JP2013065449A - Fuel cell device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel cell device that allows a fuel gas tank to be fixed without boring a hole in a casing.SOLUTION: A fuel cell device generates electricity by means of fuel gas and oxidant gas, and includes: a fuel cell assembly 12 that has a plurality of electrically connected fuel cells and generates electricity from a reaction between the fuel gas and the oxidant gas in the fuel cells; a fuel gas tank 68 that is placed below the fuel cell assembly 12 and distributes and supplies the fuel gas to the fuel cells; a casing 56 that houses the fuel cell assembly 12 and the fuel gas tank 68 and is formed in such a manner that the interior thereof is a sealed space; and a fixing member 30 that fixes the fuel gas tank 68 to the casing 56. The fixing member 30 has: a welded portion 31 that is fixed by welding to the casing 56; a coupling portion 32 that is coupled to the welded portion 31; and a bolt fixing portion 33 that is fixed by welding to the fuel gas tank 68 and fixes the coupling portion 32 with a bolt 34.

Description

  The present invention relates to a fuel cell device that generates power using a fuel gas and an oxidant gas.

  A plurality of single cells capable of obtaining electric power using fuel gas (hydrogen-containing gas) and air (oxygen-containing gas, oxidant gas) are accommodated in the casing, and fuel gas and air are stored in the plurality of single cells. Various fuel cell devices that generate electricity by supplying power are proposed. In such a fuel cell device, when a manifold such as a fuel gas tank is fixed to the casing, a bolt fixing hole is formed in the casing and the bolt is fixed. The bolt fixing hole is sealed with a seal member in order to maintain airtightness in the casing. In Patent Document 1 below, when the gas tank (6) shown in FIG. 10 is fixed to the casing, a hole is formed in the casing, and the U-shaped fixing portion protruding from the end of the gas tank and the casing are bolted. Become.

JP 2011-54478 A

  The internal temperature of the fuel cell device rises from 600 degrees to nearly 1000 degrees due to heat generated during power generation. Therefore, in the fuel cell device, the temperature difference between the start time and the stop time becomes large. In the fuel cell device in which such a temperature difference occurs, even if the bolt fixing hole is tightly sealed with the seal member, the seal member is likely to deteriorate due to temperature fluctuation. If the seal member deteriorates, it becomes difficult to maintain the airtightness in the casing, and the air in the casing may leak to the outside. If air leaks to the outside, the heat of the internal air and the air itself may not be used effectively. Further, since the inside of the casing during power generation becomes hot and humid, if the hot and humid air leaks outside the casing, the heat insulating material is likely to deteriorate. When the heat insulating material deteriorates, heat dissipation increases, and it becomes difficult to maintain the internal temperature of the fuel cell device at an appropriate temperature, which may reduce power generation performance.

  The present invention has been made in view of such a problem, and an object of the present invention is a fuel cell device that generates power using fuel gas and oxidant gas, and has a hole in the casing when the gas manifold is fixed to the casing. An object of the present invention is to provide a fuel cell device that can be fixed without opening.

  In order to solve the above-mentioned problems, a fuel cell device according to the present invention is a fuel cell device that generates electric power using fuel gas and oxidant gas, and has a plurality of electrically connected fuel cells, and the fuel cell device A fuel cell assembly that generates power by reacting a fuel gas and an oxidant gas in a battery cell, and a fuel cell that is disposed below the fuel cell assembly and distributes and supplies the fuel gas to the fuel cell A gas manifold, a casing configured to house the fuel cell assembly and the gas manifold and configured to be a sealed space inside, and a fixing member that fixes the gas manifold to the casing are provided. . The fixing member includes a welded portion fixed to the casing by welding, a connecting portion connected to the welded portion, and a bolt fixing portion fixed to the gas manifold by welding and fixing the connecting portion with a bolt. .

  In the present invention, the connecting portion connected to the welded portion welded and fixed to the casing can be bolted to the bolted fixed portion welded to the gas manifold. Thereby, a gas manifold can be fixed to a casing, without making a hole in a casing. That is, by using the configuration of the present invention, it is possible to firmly fix the gas manifold to the casing while ensuring airtightness in the casing.

  Further, in the fuel cell device according to the present invention, when the mounting surface of the casing on which the fixing member is mounted is used as a reference, the height of the welded portion is lower than the height of the connecting portion. It is also preferable.

  In this preferable aspect, since the thickness of the welded portion of the fixing member can be reduced, spot welding that can suppress the deformation of the casing as much as possible by suppressing the area to be welded at a high temperature as the welded portion is employed. Is possible. On the other hand, since the connection part of a fixing member can be made higher than the height of a welding part, the board | plate thickness required in order to fix firmly with a bolt fixing | fixed part can be ensured. As a result, the thickness of the casing can be reduced to reduce the weight of the fuel cell device, while ensuring airtightness in the casing, and the gas manifold can be firmly fixed to the casing.

  Further, in the fuel cell device according to the present invention, it is preferable that the connecting portion includes a substantially reverse concave strain permitting portion that suppresses transmission of strain force generated in the bolt fixing portion to the welded portion.

  In this preferred embodiment, by providing a substantially reverse concave strain allowing portion, it is possible to suppress the strain force generated in the bolt fixing portion from being transmitted to the welded portion. For example, the gas manifold expands due to heat during power generation. Even when a strain force is generated in the bolt fixing portion, the strain force can be absorbed by the strain allowing portion, so that the strain force can be suppressed from being transmitted to the welded portion. Thereby, the welding fixation by a welding part can be protected from a distortion force.

  Moreover, the fuel cell apparatus which concerns on this invention WHEREIN: It is also preferable that the said connection part contains the stopper part which restrict | limits the deformation | transformation by the distortion | strain of the said distortion | strain tolerance part by contacting with the mounting surface mentioned above.

  In this preferred embodiment, even when the strain allowable portion is deformed due to strain, the stopper portion can limit the deformation, so that the deformation can be limited within a range in which the strain allowable portion is not damaged. It becomes possible to reinforce the decreasing vertical support force.

  Further, in the fuel cell device according to the present invention, the connecting portion further includes a substantially L-shaped L-shaped portion, and the L-shaped portion allows strain in a direction substantially orthogonal to the strain allowable direction of the strain allowable portion. And it is also preferable that the said bolt fixing | fixed part is fixed with the said L-shaped part and a volt | bolt, and provides a clearance gap between the said fixing member except the said bolt fixing | fixed part, and the said gas manifold.

  In this preferred embodiment, a clearance is provided between the fixing member and the gas manifold, and by providing an L-shaped portion, in addition to the strain allowable direction by the strain allowable portion, strain in a direction substantially orthogonal to the strain allowable direction is also allowed. can do. As a result, even when multi-directional strain force is generated in the bolt fixing portion, the strain force can be absorbed by both the strain allowing portion and the L-shaped portion. Transmission can be further suppressed.

  According to the present invention, there is provided a fuel cell device that generates power using a fuel gas and an oxidant gas, and can fix a gas manifold without making a hole when the gas manifold is fixed to the casing. can do.

It is a perspective view which shows the external appearance of the fuel cell module in embodiment of this invention. It is sectional drawing in the center vicinity of FIG. 1, Comprising: It is sectional drawing which shows the cross section seen from the A direction of FIG. It is sectional drawing in the center vicinity of FIG. 1, Comprising: It is sectional drawing which shows the cross section seen from the B direction of FIG. It is a perspective view which shows the state which removed some outer plates from the casing of FIG. FIG. 3 is a schematic diagram corresponding to FIG. 2, and is a schematic diagram showing flows of power generation air and combustion gas. FIG. 4 is a schematic diagram corresponding to FIG. 3, and is a schematic diagram showing flows of power generation air and combustion gas. It is a fragmentary sectional view which shows the fuel cell unit used for this embodiment. It is a perspective view which shows the structure of the fuel cell stack in this embodiment. FIG. 5 is a cross-sectional view in the vicinity of a fixing member of the fuel cell module of FIG. 4, and is a partial cross-sectional view seen from the direction A of FIG. 4. It is a fragmentary perspective view at the time of seeing a part of fixing member shown in FIG. 9 from the upper side on the opposite side to a fuel gas tank. FIG. 10 is a partial perspective view when a part of the fixing member shown in FIG. 9 is viewed from above on the fuel gas tank side. (A) is a schematic diagram showing the vicinity of the fixing member when the fuel cell module is stopped, and (B) is a schematic diagram showing the vicinity of the fixing member when the fuel cell module is operating. (A) is a schematic diagram showing a fixing member when the fuel cell module is stopped, and (B) is a schematic diagram showing the fixing member when the fuel cell module is operating. It is a figure which shows the modification of the fixing member shown in FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In order to facilitate the understanding of the description, the same constituent elements in the drawings will be denoted by the same reference numerals as much as possible, and redundant description will be omitted.

  A fuel cell module (fuel cell device) according to an embodiment of the present invention will be described with reference to FIG. A fuel cell module 2 shown in FIG. 1 constitutes a part of a solid oxide fuel cell device. The solid oxide fuel cell device includes a fuel cell module 2 and an auxiliary unit (not shown).

  In FIG. 1, the height direction of the fuel cell module 2 is the y-axis direction. The x axis and the z axis are defined along a plane perpendicular to the y axis, the direction along the short direction of the fuel cell module 2 is defined as the x axis direction, and the direction along the longitudinal direction of the fuel cell module 2 is defined as z. Axial direction. The x-axis, y-axis, and z-axis described in FIG. 2 and thereafter are based on the x-axis, y-axis, and z-axis in FIG. Further, the direction along the negative direction of the z axis is the A direction, and the direction along the positive direction of the x axis is the B direction.

  The fuel cell module 2 includes a casing 56 that houses fuel cells (details will be described later), and a heat exchanger 22 that is provided on the upper portion of the casing 56. The inside of the casing 56 is a sealed space. A reformed gas supply pipe 60 and a water supply pipe 62 are connected to the casing 56. On the other hand, a power generation air introduction pipe 74 and a combustion gas discharge pipe 82 are connected to the heat exchanger 22.

  The to-be-reformed gas supply pipe 60 is a pipe line that supplies a to-be-reformed gas for reforming such as city gas into the casing 56. The water supply pipe 62 is a pipe for supplying water used when steam reforming the gas to be reformed. The power generation air introduction pipe 74 is a pipe for supplying power generation air (oxidant gas) for causing a power generation reaction with the reformed fuel gas. The combustion gas discharge pipe 82 is a pipe line for discharging the combustion gas generated as a result of burning the fuel gas after the power generation reaction.

  Next, the inside of the fuel cell module 2 will be described with reference to FIGS. 2 is a cross-sectional view of the fuel cell module 2 as viewed from the direction A in FIG. 1 in the vicinity of the center thereof. 3 is a cross-sectional view of the fuel cell module 2 as viewed from the direction B in FIG. 2 in the vicinity of the center thereof. FIG. 4 is a perspective view showing a state where a part of the casing 56 covering the fuel cell assembly is removed from the fuel cell module 2 shown in FIG.

  As shown in FIGS. 2 to 4, the fuel cell assembly 12 of the fuel cell module 2 is entirely covered with a casing 56. As shown in FIG. 4, the fuel cell assembly 12 as a whole has a substantially rectangular parallelepiped shape that is longer in the A direction than in the B direction. The upper surface on the reformer 20 side and the lower surface on the fuel gas tank 68 (gas manifold) side. , A long side surface extending along the direction A in FIG. 4 and a short side surface extending along the direction B in FIG.

  In the present embodiment, an evaporating mixer (not explicitly shown) for evaporating the water supplied from the water supply pipe 62 is provided inside the reformer 20. The evaporative mixer is heated by the combustion gas to convert water into water vapor, and to mix this water vapor with fuel gas (city gas) that is a reformed gas and air.

  The reformed gas supply pipe 60 and the water supply pipe 62 are both connected to the reformer 20 after being led into the casing 56. More specifically, as shown in FIG. 3, the reformer 20 is connected to an end on the right side in the drawing, which is an upstream end of the reformer 20.

  The reformer 20 is disposed further above the combustion chamber 18 formed above the fuel cell assembly 12. Accordingly, the reformer 20 is heated by the combustion heat of the remaining fuel gas and air after the power generation reaction, and is configured to serve as an evaporative mixer and a reformer that causes a reforming reaction. Has been.

  The upper end of the fuel supply pipe 66 is connected to the downstream end of the reformer 20 (the left end in FIG. 3). The lower end side 66 a of the fuel supply pipe 66 is disposed so as to enter the fuel gas tank 68.

  As shown in FIGS. 2 to 4, the fuel gas tank 68 is provided directly below the fuel cell assembly 12. The fuel gas tank 68 is fixed to the upper surface of the casing bottom plate 56a by using four fixing members 30 (details will be described later). Note that the number of fixing members 30 need not be four. The number and location of the fixing members 30 can be arbitrarily set in consideration of the size and weight of the fuel gas tank 68.

  A plurality of small holes (not shown) are formed along the longitudinal direction (A direction) on the outer periphery of the lower end side 66 a of the fuel supply pipe 66 inserted into the fuel gas tank 68. The fuel gas reformed by the reformer 20 is uniformly supplied in the longitudinal direction into the fuel gas tank 68 through the plurality of small holes (not shown). The fuel gas supplied to the fuel gas tank 68 is supplied into a fuel gas flow path (details will be described later) inside each fuel cell unit 16 constituting the fuel cell assembly 12, and the fuel cell unit 16 It rises up to reach the combustion chamber 18.

  Next, a structure for supplying power generation air to the inside of the fuel cell module 2 will be described with reference to FIGS. 2 to 4, 5, and 6. FIG. 5 is a schematic diagram corresponding to FIG. 2 and shows the flow of power generation air and combustion gas. FIG. 6 is a schematic diagram corresponding to FIG. 3, and similarly shows the flow of power generation air and combustion gas. As shown in these drawings, a heat exchanger 22 is provided above the reformer 20. The heat exchanger 22 is provided with a plurality of combustion gas pipes 70 and a power generation air flow path 72 formed around the combustion gas pipes 70.

  A power generation air introduction pipe 74 is attached to one end side (the right end in FIG. 3) of the upper surface of the heat exchanger 22. With this power generation air introduction pipe 74, power generation air is introduced into the heat exchanger 22 from a power generation air flow rate adjustment unit (not shown).

  As shown in FIG. 2, a pair of outlet ports 76 a of the power generation air flow path 72 is formed on the other end side (the left end in FIG. 3) on the upper side of the heat exchanger 22. The outlet port 76a is connected to a pair of communication channels 76. Further, power generation air supply passages 77 are formed on the outer sides of both sides of the casing 56 of the fuel cell module 2 in the width direction (B direction: short side surface direction).

  Therefore, power generation air is supplied to the power generation air supply path 77 from the outlet port 76 a of the power generation air flow path 72 and the communication flow path 76. The power generation air supply path 77 is formed along the longitudinal direction of the fuel cell assembly 12. Furthermore, in order to blow out the air for power generation toward each fuel cell unit 16 of the fuel cell assembly 12 in the power generation chamber 10 at a position corresponding to the lower side of the fuel cell assembly 12 below the fuel cell assembly 12. A plurality of outlets 78a and 78b are formed. The power generation air blown out from these air outlets 78 a and 78 b flows from the lower side to the upper side along the outer side of each fuel cell unit 16.

  Subsequently, a structure for discharging combustion gas generated by combustion of fuel gas and power generation air will be described. The combustion gas generated above the fuel cell unit 16 rises in the combustion chamber 18 and reaches the rectifying plate 21. As shown in FIG. 6, the rectifying plate 21 is provided with an opening 21a, and the combustion gas is guided into the opening 21a. The combustion gas that has passed through the opening 21 a reaches the other end side of the heat exchanger 22. In the heat exchanger 22, a plurality of combustion gas pipes 70 are provided for discharging combustion gas generated by combustion of fuel gas and power generation air in the combustion chamber 18. A combustion gas discharge pipe 82 is connected to the downstream end side of these combustion gas pipes 70 so that the combustion gas is discharged to the outside.

  Next, the fuel cell unit 16 will be described with reference to FIG. FIG. 7 is a partial cross-sectional view showing the fuel cell unit 16 of the present embodiment.

  As shown in FIG. 7, the fuel cell unit 16 includes a fuel cell 84 and inner electrode terminals 86 respectively connected to the vertical ends of the fuel cell 84.

  The fuel cell 84 is a tubular structure extending in the vertical direction, and includes a cylindrical inner electrode layer 90 that forms a fuel gas flow path 88 therein, a cylindrical outer electrode layer 92, an inner electrode layer 90, and an outer side. An electrolyte layer 94 is provided between the electrode layer 92 and the electrode layer 92. The inner electrode layer 90 is a fuel electrode through which fuel gas passes and becomes a (−) electrode, while the outer electrode layer 92 is an air electrode in contact with air and becomes a (+) electrode.

  Since the inner electrode terminals 86 attached to the upper end side and the lower end side of the fuel cell unit 16 have the same structure, the inner electrode terminal 86 attached to the upper end side will be specifically described here. The upper portion 90 a of the inner electrode layer 90 includes an outer peripheral surface 90 b and an upper end surface 90 c exposed to the electrolyte layer 94 and the outer electrode layer 92. The inner electrode terminal 86 is connected to the outer peripheral surface 90b of the inner electrode layer 90 through a conductive sealing material 96, and is further in direct contact with the upper end surface 90c of the inner electrode layer 90, thereby Electrically connected. A fuel gas passage 98 communicating with the fuel gas passage 88 of the inner electrode layer 90 is formed at the center of the inner electrode terminal 86.

  The inner electrode layer 90 includes, for example, a mixture of Ni and zirconia doped with at least one selected from rare earth elements such as Ca, Y, and Sc, and Ni and ceria doped with at least one selected from rare earth elements. The mixture is formed of at least one of Ni and a mixture of lanthanum garade doped with at least one selected from Sr, Mg, Co, Fe, and Cu.

  The electrolyte layer 94 is, for example, zirconia doped with at least one selected from rare earth elements such as Y and Sc, ceria doped with at least one selected from rare earth elements, lanthanum gallate doped with at least one selected from Sr and Mg, Formed from at least one of the following.

  The outer electrode layer 92 includes, for example, lanthanum manganite doped with at least one selected from Sr and Ca, lanthanum ferrite doped with at least one selected from Sr, Co, Ni and Cu, Sr, Fe, Ni and Cu. It is formed from at least one of lanthanum cobaltite doped with at least one selected from the group consisting of silver and silver.

  Next, the fuel cell stack 14 will be described with reference to FIG. FIG. 8 is a perspective view showing the fuel cell stack 14 of the present embodiment.

  As shown in FIG. 8, the fuel cell stack 14 includes 16 fuel cell units 16, and a lower end side and an upper end side of these fuel cell units 16 are respectively made of ceramic fuel gas tank upper plate 68 a and It is supported by the upper support plate 100. The fuel gas tank upper plate 68a and the upper support plate 100 are formed with through holes through which the inner electrode terminal 86 can pass.

  Furthermore, a current collector 102 and an external terminal 104 are attached to the fuel cell unit 16. The current collector 102 electrically connects the inner electrode terminal 86 attached to the inner electrode layer 90 that is a fuel electrode and the outer peripheral surface of the outer electrode layer 92 that is the air electrode of the adjacent fuel cell unit 16. To do.

  Further, the external terminals 104 are connected to the inner electrode terminals 86 at the upper and lower ends of the two fuel cell units 16 located at the ends of the fuel cell stack 14. These external terminals 104 are connected to the external terminals 104 of the fuel cell unit 16 at the end of the adjacent fuel cell stack 14, and all 160 fuel cell units 16 are connected in series. Yes.

  Next, the fixing member 30 will be described with reference to FIGS. FIG. 9 is a partial cross-sectional view of the fuel cell module 2 in the vicinity of the fixing member 30 as viewed from the direction A in FIG. FIG. 10 is a partial perspective view when a part of the fixing member 30 shown in FIG. 9 is viewed from the upper side opposite to the fuel gas tank 68. FIG. 11 is a partial perspective view when a part of the fixing member 30 shown in FIG. 9 is viewed from above the fuel gas tank 68 side.

  As described above, the fixing member 30 is a member that fixes the fuel gas tank 68 to the upper surface of the casing bottom plate 56a. By using the fixing member 30 in the present embodiment, the fuel gas tank 68 can be fixed to the casing bottom plate 56a without providing holes for fixing bolts to the casing bottom plate 56a and the fuel gas tank 68. Below, the structure of such a fixing member 30 is demonstrated in detail.

  The fixing member 30 includes a welding portion 31 that is welded and fixed to the casing bottom plate 56 a, a bolt fixing portion 33 that is welded and fixed to the fuel gas tank 68, and a connecting portion 32 that connects the welding portion 31 and the bolt fixing portion 33. The connecting portion 32 includes a strain allowing portion 32a, an L-shaped portion 32b, and a stopper portion 32c.

  The welding part 31 becomes a part which welds and fixes the fixing member 30 to the casing bottom plate 56a. The welded portion 31 is integrally formed with the strain allowing portion 32 a of the connecting portion 32.

  Here, the casing bottom plate 56a tends to be formed of a thin plate in order to reduce the weight of the fuel cell device. Therefore, it is preferable to employ spot welding as welding when fixing the welded portion 31 to the casing bottom plate 56a. This is because if the entire welded portion 31 is welded to the thin casing bottom plate 56a by, for example, fillet welding or bead welding, the thin casing bottom plate is deformed and the fuel gas tank 68 may not be horizontally fixed. On the other hand, by welding by spot welding, the area to be welded at a high temperature can be suppressed small, and the deformation of the casing bottom plate 56a can be suppressed as much as possible.

  The thickness of the welded portion 31 is a thickness that enables welding by spot welding, and is preferably as thin as possible. At least when the upper surface of the casing bottom plate 56a is used as a reference, the height of the welded portion 31 is preferably lower than the height of the strain allowing portion 32a of the connecting portion.

  The bolt fixing portion 33 is a portion for fixing the fixing member 30 to the fuel gas tank side plate 68b by welding. The bolt fixing portion 33 is fixed by the L-shaped portion 32 b of the connecting portion and the bolt 34.

  The connection part 32 is comprised including the substantially reverse concave distortion allowable part 32a, the substantially L-shaped L-shaped part 32b, and the stopper part 32c which restrict | limits the distortion | strain of the distortion allowable part 32a. The strain allowing portion 32 a and the L-shaped portion 32 b are fixed using a bolt 35.

  By forming the strain allowable portion 32a with a substantially reverse concave plate member, the strain allowable portion 32a is easily distorted in the z-axis direction of FIG. The strain allowable portion 32a sets the z-axis direction in FIG. 9 as the strain allowable direction. Here, since the operating temperature of the fuel cell rises from 600 degrees to around 1000 degrees, the temperature difference between the stopped state and the operating state becomes large, and the fuel gas tank 68 is deformed due to the influence of thermal expansion. . When the fuel gas tank 68 is deformed, the strain force acts on the fixing member 30 fixed to the fuel gas tank 68 by welding. If this strain force is transmitted to the welded portion 31 that is welded and fixed to the casing bottom plate 56a, the welded portion 31 may be damaged.

  Like the strain allowable portion 32a of the present embodiment, the strain allowable portion 32a absorbs the strain force from the fuel gas tank 68 by allowing deformation in the z-axis direction of FIG. 9 in accordance with the deformation of the fuel gas tank 68. Can do. Thereby, it is possible to suppress the strain force due to the deformation of the fuel gas tank 68 in the z-axis direction from being transmitted to the welded portion 31. That is, the welding fixation by the welding part 31 can be protected from a distortion force.

  With reference to FIG. 12, how the strain allowing portion 32 a is deformed in accordance with the deformation of the fuel gas tank 68 will be described. FIG. 12A is a diagram schematically showing the vicinity of the fixing member 30 when the fuel cell module 2 is stopped, and FIG. 12B is the fixing when the fuel cell module 2 is operating. It is a figure which shows the member 30 vicinity typically.

  When the fuel cell module 2 is operated from the stop state shown in FIG. 12A, the vicinity of the fixing member 30 located at the right end portion of the fuel gas tank 68 is heated by the heat of the fuel cell module 2 as shown in FIG. , It expands and deforms in the positive direction (right direction) of the z axis. Along with the deformation of the fuel gas tank 68, a strain force is generated in the bolt fixing portion 33 fixed to the fuel gas tank 68 by welding and the L-shaped portion 32 b fixed to the bolt fixing portion 33 with the bolt 34. Due to this strain force, the strain allowable portion 32a fixed to the L-shaped portion 32b with the bolt 35 is distorted and deformed in the positive direction of the z-axis. Thereby, since the distortion force by the deformation | transformation to the z-axis direction of the fuel gas tank 68 is absorbed by the distortion | strain tolerance part 32a, it can suppress that a distortion force is transmitted to the welding part 31. FIG.

  As shown in FIG. 11, the stopper portion 32c is connected and fixed with the upper end portion of the stopper portion 32c to the top plate portion end portion of the strain allowing portion 32a, and the both end portions of the stopper portion 32c are not connected to the strain allowing portion 32a. In addition, as shown in FIG. 9, a gap D1 is provided between the lower end portion of the stopper portion 32c and the casing bottom plate 56a. By comprising in this way, the deformation | transformation by the distortion of the distortion | strain tolerance part 32a can be restrict | limited by the lower end part of the stopper part 32c contacting the casing bottom plate 56a. Further, the supporting force in the vertical direction (y-axis direction in FIG. 9), which is reduced when the strain allowing portion 32a is deformed by strain, can be reinforced by the stopper portion 32c in contact with the casing bottom plate 56a.

  With reference to FIG. 13, the mechanism in which the stopper portion 32c limits the deformation of the strain allowing portion 32a will be described. FIG. 13A is a view schematically showing the fixing member 30 when the fuel cell module 2 is stopped, and FIG. 13B is a fixing member when the fuel cell module 2 is operating. FIG.

  When the fuel cell module 2 is operated from the stopped state shown in FIG. 13 (A), as shown in FIG. 13 (B), along with the deformation of the thermally expanded fuel gas tank 68, the strain allowing portion 32a is moved in the positive direction of the z axis. It is distorted and deformed. The deformation of the strain allowing portion 32a stops when the lower end portion of the stopper portion 32c contacts the casing bottom plate 56a. As a result, the deformation can be restricted within a range in which the strain allowable portion 32a is not damaged, and the support force in the vertical direction (y-axis direction) reduced by the deformation can be reinforced.

  As shown in FIG. 9, the L-shaped portion 32b has a strain allowable portion 32a that forms a strain allowable direction in a direction (x-axis direction) substantially orthogonal to the strain allowable direction (z-axis direction) of the strain allowable portion 32a. It is arranged on the upper surface. The bottom plate portion on the strain allowable portion 32 a side of the L-shaped portion 32 b is fixed with the strain allowable portion 32 a and the bolt 35. Accordingly, the side plate portion on the bolt fixing portion 33 side of the L-shaped portion 32b is easily distorted and deformed in the x-axis direction of FIG.

  A gap D2 is provided between the stopper portion 32c and the fuel gas tank side plate 68b. The gap D2 is set in consideration of the fact that the fuel gas tank 68 thermally expands in the negative direction of the x axis due to the heat of the fuel cell module 2. By providing such a gap D2, even when the fuel gas tank 68 is thermally expanded in the x-axis direction, the stopper portion 32c can be prevented from receiving pressure directly from the fuel gas tank side plate 68b. That is, it is possible to reduce the pressure received by the thermal expansion of the fuel gas tank 68 in the x-axis direction. Hereinafter, a mechanism for allowing the thermal expansion of the fuel gas tank 68 in the x-axis direction will be specifically described.

  When the fuel gas tank side plate 68b expands and deforms in the negative direction of the x axis in FIG. 9 due to the heat of the fuel cell module 2, the bolt fixing portion 33 that is welded and fixed to the fuel gas tank side plate 68b along with this deformation. Strain force occurs. By this strain force, the side plate portion of the L-shaped portion 32b fixed to the bolt fixing portion 33 by the bolt 34 is bent and deformed in a direction approaching the bottom plate portion of the L-shaped portion 32b. Thereby, since the distortion force by the deformation | transformation of the x-axis direction of the fuel gas tank 68 can be absorbed by the L-shaped part 32b, it can suppress that a distortion force is transmitted to the welding part 31. FIG.

  As described above, according to the fuel module 2 in the embodiment, the L-shape of the connecting portion connected to the welded portion 31 welded and fixed to the casing bottom plate 56a with respect to the bolt fixing portion 33 welded and fixed to the fuel gas tank side plate 68b. The part 32b can be fixed by a bolt 34. Thereby, the fuel gas tank 68 can be fixed to the casing 56 without making a hole in the casing 56a. That is, by using the configuration of the fuel cell module in the embodiment, it is possible to firmly fix the fuel gas tank 68 to the casing 56 while ensuring airtightness in the casing 56.

  In addition, although the fixing member 30 in embodiment mentioned above contains the L-shaped part 32b, the structure which does not include the L-shaped part 32b is also possible. FIG. 14 shows a modification of the fixing member. FIG. 14 is a view corresponding to FIG. 9 and a partial cross-sectional view in the vicinity of the fixing member in the present modification. 14 is different from the fixing member 30 in the embodiment shown in FIG. 9 in that the fixing member 30A in the modification includes the L-shaped portion 32b and the bolts 34 and 35 in the embodiment. There is no point, and the bolt fixing portion 33 of the modified example is fixed by the stopper portion 32c of the connecting portion and the bolt 36. Since other configurations are the same as the respective configurations of the fixing member 30 of the embodiment, the same reference numerals are given to the respective components, the description thereof will be omitted, and in the following, mainly the embodiments. The differences will be described.

  In the present modification, thermal expansion in the x-axis direction of the fuel gas tank 68 is allowed by the top plate portion of the strain allowing portion 32a and the stopper portion 32c. That is, the top plate portion of the strain allowable portion 32a and the stopper portion 32c have the same function as the strain allowable function of the L-shaped portion 32b of the embodiment.

  Hereinafter, a mechanism in which the fixing member 30A according to the modification allows thermal expansion of the fuel gas tank 68 in the x-axis direction will be specifically described.

  When the fuel gas tank side plate 68b expands and deforms in the negative direction of the x axis in FIG. 14 due to the heat of the fuel cell module 2, the bolt fixing portion 33 that is welded and fixed to the fuel gas tank side plate 68b along with this deformation. A strain force is generated, and the stopper portion 32c fixed to the bolt fixing portion 33 with the bolt 36 is bent and deformed in a direction approaching the top plate portion of the strain allowing portion 32a. Thereby, since the distortion force by the deformation | transformation of the x-axis direction of the fuel gas tank 68 can be absorbed by the stopper part 32c, it can suppress that the distortion force is transmitted to the welding part 31. FIG.

  Moreover, although the connection part in embodiment mentioned above is provided with the substantially reverse concave distortion allowable part 32a, it does not necessarily need to be provided with the substantially reverse concave distortion allowable part 32a. It is good also as providing a block-shaped member instead of the substantially reverse concave distortion allowable part. In this case, since the block-shaped member is not easily affected by the strain force, the stopper portion 32c for limiting the strain can be omitted, and the connecting portion can be configured only by the block-shaped member.

  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. For example, the elements included in each of the specific examples described above and their arrangement, materials, conditions, shapes, sizes, and the like are not limited to those illustrated, but can be changed as appropriate. Moreover, each element with which each embodiment mentioned above is provided can be combined as long as technically possible, and the combination of these is also included in the scope of the present invention as long as it includes the features of the present invention.

2: Fuel cell module (fuel cell device)
10: Power generation chamber 12: Fuel cell assembly 14: Fuel cell stack 16: Fuel cell unit 18: Combustion chamber 20: Reformer 21: Rectifying plate 21a: Opening 22: Heat exchanger 30: Fixing member 31: Welded portion 32a: strain allowable portion (connecting portion)
32b: L-shaped part (connecting part)
32c: Stopper part (connection part)
33: Bolt fixing portion 34, 35, 36: Bolt 56: Casing 56a: Casing bottom plate 60: Reformed gas supply pipe 62: Water supply pipe 66: Fuel supply pipe 66a: Lower end side 68: Fuel gas tank (gas manifold)
68a: Fuel gas tank upper plate 68b: Fuel gas tank side plate 70: Combustion gas pipe 72: Power generation air flow path 74: Power generation air introduction pipe 76: Communication flow path 76a: Outlet port 77: Power generation air supply paths 78a, 78b: Outlet 82: Combustion gas discharge pipe 84: Fuel cell 86: Inner electrode terminal 88: Fuel gas flow path 90: Inner electrode layer 90a: Upper part 90b: Outer peripheral surface 90c: Upper end surface 92: Outer electrode layer 94: Electrolyte layer 96 : Sealing material 98: Fuel gas flow path 100: Upper support plate 102: Current collector 104: External terminal

Claims (5)

A fuel cell device that generates power using fuel gas and oxidant gas,
A plurality of electrically connected fuel cells, and a fuel cell assembly that generates power by reacting a fuel gas and an oxidant gas in the fuel cells;
A gas manifold disposed below the fuel cell assembly and distributing and supplying fuel gas to the fuel cells;
A casing configured to store the fuel cell assembly and the gas manifold, and configured to be a sealed space inside;
A fixing member for fixing the gas manifold to the casing,
The fixing member is
A welded portion fixed by welding to the casing;
A connecting portion connected to the welded portion;
A bolt fixing portion fixed to the gas manifold by welding and fixing the connecting portion with a bolt;
A fuel cell device comprising:   The height of the welded portion is lower than the height of the connecting portion when the mounting surface of the casing on which the fixing member is mounted is used as a reference. Fuel cell device.   3. The fuel cell device according to claim 2, wherein the connecting portion includes a substantially reverse concave strain allowing portion that suppresses transmission of strain force generated in the bolt fixing portion to the welded portion.   The fuel cell device according to claim 3, wherein the connecting portion includes a stopper portion that restricts deformation due to strain of the strain allowing portion by contacting the placement surface. The connecting portion further includes a substantially L-shaped L-shaped portion,
The L-shaped portion allows strain in a direction substantially orthogonal to the strain allowable direction of the strain allowable portion,
The bolt fixing portion is fixed with the L-shaped portion and a bolt,
A gap is provided between the fixing member excluding the bolt fixing portion and the gas manifold,
The fuel cell device according to claim 3 or 4, wherein

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