Method of producing fiber-reinforced resin-molded member, and method of connecting members

Abstract

A method of producing a fiber-reinforced resin-molded member includes: preparing a mold including an upper mold and a lower mold forming a cavity, a cavity surface of either the upper mold or the lower mold being provided with a projecting portion; disposing a fiber-reinforcing material in the cavity, closing the molds to generate a state in which the projecting portion presses a part of the fiber-reinforcing material, and filling the cavity with a melted resin to impregnate the fiber-reinforcing material with the melted resin and cure the melted resin; and opening the molds to obtain a fiber-reinforced resin-molded member having an exposed portion and an embedded portion. The exposed portion includes at least a portion pressed by the projecting portion while the molds are closed.

Claims

1. A method of producing a fiber-reinforced resin-molded member, the method comprising: providing a mold including an upper mold and a lower mold by both of which a cavity is formed, a cavity surface of the upper mold or a cavity surface of the lower mold facing the cavity and being provided with a projecting portion; disposing a fiber-reinforcing material in the cavity; closing the upper mold and the lower mold to generate a state in which the projecting portion directly presses a portion of the fiber-reinforcing material, in turn compressively deforming each of the directly pressed portion and peripheral fiber-reinforcing material portions of the directly pressed portion; filling the cavity with a melted resin to impregnate the fiber-reinforcing material with the melted resin, the impregnated resin hardly permeating each of the deformed portion of the fiber-reinforcing material directly pressed by the projecting portion and the deformed peripheral portions of the directly pressed portion; curing the impregnated resin to form the fiber-reinforced resin-molded member; and opening the upper mold and the lower mold to obtain the fiber-reinforced resin-molded member, the fiber-reinforced resin-molded member having an exposed portion where the fiber-reinforcing material is exposed to an outside of the cured resin and a portion where the fiber-reinforcing material is embedded in the cured resin, and the exposed portion including at least the directly pressed portion.

2. The method of producing a fiber-reinforced resin-molded member according to claim 1, wherein the projecting portion includes a core disposed on the cavity surface.

3. A method of connecting members, the method comprising: producing a first fiber-reinforced resin-molded member and a second fiber-reinforced resin-molded member each by the method according to claim 1; disposing the exposed portion of the first fiber-reinforced resin-molded member opposite to the exposed portion of the second fiber-reinforced resin-molded member; and connecting the first fiber-reinforced resin-molded member and the second fiber-reinforced resin-molded member to each other by curing a melted resin at least between the oppositely disposed exposed portions of the first and second fiber-reinforced resin-molded members.

4. A method of connecting members, the method comprising: producing a fiber-reinforced resin-molded member by the method according to claim 1; disposing the exposed portion of the fiber-reinforced resin-molded member to be opposite to a predetermined resin-molded member; heating and melting a resin of the predetermined resin-molded member in a portion of the predetermined resin-molded member opposite to the exposed portion; impregnating the exposed portion with the melted resin of the opposite portion of the predetermined resin-molded member; and curing the resin of the opposite portion which has impregnated the exposed portion so as to connect the fiber-reinforced resin-molded member and the predetermined resin-molded member to each other.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Features, advantages, and technical and industrial significance of exemplary embodiments of the invention will be described below with reference to the accompanying drawings, in which like numerals denote like elements, and wherein:

(2) FIG. 1 is a drawing showing a first step and a part of a second step of a method of producing a fiber-reinforced resin-molded member of a first embodiment of the present invention;

(3) FIG. 2 is a view taken in line II-II of FIG. 1;

(4) FIG. 3 is a drawing showing a part of the second step continued from FIG. 1;

(5) FIG. 4 is a drawing showing a part of a third step and a produced fiber-reinforced resin-molded member;

(6) FIG. 5A and FIG. 5B are drawings showing a method of connecting members of a second embodiment of the present invention; and the method of connecting the members of the second embodiment of the present invention is carried out in the order of FIG. 5A and FIG. 5B; and

(7) FIG. 6A and FIG. 6B are drawings showing a method of connecting members of a third embodiment of the present invention; and the method of connecting the members of the third embodiment of the present invention is carried out in the order of FIG. 6A and FIG. 6B.

DETAILED DESCRIPTION OF EMBODIMENTS

(8) A method of producing a fiber-reinforced resin-molded member of a first embodiment of the present invention and a method of connecting members will be described with reference to drawings hereinafter. A fiber-reinforced resin-molded member or a resin-molded member, i.e. a different member, exemplified in the drawings has a planar shape, and thus a connected portion thereof also has a planar shape, but these members and the connected portion may have a three-dimensional shape, such as a curved shape and a wavy shape. In the illustrated examples, a projecting portion is formed with a core disposed on a cavity surface of an upper mold, but the projecting portion may be integrated with a cavity surface of the upper mold or a lower mold. The number of the projecting portions, and the position and the planar shape of the projecting portion are not limited to the illustrated examples.

(9) FIG. 1 is a drawing showing a first step and a second step of the method of producing the fiber-reinforced resin-molded member of the first embodiment of the present invention. FIG. 3 is a drawing showing the second step continued from FIG. 1. FIG. 4 is a drawing showing a third step as well as a produced fiber-reinforced resin-molded member.

(10) As shown in FIG. 1, there is prepared a mold 10 that includes: an upper mold 1 and a lower mold 2 by both of which a cavity 3 is formed (first step).

(11) The mold 10 is opened, a fiber-reinforcing material 20 is disposed in the cavity 3, a projecting portion 4 formed of a core in a block shape is placed at a desired position of the fiber-reinforcing material 20, and the mold 10 is then closed.

(12) The projecting portion 4 may be bonded at a predetermined position of the cavity surface of the upper mold 1. The illustrated example shows a case in which a single projecting portion 4 is used, but a plurality of projecting portions 4 may be used at plural predetermined positions. The illustrated projecting portion 4 has a rectangular planer shape, but any shape, such as a square and a circle, may be selected, and the plane area of the projecting portion 4 may be set depending on the number of the projecting portions 4 and connecting strength required for a connected portion between the two members.

(13) The fiber-reinforcing material 20 to be disposed in the cavity 3 may be any of a continuous-fiber-reinforcing material, a long-fiber-reinforcing material, and a short fiber-reinforcing material, and it may be preferable to employ a continuous-fiber-reinforcing material having a fiber length of 50 mm or more, or a long-fiber-reinforcing material having a fiber length of less than 50 mm, for example, more than 10 mm to approximately 30 mm or less so as to produce a high-strength member.

(14) As shown in FIG. 2, the fiber-reinforcing material 20 is formed by collecting continuous reinforcing fibers and others into a shape and a dimension approximate to a shape and a dimension of the cavity 3, and an example of a raw material of the fiber-reinforcing material 20 may include any one of, or a mixture of two or more of ceramic fibers made of boron, alumina, silicon carbide, silicon nitride, zirconia, or the like; inorganic fibers such as glass fibers and carbon fibers; metallic fibers made of copper, steel, aluminum, stainless steel, or the like; and organic fibers made of polyamide, polyester, or the like.

(15) The fiber-reinforcing material 20 is disposed in the cavity 3 of the mold 10, and the upper mold 1 and the lower mold 2 are closed, thereby generating a state in which the projecting portion 4 presses a predetermined portion of the fiber-reinforcing material 20, as shown in FIG. 1 and FIG. 2.

(16) As shown in FIG. 2, when the predetermined portion of the fiber-reinforcing material 20 is downwardly pressed by the projecting portion 4 with a pressing force P, not only the portion directly pressed by the projecting portion 4 but also a peripheral region thereof are deformed downward.

(17) While the predetermined portion of the fiber-reinforcing material 20 is maintained to be pressed by the projecting portion 4 in the cavity 3, the cavity 3 is filled with a melted resin 30, as shown in FIG. 3.

(18) As a raw material of the melted resin 30, any of a thermoplastic resin and a thermosetting resin may be used; and as the thermoplastic resin, it is possible to employ any one of, or a material including a mixture of two or more of a crystalline plastic such as polyethylene (PE), polypropylene (PP), polyamide (PA: nylon 6, nylon 66, etc.), polyacetal (POM), and polyethylene terephthalate (PET); and an amorphous plastic such as polystyrene (PS), polyvinyl chloride (PVC), polymethylmethacrylate (PMMA), ABS resin, and thermoplastic epoxy resin. An example of the thermosetting resin may include an epoxy resin, a phenol resin, and an unsaturated polyester-based resin or the like.

(19) The melted resin 30 supplied in the cavity 3 permeates the fiber-reinforcing material 20 to spread across the entire cavity 3, but hardly permeates a portion of the fiber-reinforcing material 20 directly pressed by the projecting portion 4 and peripheral portions thereof (portions that are not directly pressed but deformed due to influence from the directly pressed portion).

(20) The melted resin 30 supplied in the cavity 3 is cured (the above is the second step), and subsequently, the mold 10 is opened for the mold releasing so as to produce a fiber-reinforced resin-molded member 40 (third step) as shown in FIG. 4. As shown in FIG. 4, in the produced fiber-reinforced resin-molded member 40, the fiber-reinforcing material 20 is basically embedded in the cured resin, but the portion pressed by the projecting portion 4 is compressively deformed; thus an exposed portion 40a that the melted resin does not permeate is formed, and the inner fiber-reinforcing material 20 is exposed to the outside in the exposed portion 40a.

(21) As described above, in the illustrated method of producing the fiber-reinforced resin-molded member, the method is applied including impregnating the fiber-reinforcing material 20 with the melted resin 30 while pressing the desired position of the fiber-reinforcing material 20 by the projecting portion 4 formed of the core and others so as to produce the fiber-reinforced resin-molded member 40. Thus, it is possible to produce the fiber-reinforced resin-molded member 40 while forming the exposed portion 40a in which the inner fiber-reinforcing material 20 is exposed to the outside at the desired position of the fiber-reinforced resin-molded member 40 with high accuracy by a simple method.

(22) Next, a method of connecting members according to the second embodiment of the present invention will be described with reference to FIG. 5A and FIG. 5B. The second embodiment is a method of connecting two members using the fiber-reinforced resin-molded members 40 as shown in FIG. 4. The steps shown in FIG. 5A and FIG. 5B are carried out in order.

(23) As shown in FIG. 5A, respective exposed portions 40a of the fiber-reinforced resin-molded members 40 are arranged to be opposite to each other, and a resin block 50 is disposed between the both exposed portions 40a. As a forming material of the resin block 50, it is preferable to use the same material as the material of the matrix resin of the fiber-reinforced resin-molded member 40 for preferable familiarity thereto.

(24) The resin block 50 and a periphery thereof are so heated as to be melted, and the melted resin permeates the both exposed portions 40a, and is also flown through an interface between the fiber-reinforced resin-molded members 40 opposite to each other. The melted resin having flown through the interface between the fiber-reinforced resin-molded members 40 becomes cured, thus connecting the two fiber-reinforced resin-molded members 40 at an interface connected layer 60 formed through curing of the melted resin, thereby producing a connected structural body 100, as shown in FIG. 5B.

(25) According to the illustrated method of connecting the members, since no connecting components such as adhesive and bolts are used, the two fiber-reinforced resin-molded members 40 can be efficiently connected to each other at an inexpensive production cost. When connecting the two fiber-reinforced resin-molded members 40, the fiber-reinforced resin-molded members 40 are connected at the respective exposed portions 40a included in the fiber-reinforced resin-molded members 40, thereby forming the connected portion to contain the fiber-reinforcing material 20 located at the exposed portions 40a ; therefore, it is possible to connect the two fiber-reinforced resin-molded members 40 with high connecting strength.

(26) FIG. 6A and FIG. 6B are drawings showing the third embodiment of the method of connecting the members according to the present invention carried out in the order of FIG. 6A and FIG. 6B.

(27) The connecting method of the third embodiment is a method of preparing the fiber-reinforced resin-molded member 40 and a different resin-molded member 70 including no exposed portion, and connecting the member 40 and the member 70 to each other. As shown in FIG. 6A, a part of the different resin-molded member 70 is so disposed to be opposite to the exposed portion 40a of the fiber-reinforced resin-molded member 40, and subsequently, the opposite portion 70a and a periphery thereof are heated.

(28) By heating the opposite portion 70a and the periphery thereof, the resin located at this position becomes melted, and the melted resin permeates the exposed portion 40a, and is then flown through an interface between the fiber-reinforced resin-molded member 40 and the different resin-molded member 70 that are opposite to each other. The melted resin having flown through the interface between the fiber-reinforced resin-molded member 40 and the different resin-molded member 70 becomes cured, thus connecting the fiber-reinforced resin-molded member 40 and the different resin-molded member 70 at an interface connected layer 80 formed through curing of the melted resin, thereby producing a connected structural body 100A.

(29) By the illustrated method of connecting the members, because of using no connecting components such as adhesive and bolts, it is also possible to efficiently connect the fiber-reinforced resin-molded member 40 and the different resin-molded member 70 to each other at an inexpensive production cost. At the time of connecting the fiber-reinforced resin-molded member 40 and the different resin-molded member 70 to each other, because the fiber-reinforced resin-molded member 40 is provided with the exposed portion 40a where the fiber-reinforcing material 20 is exposed, the connected portion is formed to contain the fiber-reinforcing material 20 at the exposed portion 40a ;

(30) therefore, it is possible to connect the fiber-reinforced resin-molded member 40 and the different resin-molded member 70 to each other with high connecting strength.

(31) Example of the present invention will be described hereinafter. A mold including a cavity for forming a flat plate having a plate thickness of 2 mm was used, and a core was joined at a predetermined position of a cavity surface of the mold. Plain-woven carbon fiber fabric of 400 g/m.sup.2 was disposed in this mold, and then the mold was closed. A temperature of the mold was set at 160 C. As the thermoplastic resin to be supplied in the cavity, a mixture formed by adding a catalyst and an activator to -caprolactam that is a raw material of polyamide was used. The thermoplastic resin was melted at 100 C., and the mold was filled with the melted thermoplastic resin. After being held for ten minutes to polymerize the thermoplastic resin, the mold was opened to release a molded member therefrom. The produced molded member was observed, and it was found that an exposed portion where inner carbon fibers were exposed was formed at a portion where the plain-woven carbon fiber fabric had been pressed by the core. There were prepared two molded members produced in the above manner, and the respective exposed portions thereof were joined to each other through melting and curing of a thermoplastic resin made of the same material, thereby firmly connecting the both molded members to each other.

(32) As described above, the embodiments of the present invention have been described in details with reference to the drawings, but specific configurations of the present invention are not limited to the above embodiments. The embodiments of the present invention may be appropriately changed without departing from the scope of the present invention.