JP5093554B2 - Gasket for fuel cell - Google Patents

Description

The present invention relates to a fuel cell gasket.
The present invention also relates to a fuel cell gasket useful as a seal for sealing between separators of a fuel cell.

Conventionally, as a gasket for a fuel cell, an integrally molded gasket made of an elastic body such as rubber and integrally molded with a separator, and a non-adhesive gasket sandwiched between separators are known.
Among these, as the non-adhesive type gasket, a flat plate is known.
However, this type of gasket has a problem that the reaction force is high because there is no escape of rubber, and as a result, a high tightening force is required.

In order to improve this point, a fuel cell gasket shown in FIG. 4 has been proposed.
The inner peripheral surface collar portion 103 is provided on the inner peripheral side of the seal portion 500 having a circular cross section, and the outer peripheral surface collar portion 104 is provided on the outer peripheral side.
However, not only is it difficult to sufficiently reduce the reaction force, but when this kind of fuel cell gasket is mounted and compressed, the gasket collapses, causing a problem that stable sealing performance cannot be secured.

In view of this, a gasket having the shape shown in FIG. 5 has been proposed to prevent the gasket from collapsing.
A main lip 700 having a triangular cross section is provided at the center of a flat gasket 600 having a horizontally long cross section, a sub lip 800 is provided on the opposite surface, and protrusions 900 and 900 for falling prevention are provided on the inner and outer peripheral ends thereof. It is an aspect.
However, although the fall prevention has a certain effect, the sealing performance is not sufficient, and it is difficult to keep the reaction force low enough.

Therefore, a fuel cell gasket having the shape shown in FIG. 6 has been proposed for the purpose of improving the sealing performance and keeping the reaction force low.
That is, it comprises an annular inner peripheral surface collar portion 300 and an annular seal portion 500 connected to the annular outer peripheral surface collar portion 400, and this seal portion 500 has a substantially triangular cross-sectional lip 106 protruding in both directions, A seal 111 made of 106 is provided.
The inner and outer peripheral surface collar portions 300 and 400 and the seal portion 500 are connected by the inner peripheral side joint portion 109 and the outer peripheral side joint portion 110 which are thinner than the thickness of the inner and outer peripheral surface collar portions 300 and 400.

This type of fuel cell gasket has a good sealing performance and can keep the reaction force low, but has caused a problem of falling.
That is, as shown in FIG. 7, when the separators 1 and 1 are mounted and compressed, they fall down, resulting in a problem that stable sealing performance cannot be secured.
JP 2001-108103 A JP 2006-4851 A

The present invention has been made in view of such a problem, and provides a fuel cell gasket that has a good sealing performance, can suppress a reaction force low, and solves a problem that the gasket falls. Objective.
Another object of the present invention is to provide a fuel cell gasket that is easy to manufacture and exhibits good sealing performance.

The gasket for a fuel cell according to the present invention is a gasket that is interposed between separators and seals, and is a fuel cell that includes an annular inner peripheral surface collar portion and an annular seal portion connected to the annular outer peripheral surface collar portion. In the gasket for use, the seal portion has an inner seal formed of a lip having a substantially triangular cross section projecting toward both surfaces of the separator, and a cross section substantially projecting toward both surfaces of the separator located outside the inner seal. A triangular lip and an outer seal, the two lips having the same cross-sectional shape, the inner seal and the outer seal being connected by an annular connecting portion, and the connecting portion being the inner The inner and outer joints are positioned at the center of the seal and the outer seal, and the inner and outer peripheral collars and the seal are thinner than the inner and outer peripheral collars. Characterized in that it is connected by a Into section.

The present invention has the following effects.
According to the gasket for a fuel cell of the invention described in claim 1, the gasket can be reliably prevented from falling down, the mounting stability is good, and an equal sealing performance can be exhibited for both sealed surfaces. Since the reaction force can be kept low, a stable sealing performance can be maintained for a long time.

Furthermore, according to the gasket for a fuel cell of the invention described in claim 2, it is possible to prevent a mounting error.
Furthermore, according to the gasket for a fuel cell of the invention described in claim 3, there is no damage to the mating surface, and the reaction force can be kept low.

Hereinafter, the best mode for carrying out the present invention will be described.
The best mode for carrying out the invention will be described with reference to FIGS.

In FIG. 1, it is a gasket which is interposed between separators and seals, and is composed of an annular inner peripheral surface flange portion 3 and an annular seal portion 5 connected to an annular outer peripheral surface flange portion 4. .
The seal portion 5 has an inner seal 11 formed of lips 6 and 6 having a substantially triangular cross section projecting in both directions (up and down in the drawing) and a substantially triangular cross section located outside the inner seal 11 and projecting in both directions. The outer seal 12 is composed of lips 7 and 7.

The inner seal 11 and the outer seal 12 are connected by an annular connecting portion 8. .
The connecting portion 8 is located in the center portion of the inner seal 11 and the outer seal 12, and the two lips 6 and 7 have the same cross-sectional shape.
The inner and outer peripheral surface collar portions 3 and 4 and the seal portion 5 are connected by an inner peripheral side joint portion 9 and an outer peripheral side joint portion 10 which are thinner than the thickness of the inner and outer peripheral surface collar portions 3 and 4.

For this reason, while the freedom degree of the seal part 5 increases, since the escape of the seal part 5 can be ensured, reaction force can be restrained low.
Further, since the apex angle α of the cross section of the lips 6 and 7 is 50 to 70 degrees, preferably 55 to 65 degrees, stable sealing performance can be maintained for a long period of time.
Furthermore, since the tops of the lips 6 and 7 have an arc shape, there is little risk of damage and stable sealing performance can be maintained.

As the material of the gasket for the fuel cell, a rubber-like elastic material such as silicone rubber, EPDM, or fluororubber is appropriately selected and used.
The lips 6 and 7 protrude from the surfaces of the inner and outer peripheral surface collar portions 3 and 4 by approximately half the thickness of the inner and outer peripheral surface collar portions 3 and 4.
As a result, an optimum seal surface pressure can be secured.

FIG. 2 shows a further best mode for carrying out the present invention.
1 is different from that of FIG. 1 in that the connecting portion 80 is made thicker.
Specifically, the connecting portion 8 has a thickness greater than the thickness of the inner and outer peripheral surface collar portions 3 and 4.
This makes it possible to more effectively prevent the collapse when the gasket is mounted.
FIG. 3 is a view showing a state in which the gasket shown in FIG. 2 is mounted between the separators 1 and 1.
As can be seen from the figure, the gasket is reliably prevented from falling down during mounting.

  The present invention is not limited to the best mode for carrying out the invention described above, and various other configurations can be adopted without departing from the gist of the present invention.

It is sectional drawing which shows embodiment of the invention concerning the gasket for fuel cells. It is sectional drawing which shows other embodiment of the invention concerning the gasket for fuel cells. It is sectional drawing which shows the mounting state of the gasket for fuel cells of FIG. It is sectional drawing which shows the prior art concerning the gasket for fuel cells. It is sectional drawing which shows the prior art concerning the gasket for fuel cells. It is sectional drawing which shows the prior art concerning the gasket for fuel cells. It is sectional drawing which shows the mounting state of the gasket for fuel cells of FIG.

Explanation of symbols

1 ... Separator 3 ... Inner peripheral side flange 4 ... Outer peripheral side flange 5 ... Seal part 6, 7 ... Lip 8 ... Connection part 9 ... Inner peripheral joint part 10 ... Outer peripheral side Joint part 11 ... inner seal 12 ... outer seal

Claims (3)

A gasket that is interposed between and sealed between separators (1) and (1), and is an annular seal portion (3) connected to an annular inner peripheral surface collar portion (3) and an annular outer peripheral surface collar portion (4). In the fuel cell gasket according to 5), the seal portion (5) includes lips (6) and (6) having a substantially triangular cross section projecting toward both surfaces of the separator (1) and (1). An inner seal (11) and a lip (7), (7) having a substantially triangular cross section located outside the inner seal (11) and projecting to both sides of the separator (1), (1) And the two lips (6) and (7) have the same cross-sectional shape, and the inner seal (11) and the outer seal (12) are annular connecting portions. (8) and the connecting portion (8) is connected to the inner seal (1). ) And the outer seal (12) at the center, and the inner and outer peripheral surface collar portions (3) and (4) and the seal portion (5) are connected to the inner and outer peripheral surface collar portions (3) and (4). A fuel cell gasket characterized in that the gasket is connected by an inner peripheral side joint portion (9) and an outer peripheral side joint portion (10) which are thinner than the wall thickness. 2. The fuel cell gasket according to claim 1, wherein the fuel cell gasket has a line-symmetric shape with respect to a line passing through a center of the inner and outer peripheral surface collar portions (3) and (4) in a gasket cross-sectional shape. . 3. The fuel cell gasket according to claim 1, wherein the fuel cell gasket is made of a rubber-like elastic material.

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