JP2010084908A - Gas tank, and method of manufacturing gas tank - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the weight of a gas tank while ensuring the strength of a mouthpiece and an end boss. <P>SOLUTION: The high-pressure gas tank 2 includes: a tank body 10 having a resin liner 20 and an FRP (fiber-reinforced plastic) layer 21 covering the resin liner 20; the mouthpiece 11 provided at one end in the tank axis direction of the tank body 10; and the end boss 12 made of resin and provided at the other end of the tank body 10. The other side end of the resin liner 20 is closed, and the end boss 12 is provided outside the other side end of the resin liner 20. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a gas tank and a method for manufacturing the gas tank.

  For example, in a fuel cell system mounted on an automobile or the like, a high-pressure gas tank is used as a fuel gas supply source. Generally, the main body of a high-pressure gas tank is formed by a liner which is an inner wall layer and a reinforcing fiber layer (outer wall layer) formed by winding fibers around the liner. A base to which a valve is connected is formed at one end in the axial direction of the tank body, and an end boss is formed at the other end to close the other end. The end boss is conventionally formed of the same metal as the base.

JP 09-96399 A JP 2003-287193 A

  By the way, it is desirable that the high-pressure gas tank is lighter from the viewpoint of the fuel consumption of the automobile and the transportability of the gas tank. However, the base and the end boss are made of metal, which makes the high-pressure gas tank heavy. On the other hand, the base and the end boss are required to have strength and durability against internal pressure. Further, since the valve is connected to the base, the strength to the valve is also required.

  This invention is made | formed in view of this point, and it aims at reducing the weight of a gas tank, ensuring the intensity | strength of a nozzle | cap | die and an end boss | hub.

  The present invention for achieving the above object is a gas tank, comprising a tank body having an inner wall layer and an outer wall layer covering the inner wall layer, and a base provided at one end of the tank body in the tank axial direction. A resin end boss provided at the other end of the tank body, the other end of the inner wall layer is closed, and the end boss is the other end of the inner wall layer. It is provided in the outer side of the edge part of the side.

  According to the present invention, since the end boss is made of resin, the weight of the gas tank can be reduced. Further, since the end boss side end of the inner wall layer of the tank body is closed and the end boss is provided on the outer side, the internal pressure of the gas tank is not directly applied to the end boss, and the strength of the end boss can be secured. Moreover, since only the end boss is made of resin, the strength of the die can be secured. Therefore, it is possible to reduce the weight of the gas tank while ensuring the strength of the base and the end boss.

  A closing surface is formed at the other end of the inner wall layer, and an opening is formed at the other end of the outer wall layer. The opening and the closing surface define the tank body. A recess may be formed at the other end, and the end boss may be installed in the recess.

  A gap is formed between the tip portion forming the opening of the outer wall layer and the inner wall layer inside thereof, and the end boss projects in a radial direction perpendicular to the tank axis so as to enter the gap. You may have a protrusion part. In such a case, since the end boss is locked in the gap between the inner wall layer and the outer wall layer, it is possible to prevent the end boss from being pushed out of the tank body when the internal pressure is increased, for example.

  The other end of the inner wall layer may be formed in a concave shape recessed inside the tank body, and the diameter of the concave portion of the inner wall layer may be formed larger than the opening of the outer wall layer. In such a case, a gap between the outer wall layer and the inner wall layer is appropriately formed.

  The end boss is made by removing the metal end boss attached to the other end of the tank body when the outer wall layer is formed by the filament wiping method, and pouring the molten resin into the recess formed thereby to cure the end boss. It may be formed by.

  According to another aspect of the present invention, there is provided a gas tank manufacturing method, the step of forming a base at one end in the axial direction of the inner wall layer of the tank body and forming a metal end boss at the other end; Rotating the inner wall layer of the tank body around an axis, winding a fiber around the inner wall layer to form an outer wall layer, removing the metal end boss, and removing the metal end boss at the other end of the tank body A step of forming a recess, and a step of pouring and melting a molten resin into the recess to form a resin end boss at the other end of the tank body.

  When the outer wall layer is formed, the strength of the end boss is required to hold the end boss and rotate the inner wall layer. According to the present invention, since a strong metal end boss can be used when forming the outer wall layer, the outer wall layer forming step can be performed appropriately. In addition, since the metal end boss is removed and molten resin is poured into the recess formed thereby to form the resin end boss, a gas tank having a resin end boss can be manufactured appropriately.

  According to the present invention, it is possible to reduce the weight of the gas tank while ensuring the strength of the base and the end boss.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram of a fuel cell vehicle 1 equipped with a gas tank according to the present embodiment.

  In the fuel cell vehicle 1, for example, three high-pressure gas tanks 2 are mounted on the rear portion of the vehicle body. The high-pressure gas tank 2 constitutes a part of the fuel cell system 3, and fuel gas can be supplied from each high-pressure gas tank 2 to the fuel cell 5 through the gas supply line 4. The fuel gas stored in the high-pressure gas tank 2 is a combustible high-pressure gas, for example, hydrogen gas. The high-pressure gas tank 2 is applicable not only to the fuel cell vehicle 1 but also to vehicles such as electric vehicles and hybrid vehicles, as well as various moving bodies (for example, ships, airplanes, robots, etc.) and stationary equipment (housing, buildings). it can.

  FIG. 2 is a longitudinal sectional view showing an outline of the configuration of the high-pressure gas tank 2. The high-pressure gas tank 2 includes, for example, a substantially ellipsoidal tank body 10, a base 11 provided at one end of the tank body 10 in the tank axial direction (left side in FIG. 2), and the other (right side in FIG. 2). An end boss 12 is provided at the end.

  The tank body 10 has, for example, a two-layer structure, and includes a resin liner 20 as an inner wall layer and an FRP (Fiber Reinforced Plastics) layer 21 as an outer wall layer covering the outer surface of the resin liner 20.

  The resin liner 20 has substantially the same ellipsoidal shape as the tank body 10. The resin liner 20 is formed of a polyamide-based resin such as nylon 6 or nylon 6,6. The FRP layer 21 is formed of a fiber containing a resin. As the resin of the FRP layer 21, for example, an epoxy resin, a modified epoxy resin, an unsaturated polyester resin, or the like is used. Moreover, as a fiber, carbon fiber, a metal fiber, etc. are used, for example.

  One end of the resin liner 20 is opened, and the base 11 is attached to the opening. The base 11 has a substantially cylindrical shape, and is formed of, for example, aluminum or iron. As shown in FIGS. 2 and 3, the other end of the resin liner 20 is closed, and a recessed portion 20 a that is recessed inside the tank body 10 is formed. The bottom surface of the concave portion 20a is a closed flat surface 20b orthogonal to the tank axis.

  An opening 21 a through which the end boss 12 passes is formed at the other end of the FRP layer 21. The diameter of the concave portion 20a of the resin liner 20 is formed to be larger than the diameter of the opening 21a of the FRP layer 21. Thus, the tip portion forming the opening 21a of the FRP layer 21 and the resin liner 20 inside thereof are formed. A gap D is formed between the two. A recess 22 is formed at the other end of the tank body 10 by the recessed portion 20 a of the resin liner 20 and the opening 21 a of the FRP layer 21, and the end boss 12 is installed in the recess 22. The end boss 12 has a substantially cylindrical shape that fits into the recess 22 and is formed of a resin such as a polyamide-based resin. Further, the end boss 12 has an annular projecting portion 12a projecting in the radial direction perpendicular to the tank axis so as to enter the gap D between the FRP layer 21 and the resin liner 20.

  Next, the manufacturing method of the high pressure gas tank 2 comprised as mentioned above is demonstrated. FIG. 4 is a flowchart showing an example of main steps of the manufacturing method.

  First, the resin liner 20 is injection molded. At this time, an opening is formed at one end of the resin liner 20, and a concave portion 20a having a closed flat surface 20b is formed at the other end. As shown in FIG. 5, the base 11 is attached to the opening at one end of the resin liner 20, and the end boss 12 'made of metal such as aluminum or iron is attached to the concave portion 20a at the other end. (Step S1 in FIG. 4). The end boss 12 ′ has substantially the same cylindrical shape as the end boss 12 finally formed. On the outer end surface of the end boss 12 ′, a recess 12 ′ a for inserting the rotating shaft 51 when forming the FRP layer 21 described later is formed.

  Thereafter, the resin liner 20 is supported by the rotating shaft 51 of the fiber winding device 50 as shown in FIG. The resin liner 20 is supported by the rotating shaft 51 by inserting the rotating shaft 51 into the caps 11 at both ends and the recess 12'a of the end boss 12 '.

  Thereafter, the rotating shaft 51 is rotated, the resin liner 20 is rotated, and the resin fibers F are wound around the outer surface of the resin liner 20. The resin fiber F is impregnated with a thermoplastic resin in the upstream portion, and then the angle is adjusted by the fiber guide portion 52 and wound around the resin liner 20. Thus, as shown in FIG. 7, the resin fiber F is wound around the outer peripheral surface of the resin liner 20, the base 11 and the outer peripheral surface of the end boss 12 ′, and the FRP layer 21 having a predetermined thickness is formed (FIG. 4). Step S2). Thereafter, the high-pressure gas tank 2 is heated and the FRP layer 21 is cured.

  After the FRP layer 21 is cured, the end bosses 12 ′ are dissolved and removed by acid (step S <b> 3 in FIG. 4). Thereby, as shown in FIG. 8, a recess 22 surrounded by the opening 21 a of the FRP layer 21 and the recess 20 a of the resin liner 20 is formed at the other end of the tank body 10. Thereafter, for example, the melted resin is poured into the recess 22 and cured to form the resin end boss 12 in the recess 22 as shown in FIG. 3 (step S4 in FIG. 4).

  According to the above embodiment, since the end boss 12 is made of resin, the weight of the high-pressure gas tank 2 can be reduced. In addition, since the end boss 12 side end of the resin liner 20 is closed and the end boss 12 is provided on the outer side, the internal pressure of the high-pressure gas tank 2 is not directly applied to the end boss 12, and the strength of the end boss 12 can be ensured. Further, since only the end boss 12 is made of resin, the strength of the base 11 can be secured. Therefore, the high pressure gas tank 2 can be reduced in weight while ensuring the strength of the base 11 and the end boss 12. Further, when the end boss 12 is made of resin, it becomes easy to set the durability and strength of the end boss 12 by changing the material and shape of the resin. Thereby, for example, the strength and durability of the tank body 10 are set lower, and the end boss 12 is broken before the tank body 10 is ruptured to release the internal gas, thereby preventing the tank body 10 from being ruptured. .

  A recess 22 surrounded by the closed flat surface 20 b of the resin liner 20 and the opening 21 a of the FRP layer 21 is formed at the other end of the tank body 10, and the end boss 12 is installed in the recess 22. In such a case, for example, the end boss 12 is firmly fixed to the tank body 10.

  A gap D is formed between the tip of the FRP layer 21 forming the opening 21a and the resin liner 20 on the inside thereof, and the end boss 12 protrudes radially outward so as to enter the gap D. 12a. For this reason, the end boss 12 is locked in the gap D between the resin liner 20 and the FRP layer 21, and the end boss 12 can be prevented from coming off from the tank body 10 when the internal pressure rises, for example.

  Further, since the diameter of the concave portion 12a formed at the other end of the resin liner 20 is larger than the opening 21a of the FRP layer 21, the gap D between the resin liner 20 and the FRP layer 21 is appropriately formed. Thus, the end boss 12 can be properly fixed to the tank body 10.

  In the present embodiment, a metal end boss 12 ′ is first formed on the other end of the tank body 10, and then an FRP layer 21 is formed by the FW method, and then the end boss 12 ′ is removed to form the tank body 10. A recess 22 is formed, and molten resin is poured into the recess 22 and cured to form the resin end boss 12. When the FRP layer 21 is formed, the end boss is held and rotated, so that the strength of the end boss is required. In the present embodiment, the metal end boss 12 ′ is used when forming the FRP layer 21. Therefore, the FRP layer 21 can be properly formed. Finally, the high-pressure gas tank 2 having the resin end boss 12 can be properly manufactured.

  In the above embodiment, the metal end boss 12 ′ is removed by dissolving with an acid, but the end boss 12 ′ may be removed by other methods. For example, as shown in FIG. 9, a metal end boss 12 ′ is formed in advance so as to be divided, and after the FRP layer 21 is formed, each piece P of the end boss 12 ′ is taken out from the recess 22 to remove the end boss 12 ′ May be.

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to such examples. It will be apparent to those skilled in the art that various changes or modifications can be made within the scope of the ideas described in the claims, and these are naturally within the technical scope of the present invention. It is understood that it belongs.

It is a schematic diagram of the fuel cell vehicle carrying a high pressure gas tank. It is a longitudinal cross-sectional view which shows the outline of a structure of a high pressure gas tank. It is an expanded longitudinal cross-sectional view of the edge part by the side of the end boss of a high pressure gas tank. It is a flowchart which shows the main processes of the manufacturing method of a high pressure gas tank. It is a longitudinal cross-sectional view which shows the outline of a structure of the resin liner which has a nozzle | cap | die and an end boss | hub. It is explanatory drawing which shows a mode that a resin fiber is wound around a resin liner. It is a longitudinal cross-sectional view of the high pressure gas tank in the state where the resin fiber was wound around the resin liner. It is an expanded sectional view of the edge part by the side of the end boss of a high pressure gas tank when metal end bosses are removed. It is a top view of the metal end boss | hub which can be divided | segmented.

Explanation of symbols

2 High-pressure gas tank 10 Tank body 11 Base 12 End boss 12 ′ End boss made of metal 20 Resin liner 20a Concave portion 21 FRP layer

Claims (6)

A gas tank,
A tank body having an inner wall layer and an outer wall layer covering the inner wall layer;
A base provided at one end of the tank body in the tank axial direction;
A resin end boss provided at the other end of the tank body,
The other end of the inner wall layer is closed;
The gas tank according to claim 1, wherein the end boss is provided outside an end of the other side of the inner wall layer. A closing surface is formed at the other end of the inner wall layer, and an opening is formed at the other end of the outer wall layer. The opening and the closing surface define the tank body. A recess is formed at the other end,
The gas tank according to claim 1, wherein the end boss is installed in the recess. A gap is formed between the tip portion forming the opening of the outer wall layer and the inner wall layer inside thereof,
The gas tank according to claim 2, wherein the end boss has a protruding portion protruding in a radial direction orthogonal to the tank axis so as to enter the gap.   The other end portion of the inner wall layer is formed in a concave shape recessed inside the tank body, and the diameter of the concave portion of the inner wall layer is formed larger than the opening of the outer wall layer. The gas tank according to claim 3.   The end boss is made by removing the metal end boss attached to the other end of the tank body when the outer wall layer is formed by the filament wiping method, and pouring the molten resin into the recess formed thereby to cure the end boss. The gas tank according to any one of claims 1 to 4, wherein the gas tank is formed as described above. A gas tank manufacturing method comprising:
Forming a base at one end in the axial direction of the inner wall layer of the tank body, and forming a metal end boss at the other end;
Rotating the inner wall layer of the tank body about an axis and winding the fiber around the outer wall layer to form an outer wall layer;
Removing the metal end boss and forming a recess in the other end of the tank body;
And a step of forming a resin end boss at the other end of the tank body by pouring molten resin into the concave portion and curing the molten resin.

Images