JP7776337B2 - Manufacturing method of the body section - Google Patents

Description

The present invention relates to a method for manufacturing a body section.

The pressure vessel disclosed in Patent Document 1 comprises a liner with gas barrier properties and an outer shell made of FRP that covers the outside of the liner. The liner is made of synthetic resin such as high-density polyethylene. The outer shell is made of fiber bundles containing carbon fiber and glass fiber.

Japanese Patent Application Laid-Open No. 2001-21099

The pressure vessel in Patent Document 1 has an outer shell formed by wrapping a fiber bundle around the outer peripheral surface of the liner using filament winding. Therefore, in order to ensure the rigidity of the liner, the liner is formed to a thickness greater than that required to ensure barrier properties. This has led to problems such as increased manufacturing costs for the pressure vessel.

The present invention was developed based on the above circumstances, and aims to provide a method for manufacturing a trunk section that can form a barrier layer of the desired shape and thickness.

The method for manufacturing a trunk section of the present invention comprises the steps of:
1. A method for manufacturing a body section segment that comprises a body base and a barrier layer covering an inner peripheral surface of the body base, the body section segment being combined with a dome section segment to form a pressure vessel, the method comprising:
a film member having barrier properties is wound around the outer periphery of a mandrel to form a cylindrical barrier layer;
a resin-impregnated fiber is wound around the barrier layer, and the resin is cured to form the body base, and the body base and the barrier layer are integrated together;
The body section is removed from the mandrel.

According to the present invention, a barrier layer is formed by wrapping a film material with barrier properties around the outer periphery of a mandrel to form a cylindrical shape. Therefore, by adjusting the width of the film material and the number of wraps around the mandrel, a barrier layer of the desired shape and thickness can be formed.

FIG. 1 is a side view showing a pressure vessel according to a first embodiment. FIG. 1 is a cross-sectional view of a pressure vessel. 3 is an enlarged cross-sectional view showing the vicinity of the boundary between the body section segment and the dome section segment in FIG. 2. FIG. 1A and 1B are explanatory diagrams illustrating the manufacturing process of the body section, where (A) is an explanatory diagram of the process of fixing one end of the film member to the mandrel, (B) is an explanatory diagram of the process of joining both ends of the film member, (C) is an explanatory diagram of the process of winding resin-impregnated fiber around the outer periphery of the first barrier layer, (D) is an explanatory diagram of the process of hardening the resin to form the body section, and (E) is an explanatory diagram of the process of pulling the body section from the mandrel. 10A and 10B are explanatory diagrams illustrating a part of the manufacturing process of the body section body of Example 2, where (A) is an explanatory diagram of the process of winding a film member around a mandrel, and (B) is an explanatory diagram of the process of joining both ends of the film member.

In the method for manufacturing a trunk section of the present invention, during the process of winding the film member around the mandrel, it is preferable to hold the film member at a predetermined position on the outer peripheral surface of the mandrel with a holding member while winding the film member around the outer peripheral surface and joining one end of the film member to the other end. It is preferable that the holding member holds the film member at a position closer to the other end than the one end. In this way, because the holding member holds the film member at a position closer to the other end than the one end, interference between the holding member and the other end of the film member can be prevented when joining the one end and the other end.

In the method for manufacturing a barrel segment of the present invention, the barrier layer is preferably formed by winding a sheet-like film member having a width dimension along the axis of the mandrel larger than that of the barrel base member around the outer periphery of the mandrel to form a cylindrical shape. In this way, by using a sheet-like film member having a width dimension along the axis of the mandrel larger than that of the barrel base member, the number of film member winding steps required to form a barrier layer of the same width can be reduced compared to when using a film member having a width dimension smaller than that of the barrel base member.

In the method for manufacturing a barrel section of the present invention, it is preferable that the barrier layer be formed by spirally winding a strip-shaped film member having a smaller width along the axis of the mandrel than the barrel base body around the outer periphery of the mandrel to form a cylindrical shape. In this way, by using a strip-shaped film member having a smaller width along the axis of the mandrel than the barrel base body, the width and diameter of the barrier layer can be changed by adjusting the number of wraps of the film member.

In the manufacturing method of the body segment of the present invention, it is preferable that the wrapping area of the barrier layer around the mandrel is larger than the wrapping area of the body base around the mandrel. This allows the barrier layer to protrude in the axial direction relative to the body base, covering the axial end face of the body base with the barrier layer.

In the method for manufacturing a barrel section of the present invention, the barrel base body is formed by heating and curing the resin, and it is preferable that the linear expansion coefficient of the barrier layer is greater than the linear expansion coefficient of the mandrel. This creates a gap between the mandrel and the barrier layer after the temperature drops after heating, making it easier for the barrier layer to separate from the mandrel and detach from the mandrel.

In the method for manufacturing a barrel segment of the present invention, the barrel base is formed by heating and curing the resin, and it is preferable that the linear expansion coefficient of the barrier layer is greater than the linear expansion coefficient of the barrel base. This makes it less likely that gaps will form between the barrier layer and the barrel base, thereby improving adhesion between the barrier layer and the barrel base.

Example 1
A first embodiment of the present invention will now be described with reference to FIGS. 1 to 4. FIG.

(Configuration of pressure vessel)
The pressure vessel 10 of this embodiment has a cylindrical capsule shape, as shown in Figure 1. The pressure vessel 10 is mounted on a vehicle, for example, and used as a container filled with high-pressure hydrogen gas. Note that the diameter, axial length, thickness of each layer, etc. of the pressure vessel 10 shown in Figures 1 to 4 are exaggerated, and the configurations shown in Figures 1 to 4 are merely examples.

As shown in Figure 2, the pressure vessel 10 comprises a body section 20, a dome section 30, and an external reinforcing layer 40. The pressure vessel 10 is constructed by combining the body section 20 and the dome section 30. The external reinforcing layer 40 surrounds the combined body section 20 and dome section 30. The pressure vessel 10 is provided with a nozzle 11 as shown in Figure 1. Note that Figure 2 shows the pressure vessel 10 before the nozzle 11 is attached. The pressure vessel 10 has barrier properties. In this Example 1, barrier properties are defined as the ability to prevent or inhibit a fluid (such as hydrogen gas) filled inside the pressure vessel 10 from permeating the pressure vessel 10 and leaking to the outside of the pressure vessel 10.

As shown in FIG. 2, the trunk segment 20 comprises a trunk base 50 and a first barrier layer 60. The trunk base 50 is cylindrical and elongated in the axial direction (along the axis L). The inner diameter of the trunk base 50 is constant throughout its entire length. The outer diameter of the trunk base 50 is constant throughout its entire length, excluding the recess 51 described below. The trunk base 50 is made of fiber-reinforced resin, such as carbon fiber reinforced plastic (CFRP) or glass fiber reinforced plastic (GFRP). The trunk base 50 is formed, for example, by hoop-winding fiber bundles (not shown) impregnated with liquid thermosetting resin, or fiber bundles impregnated with thermosetting resin and brought to a semi-cured state (prepreg fiber) using, for example, a filament winding method. The fiber bundles are made of filament-like fibers, such as carbon fiber, glass fiber, or Kepler fiber, which are bundled together.

As shown in Figure 3, recesses 51 are provided on both axial ends of the outer peripheral surface of the barrel base body 50. The recesses 51 are provided around the entire circumference of the axis. The portion of the barrel base body 50 where the recesses 51 are provided is thinner than the remaining portion of the barrel base body 50 (the portion toward the center of the axial direction). The outer dimensions of the recesses 51 decrease axially outward. The recesses 51 comprise a first tapered portion 51A and a second tapered portion 51B. The first tapered portion 51A and the second tapered portion 51B form a two-stage slope. The slope angle of the first tapered portion 51A is greater than the slope angle of the second tapered portion 51B.

As shown in FIG. 2, the first barrier layer 60 is provided to cover the inner peripheral surface of the body base body 50. The first barrier layer 60 corresponds to an example of the "barrier layer" in this disclosure. The first barrier layer 60 has barrier properties. Materials used for the first barrier layer 60 include, for example, EVOH (ethylene-vinyl alcohol copolymer) and PA6 (nylon 6). The first barrier layer 60 is used to block or prevent fluid stored within the pressure vessel 10 from permeating to the outside.

As shown in FIG. 3, the first barrier layer 60 covers both axial ends of the barrel base body 50. The axial ends of the first barrier layer 60, which extend from both axial ends of the barrel base body 50, are folded back to cover both axial ends of the outer peripheral surface of the barrel base body 50. Specifically, the first barrier layer 60 covers the recess 51 (first tapered portion 51A, second tapered portion 51B), the first end face 52A, and the second end face 52B. The first end face 52A is the axial end face of the barrel base body 50. The second end face 52B is the end face that continues toward the axial center from the second tapered portion 51B.

As shown in FIG. 2, the dome section segment 30 includes a dome section base 31 and a second barrier layer 32. The dome section base 31 is a hemispherical portion connected to the longitudinal end of the body section base 50. The diameter of the dome section base 31 decreases as it moves away from the body section base 50. The thickness of the dome section base 31 is smaller than the thickness of the body section base 50 (excluding the recess 51). The dome section base 31 is made of fiber-reinforced resin, such as carbon fiber reinforced plastic (CFRP) or glass fiber reinforced plastic (GFRP). The dome section base 31 is formed by, for example, laminating fiber bundles (not shown) impregnated with liquid thermosetting resin, or fiber bundles impregnated with thermosetting resin in a semi-cured state (prepreg fiber), using a hand layup method, for example, to form a spherical shell-shaped molded product, which is then divided in half. The fiber bundle is made of thread-like fibers such as carbon fiber, glass fiber, and Kepler fiber. As shown in Figure 1, a nozzle 11 is provided at the top of the dome section segment 30.

As shown in FIG. 2, the second barrier layer 32 is provided to cover the inner peripheral surface of the dome base 31. The second barrier layer 32 has the same configuration as the first barrier layer 60. The end of the second barrier layer 32 on the trunk section 20 side covers the end surface 31A of the dome base 31.

As shown in FIG. 3 , the end of the body section 20 is inserted inside the end of the dome section 30, and the body section 20 and dome section 30 are joined together. The first barrier layer 60 covering the end of the body section 20 (more specifically, the first tapered portion 51A, the second tapered portion 51B, and the second end surface 52B) comes into contact with the second barrier layer 32 covering the end of the dome section 30. The contacting first barrier layer 60 and second barrier layer 32 are crushed by the end of the body section 20 and the end of the dome section 30, generating a repulsive force (restoring force), ensuring sealing at the boundary between the body base 50 and the dome base 31.

The external reinforcing layer 40 is made of fiber-reinforced resin, such as carbon fiber reinforced plastic (CFRP) or glass fiber reinforced plastic (GFRP). The external reinforcing layer 40 is formed to cover the entire outer periphery of the body section segment 20 and the entire outer periphery of the dome section segment 30. The external reinforcing layer 40 is formed by helical winding, for example, using a filament winding method. The external reinforcing layer 40 is formed by winding, for example, fiber bundles (not shown) impregnated with liquid thermosetting resin, or fiber bundles impregnated with thermosetting resin in a semi-cured state (prepreg fiber), around the outer surfaces of the body section segment 20 and the dome section segment 30, which rotate around the axis L (see Figure 2). The fiber bundles are made of bundles of thread-like fibers, such as carbon fiber, glass fiber, or Kepler fiber.

(Method for manufacturing trunk section segments)
Next, a manufacturing method for the body section 20 will be described. First, as shown in Fig. 4(A), one end 71 of a film member 70 having barrier properties is fixed to the outer peripheral surface of a cylindrical mandrel 80. Examples of materials that can be used for the film member 70 include EVOH (ethylene-vinyl alcohol copolymer) and PA6 (nylon 6). The film member 70 is in a sheet form. Examples of materials that can be used for the mandrel 80 include metals (aluminum, iron, etc.).

The width dimension of the film member 70 (the width dimension in the direction along the axis 81 of the mandrel 80) is set to be larger than the width dimension of the body base 50 (the width dimension in the direction along the axis 81 of the mandrel 80) that will be formed in a later process. In other words, the winding area of the first barrier layer 60 around the mandrel 80 is set to be larger than the winding area of the body base 50 around the mandrel 80.

As shown in FIG. 4A , one end 71 of the film member 70 is held by a holding member 90 at a predetermined position on the outer circumferential surface of the mandrel 80. The one end 71 of the film member 70 is positioned parallel to the axis 81 of the mandrel 80. The holding member 90 is made of, for example, a metal material. The holding member 90 is configured in a block shape. The surface of the holding member 90 that contacts the film member 70 (pressing surface) may be flat or curved to correspond to the outer circumferential surface of the film member 70. The one end 71 of the film member 70 is clamped between the outer circumferential surface of the mandrel 80 and the pressing surface of the holding member 90. The holding member 90 holds the film member 70 at a position closer to the other end 72 than the one end 71 (e.g., a position several millimeters closer to the other end 72). This prevents interference between the holding member 90 and the other end 72 when joining the two ends 71, 72 of the film member 70.

Next, as shown in FIG. 4(B), the other end 72 of the film member 70 is wound cylindrically around the outer periphery of the mandrel 80, and the other end 72 is joined to the one end 71. The two ends 71, 72 of the film member 70 are joined, for example, by applying pressure and heat using a holding member 90. This forms a cylindrical first barrier layer 60. In this way, the first barrier layer 60 is formed by winding the film member 70 as a base using the mandrel 80. Therefore, by adjusting the width of the film member 70 and the number of turns around the mandrel 80, it is possible to form a first barrier layer 60 with the desired shape and thickness. Furthermore, by using a sheet-like film member 70 as a base, it is possible to form the first barrier layer 60 using a smaller number of turns of the film member 70, thereby reducing the amount of film member 70 used.

Next, as shown in FIG. 4(C), resin-impregnated fiber 55 is wound around the outer peripheral surface of the first barrier layer 60. The resin-impregnated fiber 55 may be, for example, a fiber bundle (such as a bundle of carbon fibers) impregnated with a liquid thermosetting resin (such as an epoxy resin), or a fiber bundle impregnated with a thermosetting resin that has been semi-cured (prepreg fiber). The resin-impregnated fiber 55 is wound around the first barrier layer 60 using a filament winding method. The winding area of the trunk base body 50 around the mandrel 80 is set smaller than the winding area of the first barrier layer 60 around the mandrel 80. When winding the resin-impregnated fiber 55, the thickness of the bundle of resin-impregnated fiber 55 at both axial ends may be reduced so that the aforementioned recesses 51 are formed. The recesses 51 may be formed by cutting or other methods after the trunk segment 20 is formed, with the winding thickness of the resin-impregnated fiber 55 kept uniform in the axial direction.

Next, the resin contained in the resin-impregnated fibers 55 is cured. For example, the resin contained in the resin-impregnated fibers 55 is cured by heating at 150°C for 40 minutes. This results in the formation of a cylindrical barrel base body 50, as shown in Figure 4(D). Both axial ends 60A of the first barrier layer 60 protrude outward beyond both axial ends of the barrel base body 50. By making the first barrier layer 60 protrude in the axial direction relative to the barrel base body 50, the first barrier layer 60 can cover the axial end faces of the barrel base body 50 (more specifically, the recess 51, first end face 52A, and second end face 52B shown in Figure 3). Heating brings the barrel base body 50 and the first barrier layer 60 into close contact, forming a barrel segment 20 in which the barrel base body 50 and the first barrier layer 60 are integrated.

The linear expansion coefficient of the first barrier layer 60 is set to be greater than the linear expansion coefficient of the mandrel 80. For example, the first barrier layer 60 is made of EVOH (ethylene-vinyl alcohol copolymer), and the mandrel 80 is made of aluminum. Therefore, after the temperature drops after heating, the first barrier layer 60 easily separates from the mandrel 80, easily creating a gap between the mandrel 80 and the first barrier layer 60, making it easier to separate the first barrier layer 60 from the mandrel 80 in a subsequent process.

In addition, the linear expansion coefficient of the first barrier layer 60 is set to be greater than the linear expansion coefficient of the barrel base 50. This makes it less likely for gaps to form between the first barrier layer 60 and the barrel base 50, thereby improving adhesion between the first barrier layer 60 and the barrel base 50.

Next, as shown in Figure 4(E), the body section 20 is removed from the mandrel 80. When the body section 20 is removed, the body section 20 may be at a temperature of approximately 50°C due to residual heat from the heating process during resin curing.

(Effects of this embodiment)
The effects of the first embodiment will be described below. In the manufacturing method of the body section of the first embodiment, the first barrier layer 60 is formed by winding a film member 70 having barrier properties around the outer periphery of a mandrel 80 to form a cylindrical shape. Therefore, by adjusting the width dimension of the film member 70 and the number of windings around the mandrel 80, the first barrier layer 60 can be formed with a desired shape and thickness. This eliminates the need for a mold for forming the barrier layer, thereby reducing the manufacturing cost of the body section 20. Furthermore, in conventional methods, the barrier layer is wound around the mandrel using a filament winding method, with resin-impregnated fibers wound around the mandrel. This requires the barrier layer to be thicker than necessary to ensure its barrier properties in order to ensure its rigidity. In contrast, in the manufacturing method of the body section of the first embodiment, the first barrier layer 60 does not need to function as a mandrel, and the first barrier layer 60 can be made thinner, thereby reducing the manufacturing cost.

In the manufacturing method of the body section in this Example 1, the holding member 90 holds the film member 70 in a position closer to the other end 72 than the one end 71, thereby preventing interference between the holding member 90 and the other end 72 when joining the one end 71 and the other end 72 of the film member 70.

The manufacturing method of the barrel section in this Example 1 involves winding a sheet-like film member 70, which has a width dimension along the axis 81 of the mandrel 80 larger than that of the barrel base body 50, around the outer periphery of the mandrel 80 to form a cylindrical shape, to form the first barrier layer 60. In this way, by using a sheet-like film member 70 whose width dimension along the axis 81 of the mandrel 80 is larger than that of the barrel base body 50, the number of winding steps for the film member 70 can be reduced when forming a first barrier layer 60 of the same width dimension, compared to when using a film member 70 whose width dimension is smaller than that of the barrel base body 50.

In the manufacturing method of the barrel section in this Example 1, the wrapping area of the first barrier layer 60 around the mandrel 80 is larger than the wrapping area of the barrel base body 50 around the mandrel 80. This allows the first barrier layer 60 to protrude in the axial direction relative to the barrel base body 50, and the first barrier layer 60 can cover up to the first axial end surface 52A of the barrel base body 50.

The method for manufacturing the trunk section in this Example 1 forms the trunk base body 50 by heating and curing the resin. The linear expansion coefficient of the first barrier layer 60 is greater than the linear expansion coefficient of the mandrel 80. As a result, after the temperature drops after heating, a gap forms between the mandrel 80 and the first barrier layer 60, making it easier for the first barrier layer 60 to separate from the mandrel 80, and thus the first barrier layer 60 to be easily detached from the mandrel 80.

The manufacturing method for the barrel section in this Example 1 forms the barrel base 50 by heating and curing the resin, and the linear expansion coefficient of the first barrier layer 60 is greater than the linear expansion coefficient of the barrel base 50. This makes it less likely that gaps will form between the first barrier layer 60 and the barrel base 50, thereby improving adhesion between the first barrier layer 60 and the barrel base 50.

Example 2
A second embodiment of the present invention will be described below with reference to Fig. 5. The method for manufacturing the trunk section in the second embodiment differs from that in the first embodiment in the way the film member is wrapped around it, but the other configurations are the same as those in the first embodiment. Therefore, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

In the manufacturing method of the body section 20 of Example 2, a strip-shaped film member 270 with barrier properties, as shown in Figure 5, is used. The material of the film member 270 is the same as that of the film member 70, and examples of such materials include EVOH (ethylene-vinyl alcohol copolymer) and PA6 (nylon 6).

The width dimension of the film member 270 (the width dimension in the direction along the axis 81 of the mandrel 80) is set to be smaller than the width dimension of the body base 50 (the width dimension in the direction along the axis 81 of the mandrel 80) that will be formed in a later process. The wrapping area of the first barrier layer 260 around the mandrel 80 is set to be larger than the wrapping area of the body base 50 around the mandrel 80.

As shown in Figure 5(A), one end of the film member 270 is fixed at a predetermined position on the outer periphery of the mandrel 80, while the other end of the film member 270 is spirally wrapped around the outer periphery of the mandrel 80 to form a cylindrical shape.

Next, as shown in FIG. 5(B), the other end of the film member 270 is joined to another location to form the first barrier layer 260. In this way, by using a strip-shaped film member 270 whose width along the axis 81 of the mandrel 80 is smaller than that of the barrel base body 50, the width and diameter of the first barrier layer 60 can be changed by adjusting the number of wraps of the film member 270. Therefore, by adjusting the number of wraps of the film member 70 around the mandrel 80, it is possible to form a first barrier layer 60 of the desired shape and thickness.

The processes of winding the resin-impregnated fiber 55, curing the resin, and pulling the body segment 20 from the mandrel 80 are the same as in Example 1.

<Other Examples>
The present invention is not limited to the embodiments described above and illustrated in the drawings, and the following embodiments, for example, are also included within the technical scope of the present invention.
(1) In the first and second embodiments, the mandrel 80 is cylindrical. However, it may have other shapes (such as a cylindrical shape with an elliptical cross section).
(2) In the first and second embodiments, the two end portions 71 and 72 of the film member 70 are joined by applying pressure and heat, but ultrasonic welding or the like may also be used.

DESCRIPTION OF SYMBOLS 10... Pressure vessel 11... Nozzle 20... Body section segment 30... Dome section segment 31... Dome section base 31A... End surface 32... Second barrier layer 40... External reinforcing layer 50... Body section base 51... Recess 51A... First tapered section 51B... Second tapered section 52A... First end surface 52B... Second end surface 55... Resin-impregnated fiber 60... First barrier layer (barrier layer)
60A... end 70... film member 71... one end portion 72... other end portion 80... mandrel 81... shaft 90... holding member 260... first barrier layer 270... film member L... axis line of body segment

Claims (7)

1. A method for manufacturing a body section segment that comprises a body base and a barrier layer covering an inner peripheral surface of the body base, the body section segment constituting a pressure vessel when combined with a dome section segment, comprising:
a film member having barrier properties is wound around the outer periphery of a mandrel to form a cylindrical barrier layer;
a resin-impregnated fiber is wound around the barrier layer, and the resin is cured to form the trunk base body, and the trunk base body and the barrier layer are integrated together;
The body section is removed from the mandrel .
In the process of winding the film member around the mandrel, the film member is held at a predetermined position on the outer peripheral surface of the mandrel by a holding member, while the film member is wound around the outer peripheral surface and one end of the film member is joined to the other end of the film member;
The holding member holds the film member at a position closer to the other end than the one end . 1. A method for manufacturing a body section segment that comprises a body base and a barrier layer covering an inner peripheral surface of the body base, the body section segment being combined with a dome section segment to form a pressure vessel, the method comprising:
a film member having barrier properties is wound around the outer periphery of a mandrel to form a cylindrical barrier layer;
a resin-impregnated fiber is wound around the barrier layer so that a winding area of the barrier layer around the mandrel is larger than a winding area of the barrel base around the mandrel, and the resin is cured to form the barrel base and integrate the barrel base and the barrier layer;
the axial ends of the barrier layer that extend from both axial ends of the barrel base body are folded back to cover both axial ends of the outer peripheral surface of the barrel base body;
The method for manufacturing a body section includes separating the body section from the mandrel. A method for manufacturing a body segment according to claim 1 or 2, wherein the barrier layer is formed by wrapping the sheet-like film member, which has a width dimension along the axis of the mandrel greater than that of the body base body, around the outer periphery of the mandrel to form a cylindrical shape. 3. The method for manufacturing a barrel section body according to claim 2, wherein the barrier layer is formed by spirally winding the strip-shaped film member, which has a width dimension along the axis of the mandrel smaller than that of the barrel base body, around the outer periphery of the mandrel to form a cylindrical shape. The method for manufacturing a body section according to claim 1 or claim 3 which relies on claim 1, wherein the winding area of the barrier layer around the mandrel is larger than the winding area of the body base body around the mandrel. forming the body base by heating and curing the resin;
The method for manufacturing a body section according to any one of claims 1 to 5, wherein the barrier layer has a linear expansion coefficient greater than a linear expansion coefficient of the mandrel. forming the body base by heating and curing the resin;
The method for manufacturing a body section according to any one of claims 1 to 6, wherein the barrier layer has a linear expansion coefficient greater than a linear expansion coefficient of the body base body.