Fuel battery system

Abstract

To provide a fuel battery system capable of exerting a performance to be intended even in the case where there is a dimensional tolerance or the like.SOLUTION: A fuel battery system 1 comprises: a fuel battery lamination body 2 in which a fuel battery cell is laminated; a housing 3 that houses the fuel battery lamination body 2; and a regulation mechanism 6 that is provided to an upper part of the housing 3, and regulates a motion of the fuel battery lamination body 2 in the housing 3. In the fuel battery lamination body 2, a bottom part is fixed to a fixed member 4. The housing 3 has a box shape having an open part in the bottom part. The regulation mechanism 6 comprises: a pushrod 11 to be pressed to the upper part of the fuel battery lamination body 2; and a spherical surface sliding bearing 10 that holds the pushrod 11. The spherical surface sliding bearing 10 comprises: a cylinder body 7 that includes a penetration hole to which the pushrod 11 is penetrated, and includes a spherical surface part 7A to one part of an outer periphery; and holding parts 8 and 9 that hold the spherical surface part 7A. At least one part of the spherical surface part 7A is contacted to the housing 3.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a fuel cell system.

Background Art

[0002] A fuel cell system including a fuel cell stack in which a plurality of fuel cells are stacked needs to be fixed so as not to fall over or the like in response to an external input. In particular, when mounted on a vehicle, unlike for stationary use, it is necessary to counter inputs in each direction of roll, pitch, and yaw, and furthermore, it is necessary to counter large inputs during a collision or the like. Therefore, it is necessary to fix it so as not to disassemble or shift in position in response to these inputs. It is also necessary to absorb dimensional changes in the stacking direction due to the temperature difference between when the system is stopped and when it is generating power.

[0003] As a configuration that satisfies these requirements, Patent Document 1 discloses a fuel cell system including a first case member that houses a fuel cell module and a second case member that houses the first case member and a fluid section. In this fuel cell system, a cylindrical section provided in an upper closing section of the first case member is inserted into a hole section provided in the upper part of the second case member, and a pole member whose lower end is fixed to the fuel cell module is slidably inserted through the cylindrical section. By providing the above-described cylindrical section, the fuel cell module is fixed within the second case member, and by making the pole member slidable, dimensional changes in the stacking direction can be absorbed.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, due to dimensional tolerances and assembly tolerances for each component, the positions of the cylindrical portion of the first case member, the hole portion of the second case, and the pole member do not always match the design. When assembly is performed with these positions misaligned, there is a risk of poor sliding of the pole member or so-called jamming, resulting in the inability to exhibit the intended performance.

[0006] Therefore, an object of the present invention is to provide a fuel cell system that can exhibit the intended performance even in the presence of dimensional tolerances and the like.

Means for Solving the Problems

[0007] According to an aspect of the present invention, there is provided a fuel cell system including a fuel cell stack in which fuel cells are stacked, a housing that houses the fuel cell stack, and a regulating mechanism provided above the housing and configured to regulate the movement of the fuel cell stack within the housing. In this system, the fuel cell stack has a bottom fixed to a fixing member, the housing has a box shape with an opening at the bottom, and the regulating mechanism includes a push rod that is pressed against the upper portion of the fuel cell stack and a spherical plain bearing that holds the push rod. The spherical plain bearing includes a cylindrical body having a through-hole through which the push rod passes and a spherical surface portion on a part of the outer periphery, and a holding portion that holds the spherical surface portion, and at least a part of the spherical surface portion is in contact with the housing.

Effects of the Invention

[0008] According to the above aspect, it is possible to provide a fuel cell system that can exhibit the intended performance even in the presence of dimensional tolerances and the like.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

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Figure 6

Figure 7

Figure 8

Figure 9

BEST MODE FOR CARRYING OUT THE INVENTION

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0011] [Overall Configuration] FIG. 1 is a perspective view of a fuel cell system 1 according to the present embodiment. In the following description, the x-axis direction in the drawing is the horizontal direction, the y-axis direction is the vertical direction, and the z-axis direction is the vertical direction or the stacking direction.

[0012] In the present embodiment, the fuel cell system 1 will be described as being for in-vehicle use, but use as a stationary type is not excluded.

[0013] The fuel cell system 1 includes a fuel cell stack 2 in which fuel cells are stacked, a housing 3 that houses the fuel cell stack 2, and a regulating mechanism 6 that is provided above the housing 3 and regulates the movement of the fuel cell stack 2 in the housing 3. In the present embodiment, the fuel cell is described as being of a solid oxide type, but it is not limited thereto.

[0014] The bottom of the fuel cell stack 2 is fixed to the first fixing member 4. The first fixing member 4 is a part of an auxiliary structure body that includes auxiliary devices (for example, a heat exchanger, a combustor, etc.) that exchange gas with the fuel cell stack.

[0015] The housing 3 has a box shape with an opening at the bottom, and the bottom is fixed to the second fixing member 5 provided on the vehicle body.

[0016] [Regulating mechanism] The regulating mechanism 6 will be described with reference to FIGS. 2 to 8.

[0017] FIG. 2 is a side view of the periphery of the regulating mechanism 6 as viewed from the y-axis direction. FIG. 3 is an exploded view of the regulating mechanism 6. FIG. 4 is a cross-sectional view taken along a plane including the z-axis of the regulating mechanism 6. FIG. 5 is a cross-sectional view of the regulating mechanism 6 and the housing 3. FIG. 6 is an enlarged view of the periphery of the receiving portion 20 (to be described later) of the fuel cell stack 2.

[0018] The regulating mechanism 6 includes a push rod 11 that is pressed against the upper part of the fuel cell stack 2, and a spherical sliding bearing 10 that holds the push rod 11. Thereby, the push rod 11 can be directed in an arbitrary direction. That is, even if there is a deviation between the position where the regulating mechanism 6 of the housing 3 is attached and the position of the receiving portion 20 (to be described later) of the fuel cell stack 2 due to dimensional tolerances, assembly tolerances, etc., by tilting and assembling the push rod 11, it is possible to suppress poor sliding of the push rod 11 and the occurrence of so-called galling.

[0019] The spherical sliding bearing 10 includes a cylindrical body 7 that has a through hole through which the push rod 11 passes and has a spherical surface portion 7A on a part of the outer periphery, and a holding portion that holds the spherical surface portion 7A.

[0020] The holding portion includes a lower holding portion 8 that supports the spherical surface portion 7A from the side of the fuel cell stack 2 (that is, downward) in the longitudinal direction of the push rod 11, and an upper holding portion (hereinafter also referred to as a retainer) 9 that supports the spherical surface portion 7A from the side opposite to the lower holding portion 8 (that is, upward).

[0021] The lower holding portion 8 is formed at the upper part of the housing 3. As a result, at least a part of the spherical surface portion 7A comes into contact with the housing 3. The fuel cell during power generation may reach a high temperature of 500°C or higher, and the heat is transmitted to the push rod 11 through the fuel cell laminate 2 and a receiving portion 20 described later. In the present embodiment, since the spherical surface portion 7A of the spherical plain bearing 10 that holds the push rod 11 is in contact with the housing 3, the heat of the push rod 11 is easily dissipated to the housing 3 through the spherical surface portion 7A. Thereby, the temperature rise of each component of the regulating mechanism 6 is suppressed, and the reliability of the regulating mechanism 6 is improved.

[0022] The retainer 9 is a separate member from the lower holding portion 8. And when the retainer 9 is pressed against the spherical surface portion 7A, the movement of the spherical surface portion 7A is restricted. The retainer 9 is pressed by a retainer holder 21 via a shim 12, a holder 13, and a leg portion 19B of a spring retainer 19 described later. Note that at the upper part of the housing 3, a first countersink 31 for accommodating the shim 12 and a second countersink 30 for accommodating the holder 13 are provided. In this way, since a part of the regulating mechanism 6 is formed in the housing 3, the structure is simplified and the number of components is small. And since it is only necessary to fix the retainer 9 after determining the direction of the push rod 11, the adjustment is easy.

[0023] Further, the regulating mechanism 6 further includes a coil spring 14 that generates a force for pressing the push rod 11 against the fuel cell laminate 2, and a spring guide 16 that positions the coil spring 14. The spring guide 16 includes a part of a set length adjusting mechanism for adjusting the set length of the coil spring 14, and an auxiliary guide mechanism for restricting the direction when the push rod 11 moves in the longitudinal direction. That is, the spring guide 16 has three functions of positioning the coil spring 14, adjusting the set length, and auxiliary guiding with a single component. Thereby, the number of components can be reduced as compared with using separate components for each function.

[0024] The set length adjustment mechanism includes a shaft portion 16A which is part of the spring guide 16 and has a thread, a positioning nut 17 screwed onto the thread of the shaft portion 16A, and a spring retainer 19 for holding the positioning nut 17.

[0025] The auxiliary guide mechanism consists of a cylindrical portion 16C which is part of the spring guide 16 and through which the coil spring 14 is inserted.

[0026] The coil spring 14 is clamped between a flange portion 11A provided on the push rod 11 and a flange portion 16B provided on the spring guide 16. A spring seat 15 is interposed between the coil spring 14 and the flange portion 16B of the spring guide 16. This coil spring 14 not only generates a force to press the push rod 11 against the fuel cell stack 2, but also functions to absorb changes in the dimensional change in the stacking direction due to the expansion and contraction of the fuel cell stack.

[0027] The spring retainer 19 has a nut receiving portion 19A that abuts against the positioning nut 17, and the nut receiving portion 19A has an arc shape with an arbitrary radius centered on the rotation center of the spherical plain bearing 10. By adopting such an arc shape, the inclination of the push rod 11 can be changed without changing the set length of the spring guide 16.

[0028] Also, the spring retainer 19 includes a nut receiving portion 19A and a pair of leg portions 19B extending downward from both ends of the nut receiving portion 19A. Note that the positioning nut 17 may be configured to abut against the nut receiving portion 19A via the position adjusting nut 18.

[0029] The nut receiving portion 19A has a through hole 19C through which the shaft portion 16A passes. The through hole 19C is an elongated hole that allows the movement of the shaft portion 16A within a range corresponding to the allowable inclination of the push rod 11. Thereby, the occurrence of a setting defect in which the positioning nut 17 is set at an inappropriate position can be suppressed.

[0030] Note that a pair of protrusions parallel to the longitudinal direction of the through hole 19C may be provided on both sides in the short side direction of the through hole 19C of the nut receiving portion 19A. These protrusions not only function as guide rails for the positioning nut 17 or the position adjusting nut 18, but also function as reinforcing members for the nut receiving portion 19A.

[0031] Further, the spring retainer 19 is configured such that the nut receiving portion 19A can rotate 360 degrees around the z-axis with the center of the nut receiving portion 19A as the center and can be fixed at an arbitrary rotation angle. By configuring the spring retainer 19 having the long hole through hole 19C to be rotatable 360 degrees, it is possible to cope with any direction of the inclination of the push rod 11.

[0032] The rotation angle of the spring retainer 19 is fixed by sandwiching a flange provided at the lower end of the leg portion 19B of the spring retainer 19 between the retainer holder 21 and the housing 3. Note that the retainer holder 21 is fixed to the upper part of the housing 3 by bolts 22.

[0033] The receiving portion 20 that receives the lower end portion (hereinafter also referred to as the tip) of the push rod 11 is provided above the fuel cell stack 2. Note that a configuration in which a base plate 32 including the receiving portion 20 is fixed to the upper part of the fuel cell stack 2 with bolts 33 may be employed.

[0034] Here, the shapes of the tip of the push rod 11 and the receiving portion 20 will be described with reference to FIGS. 7 and 8. FIG. 7 is a cross-sectional view showing a state where the tip of the push rod 11 is pressed against the receiving portion 20. FIG. 8 is a diagram for explaining the dimensions and the like of the tip of the push rod 11 and the receiving portion 20.

[0035] The end of the push rod 11 on the fuel cell stack 2 side is a spherical surface portion 11D, and the receiving portion 20 has a conical recess 20A. As a result, the push rod 11 and the receiving portion 20 are in a contact form close to line contact, and even if the push rod 11 is inclined with respect to the z-axis direction, the contact form does not change. Further, no matter in which direction the receiving portion 20 is displaced with respect to the push rod 11 in the z-axis direction view, it can follow while maintaining the above contact form.

[0036] The cross-sectional shape of the recess 20A along the longitudinal direction of the push rod 11 is an equilateral triangle, and the depth B is the same as the diameter A of the spherical surface portion 11D of the push rod 11. Further, the outer diameter E of the push rod 11 is larger than the diameter A of the spherical surface portion 11D. And in the cross-section including the central axis of the push rod 11, the angle θc formed by the straight line L1 connecting the spherical surface portion 11D and the side surface of the push rod 11 and the central axis C is smaller than the angle θd formed by the generatrix L2 of the recess 20A and the central axis C. As a result, the spherical surface portion 11D comes into contact with a relatively shallow position of the recess 20A, that is, a position with a relatively large diameter, so that a wide contact area can be ensured. Further, since it contacts at a position lower than the upper end of the recess 20A, even when there is an impact input or the like, the spherical surface portion 11D is difficult to come off from the recess 20A.

[0037] [Modification Example] Next, a modification example of the above embodiment will be described with reference to FIG. 9. This modification example also belongs to the scope of the present invention in the same manner as the above embodiment. FIG. 9 is an enlarged view around the regulating mechanism 6 of the fuel cell system according to this modification example.

[0038] The difference between this modification example and the above embodiment is the shape of the housing 3. Specifically, the housing 3 of this modification example has a shape in which the upper part, the portion where the regulating mechanism 6 is provided, protrudes upward more than the other parts. That is, only the portion where the retainer holder 21 is fixed in the upper part of the housing 3 protrudes upward, and the other parts are the same as those in the above embodiment.

[0039] As a result, the distance from the fuel cell stack, which is the heating element, to the regulating mechanism 6 can be made longer than the configuration of the above embodiment, so that the regulating mechanism 6 is less likely to be damaged by heat.

[0040] Also, since only the attachment portion of the regulating mechanism 6 protrudes upward, the heat dissipation from the lower holding portion 8 provided on the upper portion of the housing 3 is improved compared to the configuration of the above embodiment. As a result, the durability and reliability of the regulating mechanism 6 are improved.

[0041] Furthermore, as the distance from the fuel cell stack to the regulating mechanism 6 becomes longer, the distance from the rotation center of the spherical plain bearing 10 to the receiving portion 20 also becomes longer. As a result, when there is a deviation between the rotation center of the spherical plain bearing 10 and the center of the receiving portion 20 in the view in the z-axis direction, the inclination of the push rod 11 with respect to the z-axis is smaller than that in the configuration of the above embodiment. Thereby, the deviation between the input direction of the reaction force from the fuel cell stack 2 to the push rod 11 and the sliding direction of the push rod 11 becomes smaller, so that the sliding resistance of the push rod 11 and the bending moment applied to the push rod 11 are reduced. As a result, the durability and reliability of the regulating mechanism 6 are improved.

[0042] As described above, in the present embodiment, there is provided a fuel cell system including a fuel cell stack 2 in which fuel cells are stacked, a housing 3 that houses the fuel cell stack 2, and a regulating mechanism 6 provided on the upper portion of the housing 3 to regulate the movement of the fuel cell stack 2 in the housing 3. The bottom of the fuel cell stack 2 is fixed to the fixing member 4. The housing 3 has a box shape with an opening at the bottom. The regulating mechanism 6 includes a push rod 11 that is pressed against the upper portion of the fuel cell stack 2, and a spherical plain bearing 10 that holds the push rod 11. The spherical plain bearing 10 includes a cylindrical body 7 having a through hole through which the push rod 11 passes and having a spherical surface portion 7A on a part of the outer periphery, and a holding portion (lower holding portion 8, retainer 9) that holds the spherical surface portion 7A, and at least a part of the spherical surface portion 7A is in contact with the housing 3. Thereby, even if there is a deviation between the position where the regulating mechanism 6 of the housing 3 is attached and the position of a receiving portion 20 (to be described later) of the fuel cell stack 2 due to dimensional tolerances, assembly tolerances, etc., by tilting and assembling the push rod 11, it is possible to suppress the occurrence of sliding failure of the push rod 11 and so-called jamming. Further, since at least a part of the spherical surface portion 7A is in contact with the housing 3, the heat dissipation of the regulating mechanism 6 is improved.

[0043] In this embodiment, the holding part includes a lower holding part 8 that supports the spherical surface part 7A from the side of the fuel cell stack 2 in the longitudinal direction of the push rod 11, and an upper holding part (retainer) 9 that supports the spherical surface part 7A from the side opposite to the lower holding part 8. The lower holding part 8 is formed at the upper part of the housing 3, the retainer 9 is a separate member from the lower holding part 8, and the movement of the spherical surface part 7A is restricted by pressing the retainer 9 against the spherical surface part 7A. Thereby, simplification of the structure, reduction of the number of parts, and facilitation of adjustment can be achieved.

[0044] In this embodiment, a receiving part 20 for receiving the push rod 11 is provided at the upper part of the fuel cell stack 2, the end part of the push rod 11 on the side of the fuel cell stack 2 is a spherical surface part 11D, and the receiving part 20 has a conical recess 20A. Thereby, the push rod 11 and the receiving part 20 are in a contact form close to line contact, and even if the push rod 11 is inclined with respect to the z-axis direction, it can follow while maintaining the above contact form.

[0045] In this embodiment, the cross-sectional shape of the recess 20A along the longitudinal direction of the push rod 11 is an equilateral triangle, and the depth B is the same as the diameter A of the spherical surface part 11D of the push rod 11. Thereby, the spherical surface part 11D comes into contact with a relatively shallow position of the recess 20A, that is, a position with a relatively large diameter, so that a wide contact area can be ensured.

[0046] In this embodiment, the outer diameter E of the push rod 11 is larger than the diameter A of the spherical surface part 11D of the push rod 11, and in a cross-section including the central axis C of the push rod 11, the angle θc formed by the straight line L1 connecting the spherical surface part 11D of the push rod 11 and the side surface of the push rod 11 and the central axis C is smaller than the angle θd formed by the generatrix L2 of the recess 20A and the central axis C. Thereby, since the push rod 11 and the receiving part 20 come into contact at a position lower than the upper end of the recess 20A, even when there is an impact input or the like, the spherical surface part 11D is difficult to come out of the recess 20A.

[0047] In this embodiment, a coil spring 14 that generates a force for pressing the push rod 11 against the fuel cell stack 2, and a spring guide 16 that positions the coil spring 14 are further provided. The spring guide 16 includes a part of a set length adjustment mechanism that adjusts the set length of the coil spring 14, and an auxiliary guide mechanism that restricts the direction when the push rod 11 moves in the longitudinal direction. In this way, by giving the spring guide 16 three functions: positioning of the coil spring 14, set length adjustment, and auxiliary guide, the number of parts can be reduced compared to using separate parts for each function.

[0048] In this embodiment, the set length adjustment mechanism includes a shaft portion 16A having a thread, which is a part of the spring guide 16, a positioning nut 17 that is screwed onto the thread of the shaft portion 16A, and a spring retainer 19 that holds the positioning nut 17. The spring retainer 19 has a nut receiving portion 19A that abuts against the positioning nut 17 (position adjustment nut 18 in FIG. 3). The nut receiving portion 19A has an arc shape with an arbitrary radius centered on the rotation center of the spherical sliding bearing 10, and has a through hole 19C through which the shaft portion 16A passes. The through hole 19C is a long hole that allows the movement of the shaft portion 16A within a range corresponding to the allowable inclination of the push rod 11. Thereby, the inclination of the push rod 11 can be changed without changing the set length of the spring guide 16. In addition, the occurrence of a setting defect in which the positioning nut 17 is set at an inappropriate position can be suppressed.

[0049] In this embodiment, the spring retainer 19 is configured such that the nut receiving portion 19A can rotate 360 degrees around the center of the nut receiving portion and can be fixed at an arbitrary rotation angle. Thereby, it is possible to cope with the inclination of the push rod 11 in any direction.

[0050] In this modification example, the upper part of the housing 3 has a portion where the regulating mechanism 6 is provided protruding upward more than the other parts. As a result, the regulating mechanism 6 is less likely to be affected by heat damage. Also, the heat dissipation property from the regulating mechanism 6 is improved. Furthermore, the inclination of the push rod 11 with respect to the displacement between the regulating mechanism 6 and the receiving portion 20 becomes smaller, and the durability and reliability of the regulating mechanism 6 are improved.

[0051] As described above, the embodiments of the present invention have been explained. However, the above embodiments merely show a part of the application examples of the present invention, and are not intended to limit the technical scope of the present invention to the specific configurations of the above embodiments.

Explanation of Reference Numerals

[0052] 1 Fuel cell system, 2 Fuel cell stack, 3 Housing, 6 Regulating mechanism, 7 Cylindrical body, 8 Lower holding portion, 9 Upper holding portion (retainer), 10 Spherical sliding bearing, 11 Push rod, 16 Spring guide, 19 Spring retainer, 20 Receiving portion

Claims

1. A fuel cell stack in which fuel cells are stacked, a housing that houses the fuel cell stack, a regulating mechanism provided above the housing for regulating the movement of the fuel cell stack within the housing, In a fuel cell system comprising: the bottom of the fuel cell stack is fixed to a fixing member, the housing has a box shape with an opening at the bottom, the regulating mechanism includes a push rod that is pressed against the upper part of the fuel cell stack and a spherical plain bearing that holds the push rod, the spherical plain bearing includes a cylindrical body having a through hole through which the push rod passes and a spherical surface portion on a part of the outer periphery, and a holding portion that holds the spherical surface portion, at least a part of the spherical surface portion is in contact with the housing, characterized in that it is a fuel cell system.

2. In the fuel cell system according to claim 1, the holding portion includes a lower holding portion that supports the spherical surface portion from the fuel cell stack side in the longitudinal direction of the push rod and an upper holding portion that supports the spherical surface portion from the side facing the lower holding portion, the lower holding portion is formed on the upper part of the housing, the upper holding portion is a separate member from the lower holding portion, a fuel cell system in which the movement of the spherical surface portion is restricted by the upper holding portion being pressed against the spherical surface portion.

3. In the fuel cell system according to claim 1, the fuel cell stack is provided with a receiving portion for receiving the push rod at the upper part, the end of the push rod on the fuel cell stack side is a spherical surface portion, the receiving portion has a conical recess, characterized in that it is a fuel cell system.

4. In the fuel cell system according to claim 3, the cross-sectional shape of the recess along the longitudinal direction of the push rod is an equilateral triangle, and the depth is the same as the diameter of the spherical surface portion of the push rod, characterized in that it is a fuel cell system.

5. In the fuel cell system according to claim 4, the outer diameter of the push rod is larger than the diameter of the spherical surface portion of the push rod, in a cross-section including the central axis of the push rod, the angle formed by the straight line connecting the spherical surface portion of the push rod and the side surface of the push rod and the central axis is smaller than the angle formed by the generatrix of the recess and the central axis, characterized in that it is a fuel cell system.

6. In the fuel cell system according to claim 1, A fuel cell system in which the upper part of the housing has a portion provided with the regulating mechanism protruding upward from other portions.

7. In the fuel cell system according to claim 1, a coil spring that generates a force for pressing the push rod against the fuel cell stack, and a spring guide for positioning the coil spring, further comprising: The spring guide includes a part of a set length adjusting mechanism for adjusting the set length of the coil spring, and an auxiliary guide mechanism for restricting the direction when the push rod moves in the longitudinal direction. A fuel cell system.

8. In the fuel cell system according to claim 7, The set length adjusting mechanism includes a shaft portion having a thread, which is a part of the spring guide, a positioning nut screwed onto the thread of the shaft portion, and a spring retainer for holding the positioning nut. The spring retainer has a nut receiving portion that abuts against the positioning nut. The nut receiving portion has an arc shape with an arbitrary radius centered on the rotation center of the spherical sliding bearing, and has a through hole through which the shaft portion passes. The through hole is an elongated hole that allows the movement of the shaft portion within a range corresponding to the allowable inclination of the push rod. A fuel cell system.

9. In the fuel cell system according to claim 8, The spring retainer is configured such that the nut receiving portion can rotate 360 degrees around the center of the nut receiving portion and can be fixed at an arbitrary rotation angle. A fuel cell system.

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