JP6474052B2 - Manufacturing method of high-pressure tank - Google Patents

Description

  The present invention relates to a method for manufacturing a high-pressure tank.

  The high-pressure tank may be mounted on a moving body such as a fuel cell vehicle, and its weight reduction is required. As such a high-pressure tank, there is known a tank in which a reinforcing layer (fiber reinforced resin layer) is provided on the outer periphery of a liner having a base and forming a hollow shape. This high-pressure tank is generally manufactured by a filament winding method (hereinafter also referred to as “FW method”).

  In the FW method, a fiber reinforced resin layer is formed by winding a reinforcing fiber impregnated with a thermosetting resin such as an epoxy resin around the outer periphery of a liner and thermosetting the thermosetting resin of the reinforcing fiber (for example, See Patent Document 1 below). Patent Document 1 below discloses that, in this FW method, a fiber reinforced resin layer is formed using a prepreg in which a fiber bundle is impregnated with a resin in advance.

JP 2008-286297 A

  As disclosed in Patent Document 1, in the method of manufacturing a high-pressure tank by winding a prepreg, the winding process tends to take a long time to ensure the strength of the high-pressure tank. In the case of increasing the production amount of the high-pressure tank by such a conventional method, many winding facilities are required, which may increase the cost of the high-pressure tank.

  This invention is made | formed in view of such a subject, The objective is to provide the manufacturing method of the high pressure tank which can shorten the time of a manufacturing process and can aim at cost reduction.

  In order to solve the above problems, a method for producing a high-pressure tank according to the present invention is a method for producing a cylindrical high-pressure tank having a liner reinforced by a carbon fiber reinforced resin layer, which is knitted into a cylindrical shape, A preparation step for preparing a prepreg having an opening in which one end side of the cylinder in the axial direction is closed and the other end side in the axial direction is opened, and after placing the prepreg in the mold, a parison is placed inside the prepreg, and blow molding A blow molding step of forming the liner; and a press-fitting step of press-fitting a base into the opening of the prepreg after the blow molding step, in the blow molding step, cooling the opening of the prepreg, Blow molding so that the outer diameter of the liner after blow molding is larger than the inner diameter of the prepared prepreg.

  According to this method, since the prepreg knitted in advance in a cylindrical shape is prepared and the high-pressure tank is manufactured, the prepreg winding step is not necessary, and the time for the high-pressure tank manufacturing process can be shortened. As a result, the cost of the high pressure tank can be reduced. In addition, the blower is blow-molded inside the prepreg so that the outer diameter of the liner after blow molding is larger than the inner diameter of the prepared prepreg, so the necessary tension is applied to the carbon fiber reinforced resin layer after blow molding. Can do. When such a blow molding process is adopted, there is a risk that the portion (opening) into which the die is press-fitted may be heated after molding the liner and the carbon fiber reinforced resin layer covering the outer periphery thereof, and the die is difficult to press-fit. There is a risk. Therefore, in the present invention, since the opening into which the die is press-fitted at the time of blow molding is cooled and the opening is prevented from being hardened, the die can be easily pressed. As a result, the time for manufacturing the high-pressure tank can be shortened, and the cost of the high-pressure tank can be reduced.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the high pressure tank which can shorten the time of a manufacturing process and can aim at cost reduction can be provided.

It is sectional drawing which shows schematic structure of the high pressure tank created by the manufacturing method of embodiment of this invention. It is a flowchart which shows an example of the manufacturing process of a high pressure tank. It is explanatory drawing explaining the manufacturing process of a high pressure tank.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. It should be noted that the following description of the preferred embodiment is merely an example, and is not intended to limit the present invention, its application, or its use.

  First, the structure of the high-pressure tank created by the manufacturing method of the embodiment of the present invention will be described. FIG. 1 is a cross-sectional view showing a schematic configuration of a high-pressure tank.

  A high-pressure tank 1 shown in FIG. 1 is a container for storing a fuel gas such as hydrogen or natural gas at a high pressure, and is mounted on a moving body such as an automobile. The high-pressure tank 1 includes a liner 20 used as an inner cylinder and a fiber reinforced resin layer 30 provided on the outside thereof.

  The liner 20 is a cylindrical inner shell having a storage space for storing gas therein. In this embodiment, the liner 20 is made of a synthetic resin material. However, the present invention is not limited to this example, and other materials can be used as the material used for the liner 20.

  A base 40 is provided on one end side of the liner 20. The base 40 is a member made of metal and serving as a gas or liquid pouring port accommodated in the high-pressure tank 1. In the present embodiment, the base 40 is formed only on one end side of the liner 20. However, the present invention is not limited to this example, and the base may be provided on one end side and the other end side of the liner 20.

  The fiber reinforced resin layer 30 (carbon fiber reinforced resin layer) is a layer made of carbon fiber reinforced plastic (CFRP) provided so as to cover the outer periphery of the liner 20. As will be described later, the fiber reinforced resin layer 30 is formed using CFRP containing a semi-cured resin called a prepreg. The prepreg is obtained, for example, by impregnating a liquid epoxy resin and polymerizing the resin to a semi-cured state by subsequent heating.

  Then, the manufacturing process of the high pressure tank as embodiment of this invention is demonstrated. FIG. 2 is a flowchart showing an example of a manufacturing process of the high-pressure tank. FIG. 3 is an explanatory diagram for explaining the manufacturing process of the high-pressure tank.

(Step S110)
First, the prepreg 3 impregnated with the resin is knitted into a bag shape by a predetermined circular knitting machine (not shown) (step S110 in FIG. 2 and FIG. 3A). The inner diameter a (FIG. 3A) of the prepreg 3 is set in advance so as to obtain a necessary tension when the high-pressure tank is completed. Preferably, the outer diameter of the liner 20 after blow molding described later is used. It is preferably set smaller than d (see FIG. 3E).

(Step S120)
Next, the knitted prepreg 3 is set in the mold 90 for forming a high-pressure tank (step S120 in FIG. 2 and FIG. 3B). As shown in FIG. 3B, the prepreg 3 has an opening 3a (post-process) in which one end of the cylinder in the axial direction is closed (lower side in FIG. 3) and the other end in the axial direction (upper side in FIG. 3) is opened. And the part into which the base is press-fitted. The dimension of the inner diameter b of the mold 90 is set to be larger than the dimension of the outer diameter A of the prepreg 3 (FIG. 3A). 3B to 3D, the illustration of the gap between the outer peripheral surface of the prepreg 3 and the inner peripheral surface of the mold 90 is omitted.

(Step S130)
Next, the cylindrical parison 2 for molding a high-pressure tank is sandwiched between the molds 90 (step S130 in FIG. 2 and FIG. 3C). The inner diameter c (FIG. 3C) of the opening 3a of the prepreg 3 is set to be larger than the outer periphery dimension e (FIG. 3E) that is press-fitted in a subsequent process.

(Step S140)
Next, air is blown into the parison 2 from the blowing port 91a of the blowing member 91 with guide, and a liner is formed by blow molding in order to secure a dimension capable of press-fitting the base 40 (FIG. 3E). At the same time that the liner is formed by this blow molding, tension is applied by spreading the prepreg 3 around the outer periphery of the liner. In this blow molding process, the temperature of the opening 3 a of the prepreg 3 is lowered by passing cooling water through the cooling unit 50 provided in the mold 90. Thus, by lowering the temperature of the opening 3a, the opening 3a can be prevented from being heated and cured.

  Note that the outer diameter A (FIG. 3A) of the cylindrical prepreg 3 is set smaller than the inner diameter b of the mold 90 (FIG. 3B), so that the inside of the mold 90 is blow molded. The prepreg 3 can be expanded. Moreover, as the cooling part 50 provided in the metal mold | die 90 shown in FIG.3 (D), it is not limited to let a cooling water pass, if it has the function to cool the opening part 3a, for example, compressed air ( It is also possible to select other methods such as air cooling.

(Step S150)
Next, the base 40 is press-fitted into the opening 3a of the cylindrical prepreg 3 (step S150 in FIG. 2 and FIG. 3E). At this time, since the temperature of the opening 3a is lowered, curing of the thermosetting resin around the opening 3a is suppressed, and the base 40 can be easily press-fitted into the opening 3a. Then, after covering the outer periphery of the base 40 with carbon fiber, the carbon fiber is pinched between the base 40 with a predetermined ring member 80 having an inner diameter tapered, and tension is applied. In a state where tension is applied using the ring member 80 in this way, the ring member 80 and the base 40 are bonded with a predetermined adhesive (not shown), and the upper portion of the base 40 protruding from the upper surface of the ring member 80 is attached. The ring member 80 and the base 40 are fixed by crushing with a roller punch (not shown).

(Step S160)
Finally, the tank body is heated to cure the epoxy resin, thereby creating a high-pressure tank including the fiber reinforced resin layer 30 covering the outer periphery of the liner 20. In the method for manufacturing a high-pressure tank according to the present embodiment, a prepreg 3 having an inner diameter dimension a (FIG. 3 (A)) smaller than the outer diameter dimension d (FIG. 3 (E)) of the liner 20 after blow molding is prepared. Since the parison 2 is placed inside and blow-molded, necessary tension can be applied to the prepreg 3.

  As described above, in the method for manufacturing the high-pressure tank 1 according to the present embodiment, the prepreg 3 is prepared that has an opening 3a that is knitted into a cylindrical shape and that is closed at one end in the axial direction of the cylinder and open at the other end in the axial direction. The pre-preg 3 is placed in the mold 90, the parison 2 is placed inside the prepreg 3, and the liner 20 is formed by blow molding. After the blow-molding step, the opening of the prepreg 3 A press-fitting step of press-fitting the cap 40 into 3a. In the blow molding step, the opening 3a of the prepreg 3 is cooled, and the outer diameter d of the liner 20 after blow molding is the inner diameter of the prepared prepreg 3. Blow molding to be larger than a.

  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 appropriately changed.

1: high pressure tank 2: parison 3: prepreg 3a: opening 20: liner 30: fiber reinforced resin layer 40: base 50: cooling unit 80: ring member 90: mold

Claims (1)

A method for producing a cylindrical high-pressure tank having a liner reinforced with a carbon fiber reinforced resin layer,
A preparation step of preparing a prepreg that is knitted into a cylindrical shape and has an opening in which one end in the axial direction of the cylinder is closed and the other end in the axial direction is opened;
After the prepreg is placed in a mold, a parison is placed inside the prepreg, and a blow molding step of forming the liner by blow molding;
A press-fitting step of press-fitting a base into the opening of the prepreg after the blow molding step;
In the blow molding step, the opening of the prepreg is cooled, and blow molding is performed so that the outer diameter of the liner after the blow molding is larger than the inner diameter of the prepared prepreg. Manufacturing method of high-pressure tank.

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