JP2009143172A - Method for molding fiber-reinforced plastic and apparatus for producing fiber-reinforced plastic - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve product quality by suppressing a short pass on the periphery of a core material even when the core material is thick, materializing a uniform resin flow, and preventing the occurrence of a part wherein the core material is not impregnated with the resin. <P>SOLUTION: In a method for molding fiber-reinforced plastic, the core material 2 is set in a molding mold 1 and covered airtightly with a sealing sheet 3, the inside of the sealing sheet is decompressed, and the resin is charged inside the sealing sheet to impregnate the core material with the resin. A clearance filling member is set along the side in the resin flow direction of the core material to block the clearance formed in the side of the core material. The resin is supplied from one side of the inside of the sealing sheet and discharged from the other side to impregnate the core material with the resin. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a fiber reinforced plastic molding method for molding a fiber reinforced plastic by a vacuum pressure resin impregnation molding method or a resin impregnation molding method, and an apparatus for manufacturing the same.

  As a method for producing a large-sized fiber-reinforced plastic molded article with a simple mold, it is possible to produce a large-sized fiber-reinforced plastic molded article by using a vacuum pressure resin impregnated molding method (VaRTM) or a resin impregnation molding method (RTM). Resin Transfer Molding).

  An outline of the vacuum pressure resin impregnation molding method (VaRTM) will be described.

  On the surface plate, for example, a core material formed by laminating carbon fiber, glass fiber or the like is installed, and the outer periphery of the core material is covered with a flexible sealing sheet having airtightness, and the peripheral portion of the sealing sheet is Adhering tightly to a surface plate, evacuating the inside of the sealing sheet and supplying a molten liquid resin from one end, sucking the liquid resin from the other end, flowing the liquid resin inside the sealing sheet, Impregnate the core material.

  When the impregnation of the core material with the resin is completed, the inside is sealed and cured at normal temperature while maintaining the degree of vacuum, or is cured by heating at a predetermined temperature in an oven. After curing, the sealing sheet is peeled off, and a molded product (a core material impregnated with resin and cured) is taken out.

  In the fiber reinforced plastic molding by the above-described vacuum pressure resin impregnation molding method, the core material is covered with a sealing sheet and the inside is evacuated, so if the core material is thick, there is a gap around the core material. End up. The gap perpendicular to the flow of the liquid resin is not a big problem, but the gap parallel to the flow of the liquid resin becomes a short path with a low flow resistance, and the liquid resin flows through the gap and the core There is a problem that the fiber does not flow uniformly in the material and a homogeneous fiber reinforced plastic cannot be molded, or an unimpregnated portion is generated.

  In addition, there exists a thing shown by patent document 1 about the improvement of the resin flow in the shaping | molding method of a fiber reinforced plastic.

JP 2005-271248 A

  In view of such a situation, the present invention suppresses a short path around the core material even when the core material is thick, realizes a uniform resin flow, and produces an unimpregnated portion of resin in the core material. To prevent and improve product quality.

  In the present invention, a core material is installed in a mold, the core material is airtightly covered with a sealing sheet, the inside of the sealing sheet is evacuated, and then a resin is poured into the sealing sheet to impregnate the core material. In the fiber reinforced plastic molding method, a gap filling member is provided along a side surface parallel to the resin flow direction of the core material, the gap generated on the side surface of the core material is closed, and from one of the inside of the sealing sheet The method relates to a method for molding a fiber reinforced plastic in which a resin is supplied and the resin is discharged from the other side so that the core is impregnated with the resin, and the gap filling member is sealed in a vacuumed state. The present invention relates to a method for molding a fiber reinforced plastic that is compressed through a sheet and closes a gap generated on a side surface of the core material in a compressed state.

  The present invention also provides a molding die on which a core material is installed, a gap filling member installed along both sides of the core material, a release sheet that sequentially covers the core material, an impregnation medium, and one of the core materials. The resin supply nozzle disposed on the other side, the resin suction nozzle disposed on the other side, the core material, the gap filling member, the release sheet, the impregnation medium, the resin supply nozzle, and the resin suction nozzle are covered and airtight. A fiber-reinforced plastic comprising: a sealing sheet to be packed; an exhaust device that evacuates the inside of the sealing sheet; a resin supply source connected to the resin supply nozzle; and a resin discharge unit connected to the resin suction nozzle The gap filling member relates to a manufacturing apparatus for fiber-reinforced plastic, which is an open-cell porous highly elastic material.

  According to the present invention, a core material is installed in a mold, the core material is airtightly covered with a sealing sheet, the inside of the sealing sheet is evacuated, and then a resin is poured into the sealing sheet to form the core material. In the method of molding the fiber reinforced plastic to be impregnated, a gap filling member is provided along a side surface parallel to the resin flow direction of the core material, the gap generated on the side surface of the core material is closed, Since the resin is supplied from one side, the resin is discharged from the other, and the core material is impregnated with the resin, a short path of the resin on the side surface of the core material is suppressed, and a uniform resin flow is realized. In addition, an unimpregnated portion of the resin is prevented from occurring in the core material, and the product quality is improved.

  According to the invention, the gap filling member is compressed through the sealing sheet in a vacuumed state, and closes a gap generated on the side surface of the core material in the compressed state. The gap filling member is deformed and exhibits an excellent effect that a good closed state can be obtained regardless of the gap generation state.

  Further, according to the present invention, a molding die in which a core material is installed, a gap filling member installed along both sides of the core material, a release sheet that sequentially covers the core material, an impregnation medium, and the core material Covering the resin supply nozzle disposed on one side, the resin suction nozzle disposed on the other side, the core material, the gap filling member, the release sheet, the impregnation medium, the resin supply nozzle, and the resin suction nozzle Since it includes a sealing sheet for airtight packing, an exhaust device for evacuating the inside of the sealing sheet, a resin supply source connected to the resin supply nozzle, and a resin discharge unit connected to the resin suction nozzle The short path of the resin on the side surface of the core material is suppressed, a uniform resin flow is realized, and an unimpregnated portion of the resin is prevented from occurring in the core material, thereby improving the product quality.

  Further, according to the present invention, since the gap filling member is an open-cell porous highly elastic material, the gap filling member is deformed according to the gap occurrence state, and a good closed state is obtained regardless of the gap occurrence state. It is obtained and exhibits an excellent effect that a short path of the resin on the side surface of the core material is suppressed.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  First, an outline of a fiber reinforced plastic manufacturing apparatus in which the present invention is implemented will be described with reference to FIGS.

  The fiber reinforced plastic manufacturing apparatus 15 includes a molding die 1 on which the core material 2 is installed, a release sheet 3 that covers the core material 2, and a plurality of layers of impregnated media 4a and 4b that are polymerized and applied to the release sheet 3. 2 shows the two layers), the resin supply nozzle 6 disposed along the upper side of the core material 2, the resin supply nozzle 6 disposed along the upper side of the core material 2, and disposed along the lower side of the core material 2. The resin suction nozzle 9 is provided with gap filling members 19 arranged along the both sides of the core material 2 over the entire length of the core material 2.

  The fiber reinforced plastic manufacturing apparatus 15 covers the impregnating media 4a and 4b, the resin supply nozzle 6, the resin suction nozzle 9, and the gap filling member 19, and the periphery is closely attached to the mold 1 and sealed. Further, an upstream liquid feeding tube 7 connected to the resin supply nozzle 6, a resin supply source 8 connected to the upstream liquid feeding tube 7, and a flow rate provided in the upstream liquid feeding tube 7. An adjustment valve 14, a downstream liquid feed tube 11 connected to the resin suction nozzle 9, a vacuum pump 12 connected to the downstream liquid feed tube 11, a trap 13 and a flow rate adjustment valve 18 provided in the downstream liquid feed tube 11. It has.

  The upstream liquid feeding tube 7 and the downstream liquid feeding tube 11 penetrate between the hermetic sheet 5 and the molding die 1, and the penetration portion is hermetically sealed. Alternatively, the upstream liquid feeding tube 7 and the downstream liquid feeding tube 11 pass through the sealing sheet 5 and are hermetically sealed at the penetration portion.

  The mold 1 is a flat plate in the figure, but the shape is selected according to the shape of the target molded product. For example, when producing a molded product having a convex curved surface shape, the shape of the mold 1 has a convex curved surface upward, and the core material 2 is placed so as to closely follow the convex curved surface, Similarly, the release sheet 3, the impregnated media 4 a and 4 b, and the sealing sheet 5 are covered along the curved surface of the mold 1.

  Examples of the material of the release sheet 3 include those that have no affinity with the resin to be molded and easily peel off, for example, fluorine resins such as polytetrafluoroethylene, and the impregnated media 4a and 4b are mesh cloths. As the material, for example, polyethylene, polypropylene or the like is used.

  The plurality of layers of the impregnated media 4a and 4b can be overlapped with each other to increase the gap through which the resin can circulate without increasing the mesh size. Therefore, the flow path cross section of the resin to be supplied can be increased. The impregnation medium 4 may be a single layer as long as the resin can be distributed.

  The gap filling member 19 is preferably a porous material having a large deformability, and the holes are preferably open cells communicating with the outside air. For example, urethane sponge, polyethylene sponge, silicon rubber, or the like, which is a material that does not melt in the molding resin, is used. Further, the cross-sectional shape of the gap filling member 19 is preferably a shape that satisfies the gap 20 formed on both side portions of the core material 2 in a state where the sealing sheet 5 is covered with the core material 2. Moreover, it is preferable that the side surface and the bottom surface of the gap filling member 19 are orthogonal planes so that the side surface of the core material 2 and the surface of the mold 1 are in close contact with each other.

  Further, when the cross-sectional shape of the gap filling member 19 is a shape in which no gap is formed between the gap filling member 19 and the sealing sheet 5 in the sucked state, the gap filling member 19 is made of a solid material such as silicon rubber. Use the one with less deformation.

  The resin supply nozzle 6 and the resin suction nozzle 9 have a tube shape extending in a direction perpendicular to the flow, and the axial length thereof is the same as or slightly shorter than the width of the core material 2. Resin supply ports 16 are formed at a predetermined pitch in the resin supply nozzle 6, and resin suction ports 17 are formed at a predetermined pitch in the resin suction nozzle 9. The resin supply port 16 and the resin suction port 17 are provided downward. By providing at least the resin supply port 16 downward or substantially downward, the flow of resin discharged from the resin supply port 16 is changed from the downward direction to the horizontal direction, and the velocity distribution is changed in the process of changing the flow. Is eliminated, and the uniform speed distribution in the width direction is promoted.

  Liquid resin is supplied from the resin supply nozzle 6 in the axial length of the resin supply nozzle 6, and the resin suction nozzle 9 sucks in the axial length of the resin suction nozzle 9, and the resin supply nozzle 6 A flow of the resin having the width of the axial length is formed from to the resin suction nozzle 9.

  The resin supply nozzle 6, the resin supply port 16 formed in the resin suction nozzle 9, and the resin suction port 17 have a uniform pitch so that the flow rate is uniform over the entire width according to the molding conditions of the fiber reinforced plastic. Set to Further, in the drawing, the upstream liquid feeding tube 7 communicates with the resin supply nozzle 6 at one place, but the upstream liquid feeding tube 7 branches to communicate with the resin supply nozzle 6 at a plurality of places. Also good. Similarly, the downstream liquid feeding tube 11 may communicate with the resin suction nozzle 9 at a plurality of locations.

  The upstream liquid feed tube 7 is provided with the flow rate adjusting valve 14, and the downstream liquid feed tube 11 is provided with the flow rate regulating valve 18 at a required position. The flow rate regulating valve 18 and the flow rate regulating valve 14 are used for resin. The flow rate can be adjusted.

  Hereinafter, the method for molding a fiber reinforced plastic according to the present invention will be described with reference to FIG.

  A mold release agent is applied to the mold 1 and the core material 2 is installed. Examples of the mold release agent include grease such as silicon or fluororesin (STEP: 01).

  The gap filling members 19 and 19 are disposed along the side of the core material 2 (STEP: 02), and the release sheet 3, the impregnating media 4 a and 4 b, and the sealing sheet 5 are attached to the core material 2. Cover sequentially (STEP: 03).

  The impregnated media 4a and 4b are preferably two or more layers in the case of a large size, and the impregnated media 4a provided on at least the core material 2 side is a mesh in consideration of the surface roughness and properties of the finished molded product. Fine-grained items are used. The impregnating medium 4b provided in two or three layers may be a fine mesh having the same fineness as that of the impregnating medium 4a (for example, having 24 or more meshes). A coarser mesh than 4a (for example, the number of meshes is 14 or less) can also be used.

  In addition, by increasing the roughness of the two layers of the impregnating media 4b with respect to the one layer of the impregnating media 4a, a gap formed by the impregnating media 4a and 4b is increased, The mesh pitch changes between the impregnating media 4b, and interference between the meshes is avoided, and the work of superimposing the impregnating media 4a and 4b is facilitated.

  When the installation of the gap filling member 19, the release sheet 3, and the impregnation media 4 a and 4 b is completed, the resin supply nozzle 6 is installed on the upstream side of the core material 2, and the resin on the downstream side of the core material 2. A suction nozzle 9 is installed. Further, the sealing sheet 5 is covered, and the periphery of the sealing sheet 5 is brought into close contact with the mold 1 and sealed. An airtight space 10 for storing the core material 2 is formed between the sealing sheet 5 and the mold 1 (packing) (STEP: 04). In addition, as a method of contact | adhering, a double-sided adhesive tape may be used, or the circumference | surroundings may be pressed with a frame.

  The upstream liquid feed tube 7 is communicated with the resin supply nozzle 6. The resin supply nozzle 6 and the upstream liquid feed tube 7 may be integrated in advance.

  The downstream liquid feeding tube 11 is communicated with the resin suction nozzle 9. Similarly, the downstream liquid feeding tube 11 and the resin suction nozzle 9 may be integrated.

  The upstream liquid feed tube 7 is connected to the resin supply source 8 through the flow rate adjusting valve 14, the downstream liquid feed tube 11 is connected to the vacuum pump 12, and the downstream liquid feed tube 11 has the flow rate adjusted. The valve 18 and the trap 13 are attached. The downstream liquid feeding tube 11 is divided on the upstream side of the flow rate adjusting valve 18 of the downstream liquid feeding tube 11 so that it can be connected via a pipe joint, and the divided downstream liquid feeding tube 11 is connected to the downstream liquid feeding tube 11. The flow rate adjusting valve 18, the trap 13, and the vacuum pump 12 may be integrated into an exhaust / drain unit.

  The upstream liquid feeding tube 7 is closed by the flow rate adjusting valve 14. The flow rate adjusting valve 18 is opened, and the space 10 is evacuated from the vacuum pump 12. The suction time is set to a time during which the air, moisture and the like inside the core material 2 are sufficiently exhausted (STEP: 05).

  By vacuuming, an external pressure is applied to the gap filling member 19 through the sealing sheet 5, and the gap filling member 19 is compressed. The gap filling member 19 is made of an open-celled porous material, so that it is easily compressed, and the gap filling member 19 is deformed according to the gap generation state, and the side surface of the core material 2 and the sealing sheet It compresses and deforms to fill the gap formed between the five. Further, by compressing, the hole in the gap filling member 19 is crushed, and the flow path resistance increases with respect to the resin flow.

  The flow rate adjusting valve 14 of the upstream liquid feeding tube 7 is opened, and the liquid resin is fed to the resin supply nozzle 6 through the upstream liquid feeding tube 7. The liquid resin is dispersed from the resin supply port 16 of the resin supply nozzle 6 and supplied to the space 10. By the suction of the space 10, the sealing sheet 5 is in close contact with the impregnating media 4a and 4b, but a gap through which the liquid resin can flow is secured by the impregnating media 4a and 4b. Since the flow path resistance of the gap filling member 19 is increased, most of the supplied liquid resin is formed in one of the spaces 10, that is, the resin supply nozzle, in the space formed by the impregnating media 4a and 4b. 6 flows in one direction toward the other side, that is, the resin suction nozzle 9. In the process of flowing the impregnating media 4a and 4b, the liquid resin is impregnated into the core material 2 (STEP: 06).

  Excess liquid resin that has passed through the impregnating media 4 a and 4 b is sucked by the resin suction nozzle 9 and collected in the trap 13. Whether or not the liquid resin has completely impregnated the core material 2 is determined in advance by experiments or the like with respect to the time (impregnation time) for the liquid resin to completely penetrate into the core material 2. It is judged by visual inspection whether the core material 2 has been wetted by the liquid resin.

  As described above, since the impregnating media 4a and 4b are formed in a plurality of layers, the gap formed by the impregnating media 4a and 4b, that is, the cross section of the flow path through which the liquid resin flows increases, and the flow rate of the liquid resin increases. The impregnation speed of the resin into the core material 2 is increased, and the impregnation time can be shortened.

  By providing the gap filling member 19 on the side surface of the core material 2, the gap formed on the side surface of the core material 2 is closed. Therefore, the resin suction nozzle is short-passed on the side surface of the core material 2. 9 can suppress the liquid resin sucked by 9 and eliminate the short path, so that the flow velocity distribution of the liquid resin flowing through the core material 2 or the impregnating media 4a and 4b can be made uniform. It can prevent that an unimpregnated part arises. Furthermore, since there is no liquid resin that is short-passed, the amount of resin used in the impregnation step is reduced.

  When the set impregnation time elapses, the flow rate adjusting valve 14 is closed and the flow rate adjusting valve 18 is closed to stop the supply of the liquid resin.

  In the state where the space 10 is kept airtight, that is, in a state where the pressure is reduced, the upstream liquid feeding tube 7 is divided to separate the resin supply source 8 from the sealing sheet 5 and the resin supply nozzle 6. Further, the downstream liquid feeding tube 11 is divided upstream of the flow rate adjusting valve 18 of the downstream liquid feeding tube 11, and the sealing sheet 5, the resin suction nozzle 9 and the flow rate adjusting valve 18 are separated. The reason why the airtightness is maintained is that the thickness of the molded product becomes thick because the airtightness cannot be maintained unless the vacuum is maintained.

  The impregnated resin is cured. The curing of the resin is appropriately selected depending on the material of the impregnated resin and the shape of the molded product, such as when performing curing at normal temperature or when performing heat curing at 100 ° C. to 120 ° C. (STEP: 07).

  When heat-curing is performed, the core 2 is packed in the mold 1 and placed in a furnace and heated for a required time.

  When the curing is completed, the sealing sheet 5, the impregnated media 4a and 4b, and the release sheet 3 are peeled off, the gap filling member 19 is removed, and the finished molded product is taken out (STEP: 08).

  5A shows a state in which the liquid resin in the case where the present invention is not carried out is impregnated in the core material 2, and FIG. 5B shows that the liquid resin in the case where the present invention is carried out is the core material 2. The state of impregnation is shown, and it can be seen that the resin is uniformly impregnated by carrying out the present invention. Therefore, the generation of unimpregnated portions is prevented.

  Next, FIG. 6 shows the case where a fiber reinforced plastic is molded using a mold according to the present invention, and FIG. 6 shows the case where it is cut in a plane perpendicular to the resin flow.

  In FIG. 6, reference numeral 21 denotes a lower mold, 22 denotes an upper mold, and the lower mold 21 and the upper mold 22 overlap each other.

  In a state where the core material 2 is housed in the recess 23 of the lower mold 21, a gap 24 is left around the core material 2 (FIG. 6A), and the resin flow is parallel to the surrounding gap. The filling member 25 is inserted into the extending gap (FIG. 6B).

  The filling member 25 is inserted into the gap 24, preferably restored in a state of being press-fitted, and is preferably in close contact with the side surface of the core member 2 and the wall surface of the recess 23, and has an appropriate hardness so that insertion and press-fitting are possible. A material that has elasticity and deformability and does not melt into the molding resin is used. As a material of the filling member 25, for example, silicon rubber or the like is used.

  Liquid resin is sucked into the recess 23 to impregnate the core material 2 with the liquid resin. Alternatively, a pressurized liquid resin is injected into the recess 23 to impregnate the core material 2 with the liquid resin.

  In any case, since the gap 24 is closed by the filling member 25, the liquid resin does not short-pass the side surface of the core material 2, the resin flow is made uniform, and the resin with respect to the core material 2 is The generation of unimpregnated parts is prevented and the amount of resin used is saved.

It is a schematic sectional drawing which shows embodiment of this invention. It is a top view which shows embodiment of this invention. FIGS. 2A and 2B are views taken along the line A-A in FIG. 1, in which FIG. 1A illustrates a state in which a gap is generated, and FIG. It is a flowchart which shows the outline of the shaping | molding method of the fiber reinforced plastic which concerns on embodiment of this invention. It is the figure which modeled the flow of the liquid resin in shaping | molding of a fiber reinforced plastic, (A) is the flow of the liquid resin in shaping | molding of the conventional fiber reinforced plastic, (B) is the fiber reinforced plastic of this invention. The flow of liquid resin in molding is shown. It is explanatory drawing which shows other embodiment of this invention, (A) has shown the state in which the clearance gap produced, (B) has shown the state which provided the clearance gap filling member in the clearance gap.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Mold 2 Core material 3 Release sheet 4a, 4b Impregnation media 5 Seal sheet 6 Resin supply nozzle 7 Upstream liquid feed tube 8 Resin supply source 9 Resin suction nozzle 10 Space 11 Downstream liquid feed tube 12 Vacuum pump 13 Trap 14 Flow rate adjustment valve DESCRIPTION OF SYMBOLS 15 Fiber reinforced plastic manufacturing apparatus 16 Resin supply port 17 Resin suction port 18 Flow regulating valve 19 Gap filling member 25 Filling member

Claims (4)

  A fiber reinforced plastic is provided in which a core material is installed in a mold, the core material is airtightly covered with a sealing sheet, the inside of the sealing sheet is evacuated, and then the resin is poured into the sealing sheet to impregnate the core material. In the molding method, a gap filling member is provided along a side surface parallel to the resin flow direction of the core material, the gap generated on the side surface of the core material is closed, and the resin is supplied from one side of the sealed sheet. A method for molding a fiber reinforced plastic, wherein the resin is discharged from the other side and the core material is impregnated with the resin.   The method for molding a fiber reinforced plastic according to claim 1, wherein the gap filling member is compressed through the sealing sheet in a vacuumed state, and closes a gap generated on a side surface of the core member in the compressed state.   A molding die in which a core material is installed, a gap filling member installed along both sides of the core material, a release sheet that sequentially covers the core material, an impregnation medium, and a resin disposed on one of the core materials A supply nozzle, a resin suction nozzle disposed on the other side, a core sheet, the gap filling member, the release sheet, the impregnation medium, the resin supply nozzle, and a sealing sheet that covers the resin suction nozzle and is airtightly packed A fiber reinforced plastic comprising: an exhaust device that evacuates the inside of the sealing sheet; a resin supply source connected to the resin supply nozzle; and a resin discharge unit connected to the resin suction nozzle. Manufacturing equipment.   The apparatus for producing fiber-reinforced plastic according to claim 3, wherein the gap filling member is an open-cell porous highly elastic material.

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