JP4436926B2 - Fuel container for fuel cell - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fuel container for a fuel cell that contains a fuel such as an aqueous methanol solution supplied to a fuel cell such as a polymer electrolyte fuel cell (PEFC).
[0002]
[Prior art]
Conventional containers for storing solutions include, for example, aerosol containers and cosmetic containers. Glass, metal, and plastic are used for the container body. By pressurizing the inside of these containers, when the nozzle is opened, the solution inside flows out in a spray state and is used.
[0003]
In the container as described above, a spring is used as a biasing member that biases the nozzle in the closing direction. As this spring, a metal coil spring is generally used from the viewpoint of cost and convenience, but in order to increase the recycling rate, a structure in which the urging member is made of a resin cylindrical elastic material has been proposed. (For example, refer to Patent Document 1).
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 11-90282
[Problems to be solved by the invention]
By the way, the use of a fuel cell has been examined in various fields, but a fuel container (for example, a fuel cartridge) for supplying fuel to the fuel cell is required. As the fuel, pure water or ethanol is used as methanol. It is practically advantageous to use pure water or pure methanol or pure ethanol.
[0006]
However, particularly in a fuel cell such as a polymer electrolyte fuel cell (PEFC), since mixing of metal ions is extremely disliked, it is necessary to configure the fuel container so that metal ions are not mixed into the contained fuel. found.
[0007]
It is inappropriate to use a metal for the member in contact with the fuel because ions are generated. Even if a resin is coated on the metal, the generation of ions is unavoidable due to the pinhole of the resin film. For this reason, in the present invention, the members constituting the container are made resinous to suppress the generation of metal ions, but at that time, it is most difficult to make the urging member used for the valve mechanism resin. That is, the resin spring has problems in terms of moldability, elastic characteristics, durability, and the like. In particular, when the generated strain becomes large, the resin spring is likely to break, and the durability may be insufficient.
[0008]
The present invention has been made in view of these points, and an object of the present invention is to provide a fuel container for a fuel cell having a structure in which metal ions are not generated while ensuring the durability of the biasing member.
[0009]
[Means for Solving the Problems]
A fuel container for a fuel cell according to the present invention is a fuel container for storing fuel to be supplied to a fuel cell, and includes a container body having a sealed structure, and a valve mechanism for opening and closing the supply of the stored fuel. The constituent members that come into contact with the fuel including the biasing member of the valve mechanism are all made of a non-metallic material.
[0010]
The urging member that urges the valve mechanism actuating member in the closing direction is formed of a resin spring, and the resin spring connects the support base portion that maintains the posture of one end and the abutting portion of the other end. It is preferable to configure with a folded plate spring-like deformed portion. Further, it is preferable that the resin spring is formed so that the cross-sectional shape of the spring element of the plate spring-like deformed portion is larger in width in the direction orthogonal to the thickness along the load application direction.
[0011]
In the fuel container of the present invention, the fuel is methanol and pure water or ethanol and pure water, or pure methanol or pure ethanol, and is suitable for fuel supply of a polymer electrolyte fuel cell. The injection material is injected.
[0012]
【The invention's effect】
According to the present invention as described above, the container body having a sealed structure and the valve mechanism for opening and closing the supply of the stored fuel are provided, and all the constituent members that come into contact with the fuel are made of a non-metallic material. In the fuel cell such as a polymer electrolyte fuel cell (PEFC), metal ions may be present in the supplied fuel such as aqueous methanol solution or aqueous ethanol solution. Although it is extremely disliked, the elution of metal ions can be prevented by demetalization of the above member, and the performance of the fuel cell is not impaired.
[0013]
Further, when the urging member of the valve mechanism is configured by a resin spring including a support base portion that holds the posture of one end, a contact portion at the other end, and a folded plate spring-like deformation portion that connects both, The operation of the valve mechanism can be secured, and it is possible to form a structure that is less likely to break by reducing the occurrence of distortion, and can be made into a resin without problems in terms of durability.
[0014]
Furthermore, if the cross-sectional shape of the spring element of the plate spring-like deformed portion of the resin spring is made wider than the thickness along the load application direction, the stroke length will be short and the occurrence of distortion will be small. It is possible to construct a large resin spring.
[0015]
In addition, the following effects can be obtained with the resinization of the fuel container. The container shape can be formed into various shapes such as a cylindrical shape, a polygonal shape, and an elliptical shape. If a transparent material is used, the contents can be confirmed. Easy to separate and suitable for recycling. When touching the hand, there is no cold like metal, and a warm feeling is good. Changes in contents due to corrosion are unlikely to occur.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail. FIG. 1 is an exploded perspective view of a fuel container for a fuel cell according to one embodiment, and FIG. 2 is a perspective view of a resin spring.
[0017]
A fuel container 1 for a fuel cell according to the present embodiment accommodates methanol and pure water or ethanol and pure water or pure methanol or pure ethanol having a predetermined concentration as fuel for fuel cells, and is contained in a polymer electrolyte fuel cell (PEFC) or the like. For supplying fuel, for example, it is mounted on the fuel cell body as a fuel cartridge. It is also used for refueling in an emergency.
[0018]
The fuel is supplied from the fuel container 1 by a gravity method, a suction method, or an injection method. In this embodiment, the fuel is supplied by an injection method. Injected and contained under pressure.
[0019]
The fuel container 1 includes a container main body 2 that contains fuel, a bottom lid 3 that closes the bottom of the container main body 2, a housing 4 that is mounted on the top of the container main body 2, and a fuel supply port that opens and closes the fuel supply port. The valve mechanism 5 and the dip tube 6 inserted into the container body 2 are configured. And all the parts which comprise these are comprised with a nonmetallic material, ie, resin.
[0020]
The container main body 2 has a substantially cylindrical shape, and reinforcing ribs 21 are installed in the inside so as to connect the inner surfaces of the surrounding side walls to increase the pressure resistance. The bottom opening (not shown) is closed by joining the bottom lid 3, and the top opening 2 a is blocked by joining the lid-like housing 4.
[0021]
At the center of the housing 4, a valve mechanism 5 is installed in a passage that communicates the interior space of the container with the outside. The valve mechanism 5 supplies the fuel stored by opening and closing the passage to a fuel cell (not shown). A dip tube 6 extending from the bottom of the valve mechanism 5 toward the bottom of the container body 2 is attached.
[0022]
The valve mechanism 5 includes a guide screw 51 as a fixing member to the housing 4, a gasket 52 as a valve body for opening and closing fuel supply, a valve stem 53 as an operation member for opening and closing, and a biasing member in a closing direction. The resin spring 54 is used.
[0023]
A resin spring 54 is inserted into the bottom of the passage of the housing 4, a valve stem 53 is inserted thereon, a gasket 52 is fitted on the outer periphery of the valve stem 53, and a guide is provided from above the valve stem 53. The screw 51a of the screw 51 is screwed into the screw hole 41 on the upper surface of the housing 4 and assembled. The valve stem 53 is biased to the upper guide screw 51 by the biasing force of the resin spring 54, and the outer peripheral portion of the gasket 52 is The guide screw 51 is held and fixed to the housing 4.
[0024]
The valve stem 53 has a circumferential groove 53a formed on the outer periphery, a narrow port 53b is opened at the bottom of the circumferential groove 53a and communicates with the central passage 53c, and the central passage 53c opens to the upper end outlet. Note that the bottom of the central passage 53c is closed. A gasket 52 is fitted into the circumferential groove 53 a of the valve stem 53, and the narrow port 53 b is closed by elastic contact of the inner peripheral surface of the gasket 52, so that the inside of the container body 2 and the central passage 53 c of the valve stem 53 are closed. And the fuel supply is blocked. Further, when the valve stem 53 is pushed against the resin spring 54 through the center hole 51b of the guide screw 51, the inner peripheral portion of the gasket 52 is deformed along with the movement to open the narrow port 53b. The fuel is communicated with the inside of the container body 2 and is supplied from the narrow end 53b through the inside of the valve stem 53 through the opening end of the central passage 53c.
[0025]
As shown in FIG. 2, the shape of the resin spring 54 as an urging member is a folded plate spring shape that connects the support base 15 that holds the posture of one end, the abutment portion 16 at the other end, and both. It consists of a deformation part 17. For example, the resin spring 54 is formed of polyacetal (POM).
[0026]
The support base 15 is provided in a plate shape or other shape extending in a direction orthogonal to a compression direction in which a load acts. The abutting portion 16 is formed flat in a plate shape or a bar shape parallel to the support base portion 15, and contacts the bottom portion of the valve stem 53 to transmit an urging force.
[0027]
Further, the leaf spring-like deforming portion 17 is constituted by three slanted spring elements 17a in the case shown in the drawing, and each spring element 17a is sequentially connected in a folded shape by end connecting portions 17b and 17b. . One end of the lowermost spring element 17a is connected and fixed to the end of the support base 15 by the connecting portion 17c, and one end of the uppermost spring element 17a is connected to the one end of the contact portion 16 by the connecting portion 17d. And a resin spring 54 is formed.
[0028]
In addition, the connecting portions 17b, 17c, and 17d at both ends of each spring element 17a are bulged and reinforced so as to increase in thickness, thereby preventing breakage due to distortion during compression deformation. Further, in the cross-sectional shape of each spring element 17a, the width w in the direction orthogonal to the thickness d along the load application direction is larger (w> d). Preferably, w / d is set to about 3 to 4, and the stability of the acting direction of the urging force with respect to the valve stem 53 is secured, and the cross-sectional area of the spring element 17a is large, and the spring constant, that is, the repulsive force of deformation is increased. The repulsive force is 5N or more, the amount of deformation (deflection) for obtaining the required load is reduced, the occurrence of deformation strain is reduced to 5% or less, and the durability to breakage is improved.
[0029]
The resin spring 54 is set such that the ratio of the maximum compression deformation (stroke length) to the free length, that is, the deformation rate is 40% or less (preferably about 32%). That is, the stroke length is set to be short and the amount of distortion is set to be small to further prevent breakage.
[0030]
All the parts of the container body 2, the bottom lid 3, the housing 4 and the valve mechanism 5 that come into contact with the fuel are made of a non-metallic material made of resin to prevent metal ions from being mixed into the fuel. As the resin material, PE, PP, AS, ABS, PAN, PA, PET, PBT, PC, POM, PEN, and the like can be used, and are selected depending on the contents, shape, strength, and the like. For example, considering resistance to methanol, polyethylene (PE), polypropylene (PP), polyethylene naphthalate (PEN), polyethylene terephthalate (PET), and polyacrylonitrile (PAN) are preferable, and acrylonitrile butadiene styrene (ABS), polyamide (PA) and polyacetal (POM) can also be used. Considering the resistance to ethanol, polyethylene (PE), polypropylene (PP), polyamide (PA), polyacetal (POM), polyethylene naphthalate (PEN), polyethylene terephthalate (PET), and polyacrylonitrile (PAN) are excellent. Preferably, acrylonitrile butadiene styrene (ABS) can also be used.
[0031]
As the molding structure, there are a single-layer structure formed of a single material and a two-layer (multi-layer) structure formed of a plurality of materials. In the case of a two-layer structure, a material having excellent resistance is used for the inner layer portion touched by the contents, and a material having excellent pressure resistance and impact resistance is used for the outer layer, and the two-layer molding or coating is used.
[0032]
Moreover, you may provide in the double structure which isolate | separated and accommodated fuels, such as methanol, and an injection material. In this case, only the fuel can be supplied and the fuel does not touch the injection material, so that it is not necessary to consider solubility and emulsification.
[0033]
Moreover, the said container main body 2, the bottom cover 3, and the housing 4 may mutually join each molded article by ultrasonic welding, and airtight assembly property becomes favorable.
[0034]
According to the embodiment as described above, the presence of the metal ions is extremely reduced without the presence of metal ions in the fuel cell fuel such as the aqueous methanol solution or the aqueous ethanol solution due to the resinization of the parts that come into contact with the fuel in the fuel container 1. A good fuel container for the polymer electrolyte fuel cell (PEFC) which is hated can be configured, and the performance of the fuel cell is not impaired.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view of a fuel container for a fuel cell according to one embodiment of the present invention. FIG. 2 is a perspective view of a resin spring.
DESCRIPTION OF SYMBOLS 1 Fuel container for fuel cells 2 Container body 3 Bottom cover 4 Housing 5 Valve mechanism 6 Dip tube
15 Support base
16 Contact part
17 Deformation part
17a Spring element
51 Guide screw
52 Gasket
53 Valve stem
54 Resin spring

Claims (5)

A fuel container for storing fuel to be supplied to a fuel cell, comprising: a container body having a sealed structure; a valve mechanism for opening and closing supply of the stored fuel; and including a biasing member for the container body and the valve mechanism A fuel container for a fuel cell, characterized in that all components that come into contact with fuel are made of a non-metallic material. The urging member that urges the valve mechanism actuating member in the closing direction is formed of a resin spring, and the resin spring connects the support base portion that maintains the posture of one end and the abutting portion of the other end. 2. The fuel container for a fuel cell according to claim 1, wherein the fuel container is constituted by a folded plate spring-like deformed portion. 3. The fuel according to claim 2, wherein the resin spring is formed such that the cross-sectional shape of the spring element of the leaf spring-like deformed portion is larger in width in the direction orthogonal to the thickness along the load application direction. Battery container for batteries. The fuel container for fuel cells according to any one of claims 1 to 3, wherein the fuel is methanol and pure water or ethanol and pure water, and is used for fuel supply of a polymer electrolyte fuel cell. The fuel container for a fuel cell according to any one of claims 1 to 3, wherein the fuel is pure methanol or pure ethanol and is used for supplying fuel to a polymer electrolyte fuel cell.

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