JP6151065B2 - Manufacturing method of plate-integrated gasket - Google Patents

Description

  The present invention relates to a method for manufacturing a plate-integrated gasket in which a gasket main body is integrally provided at a peripheral portion of a plate such as a separator constituting a fuel cell, for example.

  In a fuel cell, a gas diffusion layer is arranged on both sides in the thickness direction of a membrane electrode assembly (MEA) having a pair of electrode layers on both sides of an electrolyte membrane, and a separator is stacked on the fuel cell. Furthermore, it has a stack structure in which a large number of fuel cells are stacked. Then, the oxidizing gas (air) is supplied from the oxidizing gas flow path formed on one side of each separator to the cathode side of the membrane electrode assembly through one gas diffusion layer, and the fuel gas (hydrogen) is An electrochemical reaction that is the reverse reaction of the electrolysis of water supplied from the fuel gas flow path formed on the other surface of each separator to the anode side of the membrane electrode assembly through the other gas diffusion layer, that is, hydrogen Electricity is generated by a reaction that generates water from oxygen and oxygen.

  In this type of fuel cell, a plate-integrated gasket 100 for sealing fuel gas, oxidizing gas, water generated by the above-described electrochemical reaction, surplus air, and the like is used for each fuel cell. As shown in FIGS. 9 and 10, this plate-integrated gasket 100 is a gasket main body made of a rubber-like elastic material (rubber material or synthetic resin material having rubber-like elasticity) at the periphery of a plate 101 such as a metal separator. The seal lip 102a is formed in a mountain shape on both sides in the thickness direction.

  However, when the plate 101 is a metal separator or the like, the plate 101 is thin and flexible. Therefore, when the gasket body 102 is integrally formed on the peripheral edge portion 101a, as shown in FIG. The peripheral edge portion 101a may be bent and deformed in the gasket main body 102 due to inflow pressure or the like. In the worst case, a part of the deformed plate 101 is exposed from the gasket main body 102. There was a possibility that the sealing performance of the glass was impaired.

  Therefore, as a method for preventing such deformation of the plate 101 due to injection pressure or the like, first, as shown in FIG. As shown in FIG. 13, it is effective to injection-mold the gasket body 102B on the other side.

  However, this method not only increases the cost because the molding is performed twice, but the plate 101 on which the gasket main body 102A on one side is molded needs to be set in another mold. As shown in FIG. 13, the dimensional accuracy deteriorates due to backlash at the time of positioning, resulting in misalignment δ between the gasket main bodies 102A and 102B on both sides, and further along the parting surface of the mold, as shown in FIG. As described above, there is a possibility that a thin burr 103 may be generated.

  Further, by sandwiching the peripheral portion 101a of the plate 101 set in the mold with a pressing protrusion provided on the mold, the gasket main bodies 102A and 102B on both sides are simultaneously formed while preventing the peripheral portion 101a of the plate 101 from being deformed. It is also possible (see Patent Document 1).

  However, as shown in FIG. 15, the plate-integrated gasket 100 molded by such a method exposes a part of the plate 101 in the hole-shaped molding mark 104 formed by the pressing protrusions. Cannot be used in applications that require the use of the material, and there is a risk that the exposed portion may corrode, and the mold structure becomes complicated and the mold cost becomes high.

  Therefore, it is conceivable that a molded product for holding the plate is preliminarily integrally formed on the entire periphery of the plate 101 with rubber or synthetic resin (see Patent Document 2 for a similar technique, although the purpose is different). It is not possible to provide a gate or vent when molding the gasket body on the inner periphery of the molded product, and a mold for molding the molded product for holding the plate is required for each product specification, so that productivity There is a problem with production costs.

Japanese Patent No. 4394935 Japanese Patent No. 4482414

  The present invention has been made in view of the above points, and its technical problem is that the molding pressure of the rubber material for molding when the gasket body is integrally molded on both sides of the peripheral edge of the flexible plate. An object of the present invention is to provide a method for manufacturing a plate-integrated gasket that can effectively prevent deformation of the plate due to the above.

As a means for effectively solving the technical problem described above, the method for manufacturing a plate-integrated gasket according to the invention of claim 1 is characterized in that a plurality of holders that cover the peripheral portion of the plate from both sides in the thickness direction are arbitrarily provided at the peripheral portion. Mounting the plate in the mold together with the holder, supporting the plate in the gasket molding cavity via the holder, and molding rubber in the gasket molding cavity. And filling a material to form a gasket main body integral with the plate and the holder.

  The manufacturing method of the plate-integrated gasket according to the invention of claim 2 is the manufacturing method according to claim 1, wherein the holder has no rubber-like elastic material (rubber material or synthetic resin material having rubber-like elasticity) or rubber-like elasticity. It is made of a synthetic resin material and has electrical insulation.

  The manufacturing method of the plate-integrated gasket according to the invention of claim 3 is the manufacturing method according to claim 1 or 2, wherein locking means capable of locking each other is formed on the peripheral portion of the plate and the holder. .

  According to the method for manufacturing a plate-integrated gasket according to the present invention, since the peripheral portion of the plate is supported in the gasket forming cavity by the holder, bending deformation of the peripheral portion of the plate due to the injection pressure of the rubber material for molding is prevented. For this reason, the gasket bodies on both sides can be molded at the same time, and the holder can be attached to the peripheral edge of the plate at an arbitrary interval, so that it can be used for general purposes, and therefore can be manufactured at low cost. Can do.

  Also, if the holder is made of rubber or synthetic resin, it has good bondability with the gasket body, and if locking means capable of locking each other is formed on the peripheral edge of the plate and the holder, the peripheral edge of the plate It is possible to prevent the holder once attached from falling off easily during setting to the mold, or to prevent the peripheral edge of the plate from easily coming off due to the inflow pressure of the molding rubber material in the gasket molding cavity. .

It is a top view which shows an example of the plate integrated gasket manufactured by the manufacturing method of the plate integrated gasket which concerns on this invention. It is A-A 'sectional drawing in FIG. It is an A-A 'cross-section perspective view in FIG. In embodiment of the manufacturing method of the plate integrated gasket which concerns on this invention, it is sectional drawing which shows the state which attached the holder to the peripheral part of the plate. In embodiment of the manufacturing method of the plate integrated gasket which concerns on this invention, it is a cross-sectional perspective view which shows the state which attached the holder to the peripheral part of the plate. In embodiment of the manufacturing method of the plate integrated gasket which concerns on this invention, it is sectional drawing which shows the state which set the plate which attached the holder in the metal mold | die. It is a fragmentary top view which shows other embodiment in the manufacturing method of the plate integral gasket which concerns on this invention. It is a fragmentary top view which shows other embodiment in the manufacturing method of the plate integral gasket which concerns on this invention. It is a top view which shows an example of the plate integrated gasket manufactured by the conventional manufacturing method. FIG. 10 is a cross-sectional view taken along line A-A ′ in FIG. 9. It is sectional drawing which shows the example which produced the deformation | transformation in the peripheral part of the plate within the gasket main body. It is sectional drawing which shows the state which shape | molded the gasket main body to the one side of the peripheral part of a plate in the conventional manufacturing method which molds a gasket main body in 2 steps. In the conventional manufacturing method which molds a gasket main body in two steps, it is sectional drawing which shows the state which shape | molded the gasket main body also on the other side of the peripheral part of a plate. In the conventional manufacturing method which molds a gasket main body in two steps, it is sectional drawing which shows the state which produced the positional offset mutually on the gasket main body of both sides. It is sectional drawing which shows the state which produced the thin burr | flash in the conventional manufacturing method which molds a gasket main body in 2 steps.

  Hereinafter, a preferred embodiment of a method for producing a plate-integrated gasket according to the present invention will be described with reference to the drawings.

  1 to 3 show an example of a plate-integrated gasket manufactured by a method for manufacturing a plate-integrated gasket according to the present invention. Reference numeral 1 denotes a flexible plate such as a metal separator constituting a fuel cell. Reference numeral 2 is a gasket body integrally formed on the outer peripheral edge of the plate 1 and the inner peripheral edge of the opening 1a of the plate 1, and reference numeral 3 is attached to the peripheral edge of the plate 1 and integrated with the gasket main body 2. It is a holder.

  The gasket body 2 is formed of a rubber-like elastic material (rubber material or a synthetic resin material having rubber-like elasticity), and as shown in FIGS. It consists of a plate-like base portion 21 joined so as to surround the portion in a U-shaped cross section, and seal lips 22 and 22 protruding in a mountain shape from both sides in the thickness direction.

  The holder 3 is an electrically insulating material made of a rubber-like elastic material or a synthetic resin material having no rubber-like elasticity, and is formed into a bar shape having a U-shaped cross section. As shown in FIGS. A plurality of grooves 31 at the middle in the vertical direction are fitted into the peripheral edge of the plate 1, so that a plurality of grooves 31 are attached to the peripheral edge at arbitrary intervals so as to cover from both sides in the thickness direction. On the outer peripheral side, it is integrated with the base 21 so as to form a part of the base 21 of the gasket body 2. The groove 31 has a slight margin for the peripheral edge of the plate 1.

  The plate-integrated gasket having the above configuration is used, for example, as a laminated part constituting a fuel cell, and the seal lips 22 and 22 in the gasket body 2 are brought into close contact with other laminated parts in an appropriately compressed state. It has a sealing function for fuel gas and oxidizing gas supplied to the fuel battery cell, water generated by electrochemical reaction, excess air, or the like.

  In the manufacture of the plate-integrated gasket, as shown in FIGS. 4 and 5, first, a plurality of holders 3 and grooves 31 formed in the holder 3 are fitted into the peripheral edge of the plate 1. Install at appropriate intervals.

  Next, the plate 1 to which the holder 3 is attached is set in a gasket molding die 4 as shown in FIG. The mold 4 has divided dies 41 and 42 that are abutted and separated from each other, and clamping surfaces 41a and 42a that can clamp the plate 1 by clamping are formed between the opposing surfaces thereof, and the outside thereof. Further, a gasket molding cavity 43 is defined between the outer peripheral edge of the plate 1 and the holder 3, and sandwiching surfaces 41b and 42b capable of clamping the holder 3 by clamping are formed on the outer side thereof, and further on the outer side thereof. Further, mutual abutting surfaces 41c and 42c are formed.

  The gasket molding cavity 43 has a shape corresponding to that of the gasket body 2 shown in FIGS. 2 and 3, and in FIG. 6, it is separated into spaces 43 a and 43 b on both sides in the thickness direction of the plate 1 by the holder 3. As can be seen, the spaces 43a and 43b on both sides in the thickness direction of the plate 1 are continuous gasket-forming cavities 43 through a portion where the holder 3 is not attached.

  Then, when the plate 1 to which the holder 3 is attached is set in the mold 4, the split molds 41 and 42 are clamped, so that the plate 1 is separated from the split molds 41 and 42 on the inner peripheral side of the gasket forming cavity 43. The holder 3 which is sandwiched between the sandwiching surfaces 41a and 42a and attached to the peripheral edge of the plate 1 located in the gasket molding cavity 43 is sandwiched between the sandwiching surfaces 41b and 42b of the split dies 41 and 42, in other words. For example, the peripheral edge of the plate 1 is supported in the gasket forming cavity 43 via the holder 3, and the split dies 41 and 42 are brought into close contact with each other at the abutting surfaces 41c and 42c.

  Next, an unvulcanized molding rubber material made of liquid rubber is injected and filled into the gasket molding cavity 43 through a runner and a gate (not shown) opened in the split mold 41. The liquid rubber flowing from the gate into the space 43a on one side of the plate 1 in the gasket forming cavity 43 goes around the peripheral edge of the plate 1 at a portion between the holders 3, 3,. The space 43b on the other side is also filled. At this time, the bending deformation force acts on the peripheral portion of the plate 1 due to the injection pressure of the liquid rubber, etc., but the peripheral portion of the plate 1 is supported by holders 3, 3,. Therefore, bending deformation is effectively prevented. Then, the liquid rubber is crosslinked and cured in the gasket forming cavity 43, whereby the gasket body 2 integrated with the plate 1 and the holder 3 is formed as shown in FIGS.

  In the plate-integrated gasket manufactured in this manner, the peripheral edge of the plate 1 in the gasket body 2 is held in a flat shape, so that good sealing performance of the gasket body 2 is ensured.

  In addition, when a continuous holder is provided on the peripheral edge of the plate 1, it is necessary to newly manufacture a mold for forming the holder for each shape and size of the plate 1 (gasket body 2). Since the holder 3 is attached to the peripheral portion of the plate 1 at an arbitrary interval, it is versatile and can be shared even if the shape and size of the plate 1 (gasket body 2) are changed.

  Furthermore, the gasket main body 2 made of a rubber-like elastic material naturally has electrical insulation, but the holder 3 is also made of an electrical insulation material, so that electrical insulation can be ensured. it can.

  As a method of improving the supporting force of the peripheral portion of the plate 1 by the holder 3 and more reliably preventing the bending deformation of the peripheral portion of the plate 1 due to the injection pressure of the liquid rubber, as shown in FIG. It is effective to form locking means that can be locked to each other at the peripheral edge of the plate 1 and the holder 3.

Among these, FIG. 7 shows that as the locking means that can be locked to each other, a large number of dovetail irregularities 11 and 12 are formed on the peripheral edge of the plate 1, and the inner surface of the groove 31 of the holder 3 A plurality of irregularities 32 and 33 having a shape corresponding to the irregularities 11 and 12 on the peripheral edge are formed. That plate width w ₁₁ of the front end of one side of the protrusion 11 is slightly larger than the width w ₃₂ of the entrance of the recess 32 of the holder 3 side, in other words, the width of the tip of the holder 3 side of the convex portion 33 is plate 1 side It is slightly larger than the width of the entrance of the recess 12 of the above.

  That is, according to the embodiment shown in FIG. 7, when the groove 31 of the holder 3 is fitted into the peripheral edge of the plate 1, the groove 31 of the holder 3 is opened and the inner surface of the groove 31 is The formed irregularities 32 and 33 can be fitted to the irregularities 11 and 12 formed on the peripheral edge of the plate 1 in a dovetail shape. For this reason, when the plate 1 to which the holder 3 is attached is set in the mold 4 and liquid rubber is injected and filled into the gasket forming cavity 43, the peripheral portion of the plate 1 is held by the holder 3 by the pressure of the liquid rubber. The groove 31 is not easily detached from the groove 31 and is reliably supported.

  Further, FIG. 8 shows that the engaging holes 13 are formed at predetermined intervals along the peripheral edge of the plate 1 as locking means that can be locked to each other, and the inner surface of the groove 31 of the holder 3 is formed on the inner surface of the plate 1. A plurality of fitting protrusions 34 corresponding to the fitting holes 13 are formed.

  That is, according to the embodiment shown in FIG. 8, when the groove 31 of the holder 3 is fitted into the peripheral edge of the plate 1, the groove 31 of the holder 3 is opened and the inner surface of the groove 31 is The formed fitting protrusion 34 can be engaged with the fitting hole 13 formed along the peripheral edge of the plate 1. Therefore, also in this case, when the plate 1 to which the holder 3 is attached is set in the mold 4 and liquid rubber is injected and filled into the gasket forming cavity 43, the peripheral portion of the plate 1 is caused by the pressure of the liquid rubber. The holder 3 does not easily fall out of the groove 31 and is reliably supported.

1 Plate 11, 12 Concavity and convexity (locking means)
13 Fitting hole (locking means)
2 Gasket body 21 Base 22 Seal lip 3 Holder 31 Groove 32, 33 Concavity and convexity (locking means)
34 Fitting protrusion (locking means)
4 Mold 43 Gasket molding cavity

Claims (3)

A step of attaching a plurality of holders covering the peripheral edge of the plate from both sides in the thickness direction to the peripheral edge at an arbitrary interval, and setting the plate together with the holder in a mold so that the plate is gasketed via the holder. A plate-integrated gasket comprising: a step of supporting in a molding cavity; and a step of filling the gasket molding cavity with a molding rubber material and molding a gasket main body integral with the plate and the holder. Manufacturing method.   2. The method for producing a plate-integrated gasket according to claim 1, wherein the holder is made of a rubber-like elastic material or a synthetic resin material having no rubber-like elasticity and has an electrical insulation property.   3. The method for manufacturing a plate-integrated gasket according to claim 1, wherein locking means capable of locking each other are formed on the peripheral portion of the plate and the holder.

Images