Manufacturing method of composite molding

Abstract

To provide a method for manufacturing composite molded bodies that can improve the shape accuracy of joined parts of two composite molded bodies.SOLUTION: In a method for manufacturing composite molded bodies according to the present disclosure, first and second composite materials W1 and W2 are respectively molded to form first and second composite molded bodies M1 and M2. The first and second composite molded bodies M1 and M2 include joined parts M1b and M2b that can be joined to each other. The joined parts M1b and M2b are joined together to form a composite material joined body. The first and second composite materials W1 and W2 include to-be-joined parts W1b and W2b corresponding to the joined parts M1b and M2b of the first and second composite molded bodies M1 and M2, respectively. The method includes: a step ST11 of arranging a mandrel 3 and a pressing part in a space sandwiched between the first and second composite materials W1 and W2 arranged in a mold 10; and a step ST12 in which the pressing part presses the mandrel 3 against the to-be-joined part W2b of the second composite material W2.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present disclosure relates to a method for manufacturing a composite molded body, and to a method for manufacturing two composite molded bodies that can be joined together to form a composite joint. [Background technology]

[0002] In the manufacturing method disclosed in Patent Document 1, a wind turbine blade made of a fiber-reinforced resin hollow part is integrally molded using a low-melting-point alloy core. In the manufacturing methods disclosed in Patent Documents 2 and 3, two half-split molds corresponding to the shape of half of the blade are used. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2017 / 126287 [Patent Document 2] JP 2011-137386 A [Patent Document 3] JP 2012-082832 A Summary of the Invention [Problem to be solved by the invention]

[0004] The present inventors have discovered the following problems. The technology disclosed in Patent Document 1 is a molding method (RTM: Resin Transfer Molding) in which a reinforcing fiber substrate that has not been impregnated with resin beforehand is impregnated with liquid resin later. In the technology disclosed in Patent Document 1, when the same reinforcing fibers are used, it is necessary to impregnate a dense reinforcing fiber layer with liquid resin in a short time, compared to a molding method in which pressure is applied to a prepreg substrate that has been impregnated with resin beforehand. As a result, the manufacturing method disclosed in Patent Document 1 has inferior material properties compared to the molding method, for the reasons that (1) high-performance resins with high viscosity cannot be used, and (2) resin does not impregnate at high fiber content. Therefore, in order to obtain the same product strength, a design such as increasing the thickness is required, which has the disadvantage of increasing the mass. In addition, there is a problem that a core using a low melting point alloy requires additional processes such as manufacturing and elution of the core. Furthermore, since the specific gravity of a low melting point alloy is heavier than that of iron, it takes time for the temperature of the low melting point alloy core to rise when the resin hardens, and the transport device is also large.

[0005] Patent Document 2 does not specify the material to be molded or the molding method, but when the manufacturing method disclosed in Patent Document 2 is RTM, it has the same problems as the manufacturing method disclosed in Patent Document 1. Also, when molding with a half-split mold using a prepreg material, an autoclave is required to apply pressure to the material, but molding using an autoclave has problems such as high equipment costs for the autoclave and long molding times due to temperature control (heating and cooling) by the atmospheric temperature.

[0006] Although Patent Document 3 does not specify the material to be molded, when the manufacturing method disclosed in Patent Document 3 is RTM, it has the same problems as the technology disclosed in Patent Document 1. When a prepreg material is used, the manufacturing method disclosed in Patent Document 3 allows pressure to be applied by an internal bag. However, since the shape and position of the web part cannot be maintained, the web cannot be maintained with high precision every time it is mass-produced. In addition, the reinforcing fibers of the web, which bear the important strength and rigidity, are not continuous. For these reasons, there are problems in applying it to aircraft that require high reliability and large wind turbines that require strength.

[0007] The present disclosure has been made in consideration of the above-mentioned problems, and provides a manufacturing method for a composite molded body that can improve the shape accuracy of the joined portions of two composite molded bodies. [Means for solving the problem]

[0008] The method for producing a composite molded body according to the present disclosure includes: A method for manufacturing a composite molded body, comprising molding a first composite material and a second composite material to form a first composite molded body and a second composite molded body, respectively, comprising the steps of: The first and second composite molded bodies each have a joinable portion that can be joined to each other, the joined portions of the first and second composite molded bodies are joined to each other to form a composite joint body; the first and second composite materials each have a portion to be joined corresponding to a portion to be joined of the first and second composite molded bodies, A step of arranging a mandrel and a pressing part in a space sandwiched between first and second composite materials arranged in a molding die, the mandrel being sandwiched between the pressing part and the portions to be joined of the first and second composite materials; The method includes a step in which the pressing portion presses the mandrel against the portion to be joined of the second composite material.

[0009] The molding die may be provided with a means for controlling the temperature of the die using a heat medium (water, oil, gas, etc.) or electricity (heater, induction heating, dielectric heating, etc.).

[0010] The composite molding can be produced by either a prepreg sheet that has already been impregnated with semi-cured resin, or a method in which a reinforcing fiber sheet that has not been impregnated with resin is filled with liquid resin in a mold and impregnated with the resin. By combining the composite molding with a prepreg sheet that has excellent material properties, a product with excellent weight reduction can be obtained.

[0011] According to this configuration, the pressing portion presses the mandrel against the portion to be joined of the second composite material to mold the second composite material and form the second composite molded body. This makes it possible to form the portion to be joined of the second composite molded body with high shape accuracy. Therefore, it is possible to improve the shape accuracy between the portions to be joined of the first and second composite molded bodies.

[0012] In addition, in the process in which the pressing unit presses the mandrel against the portion of the second composite material to be joined, the pressing unit may be provided with an inflatable first bag, and may pressurize the first bag by supplying gas into the first bag or by expanding the first bag, thereby pressing the mandrel against the portion of the second composite material to be joined.

[0013] According to this configuration, the first bag can expand and press against the second composite material of various shapes, etc. Therefore, it is possible to mold the second composite material of various shapes and form the joining portion of the second composite molded body with high shape accuracy.

[0014] In addition, the first bag may have an end inserted between the portions of the first and second composite materials to be joined, and gas may be supplied into the first bag to pressurize the inside of the first bag or the first bag may be expanded, causing the end of the first bag to press the portions of the first composite materials to be joined against the molding die.

[0015] According to this configuration, the end of the first bag presses the portion to be joined of the first composite material against the molding die to form the first composite molded body, thereby making it possible to form the portion to be joined of the first composite molded body with high shape accuracy.

[0016] In addition, in the step of the pressing unit pressing the mandrel against the portion to be joined of the second composite material, the pressing unit may further include a second bag disposed in the first bag, and may supply gas into the second bag to inflate the second bag. Also, the pressure P2 in the second bag may be greater than the pressure P1 in the first bag.

[0017] According to this configuration, the force with which the mandrel presses against the to-be-joined portion of the second composite material can be increased by inflating the second bag, thereby improving the shape accuracy of the to-be-joined portion of the second composite molded body.

[0018] In addition, in the process in which the pressing unit presses the mandrel against the portion of the second composite material to be joined, the pressing unit may include a thermal expansion body disposed in the first bag, and may heat the thermal expansion body to cause it to thermally expand.

[0019] According to this configuration, it is possible to improve the shape accuracy of the joined portion of the second composite molded body by using a thermally expandable body having a simple configuration.

[0020] With this configuration, pressure can be applied to the composite material in the pressing section and the temperature of the molding die can be controlled in a short period of time, without using an autoclave, which is generally expensive and requires time-consuming temperature control, when molding high-quality composite products using prepreg sheets. This makes it possible to produce high-quality composite molded products with high productivity.

[0021] The composite joint is a wing or a propeller of an aircraft, In the composite joint, the joined portions of the first and second composite molded bodies may be leading edges of the wings or propellers of the aircraft.

[0022] With this configuration, the leading edge of an aircraft wing or a propeller can be formed with high shape precision. Effect of the Invention

[0023] According to the present disclosure, it is possible to improve the shape precision between the portions to be joined of two composite molded bodies. [Brief description of the drawings]

[0024] [Figure 1] 4 is a flowchart showing a method for manufacturing a composite molded body according to the first embodiment. [Diagram 2] 3 is a schematic diagram showing an upper die in a step of the method for producing a composite molded body according to the first embodiment. FIG. [Diagram 3] 3 is a schematic view showing a cross section of an upper die in a step of the method for producing a composite molded body according to the first embodiment. FIG. [Figure 4] 3 is a schematic diagram showing a lower die in a step of the method for producing a composite molded body according to the first embodiment. FIG. [Diagram 5] 3 is a schematic view showing a cross section of a lower die in a step of the method for producing a composite molded body according to the first embodiment. FIG. [Figure 6] 2 is a schematic diagram showing one step of a method for producing a composite molded body according to the first embodiment. FIG. [Figure 7] FIG. 2 is a schematic diagram showing a composite molded body. [Figure 8] 10 is a flowchart showing a method for manufacturing a composite molded body according to the second embodiment. [Figure 9] 10 is a schematic view showing a lower die in a step of a method for producing a composite molded body according to embodiment 2. FIG. [Figure 10] 10 is a schematic view showing a cross section of a lower die in a step of a method for producing a composite molded body according to embodiment 2. FIG. [Figure 11] 10 is a schematic diagram showing one step of a method for producing a composite molded body according to the second embodiment. FIG. [Figure 12] 3 is a schematic diagram showing a specific example of a step of the method for producing a composite molded body according to the first embodiment. FIG. [Figure 13] 10 is a schematic diagram showing a specific example of a step of a method for producing a composite molded body according to the second embodiment. FIG. [Figure 14]11 is a flowchart showing a method for manufacturing a composite molded body according to the third embodiment. [Figure 15] 13 is a schematic view showing a lower die in a step of a method for producing a composite molded body according to embodiment 3. FIG. [Figure 16] 13 is a schematic view showing a cross section of a lower die in a step of a method for producing a composite molded body according to embodiment 3. FIG. [Figure 17] FIG. 11 is a schematic diagram showing one step of a method for producing a composite molded body according to the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings. However, the present invention is not limited to the following embodiments. In addition, the following description and drawings are appropriately simplified for clarity of explanation.

[0026] (Embodiment 1) A method for producing a composite molded body according to the first embodiment will be described with reference to Figs. 1 to 7. The method for producing a composite molded body according to the present embodiment uses a prepreg sheet, but it is also applicable to a method in which a reinforcing fiber sheet is filled and impregnated with a liquid resin in a mold without using a prepreg sheet. The method for producing a composite molded body according to the present embodiment can be carried out without using an autoclave. Fig. 1 is a flow chart showing a method for producing a composite molded body according to the first embodiment. Fig. 2 is a schematic diagram showing an upper mold in one step of the method for producing a composite molded body according to the first embodiment. Fig. 3 is a schematic diagram showing a cross section of the upper mold shown in Fig. 2. Fig. 4 is a schematic diagram showing a lower mold in one step of the method for producing a composite molded body according to the first embodiment. Fig. 5 is a schematic diagram showing a cross section of the lower mold shown in Fig. 4. Fig. 6 is a schematic diagram showing one step of the method for producing a composite molded body according to the first embodiment. Fig. 7 is a schematic diagram showing a composite molded body.

[0027] Naturally, the right-handed xyz coordinate system shown in FIG. 2 and other drawings is for the convenience of explaining the positional relationship of the components. Usually, the z-axis positive direction is vertically upward, and the xy plane is a horizontal plane, which is common to all drawings. For ease of viewing, in FIG. 2 and FIG. 3, unlike the other drawings, the upper mold 1 described later and the like are inverted upside down. For ease of viewing, the hatching of the upper mold body 1a and the lower mold body 2a described later are omitted. The upper film 4a, the lower film 4b, and the first bag 4 described later are illustrated generally using dashed lines.

[0028] The manufacturing method of the composite molded body according to the present embodiment can be carried out, for example, by using a molding die 10 shown in FIG. 6. In the manufacturing method of the composite molded body according to the present embodiment, the first and second composite materials W1 and W2 are molded, respectively, to manufacture the first and second composite molded bodies M1 and M2 shown in FIG. 7. The first composite molded body M1 includes a main body M1a and a joining portion M1b. The joining portion M1b extends from one end of the main body M1a. The second composite molded body M2 includes a main body M2a and a joining portion M2b. The joining portion M1b extends from one end of the main body M1a. The joining portions M1b and M2b can be joined to each other. When the joining portions M1b and M2b are joined to each other, a composite joined body is formed.

[0029] The molding die 10 includes an upper die 1 and a lower die 2. The upper die 1 is disposed above the lower die 2. The upper die 1 and the lower die 2 are held so that they can be pressed against each other or separated from each other.

[0030] As shown in FIG. 2 and FIG. 3, the upper mold 1 includes an upper mold body 1a, a temperature control circuit 1b, and a seal 1c. The upper mold body 1a has a cavity surface 1d, and the cavity surface 1d has a surface shape following the first composite molding M1. The temperature control circuit 1b is provided inside the upper mold body 1a. A temperature controller (not shown) causes a heat medium to flow into, discharge, or circulate the temperature control circuit 1b. The heat medium is, for example, water, oil, or gas. The heat medium provides heat to the upper mold body 1a, and the temperature of the upper mold 1 reaches a predetermined range and is then maintained. The seal 1c surrounds the cavity surface 1d of the upper mold body 1a. The upper mold 1 may have a pipe (not shown). One end of the pipe opens around the cavity surface 1d, and the other end of the pipe is connected to a vacuum pump.

[0031] As shown in FIG. 4 and FIG. 5, the lower mold 2 includes a lower mold body 2a, a temperature control circuit 2b, and a seal 2c. The lower mold body 2a has a cavity surface 2d, and the cavity surface 2d has a surface shape that conforms to the molded body obtained by molding the second composite molded body M2. The temperature control circuit 2b is provided inside the lower mold body 2a. A temperature controller (not shown) causes a heat medium to flow into, discharge, or circulate the temperature control circuit 2b. The heat medium provides heat to the lower mold body 2a, and the temperature of the lower mold 2 falls within a predetermined range. The seal 2c surrounds the cavity surface 2d of the lower mold body 2a. The lower mold 2 may have a pipe (not shown). One end of the pipe opens around the cavity surface 2d, and the other end of the pipe is connected to a vacuum pump. The molding die 10 may be provided with a means for controlling the temperature of the lower die 2 and the lower die 1 electrically, such as a heater, induction heating, or dielectric heating.

[0032] 6, a mandrel 3 and a first bag 4 are placed in a space C1 between the first and second composite materials W1, W2 placed in a molding die 10 (step ST11). The mandrel 3 is sandwiched between the first bag 4 and the portions to be joined W1b, W2b of the first and second composite materials W1, W2. In the method for producing a composite molded product according to this embodiment, the first bag 4 functions as a pressing part that presses the mandrel 3.

[0033] The first bag 4 includes an upper film 4a, a lower film 4b, and an end portion 4c. The end portion 4c is inserted between the portions to be joined W1b, W2b of the first and second composite materials. When gas is supplied into the first bag 4, the first bag 4 expands. A wide variety of gases, for example, air, can be used as the gas. The first bag 4 may be connected to a gas supply source such as a compressor through a pipe (not shown). A valve is provided in the pipe. By opening and closing the valve, gas can be supplied from the gas supply source through the pipe to the first bag 4. When gas is not supplied, the first bag 4 has a shape following the inner wall surfaces of the first and second composite materials W1, W2 because the cavity is evacuated.

[0034] The first and second composite materials W1 and W2 are, for example, general prepregs, in which the fibers are impregnated with resin. The fibers are configured as a braid, woven fabric, or knit fabric of carbon fibers, aramid fibers, nylon fibers, polyester fibers, glass fibers, or any combination thereof. The resin includes a thermosetting resin, such as an epoxy resin, a bismaleimide resin, a vinyl ester resin, an unsaturated polyester resin, a phenolic resin, or a silicone resin.

[0035] Specifically, in step ST11, first, as shown in FIG. 2 and FIG. 3, the first composite material W1 is placed on the cavity surface 1d of the upper mold 1. The first composite material W1 includes a main body W1a and a portion to be joined W1b. The portion to be joined W1b extends from one end of the main body W1a. It is preferable that the portion to be joined W1b is thinner than the main body W1a. The main body W1a and the portion to be joined W1b correspond to the main body M1a and the portion to be joined M1b of the first composite molded body M1 shown in FIG. 7, respectively.

[0036] Subsequently, the upper film 4a is attached onto the first composite material W1. The attachment of the upper film 4a onto the first composite material W1 can be performed, for example, by using the above-mentioned vacuum pump to exhaust the air between the upper film 4a and the first composite material W1 through the above-mentioned piping of the upper mold 1. The upper film 4a may also be attached onto the upper mold 1 around the periphery of the first composite material W1.

[0037] Next, as shown in Figs. 4 and 5, the second composite material W2 is placed on the cavity surface 2d of the lower mold 2. The second composite material W2 includes a main body W2a and a portion to be joined W2b. The portion to be joined W2b extends from one end of the main body W2a. The portion to be joined W2b is preferably thinner than the main body W2a. The main body W2a and the portion to be joined W2b correspond to the main body M2a and the portion to be joined M2b of the second composite molded body M2 shown in Fig. 7, respectively.

[0038] Next, the mandrel 3 is placed on the second composite material W2, specifically, on a portion of the lower mold body 2a including the portion to be joined W2b, which will be an undercut. The mandrel 3 has a surface shape conforming to the second composite molded body M2. The mandrel 3 has a predetermined elastic modulus or hardness. The mandrel 3 is, for example, a rod-shaped body extending along the Y axis. The mandrel 3 may have a hardness higher than that of the first bag 4. The mandrel 3 according to this embodiment is made of aluminum or an aluminum alloy, but the mandrel 3 may be made of another material, for example, a silicone resin.

[0039] Subsequently, the lower film 4b is attached to the second composite material W2 and the mandrel 3. This attachment may be performed, for example, by using the above-mentioned vacuum pump to evacuate the air between the lower film 4b and the second composite material W2 and between the lower film 4b and the mandrel 3 through the above-mentioned piping of the lower mold 2.

[0040] Next, the upper mold 1 and the lower mold 2 are pressed together so that the cavity surface 1d and the cavity surface 2d face each other. In other words, the upper mold 1 and the lower mold 2 are clamped together. Then, the upper film 4a and the lower film 4b are bonded together to form the first bag 4. At this time, the upper mold 1 and the lower mold 2 are clamped and held with the necessary force by a clamping device such as a press (not shown) or bolts so that the upper mold 1 and the lower mold 2 do not open when pressure is applied to the first bag 4 later.

[0041] Next, the first bag 4 is inflated to press the mandrel 3 against the parts to be joined W2b (step ST12).

[0042] Specifically, gas is supplied to the inside of the first bag 4 and pressurized. Then, the first bag 4 expands and pressurizes the mandrel 3 toward the part to be joined W2b (here, in the negative direction of the X-axis). When the first bag 4 is in close contact with the normal shape of the cavity in a vacuum state, the first bag 4 hardly expands in shape even if gas is supplied to the inside of the first bag 4 and the inside of the first bag 4 is pressurized, but the mandrel 3 is pressed toward the part to be joined W2b (here, in the negative direction of the X-axis). As a result, the mandrel 3 presses against the part to be joined W2b. Also, the end 4c of the first bag 4 expands and presses against the parts to be joined W1b and W2b. The end 4c of the first bag 4 presses the part to be joined W1b against the cavity surface 1d of the upper mold 1 to form it. The to-be-joined portion W2b is molded by being sandwiched between the end 4c of the first bag 4 and the mandrel 3. The pressure to which the to-be-joined portions W1b and W2b are subjected from the mandrel 3 and the first bag 4 may be equivalent to the pressure to which the composite material is subjected when a composite material is molded using a general autoclave. The first and second composite materials W1 and W2 are heated and hardened using a temperature regulator. More specifically, the to-be-joined portion W2b is heated while being pressed by the mandrel 3, so that the resin contained in the to-be-joined portion W2b is hardened. The to-be-joined portion W1b is heated while being pressed by the end 4c of the first bag 4, so that the resin contained in the to-be-joined portion W1b is hardened. As a result, the first composite molded body M1 and the second composite molded body M2 shown in FIG. 7 are formed.

[0043] The resin contained in the portions to be joined W1b and W2b may be set as appropriate. The resin contained in the portions to be joined W1b and W2b may be cured until it is in a semi-cured state. Here, the semi-cured state refers to a state in which functional groups remain on the surfaces of the first composite molding M1 and the second composite molding M2, and for example, the degree of curing of the resin of the first composite molding M1 and the resin of the second composite molding M2 is about 60 to 80% (preferably 70%).

[0044] However, the degree of cure of the resin of the first composite molding M1 and the second composite molding M2 can be appropriately set in consideration of the resin of the first composite molding M1 and the resin of the second composite molding M2, the degree of wrinkles of the first composite molding M1 and the second composite molding M2, etc. The degree of cure can be measured based on a heat flow curve obtained by, for example, differential scanning calorimetry (DSC).

[0045] As described above, the first composite material W1 and the second composite material W2 can be molded to produce the first and second composite molded bodies M1, M2, respectively.

[0046] According to the manufacturing method of the composite molded body of this embodiment, the first bag 4 presses the mandrel 3 against the to-be-joined portion W2b of the second composite material W2 to manufacture the second composite molded body M2. The to-be-joined portion M2b of the second composite molded body M2 has high shape accuracy. Therefore, it is possible to improve the shape accuracy of the to-be-joined portions M1b, M2b of the first and second composite molded bodies M1, M2. In addition, the first and second composite molded bodies M1, M2 are molded by applying a pressure equivalent to that of an autoclave without using an autoclave, and it is possible to improve the shape accuracy of the to-be-joined portions M1b, M2b of the first and second composite molded bodies M1, M2.

[0047] Furthermore, the first bag 4 expands to press the mandrel 3 against the to-be-joined portion W2b of the second composite material W2 having various shapes. Therefore, the second composite material W2 having various shapes can be molded, and the to-be-joined portion M2b of the second composite molded body M2 having high shape accuracy can be formed.

[0048] Furthermore, the end 4c of the first bag 4 expands and presses the to-be-joined portion W1b of the first composite material W1 against the cavity surface 1d of the upper die 1. This makes it possible to form the to-be-joined portion M1b of the first composite molded body M1 with high shape accuracy.

[0049] (Embodiment 2) The method for producing a composite molded body according to the second embodiment will be described with reference to Figs. 8 to 11. Fig. 8 is a flow chart showing the method for producing a composite molded body according to the second embodiment. Fig. 9 is a schematic diagram showing a lower die in one step of the method for producing a composite molded body according to the second embodiment. Fig. 10 is a schematic diagram showing a cross section of the lower die shown in Fig. 9. Fig. 11 is a schematic diagram showing one step of the method for producing a composite molded body according to the second embodiment.

[0050] The method for producing a composite molded body according to this embodiment can be carried out, for example, by using a molding die 20 shown in FIG.

[0051] The mold 20 has the same configuration as the mold 10 shown in FIG. 6, except that it includes the second bag 5. The second bag 5 is disposed inside the first bag 4. When gas is supplied into the second bag 5, the second bag 5 expands in the same manner as the first bag 4. The second bag 5 is connected to a gas supply source such as a compressor through a pipe (not shown). The pipe is provided with a valve. By opening and closing the valve, gas is supplied from the gas supply source through the pipe to the second bag 5. The second bag 5 may have a shape that follows the inner wall surface of the first bag 4 when gas is not supplied.

[0052] 11, a mandrel 3, a first bag 4, and a second bag 5 are placed in a space C1 between the first and second composite materials W1, W2 placed in a molding die 20 (step ST21). The mandrel 3 thus placed is sandwiched between the first bag 4 and the portions to be joined W1b, W2b of the first and second composite materials W1, W2. In the method for producing a composite molded product according to this embodiment, the first bag 4 and the second bag 5 function as a pressing part for pressing the mandrel 3.

[0053] Specifically, first, similarly to step ST11 shown in Fig. 1, each component is placed in the upper mold 1. That is, as shown in Fig. 2 and Fig. 3, the first composite material W1 is placed on the cavity surface 1d of the upper mold 1. Then, the upper film 4a is attached onto the first composite material W1.

[0054] 9 and 10, the second composite material W2 is placed on the cavity surface 2d of the lower die 2. Then, the mandrel 3 is placed on the second composite material W2, specifically, on a portion including the portion to be joined W2b. Then, the lower film 4b is attached to the second composite material W2 and the mandrel 3.

[0055] Next, the second bag 5 is placed on the lower film 4b. The mandrel 3 is sandwiched between the second bag 5 and the portion to be joined W2b of the second composite material W2.

[0056] Next, the upper mold 1 and the lower mold 2 are pressed together so that the cavity surface 1d and the cavity surface 2d face each other. In other words, the upper mold 1 and the lower mold 2 are clamped together. Then, the upper film 4a and the lower film 4b are bonded together to form the first bag 4. At this time, the upper mold 1 and the lower mold 2 are clamped and held with the necessary force by a clamping device such as a press (not shown) or bolts so that the molds do not open when pressure is applied to the first bag 4 and the second bag 5 later.

[0057] Next, the first bag 4 and the second bag 5 are inflated to press the mandrel 3 against the parts to be joined W2b (step ST22).

[0058] Specifically, gas is supplied to the inside of the first bag 4 to pressurize it. Furthermore, gas is supplied to the inside of the second bag 5 to pressurize it. It is preferable that the pressurization to the inside of the first bag 4 and the pressurization to the inside of the second bag 5 are performed approximately simultaneously. It is also preferable that the pressure P2 in the second bag 5 is larger than the pressure P1 in the first bag 4. Then, the first bag 4 and the second bag 5 expand and pressurize the mandrel 3 toward the part to be joined W2b (here, in the negative direction of the X-axis). As a result, the mandrel 3 presses against the part to be joined W2b. In addition, the first and second composite materials W1 and W2 are heated using a temperature regulator. More specifically, the part to be joined W2b is heated while being pressed by the mandrel 3, so that the resin contained in the part to be joined W2b is cured. Moreover, the resin contained in the to-be-joined portion W1b is cured because the to-be-joined portion W1b is heated while being pressed from the end portion 4c of the first bag 4. As a result, a first composite molded body M1 and a second composite molded body M2 shown in FIG.

[0059] As described above, the first composite material W1 and the second composite material W2 can be molded to produce the first and second composite molded bodies M1, M2, respectively.

[0060] According to the manufacturing method of the composite molded body of the present embodiment, the second bag 5 expands against the force of the mandrel 3 being pushed back by the expansion of the end 4c of the first bag 4, and therefore the portion to be joined W2b is pressed more strongly against the portion to be joined W1b, thereby improving the shape accuracy of the portion to be joined M2b of the second composite molded body M2.

[0061] (Example 1) Next, a specific example of a method for producing a composite molded body according to the first embodiment will be described with reference to Fig. 12. Fig. 12 is a schematic diagram showing a specific example of a step of the method for producing a composite molded body according to the first embodiment.

[0062] As shown in Fig. 12, the mold 110 has the same configuration as the mold 10 shown in Fig. 6, except for the pipes 1e, 2e, and the mandrel 31. In Fig. 12, for ease of understanding, the upper film 4a and the lower film 4b are shown separated from each other, but in reality, similar to the mold 10 shown in Fig. 6, the upper film 4a and the lower film 4b are bonded together to form the first bag 4.

[0063] One end of the pipe 1e opens in the vicinity of the cavity surface 1d, and the other end of the pipe 1e is connected to a vacuum pump (not shown). Using this vacuum pump, the air between the upper film 4a and the first composite material W11 is exhausted through the pipe 1e, so that the upper film 4a can be attached to the second composite material W12 and the mandrel 31.

[0064] Similarly, one end of the pipe 2e opens in the vicinity of the cavity surface 2d, and the other end of the pipe 2e is connected to a vacuum pump (not shown). Using this vacuum pump, the air between the lower film 4b and the second composite material W12 and between the lower film 4b and the mandrel 31 is exhausted through the pipe 2e, thereby bonding the lower film 4b to the second composite material W12 and the mandrel 31.

[0065] The mandrel 31 is made of a silicone resin material.

[0066] Similar to the molding die 10 shown in FIG. 6, the molding die 110 can be used to carry out the method for producing a composite molded body according to the first embodiment.

[0067] (Example 2) Next, a specific example of a method for producing a composite molded body according to the second embodiment will be described with reference to Fig. 13. Fig. 13 is a schematic diagram showing a specific example of a step of the method for producing a composite molded body according to the second embodiment.

[0068] Except for the pipes 1e and 2e and the mandrel 32, the mold 120 has the same configuration as the mold 20 shown in Fig. 11. In Fig. 13, for ease of understanding, the upper film 4a and the lower film 4b are shown separated from each other, but in reality, the upper film 4a and the lower film 4b are bonded together to form the first bag 4, similar to the mold 10 shown in Fig. 11.

[0069] The mandrel 32 is made of pure aluminum or an aluminum alloy and has a higher elastic modulus or hardness than the mandrel 31 shown in FIG.

[0070] Similar to molding die 20 shown in FIG. 11, molding die 120 can be used to carry out the method for producing a composite molded body according to the second embodiment.

[0071] Here, the difference between a specific example of the manufacturing method of the composite molded body according to the second embodiment using the mold 120 and a specific example of the manufacturing method of the composite molded body according to the first embodiment using the mold 110 will be described. As described above, the mandrel 32 has a higher elastic modulus or hardness than the mandrel 31 shown in FIG. 12. Therefore, the shape accuracy of the joined portion M2b of the second composite molded body M2 formed by molding the second composite material W22 is higher than the shape accuracy of the joined portion M2b of the second composite molded body M2 formed by molding the second composite material W12. Therefore, the specific example of the manufacturing method of the composite molded body according to the second embodiment using the mold 120 can manufacture the second composite molded body M2 having the joined portion M2b with higher shape accuracy than the specific example of the manufacturing method of the composite molded body according to the first embodiment using the mold 110.

[0072] In step ST22, the second bag 5 expands due to the pressure P2 higher than the pressure P1 of the first bag 4, so that the second bag 5 presses the to-be-joined portion W2b against the to-be-joined portion W1b more strongly against the force of the mandrel 3 being pushed back by the first bag 4c. Therefore, the position of the mandrel 32 in the molding die 120 is more stable than the position of the mandrel 31 in the molding die 110. Therefore, in the specific example of the method for producing a composite molded body according to the second embodiment using the molding die 120, the position of the mandrel 32 is more stable than the specific example of the method for producing a composite molded body according to the first embodiment using the molding die 110. Therefore, the shape accuracy of the to-be-joined portion M2b of the second composite molded body M2 is stable.

[0073] (Embodiment 3) The method for producing a composite molded body according to the third embodiment will be described with reference to Figs. 14 to 17. Fig. 14 is a flow chart showing the method for producing a composite molded body according to the third embodiment. Fig. 15 is a schematic diagram showing a lower die in one step of the method for producing a composite molded body according to the third embodiment. Fig. 16 is a schematic diagram showing a cross section of the lower die shown in Fig. 15. Fig. 17 is a schematic diagram showing one step of the method for producing a composite molded body according to the third embodiment.

[0074] The method for producing a composite molded body according to this embodiment can be carried out, for example, by using a molding die 30 shown in FIG.

[0075] The mold 30 has the same configuration as the mold 20 shown in FIG. 11, except that the mold 30 includes a thermally expandable body 6 instead of the second bag 5 .

[0076] The thermal expansion body 6 may be made of a thermally expandable material. The thermal expansion body 6 may be made of, for example, a silicone rubber material. The thermal expansion body 6 may be appropriately heated and thermally expanded. The thermal expansion body 6 may be provided with, for example, a heating wire electrically connected to a power source. When the thermal expansion body 6 is placed in a room temperature environment, that is, when it is not heated and is not thermally expanded, it may have a shape that conforms to the inner wall surfaces of the first and second composite materials W1 and W2. In the manufacturing method of the composite molded body according to this embodiment, the thermal expansion body 6 functions as a pressing part that presses the mandrel 3. The thermal expansion body 6 does not need to be hollow like a bag, but is solid. The thermal expansion body 6 has a simple configuration compared to a bag such as the second bag 5.

[0077] 17, a mandrel 3, a first bag 4, and a thermally expandable body 6 are placed in a space C1 between the first and second composite materials W1, W2 placed in a molding die 30 (step ST31). The placed mandrel 3 is sandwiched between the first bag 4, the thermally expandable body 6, and the portions to be joined W1b, W2b of the first and second composite materials W1, W2. In the manufacturing method for a composite molded body according to this embodiment, the first bag 4 and the thermally expandable body 6 function as a pressing part that presses the mandrel 3.

[0078] Specifically, first, similarly to step ST11 shown in Fig. 1, each component is placed in the upper mold 1. That is, as shown in Fig. 2 and Fig. 3, the first composite material W1 is placed on the cavity surface 1d of the upper mold 1. Then, the upper film 4a is attached onto the first composite material W1.

[0079] 15 and 16, the second composite material W2 is placed on the cavity surface 2d of the lower die 2. Then, the mandrel 3 is placed on the second composite material W2, specifically, on a portion including the portion to be joined W2b. Then, the lower film 4b is attached to the second composite material W2 and the mandrel 3.

[0080] Next, the thermally expandable body 6 is placed on the lower film 4b. The mandrel 3 is sandwiched between the thermally expandable body 6 and the portion to be joined W2b of the second composite material W2.

[0081] Next, the upper mold 1 and the lower mold 2 are pressed together so that the cavity surface 1d and the cavity surface 2d face each other. In other words, the upper mold 1 and the lower mold 2 are clamped together. Then, the upper film 4a and the lower film 4b are bonded together to form the first bag 4. At this time, the upper mold 1 and the lower mold 2 are clamped and held with the necessary force by a clamping device such as a press (not shown) or bolts so that the mold does not open due to the later application of pressure to the first bag 4 or the thermal expansion of the thermally expandable body 6.

[0082] Next, the first bag 4 and the thermally expandable body 6 are expanded, and the mandrel 3 is pressed against the portion to be joined W2b of the second composite material W2 (step ST32).

[0083] Specifically, gas is supplied to the inside of the first bag 4 to pressurize it. Furthermore, the thermally expandable body 6 is heated to thermally expand it. It is preferable that the pressurization of the inside of the first bag 4 and the heating of the thermally expandable body 6 are performed approximately simultaneously. Furthermore, when the thermally expandable body 6 thermally expands, the pressure P3 in the thermally expandable body 6 is preferably larger than the pressure P1 in the first bag 4. Then, the first bag 4 and the thermally expandable body 6 expand and press the mandrel 3 toward the parts to be joined W1b, W2b (here, in the negative direction of the X-axis). As a result, the mandrel 3 presses against the parts to be joined W1b, W2b. Furthermore, the first and second composite materials W1, W2 are heated and hardened using a temperature regulator. More specifically, the parts to be joined W2b are heated while being pressed by the mandrel 3, so that the resin contained in the parts to be joined W2b is hardened. As a result, a first composite compact M1 and a second composite compact M2 shown in FIG. 7 are formed.

[0084] As described above, the first composite material W1 and the second composite material W2 can be molded to produce the first and second composite molded bodies M1, M2, respectively.

[0085] According to the manufacturing method of the composite molded body of this embodiment, the thermally expandable body 6 presses the mandrel 3 against the to-be-joined portion W2b of the second composite material W2 to manufacture the second composite molded body M2. The to-be-joined portion M2b of the second composite molded body M2 has high shape accuracy. Therefore, it is possible to improve the shape accuracy of the to-be-joined portions M1b, M2b of the first and second composite molded bodies M1, M2. In addition, it is possible to improve the shape accuracy of the to-be-joined portion M2b of the second composite molded body M2 by using the thermally expandable body 6, which has a simple configuration.

[0086] Furthermore, according to the manufacturing method of the composite molded body according to the present embodiment, the thermally expandable body 6 expands in response to the force of the mandrel 3 being pushed back by the expansion of the end 4c of the first bag 4, and thus the to-be-joined portion W2b is pressed more strongly against the to-be-joined portion W1b, thereby improving the shape accuracy of the to-be-joined portion M2b of the second composite molded body M2.

[0087] In addition, a composite joint can be obtained by joining the joint parts M1b, M2b of the first and second composite molded bodies M1, M2 shown in FIG. 7 to each other. The composite joint can be used as, for example, a wing or a propeller of an aircraft. When the composite joint is a propeller of an aircraft, the first composite molded body M1 and the second composite molded body M2 are skins, and the joined joint parts M1b, M2b are leading edge parts of the wing or the propeller of the aircraft. As described above, the shape accuracy of the joint parts M1b, M2b can be improved, so that the joined joint parts M1b, M2b have almost no gaps and have high adhesion. Therefore, the joined joint parts M1b, M2b are suitable as leading edge parts. The aircraft is, for example, an aircraft, eVTOL (Electric Vertical Take-Off and Landing Aircraft). In addition, a component such as a spar may be attached to the inside of the composite joint as appropriate.

[0088] The present invention is not limited to the above-described embodiment, and can be modified as appropriate without departing from the spirit and scope of the present invention. In addition, the present invention may be implemented by appropriately combining the above-described embodiment and examples thereof. [Explanation of symbols]

[0089] 10, 20, 30, 110, 120 molds 1 Upper mold 1a Upper mold body 1b Temperature control circuit 1c Seal 1d Cavity surface 1e Piping 2 Lower mold 2a Lower mold body 2b Temperature control circuit 2c Seal 2d Cavity surface 2e Piping 3, 31, 32 Mandrel 4. First Bag 4a Upper film 4b Lower film 4c end 5. Second Bag 6 Thermal expansion body C1 Space P1, P2, P3 Pressure ST11, ST12, ST21, ST22, ST31, ST32 process M1: First composite compact M2: Second composite compact M1a, M2a Main body M1b, M2b Part to be joined W1, W11, W21 1st composite W2, W12, W22 2nd composite W1a, W2a Main body W1b, W2b Part to be joined

Claims

1. A method for manufacturing a composite molded body, comprising molding a first composite material and a second composite material to form a first composite molded body and a second composite molded body, respectively, the method comprising the steps of: The first and second composite molded bodies each have a joinable portion that can be joined to each other, the joined portions of the first and second composite molded bodies are joined to each other to form a composite joint body; the first and second composite materials each have a portion to be joined corresponding to a portion to be joined of the first and second composite molded bodies, a step of arranging a mandrel and a pressing portion in a space sandwiched between first and second composite materials arranged in a molding die, the mandrel being sandwiched between the pressing portion and portions to be joined of the first and second composite materials; The pressing unit presses the mandrel against a portion to be joined of the second composite material. A method for producing a composite molded body.

2. In the step of the pressing unit pressing the mandrel against the portion of the second composite material to be joined, the pressing unit includes an inflatable first bag, and presses the mandrel against the portion of the second composite material to be joined by supplying a gas into the first bag to pressurize the inside of the first bag or by inflating the first bag. A method for producing the composite molded product according to claim 1.

3. the first bag has an end inserted between the portions to be joined of the first and second composite materials, and a gas is supplied into the first bag to pressurize the inside of the first bag or the first bag is expanded, whereby the end of the first bag presses the portions to be joined of the first composite material against the molding die; A method for producing the composite molded article according to claim 2.

4. In the step of pressing the mandrel against the portion to be joined of the second composite material by the pressing portion, The pressing unit further includes a second bag disposed in the first bag, supplying gas into the second bag to inflate the second bag; A method for producing the composite molding according to claim 2 or 3.

5. The pressure P2 in the second bag is greater than the pressure P1 in the first bag. A method for producing the composite molded article according to claim 4.

6. In the step of pressing the mandrel against the portion to be joined of the second composite material by the pressing portion, The pressing portion includes a thermal expansion body disposed in the first bag, The thermally expandable body is heated to cause thermal expansion. A method for producing the composite molding according to claim 2 or 3.

7. the composite joint is a propeller for an aircraft, In the composite joint, the joined portions of the first and second composite molded bodies are leading edges of the propeller of the aircraft. A method for producing the composite molded article according to claim 1 or 2.

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