High pressure tank manufacturing method

Abstract

The present invention provides a method for manufacturing a high-pressure tank. The high-pressure tank manufacturing device comprises: a mold having a cavity in which an intermediate body is arranged, the intermediate body having a fiber bundle wound on an inner liner; and a pin portion arranged in a manner movable relative to the mold and moving between a contact position and a separation position, the contact position being a position where the pin portion protrudes from the surface of the cavity into the cavity and contacts the intermediate body arranged in the cavity, and the separation position being a position where the pin portion is separated from the intermediate body arranged in the cavity, the pin portion being arranged so that, at the contact position, molten resin flowing into the cavity can flow over the pin portion between the surface of the cavity and the intermediate body.

Description

Technical Field

[0001] This specification discloses a high-pressure tank manufacturing device and a high-pressure tank manufacturing method. Background Art

[0002] Japanese Patent Application Laid-Open No. 2019-142118 discloses a method for manufacturing a high-pressure tank. In this manufacturing method, a sliding core arranged so as to surround the resin injection port of the mold is moved from the mold cavity surface of the mold toward the intermediate body, so that the sliding core abuts against the fiber bundle, and resin is injected from the resin injection port to impregnate the fiber bundle. When the resin is injected, the sliding core abuts against the surface of the intermediate body, so that the resin flows forcibly toward the inner layer side of the fiber bundle, and the resin is impregnated into the inner layer of the fiber bundle.

[0003] The shape of the high-pressure tank is determined by the area where the high-pressure tank is mounted. The intermediate of the high-pressure tank is made by winding a fiber bundle on the liner. The shape of the intermediate is formed to match the shape of the high-pressure tank. For example, in the case where the high-pressure tank is slender, the intermediate is also formed in a slender shape. Depending on the shape of the intermediate, it may be deformed before being impregnated with resin, and the intermediate may contact the surface of the mold cavity over a wide range.

[0004] In the area of ​​the surface of the intermediate body that contacts the surface of the cavity, the molten resin does not flow into the space between the intermediate body and the cavity. As a result, the molten resin does not contact the surface of the intermediate body, and the molten resin cannot be impregnated from the surface of the intermediate body. As a result, there may be a portion in the fiber bundle that is not fully impregnated with the resin. Summary of the invention

[0005] In the present specification, a technology for suppressing the contact between the intermediate and the surface of the cavity is provided. In the present specification, a high-pressure tank manufacturing device is disclosed. The high-pressure tank manufacturing device comprises: a mold having a cavity in which an intermediate is arranged, and the intermediate has a fiber bundle wound on an inner lining; and a pin portion, which is arranged in a manner movable relative to the mold and moves between a contact position and a separation position, the contact position being a position where the pin portion protrudes from the surface of the cavity into the cavity and contacts the intermediate arranged in the cavity, and the separation position being a position where the pin portion is separated from the intermediate arranged in the cavity, and the pin portion is arranged so that, at the contact position, the molten resin flowing into the cavity can flow over the pin portion between the surface of the cavity and the intermediate.

[0006] In addition, the present specification discloses a method for manufacturing a high-pressure tank. The method includes: a configuration step of configuring an intermediate body in a cavity of the above-mentioned high-pressure tank manufacturing device, and configuring a pin portion at a contact position, wherein the intermediate body has a fiber bundle wound on an inner liner; a filling step of injecting molten resin into the cavity, causing the molten resin to flow between the surface of the cavity and the intermediate body over the pin portion, thereby filling the cavity with the molten resin; an impregnation step of impregnating the fiber bundle with the resin in the cavity; and a moving step of moving the pin portion from the contact position to the separation position.

[0007] Effects of the Invention

[0008] According to the above structure, in the cavity, the contact between the intermediate body and the cavity surface can be suppressed by the contact between the pin and the intermediate body. The molten resin can flow between the cavity surface and the intermediate body over the pin, so that the flow of the molten resin can be suppressed from being blocked by the pin. In addition, by moving the pin from the contact position to the separation position, the molten resin can also contact the surface of the intermediate body in the portion in contact with the pin. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Features, advantages, and technical and industrial significance of exemplary embodiments of the present invention are described below with reference to the accompanying drawings, in which like reference numerals represent like elements.

[0010] Figure 1 It is a longitudinal sectional view of the high pressure tank manufacturing apparatus of the embodiment.

[0011] Figure 2 It is a longitudinal sectional view of the high-pressure tank of the embodiment.

[0012] Figure 3 This is a schematic diagram showing the flow of the resin flowing in the cavity of the example.

[0013] Figure 4 This is a flowchart showing a method for manufacturing a high-pressure tank according to an embodiment.

[0014] Figure 5 It is a longitudinal sectional view of the high-pressure tank manufacturing apparatus in a state where the pin portion of the embodiment is located at a separated position. DETAILED DESCRIPTION

[0015] The technical elements of the high-pressure tank manufacturing apparatus disclosed in this specification are listed below. In addition, each of the following technical elements is useful independently.

[0016] The pin portion may include a plurality of pins that protrude from the surface of the cavity in the same direction and are arranged to be separated from each other.

[0017] According to this structure, the intermediate body can be supported by the plurality of pins protruding in the same direction contacting the intermediate body at a plurality of positions. Thus, the intermediate body can be prevented from contacting the cavity surface.

[0018] The intermediate body may include: a cylindrical central portion extending in the longitudinal direction of the intermediate body; and front end portions at both ends of the central portion that are gradually tapered toward the front end, and the pin portion may be in contact with the central portion.

[0019] Since the front end of the intermediate body has a tapered shape, it is difficult to deform. On the other hand, the central part of the intermediate body has a cylindrical shape and is easy to deform. By the pin portion contacting the central part, the pin portion can be brought into contact with the central part which is more easily deformed.

[0020] In the moving step of the method for manufacturing a high-pressure tank, the pin portion may be moved from the contact position to the separated position before the resin is solidified in the cavity.

[0021] According to this structure, the uncured molten resin can flow into the space formed by the pin portion moving from the contact position to the separation position. As a result, the resin can also contact the portion of the surface of the intermediate body that contacts the pin portion. As a result, the resin can be impregnated into the fiber bundle from the surface of the intermediate body over the entire area of ​​the intermediate body.

[0022] (Example)

[0023] like Figure 1 As shown, the high pressure tank manufacturing device 10 of this embodiment is used to manufacture a high pressure tank 100 (refer to Figure 2 ) is used when

[0024] (Structure of high pressure tank)

[0025] First, refer to Figure 2 The high-pressure tank 100 is described. The high-pressure tank 100 is mounted on a fuel cell vehicle and stores fuel gas such as natural gas and hydrogen. The high-pressure tank 100 includes a liner 102, a fiber bundle 104 impregnated with a resin, and an annular member 106. The liner 102 is made of a gas-barrier resin material. The liner 102 has a cylindrical shape at a central portion 102a. The front end portion 102b of the liner 102 gradually tapers as it separates from the central portion 102a and moves toward the end of the liner 102.

[0026] A fiber bundle 104 is arranged on the outer surface of the liner 102. The fiber bundle 104 is formed by winding carbon fibers on the outer surface of the liner 102. The fiber bundle 104 is arranged over the entire length of the liner 102. The fiber bundle 104 is formed by winding carbon fibers by a braiding method.

[0027] The fiber bundle 104 is held by the liner 102 and the annular member 106 at both ends of the high-pressure tank 100. The high-pressure tank manufacturing device 10 is used to impregnate the fiber bundle 104 of the intermediate 200 in which the fiber bundle 104 is wound around the liner 102 and the fiber bundle 104 is held by the annular member 106. Therefore, the high-pressure tank manufacturing device 10 can also be called an impregnation device 10. In addition, in a modified example, the use of the high-pressure tank 100 is not limited to a tank for storing fuel gas of a fuel cell vehicle, and it can also be a tank having the same structure as above and storing high-pressure gas.

[0028] (Structure of high pressure tank manufacturing apparatus)

[0029] like Figure 1 As shown, the mold 11 and the pin portion 20 are provided. The mold 11 includes an upper mold 12 and a lower mold 14. When the upper mold 12 and the lower mold 14 are closed, a cavity 40 is formed in the mold 11. The intermediate body 200 is arranged in the cavity 40. The cavity 40 has a space slightly larger than the outer shape of the intermediate body 200. Therefore, when the intermediate body 200 is arranged in the cavity 40, a small gap is formed between the cavity 40 and the intermediate body 200 to allow the molten resin to flow. In addition, Figure 1 and Figure 5 In the figure, the ease of viewing is prioritized, and the gap between the cavity 40 and the intermediate body 200 is depicted in a larger size.

[0030] The pin unit 20 is mounted on the upper mold 12. The pin unit 20 includes a plurality of pins 22, a support plate 24, and an actuator 26. The plurality of pins 22 each have a cylindrical shape. The plurality of pins 22 are arranged in an arrangement hole 42 extending upward from the surface of the cavity 40 in the upper mold 12. Figure 1 and Figure 5 In the figure, the gap between the pin 22 and the arrangement hole 42 is drawn relatively large, but a gap is provided between the pin 22 and the arrangement hole 42 to such an extent that the molten resin does not flow in.

[0031] A plurality of pins 22 are formed in the upper mold 12 in the length direction (i.e. Figure 1 The plurality of pins 22 are arranged in parallel with each other. The plurality of pins 22 are mounted on a support plate 24 at the upper end. The support plate 24 is configured to be movable in the vertical direction relative to the upper mold 12 by an actuator 26. The actuator 26 may be a hydraulic cylinder, an air cylinder, a servo motor, etc. By using the actuator 26 to move the support plate 24 in the vertical direction, the plurality of pins 22 are configured to be movable in the vertical direction relative to the upper mold 12. Figure 1 The contact position shown with the intermediate body 200 is Figure 5 The pins 22 move in the vertical direction between the separation positions from the intermediate body 200 shown. When the pins 22 are arranged at the separation positions, the lower end surfaces of the pins 22 are located on the same plane as the surface of the cavity 40.

[0032] The pin unit 30 is mounted on the lower mold 14. The pin unit 30 includes a plurality of pins 32, a support plate 34, and an actuator 36. The plurality of pins 32 each have the same structure as the plurality of pins 22. The plurality of pins 32 are arranged in a placement hole 44 extending downward from the surface of the cavity 40 in the lower mold 14. The relationship between the pin 32 and the placement hole 44 is the same as the relationship between the pin 22 and the placement hole 42.

[0033] The plurality of pins 32 are provided with a support plate 34 similar to the support plate 24 at their lower ends. The support plate 34 is configured to be movable in the vertical direction relative to the lower mold 14 by an actuator 36 similar to the actuator 26. Thus, the plurality of pins 32 are configured to be movable in the vertical direction relative to the lower mold 14 by using the actuator 36 to move the support plate 34 in the vertical direction. Figure 1 The contact position of the intermediate body 200 shown is similar to Figure 5 The pins 32 move in the vertical direction between the separated positions from the intermediate body 200 shown. When the pins 32 are arranged at the separated positions, the lower end surfaces of the pins 32 are located on the same plane as the surface of the cavity 40.

[0034] like Figure 3 As shown, the lower mold 14 is provided with support parts 16 and 18 for supporting both ends of the intermediate body 200. The support parts 16 and 18 support the annular member 106 of the intermediate body 200. Thus, the intermediate body 200 is supported in the mold 11. In addition, the lower mold 14 is provided with a plurality of flow paths 46 for filling the cavity 40 with resin. The plurality of flow paths 46 have a groove shape for guiding the molten resin injected from the outside of the mold 11 into the mold 11 into the cavity 40.

[0035] (Method for manufacturing high pressure tank)

[0036] Next, the manufacturing method of the high-pressure tank 100 is described. In the high-pressure tank 100, first, the fiber bundle 104 is arranged on the liner 102 and held by the annular member 106, thereby manufacturing the intermediate body 200. The intermediate body 200 has a central part 200a formed by the central part 102a of the liner 102 and a front end part 200b formed by the front end part 102b of the liner 102. The central part 200a has a cylindrical shape. The front end part 200b is separated from the central part 200a and gradually becomes thinner toward the front end of the intermediate body 200.

[0037] Next, a resin impregnation process is performed to impregnate the fiber bundle 104 with resin. In the resin impregnation process, Figure 1As shown, in a mold 11 equipped with a device 300 (such as a punching device), resin is injected into a cavity 40 in which an intermediate body 200 is arranged, and pressurized, thereby performing so-called RTM (abbreviation of Resin Transfer Molding) molding in which the fiber bundle 104 is impregnated with resin.

[0038] like Figure 4 As shown, in the resin impregnation process, first, the upper mold 12 and the lower mold 14 of the mold 11 are separated, and the intermediate 200 is arranged in the shape part of the cavity 40 of the lower mold 14, and the intermediate 200 is fixed by the support parts 16 and 18 (S12). Then, the upper mold 12 and the lower mold 14 are closed. In the process of arranging the intermediate 200 in the mold 11, the plurality of pins 22 and 32 are arranged at the contact position before the intermediate 200 is arranged. In addition, in a modified example, the plurality of pins 22 and 32 can also be arranged at the separation position when the intermediate 200 is arranged in the mold 11, and move to the contact position after the intermediate 200 is arranged in the mold 11. The plurality of pins 22 and 32 are arranged at a position in contact with the central part 200a of the intermediate 200De, and on the other hand, they are not arranged at a position corresponding to the front end part 200b.

[0039] Next, molten resin is injected into the mold cavity 40 (S14). The injected resin is, for example, epoxy resin. When the resin is filled into the mold cavity 40, the resin in the mold cavity 40 is pressurized to a predetermined pressure (S16). Next, when the resin in the mold cavity 40 is pressurized to a predetermined pressure, the predetermined pressure is maintained for a predetermined period (S18). Thus, the resin is impregnated into the fiber bundle 104.

[0040] As the resin is impregnated while being maintained under pressure, the resin gradually solidifies. In S20, before the resin is completely solidified, the plurality of pins 22 and 32 are moved from the contact position to the separation position. As a result, the resin before solidification flows into the space formed by the movement of the plurality of pins 22 and 32. Thus, the resin can be impregnated from the position where the plurality of pins 22 and 32 are in contact.

[0041] Next, after the resin is cured ( S20 ), the upper mold 12 and the lower mold 14 are separated, and the molded high-pressure tank 100 is taken out of the mold 11 ( S22 ), thereby completing the resin impregnation process.

[0042] (Effect)

[0043] The intermediate body 200 is sometimes produced in a deformed state relative to the design value due to the deformation of the resin liner 102. At the stage where the intermediate body 200 is arranged in the mold 11, the intermediate body 200 is supported by the support parts 16 and 18. When the intermediate body 200 is not deformed, a certain gap is formed between the surface of the cavity 40 and the intermediate body 200 to allow the molten resin to flow in. However, since the intermediate body 200 is actually deformed, the central part 200a of the intermediate body 200 will bend when the two ends are supported by the support parts 16 and 18. In addition, in order to avoid contact between the intermediate body 200 and the surface of the cavity 40, if the gap between the intermediate body 200 and the surface of the cavity 40 is increased, the amount of resin required for impregnation increases.

[0044] In the high pressure tank manufacturing device 10, pins 20 and 30 are arranged to protrude toward the cavity 40. According to this structure, the pins 20 and 30 can support the bent intermediate body 200 in a manner that does not contact the surface of the cavity 40. Thus, the gap between the intermediate body 200 and the surface of the cavity 40 is maintained. As a result, Figure 3 As shown, the molten resin flowing into the cavity 40 from the flow path 46 flows between the intermediate body 200 and the cavity 40 and spreads over the entire surface of the intermediate body 200 .

[0045] The plurality of pins 22 and 32 are arranged separately from the flow path 46. In addition, the plurality of pins 22 and 32 are arranged separately from each other in the cavity 40. Therefore, the molten resin flowing between the intermediate 200 and the cavity 40 will not be blocked by the plurality of pins 22 and 32, and can flow over the plurality of pins 22 and 32. Thus, it is possible to avoid a situation where the flow of the molten resin is obstructed by the plurality of pins 22 and 32. In addition, in a modified example, the flow path for injecting the molten resin into the cavity 40 is not limited to the flow path 46. For example, the flow path may also be arranged above the cavity 40 in the upper mold 12. In addition, there is no limit to the number of flow paths. Regardless of the type of flow path, the pin portions 20 and 30 do not have a configuration or shape that obstructs the flow of the molten resin flowing in the cavity 40.

[0046] In addition, the plurality of pins 22 protrude from the surface of the cavity 40 in the same direction (i.e., downward direction). According to this structure, the plurality of pins 22 can suppress deformation of the intermediate body 200. Thus, it is possible to suppress the intermediate body 200 from bending in the direction in which the plurality of pins 22 protrude and contacting the surface of the cavity 40. The same applies to the plurality of pins 32.

[0047] The plurality of pins 22 and 32 move from the contact position to the separated position before the molten resin solidifies, thereby allowing the resin to be impregnated even from the contact position of the plurality of pins 22 and 32. This can prevent the occurrence of a portion that is not properly impregnated with the resin.

[0048] A plurality of pins 22 and 32 are arranged in the central portion 200a of the intermediate body 200, and on the other hand, are not arranged in the front end portion 200b of the intermediate body 200. In the liner 102, deformation is easy to occur in the cylindrical central portion 102a, and on the other hand, deformation is difficult to occur in the front end portion 102b having a shape with a gradually reduced diameter. In the high-pressure tank manufacturing device 10, a plurality of pins 22 and 32 are arranged in a manner of contacting the central portion 200a, and on the other hand, no pin is arranged in contact with the front end portion 102b. Thus, by arranging the pins 22 and 32 at effective positions, the number of pins can be suppressed.

[0049] In addition, the plurality of pins 22 and 32 are not limited to cylindrical shapes. For example, the portion of the plurality of pins 22 and 32 that contacts the intermediate body 200 may have a curved surface, such as a partial spherical surface. By reducing the contact area between the pins 22 and 32 and the intermediate body 200, it is possible to avoid the pins 22 and 32 interfering with the contact between the molten resin and the intermediate body 200. As a result, for example, the resin can be appropriately impregnated without moving the plurality of pins 22 and 32 to the separated position.

[0050] On the other hand, the shape of the plurality of pins 22 and 32 may be a shape that increases the contact area with the intermediate body 200. For example, the shape of the plurality of pins 22 and 32 may be formed in a shape that follows the surface shape of the intermediate body 200. By increasing the contact area between the pins 22 and 32 and the intermediate body 200, the contact pressure on the surface of the intermediate body 200, that is, the contact pressure on the fiber bundle 104 from the pins 22 and 32 can be reduced. Thus, it is possible to suppress the fiber bundle 104 from being dented due to the contact pressure with the pins 22 and 32.

[0051] The shapes of the plurality of pins 22 and 32 may be different. For example, a pin having a large contact area to reduce the contact pressure may be arranged at a portion of the intermediate body 200 where the deformation amount is large, and a pin having a small contact area may be arranged at a portion of the intermediate body 200 where the deformation amount is small. In this case, the pin having a small contact area may be fixed to the mold 11.

[0052] The embodiments of the present invention have been described in detail above, but these are only examples and do not limit the scope of the claims. The technology described in the scope of the claims includes various modifications and changes to the specific examples described above.

[0053] In addition, the technical elements described in this specification or drawings can be used alone or in various combinations to achieve technical usefulness, and are not limited to the combinations described in the scope of protection requested at the time of application. In addition, the technology exemplified in this specification or drawings can achieve multiple purposes at the same time, and achieving one of the purposes itself has technical usefulness.

Claims

1. A method for manufacturing a high-pressure tank, comprising manufacturing a high-pressure tank using a high-pressure tank manufacturing device, wherein the high-pressure tank manufacturing device comprises: A mold having a mold cavity for disposing an intermediate body, wherein the intermediate body has a fiber bundle wound on an inner liner; and The pin portion is arranged in a manner movable relative to the mold and moves between a contact position and a separation position, wherein the contact position is a position where the pin portion protrudes from the surface of the mold cavity into the mold cavity and contacts the intermediate body arranged in the mold cavity, and the separation position is a position where the pin portion is separated from the intermediate body arranged in the mold cavity. The pin portion is arranged so that, at the contact position, the molten resin flowing into the cavity can flow over the pin portion between the surface of the cavity and the intermediate body. The pin portion includes a plurality of pins, the plurality of pins protruding from the surface of the cavity in the same direction and arranged to be separated from each other. The intermediate body comprises: a cylindrical central portion extending in the longitudinal direction of the intermediate body; and front end portions at both ends of the central portion that gradually taper toward the front end. The plurality of pins are arranged at the central portion but not at the front end portion, The plurality of pins are configured to move from the contact position to the separation position before the molten resin solidifies, The pin having a large contact area is arranged at a portion of the intermediate body where the deformation amount is large, and the pin having a small contact area is arranged at a portion of the intermediate body where the deformation amount is small, and the pin having the small contact area is fixed relative to the mold. The high-pressure tank manufacturing method comprises: a placement step of placing the intermediate body in the cavity of the high-pressure tank manufacturing device and placing the pin portion at the contact position, wherein the intermediate body is formed by winding the fiber bundle around the liner; a filling step of injecting the molten resin into the cavity, causing the molten resin to flow between the surface of the cavity and the intermediate body over the pin portion, thereby filling the cavity with the molten resin; an impregnation step of impregnating the fiber bundle with the molten resin in the cavity; and a moving step of moving the pin having a large contact area from the contact position to the separation position and fixing the pin having a small contact area relative to the mold.

2. The method for manufacturing a high-pressure tank according to claim 1, wherein: In the moving step, before the molten resin is solidified in the cavity, the pin having a large contact area is moved from the contact position to the separation position, and the pin having a small contact area is fixed to the mold.

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