JP7533287B2 - High-pressure tank manufacturing device and high-pressure tank manufacturing method - Google Patents

Description

This specification discloses a high-pressure tank manufacturing apparatus and a high-pressure tank manufacturing method.

Patent Document 1 discloses a method for manufacturing a high-pressure tank. In this manufacturing method, a slide core that is provided to surround the resin injection port of a mold is moved from the cavity surface of the mold toward the intermediate body, so that the slide core comes into contact with the fiber bundle, and resin is injected from the resin injection port to impregnate the fiber bundle. By bringing the slide core into contact with the surface of the intermediate body during resin injection, the flow of resin is forcibly directed toward the inner layer of the fiber bundle, and the resin is impregnated up to the inner layer of the fiber bundle.

JP 2019-142118 A

The shape of the high-pressure tank is determined by the area in which it will be installed. The intermediate body of the high-pressure tank is made by winding a fiber bundle around the liner. The shape of the intermediate body is formed to match the shape of the high-pressure tank. For example, if the high-pressure tank has an elongated shape, the intermediate body is also formed in an elongated shape. Depending on the shape of the intermediate body, it may deform before being impregnated with the resin, and the intermediate body may come into contact with the surface of the cavity over a wide area.

In the area of the intermediate body's surface that is in contact with the cavity surface, the molten resin does not flow between the intermediate body and the cavity. As a result, the molten resin does not come into contact with the intermediate body's surface, and the molten resin cannot penetrate the intermediate body's surface. This can result in areas where the fiber bundle is not sufficiently impregnated with resin.

This specification provides a technology that prevents the intermediate from coming into contact with the surface of the cavity.

This specification discloses a high-pressure tank manufacturing device. The high-pressure tank manufacturing device includes a mold having a cavity in which an intermediate body having a liner wound with a fiber bundle is disposed, and a pin portion that is movably disposed relative to the mold and moves between a contact position where the pin portion protrudes from the surface of the cavity into the cavity and contacts the intermediate body disposed in the cavity, and a spaced position where the pin portion is spaced from the intermediate body disposed in the cavity, and the pin portion is disposed such 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.

This specification also discloses a method for manufacturing a high-pressure tank. This manufacturing method includes a placement step of placing an intermediate body having a fiber bundle wound around a liner in a cavity of the above-mentioned high-pressure tank manufacturing device, in which the pin portion is placed at a contact position; a filling step of injecting molten resin into the cavity and causing the molten resin to flow past the pin portion between the surface of the cavity and the intermediate body to fill the cavity with the molten resin; an impregnation step of impregnating the fiber bundle with the resin in the cavity; and a movement step of moving the pin portion from the contact position to a separated position.

According to the above configuration, the pin portion comes into contact with the intermediate body within the cavity, thereby preventing the intermediate body from coming into contact with the cavity surface. The molten resin can flow between the cavity surface and the intermediate body over the pin portion, preventing the flow of the molten resin from being impeded by the pin portion. In addition, by moving the pin portion from the contact position to the separated position, the molten resin can also come into contact with the surface of the intermediate body in the portion that was in contact with the pin portion.

FIG. 2 is a vertical cross-sectional view of the high-pressure tank manufacturing apparatus according to the embodiment. FIG. 2 is a vertical cross-sectional view of the high-pressure tank of the embodiment. FIG. 4 is a schematic diagram showing a flow of resin flowing through a cavity in an embodiment. 4 is a flowchart showing a method for manufacturing a high-pressure tank according to an embodiment. FIG. 4 is a longitudinal sectional view of the high-pressure tank manufacturing apparatus according to the embodiment, in which the pin portion is located in the separated position.

The technical elements of the thermal management device disclosed in this specification are listed below. Note that each of the technical elements below is useful independently.

The pin portion may include a plurality of pins that protrude in the same direction from the surface of the cavity and are spaced apart from one another.

With this configuration, multiple pins protruding in the same direction contact the intermediate body at multiple positions, thereby supporting the intermediate body. This makes it possible to prevent the intermediate body from contacting the cavity surface.

The intermediate body may have a cylindrical central portion extending in the longitudinal direction of the intermediate body, and tip portions at both ends of the central portion that gradually taper toward the tip, and the pin portion may be in contact with the central portion.

The tip portion of the intermediate body is gradually tapered, making it difficult to deform. On the other hand, the center portion of the intermediate body is cylindrical and therefore easy to deform. By bringing the pin portion into contact with the center portion, it is possible to bring the pin portion into contact with the center portion, which is more easily deformed.

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 hardens in the cavity.

With this configuration, uncured molten resin can be flowed into the space formed by the pin moving from the contact position to the separated position. This allows the resin to come into contact with the portion of the surface of the intermediate body that was in contact with the pin. This allows the resin to be impregnated into the fiber bundle from the surface of the intermediate body over the entire area of the intermediate body.

(Example)
As shown in FIG. 1, a high-pressure tank manufacturing apparatus 10 of this embodiment is used when manufacturing a high-pressure tank 100 (see FIG. 2).

(High pressure tank configuration)
First, the high-pressure tank 100 will be described with reference to Fig. 2. The high-pressure tank 100 is mounted on a fuel cell vehicle and stores a fuel gas such as natural gas or hydrogen gas. The high-pressure tank 100 includes a liner 102, a fiber bundle 104 impregnated with resin, and an annular member 106. The liner 102 is made of a resin material with gas barrier properties. The liner 102 has a cylindrical shape in a central portion 102a. A tip portion 102b of the liner 102 gradually becomes thinner as it moves away from the central portion 102a toward the end of the liner 102.

A fiber bundle 104 is disposed on the outer surface of the liner 102. The fiber bundle 104 is formed by winding carbon fiber around the outer surface of the liner 102. The fiber bundle 104 is disposed over the entire length of the liner 102. The fiber bundle 104 is formed by winding carbon fiber using a braiding method.

The fiber bundle 104 is sandwiched and held by the liner 102 and the annular member 106 at both ends of the high-pressure tank 100. The high-pressure tank manufacturing apparatus 10 is used to impregnate the fiber bundle 104 of the intermediate body 200, in which the fiber bundle 104 is wound around the liner 102 and held by the annular member 106, with resin. For this reason, the high-pressure tank manufacturing apparatus 10 can also be called the impregnation apparatus 10. In a modified example, the use of the high-pressure tank 100 is not limited to a tank that stores fuel gas for a fuel cell vehicle, and it may be a tank that has a similar structure to the above and stores high-pressure gas.

(Configuration of high pressure tank manufacturing equipment)
As shown in FIG. 1, the mold 11 includes a mold 11 and a pin portion 20. 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. An intermediate body 200 is placed 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 placed in the cavity 40, a small gap is formed between the cavity 40 and the intermediate body 200, which is large enough for molten resin to flow. Note that in FIG. 1 and FIG. 5, the gap between the cavity 40 and the intermediate body 200 is drawn large for ease of viewing.

The pin section 20 is attached to the upper mold 12. The pin section 20 includes a plurality of pins 22, a support plate 24, and an actuator 26. Each of the plurality of pins 22 has a cylindrical shape. The plurality of pins 22 are arranged in arrangement holes 42 that extend upward from the surface of the cavity 40 in the upper mold 12. Note that although the gap between the pin 22 and the arrangement hole 42 is depicted as being large in Figures 1 and 5, there is a gap between the pin 22 and the arrangement hole 42 that is large enough to prevent molten resin from flowing in.

The multiple pins 22 are arranged in the upper mold 12 at intervals in the longitudinal direction of the intermediate body 200 (i.e., the left-right direction in FIG. 1). The multiple pins 22 are arranged parallel to each other. The multiple pins 22 are attached to a support plate 24 at their upper ends. The support plate 24 is arranged so as 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, or the like. The multiple pins 22 are arranged so as to be movable in the vertical direction between a contact position in contact with the intermediate body 200 as shown in FIG. 1 and a separation position away from the intermediate body 200 as shown in FIG. 5 by the support plate 24 being moved in the vertical direction by the actuator 26. When the multiple pins 22 are arranged in the separation position, the lower end surfaces of the multiple pins 22 are located on the same plane as the surface of the cavity 40.

The pin section 30 is attached to the lower mold 14. The pin section 30 includes a plurality of pins 32, a support plate 34, and an actuator 36. Each of the plurality of pins 32 has a configuration similar to that of the plurality of pins 22. The plurality of pins 32 are arranged in arrangement holes 44 that extend upward from the surface of the cavity 40 in the lower mold 14. The relationship between the pins 32 and the arrangement holes 44 is the same as the relationship between the pins 22 and the arrangement holes 42.

The pins 32 are attached at their lower ends to a support plate 34 similar to the support plate 24. The support plate 34 is arranged so as to be movable in the vertical direction relative to the lower mold 14 by an actuator 36 similar to the actuator 26. As a result, the pins 32 are arranged so as to be movable in the vertical direction between a contact position in contact with the intermediate body 200 as shown in FIG. 1 and a separated position separated from the intermediate body 200 as shown in FIG. 5, by the support plate 34 being moved in the vertical direction by the actuator 36. When the pins 32 are arranged in the separated position, the lower end surfaces of the pins 32 are located on the same plane as the surface of the cavity 40.

As shown in FIG. 3, the lower mold 14 has support portions 16 that support both ends of the intermediate body 200. The support portions 16 support the annular members 106 of the intermediate body 200. This allows the intermediate body 200 to be supported within the mold 11. The lower mold 14 also has a plurality of flow paths 46 for filling the cavity 40 with resin. The plurality of flow paths 46 have a groove shape that guides the molten resin injected into the mold 11 from outside the mold 11 into the cavity 40.

(Manufacturing method of high pressure tank)
Next, a method for manufacturing the high-pressure tank 100 will be described. In the high-pressure tank 100, first, an intermediate body 200 is produced by arranging the fiber bundle 104 in the liner 102 and holding it with an annular member 106. The intermediate body 200 has a central portion 200a formed by the central portion 102a of the liner 102, and a tip portion 200b formed by the tip portion 102b of the liner 102. The central portion 200a has a cylindrical shape. The tip portion 200b is gradually tapered away from the central portion 200a toward the tip of the intermediate body 200.

Next, a resin impregnation process is performed to impregnate the fiber bundle 104 with resin. In the resin impregnation process, as shown in FIG. 1, resin is injected into the cavity 40 in which the intermediate body 200 is placed in the mold 11 attached to the equipment 300 (e.g., a press device), and pressure is applied to impregnate the fiber bundle 104 with resin, thereby performing so-called RTM (short for Resin Transfer Molding) molding.

As shown in FIG. 4, in the resin impregnation process, first, the upper mold 12 and the lower mold 14 of the mold 11 are separated, the intermediate body 200 is placed in the shape of the cavity 40 of the lower mold 14, and the intermediate body 200 is fixed by the support part 16 (S12). Next, the upper mold 12 and the lower mold 14 are closed. In the process of placing the intermediate body 200 in the mold 11, the multiple pins 22, 32 are placed in the contact position before the intermediate body 200 is placed. In a modified example, the multiple pins 22, 32 may be placed in the separated position when the intermediate body 200 is placed in the mold 11, and moved to the contact position after the intermediate body 200 is placed in the mold 11. The multiple pins 22, 32 are placed in a position that contacts the central part 200a of the intermediate body 200, but are not placed in a position that contacts the tip part 200b.

Next, molten resin is injected into the cavity 40 (S14). The injected resin is, for example, epoxy resin. Once the cavity 40 is filled with the resin, the resin in the cavity 40 is pressurized to a predetermined pressure (S16). Next, once the resin in the cavity 40 has been pressurized to the predetermined pressure, it is maintained at the predetermined pressure for a predetermined period of time (S18). This causes the resin to impregnate the fiber bundle 104.

As the resin is held under pressure and the impregnation progresses, the resin gradually hardens. In S20, before the resin completely hardens, the multiple pins 22, 32 are moved from the contact position to the separated position. As a result, the unhardened resin flows into the space formed by the movement of the multiple pins 22, 32. This allows the resin to be impregnated even from the position where the multiple pins 22, 32 were in contact.

Next, after the resin has hardened (S20), the upper die 12 and the lower die 14 are separated, and the molded high-pressure tank 100 is removed from the mold 11 (S22), completing the resin impregnation process.

(effect)
The intermediate body 200 may be manufactured in a distorted state relative to the design value due to the resin liner 102 being distorted during molding. When the intermediate body 200 is placed in the mold 11, the intermediate body 200 is supported by the support portion 16. When the intermediate body 200 is not distorted, a slight gap is formed between the surface of the cavity 40 and the intermediate body 200 so that the molten resin can flow in. However, since the intermediate body 200 is actually distorted, when both ends are supported by the support portion 16, the central portion 200a of the intermediate body 200 is bent. Note that if the gap between the intermediate body 200 and the surface of the cavity 40 is increased in order to avoid contact between the intermediate body 200 and the surface of the cavity 40, the amount of resin required for impregnation increases.

In the high-pressure tank manufacturing apparatus 10, pin portions 20, 30 are arranged to protrude into the cavity 40. With this configuration, the pin portions 20, 30 can support the bent intermediate body 200 so that it does not come into contact with the surface of the cavity 40. This maintains a gap between the intermediate body 200 and the surface of the cavity 40. As a result, as shown in FIG. 3, 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.

The multiple pins 22, 32 are arranged at a distance from the flow path 46. The multiple pins 22, 32 are also arranged at a distance from each other in the cavity 40. Therefore, the molten resin flowing between the intermediate body 200 and the cavity 40 can flow over the multiple pins 22, 32 without being blocked by the multiple pins 22, 32. This makes it possible to avoid a situation in which the flow of the molten resin is obstructed by the multiple pins 22, 32. In addition, in the 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 be arranged above the cavity 40 in the upper mold 12. There is also no limit to the number of flow paths. In any case, the pin portions 20, 30 do not have an arrangement or shape that obstructs the flow of the molten resin flowing in the cavity 40.

The multiple pins 22 also protrude from the surface of the cavity 40 in the same direction (i.e., downward). With this configuration, the multiple pins 22 can suppress distortion of the intermediate body 200. This can prevent the intermediate body 200 from bending in the direction in which the multiple pins 22 protrude and coming into contact with the surface of the cavity 40. The same applies to the multiple pins 33.

By moving the multiple pins 22, 32 from the contact position to the separated position before the molten resin hardens, the resin can be impregnated from the position where the multiple pins 22, 32 were in contact. This makes it possible to prevent the occurrence of areas that are impregnated with the resin properly.

The multiple pins 22, 32 are arranged in the central portion 200a of the intermediate body 200, but are not arranged in the tip portion 200b of the intermediate body 200. In the liner 102, distortion is likely to occur in the cylindrical central portion 102a, but distortion is unlikely to occur in the tip portion 102b, which has a shape that gradually reduces in diameter. In the high-pressure tank manufacturing device 10, the multiple pins 22, 32 are arranged so as to contact the central portion 200a, but no pins are arranged to contact the tip portion 102b. In this way, the number of pins can be reduced by arranging the pins 22, 32 in effective positions.

The multiple pins 22, 32 are not limited to a cylindrical shape. For example, the portion of the multiple pins 22, 32 that contacts the intermediate body 200 may have a curved surface, for example, a partially spherical shape. By reducing the contact area between the pins 22, 32 and the intermediate body 200, it is possible to prevent the pins 22, 32 from 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 multiple pins 22, 32 to a separated position.

On the other hand, the shape of the multiple pins 22, 32 may be such that the contact area with the intermediate body 200 is increased. For example, the shape of the multiple pins 22, 32 may be formed to conform to the surface shape of the intermediate body 200. By increasing the contact area between the pins 22, 32 and the intermediate body 200, the contact pressure that the surface of the intermediate body 200, i.e., the fiber bundle 104, receives from the pins 22, 32 can be reduced. This makes it possible to prevent the fiber bundle 104 from being depressed by the contact pressure with the pins 22, 32.

The shapes of the multiple pins 22, 32 do not have to be the same. For example, a pin with a large contact area may be placed in a location where the distortion of the intermediate body 200 is large in order to reduce contact pressure, while a pin with a small contact area may be placed in a location where the distortion of the intermediate body 200 is small. In this case, the pin with the small contact area may be fixed to the mold 11.

The above describes the embodiments of the present invention in detail, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and variations of the specific examples given above.

The technical elements described in this specification or drawings have technical utility either alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. The technologies illustrated in this specification or drawings achieve multiple objectives simultaneously, and achieving any one of those objectives is itself technically useful.

10: High pressure tank manufacturing equipment (impregnation equipment), 11: Mold, 12: Upper mold, 14: Lower mold, 16: Support part, 20, 30: Pin part, 22, 32: Pin, 26, 36: Actuator, 40: Cavity, 100: High pressure tank, 200: Intermediate body, 200a: Center part, 200b: Tip part

Claims (3)

a mold having a cavity in which an intermediate body having a liner and a fiber bundle wound thereon is placed;
a pin portion that is movably disposed relative to the mold and moves between a contact position where the pin portion protrudes from a surface of the cavity into the cavity and contacts the intermediate body disposed in the cavity, and a spaced position where the pin portion is spaced from the intermediate body disposed in the cavity;
the pin portion is disposed such 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 protruding in the same direction from the surface of the cavity and spaced apart from one another;
The intermediate body includes a cylindrical central portion extending in a longitudinal direction of the intermediate body, and tip portions at both ends of the central portion that gradually taper toward the tip,
the plurality of pins contact the central portion but do not contact the tip portion;
High pressure tank manufacturing equipment. A placement step of placing an intermediate body in which a fiber bundle is wound around a liner in a cavity of the high-pressure tank manufacturing apparatus according to claim 1 , the placement step being such that a pin portion is placed at a contact position;
a filling step of injecting the molten resin into the cavity and causing the molten resin to flow over the pin portion between the surface of the cavity and the intermediate body to fill 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 portion from the contact position to a separated position. The high-pressure tank manufacturing method according to claim 2 , wherein in the moving step, the pin portion is moved from the contact position to the separated position before the molten resin hardens in the cavity.

Images