JP6363433B2 - Gasket for laminated member - Google Patents

Description

  The present invention relates to a gasket which is a kind of sealing device related to sealing technology, and more particularly to a gasket for a laminated member in which a gasket main body made of a rubber-like elastic body is mounted in a gasket mounting groove provided on a plane of the laminated member. . The gasket of the present invention is used, for example, in the field of fuel cell seals, or in the field of other flat fixed seals (such as heat exchangers).

  For example, the fuel cell stack is mainly composed of an electrode reaction part such as MEA (Membrane Electrode Assembly) and a separator for partitioning an anode and a cathode. As the electrolyte membrane in the electrode reaction part, a fluorine-based solid polymer membrane or the like is mainly used, and proton conductivity is required. The separator plays an important role in forming a flow path for supplying fluid to the electrolyte membrane and conducting electrons generated on the anode side.

  On the other hand, the seal for the fuel cell serves to seal each fluid, for example, air containing hydrogen gas or oxygen, or a coolant for cooling the stack, from flowing out / inflowing to the outside of the stack or other fluid areas. . These fuel cells are generally composed of a plurality of cells and stacked from a small power source of several tens of watts to a power source for automobiles of 100 kW. For example, in the fuel cell, for example, on the fuel side, a fuel gas containing hydrogen atoms such as hydrogen gas and methanol is supplied to the reaction surface of each cell from the supply communication hole, and the exhaust communication channel is provided. It is discharged out of the stack through the hole. At this time, at the reaction surface, at least a communication hole for other fluid or a seal that does not leak out of the system is necessary. Similarly, the oxygen or air side, cooling water or refrigerant side has the same configuration. Water electrolysis has the same structure, and the hydrogen generation surface and the oxygen generation surface need to be sealed with respective fluids.

  These laminated members are composed of an electrolyte membrane that conducts protons and a conductive plate such as a separator that conducts extracted electrons. A gasket for sealing each fluid is attached to the electrolyte membrane side or the conductive plate side. For example, when the MEA is sandwiched between conductive plates, a plate having a fuel side channel and a plate having an air or oxygen channel are used. Cooling water or refrigerant is supplied between these plates. In order to seal these fluids, a sealing material such as a rubber gasket or an adhesive is disposed in each layer.

  When a compression seal typified by a rubber gasket is used as the plate seal, a laminated stack for automobiles or stationary use is provided with a bottomed gasket mounting groove on the plane of the separator, and a rubber gasket is provided in the gasket mounting groove. Mounting is generally performed (see Patent Document 1).

JP-A-7-263004

  However, in a fuel cell stack, generally, a carbon separator is laminated with a thin plate of about 0.5 to 2 mm, and a metal separator is laminated with a thickness of about 0.1 to 0.5 mm. Further, these end portions are stacked by a plate having a thickness of approximately several mm or more such as a current collecting plate or an insulating plate. Each plate layer requires a gasket for sealing an anode fluid such as hydrogen gas, a cathode fluid such as air, and a refrigerant.

  On the other hand, the usage environment may be as low as −40 ° C. at low temperatures and up to about 100 ° C. at high temperatures. Although it is necessary to seal a wide temperature range, deformation of the laminated portion occurs in the stack as these temperatures are varied. In particular, thin members such as MEAs and separators are likely to warp and swell in the stacking direction due to temperature fluctuations. On the other hand, a thick member such as a current collector plate or an insulating plate has little change in the stacking direction.

  In other words, a gap is likely to occur between a thin member such as a separator and a thick member such as a current collector plate, which causes leakage. Depending on the size of the warp, a clearance several times larger than the height direction clearance of the normal tightening portion may occur. In order to solve this, a gasket having a relatively large cross-sectional shape is required, but due to the demand for downsizing of the mounting groove and the stack, a sufficient gasket space cannot be taken, which is a problem.

  In view of the above, the present invention is a laminated member capable of exhibiting sufficient sealing performance even if the gasket mounting groove for mounting the gasket is downsized and the sectional area of the gasket is downsized accordingly. An object is to provide a gasket.

  In order to achieve the above object, a laminated member gasket according to claim 1 of the present invention is a laminated member gasket in which a gasket body made of a rubber-like elastic body is mounted in a gasket mounting groove provided on a plane of the laminated member. The gasket body integrally includes a gasket base portion fitted in the mounting groove and a seal lip portion provided on a plane of the base portion, and the gasket lip portion is formed by laminating the laminated member. The mounting groove has an asymmetrical shape in the groove width direction so that the seal lip portion falls to the sealing fluid side when compressed in the thickness direction, and the attachment groove promotes the fall of the seal lip portion. Thus, the groove bottom surface of the mounting groove is inclined so that the groove depth gradually increases from the sealing fluid side to the anti-sealing fluid side.

  The gasket for a laminated member according to claim 2 of the present invention is the gasket for laminated member according to claim 1 described above, and acts as a fulcrum of the insulator on the lower surface of the gasket base portion of the gasket body when the seal lip portion falls. A bead-shaped projection is provided.

  In the gasket for a laminated member of the present invention having the above-described configuration, when the laminated member is laminated and the gasket main body is compressed in the thickness direction, the seal lip portion has its tip portion in contact with the other side of the lamination (adjacent laminated member), Furthermore, since the seal lip part is elastically deformed to fall to the sealing fluid side, and the direction in which the seal lip part falls is on the sealing fluid side, the higher the pressure on the sealing fluid side after mounting, the stronger the sealing lip part is pressed against the other side of the stack Function is demonstrated. Therefore, even if the cross-sectional area of the gasket body is not so large, sufficient sealing performance can be exhibited.

  In the present invention, the reason that the seal lip portion easily falls to the sealing fluid side is that the seal lip portion has an asymmetric shape in the groove width direction of the mounting groove, but the mounting groove further causes the seal lip portion to fall. The groove bottom surface of the mounting groove is inclined so that the groove depth gradually increases from the sealing fluid side to the anti-sealing fluid side for the purpose of promotion. Therefore, when the laminated members are laminated and the gasket body is compressed in the thickness direction, the gasket body as a whole is inclined to the deeper groove depth, and thus the seal lip portion tends to fall toward the sealing fluid.

  In addition, it may be possible to provide a bead-like projection that acts as a fulcrum of the insulator when the seal lip part falls on the lower surface of the gasket base in the gasket body. In this case, the inclination of the gasket body increases due to the action of the insulator. As a result, the fall of the seal lip portion also increases.

  The present invention has the following effects.

  That is, in the present invention, as described above, when the laminated member is laminated and the gasket main body is compressed in the thickness direction, the seal lip portion is elastically deformed so as to fall to the sealing fluid side, whereby the pressure on the sealing fluid side is high. The self-seal function is exerted so that the seal lip portion is strongly pressed against the other side of the lamination. Accordingly, even if the cross-sectional area of the gasket body is not so large, sufficient sealing performance can be exhibited. Moreover, since the groove bottom surface of the mounting groove is formed into an inclined surface, the inclination of the gasket main body is increased, so that the fall of the seal lip portion can be increased.

  Further, by providing a bead-like protrusion on the lower surface of the gasket base, this protrusion acts as a fulcrum of the insulator, so that the inclination of the gasket main body, and further the fall of the seal lip can be further increased. The fact that the seal lip part tends to collapse means that the seal lip part is strongly pressed against the other side of the lamination even when the tightening allowance associated with the lamination of the laminated members is small, so that excellent sealing performance can be exhibited.

The top view of the gasket for laminated members which concerns on the Example of this invention FIG. 2 is an enlarged sectional view taken along line CC in FIG. 1 and a partially enlarged sectional view of the gasket. Partial sectional view showing a state where the gasket is laminated

The present invention includes the following embodiments.
(1) A gasket that has a lip shape that is asymmetric and has a structure in which the lip is easy to fall, and even when the tightening margin is small, the gasket that has been pushed down by the internal pressure is pressed against the seal member for sealing. The groove bottom of the mounting member fitted to the gasket bottom portion on the opposite side is inclined so as to ensure the fall or to prevent it from falling opposite to the assumed side.
(2) A gasket having a left-right asymmetric cross-sectional shape, in which the gasket collapses during compression and is sealed by internal pressure, and the gasket mounting groove bottom is inclined. Further, the gasket cross-sectional shape facing the inclined portion has a bead.
(3) There is a gap between the bottom of the mounting groove and the bottom of the gasket.
(4) The base side surface of the gasket is supported by the side wall of the mounting groove. Only the lip tip buckles.
(5) The conventional bottom flat leaked at a compression ratio of 14%, but the leakage stopped by attaching an angle of 3% to the groove bottom.

  Next, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows an entire plane of a laminated member gasket 11 according to an embodiment of the present invention. The laminated member gasket 11 is a gasket main body made of a rubber-like elastic body in a gasket mounting groove provided on the plane of the laminated member. Is the one that is attached.

  The laminated member is specifically a fuel cell separator 21 having a predetermined thickness dimension and a flat rectangular shape, and a flow path region 22 through which a fluid such as fuel gas flows is provided in the center of the flat surface. A fluid supply manifold hole 23 for supplying fluid to the flow channel region 22, a fluid discharge manifold hole 24 for discharging fluid from the flow channel region 22, and a manifold hole 25 of another system are provided at the corners. The fluid flowing from the fluid supply manifold hole 23 to the fluid discharge manifold hole 24 via the flow path region 22 does not leak to the outside or flow into the manifold hole 25 of another system. The fluid supply manifold hole 23, the flow path region 22 and the fluid discharge manifold hole 24 are surrounded so that the fluid flowing through Gasket installation groove 26 is provided so as to surround the manifold holes 25 of the system individually, gasket body 31 is mounted in the mounting groove 26.

  FIG. 2 is an enlarged cross-sectional view taken along the line CC in FIG. 1. The left side of the drawing is a sealed fluid side A and the right side is an anti-sealed fluid side (atmosphere side) B. A gasket mounting groove 26 having a rectangular or substantially rectangular cross section is provided on the plane of the separator 21, and a gasket main body 31 made of a rubber-like elastic body is mounted in the mounting groove 26 without bonding.

  The gasket main body 31 integrally includes a gasket base portion 32 fitted into the mounting groove 26 and a seal lip portion 33 provided on the plane of the base portion 32.

  The base portion 32 has a horizontally long cross-sectional rectangular shape or a substantially rectangular shape having a lateral width equal to or substantially equal to the groove width of the mounting groove 26.

  The seal lip portion 33 is provided unevenly on the anti-sealing fluid side B on the plane of the base portion 32, and the cross-sectional shape thereof is a tapered triangular shape or a substantially triangular shape. Further, the seal lip portion 33 having a triangular section has a slope 33a on the sealing fluid side A and a slope 33b on the anti-sealing fluid side B. The slope 33a on the former sealing fluid side A is on the opposite side of the latter anti-sealing fluid side B. The slope is set steeper than the slope 33b. Therefore, the seal lip 33 is mounted so that the seal lip 33 is tilted toward the sealed fluid side A when the separator 21 is laminated and the gasket body 31 is compressed in the thickness direction (vertical direction in FIG. 1). The shape of the groove 26 is asymmetric in the groove width direction.

  The mounting groove 26 has a rectangular or substantially rectangular cross section as described above, and the groove depth extends from the sealing fluid side A to the anti-sealing fluid side B in order to promote the collapse of the seal lip 33. The groove bottom surface 26a of the mounting groove 26 has an inclined surface shape so as to be gradually deeper. Accordingly, a predetermined inclination angle θ toward the sealed fluid side A is set on the groove bottom surface 26a of the mounting groove 26, and this inclination angle θ is set to about 3 degrees, for example.

  In addition, a bead-shaped projection 34 that can act as a fulcrum of the insulator when the seal lip portion 33 is tilted is provided on the lower surface of the base portion 32 of the gasket main body 31. Are provided in parallel with each other.

FIG. 2 shows an initial mounting state before the gasket body 31 is compressed in the thickness direction. In this initial mounting state, the bead-shaped protrusions 34 provided on the lower surface of the base portion 32 are grooves of the mounting groove 26. Since it contacts the bottom surface 26 a, a predetermined interval t ₁ is provided between the groove bottom surface 26 a of the mounting groove 26 and the lower surface of the base portion 32.

Since the mounting groove 26 is inclined as described above, only the bead-shaped protrusion 34 on the sealed fluid side A side of the three bead-shaped protrusions 34 contacts the groove bottom surface 26 a of the mounting groove 26. In addition, a predetermined interval t ₂ is provided between the center bead-shaped protrusion 34 and the groove bottom surface 26 a of the mounting groove 26, and between the bead-shaped protrusion 34 on the anti-sealing fluid side B and the groove bottom surface 26 a of the mounting groove 26. predetermined interval t ₃ is also provided (although the drawing of convenience, t ₂ is not shown).

The size relationship between these intervals t ₁ , t ₂ , and t ₃ is t ₁ > t ₃ > t _2, and the intervals t ₁ , t ₂ , and t ₃ are all anti-sealing fluids of the gasket body 31. It is provided as a configuration for inclining to the side B.

  FIG. 3 shows a state in which the separator 21 is stacked from the initial mounting state of FIG. 2 and the gasket body 31 is compressed in the thickness direction. In this mounting / compressed state, the seal lip portion 33 has its tip 33c. Since it is elastically deformed so as to come into contact with the other party (adjacent separator) 41 and further fall down to the sealing fluid side A, and the direction in which the seal lip 33 is tilted is the sealing fluid side A, As the pressure P is higher, a self-seal function is exerted in which the seal lip 33 is more strongly pressed against the mating counterpart 41. Therefore, since the self-sealing function is exhibited in this way, even if the gasket space is small and the cross-sectional area of the gasket main body 21 is not so large, the gasket 11 can exhibit sufficient sealing performance.

In the laminated member gasket 11 having the above-described configuration, the seal lip portion 33 is easily tilted to the sealed fluid side A based on the following configuration.
That is, firstly, the seal lip portion 33 is asymmetric in the groove width direction of the mounting groove 26.
Second, the groove bottom surface 26a of the mounting groove 26 is inclined so that the groove depth gradually increases from the sealing fluid side A to the anti-sealing fluid side B.
Thirdly, a bead-shaped protrusion 34 that acts as a fulcrum of the insulator when the seal lip 33 falls down is provided on the lower surface of the gasket base 32 in the gasket body 31.

  Regarding the third point, when the separators 21 are stacked and the gasket main body 31 is compressed in the thickness direction, first, the gasket main body 31 is positioned on the right side of the figure with the bead-shaped protrusion 34 on the sealing fluid side A side as a fulcrum of the insulator. Inclined downward, the bead-shaped projection 34 at the center contacts the groove bottom surface 26 a of the mounting groove 26. Next, the gasket main body 31 is tilted to the lower right in the drawing with the central bead-shaped protrusion 34 as a fulcrum of the lever, and the bead-shaped protrusion 34 on the anti-sealing fluid side B contacts the groove bottom surface 26 a of the mounting groove 26. Next, the gasket main body 31 is inclined downward to the right in the figure with the bead-shaped protrusion 34 on the anti-sealing fluid side B as a fulcrum of the insulator, and the end of the anti-sealing fluid side B on the bottom surface of the base 32 is formed on the groove bottom surface 26 a of the mounting groove 26. Approach or approach the groove bottom surface 26a of the mounting groove 26.

  Accordingly, the three bead-shaped projections 34 sequentially act as the fulcrum of the insulator in this way, so that the gasket body 31 can be inclined in a stepwise and large manner, whereby the seal lip portion 33 is greatly increased toward the sealed fluid side A. Fall down.

  However, in the present invention, the number of bead-shaped protrusions 34 formed in this way is merely an example, and the number of bead-shaped protrusions 34 may be one, two, or four or more. It may be. Moreover, it is preferable to provide a predetermined gap width direction interval between the bead-shaped projection 34 and the end of the bottom surface of the base portion 32 on the anti-sealing fluid side B regardless of the number of the formation.

11 Gasket for laminated member 21 Separator (laminated member)
22 Flow path area 23, 24, 25 Manifold hole 26 Gasket mounting groove 26a Groove bottom 31 Gasket body 32 Base 33 Seal lip 33a, 33b Slope 33c Tip 34 Bead-shaped protrusion 41 Laminated mating part A Sealed fluid side B Anti Sealed fluid side

Claims (2)

A gasket for a laminated member in which a gasket main body made of a rubber-like elastic body is attached to a gasket mounting groove provided on a plane of the laminated member,
The gasket main body integrally includes a gasket base portion fitted in the mounting groove and a seal lip portion provided on a plane of the base portion,
The seal lip portion has an asymmetric shape in the groove width direction of the mounting groove so that when the laminated member is laminated and the gasket body is compressed in the thickness direction, the seal lip portion falls to the sealing fluid side,
Further, the mounting groove has an inclined surface on the bottom surface of the mounting groove so that the groove depth gradually increases from the sealing fluid side to the anti-sealing fluid side in order to promote the fall of the seal lip portion. A gasket for laminated members, characterized by comprising: In the gasket for laminated members according to claim 1,
A gasket for a laminated member, wherein a bead-shaped projection that acts as a fulcrum of an insulator when the seal lip portion falls is provided on a lower surface of a gasket base portion in the gasket main body.

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