FRP molding mold, and FRP molding system and method using same

Abstract

An inner-surface mold 10A or an outer-surface mold 10B of a FRP molding mold 10 comprises a mold body 12, a partial-drive mold 14, and a partial-drive device 16. The partial-drive mold 14 is attached to the mold body 12 and is configured to be movable in a pressing direction in which pressure is applied to the molding surface of the FRP material 2. The partial-drive mold 14 is a solidified-part mold 14a or a thick-part mold 14b. The partial-drive device 16 drives the partial-drive mold 14 independently relative to the mold body 12 and applies pressure to the FRP material 2, and heats the FRP material 2 under pressure to convert the FRP material into FRP.

Description

FRP molding die and FRP molding system and method using same

[0001] The present invention relates to a method for producing an FRP product by molding an FRP material containing a resin and reinforcing fibers.

[0002] Fiber-reinforced composite materials, such as CFRP (carbon fiber reinforced plastic), have lower density than metal materials such as iron and aluminum, yet have excellent mechanical properties, high specific strength, and are light and strong. For this reason, in recent years, they have been used as structural members in aircraft, small boats, automobiles, etc., as an alternative to aluminum alloys. Hereinafter, fiber-reinforced composite materials will be simply referred to as "FRP."

[0003] For example, aircraft structures (fuselages, hatches, wings, etc.) have traditionally been made by joining aluminum alloys together with rivets. However, joining using rivets is difficult to do, and when applied to FRP, the internal fibers are cut, resulting in a significant decrease in tensile strength. To solve this problem, for example, Patent Documents 1 and 2 have been proposed.

[0004] The "Manufacturing Method for FRP Molded Products" of Patent Document 1 involves placing a sheet-like FRP material containing a thermoplastic resin and reinforcing fibers on a surface mat so that they overlap, and then heating the material using a heating device. The FRP material is then transported while still on the surface mat and set in a mold of a press. The press then applies pressure to the overlapping FRP material and surface mat, producing an FRP molded product in which the reinforcing fibers and surface mat are integrated with the thermoplastic resin.

[0005] The "FRP Molding System and Method" of Patent Document 2 produces an arc-shaped FRP product by integrally molding an FRP material having an arc portion and a member fixed thereto. This system includes a partial press device, a member positioning mechanism, and a conveying device. The partial press device has upper and lower molds that clamp a portion of the FRP material in a radial direction perpendicular to the arc portion, and intermittently compresses a portion of the FRP material to partially mold the FRP product. The member positioning mechanism positions the member relative to the upper or lower mold. The conveying device intermittently moves the portion of the FRP material compressed by the partial press device.

[0006] JP 2015-009396 A International Publication No. 2022 / 044324

[0007] In order to turn FRP materials into FRP products, it is necessary to impregnate fibers (e.g., carbon fibers) with resin, and for this purpose, it is effective to apply pressure when the viscosity of the resin is low. In Patent Documents 1 and 2, when an FRP material containing a thermoplastic resin and reinforcing fibers is heated under pressure using a press and a mold to reduce the viscosity of the resin, and then cooled under pressure to form an FRP product, the following problems arise.

[0008] (1) When the viscosity of the thermoplastic resin is reduced, the specific volume of the FRP material increases due to thermal expansion, and when it solidifies, the specific volume decreases. Therefore, if pressure is applied flush to the part with reduced viscosity (for example, the molten part) and the solidified part where the viscosity has not decreased, sufficient pressure will not be applied to the solidified part, and internal defects will occur in the intermediate part (transition part).

[0009] (2) When an FRP product has a section with a varying thickness, the resin contained in the FRP material pressurized between the upper and lower molds becomes fluid due to a decrease in viscosity, filling the space between the upper and lower molds without any gaps. If the pressurized state is then maintained until the thermoplastic resin solidifies, the amount of shrinkage upon solidification is small in the thin-walled sections and large in the thick-walled sections. As a result, sufficient pressure is not applied to the thick-walled sections, resulting in internal defects in the thick-walled sections.

[0010] The present invention has been devised to solve the above-mentioned problems. That is, an object of the present invention is to provide an FRP molding die that can heat a resin-containing FRP material under pressure to mold an FRP product with few internal defects, and an FRP molding system and method using the same.

[0011] According to the present invention, there is provided an FRP molding die for heating an FRP material containing resin under pressure to form FRP, the FRP molding die having an inner mold and an outer mold that hold the FRP material therebetween, the inner mold or the outer mold comprising: a mold body; a partial drive mold attached to the mold body and movable in a pressing direction that applies pressure to the molding surface of the FRP material; a partial drive device that can drive the partial drive mold independently of the mold body; and a heating device that can heat the mold body.

[0012] Furthermore, according to the present invention, there is provided an FRP molding system comprising: a partial pressing device having a bolster and a slide for fixing the above-mentioned FRP molding die, and intermittently compressing a portion of the FRP material to partially mold the FRP product; and a conveying device for intermittently moving the portion of the FRP material compressed by the partial pressing device.

[0013] Furthermore, according to the present invention, there is provided an FRP molding method, which comprises gripping the FRP material between the inner mold and the outer mold of the above-mentioned FRP molding mold, driving the mold body and the partially driven mold independently of each other to apply pressure to the FRP material, and heating the FRP material under pressure to convert it into FRP.

[0014] According to the configuration of the present invention, an FRP molding die includes a partial drive device capable of driving a partial drive die independently of the die body, and a heating device capable of heating the die body. With this configuration, even if the specific volume (e.g., thickness) of the FRP material increases due to thermal expansion in the heating section (e.g., molding zone) heated by the heating device, the molding outer surface of the partial drive die can be driven independently of the die body. This allows sufficient pressure to be applied to the entire molding surface of the FRP material during the process of converting the FRP material into FRP, preventing or suppressing the occurrence of internal defects and allowing the molding of FRP products with fewer internal defects.

[0015] 1B is a perspective view of a representative FRP product manufactured by the present invention; FIG. 1C is a side cross-sectional view of the FRP product; FIG. 1D is an end view of the FRP product; FIG. 1E is a partially enlarged view of FIG. 1C; FIG. 1F is a front view of an FRP molding system according to the present invention; FIG. 1G is a view of a first embodiment of an inner mold, and is an enlarged cross-sectional view of the inner mold of FIG. 3; FIG. 1H is a functional explanatory diagram of a solidification section mold; FIG. 1J is a functional explanatory diagram of a thick section mold; FIG. 1J is an explanatory diagram of a fixing structure of a partial fixing mold; FIG. 1J is an explanatory diagram of a fixing structure of a thick section mold; FIG. 1H is a view of a second embodiment of an inner mold, and is an enlarged cross-sectional view of the inner mold of FIG. 3; FIG. 1J is an explanatory diagram of a method for repeating partial molding; FIG. 1J is another explanatory diagram of a method for repeating partial molding; FIG. 1C is an overall flow diagram of an FRP molding method according to the present invention; FIG. 1C is a view of another example of a circular arc section; FIG. 1D is an explanatory diagram of variations in press mechanisms and mold arrangements.

[0016] Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. Note that common parts in the drawings are given the same reference numerals and redundant explanations will be omitted.

[0017] The FRP molding system 100 of the present invention is an apparatus that molds an FRP material 2 to produce an arc-shaped FRP product 3 with a radius of 1 m or more. The FRP material 2 is a material that is made by laminating multiple prepregs 1 and becomes the FRP product 3 after molding. "Prepregs 1" are intermediate materials in which a base material made of reinforcing fibers (e.g., glass fibers or carbon fibers) is impregnated with resin.

[0018] In the present invention, the resin is preferably a thermoplastic resin, which is broadly classified into crystalline resin and amorphous resin. Resins are composed of long, string-like polymers entangled together. Crystalline resins and amorphous resins differ in the aggregation state of the polymer chains.

[0019] Crystalline resins have "amorphous parts" where polymer chains are irregularly entangled, and "crystalline parts" where they are regularly arranged. When the temperature is raised, the temperature at which the molecular motion of the amorphous parts becomes active is the glass transition temperature (Tg), and the temperature at which the crystalline parts begin to flow is the melting point (Tm). An example of a crystalline resin is PEEK (polyether ether ketone). The melting point of PEEK is approximately 340°C.

[0020] Amorphous resins have "amorphous parts" where polymer chains are irregularly entangled. Amorphous resins do not have a clear melting point, and once the Tg is exceeded, the molecular movement of the polymer chains becomes active. An example of an amorphous resin is PEI (polyetherimide). The glass transition temperature of PEI is approximately 220°C.

[0021] Thermoplastic resins are solidified at room temperature. The resin is preferably a thermoplastic resin, but may be a thermosetting resin. Hereinafter, the thermoplastic resin will be described, and unless necessary, the thermoplastic resin will be simply referred to as "resin."

[0022] In order to turn the FRP material 2 into the FRP product 3, it is necessary to apply pressure to the resin while the viscosity of the resin is low, so that the resin is impregnated into the fibers (for example, carbon fibers).

[0023] 1A to 1C are explanatory diagrams of an FRP material 2 and an FRP product 3. The FRP material 2, which contains a thermoplastic resin, is heated under pressure to reduce the viscosity of the resin, and then cooled to form the FRP product 3. The shapes of the FRP material 2 before molding and the FRP product 3 after molding are substantially identical. Hereinafter, converting part or all of the FRP material 2 into the FRP product 3 will be referred to as "FRP conversion."

[0024] FIG. 1A is a representative perspective view of an FRP material 2 and an FRP product 3, FIG. 1B is a side cross-sectional view, and FIG. 1C is an end view.

[0025] "Arc-shaped FRP product 3 with a radius of 1 m or more" refers to a large FRP product such as an aircraft fuselage. The radius is, for example, 2 m, but may be 1 to 10 m. The axial length (length in the axial direction) is, for example, 8 m, but may be 10 cm to 20 m.

[0026] 1A, the "arc-shaped" refers to an arc having a constant radius, but the radius may not be strictly constant and may vary partially or continuously. The circumferential angle of the arc (arc angle) is preferably 180 degrees or less, but may exceed 180 degrees as long as it does not interfere with the press frame 34 described below.

[0027] In this example, the FRP material 2 and the FRP product 3 each have an arc-shaped arc portion 5 and a member 6 fixed to the arc portion 5. In this example, the members 6 are multiple stringers 6 fixed to the arc portion 5 and extending parallel to each other in the axial direction. The members 6 may be fixed to either the inner surface (the inner circumferential surface, which in the case of an aircraft fuselage is a concave portion that becomes the inner circumferential surface) or the outer surface (the outer circumferential surface, which in the case of an aircraft fuselage is a convex portion that becomes the outer circumferential surface) of the arc portion 5. In this example, the shape of the arc-shaped arc portion 5 and the member 6 fixed to the inner surface of the arc portion 5 will be described. Furthermore, the member 6 is not limited to a stringer 6 and may be other members, such as a channel with an L-shaped or Z-shaped cross section. Note that the "axial direction" is not limited to a strict axial direction and may be inclined relative to the axial direction. Furthermore, the radial thickness of the arc portion 5 is preferably constant, but may vary partially or continuously. For example, it may include a window frame or door portion of an aircraft fuselage.

[0028] For example, the FRP material 2 may have an arc-shaped arc portion 5 and a member 6 fixed to the outer surface of the arc portion 5. In this case, it is preferable that the molding outer surface of the inner mold has an inner arc surface that comes into close contact with the arc portion 5, and the molding outer surface of the outer mold has an outer arc surface that comes into close contact with the outer surface of the FRP material 2 and an outer groove that fits into the outer surface shape of the member 6.

[0029] Alternatively, the FRP material 2 may have an arc-shaped arc portion 5, the outer molding surface of the inner mold having an inner arc surface F1 that comes into close contact with the arc portion 5, and the outer molding surface of the outer mold having an outer arc surface F3 that comes into close contact with the outer surface of the FRP material 2. Alternatively, the FRP material 2 may have an arc-shaped arc portion 5, the outer molding surface of the inner mold having an inner arc surface F1 that comes into close contact with the outer surface of the FRP material 2, and the outer molding surface of the outer mold having an outer arc surface F3 that comes into close contact with the arc portion 5.

[0030] 12 is a diagram showing another example of the arc portion 5. In this figure, (A) is a side view, and (B) and (C) are cross-sectional views taken along the line B-B of (A). As shown in this figure, the FRP material 2 has an arc-shaped arc portion 5, and the cross-sectional shape of the arc portion 5 may be Z-shaped, L-shaped, or flat.

[0031] 2 is a partially enlarged view of FIG. 1C. As shown in this figure, the arc portion 5 of the FRP material 2 is a laminate that matches the thickness distribution of the arc portion 5 of the FRP product 3. The arc portion 5 is preferably laminated to match the arc-shaped molded shape. Furthermore, the stringer 6 of the FRP material 2 is a laminate, molded product, or preform that is bent to match the cross-sectional shape of the stringer 6 of the FRP product 3.

[0032] The thickness of the arc portion 5 of the FRP material 2 corresponds to the radial thickness of the arc portion 5 of the FRP product 3, and is set according to the thickness after molding. It is also preferable to change the number of layers of the prepreg 1 according to the thickness of the FRP product 3. The same applies to the stringer 6 of the FRP material 2.

[0033] In Figure 2, the stringer 6 has a removable mandrel 8 sandwiched between it and the arc portion 5, with both circumferential ends held by the inner surface of the arc portion 5. The mandrel 8 preferably has a trapezoidal cross section and has an upper surface 8a, a sloped surface 8b, and a bottom surface 8c. The bottom surface 8c is preferably an arcuate surface that matches the inner surface of the arc portion 5. The mandrel 8 may have either an integral structure or a divided structure. "Integral structure" means a structure that is not divided.

[0034] 2, the stringer 6 has an upper surface portion 7a that fits closely to the trapezoidal upper surface 8a of the mandrel 8, a pair of side surfaces 7b that fit closely to the sloped surfaces 8b of the trapezoid, and a pair of legs 7c that extend outward from the lower ends of the side surfaces 7b and fit closely to the inner surface of the arc-shaped portion 5B. The pair of legs 7c are held on the inner surface of the arc-shaped portion 5B. This holding is achieved by positioning the stringer 6 by placing it over the mandrel 8, or, if necessary, by temporarily attaching the legs 7c to the arc-shaped portion 5B, for example, by welding them.

[0035] The cross-sectional shape of the stringer 6 is not limited to a trapezoid, and may be another shape, such as a triangle or a dome shape with an arc-shaped upper part. Similarly, the mandrel 8 may also have a shape other than a trapezoid, depending on the cross-sectional shape of the stringer 6.

[0036] The arc portion 5 and the stringer 6 are both made of FRP material 2, and can be molded as a single unit. The role of the mandrel 8 is to prevent the shape from collapsing when molding pressure is applied. For this reason, it is preferable to use a mandrel 8 for a hollow structured member 6. It is also preferable to use a mandrel 8 when the other end of the stringer 6 is open, such as when the cross section of the stringer 6 is L-shaped or Z-shaped.

[0037] FIG. 3 is a front view of the FRP molding system 100 according to the present invention, showing the molding in progress.

[0038] In FIG. 3, the FRP molding system 100 includes an FRP molding die 10 , a partial pressing device 30 , and a conveying device 40 .

[0039] The FRP molding die 10 has an inner die 10A (upper die in this figure) and an outer die 10B (lower die in this figure) that hold the FRP material 2 and FRP product 3 therebetween. In this example, the inner die 10A and outer die 10B vertically sandwich a portion (press portion) of the FRP material 2 between them. The inner die 10A has an inner arc surface F1 that comes into close contact with the arc portion 5, and an inner groove F2 that fits into the top surface shape of the member 6. The outer die 10B has an outer arc surface F3 that comes into close contact with the outer surface of the FRP material 2.

[0040] The partial pressing device 30 intermittently compresses a portion (pressed portion) of the FRP material 2 in a radial direction (vertical direction in the drawing) perpendicular to the arc portion 5 of the FRP material 2 to partially form the FRP product 3. "Intermittent compression" means that the partial pressing device 30 and the conveying device 40 repeatedly compress and convey the FRP material 2.

[0041] The partial pressing device 30 compresses a portion of the FRP material 2 using the inner mold 10A and the outer mold 10B. In this example, the partial pressing device 30 has a bolster 31 to which the inner mold 10A is fixed on the lower surface, a slide 32 to which the outer mold 10B is fixed on the upper surface, a hydraulic ram 33 that moves the slide 32 up and down, and a press frame 34 to which the bolster 31 and the hydraulic ram 33 are fixed.

[0042] In this example, the partial press device 30 pushes up the outer surface mold 10B (lower mold in the figure) against the inner surface mold 10A (upper mold in the figure) to compress the pressed portion of the FRP material 2. In this case, the partial press device 30 compresses the pressed portion in the diameter direction of the FRP material 2. The press frame 34 has an upper structure configured so as not to interfere with the FRP material 2 when intermittently moving the compressed portion of the FRP material 2. Note that the vertical relationship of the bolster 31, slide 32, and hydraulic ram 33 may be reversed, as long as there is no interference between the FRP material 2 and the press upper structure. In other words, the slide 32 and hydraulic ram 33 may be at the top, and the bolster 31 at the bottom.

[0043] Figure 13 is an explanatory diagram of variations in the press mechanism and die arrangement. Figure 13(A) shows the first variation shown in Figure 3. In this example, the inner die 10A is positioned above the FRP material 2 and the outer die 10B is positioned below it, and the partial pressing device 30 pushes the outer die 10B up against the inner die 10A to compress the pressed portion of the FRP material 2.

[0044] Figure 13(B) shows a second variation in which the press mechanism is arranged in the same manner as in Figure 3, but the mold arrangement is reversed from that in Figure 3. In this example, the inner mold 10A is positioned below the FRP material 2 and the outer mold 10B is positioned above it, and the partial pressing device 30 pushes the inner mold 10A up against the outer mold 10B to compress the pressed portion of the FRP material 2.

[0045] Figure 13(C) shows a third variation in which the layout of the press mechanism and the layout of the molds are reversed from those in Figure 3. In this example, the inner mold 10A is positioned below the FRP material 2 and the outer mold 10B is positioned above it, and the partial pressing device 30 presses the outer mold 10B down against the inner mold 10A to compress the pressed portion of the FRP material 2.

[0046] Figure 13(D) shows a fourth variation in which the arrangement of the press mechanism is reversed from that of Figure 3, but the arrangement of the dies is the same as that of Figure 3. In this example, the inner die 10A is positioned above the FRP material 2 and the outer die 10B is positioned below, and the partial pressing device 30 presses the inner die 10A down against the outer die 10B to compress the pressed portion of the FRP material 2.

[0047] The conveying device 40 intermittently moves the compressed portion (pressed portion) of the FRP material 2 by the partial pressing device 30. The conveying device 40 has a gripping device 42 and a moving device 44. The gripping device 42 partially grips the FRP material 2 or the FRP product 3. The moving device 44 moves the gripping device 42 in the moving direction X of the FRP material 2.

[0048] In this example, the movement direction X of the FRP material 2 is the circumferential direction along the arc of the FRP product 3. The movement device 44 is, for example, an articulated robot, and the gripping device 42 is a robot hand. Hereinafter, the horizontal direction perpendicular to the movement direction X will be referred to as the width direction Y, and the up-down direction perpendicular to the width direction Y will be referred to as the pressure direction.

[0049] In this example, a pair of conveying devices 40 are provided on the upstream and downstream sides of the partial pressing device 30, but they may be provided on only one side, either the upstream or downstream side. The gripping device 42 grips the FRP material 2 or the FRP product 3. In this case, the gripped portion may be moved during compression by the partial pressing device 30, for example.

[0050] Fig. 4 is a diagram showing a first embodiment of an inner mold 10A (upper mold in this figure), and is an enlarged cross-sectional view of the inner mold 10A in Fig. 3. In this figure, the inner mold 10A includes a mold body 12, a partially driven mold 14, a partially driven device 16, and a heating device 18.

[0051] 4, the FRP material 2 has a relatively thin portion 2a and a thick portion 2b that is thicker than the thin portion 2a. The thin portion 2a corresponds to only the arc portion 5 in FIG. 2, and the thick portion 2b corresponds to the overlapping portion between the arc portion 5 and a pair of legs 7c in FIG. 2.

[0052] The die body 12 of the inner die 10A is fixed directly to the lower surface of a bolster 31 of a press device (in this example, a partial press device 30). The outer die 10B is fixed directly to the upper surface of a slide 32 of the partial press device 30.

[0053] The partially driven mold 14 is attached to the mold body 12 so as to be movable in a pressing direction that applies pressure to the molding surface of the FRP material 2. The partially driven mold 14 is a partially driven mold that extends across substantially the entire width direction (Y direction) of the mold body 12. In this example, the partially driven mold 14 has a solidification portion mold 14a and a thick portion mold 14b.

[0054] The inner mold 10A and the outer mold 10B have outer molding surfaces that come into contact with the molding surface of the FRP material 2. The outer molding surfaces of the inner mold 10A and the outer mold 10B have a molding zone Za and a non-molding zone Zb. The molding zone Za is the area where the FRP material 2 at the contacting portion is converted into FRP. The non-molding zone Zb is located adjacent to and outside the molding zone Za and is the area where the FRP material 2 or FRP product 3 is preheated or cooled. The non-molding zone Zb is further divided into a preheating zone where the FRP material 2 or FRP product 3 is preheated, and a cooling zone where the FRP material 2 or FRP product 3 is cooled.

[0055] In this example, the molding outer surface G of the inner mold 10A is made up of the molding outer surfaces G1, G2, and G3 of the solidifying portion mold 14a, the thick portion mold 14b, and the partial fixed mold 15. The molding outer surfaces G1 and G3 of the solidifying portion mold 14a and the partial fixed mold 15 form the inner arc surface F1 that comes into close contact with the above-mentioned arc portion 5. The molding outer surface G2 of the thick portion mold 14b forms the inner groove F2 that fits into the upper surface shape of the above-mentioned member 6. It should be noted that the present invention is not limited to this configuration, and a portion of the mold body 12 may form the molding outer surface G of the inner mold 10A.

[0056] The solidification mold 14a is located in the non-molding zone Zb. The solidification mold 14a has a molding outer surface G1 (the lower surface in this figure) that is in close contact with the inner surface of the thin-walled portion 2a (the arc portion 5 in FIG. 2), and is located within a groove provided in the mold body 12 so as to be movable in the pressing direction.

[0057] The thick-walled portion mold 14b forms the thick-walled portion 2b. The thick-walled portion 2b is the portion where another part is joined, for example, the portion where the arc portion 5 and the leg portion 7c in Figure 2 overlap. Note that the thick-walled portion 2b is not limited to this example and may be any portion with a relatively large thickness. The thick-walled portion mold 14b has an outer surface (the lower surface in this figure) that comes into close contact with the outer surface of the stringer 6 in Figure 2, and is positioned within a groove provided in the mold body 12 so as to be movable in the pressing direction.

[0058] The partial driving device 16 is a driving device that can drive the partially driven mold 14 independently of the mold body 12. It is preferable that a plurality of partial driving devices 16 (preferably three or more) are provided at intervals in the width direction (Y direction) of the mold body 12 with respect to the partially driven mold 14. The partial driving device 16 has a rod-shaped member 16a, a linear motion device 16b, and a first pressing control device 16c.

[0059] The rod-shaped member 16a is a shaft having one end (the lower end in the figure) fixed to the partially driven mold 14 and extending in the opposite direction to the pressing direction. The linear motion device 16b is a device fixed to the mold body 12 and moves the other end of the rod-shaped member 16a in the pressing direction. In this example, the linear motion device 16b is a hydraulic cylinder, but it may also be a pneumatic cylinder. The first pressing pressure control device 16c is a device that controls the linear motion device 16b to adjust the pressure acting on the molding surface of the FRP material 2. The first pressing pressure control device 16c is, for example, a hydraulic unit or a pneumatic unit. The first pressing pressure control device 16c is installed outside the mold body 12 and is connected to each linear motion device 16b via piping (not shown).

[0060] In this example, a pair of direction-changing members 17a, 17b are provided between the solidification section mold 14a and the linear motion device 16b. The direction-changing members 17a, 17b each have tapered surfaces that slide against each other, and the sliding of the tapered surfaces acts as a cam that changes the direction of movement of the direction-changing member 17a caused by the linear motion device 16b to the direction of movement of the direction-changing member 17b. This configuration allows the overall height of the mold body 12 to be set low. In this example, the thick-walled section mold 14b is directly connected to the linear motion device 16b via the rod-shaped member 16a.

[0061] In this example, the heating device 18 is disposed inside the mold body 12 and heats the mold body 12. The heating device 18 is configured to be able to heat the thermoplastic resin to a molding temperature that reduces the viscosity of the thermoplastic resin. The heating device 18 is, for example, a cartridge heater, and is disposed inside the mold body 12 so as not to interfere with the partial drive device 16. Note that the heating device 18 may also be other heaters, such as an induction heater or a sheath heater. The power supply and control device for the heating device 18 are installed outside the mold body 12 and are connected to the heating device 18 via wiring (not shown).

[0062] For crystalline resins, the molding temperature is set higher than the melting point but within a range where the resin does not thermally decompose. For example, it is preferably 10°C to 110°C higher than the melting point. For example, for PEEK, the melting point is approximately 340°C, and the molding temperature is preferably approximately 350°C to 450°C. For amorphous resins, the molding temperature is set higher than the glass transition temperature but within a range where the resin does not thermally decompose. For example, for PEI, the glass transition temperature is approximately 220°C, and the molding temperature is preferably approximately 300°C to 400°C. Note that the above molding temperatures are just examples and will vary depending on the type of resin, viscosity, required mechanical properties, molding time, and molding pressure.

[0063] In FIG. 4, the inner mold 10A further includes a partial fixed mold 15 and a cooling device 19.

[0064] The partial fixed mold 15 is detachably attached directly to the mold body 12 in the molding zone Za. The partial fixed mold 15 has a molding outer surface G3 that abuts against the molding surface of the FRP material 2. The molding outer surface G3 of the partial fixed mold 15 has an arbitrary shape that corresponds to the shape of the molding surface of the FRP material 2. The partial fixed mold 15 has the advantage that when the plate thickness distribution differs depending on the molding range, it can be replaced and molding can be performed without replacing the mold body.

[0065] The cooling device 19 has the function of cooling the mold body 12. The cooling device 19 is, for example, a water-cooled or air-cooled heat exchanger, and is arranged inside the mold body 12 so as not to interfere with the partial drive device 16 and the heating device 18. A refrigerant supply source and a control device for the cooling device 19 are installed outside the mold body 12 and are connected to the cooling device 19 via piping (not shown).

[0066] The configuration of the outer mold 10B may be the same as or different from the inner mold 10A.

[0067] (Function of the solidification mold 14a) Fig. 5 is a diagram illustrating the function of the solidification mold 14a. In this example, the thickness of the FRP material 2 and the FRP product 3 is constant.

[0068] 5A shows a conventional example that does not use a solidification mold 14a. An FRP blank 2 of a uniform thickness is held between an upper mold and a lower mold, and the upper and lower molds are heated to heat the FRP blank 2 between them and melt it. In this case, low-temperature zones (corresponding to non-molding zones Zb) with relatively low temperatures and little expansion are generated at the ends of the upper and lower molds, and a transition zone is generated between these zones and the melted zone (corresponding to molding zone Za) that melts and expands. The amount of expansion is, for example, about 3% by volume.

[0069] The transition zone has an intermediate temperature between the low-temperature zone and the molten zone, and is in a state where viscosity begins to decrease. In this transition zone, the upper and lower molds cannot follow the volumetric changes of the FRP material 2 or FRP product 3, and a gap is created between the FRP material 2 or FRP product 3. In this state, if the low-temperature zone in the transition zone is the FRP material 2 or FRP product 3, the heat input releases residual stress from the previous molding, causing the layers to meander out of plane. Alternatively, microvoids present inside the resin or between the resin and the fibers expand. As a result, voids are created inside the resin, between the resin and the fibers, or both. Because the resin is not completely melted in the transition zone and load is not transmitted from the mold, the voids are not filled, resulting in internal defects.

[0070] Figure 5(B) is a schematic diagram of molding using the solidification mold 14a of the present invention, showing the state in which the solidification mold 14a is driven and pressed down independently of the upper mold. With this configuration, when the low-temperature portion of the transition section is the FRP product 3, residual stress from the previous molding is not released, preventing out-of-plane meandering of the layers. Furthermore, even when the low-temperature portion is the FRP material 2 and the FRP product 3, pressure is applied by the solidification mold 14a, preventing the expansion of microvoids present inside the resin or between the resin and the fibers. In this state, as shown in Figure 5(B), a step corresponding to the thermal expansion difference occurs between the solidification mold 14a and the upper mold.

[0071] Figure 5(C) is a schematic diagram of the state after molding using the solidification mold 14a of the present invention, showing the state after the mold has cooled from the state shown in Figure 5(B) and the FRP material 2 and FRP product 3 have solidified. Between Figures 5(B) and 5(C), pressure is applied by the solidification mold 14a and the upper and lower molds. As the temperatures of the melting and transition zones decrease, the amount of thermal expansion decreases, and the entire zone becomes a low-temperature zone, eliminating the step between the solidification mold 14a and the upper mold.

[0072] If the resin is a crystalline resin, the temperature of the FRP material 2 and FRP product 3 at the high-temperature end of the solidification mold 14a should be maintained at +0°C to +110°C, preferably +10°C to +20°C, relative to the melting point of the thermoplastic resin, while the temperature at the low-temperature end should be maintained at -0°C to -300°C, preferably -20°C to -30°C. If the resin is an amorphous resin, the temperature gradient on the molding surface of the solidification mold 14a should be set, for example, lower than the glass transition temperature on the low-temperature side and higher than the glass transition temperature on the high-temperature side. In the case of an amorphous resin, the low-temperature side may be set higher than the glass transition temperature. This temperature gradient is preferably controlled by the heating device 18 on the low-temperature side and the high-temperature side around the solidification mold 14a. Temperature measurement is preferably performed by inserting a thermocouple inside the solidification mold 14a.

[0073] In this case, the high-temperature side of the solidification mold 14a is located near the boundary between the melting portion and the transition portion, as shown in Figure 5(B), and the resin on the high-temperature side can be deformed by the pressure of the solidification mold 14a. The distance between the low-temperature side and the high-temperature side of the solidification mold 14a is preferably 50 mm or more. The distance between the low-temperature side and the high-temperature side depends on the temperature gradient created by the mold, i.e., the mold structure. If the resin is an amorphous resin, it does not have a clear melting point and its elastic modulus changes gradually with temperature changes. Therefore, it is sufficient that the resin is located in the transition portion on the high-temperature side of the solidification mold 14a, and the resin on the high-temperature side can be deformed by the pressure of the solidification mold 14a.

[0074] (Additional Functions of the Solidification Mold 14a) In the conventional example shown in FIG. 5(A), there is a gradient in internal pressure between the center and edges of the upper and lower dies, and the molten zone is fluid, resulting in the FRP material 2 stretching from the center toward the edges during molding. This stretching amount can reach, for example, approximately 1% or more of the molding range. In the present invention shown in FIGS. 5(B) and 5(C), the use of the solidification mold 14a can suppress this stretching phenomenon. Furthermore, for this additional function, the solidification mold 14a may be divided into two sections: one for preventing stretching and one for preventing internal defects. In this case, the solidification mold for stretch prevention may be located away from the heated areas of the mold (the molding zone Za and non-molding zone Zb).

[0075] (Modes in which internal defects occur) In Figure 5(B), if the range of the solidification mold 14a is too wide, the high-temperature side of the solidification mold 14a is located in the molten zone, and the solidification mold 14a is pushed up by thermal expansion of the molten zone, internal defects may occur in the transition zone. Also, if the range of the solidification mold 14a is wide and the temperature of the solidification mold 14a is too low, no part will separate from the mold, but the range that can be molded within the mold will be narrow. Conversely, if the range of the solidification mold 14a is too narrow, the high-temperature side of the solidification mold 14a is located in the low-temperature zone, and the transition zone is located between the upper and lower molds, the situation will be the same as Figure 5(A), and internal defects may occur in the transition zone.

[0076] (Function of thick-walled portion mold 14b) Fig. 6 is a diagram illustrating the function of thick-walled portion mold 14b. Note that this example shows a case where the FRP material 2 and the FRP product 3 have a thin portion 2a that is relatively thin and a thick portion 2b that is thicker than the thin portion 2a.

[0077] Figures 6(A) and 6(B) show a conventional example in which a thick-walled mold 14b is not used, and an FRP material 2 having a thin portion 2a and a thick portion 2b is pressed between an upper mold and a lower mold. Figure 6(A) shows the state in which the molten FRP material 2 is pressed. In this state, the resin has fluidity due to its reduced viscosity, filling the space between the upper and lower molds without any gaps. Figure 6(B) shows the state in which the resin has cooled and solidified from the state shown in Figure 6(A). When the resin cools and solidifies, the amount of shrinkage during solidification is smaller in the thin portion 2a and larger in the thick portion 2b. As a result, sufficient pressure is not applied to the thick portion 2b, which may result in internal defects in the thick portion 2b.

[0078] FIG. 6(C) is a schematic diagram of the state after molding using the thick-walled mold 14b of the present invention. The mold is cooled after the resin has filled the gap between the upper and lower molds, solidifying the FRP material 2 and the FRP product 3. In this case, pressure is applied by the thick-walled mold 14b and the upper and lower molds during cooling. As the resin cools and solidifies, the amount of shrinkage during solidification is smaller in the thin-walled portion 2a and larger in the thick-walled portion 2b. However, because the thick-walled mold 14b is driven independently, sufficient pressure is applied to the thick-walled portion 2b, suppressing or preventing internal defects in the thick-walled portion 2b.

[0079] (Fixing structure of partial fixed mold 15) Figure 7 is an explanatory diagram of the fixing structure of the partial fixed mold 15. The left figure in Figure 7(A) is an external view of the mold body 12, and the right figure is a cross-sectional view taken along line A-A thereof. The left figure in Figure 7(B) is a rear view of the partial fixed mold 15, and the right figure is a cross-sectional view taken along line B-B thereof. Furthermore, the left figure in Figure 7(C) is an external view of the state in which the partial fixed mold 15 is fixed to the mold body 12, and the right figure is a cross-sectional view taken along line C-C thereof.

[0080] In FIG. 7B , the partial fixed mold 15 has a long member 20 extending longitudinally with a constant width B, and a mount portion 22 that can be attached to and detached from the mold body 12 by fitting. The molding outer surface G3 of the partial fixed mold 15 is flat in the illustration, but can have any shape corresponding to the shape of the molding surface of the FRP material 2. The long member 20 has the molding outer surface G3 of the partial fixed mold 15. The mount portion 22 has a single leg portion 23 extending from the long member 20 on the side opposite the molding outer surface G3, and multiple first claw portions 24 protruding from the end of the leg portion 23 on the mold body side on both sides in the width direction of the long member 20. The leg portion 23 is formed integrally with the long member 20, and its width b is set smaller than the width B of the long member 20. The multiple first claw portions 24 are arranged at a constant pitch P in the longitudinal direction of the partial fixed mold 15. In addition, a narrow portion 25 without a first claw portion 24 is provided midway within the pitch P.

[0081] 7A, the mold body 12 has a single groove 26 that fits into the mount portion 22. As shown in the right diagram of FIG. 7A, the groove 26 is shaped to accommodate the leg portion 23 and first claw portion 24 of the partial fixed mold 15. The mold body 12 also has a plurality of second claw portions 27 that fit into the gaps between the elongated member 20 of the partial fixed mold 15 and the first claw portion 24. The second claw portions 27 are arranged at the same pitch P as the first claw portions 24 in the width direction (Y direction) of the mold body 12. A wide portion 28 without a second claw portion 27 is provided midway along the pitch P. Furthermore, the length of the wide portion 28 of the mold body 12 is set longer than the first claw portion 24 of the partial fixed mold 15.

[0082] With the above-described fixing structure, the first claw portion 24 of the partial fixed mold 15 is inserted through the wide portion 28 of the mold body 12, and the back surface of the partial fixed mold 15 is brought into close contact with the outer surface of the mold body 12. Next, by moving the partial fixed mold 15 in the lengthwise direction by half the pitch P, the partial fixed mold 15 can be fitted into the mold body 12, as shown in Fig. 7(C). Note that in Fig. 7(C), it is preferable to fix the end with a retaining plate (not shown) to prevent it from coming off.

[0083] 7(C), the first claw portion 24 and the second claw portion 27 are fitted together, and the dimensions of each portion are set so that in this state the back surface 23a of the leg portion 23 is in close contact with the bottom surface 26a of the recessed groove 26. With this configuration, force and heat can be smoothly transmitted between the partially fixed mold 15 and the mold body 12 via the back surface 23a and the bottom surface 26a.

[0084] (Fixing structure of partially driven mold) Figure 8 is an explanatory diagram of the fixing structure of the thick-walled portion mold 14b. Figure 8(A) is an enlarged view of the thick-walled portion mold 14b in Figure 4, and Figure 8(B) is an outline drawing of one end (the lower end in the figure) of the rod-shaped member 16a. Also, Figure 8(C) is a cross-sectional view taken along CC in Figure 8(A), and Figure 8(D) is a view taken along the arrows D-D in Figure 8(A).

[0085] In Figure 8, the partially driven mold 14 is configured to be detachably attached by fitting onto the lower end of a rod-shaped member 16a. In Figure 8(B), the rod-shaped member 16a has a small-diameter portion smaller than the outer diameter D of the lower end, located between a first distance L1 and a second distance L2 from one end (the lower end in the figure). In Figures 8(C) and 8(D), the thick-walled portion mold 14b has a stepped hole 29 on its back surface into which the lower end of the rod-shaped member 16a can be detachably attached. The stepped hole 29 consists of a first recess 29a into which the lower end of the rod-shaped member 16a can be inserted, and a second recess 29b having a support claw 29c that fits into the small-diameter portion with a diameter d1. The first recess 29a and the second recess 29b are configured to allow the partially driven mold 14 to move in its longitudinal direction relative to the lower end of the rod-shaped member 16a.

[0086] Using the rod-shaped member 16a and thick-walled portion mold 14b described above, the rod-shaped member 16a is moved in the width direction (Y direction) of the mold body 12 with the lower end of the rod-shaped member 16a inserted into the first recess 29a, as shown in the left drawings of Figures 8(C) and (D). This allows the thick-walled portion mold 14b to be fixed to the lower end of the rod-shaped member 16a, as shown in the right drawings of Figures 8(C) and (D). Furthermore, by moving the rod-shaped member 16a in the opposite direction, the thick-walled portion mold 14b can be removed from the lower end of the rod-shaped member 16a.

[0087] The fixing structure of the solidification portion mold 14a is the same as the fixing structure of the thick portion mold 14b. A similar fixing structure may also be applied to the fixing structure of the partial fixing mold 15.

[0088] (Second embodiment of inner mold 10A) Figure 9 is a diagram of a second embodiment of the inner mold 10A (upper mold in this figure), and is an enlarged cross-sectional view of the inner mold 10A of Figure 3. Differences from the first embodiment will be explained below. In this example, the partial driving device 16 includes a piston 11 and a second pressing control device 13. It is preferable to provide a plurality of partial driving devices 16 (preferably three or more) at intervals in the width direction (Y direction) of the mold body 12 relative to the partially driven mold 14.

[0089] The piston 11 is fixed to the partially driven mold 14, fits into a cylindrical cavity 12a provided in the mold body 12, and is movable in the axial direction of the cylindrical cavity 12a. In this example, the piston 11 is integrated with the lower end of the rod-shaped member 16a shown in Figure 8, and a seal member is attached to the outer periphery of the piston 11.

[0090] The mold body 12 has flow paths 12b and 12c that connect the cylindrical cavity 12a to the outside. The second pressing force control device 13 supplies pressure oil to the cylindrical cavity 12a via the flow paths 12b and 12c provided in the mold body 12 to move the piston 11 in the pressing direction and adjust the pressure acting on the molding surface. The second pressing force control device 13 is, for example, a hydraulic unit or a pneumatic unit. The second pressing force control device 13 is installed outside the mold body 12 and is connected to the mold body 12 via piping (not shown). The second pressing force control device 13 may be substantially identical to the first pressing force control device 16c. The other configurations are the same as those of the first embodiment.

[0091] According to the second embodiment of the inner mold 10A described above, by supplying pressure oil from the second pressing control device 13 to each cylindrical cavity 12a, the partially driven mold 14 can be moved in the pressing direction together with the piston 11. In this case, it is preferable to use high-temperature hydraulic oil that can be used at molding temperatures as the pressure oil (hydraulic oil).

[0092] 3 and 9, the outer molding surfaces of the inner mold 10A and the outer mold 10B have a molding zone Za and a non-molding zone Zb. The non-molding zone Zb is divided into a preheating zone and a cooling zone. During molding, the FRP material 2 in the molding zone Za is in a molten state, and the FRP material 2 (or FRP product 3) in the non-molding zone Zb consists of a low-temperature portion and a transition portion.

[0093] 10A is an explanatory diagram of a partial molding repeat method. In this figure, the molding positions of the inner mold 10A and the outer mold 10B are fixed, and the FRP material 2 moves from left to right in the X direction.

[0094] In the first molding, the molding zone Za (the shaded area in the figure) molds the FRP material 2 into an FRP product 3. In the second molding, the rear end of the first molding (the left end in the figure) is positioned and molded in the second molding zone Za. With this configuration, the rear end of the first molding is molded into the FRP product 3, and then heated and molded again, so that the rear end of the first molding and the front end of the second molding can be molded into a seamless FRP product 3. The molding process from the third molding onwards is the same as the second molding.

[0095] As described above, when the entire large FRP material 2 is molded into the FRP product 3 by repeated partial molding, the area that was molded into FRP in the previous round is included in the molding zone Za of the next round. Note that molding may be performed by positioning the rear end of the first round and the front end of the second round so that they come into contact with each other.

[0096] 10B is another explanatory diagram of the partial molding repeat method. As shown in this figure, as a variation, the temperature may be raised in the non-molding zone Zb of the mold to mold the FRP material. For example, this is the case when you want to mold the FRP material all the way to the edge.

[0097] (FRP molding method) Figure 11 is an overall flow diagram of the FRP molding method of the present invention. The FRP molding method of the present invention is a method for molding an FRP material 2 to produce an arc-shaped FRP product 3 with a radius of 1 m or more. The FRP material 2 is made of a single layer of prepreg 1 or a plurality of laminated prepregs 1.

[0098] In this diagram, the FRP molding method includes steps S1 to S8.

[0099] In the material preparation step S1, an FRP material 2 containing a thermoplastic resin is prepared. The FRP material 2 is a material that is made by laminating a plurality of prepregs 1 and becomes an FRP product 3 after molding.

[0100] In the material positioning step S2, the FRP material 2 is positioned relative to the inner mold 10A or the outer mold 10B. During the first molding, the FRP material 2 to be molded first is positioned between the inner mold 10A and the outer mold 10B, and the molded portion of the FRP material 2 is held between the inner mold 10A and the outer mold 10B. At this stage, care is taken to prevent any deforming force from acting on the FRP material 2. The same applies to positioning from the second time onwards. After the material positioning step S2, a step of setting a mandrel and stringers may be included.

[0101] In the temperature raising step S3, the temperature of the inner mold 10A or the outer mold 10B starts to be raised, and by step S5, the temperature of the mold body 12 is raised to a predetermined molding temperature and maintained at that temperature.

[0102] In the solidification section pressurizing step S4, the solidification section mold 14a is pressed and held against the FRP material 2 in the non-molding zone Zb. At this time, it is preferable that the mold body 12 of the inner surface mold 10A or the outer surface mold 10B remains stationary, and the solidification section mold 14a is pressed by the partial drive device 16 and the pressure is maintained.

[0103] In the molding section pressurizing step S5, the mold body 12 and the thick section mold 14b are pressed and held against the FRP material 2 in the molding zone Za. At this time, the pressure exerted by the mold body 12 and the thick section mold 14b, along with the solidification section mold 14a, are independently controlled and maintained. The pressure during molding (molding pressure) is, for example, 1 to 10 MPa.

[0104] The solidified portion pressurizing step S4 and the molded portion pressurizing step S5 may be performed simultaneously, or may be performed at the same time as step S5 or may be performed first.

[0105] In the temperature holding step S6, the molding temperature is held for a predetermined time. The holding time for the molding temperature is, for example, 5 to 60 minutes. In the cooling step S7, the mold is cooled by a cooling device. Cooling is performed, for example, by flowing cooling air into the mold.

[0106] After the mold is cooled and the entire FRP product 3 is solidified, the mold is opened and the process returns to step S2. Steps S2 to S7 are repeatedly executed until the entire FRP material 2 is converted into FRP to form the FRP product 3.

[0107] After the entire FRP material 2 has been converted into FRP to form the FRP product 3, in step S8, the mold is opened and the FRP product 3 is taken out.

[0108] The FRP molding method using the partial pressing device 30 shown in Figure 3 includes a partial pressing step and a conveying step, which are repeated. The partial pressing step corresponds to steps S3 to S7. That is, in the partial pressing step, a portion of the FRP material 2 is heated under pressure using the FRP molding die 10 to reduce the viscosity of the resin and impregnate the fibers with the resin to form FRP. The conveying step corresponds to step S2, in which the portion of the FRP material 2 formed in the partial pressing step is moved intermittently. By repeating the partial pressing step and the conveying step, a large FRP product 3 can be made.

[0109] According to the above-described embodiment of the present invention, the FRP molding die 10 includes a partial drive device 16 capable of driving the partially driven die 14 independently of the die body 12, and a heating device 18 capable of heating the die body 12. With this configuration, even if the specific volume (e.g., thickness) of the FRP material 2 or FRP product 3 increases due to thermal expansion in the heating section (e.g., molding zone Za) heated by the heating device 18, the outer molding surface of the partially driven die 14 can be driven independently of the die body 12. This allows sufficient pressure to be applied to the entire molding surface of the FRP material 2 during the process of converting the FRP material 2 into FRP, preventing or suppressing the occurrence of internal defects and enabling the molding of an FRP product with few internal defects.

[0110] In particular, the use of the solidification portion mold 14a can prevent out-of-plane meandering of the layers and expansion of microvoids, while the use of the thick portion mold 14b can suppress or prevent the occurrence of internal defects in the thick portion.

[0111] Furthermore, according to an embodiment of the present invention, in the solidification section pressurizing step S4, the solidification section mold 14a is pressed toward and held against the FRP material 2 in the non-molding zone Zb. Then, in the subsequent molding section pressurizing step S5, the mold body 12 and thick section mold 14b, together with the solidification section mold 14a, are pressed toward and held against the FRP material 2 in the molding zone Za. This method makes it possible to prevent the FRP material 2 from stretching from the center toward the edges during molding.

[0112] Furthermore, according to an embodiment of the present invention, the steps from the material positioning step S2 to the cooling step S7 are repeatedly performed until the entire FRP material 2 is converted into FRP to form the FRP product 3. This allows for the molding and manufacturing of an arc-shaped FRP product 3 (e.g., a large FRP product with a radius of 1 m or more) having components 6 (e.g., stringers) using a small mold.

[0113] Furthermore, according to an embodiment of the present invention, when the entire large FRP material 2 is molded into an FRP product 3 by repeated partial molding, the area that was converted into FRP in the previous round is brought into contact with the molding zone Za of the next round, so that the entire FRP material 2 can be molded into the FRP product 3. Furthermore, by including the area that was converted into FRP in the previous round in the molding zone Za of the next round, the entire FRP material 2 can be molded into the FRP product 3.

[0114] In the above example, the FRP product 3 is arc-shaped, but the present invention can also be applied to FRP products such as stringers that have a planar shape stretched in one axial direction (for example, FRP products with a Z-shaped, L-shaped, or hat-shaped cross section).

[0115] The present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made without departing from the spirit of the present invention.

[0116] D: outer diameter, F1: inner arc surface, F2: inner groove, F3: outer arc surface, G, G1, G2, G3: molded outer surface, L1: first distance, L2: second distance, P: pitch, X: FRP material movement direction, Y: width direction, Za: molding zone, Zb: non-molding zone, 1: prepreg, 2: FRP material, 2a: thin-walled portion, 2b: thick-walled portion, 3: FRP product, 5: arc portion, 6: member (stringer), 7a: upper surface, 7b: side surface, 7c: leg portion, 8: mandrel, 8a: upper surface, 8b: inclined surface, 8c: bottom surface, 10: FRP molding mold, 10A: inner mold, 10B: outer mold, 11: piston, 12: mold body, 12a: cylindrical cavity, 12b, 12c: flow path, 13: second pressing control device, 14 Partially driven mold, 14a solidification portion mold, 14b thick portion mold, 15 partially fixed mold, 16 partially driven device, 16a rod-shaped member, 16b linear motion device, 16c first pressing control device, 17a, 17b direction change member, 18 heating device, 19 cooling device, 20 long member, 22 mount portion, 23 leg portion, 23a back surface, 24 first claw portion, 25 narrow portion, 26 recessed groove, 26a bottom surface, 27 second claw portion, 28 wide portion, 29 stepped hole, 29a first recess, 29b second recess, 29c support claw, 30 partial pressing device, 31 bolster, 32 slide, 33 hydraulic ram, 34 press frame, 40 conveying device, 42 gripping device, 44 moving device, 100 FRP molding system

Claims

1. An FRP molding die for heating an FRP material containing resin under pressure to convert it into FRP, comprising an inner die and an outer die which hold the FRP material therebetween, the inner die or the outer die comprising: a die body; a partial drive die attached to the die body and movable in a pressing direction which applies pressure to the molding surface of the FRP material; a partial drive device capable of driving the partial drive die independently of the die body; and a heating device capable of heating the die body.

2. The FRP molding die as described in claim 1, wherein the partial drive device comprises: a rod-shaped member having one end fixed to the partial drive die and extending in the opposite direction to the pressing direction; a linear motion device fixed to the die body for moving the other end of the rod-shaped member in the pressing direction; and a first pressing control device for controlling the linear motion device to adjust the pressure acting on the molding surface.

3. The FRP molding die as described in claim 1, wherein the partial drive device comprises: a piston fixed to the partial drive die, fitted into a cylindrical cavity provided in the die body, and movable in the axial direction of the cylindrical cavity; and a second pressing control device which supplies pressurized oil to the cylindrical cavity via a flow path provided in the die body to move the piston in the pressing direction and adjust the pressure acting on the molding surface.

4. An FRP molding mold as described in claim 1, wherein the inner mold and the outer mold have molding outer surfaces that abut against the molding surface of the FRP material, and the molding outer surfaces have a molding zone that converts the FRP material at the abutting portion into FRP, and a non-molding zone that is adjacent to and located outside the molding zone and that preheats or cools the FRP material.

5. The FRP molding mold according to claim 4, wherein the partially driven mold is a solidification section mold located in the non-molding zone, and the temperature of the molding outer surface of the solidification section mold is maintained at a temperature gradient of -0°C to -300°C on the low temperature side and +0°C to +110°C on the high temperature side relative to the melting point of the resin.

6. The FRP molding die according to claim 4, wherein the FRP material has a relatively thin portion and a thick portion that is thicker than the thin portion, and the partially driven die is a thick portion die that is located in the molding zone and abuts against the thick portion.

7. An FRP molding mold as described in claim 4, having a partial fixed mold removably attached to the mold body in the molding zone, the partial fixed mold having a long member having a constant width and extending in the length direction, and a mounting portion that can be attached and detached by fitting into the mold body.

8. An FRP molding die as described in claim 7, wherein the long member has the molded outer surface of the partial fixed die, the mounting portion has a single leg extending from the long member to the side opposite the molded outer surface, and a plurality of first claw portions protruding from an end of the leg on the die body side on both sides in the width direction of the long member, the plurality of first claw portions being arranged at a constant pitch in the length direction of the partial fixed die, and a narrow portion without the first claw portions being provided intermediate the pitch, the die body having a single groove that engages with the mounting portion and accommodates the leg and the first claw portions, and a plurality of second claw portions that engage with gaps between the long member and the first claw portions, the plurality of second claw portions being arranged at the same pitch as the first claw portions in the width direction of the die body, and a wide portion without the second claw portions being provided intermediate the pitch, and the wide portion is set to be longer than the first claw portions.

9. The FRP molding die according to claim 2, wherein the partially driven die is configured to be detachable by fitting onto the lower end of the rod-shaped member.

10. An FRP molding die as described in claim 9, wherein the rod-shaped member has a small diameter portion smaller than the outer diameter of the lower end portion between a first distance and a second distance from the one end, the partial driving die has a stepped hole on its back surface into which the lower end portion of the rod-shaped member can be attached and detached, the stepped hole consisting of a first recess into which the lower end portion of the rod-shaped member can be inserted and a second recess having a support claw that fits into the small diameter portion, and the first recess and the second recess are configured to allow the partial driving die to be moved in its longitudinal direction relative to the lower end portion of the rod-shaped member.

11. An FRP molding system comprising: a partial pressing device having a bolster and a slide for fixing the FRP molding die described in claim 1, and for intermittently compressing a portion of the FRP material to partially mold the FRP material; and a transport device for intermittently moving the portion of the FRP material compressed by the partial pressing device.

12. An FRP molding method comprising: gripping the FRP material between the inner mold and the outer mold of the FRP molding mold described in claim 1; driving the mold body and the partially driven mold independently of each other to pressurize the FRP material; and heating the FRP material under pressure to convert it into FRP.

13. An FRP molding method as described in claim 12, comprising: a material positioning step for positioning the FRP material relative to the inner surface mold or the outer surface mold; a heating step for heating the mold body to a predetermined molding temperature and maintaining it thereat; a solidification section pressurizing step for pressurizing the solidification section mold toward the FRP material and maintaining it thereat; a molding section pressurizing step for independently controlling the pressures exerted by the mold body and the partially driven mold and for pressurizing the mold body and the partially driven mold toward the FRP material and maintaining it thereat; a temperature maintaining step for maintaining the molding temperature for a predetermined period of time; and a cooling step for cooling the mold body.

14. The FRP molding method according to claim 13, further comprising a step of setting a mandrel and a stringer after the material positioning step.

15. An FRP molding method as described in claim 12, wherein the resin is a thermoplastic resin, the method comprising: a partial pressing step in which a portion of the FRP material is heated under pressure using the FRP molding die to reduce the viscosity of the resin and impregnate the fibers with the resin to form an FRP; and a transport step in which the molded portion of the FRP material formed by the partial pressing step is intermittently moved, and the partial pressing step and the transport step are repeated.

16. The FRP molding method described in claim 15, wherein the inner mold and the outer mold have molding outer surfaces that abut against the molding surface of the FRP material, and the molding outer surfaces have a molding zone that converts the FRP material in the abutting portion into FRP, and a non-molding zone that is adjacent to and located outside the molding zone and that preheats or cools the FRP material.

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