JP7609042B2 - High Pressure Tank - Google Patents

Description

This disclosure relates to high pressure tanks.

It is known that high-pressure tanks are provided with a liner having hemispherical dome sections on both ends of a cylindrical section, a reinforcing layer formed on the surface of the liner, and a protective layer formed on the reinforcing layer. The protective layer is provided, for example, to improve the fire resistance of the tank. Patent Document 1 describes a technology in which the protective layer is made of a tubular fiber member. The tubular fiber member is arranged to cover the reinforcing layer.

JP 2021-67337 A

The inventors found a problem that when forming a protective layer by covering the dome part of the liner with a sheet-like sheet member, the dome part has a hemispherical shape, and therefore the dome part cannot be completely covered as it is. For this reason, they considered using a sheet member with multiple cuts on both ends, folding each section divided by each cut along the dome part, and covering the dome part completely. In this case, the sheet member is arranged so that adjacent parts of the sheet member overlap each other across one cut, forming a protective layer. In this case, unevenness occurs between the overlapping and non-overlapping parts of the sheet member, so if a protective member is provided around the outer periphery of the dome part of the liner to reduce impact on the tank, the protective member will only come into contact with the convex parts, which are the overlapping parts of the sheet member of the protective layer, and the area where the protective member comes into contact with the protective layer will be reduced. The inventors found a problem that this reduces the attachment strength of the protective member to the protective layer.

This disclosure has been made to solve the above-mentioned problems, and can be realized in the following forms:

(1) According to one embodiment of the present disclosure, there is provided a high-pressure tank. The high-pressure tank includes a liner having a cylindrical portion and hemispherical dome portions provided at both ends of the cylindrical portion, a reinforcing layer formed on a surface of the liner, a protective layer formed on the liner including the cylindrical portion and the dome portion and provided on the outer periphery of the reinforcing layer, the protective layer being formed by wrapping a sheet-like sheet member in the circumferential direction of the cylindrical portion, and a protective member provided on the outer periphery of the protective layer in the dome portion. The sheet member arranged on the liner has a plurality of cuts at both ends from the dome portion toward the cylindrical portion. The protective layer in the dome portion has a plurality of overlapping portions where the sheet members overlap each other by arranging the sheet members such that adjacent portions of the sheet members sandwiching each of the cuts overlap each other. The protective member has a recess capable of accommodating each of the multiple overlapping portions at a position facing each of the multiple overlapping portions, and has a protrusion at a position not facing each of the multiple overlapping portions, which is joined to a portion of the protective layer that is not one of the overlapping portions.
According to this embodiment of the high-pressure tank, the protective member has a recess that covers the overlapping portion at a position opposite the overlapping portion, so that the protrusions on both sides of the recess in the circumferential direction contact the non-overlapping portion of the protective layer. This makes it possible to prevent a reduction in the attachment strength between the protective layer and the protective member due to the thickness of the overlapping portion. Therefore, it is possible to ensure the attachment strength of the protective member to the protective layer.
(2) In the high-pressure tank of the above form, the overlapping portions are arranged in the protective layer at equally spaced angles around the central axis of the liner, and the recesses are arranged in the protective member at equally spaced angles around the central axis, and the number of the recesses may be an integer multiple of the number of the overlapping portions.
In this manner, the recess can be easily positioned at a position opposite the overlapping portion.
(3) The high-pressure tank of the above aspect may further include an adhesive layer provided between the protective layer and the protective member for fixing the protective member to the protective layer.
In this embodiment, the time required for the work can be reduced compared to when the protective member is attached to the protective layer using an adhesive.

This disclosure can be realized in various forms, for example, as a method for manufacturing a high-pressure tank of this form.

1 is a cross-sectional view showing a schematic structure of a high-pressure tank according to an embodiment of the present invention. FIG. 4 is an explanatory diagram of a sheet member forming a protective layer. FIG. 4 is an explanatory diagram of a protective layer in a dome portion. 1 is an explanatory diagram of the protective layer when viewed from the apex of the dome portion toward the outer periphery. FIG. FIG. FIG. 11 is a graph showing an example of a relationship between a diameter of a high-pressure tank and a maximum coefficient.

A. First embodiment:
1 is a cross-sectional view showing a schematic structure of a high-pressure tank 100 according to the present embodiment. The high-pressure tank 100 contains high-pressure hydrogen of, for example, 10 to 70 MPa, and is mounted on a fuel cell vehicle. The high-pressure tank 100 includes a liner 10, a nozzle 20, a reinforcing layer 30, a protective layer 40, a protective member 50, and an adhesive layer 60.

The liner 10 has a cylindrical portion 12 and two dome portions 14 of a hemispherical shape provided at both ends of the cylindrical portion 12. The liner 10 is formed of a resin having gas barrier properties against hydrogen gas, such as polyethylene, nylon, polypropylene, polyester, etc. In this embodiment, the liner 10 is made of resin, but it may be made of metal. A reinforcing layer 30 is formed on the outer periphery of the cylindrical portion 12 and the dome portion 14. In this embodiment, the nozzle 20 is provided at both longitudinal ends of the liner 10, but it may be provided at only one end. The central axis of the cylindrical portion 12 and the central axis of the dome portion 14 both coincide with the central axis Ax of the high-pressure tank 100.

The reinforcing layer 30 is formed by bundling approximately 10,000 to 40,000 pieces of glass fiber or carbon fiber (hereinafter simply referred to as "fiber"), impregnating them with a thermosetting resin such as epoxy, and winding the resulting fiber bundle around the outer surface of the liner 10 by a filament winding method. A protective layer 40 is formed on the outer surface of the reinforcing layer 30. The reinforcing layer 30 may be formed only on the cylindrical portion 12.

The protective layer 40 is formed on the liner 10 including the cylindrical portion 12 and the dome portion 14. The protective layer 40 is formed by wrapping a sheet-like sheet member made of a thermoplastic resin such as polypropylene or polyvinyl chloride around the outer periphery of the reinforcing layer 30 in the circumferential direction of the cylindrical portion 12. More specifically, the protective layer 40 is formed by wrapping the sheet member in the circumferential direction of the cylindrical portion 12 and folding both ends of the sheet member to follow the shape of the dome portion 14, so as to completely cover the dome portion 14. A detailed description of the protective layer 40 in the dome portion 14 will be given later. In this embodiment, the thickness of the sheet member forming the protective layer 40 is about 1.75 mm. The thickness of the sheet portion may be larger or smaller than this.

The protective member 50 is provided on the outer periphery of the protective layer 40 in the dome portion 14. The protective member 50 is a member for mitigating impacts on the high-pressure tank 100. The protective member 50 is formed, for example, from urethane. The protective member 50 is formed in a roughly hemispherical shape so as to conform to the shape of the dome portion 14, and is fixed onto the protective layer 40 by an adhesive layer 60. The protective member 50 is provided on both dome portions 14, but may be provided on only one of them.

The adhesive layer 60 is provided between the protective layer 40 and the protective member 50. The adhesive layer 60 is formed, for example, from a tape having adhesive properties on both sides (hereinafter referred to as "double-sided tape"). The adhesive layer 60 fixes the protective member 50 to the protective layer 40.

Figure 2 is an explanatory diagram of the sheet member S1 that forms the protective layer 40. Both ends of the sheet member S1 have multiple notches N1 in a direction perpendicular to the direction in which the sheet member S1 is wrapped to form the protective layer 40. That is, both ends of the sheet member S1 have multiple notches N1 from the part facing the dome portion 14 toward the part facing the cylindrical portion 12. In this embodiment, the notches N1 are formed by notches so that the tips of the sheet member S1 on both sides of the notches N1 are adjacent to each other with a predetermined distance between them. Note that the notches N1 may be simple notches N1 that do not have notches. In this embodiment, the sheet member S1 has 10 notches N1.

Figure 3 is an explanatory diagram of the protective layer 40 in the dome portion 14. The protective layer 40 in the dome portion 14 has a plurality of overlapping portions 41 in which the sheet member S1 is arranged so that a portion of adjacent portions sandwiching each of the plurality of cuts N1 in the sheet member S1 overlaps with the sheet member S1. The hatched area in Figure 3 is the overlapping portion 41. In this embodiment, the overlapping portion 41 is formed by overlapping two sheets of the sheet member S1, and is arranged in the protective layer 40 at an equal angle centered on the central axis Ax of the liner 10. The protective layer 40 has 11 overlapping portions 41 in one dome portion 14. The overlapping portions 41 are provided so that there are no exposed portions of the reinforcing layer 30 where the protective layer 40 is not formed in the dome portion 14. Therefore, the overlapping portions 41 are smaller than the non-overlapping portions.

Figure 4 is an explanatory diagram of the protective layer 40 when viewed from the apex of the dome portion 14 in the outer circumferential direction. As shown in Figure 4, the overlapping portion 41 is thicker than the non-overlapping portion 41 of the protective layer 40 because two sheets of the sheet member S1 are overlapped.

5 is an explanatory diagram of the protective member 50. The protective member 50 has recesses 51 that can accommodate the overlapping portions 41 at positions facing each of the multiple overlapping portions 41, and has protrusions 52 at positions that do not face each of the multiple overlapping portions 41. That is, the protrusions 52 are located between the recesses 51, and the protrusions 52 are located on both sides of the recesses 51. The protrusions 52 are bonded to the portions of the protective layer 40 that are not the overlapping portions 41 by the adhesive layer 60. The protrusions 52 are bonded to the protective layer 40 by, for example, double-sided tape. The surface on which the protrusions 52 are bonded to the protective layer 40 is formed in a radial pattern so as to form a spherical inner surface. In this embodiment, the recesses 51 are arranged at equal intervals around the central axis Ax of the liner 10 in the protective member 50. The protective member 50 has 11 recesses 51. That is, the number of recesses 51 is the same as the number of overlapping portions 41. In this embodiment, each recess 51 accommodates an overlapping portion 41.

Figure 6 is a partial enlarged view of part A shown in Figure 5. In this embodiment, the protective member 50 has eleven components 53, each of which is a combination of a recess 51 and a protrusion 52 sandwiching the recess 51, arranged in a substantially circular shape. The recess 51 is recessed from the center of the protective member 50 toward the outer periphery. The protrusion 52 is formed to protrude from the outer periphery of the protective member 50 toward the center. The protrusion 52 is thinned in a direction perpendicular to the circumferential direction in which the protrusion 52 and the recess 51 are connected, so as to form a spherical inner surface.

The number of recesses 51 is determined, for example, by the outer diameter of the protective member 50, the strength of the material, and the thickness of the overlapping portion 41 that it contains, and is determined so that the protective performance against impact at the recesses 51 does not diverge from the protective performance against impact at the protrusions 52.

Figure 7 is a graph showing an example of the relationship between the diameter of the high-pressure tank 100 and the coefficient for determining the maximum number of recesses 51. The maximum number of recesses 51 is the number of recesses 51 for which the impact protection performance of the recesses 51 does not deviate from the impact protection performance of the protrusions 52. The horizontal axis shows the diameter of the cylindrical portion 12 of the high-pressure tank 100. The vertical axis shows the maximum coefficient, which indicates how many times the maximum number of recesses 51 is the number of overlapping portions 41. The larger the diameter of the high-pressure tank 100, the larger the maximum coefficient. In other words, the larger the diameter of the high-pressure tank 100, the larger the maximum number of recesses 51.

According to the high-pressure tank 100 of the present embodiment described above, the protective member 50 has a recess 51 that covers the overlapping portion 41 at a position opposite the overlapping portion 41, so that the protrusions 52 on both sides of the recess 51 in the circumferential direction contact the portion of the protective layer 40 that is not the overlapping portion 41. Therefore, it is possible to prevent the thickness of the overlapping portion 41 from reducing the attachment strength between the protective layer 40 and the protective member 50. In addition, since the overlapping portion 41 is smaller than the portion that is not the overlapping portion, the contact area between the protective member 50 and the protective layer 40 when the protrusions 52 are joined to the portion of the protective layer 40 that is not the overlapping portion 41 is larger than the contact area between the protective member 50 and the protective layer 40 when only the overlapping portion 41 is attached to the protective member 50. Therefore, the attachment strength of the protective member 50 to the protective layer 40 can be ensured.

The overlapping portions 41 are arranged at equal angular intervals, and the recesses 51 are arranged at equal angular intervals, and the number of recesses 51 is the same as the number of overlapping portions 41. Therefore, the recesses 51 can be easily positioned opposite the overlapping portions 41.

The protective member 50 is also fixed to the protective layer 40 by an adhesive layer 60. More specifically, it is fixed to the protective layer 40 by double-sided tape placed on the protrusions 52. Therefore, compared to when the protective member 50 is fixed to the protective layer 40 using an adhesive, there is no need to wait for the adhesive to harden, and the time required for the work can be reduced.

B. Other embodiments:
(B1) In the above-described embodiment, the overlapping portions 41 are disposed at equal angles, and the recesses 51 are disposed at equal angles. Alternatively, the overlapping portions 41 and the recesses 51 may be disposed at any angle. In this case, it is preferable that each overlapping portion 41 and each recess 51 are disposed at the same angle so that the recess 51 accommodates the overlapping portion 41.

(B2) In the above-described embodiment, the number of recesses 51 is the same as the number of overlapping portions 41. Not limited to this, the number of recesses 51 may be greater or less than the number of overlapping portions 41. When the number of recesses 51 is greater than the number of overlapping portions 41, the recesses 51 may be disposed in the portion of the protective layer 40 that is not the overlapping portion 41. That is, the protective member 50 has a recess 51 that does not accommodate an overlapping portion 41. Note that all overlapping portions 41 in the protective layer 40 are accommodated in the recess 51. When the number of recesses 51 is less than the number of overlapping portions 41, one recess 51 may be disposed to accommodate multiple overlapping portions 41. Note that the number of recesses 51 is preferably an integer multiple of the number of overlapping portions 41. This makes it easy to position the recess 51 in a position opposite the overlapping portion 41.

(B3) In the above-described embodiment, the overlapping portion 41 is formed by two overlapping sheet members S1. However, this is not limited to this, and the overlapping portion 41 may be formed by three or more overlapping sheet members S1.

(B4) In the above-described embodiment, the sheet member S1 is a single sheet-like member. Alternatively, the sheet member S1 may include multiple sheets having a substantially rectangular shape. In this case, the two ends of the sheet member S1 do not refer to the two ends of each sheet, but to the two ends of a sheet formed by integrating multiple sheets.

(B5) In the above-described embodiment, the protective layer 40 and the protective member 50 are attached by the adhesive layer 60, which is a double-sided tape. Alternatively, the protective member 50 may be attached to the protective layer 40 by an adhesive. The adhesive is, for example, a thermosetting resin.

The present disclosure is not limited to the above-described embodiments, and can be realized in various configurations without departing from the spirit of the present disclosure. For example, the technical features in the embodiments corresponding to the technical features in each form described in the Summary of the Invention column can be replaced or combined as appropriate to solve the above-described problems or to achieve some or all of the above-described effects. Furthermore, if a technical feature is not described as essential in this specification, it can be deleted as appropriate.

10...liner, 12...cylindrical part, 14...dome part, 20...mouthpiece, 30...reinforcing layer, 40...protective layer, 41...overlapped part, 50...protective member, 51...recess, 52...projection, 53...component, 60...adhesive layer, 100...high pressure tank, N1...notch, S1...sheet member

Claims (3)

A high-pressure tank,
a liner having a cylindrical portion and a hemispherical dome portion provided at each end of the cylindrical portion;
A reinforcing layer formed on a surface of the liner;
a protective layer formed on the liner including the cylindrical portion and the dome portion and provided on an outer periphery of the reinforcing layer, the protective layer being formed by wrapping a sheet-like sheet member in a circumferential direction of the cylindrical portion;
a protective member provided on an outer periphery of the protective layer in the dome portion,
the sheet member disposed on the liner has a plurality of cuts at both ends from the dome portion toward the cylindrical portion,
the protective layer in the dome portion has a plurality of overlapping portions in which the sheet members overlap each other by arranging the sheet members such that adjacent portions of the sheet members across the plurality of cuts partially overlap each other,
The protective member is
a recess capable of accommodating each of the overlapping portions at a position opposite to each of the overlapping portions;
A high-pressure tank having a convex portion at a position not facing any of the plurality of overlapping portions, the convex portion being joined to a portion of the protective layer that is not the overlapping portion. 2. The high-pressure tank according to claim 1,
The overlapping portions are disposed at equally spaced angles in the protective layer about a central axis of the liner,
The recesses are disposed at equal angular intervals around the central axis in the protective member,
A high-pressure tank, wherein the number of the recesses is an integer multiple of the number of the overlapping portions. The high-pressure tank according to claim 1 or 2, further comprising:
A high-pressure tank comprising an adhesive layer provided between the protective layer and the protective member, the adhesive layer fixing the protective member to the protective layer.

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