JP2006155954A - Fuel reforming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel reforming device reduced in power generation loss and capable of supplying fuel to a fuel reformer satisfactorily and discharging gas such as a hydrogen gas reformed by the fuel reformer to the outside of the fuel reforming device with safety. <P>SOLUTION: The fuel reforming device comprises: the fuel reformer 9 for generating a reformed gas including a hydrogen gas from fuel; a base body 1; a lid 4; a discharge pipe 5b connecting the inside of a cavity to the outside to discharge the reformed gas from the fuel reformer 9; a supply pipe 5a connecting the inside of the cavity to the outside to supply fuel to the fuel reformer 9; and a lead terminal 2 for power feed that penetrates through the base body 1 or the lid 4. The fuel reformer 9 has a recessed part 9a formed at a portion joined to at least one of the supply pipe 5a and the discharge pipe 5b. The front end of at least one of the supply pipe 5a and the discharge pipe 5b is inserted in the recessed part 9a with a space provided between the side surface of the recessed part 9a and itself, and the front end and the side surface of the recessed part 9a are joined to each other through a joining material 6 filling the space. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a fuel reformer storage container and a fuel reformer for constituting a fuel reformer using a fuel reformer that generates hydrogen gas from various fuels in a fuel cell system, for example.

  In recent years, fuel cell systems have been in the limelight as next-generation power systems that produce electric energy efficiently and cleanly. In the cogeneration power generation system market, which is already represented by the automobile market and household fuel cell power generation systems. In the field, field tests for practical application aiming at low cost are actively conducted.

  More recently, the fuel cell system has been reduced in size and is being studied for use as a power source for portable devices such as mobile phones, PDAs (Personal Digital Assistants), notebook computers, digital video cameras, and digital still cameras.

  In general, a fuel cell uses, for example, hydrocarbon gas such as methane or natural gas (CNG) or alcohol such as methanol or ethanol as fuel, and is converted to hydrogen gas or other gas by a fuel reformer using a fuel reformer. Then, the hydrogen gas is supplied to a power generation device called a power generation cell to generate power.

  The reforming of fuel by the fuel reformer here refers to a process of generating hydrogen gas by a catalytic reaction.

For example, when methanol is used as the fuel, there are several reactions for reforming the fuel. For example, in the steam reforming reaction shown in the following chemical reaction formula (1) (in formula (1), steam is added to methanol. This is a process for generating hydrogen gas (H ₂ ) by combining them with a reaction to reform hydrogen and carbon dioxide. Note that a very small amount of product gas (mainly CO ₂ ) other than hydrogen produced by this reforming reaction is usually discharged into the atmosphere.

CH ₃ OH + H ₂ O → 3H ₂ + CO ₂ (1)
Since such a steam reforming reaction is an endothermic reaction, it is necessary to maintain the reaction temperature by heating from the outside with a heater or the like. Therefore, in order to reform the fuel in the fuel reformer, for example, methanol was used as the fuel in order to prevent the steam reforming activity of the catalyst from being lowered and to maintain a high concentration of generated hydrogen gas. In some cases, a temperature of about 200 to 500 ° C. is required, and in the case of using methane gas, a high temperature of about 300 to 800 ° C. is required.

  For example, in the partial oxidation reforming reaction as shown in the following chemical reaction formula (2), a reforming temperature of about 400 to 600 ° C. is required.

CH ₃ OH + 1 / 2O ₂ + 2N ₂ → 2H ₂ + CO ₂ + 2N ₂ (2)
Therefore, in a cogeneration power generation system typified by a household fuel cell system, since this system itself is large, the outer wall of the fuel reformer storage container is made into a double structure to form a vacuum container, or 2 By filling a heat insulating material between the inner and outer walls having a heavy structure, the heat inside the fuel reformer is prevented from being conducted to the outside and the temperature of the fuel reformer is lowered. Therefore, when storing the fuel reformer in the fuel reformer storage container, the fuel reformer can be directly mounted and fixed on the inner wall of the double structure of the fuel reformer storage container. It is.
JP 2003-2602 A

  In recent years, fuel cell systems for portable devices have been required to be reduced in size and height for storage in portable devices. However, the conventional structure of the outer wall of the fuel reformer storage container having a double structure cannot be employed in a fuel cell system for portable devices because the entire fuel cell system becomes complicated and large. . Therefore, in a fuel cell system for portable equipment, when reforming fuel in the fuel reformer by evacuating the inside of the container for housing the fuel reformer composed of a base body having a cavity and a lid. It has been proposed to provide a fuel cell system that cuts off heat generated to the outside and reduces power generation loss.

  In order to use such a fuel cell system stably and safely for a long period of time, the fuel reformer storage container is sealed with the fuel reformer stored in the vacuum state inside the fuel reformer storage container. It is necessary to keep it not only immediately but also for a long time thereafter. However, since the joint area between the supply pipe and discharge pipe and the fuel reformer is reduced for the purpose of suppressing heat transfer from the fuel reformer, the strength of this joint is particularly weakened and the supply pipe and discharge are reduced. Stress tends to concentrate on the brazing material joining the pipe and the fuel reformer, and cracking occurs in the brazing material between the supply pipe and discharge pipe and the fuel reformer when a long-term heat cycle test is performed. Gas or reformed gas leaks, resulting in poor airtightness. Therefore, since the degree of vacuum inside the fuel reformer storage container decreases, the amount of heat generated when reforming the fuel in the fuel reformer increases to the outside. Due to the heat, the fuel reformer storage container becomes hot, and there is a problem that other parts in the portable device are destroyed and there is a high possibility that the user of the portable device will be burned.

  In the case where the fuel reforming reaction is an endothermic reaction such as the steam reforming reaction of the chemical reaction formula (1), the fuel reformer is heated with a heater or the like in order to reform the fuel with the fuel reformer. Although it is necessary to maintain the reaction temperature at a constant temperature, the heat of the fuel reformer is conducted to the fuel reformer storage container as described above, so that the temperature of the fuel reformer decreases. It becomes easy to do.

  Therefore, in order to maintain the reaction temperature, it is necessary to increase the heat generation amount of the heater. However, if the heat generation amount of the heater is increased, the electricity used for heating the heater in the total electric capacity generated by the power generation cells of the fuel cell. As a result, the capacity increases, and as a result, the power generation loss of the entire fuel cell system increases.

  The present invention has been completed in view of the above-described problems in the prior art, and its purpose is to supply fuel to the fuel reformer satisfactorily, as well as hydrogen gas reformed by the fuel reformer, etc. It is an object of the present invention to provide a fuel reforming apparatus that can safely discharge the gas out of the fuel reforming apparatus and reduce power generation loss.

  The fuel reformer of the present invention closes a fuel reformer that generates reformed gas containing hydrogen gas from fuel, a base body having a cavity in which the fuel reformer is housed, and an opening of the cavity. In this way, the lid attached to the upper surface of the base body, a discharge pipe communicating between the inside of the cavity and the outside to discharge the reformed gas from the fuel reformer, and the fuel reformer In the fuel reformer comprising a supply pipe that communicates the inside of the cavity and the outside to supply the fuel, and a power supply lead terminal that penetrates the base body or the lid, the fuel reformer includes the fuel reformer, A recess is formed in a joint portion between at least one of the supply pipe and the discharge pipe, and at least one tip of the supply pipe and the discharge pipe is fitted into the recess with a gap from a side surface of the recess. And fill the gap And the tip portion through the by bonding material and the concave side surface, characterized in that it is joined.

  In the fuel reforming apparatus of the present invention, preferably, at least one of the supply pipe and the discharge pipe fitted in the recess has a tip end pointed over the entire circumference.

  In the fuel reformer of the present invention, a recess is formed at a joint portion between at least one of the supply pipe and the discharge pipe of the fuel reformer, and at least one tip of the supply pipe and the discharge pipe is formed in the recess. Since the tip and the side surface of the recess are joined to each other through the bonding material filled in the gap while being fitted with the side surface of the recess, between the outer surface of the supply pipe and the discharge pipe and the side surface of the recess. A sufficient amount of bonding material can be stored, and the connection between the fuel reformer and the supply pipe and the discharge pipe becomes three-dimensional and extremely strong. Therefore, it is possible to maintain good airtightness in the fuel reformer not only immediately after the fuel reformer is accommodated in the fuel reformer but also thereafter.

  As a result, the fuel reformer can be insulated to suppress the temperature drop of the fuel reformer, and a large amount of electric power is supplied to the heater to maintain the temperature necessary for operating the fuel reformer well. There is no need to continue, and the power generation efficiency can be improved.

  In addition, since the airtightness in the fuel reformer apparatus can be maintained well and the heat insulation can be improved, it is possible to effectively prevent the heat of the fuel reformer from being transferred to the outer wall of the fuel reformer. In addition, the fuel cell system can be used stably and safely for a long period of time, which can effectively prevent other parts in the portable device from being destroyed or burned to the user of the portable device.

  In the fuel reformer of the present invention, since at least one of the supply pipe and the discharge pipe fitted in the recess has a pointed end surface over the entire circumference, the fuel reformer is joined to the supply pipe and the discharge pipe. Since the area is reduced and heat conduction from the fuel reformer to the base and lid via the supply pipe and discharge pipe can be greatly reduced, the temperature of the outer wall surface of the fuel reformer rises. It can be effectively suppressed.

  As a result, the temperature drop of the fuel reformer can be more effectively suppressed, and the power generation efficiency can be significantly improved.

  Embodiments of the fuel reformer of the present invention will be described in detail below.

  FIG. 1 is a sectional view showing an example of an embodiment of a fuel reformer of the present invention. FIG. 2 is an enlarged cross-sectional view of a main part of a joint portion between a supply pipe or a discharge pipe and a fuel reformer in the fuel reformer of FIG. In these drawings, 1 is a base, 2 is a lead terminal as wiring for supplying power to the fuel reformer, 3 is a bonding wire, 4 is a lid, and 5a is for supplying fuel to the fuel reformer. , 5b is a discharge pipe for discharging the reformed gas from the fuel reformer, 6 is a bonding material for joining the supply pipe 5a or the discharge pipe 5b and the fuel reformer 9, and 7 is an electrode, 8 is an insulating sealing material for insulating and fixing the lead terminal 2 in the through hole of the base 1, 9 is a fuel reformer, and 9 a is a recess provided in the fuel reformer 9. The base body 1, the cover body 4, the supply pipe 5a and the discharge pipe 5b constitute a fuel reformer storage container for storing the fuel reformer 9, and the fuel reformer is stored in the fuel reformer storage container. Thus, the fuel reformer 11 is obtained.

Both the base body 1 and the lid body 4 in the present invention have a role as a container for storing the fuel reformer 9. These include, for example, Fe-based alloys such as SUS, Fe—Ni—Co alloys, Fe—Ni alloys, oxygen-free copper metal materials, aluminum oxide (Al ₂ O ₃ ) -based sintered bodies, mullite (3Al ₂ Ceramic materials such as O ₃ .2SiO ₂ ) sintered body, silicon carbide (SiC) sintered body, aluminum nitride (AlN) sintered body, silicon nitride (Si ₃ N ₄ ) sintered body, and glass ceramics Further, it is made of a highly heat-resistant resin material such as polyimide.

The glass ceramics applicable to the substrate 1 and the lid 4 are composed of a glass component and a filler component. As the glass component, for example, SiO ₂ —B ₂ O ₃ system, SiO ₂ —B ₂ O ₃ —Al ₂ O ₃ system, SiO ₂ —B ₂ O ₃ —Al ₂ O ₃ —MO system (where M is Ca, Sr, Mg, Ba or Zn), SiO ₂ —Al ₂ O ₃ —M ¹ O—M ² O system (where M ¹ and M ² are the same or different and Ca, Sr, Mg, Ba or Zn), SiO ₂ —B ₂ O ₃ —Al ₂ O ₃ —M ¹ O—M ² O system (where M ¹ and M ² are the same as above), SiO ₂ —B ₂ O ₃ — M ³ ₂ O system (where M ³ represents Li, Na or K), SiO ₂ —B ₂ O ₃ —Al ₂ O ₃ —M ³ ₂ O system (where M ³ is the same as above) , Pb glass, Bi glass and the like.

Examples of the filler component include a composite oxide of Al ₂ O ₃ , SiO ₂ , ZrO ₂ and an alkaline earth metal oxide, a composite oxide of TiO ₂ and an alkaline earth metal oxide, Al ₂ O _3. And composite oxides containing at least one selected from SiO ₂ (for example, spinel, mullite, cordierite) and the like.

  On the other hand, when the base 1 and the lid 4 are formed of a dense aluminum oxide sintered body having a relative density of 95% or more, for example, first, rare earth oxide powder or aluminum oxide powder is added to the aluminum oxide powder. A raw material powder of an aluminum oxide sintered body is prepared by adding and mixing a sintering aid such as the above. Next, an organic binder and a dispersion medium are added to the raw material powder, mixed to form a paste, and this paste is green by a doctor blade method, or an organic binder is added to the raw material powder, press forming, rolling forming, etc. A sheet is produced. Then, after aligning a predetermined number of sheet-like molded bodies and laminating and pressure-bonding, the laminated body is fired at a firing maximum temperature of 1200 to 1500 ° C., for example, in a non-oxidizing atmosphere, and the target ceramic A base body 1 and a lid 4 made of the product are obtained. The base 1 and the lid 4 may be molded by a powder molding press method.

  On the other hand, when the base 1 and the lid 4 are made of a metal material, they are formed into a predetermined shape by a cutting method, a press method, a MIM (Metal Injection Mold) method, or the like.

  Further, when the base 1 and the lid 4 are made of a metal material, the surface thereof is subjected to a coating treatment such as Au or Ni plating or a resin coating such as polyimide in order to prevent corrosion. Is desirable. For example, in the case of Au plating treatment, the thickness is desirably about 0.1 to 5 μm.

  Further, by covering at least the inner surface of the fuel reformer storage container constituted by the base body 1 and the lid body 4 with an Au or Al plating film, the radiant heat generated in the accommodated fuel reformer 9 is efficiently generated. This can be prevented well, and the temperature rise of the fuel reformer 11 can be suppressed.

  The base 1 and the lid 4 as described above should be reduced in thickness in order to enable the fuel reformer 11 to be reduced in size and height, but the bending strength, which is mechanical strength, is 200 MPa. The above is preferable.

  Next, the lead terminal 2 in the present invention is preferably made of a metal having the same or approximate thermal expansion coefficient as that of the base body 1 and the lid body 4, for example, made of Fe—Ni alloy or Fe—Ni—Co alloy. However, it is possible to prevent the occurrence of thermal strain with respect to temperature changes during practical use. In addition, a good sealing property between the lead terminal 2 and the substrate 1 can be obtained, the bonding property is excellent, and the strength necessary for mounting and good solderability and weldability can be secured.

  The insulating sealing material 8 of the present invention is made of, for example, a glass material such as borosilicate glass, alkali glass, or insulating glass mainly containing lead, or a ceramic material such as aluminum oxide. The base 1 and the lead terminals 2 are electrically insulated by the insulating sealing material 8 in the through holes, and the lead terminals 2 are sealed and fixed. The through-hole through which the lead terminal 2 formed in the base body 1 is inserted needs to have a size such that the base body 1 and the lead terminal 2 do not come into electrical contact with each other. An inner diameter that can ensure a distance of 0.1 mm or more from the base 1 to the base 1 is required.

  When the insulating sealing material 8 is made of a ceramic material such as aluminum oxide, the lead terminal 2 is inserted into the through hole of the base 1 through the insulating sealing material 8 made of, for example, a cylindrical ceramic material, and the insulating sealing material 8 is sealed. The connection between the stopper 8 and the substrate 1 and the connection between the insulating sealing material 8 and the lead terminal 2 can be made with a brazing material such as Au—Ge or Ag—Cu.

  The electrode 7 on the fuel reformer 9 and the lead terminal 2 are electrically connected via the bonding wire 3. Further, by sealing the cavity of the base body 1 using the lid 4, the fuel reformer 11 is formed in which the fuel reformer 9 accommodated in the cavity of the fuel reformer storage container is hermetically sealed. The

  The fuel reformer 9 accommodated in the fuel reforming apparatus 11 of the present invention is an apparatus for reforming fuel, and a fine flow path or void in which a catalyst for reforming the fuel is supported. Have

  The shape of the fuel reformer 9 is various. For example, as a fine chemical device, by applying a semiconductor manufacturing technology or the like, for example, a semiconductor such as silicon, a substrate of an inorganic material such as quartz, glass, metal, ceramics, A liquid flow path is created by forming a narrow groove by a cutting method, etching method, blasting method, etc., and for the purpose of preventing evaporation of the liquid during operation, a glass plate, a metal cover, etc. are anodic bonded, brazed, For example, a substantially rectangular shape is used which is used in close contact with the surface by welding or the like. Moreover, it is a tube made of an inorganic material such as quartz, glass, metal, ceramics, etc., and the inner surface of which is supported with a catalyst for reforming the fuel.

  When the fuel reforming reaction is an endothermic reaction such as a steam reforming reaction, the fuel reformer 9 has a temperature control mechanism, for example, a thin film heater (not shown) or a thick film heater (not shown) composed of a resistance layer or the like. The electrode 7 is formed on the surface as a terminal for supplying power to the heater. By adjusting the temperature condition to about 200 to 800 ° C. corresponding to the fuel reforming condition by this temperature adjusting mechanism, the fuel supplied from the fuel supply port to which the supply pipe 5a is connected is caused to react with the water vapor. The reforming reaction for generating hydrogen gas from the discharge pipe 5b connected to the discharge port can be favorably promoted.

  Such a heater is disposed in or near the flow path, the gap, or the like where the catalyst in the fuel reformer 9 is supported and reforms the fuel. By doing so, the heat generated from the heater can be efficiently used for the fuel reforming reaction.

  Further, the fuel reformer 9 has a concave portion 9a having an inner dimension larger than the outer dimension of the front end surface of the supply pipe 5a or the discharge pipe 5b at the joint between the fuel reformer 9 and the supply pipe 5a or the discharge pipe 5b. Is formed. A supply port for supplying fuel into the fuel reformer 9 or a discharge port for discharging the reformed gas from the fuel reformer 9 is formed on the bottom surface of the recess 9a. And the front-end | tip part of the supply pipe | tube 5a and the discharge pipe 5b is joined via the joining material so that it may be fitted in the recessed part 9a and it may connect with the supply port and discharge port formed in the bottom face of the recessed part 9a. At this time, a gap between the outer surface of the supply pipe 5a and the discharge pipe 5b and the side surface of the recess 9a becomes a pool portion for the bonding material.

  The size of the concave portion 9a is set to a size necessary for securing a pool portion of the bonding material between the side surface of the concave portion 9a and the outer surface of the supply pipe 5a and the discharge pipe 5b. Specifically, the distance from the outer surface of the tip of the supply pipe 5a or the discharge pipe 5b to the side surface of the recess 9a of the fuel reformer 9 is preferably 30 μm or more and 2 mm or less, and the depth of the recess 9a is 30 μm or more and 2 mm or less. It is preferable.

  When the distance from the outer surface of the front end of the supply pipe 5a or the discharge pipe 5b to the side surface of the recess 9a of the fuel reformer 9 is less than 30 μm, the side surface of the recess 9a of the fuel reformer 9 and the supply pipe 5a opposite to the side surface. And the volume of the space formed between the outer surface of the distal end portion of the discharge pipe 5b is reduced, and a sufficient reservoir for the bonding material 6 cannot be formed, and the supply pipe 5a and the discharge pipe 5b are connected to the fuel reformer 9. There is a tendency that it is difficult to firmly join the fuel reformer 9 provided with the recess 9a. On the other hand, if it exceeds 2 mm, the volume of the space formed between the side surface of the concave portion 9a of the fuel reformer 9 and the outer surface of the front end portion of the supply pipe 5a and the discharge pipe 5b facing this becomes too large. There is a tendency that the joining material 6 cannot be completely filled therein and it becomes difficult to firmly join the supply pipe 5 a and the discharge pipe 5 b to the fuel reformer 9.

  Further, when the depth of the concave portion 9a of the fuel reformer is less than 30 μm, it is formed between the side surface of the concave portion 9a of the fuel reformer and the outer surface of the front end portion of the supply pipe 5a and the discharge pipe 5b facing this. The volume of the space to be formed becomes small, and a sufficient reservoir for the joining material 6 cannot be formed, so that it is difficult to firmly join the supply pipe 5a and the discharge pipe 5b to the fuel reformer 9. On the other hand, if it exceeds 2 mm, the volume of the space formed between the side surface of the concave portion 9a of the fuel reformer 9 and the outer surface of the front end portion of the supply pipe 5a and the discharge pipe 5b facing this becomes too large. It is difficult to completely fill the bonding material 6 in the interior, so that a sufficient reservoir of the bonding material 6 cannot be formed, and it is difficult to firmly bond the supply pipe 5a and the discharge pipe 5b to the fuel reformer 9. Tend to be.

  For joining the supply port and the discharge port of the fuel reformer 9 to the supply pipe 5a and the discharge pipe 5b, various brazing materials such as an Au—Sn alloy, an Au—Si alloy, an Au—Ge alloy, and an Ag—Cu alloy are used. Materials, quartz glass, borosilicate glass, etc., various ceramics, inorganic adhesives containing inorganic polymers, adhesives containing high heat-resistant organic materials such as polyimide amide, adhesives composed of organosilicon compounds such as silicone rubber and silicon resin A bonding material such as an agent can be applied, thereby effectively preventing leakage of fuel gas and exhaust gas, and the inside of the fuel reforming apparatus 11 can be well maintained for a long time.

  The fuel reformer 9 has a cover 4 attached by covering the cavity to the substrate 1 by joining with a metal brazing material such as an Au alloy, an Ag alloy, an Al alloy, or a glass material, or by a seam weld method. The fuel is reformed in the fuel reformer 11.

  For example, in the case of joining with an Au—Sn brazing material, an Au—Sn brazing material formed by welding a Au—Sn brazing material to the lid 4 in advance or punching using a die or the like is used. After the material is placed between the base body 1 and the lid body 4, the lid body 4 is joined to the base body 1 by a sealing furnace or a seam welder, so that the fuel reformer 9 is installed inside the fuel reformer 11. It can be sealed.

  In the fuel reformer 9, the electrode 7 on the fuel reformer 9 is electrically connected to the lead terminal 2 provided on the substrate 1 through the bonding wire 3. Thereby, the heater formed on the surface or inside of the fuel reformer 9 can be heated through the electrode 7. As a result, the reaction temperature can be maintained in the fuel reformer 9, and the fuel reforming reaction can be stabilized.

The supply pipe 5a and the discharge pipe 5b are a supply path for raw materials and fuel gas fluid and a discharge path for reformed gas containing hydrogen, respectively. These include, for example, SUS-based metal material, Fe-Ni alloy, Fe-Ni-Co alloy, _Al 2 _{O 3} sintered _material, 3Al ₂ O 3 · 2SiO ₂ sintered material, SiC sintered material, AlN It is made of a ceramic material such as a sintered material, a Si ₃ N ₄ material, a glass ceramic sintered material, a highly heat resistant resin material such as polyimide, or glass.

  Preferably, it is difficult to be embrittled by hydrogen contained in the reformed gas. Such materials include Fe alloys, ceramics, and glass.

  Further, it is preferable that at least one of the supply pipe 5a and the discharge pipe 5b has a pointed end surface over the entire circumference as shown in FIG. Thereby, the joint area between the fuel reformer 9 and the supply pipe 5a and the discharge pipe 5b is reduced, and heat is transferred from the fuel reformer 9 to the base body 1 and the lid body 4 via the supply pipe 5a and the discharge pipe 5b. Since conduction can be greatly reduced, it is possible to effectively suppress the temperature of the outer wall surface of the fuel reformer 11 from rising.

  The front end surfaces of the supply pipe 5a and the discharge pipe 5b may be pointed so that the outer surface side protrudes as shown in FIG. 3, or may be pointed so that the inner surface side protrudes. Moreover, you may sharpen between an inner surface and an outer surface.

  The fuel pipe 5a and the discharge pipe 5b are inserted into through holes formed in the base body 1 or around the through holes inside the base body 1 with the supply pipe 5a and the discharge pipe 5b of the base body 1 divided. And it joins so that a through hole may be inserted | pinched around the through hole of the base | substrate 1 outer side. As this joining method, depending on the material constituting the supply pipe 5a, the discharge pipe 5b, and the substrate 1, ultrasonic joining, thermal welding, pressure bonding, adhesion with a resin adhesive, or a brazing material such as Au—Si or Ag—Cu is used. Various methods such as bonding, bonding with glass such as borosilicate glass, and simultaneous sintering are appropriately used.

  The inner diameters of the supply pipe 5a and the discharge pipe 5b are preferably set to φ0.1 mm or more so as to suppress the pressure loss of the fluid and to be φ5 mm or less for miniaturization and low profile.

  The cross-sectional shape of the joint portion between the supply pipe 5a and the discharge pipe 5b may be generally circular, but is not limited thereto. That is, besides the circular shape, there are an elliptical shape and a rectangular shape whose side can be aligned with the fluid flow direction, for example, a square shape and a rectangular shape. Further, the thickness needs to be a thickness that does not deform due to the pressure of the raw material supply or reaction gas discharge. When the material is made of the above-mentioned materials, it is usually 0.1 mm or more when used for a portable device or the like. Further, the length in the flow direction is preferably as long as possible to make it difficult for heat generated in the fuel reformer 9 to be transmitted to the power generation cell, but it should be taken into consideration in consideration of the size of the entire fuel cell system.

  Further, in order to obtain the heat insulation in the fuel reformer 11, it is necessary to make the inside of the fuel reformer 11 vacuum, and when sealing the fuel reformer 9, it is caused by brazing material in a vacuum furnace. What is necessary is just to carry out by the seam weld method etc. in sealing or a vacuum chamber.

  In addition, the supply pipe 5a and the discharge pipe 5b are preferably formed with a plurality of grooves parallel to the axial direction or a plurality of grooves perpendicular to the axial direction on the outer surface of the portion inside the fuel reformer 11. As a result, the heat conduction of the supply pipe 5a and the discharge pipe 5b can be reduced to more effectively suppress the heat conduction from the fuel reformer 9 to the base body 1 and the lid body 4, and the supply pipe 5a and the discharge pipe 5b can be appropriately controlled. And the stress can be relieved by appropriate deformation of the supply pipe 5a and the discharge pipe 5b, the joint between the supply pipe 5a and the discharge pipe 5b and the fuel reformer 9, and the supply pipe It is possible to maintain the bonding of the bonding portion between the base 5 or the discharge pipe 5b and the base body 1 or the lid body 4 well.

  In addition, this invention is not limited to the example of the above embodiment, A various change may be added in the range which does not deviate from the summary of this invention. For example, in the example shown in FIG. 1, the fuel pipe 5 a and the discharge pipe 5 b are joined to the lower surface of the fuel reformer 9, but these are joined to the upper surface according to the specifications of the fuel reformer 9. Also good. A plurality of supply pipes 5a and discharge pipes 5b may be formed.

It is sectional drawing which shows an example of embodiment of the fuel reforming apparatus of this invention. FIG. 2 is an enlarged cross-sectional view of a main part of a joint portion between a supply pipe or a discharge pipe and a fuel reformer in the fuel reformer of FIG. 1. It is a principal part expanded sectional view of the junction part of the supply pipe or discharge pipe and fuel reformer in other examples of the embodiment of the fuel reformer of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Base | substrate 4 ... Lid body 5a ... Supply pipe 5b ... Discharge pipe 6 ... Brazing material 9 ... Fuel reformer 9a ... ..Recess 11 ... Fuel reformer device

Claims (2)

A fuel reformer that generates reformed gas including hydrogen gas from the fuel, a base body having a cavity in which the fuel reformer is housed, and an upper surface of the base body so as to close the opening of the cavity. An attached lid, a discharge pipe communicating the inside of the cavity with the outside to discharge the reformed gas from the fuel reformer, and the inside of the cavity to supply the fuel to the fuel reformer The fuel reformer comprises a supply pipe that communicates with the outside and a lead terminal for power feeding that penetrates the base body or the lid, and the fuel reformer is at least one of the supply pipe and the discharge pipe A joint is formed in which a tip of at least one of the supply pipe and the discharge pipe is fitted in a gap with a side surface of the recess and is filled in the gap. Before The fuel reforming apparatus characterized by the tip and the recess side are joined. 2. The fuel reformer according to claim 1, wherein at least one of the supply pipe and the discharge pipe fitted in the concave portion has a tip end pointed over the entire circumference.

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