JP2009293742A - Tank - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tank having high durability and strength, by preventing excessive stress from being applied to a fitting part. <P>SOLUTION: This high pressure tank 2 has the cylindrical fitting part 11 and a FRP layer 21 of a tank body attached with the fitting part 11. The FRP layer 21 of the tank body contacts in a part with an outer peripheral surface of the fitting part 11, and an inner layer 21a of the FRP layer 21 of the tank body is formed softer than an outer layer 21b. The FRP layer 21 is constituted of resin including fiber, and the inner layer 21a is softened by increasing the content of resin. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a tank having a base part and a wall layer of a tank body in contact with the base part.

  For example, in a fuel cell system mounted on a vehicle such as an automobile, a high-pressure tank is used as a fuel gas supply source. As this type of tank, for example, a tank described in Patent Document 1 is known. This tank is, for example, a tank body in which the outer peripheral surface of a liner layer (inner wall layer) is reinforced with an FRP (Fiber Reinforced Plastics) layer (outer wall layer), and a cylindrical shape attached to the longitudinal opening end of the tank body. It has a base part.

  The base part is attached, for example, in a state of being fitted into the opening end part of the tank body, and the wall layer of the tank body constituting the opening end part is in airtight contact with the outer peripheral surface of the base part.

JP 2007-155116 A JP 2000-266289 A Japanese Unexamined Patent Publication No. 7-310895

  By the way, when a high-pressure gas is sealed in the tank as described above, an internal pressure is applied to the wall layer of the tank body, and an excessive stress may be applied to the base portion contacting the wall layer. If excessive stress is applied to the base part, it may cause cracks in the base part when used for a long period of time, for example.

  This invention is made | formed in view of this point, and it aims at providing the tank which prevents that an excessive stress is applied to a nozzle | cap | die part and has high durability and intensity | strength.

  The present invention for achieving the above object is a tank having a cylindrical base part and a wall layer of a tank body to which the base part is attached, wherein the wall layer of the tank body is partially One part including the at least part of the wall layer of the tank body that is in contact with the outer peripheral surface of the base part is formed to be softer than the other part.

  According to the present invention, since the portion of the tank body wall layer that comes into contact with the base portion is formed softly, the stress applied to the base portion is dispersed and averaged through the wall layer of the tank body, and the base portion is excessive. It is possible to prevent stress from being applied. As a result, the durability and strength of the tank can be improved.

  The part of the wall layer of the tank main body may be formed such that the central side in the axial direction of the base part is thicker than the end part side on the outer peripheral surface of the base part.

  The wall layer of the tank body may be formed so that the outer peripheral surface side is harder than the inner peripheral surface side where the part is present.

  The wall layer of the tank body may be hardened stepwise from the inner peripheral surface side toward the outer peripheral surface side.

  The wall layer of the tank body may be composed of resin-containing fibers, and the one portion may be softened by increasing the resin content.

  According to another aspect of the present invention, there is provided a tank having a cylindrical base portion having a concave portion recessed inwardly on an outer peripheral surface, and a wall layer of a tank body partially entering the concave portion of the base portion, An elastic member is interposed between the wall layer of the tank body and the concave portion of the base part.

  According to the present invention, since the elastic member is interposed between the base part and the wall layer of the tank body, the stress applied to the base part through the wall layer of the tank body is dispersed and averaged. It is possible to prevent excessive stress from being applied to the base part. As a result, the durability and strength of the tank can be improved.

  According to another aspect of the present invention, there is provided a tank having a cylindrical base portion having a concave portion recessed inwardly on an outer peripheral surface, and a wall layer of a tank body partially entering the concave portion of the base portion, The entire wall layer of the tank body is made of a flexible material.

  According to the present invention, since the entire wall layer of the tank body is made of a flexible material, the stress applied to the base part is dispersed and averaged through the wall layer of the tank body, and excessive stress is applied to the base part. Can be prevented. As a result, the durability and strength of the tank can be improved.

  The wall layer of the tank body may be composed of resin-containing fibers, and a soft resin may be used as the resin.

  According to the present invention, it is possible to prevent an excessive stress from being applied to the cap portion, so that the durability and strength of the tank can be improved.

  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 tank according to the present embodiment.

  In the fuel cell vehicle 1, for example, three high-pressure tanks 2 are mounted on the rear portion of the vehicle body. The high-pressure tank 2 constitutes a part of the fuel cell system 3, and fuel gas can be supplied from each high-pressure tank 2 to the fuel cell 5 through the gas supply line 4. The fuel gas stored in the high-pressure tank 2 is a combustible high-pressure gas, such as compressed natural gas or hydrogen gas. The high-pressure 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 cross-sectional view showing a main part of the high-pressure tank 2. The high-pressure tank 2 has, for example, a substantially ellipsoidal tank main body 10 and a base 11 attached to one end of the tank main body 10 in the longitudinal direction. In the present embodiment, the side on which the cap part 11 is attached is the front of the high-pressure tank 2.

  The tank body 10 has, for example, a two-layer wall layer, and has a liner 20 as an inner wall layer and an FRP layer 21 as a resin-containing fiber layer as an outer wall layer on the outer side thereof.

  The liner 20 has substantially the same ellipsoidal shape as the tank body 10. The liner 20 is made of, for example, polyethylene resin, polypropylene resin, or other hard resin.

  A folded portion 30 that is bent inward is formed on the front end side of the liner 20 where the base portion 11 is located. The folded portion 30 is folded toward the rear of the tank body 10 so as to be separated from the outer FRP layer 21. The folded portion 30 has, for example, a curved shape that curves convexly inward (axis Y side). The opening portion of the liner 20 is formed by the folded portion 30.

  The base 11 has a substantially cylindrical shape and is fitted into the opening of the liner 20. The base portion 11 is made of, for example, aluminum or an aluminum alloy, and is manufactured in a predetermined shape by, for example, a die casting method. The base part 11 is attached to the liner 20 by insert molding, for example.

  An annular flange 11 a is formed around the axis on the outer peripheral surface of the base portion 11, for example, at the front end. On the rear side of the flange 11a, an annular recess 11b is formed around the axis. The dent 11b is curved in a convex shape toward the axis Y (inner side) and has an R shape. Similarly, the front end of the R-shaped FRP layer 21 is in airtight contact with the recess 11b.

  On the further rear side of the recessed portion 11b of the base portion 11, for example, a large diameter portion 11c having a large diameter is formed continuously from the recessed portion 11b. An annular recess 11d is formed around the axis on the rear side of the large diameter portion 11c. The recessed portion 11d is curved in a convex shape on the shaft side and has an R shape. The folded portion 30 of the liner 20 is formed so as to be in close contact with the outer peripheral surfaces of the large diameter portion 11c and the recessed portion 11d.

  For example, a screw part 40 is formed on the inner peripheral surface of the base part 11 on the axis Y side, and a valve assembly 50 is inserted and screwed. The valve assembly 50 controls, for example, supply and discharge of fuel gas between an external gas supply line and the inside of the high-pressure tank 2. Seal members 60 and 61 are interposed between the inner peripheral surface of the base 11 and the outer peripheral surface of the valve assembly 50.

  The FRP layer 21 is formed, for example, by winding a reinforcing fiber impregnated with a resin around the outer peripheral surface of the liner 20 and the concave portion 11b of the outer peripheral surface of the base portion 11 and curing the resin by a filament winding method. For 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. Further, as the reinforcing fiber, carbon fiber, metal fiber, or the like is used.

  The FRP layer 21 has, for example, a two-layer structure of an inner layer 21a as one portion that contacts the base portion 11 and the liner 20 and an outer layer 21a as another portion outside the FRP layer 21. The inner layer 21a has, for example, a soft resin content higher than the outer layer 21b on the outer side, and is softer than the outer layer 21b. Thereby, the inner layer 21a of the FRP layer 21 functions as a cushion material. In the present embodiment, the inner layer 21 a includes a part (front end portion) of the FRP layer 21 in contact with the base portion 11.

  According to the high-pressure tank 2 having the above configuration, the inner layer 21a of the FRP layer 21 in contact with the base part 11 is softer than the outer layer 21b. For this reason, for example, when a high-pressure gas is sealed in the high-pressure tank 2 and an internal pressure is applied to the tank body 10 and a force acts on the base portion 11 from the FRP layer 21, the flexibility of the inner layer 21a of the FRP layer 21 The power is distributed. Therefore, the stress applied to the base part 11 is dispersed and averaged, and an excessive stress is prevented from being applied to the base part 11. As a result, the durability and strength of the high-pressure tank 2 can be improved.

  FIG. 3 shows a simulation result for demonstrating the effect when the contact portion between the FRP layer 21 and the base portion 11 is provided with cushioning properties. In this simulation, the stress applied to the base part 11 is calculated using a finite element method (FEM) analysis, and (a) does not give a cushioning property to the contact part between the FRP layer 21 and the base part 11. (B) is a case where the contact portion between the FRP layer 21 and the base portion 11 is provided with cushioning properties. Assuming that the maximum stress applied to the base part 11 in the case of (a) is 100, the maximum stress applied to the base part 11 in the case of (b) was about 62. As described above, it can be confirmed that the maximum stress applied to the base part 11 is reduced by providing the contact portion between the FRP layer 21 and the base part 11 with cushioning properties.

  In the above embodiment, the outer layer 21b harder than the inner layer 21a is formed outside the inner layer 21a of the FRP layer 21, so that the entire elasticity of the FRP layer 21 is sufficiently ensured. Further, the overall strength of the FRP layer 21 is also maintained.

  In the above embodiment, the FRP layer 21 has two levels of hardness, the inner layer 21a and the outer layer 21b. However, as shown in FIG. 4, the FRP layer 21 has three levels of hardness from the inside to the outside. You may change to In such a case, the content ratio of the resin to the carbon fiber is lowered in the order of the inner layer 21a, the intermediate layer 21c, and the outer layer 21b of the FRP layer 21. By doing so, as the FRP layer 21 goes outward, it becomes harder in steps, and both the strength and cushioning properties of the FRP layer 21 can be sufficiently secured. The FRP layer 21 may change in hardness by four or more levels from the inside to the outside.

  In the above embodiment, the thickness of the inner layer 21a of the FRP layer 21 in contact with the base part 11 is substantially constant, but the inner layer 21a is pivoted on the outer peripheral surface of the recessed part 11b of the base part 11 as shown in FIG. The central portion side in the direction may be thick and the front and rear end portions may be thin. For example, the inner layer 21a is first thinned and then gradually thickened from the front side to the rear side of the recess 11b, and then gradually thinned. By doing so, the maximum stress applied to the vicinity of the central portion of the recessed portion 11b of the base portion 11 is easily dispersed in the front-rear direction. Therefore, the maximum stress applied to the base part 11 can be suitably reduced.

  In the above embodiment, the inner layer 21a of the FRP layer 21 is made softer than the outer layer 21b, and the cushioning property of the contact portion between the FRP layer 21 and the base part 11 is ensured. An elastic member may be interposed between 11b and the FRP layer 21. FIG. 6 shows such an example. For example, a rubber material 70 is interposed between the recess 11 b of the base 11 and the FRP layer 21. By doing so, the force acting on the recess 11b of the base part 11 from the FRP layer 21 is absorbed by the rubber material 70, and the stress applied to the base part 11 is dispersed and averaged. As a result, excessive stress is prevented from being applied to the base 11.

  In this example, an elastic resin or the like may be interposed between the recess 11b and the FRP layer 21 instead of the rubber material 70.

  Furthermore, as shown in FIG. 7, the entire FRP layer 21 may be made of a flexible material. For example, as the carbon fiber-containing resin of the FRP layer 21, for example, a soft resin such as a soft epoxy resin having a Young's modulus of 10 GPa (gigapascal) (general epoxy resin hardness) or less, preferably 5 GPa or less is used. In such a case, the FRP layer 21 is made of soft resin-containing carbon fiber having flexibility. In this case, due to the flexibility of the FRP layer 21, the stress acting on the recess 11b of the base part 11 from the FRP layer 21 is dispersed and averaged. As a result, excessive stress is prevented from being applied to the base 11. In addition, as a material which has a softness | flexibility, what has the hardness of 5 GPa or less is preferable, for example.

  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 and 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.

  For example, in the above embodiment, the structure of the wall layer of the tank body 10 is not limited to the double structure of the liner 20 and the FRP layer 21, and may be another structure.

It is a schematic diagram of a fuel cell vehicle equipped with a high-pressure tank. It is an expanded sectional view of the important section of a high pressure tank. Explanation of simulation results of stress applied to the base part when the contact part between the FRP layer and the base part is not cushioned and when the contact part between the FRP layer and the base part is cushioned FIG. It is an expanded sectional view of the important section of a high-pressure tank at the time of forming a FRP layer in three layers. It is an expanded sectional view of the important section of a high-pressure tank at the time of changing the thickness of the inner layer of a FRP layer. It is an expanded sectional view of the important section of a high-pressure tank at the time of interposing a rubber material between a FRP layer and a dent part of a mouthpiece part. It is an expanded sectional view of the important section of a high-pressure tank at the time of giving flexibility to the whole FRP layer.

Explanation of symbols

2 High-pressure tank 10 Tank body 11 Cap portion 11b Recessed portion 21 FRP layer 21a Inner layer 21b Outer layer

Claims (8)

A tank having a cylindrical base part and a wall layer of a tank body to which the base part is attached,
A part of the wall layer of the tank body is in contact with the outer peripheral surface of the base part,
One part including at least the part of the wall layer of the tank body is formed to be softer than the other part.   The part of the wall layer of the tank main body is formed so that the central side in the axial direction of the base part is thicker than the end part side on the outer peripheral surface of the base part. The described tank.   The tank according to claim 1 or 2, wherein the wall layer of the tank body is formed so that the outer peripheral surface side is harder than the inner peripheral surface side where the part is present.   The tank according to claim 3, wherein the wall layer of the tank main body is gradually hardened from the inner peripheral surface side toward the outer peripheral surface side.   The wall layer of the tank body is composed of resin-containing fibers, and the one portion is softened by increasing the resin content, according to any one of claims 1 to 4. tank. A tank having a cylindrical base portion having a concave portion recessed inwardly on the outer peripheral surface, and a wall layer of a tank body partially entering the concave portion of the base portion,
A tank having elasticity is interposed between the wall layer of the tank body and the recess of the base part. A tank having a cylindrical base portion having a concave portion recessed inwardly on the outer peripheral surface, and a wall layer of a tank body partially entering the concave portion of the base portion,
A tank characterized in that the entire wall layer of the tank body is made of a flexible material.   The tank according to claim 7, wherein the wall layer of the tank body is made of a resin-containing fiber, and a soft resin is used as the resin.