Pressure vessel

Abstract

A pressure vessel for a fluid comprises a plurality of main body sections, each having a tubular shape extending along a first direction and arranged orthogonally to the first direction along a second direction, and one or more bending sections, each having a tubular shape, extending between two adjacent end sections of the main body sections and connecting the main body sections in series, as well as a reinforcing layer covering the outer circumferential walls of the main body sections and the outer circumferential walls of the one or more bending sections and comprising a carbon fiber. The carbon fiber content per unit length in one direction of extension of the reinforcing layer in the bending section is lower than the carbon fiber content per unit length in one direction of extension of the reinforcing layer in the main body section.

Description

Background of the invention 1. Field of the invention

[0001] The technology disclosed in this specification relates to a pressure vessel. 2. Description of the relevant state of the art

[0002] JP 2018-519480 A discloses a pressure vessel for a fluid. The pressure vessel comprises a plurality of main body sections, each having a tubular shape extending in a first direction and arranged orthogonally to the first direction in a second direction, and one or more bending sections, each having a tubular shape, extending between two adjacent end sections of the main body sections and connecting the main body sections in series. Summary of the invention

[0003] In the pressure vessel of JP 2018-519480 A, the bending section is provided by bending a linear tubular section. To increase the strength of the fluid-filled pressure vessel, a configuration is considered in which the outer circumferential walls of the main body sections and the outer circumferential walls of one or more bending sections are covered with a reinforcing layer. However, the reinforcing layer covering the outer circumferential wall of the section of the linear tubular part corresponding to the bending section makes bending this section more difficult.

[0004] The present specification provides a technology that is capable of increasing the strength of a pressure vessel and of providing a curved section of the pressure vessel in a simple manner.

[0005] In a first aspect, the present disclosure relates to a pressure vessel for a fluid. The pressure vessel comprises a plurality of main body sections, each having a tubular shape extending in a first direction and arranged along a second direction orthogonal to the first direction, as well as one or more bent sections or bending sections, each having a tubular shape, extending between two adjacent end sections of the main body sections and connecting the main body sections in series, and a reinforcing layer covering the outer circumferential walls of the main body sections and the outer circumferential walls of the one or more bent sections and comprising a carbon fiber.The carbon fiber content per unit length in one direction of the reinforcement layer in the bending section is lower than the carbon fiber content per unit length in one direction of the reinforcement layer in the main body section.

[0006] According to the above configuration, the section of the linear tubular part corresponding to the bending section can be bent more easily compared to a configuration where the carbon fiber content per unit length in the extension direction of the reinforcing layer in the bending section is the same as the carbon fiber content per unit length in the extension direction of the reinforcing layer in the main body section. Therefore, the strength of the pressure vessel can be increased, and the bending section of the pressure vessel can be provided in a simple manner.

[0007] In a second aspect, the carbon fiber content per unit volume of the reinforcing layer in the bending section can be the same as the carbon fiber content per unit volume of the reinforcing layer in the main body section. The thickness of the reinforcing layer in the bending section can be thinner than the thickness of the reinforcing layer in the main body section.

[0008] According to the above configuration, the reinforcement layer can be provided in a simple manner, compared to a configuration in which the carbon fiber content per unit volume of the reinforcement layer in the bending section and the carbon fiber content per unit volume of the reinforcement layer in the main body section are different.

[0009] In a third aspect, in the second aspect, the reinforcing layer can correspond, at least in the main body sections, to a laminated structure of carbon fiber layers, and the number of carbon fiber layers in the bending section can be smaller than the number of carbon fiber layers in the main body section.

[0010] According to the above configuration, the strength of the pressure vessel can be increased, and the bending section of the pressure vessel can be provided in a simple manner.

[0011] In a fourth aspect, the carbon fiber content per unit volume of the reinforcement layer in the bending section may be lower than the carbon fiber content per unit volume of the reinforcement layer in the main body section.

[0012] According to the above configuration, the strength of the pressure vessel can be increased, and the bending section of the pressure vessel can be provided in a simple manner. Brief description of the illustrations

[0013] Features, advantages, and the technical and industrial significance of exemplary embodiments of the invention are described below with reference to the accompanying figures, in which the same symbols denote the same elements, and wherein: Fig. 1 a sectional view of a pressure vessel 2 is; Fig. 2 an enlarged view of Section II in Fig. 1 is; Fig. 3 is a view showing a tubular element 102 before it is wrapped with carbon fiber; Fig. 4 is a view showing a method for winding the carbon fiber around the tubular element 102; and Fig. 5 is an enlarged view of a pressure vessel 202 according to a second embodiment. Detailed description of embodiments: First embodiment

[0014] A pressure vessel 2 for a fluid is defined with reference to the Fig. 1 and Fig. 2 described. The pressure vessel 2 is, for example, mounted on a fuel cell electric vehicle (not shown). The pressure vessel 2 is filled with high-pressure hydrogen gas, which is used to generate electricity in the fuel cell electric vehicle.

[0015] As in Fig. As shown in Figure 1, the pressure vessel 2 comprises a plurality of main body sections 10, a plurality of bending sections 12, and a reinforcing layer 14. For the sake of simplicity, in the following description, the direction in which the main body sections 10 are arranged is referred to as the "left-right direction," and the longitudinal direction of the main body sections 10, that is, the direction orthogonal to the left-right direction, is referred to as the "forward-backward direction."

[0016] Each of the main body sections 10 extends along the forward-backward direction. Each of the main body sections 10 has a tubular shape. The main body section 10 comprises a first cylindrical section 20, a first frustoconical section 22, and a second frustoconical section 24. The first cylindrical section 20 extends parallel to the forward-backward direction. The first cylindrical section 20 has a cylindrical shape. The first frustoconical section 22 is connected to the front end section of the first cylindrical section 20. The first frustoconical section 22 has a frustoconical shape. The first frustoconical section 22 is inclined such that its outer and inner diameters decrease towards the front. The second frustoconical section 24 is connected to the rear end section of the first cylindrical section 20.The second frustoconical section 24 has a frustoconical shape. The second frustoconical section 24 is inclined such that its outer and inner diameters decrease towards the rear.

[0017] Each of the bending sections 12 has a cylindrical shape. Each of the bending sections 12 is provided with a circular section perpendicular to the direction of extension. Of the bending sections 12, each bending section 12 located on the front of the pressure vessel 2 extends between the front end sections of two adjacent main body sections 10. For example, the rightmost bending section 12 on the front of the pressure vessel 2 extends forward from the front end section of the rightmost main body section 10, bends and extends to the left, and continues to bend to extend to the front end section of the adjacent main body section 10.

[0018] Each bend section 12 located at the rear of the pressure vessel 2 extends from the bend sections 12 between the rear end sections of two adjacent main body sections 10. For example, the rightmost bend section 12 at the rear of the pressure vessel 2 extends from the rear end section of the second main body section 10 from the right rearward, bends and extends to the left, and bends further to extend to the rear end section of the adjacent main body section 10. The flow path axis of the bend section 12 in Fig. 1 has a semicircular arc shape.

[0019] The bending section 12 is connected to the front end section of the main body section 10 located on the far right and to the front end section of the main body section 10 located on the far left, and the bending section 12 is connected to both the front and rear end sections of other main body sections 10. In this way, the main body sections 10 are connected in series by the bending sections 12.

[0020] The reinforcement layer 14 comprises a main body section reinforcement layer 30, which covers the outer circumferential wall of the main body section 10, and a bending section reinforcement layer 32, which covers the outer circumferential wall of the bending section 12. The main body section reinforcement layer 30 and the bending section reinforcement layer 32 consist of a resin containing carbon fiber. As an example, the main body section reinforcement layer 30 and the bending section reinforcement layer 32 are made of CFRP. The carbon fiber content per unit volume in the extension direction of the bending section reinforcement layer 32 is equal to the carbon fiber content per unit volume in the extension direction of the main body section reinforcement layer 30.This means that a first density of the carbon fiber in the bending section reinforcement layer 32 is equal to a second density of the carbon fiber in the main body section reinforcement layer 30. As in . Fig. As shown in Figure 2, the main body section reinforcement layer 30 is a laminated structure of carbon fiber layers. The main body section reinforcement layer 30 is produced by laminating three carbon fiber layers. The bending section reinforcement layer 32 is a single-layer structure consisting of one carbon fiber layer. Therefore, the carbon fiber content per unit length in the extension direction of the bending section reinforcement layer 32 is lower than the carbon fiber content per unit length in the extension direction of the main body section reinforcement layer 30. Furthermore, the thickness of the bending section reinforcement layer 32 is thinner than the thickness of the main body section reinforcement layer 30.Furthermore, the carbon fiber weight per unit length in the extension direction of the bending section reinforcement layer 32 is lower than the carbon fiber weight per unit length in the extension direction of the main body section reinforcement layer 30. Method for manufacturing pressure vessel 2

[0021] A method for manufacturing the pressure vessel 2 is described with reference to the Fig. 3 and Fig. 4 described.

[0022] First, as in Fig. Figure 3 shows a tubular element 102 provided along an axis A. As an example, the tubular element 102 is provided in one piece by extrusion. The tubular element 102 comprises a plurality of main body sections 10 and a plurality of second cylindrical sections 112.

[0023] Next, as in Fig. Figure 4 shows a thread-like carbon fiber wound around the outer circumferential walls of the main body sections 10 and the outer circumferential walls of the second cylindrical sections 112. As an example, the carbon fiber is wound in a spiral. First, the carbon fiber is wound from the left end section to the right end section of the main body section 10 on the left side of Fig. 4 ((A) of Fig. 4) wound. Next, the carbon fiber is wound from the right end section to the left end section of the main body section 10 ((B) in Fig. 4) Next, the carbon fiber is wound from the left end section to the right end section of the main body section 10 ((C) in Fig. 4) This provides three carbon fiber layers on the outer circumferential wall of a first main body section 10A. Subsequently, the carbon fiber is wound from the left end section to the right end section of the second cylindrical section 112 ((D) in Fig. 4) This provides a single layer of carbon fiber on the outer circumferential wall of the second cylindrical section 112. Then (A) to (D) of Fig. 4 repeated to provide three carbon fiber layers on the outer circumferential walls of the main body sections 10 and a single carbon fiber layer on the outer circumferential walls of the second cylindrical sections 112.

[0024] Next, the second cylindrical sections 112 are bent to provide the bending sections 12 (see Fig. 1) In this way, the Fig. 1. Pressure vessel 2 shown.

[0025] As described above, the bending section 12 (see Fig. 1) provided by bending the second cylindrical section 112. However, if three carbon fiber layers, similar to those on the outer circumferential wall of the main body section 10, were provided on the outer circumferential wall of the second cylindrical section 112, a relatively large force would be required to bend the second cylindrical section 112. For this reason, it is desirable for the second cylindrical section 112 to be provided with a configuration that is easy to bend. Therefore, the second cylindrical section 112 is provided with a single carbon fiber layer. This facilitates the bending of the second cylindrical section 112 compared to a configuration where the outer circumferential wall of the second cylindrical section 112 is provided with three carbon fiber layers, similar to those of the outer circumferential wall of the main body section 10. Effects of the embodiment

[0026] As described above, the pressure vessel 2 comprises the main body sections 10, each of which has a tubular shape extending along the forward-backward direction (an example of the “first direction”) and is arranged along the left-right direction (an example of the “second direction”), the bending sections 12, each of which has a tubular shape, extends between two adjacent end sections of the main body sections 10 and connects the main body sections 10 in series, and the reinforcing layer 14, which covers the outer circumferential walls of the main body sections 10 and the outer circumferential walls of the bending sections 12 and comprises the carbon fiber.The carbon fiber content per unit length in the extension direction of the reinforcement layer 14 in the bending section 12 is lower than the carbon fiber content per unit length in the extension direction of the reinforcement layer 14 in the main body section 10.

[0027] According to the above configuration, the section of the linear tubular part corresponding to the bending section 12 can be bent in a simple manner, compared to a configuration where the carbon fiber content per unit length in the extension direction of the reinforcing layer 14 in the bending section 12 is equal to the carbon fiber content per unit length in the extension direction of the reinforcing layer 14 in the main body section 10. Therefore, the strength of the pressure vessel 2 can be increased, and the bending section 12 of the pressure vessel 2 can be provided in a simple manner.

[0028] Furthermore, the carbon fiber content per unit volume of the reinforcing layer 14 in the bending section 12 is equal to the carbon fiber content per unit volume of the reinforcing layer 14 in the main body section 10. The thickness of the reinforcing layer 14 in the bending section 12 is thinner than the thickness of the reinforcing layer 14 in the main body section 10.

[0029] According to the above configuration, the reinforcement layer 14 can be provided in a simple manner compared to a configuration in which the carbon fiber content per unit volume of the reinforcement layer 14 in the bending section 12 and the carbon fiber content per unit volume of the reinforcement layer 14 in the main body section 10 are different.

[0030] Furthermore, the reinforcement layer 14 corresponds, at least in the main body sections 10, to a laminated structure of carbon fiber layers, and the number of carbon fiber layers in the bending section 12 is smaller than the number of carbon fiber layers in the main body sections 10.

[0031] According to the above configuration, the strength of the pressure vessel 2 can be increased, and the bending section 12 of the pressure vessel 2 can be provided in a simple manner. Second embodiment

[0032] A pressure vessel 202 in a second embodiment is described with reference to Fig. 5 described. In the pressure vessel 202 of the present embodiment, the configuration of a reinforcing layer 214 is different from the configuration of the reinforcing layer 14 of the pressure vessel 2 of the first embodiment.

[0033] The reinforcement layer 214 comprises a main body section reinforcement layer 230, which covers the outer circumferential wall of the main body section 10, and a bend section reinforcement layer 232, which covers the outer circumferential wall of the bend section 12. The carbon fiber content per unit volume in the longitudinal direction of the bend section reinforcement layer 232 is lower than the carbon fiber content per unit volume in the longitudinal direction of the main body section reinforcement layer 230. That is, the carbon fiber density in the bend section reinforcement layer 232 is lower than the carbon fiber density in the main body section reinforcement layer 230. The main body section reinforcement layer 230 is a laminated structure consisting of a single layer of carbon fiber. The bend section reinforcement layer 232 is a single-layer structure consisting of a single layer of carbon fiber.The thickness of the bending section reinforcement layer 232 is equal to the thickness of the main body section reinforcement layer 230. The carbon fiber content per unit length in the extension direction of the bending section reinforcement layer 232 is lower than the carbon fiber content per unit length in the extension direction of the main body section reinforcement layer 230. Furthermore, the carbon fiber content per unit length in the extension direction of the bending section reinforcement layer 232 is lower than the carbon fiber content per unit length in the extension direction of the main body section reinforcement layer 230. Additionally, the carbon fiber weight per unit length in the extension direction of the bending section reinforcement layer 232 is lower than the carbon fiber weight per unit length in the extension direction of the main body section reinforcement layer 230.In one modification, if the carbon fiber content per unit length in the extension direction of the bending section reinforcement layer 232 is lower than the carbon fiber content per unit length in the extension direction of the main body section reinforcement layer 230, the thickness of the bending section reinforcement layer 232 can be greater than the thickness of the main body section reinforcement layer 230.

[0034] As described above, the carbon fiber content per unit volume in the reinforcement layer 214 in the bending section 12 is lower than the carbon fiber content per unit volume in the reinforcement layer 214 in the main body section 10.

[0035] According to the above configuration, the strength of the pressure vessel 2 can be increased, and the bending section 12 of the pressure vessel 2 can be provided in a simple manner.

[0036] Although the embodiments have been described in detail above, these are merely examples and do not limit the scope of protection of the claims. The technology described in the claims comprises various modifications and variations of the specific examples presented above. First modification

[0037] The number of main body sections 10, arranged in a left-right direction, can be two to five, or even seven or more. Second modification

[0038] The cross-sectional shape perpendicular to the extension direction of the main body section 10 and the cross-sectional shape perpendicular to the extension direction of the bending section 12 are not limited to a circular shape and can correspond to an elliptical shape, an oval shape, a square shape or the like. Third modification

[0039] In the first and second embodiments, the bending section reinforcement layers 32, 232 can correspond to a laminated structure of carbon fiber layers. Fourth modification

[0040] In the first and second embodiments, the carbon fiber can be wound by braiding. Fifth modification

[0041] In the first and second embodiments, the bending section reinforcement layers 32, 232 can be provided at the end sections in the extension direction of the bending section 12 with the same configuration as the main body section reinforcement layers 30, 230.

[0042] The technical elements described in this specification or in the illustrations have technical benefits, either individually or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Furthermore, the technology illustrated by way of example in this specification or in the illustrations can simultaneously achieve a plurality of purposes, the achievement of any one of these purposes itself having a technical benefit. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2018-519480 A [0002, 0003]

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