METHOD OF MANUFACTURING PLATE WITH FRAME

Abstract

A plate is provided in its outer edge portion with a concavo-concave shape which makes a frame hard to fall away. A metal mold is provided with a cavity portion and a gate portion. A plurality of gate portions are provided at positions facing to an outer edge thickness surface of a metal plate in a state of being set to the metal mold and are arranged at positions conforming to arrangement of concave portions in the concavo-convex shape. A plate with frame is manufactured by using the metal mold. The invention can provide a method manufacturing the plate with frame obtained by integrally molding a resin frame in an outer edge portion of the metal plate by using the metal mold, and an amount of deformation can be held down even if any deformation is generated in the plate edge portion when the frame is integrally molded in the plate.

Claims

1. A method of manufacturing a plate with frame by using a metal mold, the plate being obtained by integrally molding a resin frame in an outer edge portion of a metal plate, wherein said metal plate is provided with a concavo-convex shape for making said resin frame hard to fall away in the outer edge portion of the metal plate, wherein said metal mold is provided with a cavity portion for molding said resin frame in a state in which said metal plate is set to said metal mold, and a gate portion for injecting a frame molding material into said cavity portion, wherein said gate portion is constructed by a plurality of gate portions which are provided at positions facing to an outer edge thickness surface of said metal plate in a state of being set to said metal mold, and are arranged at positions conforming to arrangement of concave portions in said concavo-convex shape, and wherein the plate with frame is manufactured by using said metal mold.

2. A method of manufacturing a plate with frame by using a metal mold, the plate being obtained by integrally molding a resin frame in an outer edge portion of a metal plate, wherein said metal plate is provided with a concavo-convex shape for making said resin frame hard to fall away in the outer edge portion of the metal plate, wherein said metal mold is provided with a cavity portion for molding said resin frame in a state in which said metal plate is set to said metal mold, and a gate portion for injecting a frame molding material into said cavity portion, wherein said gate portion is constructed by a plurality of gate portions which are provided at positions facing to an outer edge thickness surface of said metal plate in a state of being set to said metal mold, weld portions which are positioned between a plurality of gate portions and where the flow of the frame molding materials meet are set in said resin frame formed by said cavity portion, wherein said metal mold is provided with a structure in which arrangement of said weld portions in the metal mold is conformed to arrangement of the concave portions in said concavo-convex shape in said metal plate in a state of being set to said metal mold, and wherein the plate with frame is manufactured by using said metal mold.

3. The method of manufacturing the plate with frame according to claim 1, wherein a circumferentially partly frame width enlargement portion is provided in said resin frame by enlarging the width of the resin frame molded by said metal mold in the portion including said weld portion in comparison with the other portions.

4. The method of manufacturing the plate with frame according to claim 2, wherein a circumferentially partly frame width enlargement portion is provided in said resin frame by enlarging the width of the resin frame molded by said metal mold in the portion including said weld portion in comparison with the other portions.

5. The method of manufacturing the plate with frame according to claim 1, wherein said metal plate is a metal separator for a fuel cell, and wherein said resin frame is a resin frame which is integrally molded in an outer edge portion of said metal separator.

6. The method of manufacturing the plate with frame according to claim 2, wherein said metal plate is a metal separator for a fuel cell, and wherein said resin frame is a resin frame which is integrally molded in an outer edge portion of said metal separator.

7. The method of manufacturing the plate with frame according to claim 3, wherein said metal plate is a metal separator for a fuel cell, and wherein said resin frame is a resin frame which is integrally molded in an outer edge portion of said metal separator.

8. The method of manufacturing the plate with frame according to claim 4, wherein said metal plate is a metal separator for a fuel cell, and wherein said resin frame is a resin frame which is integrally molded in an outer edge portion of said metal separator.

Description

BRIEF EXPLANATION OF THE DRAWINGS

[0019] FIG. 1 is a partly plan view of a gasket for a fuel cell (a plate integrated gasket) having a plate with frame which is manufactured by a manufacturing method according to an embodiment of the present invention;

[0020] FIGS. 2A and 2B are partly cross sectional views of the gasket, in which FIG. 2A is an enlarged cross sectional view along a line A-A in FIG. 1, and FIG. 2B is an enlarged cross sectional view along a line B-B in FIG. 1;

[0021] FIGS. 3A and 3B are partly cross sectional views of the plate with frame, in which FIG. 3A is an enlarged cross sectional view along the line A-A in FIG. 1, and FIG. 2B is an enlarged cross sectional view along the line B-B in FIG. 1;

[0022] FIG. 4 is an explanatory view of a manufacturing step of the plate with frame;

[0023] FIG. 5 is an explanatory view of a manufacturing step and shows the other example of the plate with frame;

[0024] FIG. 6 is a partly plan view showing the other example of the gasket for the fuel cell (the plate integrated gasket);

[0025] FIG. 7 is a partly cross sectional view of a gasket for a fuel cell (a plate integrated gasket) having a plate with frame which is manufactured by a manufacturing method according to a prior art; and

[0026] FIGS. 8A and 8B are views showing a metal plate according to a reference example, in which FIG. 8A is a partly plan view of the same, FIG. 8B is a partly cross sectional view, and FIG. 8C is a partly cross sectional view of a state in which a plate outer edge portion is deformed.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0027] The following embodiments are included in the present invention.

[0028] (1) The rubber burr is generated in the outer peripheral portion when rubber molding the separator integrated gasket obtained by vulcanizing the rubber in the metal separator, and a lot of man hour is required for the burr removing work. As a result, the generation of the rubber burr can be held down by molding the resin frame in the outer peripheral portion of the metal separator. On the other hand, there is a case that an insulation performance which is a function in a normal situation can not be secured due to the deformation of the metal separator itself when molding the outer peripheral resin frame.

[0029] (2) The outer peripheral resin frame is formed into a concavo-convex shape in a whole periphery of the metal separator outer peripheral portion for suppressing a falling out after the molding. However, since it is necessary to make the separator for the fuel cell thin, the thickness of the resin frame must be thinned. Therefore, it is necessary to arrange a plurality of cold gates over a whole periphery in the metal mold for securing a resin fluidity when molding the resin. Further, the deformation in the outer periphery of the metal separator is greatly affected by the resin flow since it is generated at the time of resin molding, and is frequently generated in the cold gate and the weld portion, and the deformation is under the influence of the flow at the time of resin molding.

[0030] (3) In the present invention, both or one of the cold gate and the weld portion is arranged in the concave portion in the outer periphery of the metal separator.

[0031] (4) It is assumed that the flow influence at the time of resin molding is greater than the other sections. The amount of deformation is smaller due to the influence of the dimensional shape in relation to the convex portion even in the case that the deformation is generated at the section, by arranging both or one of the cold gate and the weld portion, where deformation generation frequency is actually higher, in the concave portion in the outer periphery of the metal separator. As a result, it is possible to reduce the possibility that a fixed level or more deformation is generated as a whole.

Embodiments

[0032] Next, a description will be given to embodiments according to the present invention with reference to the accompanying drawings.

[0033] In a manufacturing method according to the embodiment, a plate 11 with frame shown in FIG. 3 is manufactured by using a metal mold 51 shown in FIG. 4 as a part of steps for manufacturing a gasket 1 for a fuel cell shown in FIGS. 1 and 2. The plate 11 with frame shown in FIG. 3 is obtained by integrally molding a resin frame 31 in an outer edge portion (a right end portion in the drawing) 22 of a metal separator 21 which corresponds to a metal plate. The gasket 1 for the fuel cell shown in FIGS. 1 and 2 is obtained by integrally molding a gasket (a gasket main body) 41 made of a rubber-like elastic material in both face sides in a thickness direction of the metal separator 21 and an inner side (an inner peripheral side, a left side in the drawing) of the resin frame 31 in an outer edge portion (a right end portion in the drawing) of the plate 11 with frame in FIG. 3. Therefore, first of all the plate 11 with frame shown in FIG. 3 is manufactured, and the gasket 11 for the fuel cell shown in FIGS. 1 and 2 is manufactured in the next step, according to this process order. A description will be given below to the method of manufacturing the plate 11 with frame shown in FIG. 3.

[0034] The metal separator 21 corresponding to the metal plate is provided with a predetermined planar shape, and is provided with a concavo-convex shape 23 which is formed by alternately arranging a lot of concave portions 24 and convex portions 25 in an outer edge portion 22 in its planar direction as shown in FIG. 1. Since the concavo-convex shape 23 is buried in the resin frame 31 as shown in FIG. 3, a contact area between the metal separator 21 and the resin frame 31 is set to be greater, thereby achieving a structure in which the resin frame 31 is hard to fall away from the outer edge portion 22 of the metal separator 21.

[0035] The plate 11 with frame is manufactured by a metal mold 51 which is schematically shown in FIG. 4. The metal mold 51 is provided in a parting surface 52 with a cavity portion 53 for molding the resin frame 31 in a state in which the metal separator 21 is set to the metal mold 51, and the cavity portion 53 is provided with a gate portion (a cold gate) 54 which is set for injecting a frame molding material into the cavity portion 53 and is connected from a runner portion 55.

[0036] The gate portion 54 is provided at a position facing to an outer edge thickness surface 22b of the metal separator 21. Therefore, a injecting pressure of molding material tends to act on the outer edge portion 22 of the metal separator 21, in the molding material injected into the cavity portion 53 from the gate portion 54.

[0037] Further, since the metal separator 21 is greater in its peripheral length than its thickness, a plurality of gate portions 54 are provided along a peripheral direction of the outer edge portion 22 of the metal separator 21. Reference numeral 32 in FIG. 1 indicates a gate trace which is left in the molded resin frame 31. As can be known from a plurality of (two in the drawing) gate traces 32 described here, a plurality of gate portions 54 are provided along the peripheral direction of the outer edge portion 22 of the metal separator 21.

[0038] In the case that a plurality of gate portions 54 are provided along the peripheral direction of the outer edge portion 22 of the metal separator 21 as mentioned above, a weld portion 33 is set in the resin frame 31 which is molded by the cavity portion 53, the weld portion 33 being generated by the combined flow of the frame molding material while being positioned between a plurality of gate portions 54 which are adjacent to each other. A pressure (a combined flow pressure caused by the combined flow of the frame molding materials is generated in the weld portion 33. Therefore, the combined flow pressure tends to act on the outer edge portion 22 of the metal separator 21.

[0039] In the metal mold 51 shown in FIG. 4, a plurality of gate portions 54 are respectively arranged at positions which conform to an arrangement of the concave portions 24 in the concavo-convex shape 23 in the outer edge portion 22 of the metal separator 21 in a state of being set to the metal mold 51. Here, the conforming means the circumferentially same position. In FIG. 1, the gate traces 32 are respectively provided at the positions conforming to the arrangement of the concave portions 24 in the concavo-convex shape 23 in the outer edge portion 22 of the metal separator 21, thereby showing the fact that a plurality of gate portions 54 are arranged at the positions conforming to the arrangement of the concave portions 24 in the concavo-convex shape 23 in the outer edge portion 22 of the metal separator 21 in the state of being set to the metal mold 51.

[0040] Further, gates intermediate positions are respectively arranged at positions conforming to the arrangement of the concave portions 24 in the concavo-convex shape 23 in the outer edge portion 22 of the metal separator 21 in the state of being set to the metal mold 51, the gates intermediate position being to generate the weld portion 33 in the resin frame 31, in the metal mold 51 shown in FIG. 4. In FIG. 1, the weld portion 33 is arranged at the position conforming to the arrangement of the concave portion 24 in the concavo-convex shape 23 in the outer edge portion 22 of the metal separator 21, thereby showing the fact that the gates intermediate positions are respectively arranged at the positions conforming to the arrangement of the concave portions 24 in the concavo-convex shape 23 in the outer edge portion 22 of the metal separator 21 in the state of being set to the metal mold 51.

[0041] The metal mold 51 is structured as mentioned above. Further, the plate 11 with frame shown in FIG. 3 is manufactured by using the metal mold 51.

[0042] As mentioned above, the gate portion 54 is provided at the position facing to the outer edge thickness surface 22b of the metal separator 21 and is arranged at the position conforming to the arrangement of the concave portion 24 in the concavo-convex shape 23 in the outer edge portion 22 of the metal separator 21, in the metal mold 51. Therefore, the metal separator 21 directly faces to the gate portion 54 in the portion having the concave portion 24 in the concavo-convex shape 23, and is deformed under the influence of the injecting pressure of the frame molding material which is injected from the gate portion 54. Since a portion having the concave portion 24 in the metal separator 21 is smaller in a protruding length protruding to an inner portion of the cavity in comparison with a portion having the convex portion 25 (L1<L2 on the assumption that L1 is a protruding length of the portion having the concave portion 24, and L2 is a protruding length of the portion having the convex portion 25), the portion having the concave portion 24 has a smaller amount of deformation even if being deformed under the influence of injecting pressure of a frame molding material. More specifically, even if the portion is bent at the same angle as that in FIG. 8C, a leading end of the outer edge portion does not reach a surface (an upper surface in the drawing) of the resin frame 31. The portion having the convex portion 25 and being adjacent to the portion having the concave portion 24 somewhat deforms in connection with the deformation of the portion having the concave portion 24, however, does not deform with a so great angle since it does not directly face to the gate portion 54. Therefore, the leading end of the outer edge portion does not reach the surface (the upper surface in the drawing) of the resin frame even in the portion having the convex portion 25. As a result, it is possible to prevent the matter that the outer edge portion 22 of the metal separator 21 is deformed greatly so as to make the leading end of the outer edge portion be exposed to the surface in relation to the resin frame 31, and the insulation performance is deteriorated, from being generated.

[0043] Further, the gates intermediate position generating the weld portion 33 in the resin frame 31 is arranged at the position conforming to the arrangement of the concave portion 24 in the concavo-convex shape 23 in the outer edge portion 22 of the metal separator 21, in the metal mold 51. Therefore, the metal separator 21 is deformed in the portion having the concave portion 24 in the concavo-convex shape 23 under the influence of the combined flow pressure. Here, since the portion having the concave portion 24 in the metal separator 21 is smaller in the protruding length protruding into the inner portion of the cavity in comparison with the portion having the convex portion 25 (L1<L2 on the assumption that L1 is the protruding length of the portion having the concave portion 24, and L2 is the protruding length of the portion having the convex portion 25), the portion having the concave portion 24 has a less amount of deformation even if it deforms under the influence of the combined flow pressure. More specifically, the leading end of the outer edge portion does not reach the surface (the upper surface in the drawing) of the resin frame 31 even if the portion having the concave portion 24 is bent at the same angle as that of FIG. 8C. The portion having the convex portion 25 and being adjacent to the portion having the concave portion 24 somewhat deforms in connection with the deformation of the portion having the concave portion 24, however, does not deform at a so great angle since the portion having the convex portion 25 is deviated from the gates intermediate position. Therefore, the leading end of the outer edge portion does not reach the surface (the upper surface in the drawing) of the resin frame 31 even in the portion having the convex portion 25. As a result, it is possible to prevent the matter that the outer edge portion 22 of the metal separator 21 greatly deforms, the leading end of the outer edge portion is exposed to the surface in relation to the resin frame 31 and the insulation performance is deteriorated, from being generated.

Other Embodiment

[0044] Further, the deformation of the outer edge portion 22 of the metal separator 21 in the weld portion 33, it is thought that a countermeasure to deformation suppression is implemented by enlarging the width of the resin frame 31 in the weld portion 33.

[0045] More specifically, the metal mold 51 is provided with a circumferentially partial cavity width enlargement portion 53A by enlarging a width w2 of the cavity portion 53 toward an outer peripheral side in relation to a width w1 in the other portions, at the gates intermediate position where the weld portion 33 is generated in the resin frame 31, as shown in FIG. 5.

[0046] Further, as shown in FIG. 6, the resin frame 31 molded by the metal mold 51 is provided with a circumferentially partly frame width enlargement portion (a swelling portion) 31A by enlarging a width of the resin frame 31 (a width of a portion including the weld portion 33) w2 toward an outer peripheral side in relation to a width w1 in the other portions, at the gates intermediate position where the weld portion 33 is generated.

[0047] Further, in the case that the frame width enlargement portion 31A is provided in the weld portion 33 of the resin frame 31 as mentioned above, it is possible to make a strength of the weld portion 33 where the strength is generally lowered in comparison with the other portions equal to the other portions, and it is possible to reduce a pressure difference between front and back sides of the weld portion 33. As a result, it is possible to suppress the deformation of the outer edge portion 22 of the metal separator 21 in the weld portion 33.

[0048] The planar shape of the frame width enlargement portion 31A is formed, for example, into a trapezoidal shape or an approximately trapezoidal shape which is inclined in both ends. The width w2 of the resin frame 31 including the frame width enlargement portion 31A has a relationship between 1.2 and 2 times the width w1 of the other portions, for example, a relationship of 1.5 times. A length of the frame width enlargement portion 31A is set to a length of one to two sets of combination of the concave portion 24 and the convex portion 25, for example, set to about 1.5 sets.

[0049] The entire disclosures of Japanese Patent Application No. 2015-142966 filed on Jul. 17, 2015 and Japanese Patent Application No. 2016-043271 filed on Mar. 7, 2016 are expressly incorporated by reference herein.