Pressure vessel and method of manufacturing a pressure vessel

Abstract

The present invention is characterized by comprising: a hollow inner liner (2) having a pair of protruding portions (23A), (23B) protruding in directions away from each other; a pair of interface portions (4A), (4B) combined with the pair of protruding portions (23A), (23B) by a fastening structure accompanying rotation; and a fiber reinforced resin layer (3) formed by winding fibers around outer peripheral surfaces of the inner liner (2) and the interface portions (4A), (4B), and the fastening directions in the combination of the pair of protruding portions (23A), (23B) and the interface portions (4A), (4B) are set to directions in which each of the interface portions (4A), (4B) is fastened by the pair of protruding portions (23A), (23B) when the fibers are wound around the outer surface of the inner liner (2).

Description

Technical Field

[0001] This invention relates to pressure vessels and methods for manufacturing pressure vessels. Background Technology

[0002] A pressure vessel is known, comprising: a liner, a body for containing gas or liquid, and a pair of protrusions extending outward from the body; a metal interface portion disposed on the outer periphery of the protrusions; and a fiber-reinforced resin layer covering the liner and the interface portion (Patent Document 1). For example, when the fiber-reinforced resin layer is formed by winding, the interface portion and the liner are rotated integrally by rotating a drive shaft that engages with the interface portion, while the fiber-reinforced resin is wound around the outer periphery of the liner.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent document 1: Japanese Patent Application Publication No. 2009-58111.

[0006] Patent Document 2: Japanese Patent Application Publication No. 2017-122464. Summary of the Invention

[0007] The problem the invention aims to solve

[0008] In conventional pressure vessels, as described in Patent Document 1, a threaded structure is used to connect a pair of protrusions to an interface. In such threaded structures, the threads are all right-hand threads (or all left-hand threads). Therefore, for example, if tension is applied to the fiber in one direction during winding, one of the protrusions becomes the direction of tightening the interface, while the other becomes the direction of loosening. This results in the problem that during winding, the other interface rotates in the loosening direction relative to the liner, making secure assembly difficult. Alternatively, as described in Patent Document 2, a method exists to prevent relative rotation of the interface relative to the liner by providing rotation-limiting parts such as protrusions and recesses at the interface. However, if the interface structure becomes complex, it can easily lead to poor molding and increased production costs.

[0009] The present invention is proposed from the viewpoint that it aims to provide a pressure vessel and a method for manufacturing a pressure vessel that prevents relative rotation with respect to the liner interface during manufacturing.

[0010] Solution to the problem

[0011] To address the aforementioned issues, the present invention is characterized by comprising: a hollow liner having a pair of protrusions projecting in a mutually distancing direction; a pair of interface portions joined to the pair of protrusions by a fastening structure that accompanies rotation; and a fiber-reinforced resin layer formed by winding fibers around the outer peripheral surfaces of the liner and the interface portions, wherein the fastening direction in the joining of the pair of protrusions and the interface portions is set such that, when the fibers are wound around the outer surface of the liner, each of the interface portions is fastened by the pair of protrusions.

[0012] Furthermore, the present invention is a method for manufacturing a pressure vessel, the pressure vessel having: a hollow liner having a pair of protrusions projecting in a mutually distancing direction; and a pair of interface portions connected to the pair of protrusions by a fastening structure that accompanies rotation. The method for manufacturing the pressure vessel is characterized by comprising: a fastening step in which each of the interface portions is respectively fastened to the pair of protrusions; and a fiber-reinforced resin layer forming step in which the liner is rotated and fibers are wound around the outer peripheral surface of the liner to form a fiber-reinforced resin layer. In the fiber-reinforced resin layer forming step, a drive shaft is fitted into the pair of interface portions, and while the drive shaft and the interface portions are rotated synchronously to wind the fibers around the outer surface of the liner, the interface portions and the protrusions are formed such that each of the interface portions is fastened by the pair of protrusions.

[0013] According to the present invention, no special shape is designed for the liner or the interface, which can prevent the interface from rotating relative to the liner during manufacturing.

[0014] Furthermore, preferably, the fastening structure of the pair of protrusions and the interface has a threaded structure, and is formed such that the fastening direction of the threaded engagement of one of the protrusions and the interface is opposite to the fastening direction of the threaded engagement of the other protrusion and the interface.

[0015] According to the present invention, a simple structure can prevent the interface from rotating relative to the liner.

[0016] Invention Effects

[0017] According to the pressure vessel and the method for manufacturing the pressure vessel of the present invention, it is possible to prevent the interface portion from rotating relative to the liner during manufacturing. Attached Figure Description

[0018] Figure 1 This is a side sectional view showing a pressure vessel according to an embodiment of the present invention.

[0019] Figure 2 This is an enlarged side cross-sectional view showing the connection structure between the inner lining and the interface on one side.

[0020] Figure 3 It means Figure 2 A side view of the direction of thread cutting in the fastening structure.

[0021] Figure 4 This is an enlarged side cross-sectional view showing the connection structure between the lining and the interface on the other side.

[0022] Figure 5 It means Figure 4 A side view of the direction of thread cutting in the fastening structure.

[0023] Figure 6 It is a diagram showing the state of fibers wrapped around the outer periphery of the lining.

[0024] Figure 7 This is a comparison table showing the effects of the pressure vessel involved in this embodiment. Detailed Implementation

[0025] Pressure vessels involved in the implementation methods

[0026] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Furthermore, in the description of the drawings, the same reference numerals are used for the same elements, and repeated descriptions are omitted where appropriate.

[0027] like Figure 1 As shown, the pressure vessel 1 according to this embodiment is used as a container for storing low-pressure gases such as LPG, high-pressure gases such as hydrogen, and other fluids. Figure 1 As shown, the pressure vessel 1 of the present invention includes an inner liner 2, a fiber-reinforced resin layer 3, and interface portions 4A and 4B.

[0028] The inner liner 2 includes: a cylindrical body 21; rounded tops 22, 22 formed at both ends of the body 21; and protrusions 23A, 23B protruding from the rounded tops 22, 22 in mutually distancing directions. The inner liner 2 is formed using resin materials such as high-density polyethylene (HDPE), polyamide, polyketone, and polyphenylene sulfide (PPS) through injection molding, blow molding, or the like.

[0029] The dome 22, 22 are continuously formed from both ends of the body 21, and are sections that narrow towards the ends. On the dome 22, 22 are protruding portions 23A, 23B, which are approximately cylindrical and project outwards respectively. Protrusions 23A, 23B are for connection to interface portions 4A, 4B. Details of the connection structure between the protrusions 23A, 23B and the interface portions 4A, 4B will be described later.

[0030] The fiber-reinforced resin layer 3, for example, is formed of FRP (fiber-reinforced resin) and serves to enhance the compressive strength of the liner 2. The fiber-reinforced resin layer 3 is formed on the outer surface of the liner 2 and the interface portions 4A and 4B, for example, by a winding method in which the resin is cured after being wound around a bundle of resin-impregnated fibers.

[0031] Interface parts 4A and 4B are components externally fitted into the protrusions 23A and 23B of the inner liner 2, and are used for gas injection and discharge. Interface parts 4A and 4B are formed using high-strength metal materials such as aluminum alloy or stainless steel alloy, for inserting and installing valves, etc. In the fiber-reinforced resin layer forming process described later, the drive shaft V is inserted into interface parts 4A and 4B (see reference). Figure 6 The inner liner 2 is rotated around the drive shaft V to wind the fibers, thereby forming a fiber-reinforced resin layer 3.

[0032] like Figure 2 As shown, the interface portion 4A includes a cylindrical portion 44 and a flange portion 45. The cylindrical portion 44 is cylindrical and extends from the flange portion 45. The flange portion 45 is a portion that extends outward in a plate-like manner throughout the circumference. The flange portion 45 is disposed within a recess 24 formed in the domed top 22. The outer surface of the flange portion 45 is flush with the outer surface of the domed top 22. Figure 4 As shown, the interface portion 4B includes a cylindrical portion 44 and a flange portion 45. The interface portion 4B is the same as the interface portion 4A except for the internal thread formed on the inner circumferential surface.

[0033] (Fastening structure)

[0034] Next, the fastening structure between the inner liner 2 and the interface parts 4A and 4B will be explained. First, the interface part 4A side will be explained.

[0035] like Figure 3 As shown, an external thread (right-hand thread) S1 is formed on the outer peripheral surface of the protrusion 23A. That is, as it moves from the front end (upper side of the figure) to the base end (lower side of the figure), the thread teeth rotate clockwise. On the other hand, an internal thread (right-hand thread) S2 is formed on the inner peripheral surface of the interface portion 4A. That is, as it moves from the front end (upper side of the figure) to the base end (lower side of the figure), the thread groove rotates clockwise. By screwing the protrusion 23A and the interface portion 4A together, a fastening structure 43 is formed. Furthermore, although the fastening structure 43 is a threaded connection in this embodiment, any structure that involves rotation is acceptable, such as a cam-locking type.

[0036] like Figure 5As shown, an external thread (left-hand thread) S3 is formed on the outer peripheral surface of the protrusion 23B. That is, as it moves from the front end (upper side of the figure) to the base end (lower side of the figure) of the protrusion 23B, the thread teeth rotate counterclockwise. On the other hand, an internal thread (left-hand thread) S4 is formed on the inner peripheral surface of the interface portion 4B. That is, as it moves from the front end (upper side of the figure) to the base end (lower side of the figure) of the interface portion 4B, the thread groove rotates counterclockwise. By screwing the protrusion 23B and the interface portion 4B together, a fastening structure 48 is formed. Furthermore, the fastening structure 48 is a threaded connection in this embodiment, but any structure that involves rotation is acceptable, such as a cam-locking type.

[0037] Method for manufacturing pressure vessels involved in the embodiments

[0038] Next, the manufacturing method of pressure vessel 1 will be described. The manufacturing method of the pressure vessel according to this embodiment includes a preparation process, a fastening process, and a fiber-reinforced resin layer formation process.

[0039] In the preparation process, an inner liner 2 with protrusions 23A and 23B and interface portions 4A and 4B are formed. The inner liner 2 is formed using a molding die, for example, by blow molding. As described above, an external thread (right-hand thread) S1 is formed on the outer peripheral surface of the protrusion 23A, and an external thread (left-hand thread) S3 is formed on the outer peripheral surface of the protrusion 23B. As described above, an internal thread (right-hand thread) S2 is formed on the inner peripheral surface of the interface portion 4A, and an internal thread (left-hand thread) S4 is formed on the inner peripheral surface of the interface portion 4B.

[0040] In the fastening process, the interface portion 4A is fastened by screwing onto the protrusion 23A, and the interface portion 4B is fastened by screwing onto the protrusion 23B.

[0041] In the fiber-reinforced resin layer formation process, such as Figure 6 As shown, a fiber-reinforced resin layer 3 is formed by winding resin-impregnated fibers Z around the outer periphery of the liner 2 and the interface portions 4A and 4B. In this embodiment, as... Figure 7 As shown, the drive shaft V extending from the motor (rotary drive unit) is inserted (fitted) into the inner surfaces of the interface portions 4A and 4B. Viewed from the motor, the drive shaft V rotates clockwise, causing the drive shaft V to rotate synchronously with the interface portions 4A and 4B. Simultaneously, the inner liner 2 also rotates. While the inner liner 2 rotates clockwise around the drive shaft V, the fibers Z are wound around the outer surface of the inner liner 2.

[0042] Furthermore, the manufacturing method for the liner of the pressure vessel is not limited to the methods described above. For example, blow molding is used as an example of molding the liner 2, but it can also be molded by other molding methods such as rotational molding and injection molding.

[0043] (Effects)

[0044] Here, Figure 7 This is a comparison table showing the effects of the pressure vessel involved in this embodiment. For example... Figure 7 As shown, before the countermeasure, the interface portion 104A is fastened to one of the protrusions 123A by a right-hand thread, and the interface portion 104B is fastened to the other protrusion 123B by a right-hand thread. Therefore, when the drive shaft V is rotated, the tension of the fibers wound on the inner liner 2 sides ( Figure 7 As shown by arrow C), the rotation of the inner liner 2 is suppressed relative to the rotation of the drive shaft V / interface portions 104A and 104B. Therefore, the upper interface portion 104A acts in the tightening direction, while the lower interface portion 104B acts in the loosening direction. That is, the lower interface portion 104B becomes loose during winding, thus presenting a problem of difficulty in secure assembly.

[0045] In contrast, in this embodiment, the interface portion 4A is fastened to one of the protrusions 23A by a right-hand thread, and the interface portion 4B is fastened to the other protrusion 23B by a left-hand thread. Thus, when the drive shaft V rotates, the tension of the wound fibers is applied to the inner liner 2 side. Figure 6 , Figure 7 In the diagram (arrow C), the rotation of the inner liner 2 is suppressed relative to the rotation of the drive shaft V / interfaces 4A and 4B. Therefore, both interfaces 4A and 4B act in the tightening direction. Thus, the inner liner 2 and interfaces 4A and 4B can be securely assembled by the fiber-reinforced resin layer 3.

[0046] According to the pressure vessel 1 of this embodiment described above, the fastening directions of the interface portions 4A and 4B and the protrusions 23A and 23B are set to be the directions in which they are all tightened during winding. Therefore, without designing special shapes for the liner 2 and the interface portions 4A and 4B, it is possible to prevent the interface portions 4A and 4B from rotating relative to the liner 2 during winding.

[0047] Furthermore, the fastening structure 43 is a threaded structure in which the external thread S1 of the protrusion 23A engages with the internal thread S2 of the interface 4A. Additionally, the fastening structure 48 is a threaded structure in which the external thread S3 of the protrusion 23B engages with the internal thread S4 of the interface 4B. Thus, the fastening structure can be easily constructed.

[0048] The embodiments of the present invention have been described above, but appropriate design changes can be made without departing from the spirit of the present invention. For example, in this embodiment, the interface portion 4A is formed with a right-hand thread and the interface portion 4B is formed with a left-hand thread. However, if the rotation direction of the inner liner 2 is reversed (counterclockwise) when viewed from the motor side, the interface portion 4A may also be formed with a left-hand thread and the interface portion 4B with a right-hand thread.

[0049] Explanation of reference numerals in the attached figures

[0050] 1 Pressure Vessel

[0051] 2 Lining

[0052] 3 Fiber-reinforced resin layers

[0053] 4A and 4B interface sections

[0054] 21 torsos

[0055] 23A and 23B protrusions

Claims

1. A pressure vessel, characterized in that, have: The hollow liner has a pair of protrusions that project in a direction away from each other; A pair of interface portions are joined to a pair of protrusions by a fastening structure that accompanies rotation; as well as A fiber-reinforced resin layer is formed by winding fibers around the outer peripheral surface of the liner and the interface portion. The fastening direction of the pair of protrusions and the interface is set such that when the fiber is wound around the outer surface of the liner, each of the interface is fastened by the pair of protrusions.

2. The pressure vessel as described in claim 1, characterized in that, The fastening structure between the pair of protrusions and the interface has a threaded structure. And it is formed such that the tightening direction of the threaded engagement between the protrusion of one side and the interface portion is opposite to the tightening direction of the threaded engagement between the protrusion of the other side and the interface portion.

3. A method for manufacturing a pressure vessel, the pressure vessel having: a hollow liner having a pair of protrusions projecting in a direction away from each other; The method of manufacturing this pressure vessel, comprising a pair of interface portions, which are engaged with the pair of protrusions by a fastening structure that accompanies rotation, is characterized by including: In the fastening process, each of the aforementioned interface portions is fastened to a pair of the aforementioned protrusions; as well as In the fiber-reinforced resin layer forming process, the liner is rotated and driven to wind fibers around the outer peripheral surface of the liner to form a fiber-reinforced resin layer. In the fiber-reinforced resin layer forming process, the drive shaft is fitted into a pair of the interface portions, and the drive shaft and the interface portions are rotated synchronously to wind the fiber around the outer surface of the liner. The interface portions and the protrusions are formed in such a way that each of the interface portions is fastened by a pair of the protrusions.

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