JP2018083391A - Method for manufacturing hydrogen tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a hydrogen tank, capable of increasing the pressure-proof performance while shortening the manufacturing lead time.SOLUTION: Manufacturing of a hydrogen tank 1 includes: a first step of fixing a cap 5 to an opening 221 of a hollow vessel 2 made of metallic material and inserting a preform 31 integrated with the cap 5 inside a hollow vessel 2; a second step of blowing the preform 31 through the cap 5 fixed to the opening 221 so as to be inflated and integrated with the hollow vessel 2; and a third step of forming a reinforcement layer 4 for reinforcing a hollow vessel 2 on the outside surface 2b of the hollow vessel 2.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a method for manufacturing a hydrogen tank.

  Development of a fuel cell vehicle equipped with a fuel cell system and traveling using electric power generated by the fuel cell has been underway. A fuel cell mainly receives supply of hydrogen gas and oxidant gas, and generates electric power by causing an electrochemical reaction.

  The fuel cell vehicle is equipped with a hydrogen tank that stores hydrogen gas. Since hydrogen gas is stored at a high pressure of 700 to 2000 atmospheres, a high pressure resistance is required for the hydrogen tank. In order to reduce the weight, a hydrogen tank formed using a resin material has been proposed.

  Patent Document 1 discloses a method for manufacturing a hydrogen tank. The hydrogen tank has a tank liner disposed therein and a reinforcing layer provided outside the tank liner. The tank liner is formed by injection molding a resin material.

JP 2006-300207 A

  In the manufacturing method described in Patent Document 1, the tank liner is formed by joining two divided bodies formed in advance. As described above, since a high pressure resistance is required for the hydrogen tank, high accuracy is required for the joining work of the divided bodies. For this reason, the manufacturing method described in Patent Document 1 has a problem that lead time is deteriorated.

  The present invention has been made in view of such problems, and an object of the present invention is to provide a method for manufacturing a hydrogen tank capable of improving pressure resistance performance while shortening the manufacturing lead time.

  In order to solve the above-described problems, a method for producing a hydrogen tank according to the present invention includes attaching a base to an opening of a hollow container made of a metal material, and placing a preform integrated with the base inside the hollow container. The first step of inserting, the second step of expanding the preform and integrating it with the hollow container by blowing through a base attached to the opening, and winding the carbon fiber on the outer surface of the hollow container And a third step of forming a reinforcing layer for reinforcing the hollow container.

  According to the above method, since the tank liner is formed by blow molding, the step of forming the tank liner by joining becomes unnecessary. Therefore, it is possible to shorten the manufacturing lead time.

  Moreover, according to the said method, since a preform is blown inside a hollow container, the metal mold | die used only for blow molding is unnecessary. In other words, according to the above method, the hollow container that functions as a blow mold is used as a member constituting the hydrogen tank after blow molding. Generally, the pressure acting on the mold in blow molding is smaller than the pressure acting on the mold in injection molding. Therefore, in the above method, it is possible to employ a relatively thin hollow container. As a result, it is possible to improve the pressure resistance performance of the hydrogen tank using a hollow container formed of a metal material while suppressing an increase in the weight of the hydrogen tank.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the hydrogen tank which can improve pressure | voltage resistant performance can be provided, shortening manufacturing lead time.

It is sectional drawing of the hydrogen tank which concerns on embodiment. It is sectional drawing which shows an insertion process. It is sectional drawing which shows a blow process. It is sectional drawing which shows a winding process.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In order to facilitate the understanding of the description, the same constituent elements in the drawings will be denoted by the same reference numerals as much as possible, and redundant description will be omitted.

  First, the configuration of the hydrogen tank 1 according to the embodiment will be described with reference to FIG. The hydrogen tank 1 constitutes a part of a fuel cell system mounted on a fuel cell vehicle (not shown). The hydrogen tank 1 is a container in which a space 10 is formed, and its shape is substantially rotationally symmetric about a center line CA. FIG. 1 is a cross-sectional view of the hydrogen tank 1 in a plane including the center line CA.

  The hydrogen tank 1 includes a hollow container 2, a tank liner 3, a reinforcing layer 4, and a base 5.

  The hollow container 2 is formed of a metal material that exhibits a predetermined rigidity, such as stainless steel or an aluminum alloy. The hollow container 2 is formed by rolling a steel plate, and has a body portion 21 and side walls 22 and 23. The trunk | drum 21 is exhibiting the cylinder shape extended along the centerline CA. The side walls 22 and 23 are disposed at the end portion of the body portion 21 and close both end portions of the body portion 21. The side wall 22 has an opening 221 that communicates the inside and outside of the hollow container 2.

  The tank liner 3 is disposed inside the hollow container 2. The tank liner 3 is made of a resin material such as polyethylene or polypropylene. The tank liner 3 covers the entire inner surface 2 a of the hollow container 2.

  The reinforcing layer 4 is disposed so as to cover the outer surface 2 b of the hollow container 2. Specifically, the reinforcing layer 4 covers the outer surface 2 b of the portion corresponding to the trunk portion 21. The reinforcing layer 4 is, for example, an FRP layer (CFRP) formed by reinforcing an epoxy resin with carbon fiber. In addition to the epoxy resin, for example, a modified epoxy resin, an unsaturated polyester resin, a polypropylene resin, or the like can be used. The material forming the reinforcing layer 4 preferably has a linear expansion coefficient smaller than that of the resin material forming the tank liner 3.

  The base 5 is a member formed of a metal material such as stainless steel or aluminum alloy. The base 5 has a cylindrical portion 51 and a flange portion 52. The cylindrical portion 51 has a cylindrical shape, and a passage 51a is formed therein. The flange portion 52 is formed so as to protrude in the radial direction from the outer peripheral surface of the cylindrical portion 51. The base 5 is attached so that the cylindrical portion 51 is disposed in the opening 221 of the hollow container 2 and the flange portion 52 is in contact with the side wall 22. For attaching the base 5 to the hollow container 2, various methods such as screwing, welding, brazing and the like can be adopted.

  As described above, the hydrogen tank 1 is a container having a multilayer outer shell composed of the hollow container 2, the tank liner 3, and the reinforcing layer 4. The hydrogen tank 1 stores hydrogen gas supplied at a hydrogen station or the like through the passage 51 a of the base 5 and stored in the space 10. Further, the hydrogen tank 1 causes the hydrogen gas stored in the space 10 to flow out through the passage 51 a of the base 5. The hydrogen gas that has flowed out is led to the fuel cell by a pipe (not shown) and consumed in the electrochemical reaction during power generation. The base 5 may have a valve function for switching between opening and closing of the passage 51a.

  Next, a method for manufacturing the hydrogen tank 1 will be described with reference to FIGS. The manufacturing method includes at least an insertion process, a blowing process, and a winding process. 2 to 4 are all cross-sectional views in a plane including the center line CA.

  FIG. 2 shows the state of the insertion process. In the insertion step, the preform 31 is inserted into the space 20 formed inside the hollow container 2 as indicated by the arrow A. The preform 31 is a prototype of the tank liner 3. One end of the preform 31 is closed and the other end is integrated with the end of the cylindrical portion 51 of the base 5. The preform 31 is preheated and softened. A pressure curable resin (not shown) is applied in advance to the inner surface 2 a of the hollow container 2.

  The insertion process is completed by attaching the flange portion 52 of the base 5 so as to contact the side wall 22. The preform 31 inserted into the space 20 of the hollow container 2 is arranged with a gap between the inner surface 2a.

  FIG. 3 shows a blow process performed after the insertion process. In the blowing process, as indicated by an arrow B, air is supplied to the space 310 inside the preform 31 through the passage 51 a of the base 5. The preform 31 is expanded by the pressure of the supplied air. At this time, a tubular member (not shown) may be inserted from the passage 51a of the base 5 and air may be supplied through the tubular member.

  The expanding preform 31 is in close contact with the inner surface 2 a of the hollow container 2. When the preform 31 is cooled and cured, the tank liner 3 having a shape along the inner surface 2a of the hollow container 2 is formed.

  The expanding preform 31 pressurizes the pressure curable resin applied to the inner surface 2a. At this time, the pressure curable resin enters the irregularities on the surface of the preform 31. Therefore, when the pressurized pressure curable resin is cured, the tank liner 3 is brought into close contact with the inner surface 2a by the anchor effect.

  FIG. 4 shows a winding process performed after the blowing process. In the winding step, for example, carbon fibers 41 impregnated with a thermosetting resin such as epoxy are used. The carbon fiber 41 is wound around the outer surface 2b of the hollow container 2 by a filament winding method.

  The carbon fiber 41 is wound only on the trunk portion 21 without being wound around the side walls 22 and 23 of the hollow container 2. The carbon fibers 41 are wound so as to overlap in order to form a predetermined thickness on the outer side surface 2b of the trunk portion 21. After winding, the thermosetting resin contained in the carbon fiber 41 is cured to form the reinforcing layer 4 (see FIG. 1) that covers the outer surface 2b.

  According to such a method for manufacturing the hydrogen tank 1, since the tank liner 3 is formed by blow molding, the step of forming the tank liner 3 by joining is not necessary. Therefore, it is possible to shorten the manufacturing lead time.

  Moreover, according to the said method, since the preform 31 is blown inside the hollow container 2, the metal mold | die used only for blow molding is unnecessary. In other words, according to the above method, the hollow container 2 that functions as a blow molding die is used as a member constituting the hydrogen tank 1 after blow molding. Generally, the pressure acting on the mold in blow molding is smaller than the pressure acting on the mold in injection molding. Therefore, in the above method, a relatively thin hollow container 2 can be employed. As a result, the pressure resistance performance of the hydrogen tank 1 can be enhanced using the hollow container 2 formed of a metal material while suppressing an increase in the weight of the hydrogen tank 1.

  The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. In other words, those specific examples that have been appropriately modified by those skilled in the art are also included in the scope of the present invention as long as they have the characteristics of the present invention. Each element included in each of the specific examples described above and their arrangement, material, condition, shape, size, and the like are not limited to those illustrated, and can be changed as appropriate.

1: Hydrogen tank 2: Hollow container 3: Tank liner 4: Reinforcement layer 5: Base 31: Preform

Claims (1)

A method for producing a hydrogen tank, comprising:
A first step of attaching a base to the opening of a hollow container formed of a metal material and inserting a preform integrated with the base into the hollow container;
A second step in which the preform is expanded and integrated with the hollow container by blowing through the base attached to the opening;
And a third step of forming a reinforcing layer that reinforces the hollow container on the outer surface of the hollow container.

Images