JP2008060011A - Cell pressing assembly for fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cell pressing assembly for a fuel cell capable of being simply assembled and suppressing the positional misalignment of an interposed elastic member. <P>SOLUTION: The cell pressing assembly 1 for the fuel cell is equipped with an end side member 2 to which a load is applied from the outside; a cell side member 4 facing the end side member 2 and adjoining a cell stack 8 more than the end side member 2; and an elastic member 3 interposed between the end side member 2 and the cell side member 4 and capable of storing elastic energy for pressing the cell stack 8. The end side member 2 and the cell side member 4 are joined so as to hold the elastic member 3, and each has facing surfaces 26, 46 facing each other, and a positioning projection part 40a for positioning the elastic member 3 is installed in at least one of a pair of facing surfaces 26, 46. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a cell pressing assembly for a fuel cell for pressing and fastening a cell stack of a fuel cell.

  The fuel cell has high power generation efficiency, clean gas discharged, and extremely little influence on the environment. In particular, the polymer electrolyte fuel cell can be operated at a low temperature of about 80 ° C. and has a large output density, and therefore is expected to be used in various applications such as power generation and automobiles. In a polymer electrolyte fuel cell, a cell in which an electrolyte membrane electrode assembly (MEA) is sandwiched between separators serves as a power generation unit. The MEA includes a polymer membrane (electrolyte membrane) serving as an electrolyte and a pair of electrodes (fuel electrode and oxygen electrode) disposed on both sides of the electrolyte membrane. The fuel electrode of the cell is supplied with a fuel gas such as hydrogen or hydrocarbon, and the oxygen electrode is supplied with an oxidant gas such as oxygen or air. The electrochemical reaction at the three-phase interface between the supplied gas, electrolyte and electrode. Power is generated by The polymer electrolyte fuel cell is configured by fastening a cell laminate in which the cells are laminated with end plates arranged at both ends in the cell lamination direction.

The cell stack is assembled to the fuel cell in a state where a predetermined fastening load is applied for the purpose of reducing electrode contact resistance and ensuring the sealing performance of the reaction gas and water. For example, Patent Document 1 discloses a cell pressing assembly for a fuel cell for pressing and fastening a cell stack. The cell pressing assembly for a fuel cell includes a first plate, a second plate, and a plurality of coil springs interposed between the two plates.
JP 2004-288618 A

  In such a cell pressing assembly for a fuel cell, the first plate is first arranged horizontally, then a plurality of coil springs are arranged as elastic members on the first plate, and finally the second plate is covered from above the coil spring. Is assembled.

  However, the upper ends of the individual coil springs are inclined in all directions due to their own weight and the like. For this reason, it is not easy to position the coil spring at a predetermined position during assembly. In addition, even after assembly, the position of the coil spring may be shifted during transportation or use.

  This invention is made | formed in view of such a situation, and makes it a subject to provide the cell press assembly for fuel cells with which the assembly was easy and the position shift of the interposed elastic member was suppressed.

  (1) The fuel cell cell pressing assembly according to the present invention is arranged to face the end side member to which a load is applied from the outside, the end side member, and closer to the cell stack than the end side member. A fuel cell comprising: a cell-side member that is formed; and an elastic member that is interposed between the end-side member and the cell-side member and is capable of storing elastic energy for pressing the cell stack. In the cell pressing assembly, the end side member and the cell side member are connected to each other so as to hold the elastic member, and each include an opposing surface, and at least one of the pair of opposing surfaces. On one side, a positioning convex portion for positioning the elastic member is arranged.

  The fuel cell cell pressing assembly of the present invention (hereinafter referred to as “the cell pressing assembly of the present invention” as appropriate) is disposed, for example, between the end plate and the cell stack, and applies a load from the end plate side. To press the cell stack. That is, when the cell pressing assembly of the present invention is assembled to the fuel cell, the end side member moves in the direction of the cell side member against the elastic force of the elastic member due to the load applied from the end plate side. Further, the cell side member is urged toward the cell laminate by the elastic member, and presses the cell laminate.

  Here, a positioning convex portion for positioning the elastic member is disposed on at least one of the opposing surfaces of the end side member and the cell side member. Therefore, at the time of assembling the cell pressing assembly of the present invention, the elastic member can be easily positioned. For example, when a spring group including a plurality of coil springs is employed as the elastic member, the end of the coil spring is positioned from at least one of the inner peripheral side and the outer peripheral side. For this reason, positioning of a coil spring can be performed easily. As described above, according to the cell pressing assembly of the present invention, the assembly of the elastic member is facilitated, and as a result, the assembly of the cell pressing assembly of the present invention is facilitated.

  In addition, after assembling the cell pressing assembly of the present invention, the elastic member is held by the positioning convex portion. For example, when a spring group composed of a plurality of coil springs is employed as the elastic member, the end of the coil spring is held from at least one of the inner peripheral side and the outer peripheral side. For this reason, the displacement of the elastic member at the time of conveyance or use is suppressed. Therefore, the cell pressing assembly of the present invention is easy to handle.

  In the cell pressing assembly of the present invention, the end side member and the cell side member are connected to each other so as to hold the elastic member. Thus, since the cell pressing assembly is modularized, it is possible to easily manufacture and replace the fuel cell.

  (2) Preferably, the elastic member may be a spring group including a plurality of coil springs. The coil spring is easy to handle and it is easy to ensure a desired stroke length according to the expansion and contraction of the cell laminate. Furthermore, the fastening load of the cell stack can be adjusted by appropriately arranging the plurality of coil springs over the entire area of the electrode surface of the cell.

  (3) Preferably, in the configuration of (2), the positioning convex portion has an inclined surface that is positioned so that the end of the coil spring is positioned from the inner peripheral side and approaches the central axis of the coil spring. It is good to set it as the structure which is an inclination convex part with. In this configuration, the inclined surface of the inclined convex portion serves to guide the inner peripheral surface of the end portion of the coil spring. That is, at the time of assembling the cell pressing assembly of the present invention, when the coil spring is displaced from the predetermined position after assembly, the coil spring can be corrected to the predetermined position by the inclined surface. Further, the inclined surface is inclined so as to approach the central axis of the coil spring. For this reason, when the coil spring expands and contracts, the inclined convex portion and the coil spring hardly interfere with each other. Further, even when the coil spring is compressed and the coil spring bulges in the outer diameter direction, buckles, turns, falls, etc., interference between the coil spring and the inclined convex portion is suppressed.

  (4) Preferably, in the configuration of (3) above, the inclined surface may be an annular inclined surface that is continuous in an annular shape. According to this configuration, the inclined surfaces are continuous in all directions of 360 °. For this reason, when assembling the cell pressing assembly of the present invention, even if the ends of the plurality of coil springs are displaced in various directions, the displacement can be uniformly corrected to a predetermined position.

  (5) Preferably, in the configuration of the above (3), the inclined surface may be a partially inclined surface arranged with a predetermined angle apart from the central axis. According to this structure, the inclined surface which comprises an inclination convex part consists of a partial inclined surface spaced apart from each other. That is, the inclined surfaces of the inclined convex portions are separated from each other. For this reason, formation and arrangement of the inclined surface are facilitated, and as a result, formation and arrangement of the inclined convex portion are facilitated.

  (6) Preferably, in the configuration of (1), the positioning convex portion may be arranged on the facing surface of the cell side member. In a fuel cell, the cell stack expands and contracts due to temperature changes between operation and stop, and creep of the electrolyte membrane and electrodes due to long-term operation. The expansion or contraction is absorbed by the expansion or contraction of the elastic member and the accompanying tilting of the cell side member. For this reason, the relative arrangement | positioning angle of a cell side member and an elastic member is easy to change at the time of use of the cell press assembly of this invention, and before use. In this regard, the positioning convex portion is arranged on the cell side member of this configuration. For this reason, even if the relative arrangement | positioning angle of a cell side member and an elastic member changes, there is little possibility that an elastic member will shift | deviate with respect to a cell side member.

  (7) Preferably, in the configuration of the above (6), the elastic member is a spring group including a plurality of coil springs, and the end side member has a coil spring for positioning the coil spring. It is good to set it as the structure by which the recessed part for positioning in which an edge part is accommodated is arrange | positioned.

  Since a load is applied to the end side member from the outside, high load resistance and rigidity are required. For this reason, it is possible to make the thickness of the end side member thicker than the cell side member. In this case, if a positioning recess for accommodating the end of the coil spring is disposed in the end side member, at least a part of the thickened end side member is offset by the accommodation length of the coil spring. Become. That is, according to this configuration, even when the thickness of the end side member is increased, the cell pressing assembly itself can be prevented from increasing in thickness. Therefore, the cell pressing assembly can be downsized.

  Further, as described above, in the fuel cell, the cell stack expands and contracts due to a temperature change between operation and stop, or an electrolyte membrane or electrode creep due to long-term operation. In some cases, the stroke length of the coil spring is desired to be increased in order to improve the followability to expansion and contraction of the cell laminate. In this case, if the end portion of the coil spring is accommodated in the positioning recess, the thickness of the cell pressing assembly itself can be suppressed from increasing even if the length of the coil spring is increased. Thus, according to this configuration, the cell pressing assembly itself, and thus the fuel cell, can be reduced in size, which is advantageous when mounted on an automobile or the like.

  (8) Preferably, in the configuration of (1), at least one of the end-side member and the cell-side member on which the positioning convex portion is disposed is configured by a plate-like member, and the positioning convex portion is In addition, it may be configured to be formed by deformation of the plate-like member. According to this configuration, the positioning convex portion can be easily formed.

  Hereinafter, an embodiment of a cell pressing assembly for a fuel cell according to the present invention will be described.

<First embodiment>
First, the configuration of the fuel cell in which the cell battery pressure assembly of this embodiment is assembled will be described. FIG. 1 shows a side view of a polymer electrolyte fuel cell in which the cell pressing assembly for a fuel cell of this embodiment is assembled.

  As shown in FIG. 1, the polymer electrolyte fuel cell 9 includes a fuel cell cell pressing assembly (hereinafter abbreviated as “cell pressing assembly” as appropriate) 1, a cell stack 8, and a pair of insulating plates 91a. 91b, a pair of terminal plates 92a, 92b, a pair of end plates 90a, 90b, a pair of restraining plates 93a, 93b, a pair of tension plates 94a, 94b, and a pair of adjusting rods 6a, 6b. ing.

  Each of the pair of end plates 90a and 90b is made of an aluminum alloy and has a rectangular plate shape. The pair of end plates 90a and 90b are opposed to each other in substantially parallel with a predetermined interval in the stacking direction of the cell stack 8 to be described later. The end plate 90a is formed with a pair of adjusting rod through holes 900a and 900b (shown in cross section in FIG. 1 for convenience of explanation) spaced apart from each other by a predetermined interval. Thread grooves (not shown) are formed on the inner peripheral surfaces of the adjusting rod through holes 900a and 900b, respectively.

  Each of the pair of tension plates 94a and 94b is made of an aluminum alloy and has a rectangular plate shape. The pair of tension plates 94 a and 94 b are arranged to face each other substantially in parallel with a predetermined distance in the direction orthogonal to the stacking direction of the cell stack 8. The pair of tension plates 94a and 94b and the pair of end plates 90a and 90b are connected in a rectangular frame shape.

  The cell pressing assembly 1, the cell stack 8, the pair of insulating plates 91a and 91b, the pair of terminal plates 92a and 92b, the pair of restraining plates 93a and 93b, and the pair of adjusting rods 6a and 6b are accommodated in the rectangular frame. ing.

  The cell stack 8 is formed by stacking a large number of cells 80. The cell 80 is formed by holding an MEA (not shown) between separators (not shown). The cell 80 has a thin plate shape.

  Each of the pair of terminal plates 92a and 92b is made of copper and has a rectangular plate shape. The terminal plate 92 a is disposed on the end plate 90 a side of both sides in the stacking direction of the cell stack 8. On the other hand, the terminal plate 92b is disposed on the end plate 90b side.

  Each of the pair of insulating plates 91a and 91b is made of insulating resin and has a rectangular plate shape. The insulating plate 91a is disposed outside the terminal plate 92a in the stacking direction (the stacking direction of the cell stack 8). On the other hand, the insulating plate 91b is disposed outside the terminal plate 92b in the stacking direction and inside the end plate 90b in the stacking direction. In other words, the insulating plate 91b is interposed between the terminal plate 92b and the end plate 90b.

  Each of the pair of restraint plates 93a and 93b is made of urethane foam and has a rectangular plate shape. The pair of constraining plates 93 a and 93 b are disposed on both side surfaces of the cell stack 8 along the stacking direction of the cell stack 8. The restraint plate 93a is interposed between the tension plate 94a and the cell stack 8. On the other hand, the restraining plate 93 b is interposed between the tension plate 94 b and the cell stack 8.

  The adjusting rods 6a and 6b are made of steel and have a round bar shape. Screw threads are formed on the outer peripheral surfaces of the adjusting rods 6a and 6b. The adjusting rod 6a is inserted into the adjusting rod through hole 900a. The thread of the adjusting rod 6a is screwed with the thread groove of the adjusting rod through hole 900a. By turning the adjusting rod 6a, the screwing amount L of the adjusting rod 6a can be adjusted. Similarly, the adjustment rod 6b is inserted into the adjustment rod through hole 900b. The thread of the adjusting rod 6b is screwed with the thread groove of the adjusting rod through hole 900b. By turning the adjusting rod 6b, the screwing amount L of the adjusting rod 6b can be adjusted.

  The cell pressing assembly 1 is interposed between the end plate 90a and the insulating plate 91a. Further, the cell pressing assembly 1 is separated from the end plate 90a by the screwing amount L of the adjusting rods 6a and 6b.

  Next, the configuration of the fuel cell cell pressing assembly of this embodiment will be described. FIG. 2 shows a perspective exploded view of the cell pressing assembly. FIG. 3 shows a perspective combined view of the cell pressing assembly. FIG. 4 shows a cross-sectional view in the III-III direction of FIG. 3 and 4 show a state before assembling the cell pressing assembly and then assembling the polymer electrolyte fuel cell. As shown in FIGS. 2 to 4, the cell pressing assembly 1 includes an end side member 2, a cell side member 4, and a spring group 3.

  The spring group 3 includes a large number of coil springs 30 made of spring steel. A large number of coil springs 30 are regularly arranged. Before the assembly to the polymer electrolyte fuel cell 9, the coil spring 30 is in a substantially natural length state.

  The end side member 2 is made of an aluminum alloy and has a rectangular plate shape. The end side member 2 is located above the spring group 3 (in the direction of the end plate 90a in FIG. 1). The vertical direction in FIGS. 2 to 10 corresponds to the stacking direction of the cell stack 8 in FIG. ). A large number of end-side recesses 22 are formed on the lower surface of the end-side member 2, that is, on the facing surface (end-side facing surface) 26 facing the cell-side member 4. The end-side recess 22 is formed so as to correspond to each of the many coil springs 30. Therefore, one coil spring 30 is accommodated in one end-side recess 22. The end recess 22 houses the upper end of the coil spring 30. The end side recess 22 is included in the positioning recess of the present invention.

  On the other hand, a pair of rod receiving members 28 a and 28 b are arranged on the upper surface of the end side member 2. Each of the rod receiving members 28a and 28b is made of steel and has a disk shape with a slightly raised center. The rod receiving members 28a and 28b are fixed to the upper surface of the end side member 2 by screws. The adjusting rod 6a shown in FIG. 1 contacts the rod receiving member 28a, and the adjusting rod 6b shown in FIG. 1 contacts the rod receiving member 28b.

  Two guide rod through holes 21 are formed in the vicinity of a pair of opposing short sides of the end side member 2. That is, a total of four guide rod through holes 21 are arranged. The guide rod through hole 21 has a stepped columnar shape whose diameter decreases from the upper side to the lower side. The step functions as a stopper for the head of a guide rod 43 described later.

  The cell side member 4 includes a positioning member 4a and a reinforcing member 4b. The positioning member 4 a is disposed below the spring group 3. The reinforcing member 4b is disposed below the positioning member 4a. Note that the insulating plate 91a shown in FIG. 1 is disposed below the reinforcing member 4b.

  The reinforcing member 4b is made of an aluminum alloy and has a rectangular plate shape. Two guide rod fixing holes 42b are formed in the vicinity of a pair of opposing short sides of the reinforcing member 4b. That is, a total of four guide rod fixing holes 42b are arranged. A thread groove (not shown) is formed on the inner peripheral surface of the guide rod fixing hole 42b. A total of four guide rods 43 are screwed to the reinforcing member 4b. The guide rod 43 will be described in detail later. In addition, three bolt fixing recesses 41b are provided on the upper surface of the upper surface of the reinforcing member 4b near the pair of opposing long sides. That is, a total of six bolt fixing recesses 41b are arranged.

  The positioning member 4a is made of an aluminum alloy and has a rectangular thin plate shape. The positioning member 4 a is disposed below the spring group 3. A large number of inclined convex portions 40a are regularly formed on the upper surface of the positioning member 4a, that is, the opposing surface (hereinafter referred to as “cell-side opposing surface”) 46 facing the end side member 2. The inclined convex portion 40 a is formed so as to correspond to each of the many coil springs 30. One inclined convex portion 40 a is accommodated at the lower end of one coil spring 30. Each inclination convex part 40a is opposed to the above-mentioned end side crevice 22 in the up-and-down direction, respectively. The shape and the like of the inclined convex portion 40a will be described in detail later.

  Three bolt through holes 41a are formed in the vicinity of the pair of long sides facing the positioning member 4a. That is, a total of six bolt through holes 41a are arranged. The bolt 45 passes through the bolt through hole 41a and is screwed into the bolt fixing recess 41b. That is, the positioning member 4a is fixed to the reinforcing member 4b by the bolt 45.

  Two nut fastening holes 42a are formed in the vicinity of a pair of opposing short sides of the positioning member 4a. That is, a total of four nut fastening holes 42a are arranged. As described above, the guide rod 43 is screwed to the reinforcing member 4b. Each of the guide rods 43 is made of steel and has a bolt shape. The guide rod 43 has a head with a hexagonal hole. A screw thread is formed on the lower outer peripheral surface of the guide rod 43. The lower end of the guide rod 43 penetrates the guide rod through hole 21 of the end side member 2 from the upper side to the lower side, passes through the nut fastening hole 42a of the positioning member 4a, and enters the guide rod fixing hole 42b of the reinforcing member 4b. It is fixed. Specifically, the screw rod of the guide rod 43 and the screw groove of the guide rod fixing hole 42b are screwed together, whereby the lower end of the guide rod 43 is accommodated and fixed in the guide rod fixing hole 42b. Further, a nut 44 is screwed onto an upper portion of the outer periphery of the guide rod 43 above the nut fastening hole 42a. The nut 44 regulates the screwing amount of the lower end of the guide rod 43 with respect to the guide rod fixing hole 42b. The head of the guide rod 43 is disposed above the step of the guide rod through hole 21 of the end side member 2. Separation of the end side member 2 and the cell side member 4 is suppressed by the head portion of the guide rod 43 being caught by the step. The head portion of the guide rod 43 can protrude upward from the guide rod through hole 21 when the end side member 2 and the cell side member 4 approach each other.

  In a state in which the cell pressing assembly 1 is assembled to the polymer electrolyte fuel cell 9 (see FIG. 1 above), the end side member 2 is subjected to the elastic force of the spring group 3 by pressing from the adjusting rods 6a and 6b. It moves in the cell side member 4 direction while resisting. The cell side member 4 is urged toward the cell laminated body 8 by the spring group 3 and presses the cell laminated body 8. Thereby, the space | interval of the end side member 2 and the cell side member 4 becomes narrower than an assembly | attachment. As described above, the end side member 2 and the cell side member 4 are connected so as to be close to each other and to generate an elastic force in the spring group 3.

  Next, the configuration of the inclined convex portion 40a will be described in detail. FIG. 5 is an enlarged perspective view of the inclined convex portion of the cell side member of the cell pressing assembly of the present embodiment. FIG. 6 shows an enlarged view inside the dotted line frame IV in FIG. As shown in FIGS. 5 and 6, the inclined convex portion 40 a includes a pair of inclined claws 400 a. The pair of inclined claws 400 a are accommodated on the inner peripheral side of the lower end of the coil spring 30. The inclined claw 400a has a rectangular plate shape. The inclined claw 400a is formed integrally with the positioning member 4a. The pair of inclined claws 400 a are disposed so as to face each other at approximately 180 ° with the central axis O of the coil spring 30 as the center. The pair of inclined claws 400a protrude upward from the cell-side facing surface 46 while approaching each other. In other words, the pair of inclined claws 400a protrude upward in an “eight” shape so as to approach the central axis O. Partially inclined surfaces 401a are respectively disposed on the outer surfaces of the pair of inclined claws 400a. The lower end of the coil spring 30 is in contact with a portion (the root portion of the inclined claw 400a) connected to the partial inclined surface 401a on the cell-side facing surface 46.

  Next, a method for assembling the fuel cell cell pressing assembly of this embodiment will be briefly described. The method for assembling the fuel cell cell pressing assembly of the present embodiment includes an end side member arranging step, a spring group arranging step, and a cell side member arranging step.

  In the end side member arranging step, the end side member 2 is arranged in a horizontal state so that the end side concave portion 22 faces upward. In the spring group arranging step, the spring group 3 is erected on the end side member. At this time, the lower end of the coil spring 30 (corresponding to the upper end of FIG. 4) is accommodated in the end-side recess 22 of the end-side member 2. In the cell side member arrangement step, the cell side member 4 is arranged above the spring group 3. At this time, the inclined convex portion 40a of the cell side member 4 is relatively accommodated on the inner peripheral side of the upper end of the coil spring 30 (corresponding to the lower end of FIG. 4). Thus, the cell pressing assembly 1 of this embodiment is assembled.

  Next, the effect of the fuel cell cell pressing assembly of this embodiment will be described. According to the cell pressing assembly 1 of the present embodiment, when the cell pressing assembly 1 is assembled, the coil spring 30 can be easily positioned.

  That is, the end-side concave portion 22 is disposed in the end-side member 2. For this reason, in the said end side member arrangement | positioning process, positioning of the lower end (equivalent to the upper end of previous FIG. 4) of the coil spring 30 can be performed easily.

  Further, an inclined convex portion 40 a is arranged on the positioning member 4 a of the cell side member 4. For this reason, in the said cell side member arrangement | positioning process, positioning of the upper end (equivalent to the lower end of previous FIG. 4) of the coil spring 30 can be performed easily. More specifically, even if the upper end of the coil spring 30 is inclined due to its own weight or the like immediately after the spring group arranging step (even if it is not erected substantially vertically), the partial inclined surface 401a of the inclined claw 400a is a coil spring. The upper end of the inclined coil spring 30 can be corrected to a substantially vertical state by sliding contact with the inner peripheral surface of the upper end of 30 (that is, the partial inclined surface 401a guides the inner peripheral surface of the upper end of the coil spring 30). For this reason, the upper end of the coil spring 30 (corresponding to the lower end of FIG. 4) can be easily positioned. Thus, according to the cell pressing assembly 1 of this embodiment, the cell pressing assembly 1 can be easily assembled.

  Further, after the cell pressing assembly 1 is assembled, the upper end of the coil spring 30 is held by the end-side recess 22 from the outer peripheral side. And the lower end of the coil spring 30 is hold | maintained by the inclination convex part 40a from the inner peripheral side. That is, the coil spring 30 is held by two portions spaced apart in the vertical direction. Accordingly, it is possible to suppress the displacement of the coil spring 30 during conveyance and use.

  Further, according to the cell pressing assembly 1 of the present embodiment, one coil spring 30 is held with respect to the pair of end-side concave portions 22 and the inclined convex portions 40a. For this reason, even when many coil springs 30 are arranged, the individual coil springs 30 can be positioned without interfering with each other. Therefore, when the cell pressing assembly 1 is assembled, the coil spring 30 can be positioned more easily. Further, even after assembly, the displacement of the coil spring 30 is further suppressed.

  Moreover, according to the cell pressing assembly 1 of the present embodiment, the end-side recess 22 has a cylindrical shape. The inner diameter of the end-side recess 22 is substantially the same as the outer diameter of the coil spring 30. For this reason, the coil spring 30 can be stably disposed in the end-side recess 22. Moreover, the shape of the end side recessed part 22 is simple. For this reason, formation of the end side recessed part 22 is easy.

  Moreover, according to the cell pressing assembly 1 of this embodiment, the inclined convex part 40a is comprised from a pair of inclined nail | claw 400a. The pair of inclined claws 400a is formed by first forming an H-shaped hole in the positioning member 4a (see FIG. 5), and then raising the portion corresponding to the inclined claw 400a at the edge of the hole from the cell-side facing surface 46. Is done. In this manner, the inclined convex portion 40a can be easily formed simply by deforming the plate-like positioning member 4a.

  Further, according to the cell pressing assembly 1 of the present embodiment, the coil spring 30 is positioned by the end side recess 22 formed in the end side member 2 and the inclined protrusion 40a formed in the cell side member 4. be able to. For this reason, there is little need to arrange | position a guide member etc. for positioning the coil spring 30 separately. Therefore, the number of parts can be reduced.

  Further, according to the cell pressing assembly 1 of the present embodiment, since the upper end of the coil spring 30 is accommodated in the end-side recess 22, the cell pressing assembly having the coil spring 30 of the same length and not having the end-side recess 22. In comparison with the above, the thickness of the cell pressing assembly 1 (the thickness in the stacking direction of the cell stack 8 in FIG. 1) can be reduced by the amount of the accommodation length of the coil spring 30. Therefore, even when the end side member 2 and the cell side member 4 are thick, the cell pressing assembly 1 can be downsized.

  In the cell pressing assembly 1 of the present embodiment, members made of aluminum alloy such as the end side member 2 and the cell side member 4 are frequently used. Therefore, it is possible to reduce the weight of the cell pressing assembly 1 and thus the polymer electrolyte fuel cell 9. In addition, since the spring group 3 including a large number of coil springs 30 is employed as the elastic member, it is easy to handle and it is easy to ensure a desired stroke length according to the expansion and contraction of the cell stack 8. Furthermore, the cell pressing assembly 1 of the present embodiment is modularized by an end side member 2 and a cell side member 4 that are connected to each other so that an elastic force is generated in the spring group 3. For this reason, it is possible to easily manufacture and replace the polymer electrolyte fuel cell 9.

<Second embodiment>
The difference between this embodiment and 1st embodiment is a point by which the cone-shaped inclination convex part is arrange | positioned at the cell side opposing surface. Therefore, only the differences will be described here. FIG. 7 is an enlarged perspective view of the inclined convex portion of the cell side member of the cell pressing assembly of the present embodiment. In addition, about the site | part corresponding to FIG. 5, it shows with the same code | symbol. FIG. 8 shows an enlarged partial cross-sectional view of the cell pressing assembly. FIG. 8 corresponds to FIG. 8, parts corresponding to those in FIG. 6 are denoted by the same reference numerals.

  As shown in FIGS. 7 and 8, the inclined convex portion 40a has a conical shape whose diameter is reduced upward. A tapered annular inclined surface 402a is disposed on the side surface of the inclined convex portion 40a. The annular inclined surface 402a is disposed over the entire circumference of the inclined convex portion 40a. The inner diameter of the lower end of the coil spring 30 is substantially the same as the outer diameter of the bottom of the inclined convex portion 40a. The positioning member 4a is produced by casting. The inclined convex part 40a is formed simultaneously with the casting.

  The cell pressing assembly of the present embodiment has the same operational effects as the cell pressing assembly of the first embodiment. Further, the inclined convex portion 40a of the cell pressing assembly of the present embodiment is provided with an annular inclined surface 402a that is continuous by 360 °. For this reason, even when the upper ends of the many coil springs 30 are inclined in various directions at the time of assembling the cell pressing assembly (for example, at the cell side member arranging step of the first embodiment), the inclination is uniformly changed. It can be corrected to a substantially vertical state. Moreover, the inclined convex part 40a is formed simultaneously with the casting of the positioning member 4a. Thus, the inclined convex part 40a can be formed relatively easily by the deformation of the plate-like positioning member 4a.

<Third embodiment>
The difference between this embodiment and 1st embodiment is a point by which the ring-shaped inclination convex part is arrange | positioned at the cell side opposing surface. Therefore, only the differences will be described here. FIG. 9 is an enlarged perspective view of the inclined convex portion of the cell side member of the cell pressing assembly of the present embodiment. In addition, about the site | part corresponding to FIG. 5, it shows with the same code | symbol. FIG. 10 shows an enlarged partial cross-sectional view of the cell pressing assembly. FIG. 10 corresponds to FIG. 10, parts corresponding to those in FIG. 6 are denoted by the same reference numerals.

  As shown in FIGS. 9 and 10, the inclined convex portion 40 a has a substantially perfect ring shape. An annular inclined surface 403a is disposed on the outer peripheral surface of the inclined convex portion 40a. The annular inclined surface 403a is disposed over the entire outer peripheral surface of the inclined convex portion 40a. Further, the annular inclined surface 403 a is inclined so as to approach the central axis O of the coil spring 30. That is, the annular inclined surface 403a has a taper shape with a diameter decreasing upward. The inner diameter of the lower end of the coil spring 30 is substantially the same as the outer diameter of the bottom of the inclined convex portion 40a. The inclined convex portion 40a is formed by embossing with a punch (not shown) from the lower surface side of the positioning member 4a (for this reason, as shown in FIG. 10, the positioning member 4a is arranged with the inclined convex portion 40a. Only the part protrudes upward and is curved.)

  The cell pressing assembly of the present embodiment has the same operational effects as the cell pressing assembly of the first embodiment. Further, the inclined convex portion 40a of the cell pressing assembly according to the present embodiment is provided with an annular inclined surface 403a continuous with 360 °. For this reason, even when the upper ends of the many coil springs 30 are inclined in various directions at the time of assembling the cell pressing assembly (for example, at the cell side member arranging step of the first embodiment), the inclination is uniformly changed. It can be corrected to a substantially vertical state. Further, the inclined convex portion 40a is formed by embossing. For this reason, a large number of inclined convex portions 40a can be formed at a time by deformation of the plate-like positioning member 4a.

<Fourth embodiment>
The difference between this embodiment and 3rd embodiment is a point by which the ring-shaped convex part is arrange | positioned at the outer peripheral side of a coil spring. Therefore, only the differences will be described here. In FIG. 11, the fragmentary sectional enlarged view of the cell press assembly of this embodiment is shown. FIG. 11 corresponds to FIG. 11, parts corresponding to those in FIG. 10 are denoted by the same reference numerals. In FIG. 11, the coil spring 30 on the back side of the drawing is omitted from the III-III cross section of FIG. 3.

  As shown in FIG. 11, the ring-shaped convex part 47a has a substantially perfect ring shape. An inner peripheral inclined surface 470a is disposed on the inner peripheral surface of the ring-shaped convex portion 47a. The outer diameter of the lower end of the coil spring 30 is substantially the same as the inner diameter of the bottom of the ring-shaped convex portion 47a. The ring-shaped convex portion 47a is formed by embossing with a punch (not shown) from the lower surface side of the positioning member 4a (for this reason, as shown in FIG. 11, the positioning member 4a is formed of a ring-shaped convex portion. Only the portion where 47a is disposed protrudes and curves upward.

  The cell pressing assembly of the present embodiment has the same operational effects as the cell pressing assembly of the first embodiment. More specifically, immediately after the spring group arranging step of the first embodiment, even if the upper end of the coil spring 30 is inclined due to, for example, its own weight or the like (even if it is not erected substantially vertically), When the inner peripheral inclined surface 470a is in sliding contact with the outer peripheral surface of the upper end of the coil spring 30 (that is, when the inner peripheral inclined surface 470a guides the outer peripheral surface of the upper end of the coil spring 30), the upper end of the inclined coil spring 30 is substantially vertical. Can be corrected. For this reason, the upper end of the coil spring 30 (corresponding to the lower end of FIG. 4) can be easily positioned. Thus, according to the cell pressing assembly of this embodiment, the cell pressing assembly can be easily assembled.

  Further, after the cell pressing assembly is assembled, the upper end of the coil spring 30 is held by the end-side recess 22 from the outer peripheral side. And the lower end of the coil spring 30 is hold | maintained by the ring-shaped convex part 47a from the outer peripheral side. That is, the coil spring 30 is held by two portions spaced apart in the vertical direction. Accordingly, it is possible to suppress the displacement of the coil spring 30 during conveyance and use.

  Moreover, the inner peripheral side inclined surface 470a which continues 360 degrees is arrange | positioned at the ring-shaped convex part 47a of the cell press assembly of this embodiment. For this reason, even when the upper ends of the many coil springs 30 are inclined in various directions at the time of assembling the cell pressing assembly (for example, at the cell side member arranging step of the first embodiment), the inclination is uniformly changed. It can be corrected to a substantially vertical state. Moreover, the ring-shaped convex part 47a is formed by stamping. For this reason, many ring-shaped convex parts 47a can be formed at once.

<Fifth embodiment>
The difference between this embodiment and the second embodiment is that the shape of the inclined convex portion, that is, the inclined convex portion is configured by combining a conical portion and a cylindrical portion. Therefore, only the differences will be described here. FIG. 12 is an enlarged perspective view of the inclined convex portion of the cell side member of the cell pressing assembly of the present embodiment. In addition, about the site | part corresponding to FIG. 7, it shows with the same code | symbol.

  As shown in FIG. 12, the inclined convex portion 40a includes a conical portion 404a and a cylindrical portion 405a. The conical portion 404a is reduced in diameter toward the upper side. A tapered annular inclined surface 402a is disposed on the side surface of the conical portion 404a. The annular inclined surface 402a is disposed over the entire circumference of the conical portion 404a. The cylindrical portion 405a is disposed below the conical portion 404a. The inner diameter of the lower end of the coil spring 30 is substantially the same as the outer diameter of the bottom (the cylindrical portion 405a) of the inclined convex portion 40a.

  The cell pressing assembly of the present embodiment has the same effects as the cell pressing assembly of the second embodiment. Further, the inclined convex portion 40 a of the cell pressing assembly of the present embodiment has a cylindrical portion 405 a that stands up in the direction of the central axis O of the coil spring 30. For this reason, even when the upper ends of the many coil springs 30 are inclined in various directions at the time of assembling the cell pressing assembly (for example, at the cell side member arranging step of the first embodiment), the cylindrical portion 405a is mainly used. When the side surface is in sliding contact with the outer peripheral surface of the upper end of the coil spring 30 (that is, the side surface of the cylindrical portion 405a guides the outer peripheral surface of the upper end of the coil spring 30), the upper end of the inclined coil spring 30 can be corrected to a substantially vertical state. it can. For this reason, the upper end of the coil spring 30 (corresponding to the lower end of FIG. 4) can be positioned more reliably.

<Others>
The embodiments of the fuel cell cell pressing assembly of the present invention have been described above. However, the fuel cell cell pressing assembly according to the present invention is not limited to the above-described embodiment, and can be variously modified and improved by those skilled in the art without departing from the gist of the present invention. Can be implemented.

  For example, in the said embodiment, the convex part for positioning (inclination convex part) was arrange | positioned to the cell side member. However, the positioning convex portion may be formed on the end side member. Moreover, you may form in both the members of a cell side member and an end side member. Further, the shape and size of the positioning convex portion and the arrangement method (inner peripheral side or outer peripheral side, etc.) with respect to coil springing are not particularly limited. For example, positioning convex portions may be arranged on the inner peripheral side and the outer peripheral side of the coil spring. As the inclined convex portion, for example, a partial cone shape, a pyramid shape, a partial pyramid shape, a cylindrical shape, a prism shape, a partial spherical shape, a partial elliptic spherical shape, or the like can be adopted. When a pyramidal or partial pyramidal inclined convex portion is adopted instead of the conical inclined convex portion of the second embodiment, the maximum length of the bottom diagonal line is substantially the same as the inner diameter of the end of the coil spring. It is desirable to make it.

  Moreover, in the said embodiment, the cell side member was made into the 2 member structure which consists of a positioning member and a reinforcement member. The material of the positioning member and the reinforcing member is not particularly limited, and various materials such as steel and stainless steel can be adopted in addition to the aluminum alloy. On the other hand, you may comprise a cell side member by a single member. This reduces the number of parts.

  Moreover, in the said embodiment, the recessed part for positioning (end side recessed part) was formed so that it might correspond to a coil spring on a one-to-one basis. However, the number and arrangement of the positioning recesses are not particularly limited. That is, the positioning recess does not have to correspond one-to-one with the coil spring. For example, several coil springs may be accommodated together in one positioning recess. If it carries out like this, the shape of the end side member etc. which form the recessed part for positioning will become easy.

  Moreover, in the said embodiment, the spring group which consists of many coil springs as an elastic member was employ | adopted. However, the type of elastic member is not particularly limited. For example, a disc spring, a low elasticity sponge, rubber, elastic resin, or the like may be employed. Further, the number, arrangement, material, size, and the like of the coil springs constituting the spring group are not particularly limited. The number, arrangement, material, size, and the like of the coil springs may be appropriately determined according to the fastening load set for the cell stack, the load characteristics of the coil springs, and the like. For example, examples of the material of the coil spring include stainless steel, titanium and the like in addition to spring steel. According to the cell pressing assembly of the present invention, the coil spring can be easily positioned regardless of the number of coil springs. Therefore, it is particularly suitable for use in a cell pressing assembly having a large number of coil springs (for example, 100 or more).

  Moreover, in the said embodiment, the aluminum alloy was employ | adopted as a material of an end side member and a cell side member. However, the material of each member is not limited to this, and each member may be composed of other materials such as stainless steel. For example, at least one of the end side member and the cell side member may be made of a light alloy other than an aluminum alloy. For example, at least one of the above members may be made of a magnesium alloy having a specific gravity of about 1.7 to 2.0 or a titanium alloy having a specific gravity of about 4.5.

  Moreover, in the said embodiment, the bolt-shaped guide rod which has a hexagonal socket head was used. However, the shape of the guide rod is not particularly limited. For example, a hexagon bolt or the like may be used as the guide rod. The material of the guide rod is not particularly limited, and various materials such as steel, stainless steel, and chromium molybdenum steel can be employed.

  Further, the configuration of the fuel cell is not limited to the above embodiment. For example, the fuel cell cell pressing assemblies of the present invention may be disposed on both sides in the stacking direction of the cell stack. Moreover, in the said embodiment, although the end side member was pressed with two adjustment rods, the method of pressing an end side member, such as the number of adjustment rods, is not specifically limited.

It is a side view of the polymer electrolyte fuel cell with which the cell press assembly of the first embodiment of the present invention was assembled. It is a perspective exploded view of the cell press assembly of the first embodiment of the present invention. It is a perspective combined view of the cell pressing assembly. It is the III-III direction sectional drawing of FIG. It is a perspective enlarged view of the inclination convex part of the cell side member of the cell press assembly. FIG. 5 is an enlarged view in a dotted line frame IV in FIG. 4. It is a perspective enlarged view of the inclination convex part of the cell side member of the cell press assembly of 2nd embodiment of this invention. It is a partial cross-section enlarged view of the cell pressing assembly. It is a perspective enlarged view of the inclination convex part of the cell side member of the cell press assembly of 3rd embodiment of this invention. It is a partial cross-section enlarged view of the cell pressing assembly. It is a partial cross-section enlarged view of the cell pressing assembly of the fourth embodiment of the present invention. It is a perspective enlarged view of the inclination convex part of the cell side member of the cell press assembly of 5th embodiment of this invention.

Explanation of symbols

1: Cell pressing assembly 2: End side member 21: Guide rod through hole 22: End side recess (positioning recess)
26: End side facing surface (facing surface) 28a, 28b: Rod receiving member 3: Spring group (elastic member) 30: Coil spring 4: Cell side member 4a: Positioning member 4b: Reinforcing member 40a: Inclined convex portion 400a: Inclined Claw 401a: Partially inclined surface 402a: Annular inclined surface 403a: Annular inclined surface 404a: Conical portion 405a: Column portion 41a: Bolt through hole 41b: Bolt fixing recess 42a: Nut fastening hole 42b: Guide rod fixing hole 43: Guide rod 44 : Nut 45: Bolt 46: Cell side facing surface (facing surface)
47a: ring-shaped convex part (positioning convex part) 470a: inner peripheral inclined surface 5: guide plate 50: coil spring holding hole 51: bolt through hole 52: nut fastening hole 6a, 6b: adjusting rod 8: cell laminate 80: Cell 9: Polymer electrolyte fuel cell 90a, 90b: End plate 91a, 91b: Insulating plate 92a, 92b: Terminal plate 93a, 93b: Restraint plate 94a, 94b: Tension plate 900a, 900b: Adjust rod through hole

Claims (8)

An end side member to which a load is applied from the outside;
A cell-side member disposed opposite to the end-side member, and disposed closer to the cell stack than the end-side member;
An elastic member interposed between the end side member and the cell side member and capable of storing elastic energy for pressing the cell stack;
A cell pressing assembly for a fuel cell comprising:
The end-side member and the cell-side member are connected to each other so as to hold the elastic member, and each has a facing surface facing each other,
A cell pressing assembly for a fuel cell, wherein a positioning convex portion for positioning the elastic member is disposed on at least one of the pair of facing surfaces.   The cell pressing assembly for a fuel cell according to claim 1, wherein the elastic member is a spring group including a plurality of coil springs. The positioning convex portion positions the end of the coil spring from the inner peripheral side,
The cell pressing assembly for a fuel cell according to claim 2, wherein the cell pressing assembly is an inclined convex portion having an inclined surface that is inclined so as to approach the central axis of the coil spring.   The cell pressing assembly for a fuel cell according to claim 3, wherein the inclined surface is an annular inclined surface continuous in an annular shape.   4. The fuel cell cell pressing assembly according to claim 3, wherein the inclined surface is a partially inclined surface that is spaced apart from each other by a predetermined angle about the central axis. 5.   The cell pressing assembly for a fuel cell according to claim 1, wherein the positioning convex portion is disposed on the facing surface of the cell side member. The elastic member is a spring group composed of a plurality of coil springs,
The cell pressing assembly for a fuel cell according to claim 6, wherein the end side member is provided with a positioning concave portion in which an end portion of the coil spring is accommodated in order to position the coil spring. At least one of the end side member and the cell side member on which the positioning convex portion is arranged is configured by a plate-like member,
The cell pressing assembly for a fuel cell according to claim 1, wherein the positioning convex portion is formed by deformation of the plate member.

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