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 comprises: a fuel battery lamination body; a housing that houses the fuel battery lamination body; and a regulation mechanism that is provided to an upper part of the housing, and regulates a motion of the fuel battery lamination body in the housing. The regulation mechanism comprises: a pushrod that is pressed to the upper part of the fuel battery lamination body; and an eccentric bearing that holds the pushrod and adjusts the position of the pushrod. The eccentric bearing comprises: a first member that includes a first penetration hole of a positive circle which is an outer periphery, and in which a center is separated from a center of the outer peripheral; and a second member that includes a second penetration hole of a positive circle which the outer periphery is the positive circle, and in which the center is separated from the center of the positive circle. The first member is fitted rotatably to a third penetration hole to be provided to the upper part of the housing, and the second member is fitted rotatably to the first penetration hole to be provided to the upper part of the first member. The pushrod is slidably supported to the second penetration hole.SELECTED DRAWING: Figure 3

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 withstand inputs in the roll, pitch, and yaw directions, and furthermore, it is necessary to withstand 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 unit. In this fuel cell system, a cylindrical portion provided in an upper closing portion of the first case member is inserted into a hole portion provided in an upper portion of the second case member, and a pole member having a lower end fixed to the fuel cell module is slidably inserted through the cylindrical portion. By providing the above-described cylindrical portion, 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 for each component, assembly tolerances, etc., 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, and the intended performance may not be achieved.

[0006] Therefore, an object of the present invention is to provide a fuel cell system that can exhibit 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 its 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 part of the fuel cell stack, and an eccentric bearing that holds and adjusts the position of the push rod. The eccentric bearing includes a first member having a first through hole that is a perfect circle with an outer circumference that is a perfect circle and a center that is separated from the center of the outer circumference, and a second member having a second through hole that is a perfect circle with an outer circumference that is a perfect circle and a center that is separated from the center of the outer circumference. The first member is rotatably fitted into a third through hole provided in the upper part of the housing, the second member is rotatably fitted into the first through hole provided in the upper part of the first member, and the push rod is slidably supported in the second through hole.

Effects of the Invention

[0008] According to the above aspect, it is possible to provide a fuel cell system that can exhibit 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

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Mode for Carrying Out the Invention

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

[0011] [Overall Configuration] Figure 1 is a perspective view of the fuel cell system 1 according to the present embodiment. In the following description, the x-axis direction in the figure 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 for stationary purposes 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 provided above the housing 3 that regulates the movement of the fuel cell stack 2 within the housing 3. In this embodiment, the fuel cell is described as being of the solid oxide type, but it is not limited to this.

[0014] The bottom of the fuel cell stack 2 is fixed to a fixing member 4. The fixing member 4 is a part of an auxiliary structure body that includes auxiliary equipment (such as a heat exchanger, a combustor, etc.) that exchanges 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 a support portion 5 provided on the vehicle body.

[0016] [Regulating mechanism] The regulating mechanism 6 will be described with reference to FIGS. 2 to 10.

[0017] FIG. 2 is a side view of the periphery of the regulating mechanism 6 viewed from the y-axis direction. FIG. 3 is an exploded view of the regulating mechanism 6. FIG. 4 is a cross-sectional view along a plane including the z-axis of the regulating mechanism 6. FIG. 5 is an enlarged view of the vicinity of the eccentric bearing 10 attachment portion of the first member 7, the second member 9, and the housing 3 of the eccentric bearing 10. FIG. 6 is an enlarged view of the vicinity of a receiving portion 20 (to be described later) of the fuel cell stack 2. FIG. 7 is a diagram showing the thicknesses of the first member 7 and the second member 9, the depth of the first through-hole 7A, and the depth of the third through-hole 8. FIG. 8 is a diagram explaining the relationship between the diameter of the first member 7 and the diameter of the third through-hole 8, and the relationship between the diameter of the second member 9 and the diameter of the first through-hole 7A. FIG. 9 is an enlarged view of the vicinity of the third through-hole 8 in FIG. 4. FIG. 10 is a view of the first member 7 and the second member 9 viewed from the z-axis direction.

[0018] The regulating mechanism 6 includes a push rod 11 that is pressed against the upper part of the fuel cell stack 2, and an eccentric bearing 10 that holds and adjusts the position of the push rod 11. The eccentric bearing 10 includes a first member 7 having a first through hole 7A that is a perfect circle with an outer circumference that is a perfect circle and a center that is spaced apart from the center of the outer circumference, and a second member 9 having a second through hole 9A that is a perfect circle with an outer circumference that is a perfect circle and a center that is spaced apart from the center of the outer circumference. Note that the second member 9 of the present embodiment includes a cylindrical portion 9B that protrudes from the outer edge on the lower surface side of the second through hole 9A. This is to make the sliding range with the push rod 11 longer in the longitudinal direction.

[0019] The first member 7 is rotatably fitted into a third through hole 8 provided in the upper part of the housing 3. The second member 9 is rotatably fitted into the first through hole 7A provided in the upper part of the first member 7. The push rod 11 is slidably supported in the second through hole 9A.

[0020] According to the above configuration, even if the position of the receiving portion 20 described later is displaced due to dimensional tolerances, assembly tolerances, etc., the position of the second through hole 9A can be adjusted by rotating the first member 7 and the second member 9, so that poor sliding and galling of the push rod 11 can be suppressed.

[0021] 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 stack 2, and a spring guide 16 that positions the coil spring 14. 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. 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 part. Thereby, the number of parts can be reduced compared to using separate parts for each function.

[0022] The set length adjustment mechanism includes a shaft portion 16A that is a part of the spring guide 16 and has a thread, positioning nuts 17, 18 that are screwed onto the thread of the shaft portion 16A, and a spring retainer 19 that holds the positioning nut 17.

[0023] The auxiliary guide mechanism is a part of the spring guide 16 and consists of a cylindrical portion 16C that is inserted into the coil spring 14.

[0024] The coil spring 14 is sandwiched 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.

[0025] The spring retainer 19 is a U-shaped member including a nut receiving portion 19A that abuts against the positioning nut 17 and a pair of leg portions 19B that extend downward from both ends of the nut receiving portion 19A.

[0026] 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 shaft portion 16A to move within a range corresponding to the allowable movement range of the push rod 11. This can suppress the occurrence of a setting defect in which the positioning nut 17 is set at an inappropriate position.

[0027] Further, the spring retainer 19 is configured such that the nut receiving portion 19A can rotate 360 degrees around the z-axis centered on the center of the nut receiving portion 19A and can be fixed at an arbitrary rotation angle. By configuring the spring retainer 19 having the elongated through hole 19C to be rotatable 360 degrees, it is possible to cope with any deviation in the position of the push rod 11 in any direction.

[0028] 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. The retainer holder 21 is fixed to the upper part of the housing 3 by bolts 22.

[0029] The receiving portion 20 that receives the lower end (hereinafter also referred to as the tip) of the push rod 11 is provided at the upper part of the fuel cell stack 2. Note that a configuration may be adopted in which a base plate 32 having the receiving portion 20 is fixed to the upper part of the fuel cell stack 2 with bolts 33. The tip of the push rod of the present embodiment is spherical, and the portion of the receiving portion 20 that contacts the tip of the push rod 11 is a conical recess 20A, but the present invention is not limited to this. For example, the tip of the push rod 11 may be flat, and the portion of the receiving portion 20 that contacts the tip of the push rod 11 may be cylindrical. By forming the tip of the push rod 11 into a spherical shape and the receiving portion 20 into a conical shape, even if a slight inclination of the push rod 11 occurs due to thermal expansion and contraction generated during operation / stop or minute displacement in the X-Y axis directions due to an input from the vehicle, the pressing pressure by the coil spring 14 can be kept constant.

[0030] The first through hole 7A of the first member 7 is a countersunk hole having a first countersunk portion 7B, and the second member 9 fits into the first countersunk portion 7B. The depth C of the first countersunk portion 7B is smaller than the thickness D of the second member 9. The third through hole 8 of the housing 3 is a countersunk hole having a second countersunk portion 8A, and the first member 7 fits into the second countersunk portion 8A. The depth A of the second countersunk portion 8A is smaller than the thickness B of the first member 7 (see FIG. 7). Note that the first through hole 7A is provided on the bottom surface of a recess 8B provided at the upper part of the housing 3 (see FIG. 5). This recess 8B is a portion where a pressing member 12 described later fits.

[0031] Further, the restricting mechanism 6 includes a pressing member 12 having a first pressing surface 12A that presses the upper part of the first member 7 rotatably fitted into the second countersunk portion 8A and a second pressing surface 12B that presses the upper part of the second member 9 rotatably fitted into the first countersunk portion 7B. By being pressed by this pressing member 12, relative rotation between the first member 7 and the second member 9 and between the first member 7 and the housing 3 is restricted. That is, when the position of the push rod 11 is adjusted to the position of the receiving portion 20 by rotating the first member 7 and the second member 9 and the retainer holder 21 is fixed in that state, relative rotation of the first member 7 and the second member 9 is restricted by the pressing member 12 being pressed.

[0032] The first countersunk portion 7B and the second member 9, and the second countersunk portion 8A and the first member 7 each have a tapered shape with the same taper ratio and a large diameter on the upper side and a small diameter on the lower side. And, in a state of being pressed by the pressing member 12, there is a tightening allowance between the first countersunk portion 7B and the second member 9, and between the second countersunk portion 8A and the first member 7 (see FIG. 8). As a result, when the pressing member 12 is pressed, it becomes more difficult for the first member 7 and the second member 9 to rotate, and the housing 3 and the first member 7, and the first member 7 and the second member 9 come into close contact with each other, ensuring sealing performance. Note that it is not essential to form the first countersunk portion 7B and the second member 9, and the second countersunk portion 8A and the first member 7 into a tapered shape. When not formed into a tapered shape, gaskets 40 and 41 are disposed between the bottom of the first countersunk portion 7B and the second member 9, and between the second countersunk portion 8A and the first member 7 to ensure sealing performance (see FIG. 9).

[0033] Incidentally, the eccentric bearing 10 includes a first member 7 having a first through hole 7A that is a perfect circle with an outer circumference that is a perfect circle and a center that is separated from the center of the outer circumference as described above, and a second member 9 having a second through hole 9A that is a perfect circle with an outer circumference that is a perfect circle and a center that is separated from the center of the outer circumference. And, by changing the respective rotation angles of the first member 7 and the second member 9, the position of the push rod 11 is determined. That is, the adjustable range of the position of the push rod 11 is determined by the position of the first through hole 7A in the first member 7 and the position of the second through hole 9A in the second member 9. Therefore, in the present embodiment, when the angle formed by the first direction D1 in which the center C2 of the first through hole 7A is separated from the center C1 of the first member 7 and the second direction D2 in which the center C3 of the second through hole 9A is separated from the center (that is, the center C2 of the first through hole 7A) of the second member 9 is 180 degrees, the center C3 of the second through hole 9A is configured to be displaced from the center C1 of the first member 7 in the second direction D2 (see FIG. 10). Note that the diameters of the first member 7 and the second member 9, the diameters of the first through hole 7A and the second through hole 9A, the distance between the center C1 of the first member 7 and the center C2 of the first through hole 7A, and the distance between the center C2 of the second member 9 and the center C3 of the second through hole 9A are appropriately set according to the dimensional tolerances, assembly tolerances, etc. of the fuel cell system 1 to be applied.

[0034] In FIG. 10, the dashed line P1 is the locus of the center C3 of the second through hole 9A (hereinafter also referred to as locus P1) when the second member 9 is rotated once with the first member 7 fixed. Similarly, the dashed line P2 is the locus of the center C3 of the second through hole 9A (hereinafter also referred to as locus P2) when the first member 7 is rotated once with the first direction and the second direction being the same and the second member 9 fixed to the first member 7.

[0035] According to the above configuration, by changing the rotation angles of the first member 7 and the second member 9, the center C3 of the second through hole 9A can be freely set within the region (the hatched region in FIG. 10) sandwiched between the locus P1 and the locus P2. Thereby, even if there is a deviation in the position of the center of the third through hole 8 (that is, the center C1 of the first member 7) and the receiving portion 20 due to dimensional tolerances, assembly tolerances, etc., the push rod 11 can be pressed against the receiving portion 20 without tilting.

[0036] [Modification Example] Next, a modification example of the above embodiment will be described with reference to FIG. 11. This modification example also belongs to the scope of the present invention as in the above embodiment. FIG. 11 is a view of the first member 7 and the second member 9 as viewed from the z-axis direction.

[0037] The difference between this modification example and the above embodiment lies in the relationship between the position of the second through hole 9A and the center C1 of the first member 7. Specifically, in this modification example, when the angle formed by the first direction D1 and the second direction D2 is 180 degrees, the center C3 of the second through hole 9A is located at a position overlapping the center C1 of the first member 7. Although the region (the hatched region in FIG. 11) where the second through hole 9A can be set is smaller than that of the above embodiment, according to this modification example, when the position of the center of the third through hole 8 (that is, the center C1 of the first member 7) coincides with the position of the receiving portion 20, the alignment of the second through hole 9A becomes easy.

[0038] As described above, in the present embodiment, a fuel cell system 1 is provided, which includes a fuel cell stack 2 in which fuel cells are stacked, a housing 3 that houses the fuel cell stack 2, and a restricting mechanism 6 provided above the housing 3 and configured to restrict the movement of the fuel cell stack 2 within the housing 3. In this system, the bottom of the fuel cell stack 2 is fixed to a fixing member 4, the housing 3 has a box shape with an opening at the bottom, and the bottom is fixed to a supporting member 5. The restricting mechanism 6 includes a push rod 11 that is pressed against the upper part of the fuel cell stack 2, and an eccentric bearing 10 that holds and adjusts the position of the push rod 11. The eccentric bearing 10 includes a first member 7 having a first through-hole 7A that is a perfect circle with an outer circumference being a perfect circle and a center being separated from the center of the outer circumference, and a second member 9 having a second through-hole 9A that is a perfect circle with an outer circumference being a perfect circle and a center being separated from the center of the outer circumference. The first member 7 is rotatably fitted into a third through-hole 8 provided in the upper part of the housing 3, the second member 9 is rotatably fitted into the first through-hole 7A provided in the upper part of the first member 7, and the push rod 11 is slidably supported in the second through-hole 9A. Thereby, by changing the rotation angles of the first member 7 and the second member 9, the positions of the push rod 11 in the x-direction and the y-direction can be adjusted. That is, even if the position of the fuel cell stack 2 with respect to the housing 3 is displaced due to dimensional tolerances, assembly tolerances, etc., it is possible to press the push rod 11 against the fuel cell stack 2 at an appropriate angle, and the durability and reliability of the fuel cell system 1 are improved by reducing the sliding resistance.

[0039] In the present embodiment, the second member 9 is rotatably fitted into the first through-hole 7A, and in a state where the angle formed by a first direction D1 in which the center C2 of the first through-hole 7A is separated from the center C1 of the first member 7 and a second direction D2 in which the center C3 of the second through-hole 9A is separated from the center C2 of the second member 9 is 180 degrees, the center C3 of the second through-hole 9A is located at a position displaced in the second direction D2 from the center C1 of the first member 7. Thereby, the adjustable regions of the push rod 11 in the x-direction and the y-direction can be made larger.

[0040] In this embodiment, the first through-hole 7A is a countersunk hole having a first countersunk portion 7B, and the depth C of the first countersunk portion 7B is smaller than the thickness D of the second member 9. The third through-hole 8 is a countersunk hole having a second countersunk portion 8A, and the depth A of the second countersunk portion 8A is smaller than the thickness B of the first member 7. And, a pressing member 12 is provided which has a first pressing surface 12B that presses the upper portion of the first member 7 rotatably fitted to the second countersunk portion 8A, and a second pressing surface 12A that presses the upper portion of the second member 9 rotatably fitted to the first countersunk portion 7B. By being pressed by the pressing member 12, relative rotation between the first member 7 and the second member 9, and between the first member 7 and the housing 3 is restricted. Since the first member 7 and the second member 9 are respectively housed in the countersunk portions 8A and 7B as described above, positioning of the first member 7 and the second member 9 is easy. Further, since the upper surfaces of the first member 7 and the second member 9 respectively protrude from the countersunk portions 8A and 7B, the pressing member 12 comes into reliable contact with the respective upper surfaces described above, and the first member 7 and the second member 9 can be fixed with a simple configuration.

[0041] In this embodiment, the first countersunk portion 7B and the second member 9, and the second countersunk portion 8A and the first member 7 each have a tapered shape with the same taper ratio and a larger diameter on the upper side and a smaller diameter on the lower side. In a state of being pressed by the pressing member 12, there is an interference fit between the first countersunk portion 7B and the second member 9, and between the second countersunk portion 8A and the first member 7. Thereby, the first member 7 and the second member 9 are press-fitted into the second countersunk portion 8A and the first countersunk portion 7B respectively by being pressed by the pressing member 12, displacement due to vibration or the like is suppressed, and sealing performance can be ensured.

[0042] In this embodiment, instead of making the first member 7 and the second member 9 have the above-described tapered shape, gaskets 40 and 41 may be disposed between the bottom of the first countersunk portion 7B and the second member 9, and between the second countersunk portion 8A and the first member 7. Even with this configuration, displacement of the first member 7 and the second member 9 is suppressed by being pressed by the pressing member 12, and sealing performance can also be ensured.

[0043] In this modification, the second member 9 is rotatably fitted into the first through hole 7A, and the first direction D1 in which the center C2 of the first through hole 7A is separated from the center C1 of the first member 7 and the center C3 of the second through hole 9A are separated from the center C2 of the second member 9. The center C3 of the second through hole 9A is located at a position overlapping the center C1 of the first member 7 in a state where the angle formed by the second direction D2 is 180 degrees. As a result, when the positions of the second through hole 9A and the receiving portion 20 are as designed, the positioning of the first member 7 and the second member 9 becomes easy.

[0044] As described above, the embodiments of the present invention have been described. 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

[0045] 1 Fuel cell system, 2 Fuel cell stack, 3 Housing, 6 Regulation mechanism, 7 First member, 8 Third through hole, 9 Second member, 10 Eccentric 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 on an upper portion of the housing and configured to regulate movement of the fuel cell stack within the housing, In a fuel cell system including: 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 an upper portion of the fuel cell stack, and an eccentric bearing that holds and adjusts the position of the push rod, the eccentric bearing includes a first member having a first through hole that is a perfect circle with an outer circumference that is a perfect circle and a center that is spaced apart from the center of the outer circumference, and a second member having a second through hole that is a perfect circle with an outer circumference that is a perfect circle and a center that is spaced apart from the center of the outer circumference, and the first member is rotatably fitted into a third through hole provided in an upper portion of the housing, the second member is rotatably fitted into the first through hole provided in an upper portion of the first member, the fuel cell system, wherein the push rod is slidably supported by the second through hole.

2. In the fuel cell system according to claim 1, the second member is rotatably fitted into the first through hole, and in a state where an angle formed by a first direction in which the center of the first through hole is spaced apart from the center of the first member and a second direction in which the center of the second through hole is spaced apart from the center of the second member is 180 degrees, the center of the second through hole is offset from the center of the first member in the second direction.

3. In the fuel cell system according to claim 1, the second member is rotatably fitted into the first through hole, and in a state where an angle formed by a first direction in which the center of the first through hole is spaced apart from the center of the first member and a second direction in which the center of the second through hole is spaced apart from the center of the second member is 180 degrees, the center of the second through hole overlaps with the center of the first member.

4. In the fuel cell system according to claim 1, the first through hole is a countersunk hole having a first countersunk portion, and a depth of the first countersunk portion is smaller than a thickness of the second member, the third through hole is a countersunk hole having a second countersunk portion, and a depth of the second countersunk portion is smaller than a thickness of the first member. A pressing member having a first pressing surface that presses an upper portion of the first member rotatably fitted to the second counterbore portion and a second pressing surface that presses an upper portion of the second member rotatably fitted to the first counterbore portion is provided. A fuel cell system in which relative rotation between the first member and the second member and between the first member and the housing is restricted by being pressed by the pressing member.

5. In the fuel cell system according to claim 4, The first counterbore portion and the second member, and the second counterbore portion and the first member each have a tapered shape with the same taper ratio and a large diameter on the upper side and a small diameter on the lower side. A fuel cell system having a tightening allowance between the first counterbore portion and the second member and between the second counterbore portion and the first member in a state of being pressed by the pressing member.

6. In the fuel cell system according to claim 1, A fuel cell system in which gaskets are disposed between the bottom of the first counterbore portion and the second member and between the second counterbore portion and the first member.

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