなって、繊維強化樹脂の折り返し位置におけるタンク強度の低下を抑えることができる。 ADVANTAGE OF THE INVENTION According to this invention, when performing the folding operation | movement of the hoop winding process with respect to the trunk | drum part of a liner, the belt-shaped fiber reinforced resin is wound around a liner with tension lower than the tension before and after the folding operation. For this reason, the twisting of the fiber reinforced resin due to the folding operation is reduced, and a decrease in the tank strength at the folding position of the fiber reinforced resin can be suppressed.

本実施形態に係る高圧タンクの断面模式図である。It is a cross section of a high-pressure tank concerning this embodiment. 本実施形態に係るフープ巻き工程の概略説明図である。It is a schematic explanatory view of a hoop winding process concerning this embodiment. 比較例に係るフープ巻き工程の詳細説明図である。It is a detailed explanatory view of a hoop winding process concerning a comparative example. 本実施形態に係るフープ巻き工程の詳細説明図である。It is a detailed explanatory view of the hoop winding process concerning this embodiment. 繊維強化樹脂の張力と樹脂幅の関係を示すグラフである。It is a graph which shows the relationship of the tension of a fiber reinforced resin and resin width. 本実施形態に係るタンクの製造方法の一例を示すフローチャートである。It is a flowchart which shows an example of the manufacturing method of the tank which concerns on this embodiment.

以下、本実施形態について説明する。図１は、本実施形態に係る高圧タンク１０の断面模式図であり、高圧タンク１０を長手方向の中心軸ＣＸを含む面で切断した側方断面構造を示している。図２は本実施形態に係るフープ巻き工程の概略説明図である。なお、以下の説明では、タンクとして車載用の燃料電池システムで燃料電池に水素等の燃料ガスを貯蔵する高圧タンクを例示して説明するが、タンクは燃料電池システム以外の任意の用途で使用されてもよい。 Hereinafter, the present embodiment will be described. FIG. 1 is a schematic cross-sectional view of a high-pressure tank 10 according to the present embodiment, and shows a side cross-sectional structure of the high-pressure tank 10 cut along a plane including a central axis CX in a longitudinal direction. FIG. 2 is a schematic explanatory view of the hoop winding step according to the present embodiment. In the following description, a high-pressure tank that stores a fuel gas such as hydrogen in a fuel cell in a vehicle-mounted fuel cell system will be described as an example of a tank, but the tank is used for any purpose other than the fuel cell system. You may.

図１に示すように、高圧タンク１０は、タンクの基材となるライナ１１の外面を繊維強化樹脂層１２で被覆したタンク本体１３を有している。タンク本体１３は、円筒部１４の両端から一対のドーム部１５、１６を半球状に膨出させた外面形状を有している。各ドーム部１５、１６の頂点部分は開口しており、各ドーム部１５、１６のそれぞれの開口に口金２１、２５が取り付けられている。一方の口金２１にはバルブ２８が取り付けられており、バルブ２８によってタンク本体１３内のガスの放出および流入が行われる。他方の口金２５でドーム部１６の開口が遮蔽されており、口金２５によってタンク本体１３内が気密に封止されている。 As shown in FIG. 1, the high-pressure tank 10 has a tank body 13 in which a liner 11 serving as a base material of the tank is covered with a fiber-reinforced resin layer 12. The tank body 13 has an outer surface shape in which a pair of dome portions 15 and 16 are bulged in a hemispherical shape from both ends of the cylindrical portion 14. The apexes of the domes 15 and 16 are open, and bases 21 and 25 are attached to the respective openings of the domes 15 and 16. A valve 28 is attached to one of the bases 21, and the gas in the tank body 13 is discharged and flowed in by the valve 28. The other base 25 shields the opening of the dome portion 16, and the base 25 hermetically seals the inside of the tank body 13.

ライナ１１は、燃料ガスに対するガスバリア性を有する樹脂によって形成されている。ライナ１１の本体となる筒状の胴体部１７の両端部には、ライナ径を縮径させるように軸方向外側に膨出した湾曲部１８、１９が連なっており、湾曲部１８、１９の中央には内窄みの開口が形成されている。ライナ１１の樹脂材料としては、例えば、ポリアミド、エチレンビニルアルコール共重合体、ポリエチレン等の樹脂を用いることができる。ライナ１１には、燃料ガスとして水素ガスの他に、例えば、ＣＮＧ（圧縮天然ガス）等の各種圧縮ガス、ＬＮＧ（液化天然ガス）、ＬＰＧ（液化石油ガス）等の各種液化ガス、その他の各種加圧物質が充填されてもよい。なお、ライナ１１は、樹脂材料に代えてアルミニウム合金等の金属材料によって形成されていてもよい。 The liner 11 is formed of a resin having a gas barrier property against fuel gas. At both ends of a cylindrical body portion 17 serving as a main body of the liner 11, curved portions 18 and 19 bulging outward in the axial direction so as to reduce the liner diameter are continuous, and the center of the curved portions 18 and 19 is formed. Is formed with an opening for stenosis. As the resin material of the liner 11, for example, a resin such as polyamide, ethylene vinyl alcohol copolymer, or polyethylene can be used. In addition to hydrogen gas as a fuel gas, the liner 11 includes, for example, various compressed gases such as CNG (compressed natural gas), various liquefied gases such as LNG (liquefied natural gas), LPG (liquefied petroleum gas), and other various types. A pressurized substance may be charged. The liner 11 may be formed of a metal material such as an aluminum alloy instead of the resin material.

繊維強化樹脂層１２は、一方向に引き揃えられた強化繊維に、未硬化樹脂（未硬化の熱硬化性樹脂）が含浸された繊維強化樹脂３０（図２参照）をライナ１１の外面に幾重にも巻き付けて、加熱炉で未硬化樹脂を硬化させることで形成される。繊維強化樹脂層１２は、繊維強化樹脂３０をフープ巻きしたフープ層Ｌ１と繊維強化樹脂３０をヘリカル巻きしたヘリカル層Ｌ２とで形成されている。フープ巻きはライナ１１の胴体部１７に対して繊維強化樹脂３０を部分的にフープ状に巻き付ける巻き付け態様であり、ヘリカル巻きはライナ１１に対して中心軸ＣＸに対して１０°から６０°の角度で繊維強化樹脂３０をヘリカル状に巻き付ける巻き付け態様である。フープ層Ｌ１によってタンク強度が高められ、ヘリカル層Ｌ２によってタンク外面が形作られている。 The fiber reinforced resin layer 12 is formed by layering a fiber reinforced resin 30 (see FIG. 2) in which uncured resin (uncured thermosetting resin) is impregnated with reinforcing fibers aligned in one direction on the outer surface of the liner 11. And is formed by curing the uncured resin in a heating furnace. The fiber reinforced resin layer 12 is formed by a hoop layer L1 in which the fiber reinforced resin 30 is hoop wound and a helical layer L2 in which the fiber reinforced resin 30 is helically wound. The hoop winding is a winding mode in which the fiber reinforced resin 30 is partially wound in a hoop shape around the body portion 17 of the liner 11, and the helical winding is at an angle of 10 ° to 60 ° with respect to the central axis CX with respect to the liner 11. Is a winding mode in which the fiber reinforced resin 30 is wound helically. The tank strength is increased by the hoop layer L1, and the outer surface of the tank is formed by the helical layer L2.

なお、本実施形態では、ライナ１１に対してフープ巻きによってフープ層Ｌ１を形成した後に、ヘリカル巻きによってヘリカル層Ｌ２を形成する構成にしたが、少なくともフープ巻きを含む巻き付け態様で繊維強化樹脂がライナ１１の外面に巻き付けられて繊維強化樹脂層１２が形成されていればよい。また、強化繊維としては炭素繊維、ガラス繊維、アラミド繊維等を採用することができる。本実施形態では、強化繊維に含浸される樹脂に熱硬化性樹脂を用いるが、例えば、この樹脂に、ナイロンなどの熱可塑性樹脂を用いてもよい。この場合には、熱可塑性樹脂が軟化した状態で、繊維強化樹脂を巻き付けた後、これを放冷し、熱可塑性樹脂を硬化させればよい。繊維強化樹脂層１２によってライナ１１が外側から補強されることで高圧タンク１０の強度向上と軽量化が実現されている。 In the present embodiment, the hoop layer L1 is formed by hoop winding on the liner 11, and then the helical layer L2 is formed by helical winding. However, the fiber reinforced resin is wound at least in a winding mode including hoop winding. It is sufficient that the fiber reinforced resin layer 12 is formed by being wound around the outer surface of the fiber 11. In addition, carbon fibers, glass fibers, aramid fibers, and the like can be used as the reinforcing fibers. In the present embodiment, a thermosetting resin is used as the resin impregnated in the reinforcing fibers. For example, a thermoplastic resin such as nylon may be used as the resin. In this case, after the fiber reinforced resin is wound in a state where the thermoplastic resin is softened, the fiber reinforced resin may be allowed to cool to cure the thermoplastic resin. The liner 11 is reinforced from the outside by the fiber reinforced resin layer 12, thereby improving the strength and reducing the weight of the high-pressure tank 10.

一方の口金２１は、アルミニウムまたはその合金等の金属によって形成されている。口金２１の本体となる筒状部２２の外周にはフランジ部２３が設けられている。口金２１は、一方のドーム部１５の内側にフランジ部２３を位置付けるようにして、筒状部２２の一端をドーム部１５から外部に突出させている。筒状部２２にはバルブ２８から延びるノズル２９が差し込まれており、このノズル２９がタンク内の貯蔵空間２０から燃料ガスを排出する排出口および貯蔵空間２０に燃料ガスを充填する充填口になっている。なお、ノズル２９が排出口および充填口を兼用する構成に限らず、バルブ２８には燃料ガスの排出流路と充填流路とが個別に設けられていてもよい。 One base 21 is formed of a metal such as aluminum or an alloy thereof. A flange portion 23 is provided on the outer periphery of the cylindrical portion 22 which is the main body of the base 21. The base 21 has one end of the cylindrical portion 22 protruding outside from the dome portion 15 such that the flange portion 23 is positioned inside the one dome portion 15. A nozzle 29 extending from a valve 28 is inserted into the cylindrical portion 22. The nozzle 29 serves as an outlet for discharging fuel gas from the storage space 20 in the tank and a filling port for filling the storage space 20 with fuel gas. ing. In addition, the nozzle 29 is not limited to the configuration that also serves as the discharge port and the filling port, and the valve 28 may be separately provided with a fuel gas discharge flow path and a fuel gas flow path.

他方の口金２５は、一方の口金２１と同様に、アルミニウムまたはその合金等の金属によって形成されている。口金２５の本体となる筒状部２６の外周にはフランジ部２７が設けられている。口金２５は、他方のドーム部１６の内側にフランジ部２７を位置付けるようにして、筒状部２６の一端をドーム部１６から外部に突出させている。他方の口金２５の筒状部２６の内側が途中で遮蔽されており、口金２５によって貯蔵空間２０が密閉されている。このようにして、高圧タンク１０には、タンク本体１３、一対の口金２１、２５によって形成された貯蔵空間２０に高圧状態の燃料ガスが適宜取り出し可能な状態で貯蔵されている。 The other base 25 is formed of a metal such as aluminum or an alloy thereof, similarly to the one base 21. A flange portion 27 is provided on an outer periphery of a cylindrical portion 26 which is a main body of the base 25. The base 25 has one end of the cylindrical portion 26 protruding outside from the dome portion 16 such that the flange portion 27 is positioned inside the other dome portion 16. The inside of the cylindrical portion 26 of the other base 25 is shielded on the way, and the storage space 20 is sealed by the base 25. In this manner, in the high-pressure tank 10, the fuel gas in a high-pressure state is stored in a storage space 20 formed by the tank body 13 and the pair of bases 21 and 25 so that the fuel gas can be appropriately taken out.

図２に示すように、高圧タンク１０の製造時には、回転しているライナ１１の胴体部１７に対して、帯状の繊維強化樹脂３０の巻き付け位置を軸方向ＣＸに往復させながら、胴体部１７に繊維強化樹脂３０のフープ巻きを繰り返すフープ巻き工程が実施される。フープ巻き工程では、繊維強化樹脂３０に対して張力を付与しながら胴体部１７の外面に繊維強化樹脂３０が平らに巻き付けられ、胴体部１７と湾曲部１８、１９の境界で繊維強化樹脂３０の巻き付け位置が折り返されている。繊維強化樹脂３０の巻き付け位置の移動方向が変わらない通常の巻き付け動作と、巻き付け位置の移動方向が逆向きの折り返し動作との繰り返しによって胴体部１７に繊維強化樹脂３０が積層される。 As shown in FIG. 2, at the time of manufacturing the high-pressure tank 10, the winding position of the band-shaped fiber reinforced resin 30 is reciprocated in the axial direction CX with respect to the body 17 of the rotating liner 11, A hoop winding step of repeating the hoop winding of the fiber reinforced resin 30 is performed. In the hoop winding step, the fiber reinforced resin 30 is wound flat around the outer surface of the body portion 17 while applying tension to the fiber reinforced resin 30, and the fiber reinforced resin 30 is wound at the boundary between the body portion 17 and the curved portions 18, 19. The winding position is folded back. The fiber reinforced resin 30 is laminated on the body 17 by repeating a normal winding operation in which the moving direction of the winding position of the fiber reinforced resin 30 does not change and a folding operation in which the moving direction of the winding position is reversed.

ところで、フープ巻きの巻き付け方向Ｄ１は中心軸ＣＸに対して必ずしも直交しているわけではなく、中心軸ＣＸに垂直な方向Ｄ２に対して僅かに傾いている。巻き付け位置の移動方向が変わらない通常の巻き付け動作では、繊維強化樹脂３０の巻き付け位置の軸方向の移動速度も一定である。このため、繊維強化樹脂３０の巻き付け方向Ｄ１の傾きが変わることなく、胴体部１７に繊維強化樹脂３０のフープ巻きが繰り返されて、繊維強化樹脂３０の幅方向の張力バランスが大きく崩されることがない。繊維強化樹脂層１２に対して比較的高い張力が付与されていても、繊維強化樹脂３０に捩れを抑えて、ライナ１１の胴体部１７の外面に倣って繊維強化樹脂３０を平らに巻き付けることができる。 By the way, the winding direction D1 of the hoop winding is not always perpendicular to the central axis CX, but slightly inclined to a direction D2 perpendicular to the central axis CX. In a normal winding operation in which the moving direction of the winding position does not change, the axial moving speed of the winding position of the fiber reinforced resin 30 is also constant. For this reason, the hoop winding of the fiber reinforced resin 30 around the body portion 17 is repeated without changing the inclination of the winding direction D1 of the fiber reinforced resin 30, and the tension balance in the width direction of the fiber reinforced resin 30 may be greatly disrupted. Absent. Even if a relatively high tension is applied to the fiber reinforced resin layer 12, the fiber reinforced resin 30 can be prevented from twisting, and the fiber reinforced resin 30 can be wound flat along the outer surface of the body 17 of the liner 11. it can.

一方で、巻き付け位置の移動方向が逆向きになる折り返し動作を行う際には、繊維強化樹脂３０の巻き付け方向Ｄ１が途中で逆転することで繊維強化樹脂３０の幅方向の張力バランスが崩れ易い。折り返し動作では、繊維強化樹脂３０の巻き付け位置の軸方向の移動速度が変化する。胴体部１７の端部への繊維強化樹脂３０の巻き付け位置の移動中は移動速度が徐々に低下し、胴体部１７の端部で巻き付け位置の移動方向が反転した後に、通常の巻き取り動作の移動速度まで、移動速度が徐々に上昇される。このため、折り返し動作の開始直後から繊維強化樹脂３０の巻き付け方向Ｄ１の傾きが変化し始めて、折り返し動作の完了後に繊維強化樹脂３０の巻き付け方向Ｄ１の傾きが完全に逆転する。 On the other hand, when performing a folding operation in which the direction of movement of the winding position is reversed, the winding direction D1 of the fiber reinforced resin 30 is reversed halfway, so that the tension balance in the width direction of the fiber reinforced resin 30 tends to be lost. In the folding operation, the axial moving speed of the winding position of the fiber reinforced resin 30 changes. During the movement of the winding position of the fiber reinforced resin 30 to the end of the body 17, the moving speed gradually decreases, and after the movement direction of the winding position is reversed at the end of the body 17, a normal winding operation is performed. The moving speed is gradually increased to the moving speed. Therefore, the inclination of the winding direction D1 of the fiber reinforced resin 30 starts to change immediately after the start of the folding operation, and the inclination of the winding direction D1 of the fiber reinforced resin 30 is completely reversed after the completion of the folding operation.

このように、折り返し動作は、繊維強化樹脂３０の巻き付け位置の移動速度が低下してから移動方向の逆転後に元の移動速度に上昇するまでの動作であり、折り返し動作の前後で巻き付け方向Ｄ１の傾きが逆転する所定期間を含む動作である。折り返し動作で繊維強化樹脂３０に比較的高い張力が付与されていると、巻き付け方向Ｄ１の変化に応じて繊維強化樹脂３０の幅方向の張力バランスが急激に崩れて、ライナ１１の胴体部１７の外面に繊維強化樹脂３０が捩れた状態で巻き付けられる。この高圧タンクに破裂試験が実施されると、繊維強化樹脂３０に捩れが生じた胴体部１７の端部付近でタンクが破壊するという傾向がある。 As described above, the folding operation is an operation from the time when the moving speed of the winding position of the fiber reinforced resin 30 is reduced to the time when the moving direction is reversed and then increased to the original moving speed. This is an operation including a predetermined period in which the inclination is reversed. If a relatively high tension is applied to the fiber reinforced resin 30 by the folding operation, the tension balance in the width direction of the fiber reinforced resin 30 suddenly collapses according to the change in the winding direction D1, and the body portion 17 of the liner 11 The fiber reinforced resin 30 is wound around the outer surface in a twisted state. When a burst test is performed on this high-pressure tank, the tank tends to break near the end of the body portion 17 where the fiber-reinforced resin 30 is twisted.

そこで、本実施形態の高圧タンク１０の製造方法では、フープ巻き工程で折り返し動作を実施する際に、折り返し動作の前後の張力よりも低い張力でライナ１１の胴体部１７に繊維強化樹脂３０を巻き付けている。繊維強化樹脂３０の折り返し動作を行う際に、繊維強化樹脂３０の巻き付け方向Ｄ１の張力を低くすることで、繊維強化樹脂３０の幅方向の張力バランスの変化を緩やかにしている。繊維強化樹脂３０の折り返し動作が行われた場合でも、繊維強化樹脂３０の幅方向の張力バランスが崩れ難くなって繊維強化樹脂３０の捩れが緩和される。よって、繊維強化樹脂３０の折り返し位置である胴体部１７の端部付近でのタンク強度の低下を抑えることが可能になっている。 Therefore, in the manufacturing method of the high-pressure tank 10 of the present embodiment, when performing the folding operation in the hoop winding step, the fiber reinforced resin 30 is wound around the body portion 17 of the liner 11 with a tension lower than the tension before and after the folding operation. ing. When the folding operation of the fiber reinforced resin 30 is performed, the change in the tension balance in the width direction of the fiber reinforced resin 30 is moderated by reducing the tension in the winding direction D1 of the fiber reinforced resin 30. Even when the folding operation of the fiber reinforced resin 30 is performed, the tension balance in the width direction of the fiber reinforced resin 30 is less likely to collapse, and the twist of the fiber reinforced resin 30 is reduced. Therefore, it is possible to suppress a decrease in tank strength near the end of the body portion 17 where the fiber reinforced resin 30 is folded.

以下、本実施の形態のフープ巻き工程について詳細に説明する。図３は比較例に係るフープ巻き構成の詳細説明図であり、（ａ）は筒状部の端部の拡大図、（ｂ）は繊維強化樹脂の張力波形、（ｃ）は折り返し位置での樹脂形状をそれぞれ示している。図４は本実施形態に係るフープ巻き工程の詳細説明図であり、（ａ）は筒状部の端部の拡大図、（ｂ）は繊維強化樹脂の張力波形、（ｃ）は折り返し位置での樹脂形状をそれぞれ示している。 Hereinafter, the hoop winding step of the present embodiment will be described in detail. 3A and 3B are detailed explanatory views of a hoop winding configuration according to a comparative example, in which FIG. 3A is an enlarged view of an end portion of a tubular portion, FIG. 3B is a tension waveform of a fiber-reinforced resin, and FIG. Resin shapes are shown. 4A and 4B are detailed explanatory views of the hoop winding process according to the present embodiment, in which FIG. 4A is an enlarged view of the end of the cylindrical portion, FIG. 4B is a tension waveform of the fiber-reinforced resin, and FIG. Respectively are shown.

図３（ａ）に示すように、比較例に係るフープ巻き工程では、製造装置（不図示）の繰り出し部４１から繰り出された帯状の繊維強化樹脂３０がライナ４２の筒状の胴体部４３に巻き取られている。製造装置の繰り出し部４１の上流側で張力が調整されており、繰り出し部４１が動かされることで繊維強化樹脂３０の胴体部４３に対しての巻き付け位置が往復移動されている。これにより、胴体部４３の一端部側から他端部側に向かって巻き付け位置が移動しながら、フープ巻きが繰り返されて繊維強化樹脂３０の通常の巻き付け動作が実施され、胴体部４３の他端部にて巻き付け位置が逆方向に移動しながら、フープ巻きが繰り返されて繊維強化樹脂３０の折り返し動作が実施される。 As shown in FIG. 3A, in the hoop winding process according to the comparative example, the band-shaped fiber reinforced resin 30 fed from the feeding unit 41 of the manufacturing apparatus (not shown) is attached to the tubular body 43 of the liner 42. It has been wound up. The tension is adjusted on the upstream side of the feeding section 41 of the manufacturing apparatus, and the winding position of the fiber reinforced resin 30 around the body section 43 is reciprocated by moving the feeding section 41. Thereby, the hoop winding is repeated while the winding position moves from one end side to the other end side of the body portion 43, and the normal winding operation of the fiber reinforced resin 30 is performed. The hoop winding is repeated while the winding position moves in the opposite direction at the portion, and the folding operation of the fiber reinforced resin 30 is performed.

図３（ｂ）に示すように、比較例に係るフープ巻き工程は、繊維強化樹脂３０の巻き付け時の張力が略一定に調整されており、通常の巻き付け動作と折り返し動作で張力が変わらない。通常の巻き付け動作では、胴体部４３の一端部側から他端部側に向かって一定速度で繊維強化樹脂３０の巻き付け位置が移動しているため、繊維強化樹脂３０の巻き付け方向Ｄ１の傾きが一定である。繊維強化樹脂３０の巻き付け方向Ｄ１が変わらずに胴体部４３に巻き付けられるため、繊維強化樹脂３０の幅方向の張力バランスが大きく変わることがない。 As shown in FIG. 3B, in the hoop winding step according to the comparative example, the tension at the time of winding the fiber reinforced resin 30 is adjusted to be substantially constant, and the tension does not change between the normal winding operation and the folding operation. In the normal winding operation, the winding position of the fiber reinforced resin 30 moves at a constant speed from one end side to the other end side of the body 43, so that the inclination of the fiber reinforced resin 30 in the winding direction D1 is constant. It is. Since the winding direction D1 of the fiber reinforced resin 30 is wound around the body 43 without changing, the tension balance in the width direction of the fiber reinforced resin 30 does not change significantly.

繊維強化樹脂３０の折り返し動作では、胴体部４３の他端部の手前で繊維強化樹脂３０の巻き付け位置の移動速度が徐々に低下して、繊維強化樹脂３０の巻き付け方向Ｄ１の傾きが変化し始める。胴体部４３の他端部にて繊維強化樹脂３０の巻き付け位置の移動方向が切り替えられた後に、巻き付け位置の移動速度が元の移動速度まで徐々に上昇して、繊維強化樹脂３０の巻き付け方向Ｄ１の傾きが完全に逆転する。このとき、繊維強化樹脂３０の巻き付け方向Ｄ１には、通常の巻き付け動作と同様な張力が付与されているため、折り返し動作の前後において繊維強化樹脂３０の幅方向の張力バランスが激しく変化する。よって、図３（ｃ）に示すように、繊維強化樹脂３０の幅方向の張力バランスが崩されて繊維強化樹脂３０に捩れが生じる。そのため、胴体部４３の端部外面に繊維強化樹脂３０を平らに巻き付けることができず、捩れた繊維強化樹脂３０が起点になって胴体部４３の端部付近でタンク強度が低下する。 In the folding operation of the fiber reinforced resin 30, the moving speed of the winding position of the fiber reinforced resin 30 gradually decreases just before the other end of the body 43, and the inclination of the winding direction D1 of the fiber reinforced resin 30 starts to change. . After the moving direction of the winding position of the fiber reinforced resin 30 is switched at the other end of the body portion 43, the moving speed of the winding position gradually increases to the original moving speed, and the winding direction D1 of the fiber reinforced resin 30 is changed. Is completely reversed. At this time, in the winding direction D1 of the fiber reinforced resin 30, a tension similar to that in the normal winding operation is applied, and thus the tension balance in the width direction of the fiber reinforced resin 30 changes sharply before and after the folding operation. Therefore, as shown in FIG. 3C, the tension balance in the width direction of the fiber reinforced resin 30 is broken, and the fiber reinforced resin 30 is twisted. Therefore, the fiber reinforced resin 30 cannot be wound flat around the outer surface of the end of the body 43, and the strength of the tank decreases near the end of the body 43, starting from the twisted fiber reinforced resin 30.

これに対し、図４（ａ）に示すように、本実施の形態に係るフープ巻き工程でも、比較例と同様に製造装置（不図示）の繰り出し部３１から繰り出された帯状の繊維強化樹脂３０がライナ１１の胴体部１７に巻き取られている。製造装置の繰り出し部３１の上流側には、通常の巻き取り動作と折り返し動作で張力を可変する調整機構３２が設けられている。調整機構３２は、繊維強化樹脂３０の搬送路を形成するダンサーローラや各種ガイドローラで構成され、ダンサーローラの移動によって繊維強化樹脂３０の張力を調整して、繊維強化樹脂３０を繰り出し部３１に送り出している。 On the other hand, as shown in FIG. 4A, in the hoop winding step according to the present embodiment, similarly to the comparative example, the strip-shaped fiber reinforced resin 30 fed from the feeding section 31 of the manufacturing apparatus (not shown). Is wound around the body 17 of the liner 11. On the upstream side of the feeding section 31 of the manufacturing apparatus, there is provided an adjusting mechanism 32 that varies the tension by a normal winding operation and a folding operation. The adjusting mechanism 32 is composed of dancer rollers and various guide rollers that form a conveyance path for the fiber-reinforced resin 30. The adjustment mechanism 32 adjusts the tension of the fiber-reinforced resin 30 by moving the dancer roller, and feeds the fiber-reinforced resin 30 to the feeding unit 31. Sending out.

通常の巻き付け動作によって胴体部１７の一端部側から他端部側に向かって一定速度で繊維強化樹脂３０の巻き付け位置が移動している間には、調整機構３２によって一定の張力で繊維強化樹脂３０が胴体部１７に巻き付けられる。折り返し動作によって胴体部１７の端部付近で繊維強化樹脂３０の巻き付け位置の移動方向が切り替えられている間には、調整機構３２によって通常の巻き付け動作よりも低い張力で繊維強化樹脂３０が胴体部１７に巻き付けられる。折り返し動作が完了すると通常の巻き付け動作が再開され、調整機構３２によって一定の張力で再び繊維強化樹脂３０が胴体部１７に巻き付けられる。 While the winding position of the fiber reinforced resin 30 is moving at a constant speed from one end side of the body portion 17 to the other end side by a normal winding operation, the fiber reinforced resin is adjusted with a constant tension by the adjusting mechanism 32. 30 is wound around the body 17. While the direction of movement of the winding position of the fiber reinforced resin 30 is switched near the end of the body portion 17 by the folding operation, the fiber reinforced resin 30 is moved by the adjusting mechanism 32 with a lower tension than the normal winding operation. 17 is wound. When the folding operation is completed, the normal winding operation is restarted, and the fiber reinforced resin 30 is wound around the body portion 17 again by the adjusting mechanism 32 with a constant tension.

図４（ｂ）に示すように、本実施形態に係るフープ巻き工程は、折り返し動作時の繊維強化樹脂３０の張力が、折り返し動作の前後の通常の巻き付け動作時の繊維強化樹脂３０の張力よりも低くなるように調整されている。通常の巻き付け動作では、繊維強化樹脂３０の巻き付け方向Ｄ１の傾きが変わらないため、繊維強化樹脂３０の幅方向の張力バランスを崩すことなく胴体部１７に繊維強化樹脂３０が巻き付けられる。 As shown in FIG. 4B, in the hoop winding step according to the present embodiment, the tension of the fiber-reinforced resin 30 during the folding operation is higher than the tension of the fiber-reinforced resin 30 during the normal winding operation before and after the folding operation. Has also been adjusted to be lower. In the normal winding operation, since the inclination of the winding direction D1 of the fiber reinforced resin 30 does not change, the fiber reinforced resin 30 is wound around the body 17 without breaking the tension balance in the width direction of the fiber reinforced resin 30.

折り返し動作では、胴体部１７の他端部の手前で繊維強化樹脂３０の巻き付け位置の移動速度が低下し始めて、繊維強化樹脂３０の巻き付け方向Ｄ１の傾きが中心軸ＣＸに垂直な方向Ｄ２（図２参照）に近づけられる。このとき、繊維強化樹脂３０の巻き付け位置の移動速度の低下の開始に合わせて、調整機構３２によって繊維強化樹脂３０の張力が低下し始めるように調整される。胴体部１７の他端部で繊維強化樹脂３０の巻き付け位置の移動方向が逆向きになると、繊維強化樹脂３０の巻き付け位置の移動速度が上昇し始めて、繊維強化樹脂３０の巻き付け方向Ｄ１が逆転する。このとき、繊維強化樹脂３０の巻き付け位置の移動速度の上昇の開始に合わせて、調整機構３２によって繊維強化樹脂３０の張力が上昇し始めるように調整される。 In the folding operation, the moving speed of the winding position of the fiber reinforced resin 30 starts to decrease just before the other end of the body portion 17, and the inclination of the winding direction D1 of the fiber reinforced resin 30 in the direction D2 perpendicular to the central axis CX (see FIG. 2). At this time, the adjustment mechanism 32 adjusts the tension of the fiber reinforced resin 30 to start decreasing in accordance with the start of the decrease in the moving speed of the winding position of the fiber reinforced resin 30. When the moving direction of the winding position of the fiber reinforced resin 30 is reversed at the other end of the body portion 17, the moving speed of the winding position of the fiber reinforced resin 30 starts to increase, and the winding direction D1 of the fiber reinforced resin 30 is reversed. . At this time, the adjusting mechanism 32 adjusts the tension of the fiber reinforced resin 30 so that the tension of the fiber reinforced resin 30 starts to increase as the moving speed of the winding position of the fiber reinforced resin 30 starts to increase.

このように、折り返し動作の開始直後から繊維強化樹脂３０の巻き付け方向Ｄ１の傾きが変化し始め、折り返し動作の完了後に繊維強化樹脂３０の巻き付け方向Ｄ１の傾きが逆転する。そして、折り返し動作中は、繊維強化樹脂３０の巻き付け方向Ｄ１の傾きの変化に合わせて、折り返し動作の前後よりも繊維強化樹脂３０の張力が低くなるように調整されている。繊維強化樹脂３０の巻き付け方向Ｄ１の変化に合わせて繊維強化樹脂３０の巻き付け方向Ｄ１の張力が変化するため、折り返し動作の前後において繊維強化樹脂３０の幅方向の張力バランスが緩やかに変化する。よって、図４（ｃ）に示すように、繊維強化樹脂３０の幅方向の張力バランスが崩れずに繊維強化樹脂３０の捩れが抑えられる。そのため、胴体部１７の端部外面に繊維強化樹脂３０を平らに巻き付けることが可能になって、胴体部１７の端部付近のタンク強度の低下が抑えられる。 As described above, the inclination of the winding direction D1 of the fiber reinforced resin 30 starts to change immediately after the start of the folding operation, and the inclination of the winding direction D1 of the fiber reinforced resin 30 is reversed after the completion of the folding operation. During the folding operation, the tension of the fiber reinforced resin 30 is adjusted to be lower than before and after the folding operation in accordance with the change in the inclination of the fiber reinforced resin 30 in the winding direction D1. Since the tension in the winding direction D1 of the fiber reinforced resin 30 changes in accordance with the change in the winding direction D1 of the fiber reinforced resin 30, the tension balance in the width direction of the fiber reinforced resin 30 changes gradually before and after the folding operation. Therefore, as shown in FIG. 4C, the twist of the fiber reinforced resin 30 is suppressed without breaking the tension balance in the width direction of the fiber reinforced resin 30. Therefore, the fiber reinforced resin 30 can be wrapped flat around the outer surface of the end of the body 17, and a decrease in tank strength near the end of the body 17 can be suppressed.

なお、調整機構３２は、例えば繊維強化樹脂３０の巻き付け位置が胴体部１７の端部に到達したタイミングで、繊維強化樹脂３０の張力が最小値になるように調整している。この場合、調整機構３２は、折り返しタイミングを頂点としたＶ字状の張力波形が描かれるように繊維強化樹脂３０の張力をサーボ制御している。これにより、繊維強化樹脂３０の巻き付け方向Ｄ１の傾きの変化に合わせて、繊維強化樹脂３０の張力が調整されて、折り返し動作を行う際の繊維強化樹脂３０の幅方向の張力バランスの急激な変化が抑えられている。 The adjusting mechanism 32 adjusts the tension of the fiber reinforced resin 30 to a minimum value, for example, at a timing when the winding position of the fiber reinforced resin 30 reaches the end of the body 17. In this case, the adjusting mechanism 32 servo-controls the tension of the fiber reinforced resin 30 so that a V-shaped tension waveform having the return timing at the top is drawn. Thereby, the tension of the fiber reinforced resin 30 is adjusted in accordance with the change in the inclination of the winding direction D1 of the fiber reinforced resin 30, and a sudden change in the tension balance in the width direction of the fiber reinforced resin 30 when performing the folding operation. Is suppressed.

また、フープ巻き工程は、胴体部１７の周りにのみ繊維強化樹脂３０をフープ巻きする構成に限らず、少なくとも胴体部１７の周りに繊維強化樹脂３０をフープ巻きする構成であればよい。例えば、胴体部１７から湾曲部１９側に繊維強化樹脂３０が部分的に食み出すように、ライナ１１の周りに繊維強化樹脂３０を巻き付けてもよい。湾曲部１９はライナ径を縮径するように湾曲しているため、繊維強化樹脂３０の一部が湾曲部１９側に食み出ることで捩れ易い。しかしながら、張力を緩めながら繊維強化樹脂３０が胴体部１７の端部に巻き付けられるため、繊維強化樹脂３０の一部が湾曲部１９側に食み出ても、繊維強化樹脂３０の幅方向の張力バランスが急激に変化することがない。よって、胴体部１７の端部でライナ１１の外径が縮径し始めるような形状であっても、繊維強化樹脂が捩れた状態でライナ１１に巻き付けられることがなく、胴体部１７の端部付近のタンク強度の低下が抑えられる。 Further, the hoop winding step is not limited to the configuration in which the fiber reinforced resin 30 is hoop-wound only around the body portion 17, and may be any configuration in which the fiber reinforced resin 30 is hoop-wrapped at least around the body portion 17. For example, the fiber reinforced resin 30 may be wound around the liner 11 so that the fiber reinforced resin 30 partially protrudes from the body portion 17 toward the curved portion 19. Since the curved portion 19 is curved so as to reduce the diameter of the liner, a part of the fiber reinforced resin 30 protrudes toward the curved portion 19 and is easily twisted. However, since the fiber reinforced resin 30 is wound around the end of the body portion 17 while relaxing the tension, even if a part of the fiber reinforced resin 30 protrudes toward the curved portion 19, the tension in the width direction of the fiber reinforced resin 30 is reduced. The balance does not change rapidly. Therefore, even if the outer diameter of the liner 11 starts to decrease at the end of the body 17, the fiber reinforced resin is not wound around the liner 11 in a twisted state, and the end of the body 17 is not twisted. A decrease in the strength of the nearby tank is suppressed.

また、本実施形態のフープ巻き工程は、折り返し動作で繊維強化樹脂３０に捩れを起こすことが抑えられて、胴体部１７の端部付近での張力の低下が抑えられているため、比較例のフープ巻き工程（図３（ｂ）参照）と比較して通常の巻き付け動作の平均張力を高めることができる。よって、端部の強度低下を考慮して通常の巻き付け動作で繊維強化樹脂３０の張力を低く設定する必要がなく、胴体部１７の端部以外で繊維強化樹脂３０の張力を高めて、全体としてタンク強度を高めることができる。なお、折り返し動作時の張力は、胴体部１７の端部に所定の強度を確保しつつ、繊維強化樹脂３０に弛みが生じない程度に調整されている。 In the hoop winding step of the present embodiment, the twisting of the fiber reinforced resin 30 due to the folding operation is suppressed, and the decrease in the tension near the end of the body 17 is suppressed. Compared with the hoop winding step (see FIG. 3B), the average tension of the normal winding operation can be increased. Therefore, it is not necessary to set the tension of the fiber reinforced resin 30 low by a normal winding operation in consideration of the strength reduction of the end portion, and the tension of the fiber reinforced resin 30 is increased at the portions other than the end portion of the body portion 17 as a whole. Tank strength can be increased. The tension at the time of the folding operation is adjusted so that the fiber-reinforced resin 30 does not loosen while securing a predetermined strength at the end of the body portion 17.

ここで、図５を参照して、繊維強化樹脂３０の張力と樹脂幅の関係について説明する。図５は、繊維強化樹脂３０の張力と樹脂幅の関係を示すグラフである。なお、図中の実線Ｌは、繊維強化樹脂３０の張力が低くなるほど元幅からの変形が小さくなることを示している。 Here, the relationship between the tension of the fiber reinforced resin 30 and the resin width will be described with reference to FIG. FIG. 5 is a graph showing the relationship between the tension of the fiber reinforced resin 30 and the resin width. The solid line L in the figure indicates that the lower the tension of the fiber reinforced resin 30, the smaller the deformation from the original width.

図５に示すように、幅３５ｍｍの帯状の繊維強化樹脂３０に対する張力を変えながら、ライナ１１の外面に巻き付けられた繊維強化樹脂３０の樹脂幅を測定した。この結果、繊維強化樹脂３０に対して張力４００Ｎ−３６０Ｎの張力が付与されているときには、測定値を示すプロットが幅３０ｍｍ以下の範囲に集中した。また、繊維強化樹脂３０に対して張力３４０Ｎ−３００Ｎの張力が付与されているときには、測定値を示すプロットが幅３０ｍｍよりも高い範囲に集中した。すなわち、張力３６０Ｎ以上では元幅からの変形が略５ｍｍ以上となり、張力３４０Ｎ以下では元幅からの変形が略５ｍｍ未満に抑えられている。 As shown in FIG. 5, the resin width of the fiber reinforced resin 30 wound around the outer surface of the liner 11 was measured while changing the tension on the 35 mm-width band-shaped fiber reinforced resin 30. As a result, when a tension of 400N-360N was applied to the fiber reinforced resin 30, the plots indicating the measured values were concentrated in a range of 30 mm or less in width. Also, when a tension of 340N-300N was applied to the fiber reinforced resin 30, the plot showing the measured values was concentrated in a range higher than the width of 30 mm. That is, when the tension is 360 N or more, the deformation from the original width is about 5 mm or more, and when the tension is 340 N or less, the deformation from the original width is suppressed to less than about 5 mm.

繊維強化樹脂３０の元幅からの変形は捩れを示しており、繊維強化樹脂３０の種類によって捩れの許容量は異なるが、例えば元幅からの変形が５ｍｍ以内を良品とする場合には、張力３００Ｎ以上、３５０Ｎ未満に抑えることが好ましい。特に、繊維強化樹脂３０の元幅から変形しないプロットを含む張力３００Ｎ以上、３２０Ｎ以下に抑えることがより好ましい。通常の巻き付け動作時の平均張力を４２０Ｎ（図４（ｂ）参照）として考えると、折り返し動作時の張力は、通常の巻き付け動作時の張力の７０％以上、８０％以下に抑えることが好ましく、７０％以上、７５％以下に抑えることがより好ましい。 The deformation of the fiber reinforced resin 30 from the original width indicates torsion, and the allowable amount of twist varies depending on the type of the fiber reinforced resin 30. For example, when the deformation from the original width is 5 mm or less as a non-defective product, the tension is It is preferable to suppress the pressure to 300 N or more and less than 350 N. In particular, it is more preferable that the tension including the plot that does not deform from the original width of the fiber reinforced resin 30 be 300 N or more and 320 N or less. Assuming that the average tension during the normal winding operation is 420 N (see FIG. 4B), the tension during the folding operation is preferably suppressed to 70% or more and 80% or less of the tension during the normal winding operation. It is more preferable that the content be suppressed to 70% or more and 75% or less.

続いて、タンクの製造方法について説明する。図６は、本実施の形態に係るタンクの製造方法の一例を示すフローチャートである。 Subsequently, a method of manufacturing the tank will be described. FIG. 6 is a flowchart illustrating an example of the method for manufacturing a tank according to the present embodiment.

図６に示すように、ライナ１１が準備されると、ＦＷ工法によってライナ１１の外面に繊維強化樹脂層１２の形成処理が開始される。この場合、未硬化樹脂で強化繊維を帯状に束ねた繊維強化樹脂３０が用意され、回転しているライナ１１の胴体部１７に繊維強化樹脂３０のフープ巻きを繰り返すフープ巻き工程が実施される（ステップＳ０１）。フープ巻き工程では、繊維強化樹脂３０の巻き付け位置を胴体部１７の軸方向に往復させながら、通常の巻き付け動作と折り返し動作とによって胴体部１７に繊維強化樹脂３０のフープ巻きが繰り返される。 As shown in FIG. 6, when the liner 11 is prepared, the process of forming the fiber reinforced resin layer 12 on the outer surface of the liner 11 is started by the FW method. In this case, a fiber reinforced resin 30 in which reinforcing fibers are bundled in a belt shape with an uncured resin is prepared, and a hoop winding step of repeating the hoop winding of the fiber reinforced resin 30 around the rotating body portion 17 of the liner 11 is performed ( Step S01). In the hoop winding step, the hoop winding of the fiber reinforced resin 30 around the body 17 is repeated by a normal winding operation and a folding operation while the winding position of the fiber reinforced resin 30 is reciprocated in the axial direction of the body 17.

通常の巻き付け動作では、繊維強化樹脂３０の張力を一定に調整した状態で、胴体部１７の両端部を除く中間領域に繊維強化樹脂３０が巻き付けられる。折り返し動作では、折り返し動作の前後の繊維強化樹脂３０の張力よりも低い張力で繊維強化樹脂３０が胴体部１７の端部付近に巻き付けられる。これにより、折り返し動作時の繊維強化樹脂３０の幅方向の張力バランスの変化が緩やかになって、胴体部１７の端部付近に巻き付けられる繊維強化樹脂３０の捩れが抑えられている。そして、胴体部１７に対して通常の巻き付け動作と折り返し動作が繰り返されることで、胴体部１７の外面には捩れが抑えられた状態で繊維強化樹脂３０が重ねられてフープ層Ｌ１が形成される。フープ層Ｌ１の端部で繊維強化樹脂３０の捩れが抑えられるため、胴体部１７の端部においてタンク強度の低下が抑えられている。 In a normal winding operation, the fiber reinforced resin 30 is wound around an intermediate region excluding both ends of the body portion 17 with the tension of the fiber reinforced resin 30 being adjusted to be constant. In the folding operation, the fiber reinforced resin 30 is wound around the end of the body 17 with a tension lower than the tension of the fiber reinforced resin 30 before and after the folding operation. Thereby, the change of the tension balance in the width direction of the fiber reinforced resin 30 at the time of the folding operation becomes gentle, and the twist of the fiber reinforced resin 30 wound around the end of the body 17 is suppressed. Then, by repeating the normal winding operation and the folding operation on the body portion 17, the fiber reinforced resin 30 is overlapped on the outer surface of the body portion 17 in a state where the twist is suppressed, and the hoop layer L1 is formed. . Since the twist of the fiber reinforced resin 30 is suppressed at the end of the hoop layer L1, a decrease in the tank strength at the end of the body 17 is suppressed.

次に、胴体部１７のフープ層Ｌ１の外側に１０°から６０°の巻き付け角度で繊維強化樹脂３０を巻き付けるヘリカル巻き工程が実施される（ステップＳ０２）。ヘリカル巻き工程では、フープ層Ｌ１およびフープ層Ｌ１から露出した湾曲部１８、１９を含むライナ１１全体に対して繊維強化樹脂３０が螺旋状に繰り返し巻き付けられてヘリカル層Ｌ２が形成される。ＦＷ工法によってライナ１１の外面に繊維強化樹脂３０が巻き付け終わると、加熱炉にて加熱されて強化繊維に含浸された未硬化樹脂が硬化される硬化工程が実施される（ステップＳ０３）。これにより、繊維強化樹脂３０同士が接着されて、ライナ１１の外側に繊維強化樹脂層１２が形成される。 Next, a helical winding step of winding the fiber reinforced resin 30 around the hoop layer L1 of the body portion 17 at a winding angle of 10 ° to 60 ° is performed (Step S02). In the helical winding step, the fiber reinforced resin 30 is repeatedly spirally wound around the entire liner 11 including the hoop layer L1 and the curved portions 18 and 19 exposed from the hoop layer L1, thereby forming the helical layer L2. After the fiber reinforced resin 30 is wound around the outer surface of the liner 11 by the FW method, a curing step of heating the uncured resin impregnated in the reinforcing fibers by heating in a heating furnace is performed (Step S03). Thereby, the fiber reinforced resins 30 are adhered to each other, and the fiber reinforced resin layer 12 is formed outside the liner 11.

以上のように、本実施形態のタンクの製造方法では、ライナ１１の胴体部１７に対するフープ巻き工程の折り返し動作を行う際に、折り返し動作の前後の張力よりも低い張力で帯状の繊維強化樹脂がライナに巻き付けられる。このため、折り返し動作による繊維強化樹脂３０の捩れが少なくなって、繊維強化樹脂３０の折り返し位置におけるタンク強度の低下を抑えることができる。 As described above, in the tank manufacturing method according to the present embodiment, when performing the folding operation of the hoop winding process on the body portion 17 of the liner 11, the band-shaped fiber reinforced resin is applied with a tension lower than the tension before and after the folding operation. Wrapped around the liner. For this reason, the twist of the fiber reinforced resin 30 due to the folding operation is reduced, and a decrease in the tank strength at the folded position of the fiber reinforced resin 30 can be suppressed.

なお、本実施形態では、胴体部１７の両端部付近で折り返し動作を実施する構成にしたが、胴体部１７の両端部間の任意の位置で折り返し動作が行われてもよい。また、フープ巻き工程を例示して説明したが、本開示の技術は胴体部１７の両端付近で繊維強化樹脂３０を巻き付ける構成に適用可能であり、例えば、ヘリカル巻きを行っている最中に胴体部１７の両端付近で繊維強化樹脂３０の張力を低下させるようにしてもよい。 In the present embodiment, the folding operation is performed near both ends of the body 17, but the folding operation may be performed at any position between both ends of the body 17. Although the hoop winding process has been described as an example, the technology of the present disclosure can be applied to a configuration in which the fiber reinforced resin 30 is wound near both ends of the body portion 17, for example, while the helical winding is being performed. The tension of the fiber reinforced resin 30 may be reduced near both ends of the portion 17.

また、本実施形態について説明したが、他の実施形態として実施形態および変形例を全体的又は部分的に組み合わせたものでもよい。さらに、本開示の技術は本実施形態に限定されるものではなく、技術的思想の趣旨を逸脱しない範囲において様々に変更、置換、変形されてもよい。さらには、技術の進歩または派生する別技術によって、技術的思想を別の仕方で実現することができれば、その方法を用いて実施されてもよい。したがって、特許請求の範囲は、技術的思想の範囲内に含まれ得る全ての実施態様をカバーしている。 Further, although the present embodiment has been described, another embodiment may be a combination of the embodiment and the modified examples in whole or in part. Further, the technology of the present disclosure is not limited to the present embodiment, and may be variously changed, replaced, or modified without departing from the spirit of the technical idea. Furthermore, if the technical idea can be realized in another way by the advancement of the technology or another technology derived therefrom, the method may be implemented using that method. Therefore, the claims cover all embodiments that can be included within the scope of the technical idea.

１０：高圧タンク、１１：ライナ、１７：胴体部、３０：繊維強化樹脂 10: High pressure tank, 11: Liner, 17: Body, 30: Fiber reinforced resin

Claims

A method for manufacturing a tank for winding a belt-like fiber reinforced resin while applying tension to a rotating liner,
While reciprocating the winding position of the fiber reinforced resin in the axial direction of the cylindrical body of the liner, a hoop winding step of repeating hoop winding of the fiber reinforced resin at least on the body,
In the hoop winding step, when performing a folding operation to reverse the moving direction of the winding position of the fiber reinforced resin, the fiber reinforced resin with a tension lower than the tension of the fiber reinforced resin before and after the folding operation. A method for manufacturing a tank, wherein the tank is wound around the liner.