JP2002033109A - Fuel cell separator adhering seal structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel cell separator adhering seal structure capable of integrating a seal rubber piece 4 with a carbon separator 1 without causing a crack in the carbon separator 1 having relatively low strength. SOLUTION: The seal rubber piece 4 previously formed as a separate body is bonded to a groove part 2 formed in a seal needing part of the carbon separator 1 in a post-assembly process.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel cell separator adhesive seal structure having a fuel cell separator as a part of its constituent elements.

[0002]

2. Description of the Related Art As shown in FIG. 4, conventionally, gaskets 54 are respectively arranged between an ion exchange membrane 52 in a reaction electrode portion 51 of a fuel cell and a pair of separators (also called collector electrodes) 53 sandwiching the same. The ion exchange membrane 52, the gasket 54 and the separator 53 are separate components. Therefore, this prior art has the disadvantage that a great deal of man-hours are required to assemble the parts together to assemble the fuel cell or stack.

In order to solve the above-mentioned inconvenience, a technique has been developed in which the seal rubber serving as the gasket 54 is integrated with the separator 53 in advance. According to this technique, the gasket 54 and the separator 53 are integrated in advance. In addition, the assembling work of the fuel cell unit or the stack can be facilitated. In the integration of the gasket 54 and the separator 53, the separator 53 is inserted into the cavity of the mold for molding the seal rubber to mold the seal rubber, and the seal rubber is integrated with the separator 53 simultaneously with the molding of the seal rubber.

However, according to the prior art, when the separator 53 is made of carbon which is relatively weak in strength, the separator 53 inserted into the mold receives a mold clamping pressure, a molding pressure, etc. 53 may be cracked.

[0005]

DISCLOSURE OF THE INVENTION In view of the above, the present invention provides a fuel capable of integrating a sealing rubber with a carbon separator having relatively low strength without causing cracks in the carbon separator. An object of the present invention is to provide a battery separator adhesive seal structure.

[0006]

In order to achieve the above-mentioned object, a fuel cell separator adhesive seal structure according to claim 1 of the present invention is provided with a seal rubber formed separately in advance at a place where a seal is required of a carbon separator. The present invention is characterized in that it is adhered to the groove later.

Further, the fuel cell separator adhesive seal structure according to claim 2 of the present invention comprises a carbon separator having a groove at a position where a seal is required, an adhesive applied in the groove, and the adhesive. And a sealing rubber bonded to the separator.

[0008] In the sealing structure according to the first aspect of the present invention having the above-described structure, the sealing rubber formed in advance as a separate body is attached later to the groove provided at the sealing required portion of the carbon separator. There is no need to insert the carbon separator into the mold for molding the seal rubber as in the prior art, so that no mold clamping pressure or molding pressure acts on the carbon separator.

[0009] Further, since the adhesion position of the seal rubber to the separator is specified in a groove provided in advance in the separator, it is possible to accurately position the seal rubber with respect to the separator.

[0010] In addition, in the seal structure according to the second aspect of the present invention having the above structure, since the adhesive is applied in the groove provided in the separator in advance, the adhesive is removed from the outside of the groove. It is possible to prevent exudation.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view of a main part of a fuel cell separator adhesive seal structure according to an embodiment of the present invention, and FIG. 2 shows a state before the adhesion. This seal structure is configured as follows.

First, a carbon separator 1 which is a part of a fuel cell unit is provided, and a carbon separator 1 is provided on one surface of the carbon separator 1 which is required to be sealed, along the required sealing portion. The groove 2 having a flatness greater than the flatness of the groove 1 is provided.
The flatness of the carbon separator 1 is about 0.1 mm in actual size.
, And the other hand, the width _{w 1} of the groove 2 is 3m to scale
m and depth d are about 0.25 mm in actual size.

An adhesive 3 is applied to the inside of the groove 2 using an instrument such as a dispenser.
Thereby, the seal rubber 4 serving as a gasket is adhered to the carbon separator 1.

The seal rubber 4 has a lip portion 4 having a triangular cross section on the upper surface of a flat base portion 4a disposed in the groove portion 2.
b is integrally formed, and is entirely bonded to the bottom surface of the groove 2 with the lower surface of the base 4a. Whereas the width w ₁ of the groove portion 2 as described above is about 3 mm, the width w ₂ of the width of the base portion 4a i.e. sealing rubber 4 is formed of about 2.5mm in actual size.

The seal rubber 4 is separately and separately molded in advance using silicone rubber, EPDM rubber, FKM rubber, or the like as a molding material, and is later attached to the carbon separator 1 by the adhesive 3.

In the sealing structure having the above-described structure, the sealing rubber 4 separately and separately molded in advance is adhered to the carbon separator 1 by the adhesive 3 afterwards. Does not need to be inserted into the mold for molding the seal rubber. Accordingly, since the mold clamping pressure, the molding pressure, and the like do not act on the carbon separator 1, the occurrence of cracks in the carbon separator 1 can be prevented.

In addition, in the sealing structure having the above-mentioned structure, the bonding portion of the sealing rubber 4 to the carbon separator 1 is formed by a groove 2 provided in the carbon separator 1 in advance.
Therefore, the sealing rubber 4 can be bonded to the carbon separator 1 with high positioning accuracy. Therefore, it is possible to provide a separator product in which the positioning accuracy of the seal rubber 4 with respect to the carbon separator 1 is high.

Further, since the adhesive 3 is applied to the groove 2 provided in the carbon separator 1 in advance, it is possible to prevent the adhesive 3 from leaking out of the groove 2. Therefore, it is possible to prevent the adhesive 3 protruding from the groove 2 from reaching the power generation portion of the carbon separator 1 and causing an electrical failure such as a power generation failure.

The bonding step is preferably performed using a bonding jig 11 as shown in FIG. 3 so that the carbon separator 1 does not crack.

That is, the bonding jig 11 presses the seal rubber 4 against the carbon separator 1 by a combination of an upper jig 12 and a lower jig 13 which are fitted to each other.
In this pressed state, the adhesive 3 is solidified to integrate the seal rubber 4 with the carbon separator 1.
As a third component, a cushion rubber 14 of low hardness (about Hs20) is arranged on the lower surface side of the carbon separator 1. Therefore, according to the bonding jig 11, it is possible to prevent the stress concentration of the carbon separator 1 from occurring due to the cushioning action of the cushion rubber 14, thereby effectively preventing the carbon separator 1 from cracking. Can be prevented.

[0022]

The present invention has the following effects.

First, in the sealing structure according to the first aspect of the present invention having the above-described structure, the sealing rubber formed separately in advance is bonded later to the groove portion provided at the sealing required portion of the carbon separator. In addition, unlike the prior art, there is no need to insert the carbon separator into the mold for molding the seal rubber. Therefore, since the mold clamping pressure and the molding pressure do not act on the carbon separator, it is possible to prevent the carbon separator from being cracked.

[0024] Further, since the bonding portion of the seal rubber to the separator is specified in a groove provided in advance in the separator, the sealing rubber can be bonded to the separator with high positioning accuracy. Therefore, it is possible to provide a separator product having high positioning accuracy of the seal rubber with respect to the separator.

In addition, in the sealing structure according to the second aspect of the present invention having the above structure, since the adhesive is applied to the groove provided in the separator in advance, the adhesive is applied to the outside of the groove. It is possible to prevent exudation. Therefore, it is possible to prevent the adhesive material that has protruded from the groove portion from reaching the power generation portion of the separator and causing electrical trouble such as power generation failure.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a main part of a fuel cell separator adhesive seal structure according to an embodiment of the present invention.

FIG. 2 is a sectional view of a main part showing a state before bonding of the separator bonding seal structure.

FIG. 3 is a cross-sectional view of a main part showing a bonding process of the separator bonding seal structure.

FIG. 4 is an explanatory view according to a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Separator 2 Groove 3 Adhesive material 4 Seal rubber 4a Base 4b Lip part 11 Adhesive jig 12 Upper jig 13 Lower jig 14 Cushion rubber 51 Reaction electrode part 52 Ion exchange membrane 53 Separator (collector electrode) 54 Gasket

Claims (2)

[Claims] An adhesive seal structure for a fuel cell separator, characterized in that a seal rubber (4) formed in advance as a separate body is attached later to a groove (2) provided in a portion of the carbon separator (1) where sealing is required. 2. A separator (1) made of carbon having a groove (2) provided at a position requiring a seal, an adhesive (3) applied in the groove (2), and the separator (3) formed by the adhesive (3). A fuel cell separator adhesive seal structure comprising: a seal rubber (4) adhered to (1).