Press-molding device and method for manufacturing press-molded body

Abstract

The present invention addresses the problem of, for example, providing a press-molding device capable of shortening the cycle of heating and cooling in the press molding of a fiber-reinforced composite material, and capable of manufacturing a press-molded body having high quality without a separate preheating device.　A press-molding device (1) is provided with a fixed mold (2) and a movable mold (3). The fixed mold (2) has a fixed mold base part (21), and a fixed mold intermediate part (22) provided with a fixed mold gap (2s) interposed between the fixed mold intermediate part (22) and the fixed mold base part (21). The movable mold (3) has a movable mold base part (31), and a movable mold intermediate part (32) provided with a movable mold gap (3s) interposed between the movable mold intermediate part (32) and the movable mold base part (31).

Description

Press-molding apparatus and method for manufacturing press-molded body

[0001] The present invention relates to a press-molding apparatus and a method for manufacturing a press-molded article made of a composite material, particularly a press-molding apparatus for a composite material at a press-molding temperature of 150°C or higher.

[0002] Composite materials have been developed as alternatives to metallic materials for forming automobile parts, electric motorcycles, separators for EV hydrogen engines, aircraft components, drone parts, prosthetic limbs, and the like. In particular, composite materials using thermoplastic resins or thermosetting resins have been attracting attention in recent years because they can be mass-produced by press molding and can be made into complex shapes.

[0003] Examples of resin-based composite materials used in press molding include GMT (glass mat reinforced thermoplastic), carbon fiber reinforced composite materials, natural fiber reinforced composite materials, and aramid fiber reinforced composite materials. For molding these composite materials, press molding methods such as those disclosed in Patent Document 1 are disclosed. However, the press molding temperature for composite materials is as high as 150°C or higher, which lengthens the heating and cooling cycle, resulting in problems such as low manufacturing efficiency and high manufacturing costs.

[0004] Furthermore, in order to produce high-quality press-molded bodies, it is desirable to preheat the material for the press-molded body before setting it in the press molding device (see, for example, Patent Document 2). However, depending on the shape of the material and the type of fibers contained in the composite, some materials are difficult to preheat (nonwoven fabrics, chopped materials, etc.), and even if preheating is possible, some materials are difficult to set in a mold after preheating. This has led to the problem that high-quality press-molded bodies cannot be obtained because they cannot be preheated.

[0005] Furthermore, when the upper and lower molds are closed entirely along guide pins or the like (when the molds are fully closed), there is the problem that it is difficult to adjust the guide pins, i.e., to position the mold parts and the press-molded body.

[0006] JP 2015-112827 A International Publication No. 2018 / 003433 A

[0007] The present invention has been made in consideration of the above circumstances, and aims to provide a press molding apparatus that can shorten the heating and cooling cycle in press molding of composite materials and produce high-quality press-molded products without a separate preheating device. Here, a "high-quality press-molded product" refers to a product in which the composite fibers and resin are sufficiently mixed so that there is little fiber exposure on the surface of the press-molded product, or a press-molded product that is molded with high precision even if the shape of the press-molded product is complex (a shape that includes bosses, ribs, thin-walled portions, undercut shapes, etc.) or even if there are problems with the homogeneity of the material.

[0008] The press molding device (1) for press-molding a composite press-molded body of the present invention comprises a fixed mold (2) and a movable mold (3), the fixed mold (2) having a fixed mold base (21) and a fixed mold intermediate part (22) arranged to sandwich a fixed mold gap (2s) together with the fixed mold base (21), and the movable mold (3) having a movable mold base (31) and a movable mold intermediate part (32) arranged to sandwich a movable mold gap (3s) together with the movable mold base (31). the fixed mold intermediate portion (22) and the movable mold intermediate portion (32) are arranged so as to face each other and be able to come into contact with each other, the fixed mold base portion (21) has a fixed mold base cooling flow path (211), the movable mold base (31) has a movable mold base cooling flow path (311), the fixed mold intermediate portion (22) has a fixed mold intermediate portion heating / cooling flow path (221) on the side of the fixed mold gap (2s), and the movable mold The movable mold intermediate part (32) has a movable mold intermediate part heating / cooling flow path (321) on the movable mold gap (3s) side, and the movable mold intermediate part has a movable mold intermediate part heater (322) on the side away from the movable mold gap (3s) and on the side of the fixed mold (2), and a heating fluid flows in the fixed mold intermediate part heating / cooling flow path (221) until a predetermined temperature is reached during preheating and heating, and a cooling fluid flows in the heating / cooling flow path (221) during cooling, and the movable mold A heating fluid flows through the mold intermediate heating and cooling flow path (321) during preheating and heating until a predetermined temperature is reached, and a cooling fluid flows through it during cooling. The width of the fixed mold gap (2s) and the movable mold gap (3s) can be adjusted, and the gap width can be set to 0 to eliminate the gap, allowing the fixed mold base (21) and the fixed mold intermediate part (22) to come into contact with each other, and the movable mold base (31) and the movable mold intermediate part (32) to come into contact with each other.

[0009] The method for manufacturing a press-molded body of a composite material using the press molding apparatus (1) of the present invention includes steps A, B, C, D, E, and F. Step A is a step of preheating the fixed mold intermediate part (22) and the movable mold intermediate part (32), configuring them to have the fixed mold gap (2s) and the movable mold gap (3s), bringing the fixed mold intermediate part (22) and the movable mold intermediate part (32) into contact with each other in a mold intermediate closed state, flowing a cooling fluid through the fixed mold base cooling flow channel (211) and the movable mold base cooling flow channel (311), and heating the fixed mold intermediate part (22). The step B is a step of flowing a heating fluid through the heat-cooling flow path (221) and the movable mold intermediate portion heating / cooling flow path (321), and turning on the fixed mold intermediate portion heater (222) and the movable mold intermediate portion heater (322) to heat the molded body. The step B is a step of applying a material for a press-molded body to the movable mold (3), and is configured to have the fixed mold gap (2s) and the movable mold gap (3s). The molds are opened so that the fixed mold intermediate portion (22) and the movable mold intermediate portion (32) are not in contact with each other, and the fixed mold base cooling flow path (211) and the movable mold base cooling flow path (311) are opened. a step C of flowing a cooling fluid through the fixed mold intermediate portion heating and cooling flow path (221) and the movable mold intermediate portion heating and cooling flow path (321), turning on the fixed mold intermediate portion heater (222) and the movable mold intermediate portion heater (322) to heat, and applying the material of the press-molded body to the movable mold (3) side; a step C of heating the material of the press-molded body, in which the fixed mold gap (2s) and the movable mold gap (3s) are configured, and the fixed mold intermediate portion (22) and the movable mold intermediate portion (32) are brought into contact with each other in a mold intermediate closed state; a step of flowing a cooling fluid through the fixed mold base cooling flow passage (211) and the movable mold base cooling flow passage (311), a heating fluid through the fixed mold intermediate portion heating / cooling flow passage (221) and the movable mold intermediate portion heating / cooling flow passage (321), and turning on the fixed mold intermediate portion heater (222) and the movable mold intermediate portion heater (322); a step D is a step of pressing the press-molded body, in which the width of the gap between the fixed mold gap (2s) and the movable mold gap (3s) is set to 0 to eliminate the gap, and the fixed mold intermediate portion (22) and the movable mold intermediate portion (32) are brought into contact with each other;The mold is closed so that the fixed mold base (21) and the fixed mold intermediate portion (22) come into contact with each other, and the movable mold base (31) and the movable mold intermediate portion (32) come into contact with each other, a cooling fluid is passed through the fixed mold base cooling flow path (211) and the movable mold base cooling flow path (311), a heating fluid is passed through the fixed mold intermediate portion heating / cooling flow path (221) and the movable mold intermediate portion heating / cooling flow path (321), and the fixed mold intermediate portion heater (222) and the movable mold intermediate portion heater (322) are turned ON. This is a step of cooling the intermediate portion (32) and the press-molded body, in which the widths of the fixed mold gap (2s) and the movable mold gap (3s) are set to 0 to eliminate the gaps, the fixed mold intermediate portion (22) and the movable mold intermediate portion (32) are brought into contact with each other, and the molds are closed so that the fixed mold base (21) and the fixed mold intermediate portion (22) are brought into contact with each other, and the movable mold base (31) and the movable mold intermediate portion (32) are brought into contact with each other, and a cooling fluid is passed through the fixed mold base cooling flow passage (211) and the movable mold base cooling flow passage (311), and the fixed mold intermediate portion heating and cooling flow passage (221) is passed through the fixed mold base cooling flow passage (211) and the movable mold base cooling flow passage (311) to cool the fixed mold intermediate portion heating and cooling flow passage (221). and the movable mold intermediate portion heating / cooling flow path (321), and turning off the fixed mold intermediate portion heater (222) and the movable mold intermediate portion heater (322). Step F is a step of removing the press-molded body, and is configured to have the fixed mold gap (2s) and the movable mold gap (3s), and is in a mold-open state so that the fixed mold intermediate portion (22) and the movable mold intermediate portion (32) are not in contact with each other, and is configured to have the fixed mold gap (2s) and the movable mold gap (3s), and is configured to have the fixed mold gap (2s ... heater (321), and is configured to have the fixed mold gap (2s) and the movable mold gap (3s), and is configured to have the fixed mold gap (2s) and the movable mold intermediate portion heater (321), and is configured to have the movable mold gap (3s), and is configured to have the fixed mold gap (2s) and the movable mold gap (3s), and is configured to have the fixed mold gap (2s) and the movable mold gap (3s), and is configured to have the fixed mold gap (2s) and the movable mold gap (3s), and is configured to have the fixed mold gap (2s) and the movable mold gap (3s), and is configured to have the fixed mold gap (2s) and the movable mold gap (321) are not in contact with each other, and is configured to have the movable mold gap (321). a step of flowing a cooling fluid through the fixed mold intermediate portion heating / cooling flow passage (221) and the movable mold intermediate portion heating / cooling flow passage (321), turning off the fixed mold intermediate portion heater (222) and the movable mold intermediate portion heater (322), and removing the press-molded body from the movable mold (3), wherein the supply of the heating fluid or cooling fluid flowing through the fixed mold intermediate portion heating / cooling flow passage (221) and the movable mold intermediate portion heating / cooling flow passage (321) is stopped when the fixed mold intermediate portion heating / cooling flow passage (221) and the movable mold intermediate portion heating / cooling flow passage (321) reach a predetermined temperature.

[0010] The press-molding device for press-molded bodies of the present invention shortens the heating and cooling cycle during press molding and can produce high-quality press-molded bodies without a separate preheating device. It is possible to press-mold materials that are difficult to preheat (such as nonwoven fabrics and chopped materials) or that are difficult to insert preheated materials into a mold. Furthermore, the press-molded body can be precisely molded even with complex shapes, with minimal exposure of fibers on the surface. Because the heating and cooling cycle during press molding can be shortened and positioning during pressing is easy, the production efficiency of press-molded bodies can be improved while reducing production costs. Furthermore, because the material for the press-molded body is heated while the fixed mold intermediate portion and the movable mold intermediate portion are in contact and the upper and lower molds are not fully closed (mold intermediate closure), positioning of mold components and the press-molded body is easier than when the molds are fully closed.

[0011] 1 is an example of a press forming apparatus of the present invention, showing a case where the fixed mold intermediate portion and the movable mold intermediate portion are not in contact (mold open state). 2 is an example of a press forming apparatus of the present invention, showing a case where the fixed mold intermediate portion and the movable mold intermediate portion are in contact (mold intermediate closed state). 3 is an example of a press forming apparatus of the present invention, showing a case where the fixed mold intermediate portion and the movable mold intermediate portion, the fixed mold base portion and the fixed mold intermediate portion, and the movable mold base portion and the movable mold intermediate portion are in contact (mold closed state). 4 is a graph showing the change in temperature over time when the press forming apparatus is in a mold open state and the temperature is increased from 50°C to 150°C. 5 is a graph showing the change in temperature over time when the press forming apparatus is in a mold open state and the temperature is increased from 50°C to 220°C. 6 is a graph showing the change in temperature over time when the press forming apparatus is in a mold open state and the temperature is increased from 50°C to 300°C. 7 is a graph showing the change in temperature over time when the press forming apparatus is in a mold intermediate closed state and the temperature is increased from 50°C to 150°C. 11(a) and (b) are 3D images, and FIGS. 11(c) and (d) are photographs. An example of a press-molded body manufactured using the press-molding apparatus of the present invention is shown. FIG. 12(a) is a photograph of the mold open state, and FIG. 12(b) is a photograph of the mold closed state.

[0012] The press-molding apparatus and the method for manufacturing a press-molded body of the present invention will be described below with reference to Figures 1 to 12. Although the description will be given using reference numerals, the present invention is not limited by the reference numerals.

[0013] (Press Molding Apparatus) The press molding apparatus 1 of the present invention is used to press mold a press-molded body made of a composite material such as a fiber-reinforced composite material.

[0014] When the composite material is a fiber-reinforced composite material, it contains fibers and synthetic resins.

[0015] Examples of fibers include glass fibers contained in GMT (glass mat reinforced thermoplastic), carbon fibers, natural fibers, aramid fibers, etc. Other usable fibers include metal fibers such as aluminum fibers, graphite fibers, organic fibers such as PBO (polyparaphenylene benzobisoxazole), polyphenylene sulfide, polyester, acrylic, nylon, and polyethylene, and inorganic fibers such as silicon carbide and silicon nitride.

[0016] An example of the synthetic resin is a thermoplastic resin such as polypropylene resin. Other thermoplastic resins that can be used include polyesters such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polytrimethylene terephthalate (PTT), polyethylene naphthalate (PEN), and liquid crystal polyester, polyolefins such as polyethylene (PE) and polybutylene, polyarylene sulfides such as polyoxymethylene (POM), polyamide (PA), and polyphenylene sulfide (PPS), fluorine-based resins such as polyketone (PK), polyether ketone (PEK), polyether ether ketone (PEEK), polyether ketone ketone (PEKK), polyether nitrile (PEN), and polytetrafluoroethylene, and crystalline resins such as liquid crystal polymer (LCP). In addition to styrene-based resins, amorphous resins such as polycarbonate (PC), polymethyl methacrylate (PMMA), polyvinyl chloride (PVC), polyphenylene ether (PPE), thermoplastic polyimide (PI), polyamideimide (PAI), polyetherimide (PEI), polysulfone (PSU), polyethersulfone, and polyarylate (PAR), as well as phenol-based resins, phenoxy resins, and thermoplastic elastomers such as polystyrene-based, polyolefin-based, polyurethane-based, polyester-based, polyamide-based, polybutadiene-based, polyisoprene-based, fluorine-based resins, and acrylonitrile-based thermoplastic elastomers, as well as copolymers and modified products thereof, can be used.

[0017] Furthermore, as the synthetic resin, thermosetting resins such as phenolic resin (PF), epoxy resin (MF), alkyd resin, silicone resin, polyurethane (PUP), thermosetting polyimide, melamine resin, and urea resin can be used.

[0018] The reinforcing fiber content of the fiber-reinforced composite material (before press molding) can be appropriately set within a range of about 20% by mass to 75% by mass. In order to mold a molded product with high physical strength, the reinforcing fiber content of the fiber-reinforced composite material can also be set to 50% by mass or more, or 60% by mass or more.

[0019] Examples of composite materials include fiber-reinforced composite materials as well as materials containing super engineering plastics and synthetic resins.

[0020] 1 and 2, a press forming apparatus 1 includes an opposing fixed mold 2 and a movable mold 3. Specifically, a fixed mold intermediate part 22 and a movable mold intermediate part 32 are arranged to face each other and be in contact with each other.

[0021] (Fixed Mold) The fixed mold 2 has a fixed mold base 21 and a fixed mold intermediate part 22 that is provided together with the fixed mold base 21 with a fixed mold gap 2s therebetween.

[0022] The material of the fixed mold base 21 is preferably carbon steel such as S45C. The size of the fixed mold base 21 depends on the size of the press-molded body, but is exemplified as approximately 50 cm x 70 cm x 10 cm thick. The material of the fixed mold intermediate part 22 is exemplified as various carbon steels, and pre-hardened steel such as PXA30 (carbon steel manufactured by Daido Steel Co., Ltd.) is often used from the viewpoint of mirror surface quality and hardness. The size of the fixed mold intermediate part 22 depends on the size of the press-molded body, but is exemplified as approximately 40 cm x 50 cm x 9 cm thick.

[0023] A fixed mold gap 2s is provided between the fixed mold base 21 and the fixed mold intermediate portion 22. The fixed mold gap 2s provides thermal insulation by sandwiching air between the fixed mold base 21 and the fixed mold intermediate portion 22. The fixed mold gap 2s is provided by attaching a fixed mold elastic body 23, such as a spring or coil, to the side of the fixed mold base 21 and / or the side of the fixed mold intermediate portion 22. The fixed mold elastic body 23 is preferably attached to the side of the fixed mold base 21 where a cooling fluid always flows. The width of the fixed mold gap 2s (the distance between the fixed mold base 21 and the fixed mold intermediate portion 22) is, for example, approximately 0 mm to 10 mm, and more preferably approximately 0 mm to 6 mm. When thermal insulation is required, a range of 4 mm to 6 mm is preferable. If the width is 10 mm or more, positioning of the mold components becomes difficult. The width of the fixed mold gap 2s can be adjusted using a fixed mold elastic body 23, such as a spring or coil, and a thickness adjustment bolt. When a certain amount of pressing force or more is applied between the fixed mold 2 and the movable mold 3, the fixed mold gap 2s becomes 0 mm, the gap disappears, and the fixed mold base 21 and the fixed mold intermediate part 22 come into contact with each other (see Figure 3).

[0024] A fixed mold insert 24 can be provided on the side of the fixed mold intermediate portion 22 opposite to the fixed mold base portion 21. The fixed mold insert 24, together with a movable mold insert 34 described later, is combined with the mold for compact 4 and is used to form the flat portion, the side wall, and the undercut portion.

[0025] The fixed mold intermediate portion 22 may be provided with a thermocouple 25 for measuring the mold temperature.

[0026] The fixed mold base 21 is provided with a fixed mold base cooling channel 211 through which a cooling fluid constantly flows during operation. The cooling fluid may be any cooling medium, such as cold water. The fixed mold base cooling channel 211 may be configured, for example, by arranging 24 pipes (12 pipes in two rows) with a diameter of 11 mm within the surface of the fixed mold base 21. In this case, the speed of the cooling fluid depends on the pipe diameter, the desired cooling temperature, the area of ​​the press-molded body, etc., but from the viewpoint of cooling efficiency, it is preferable to set the speed so that the flow is turbulent rather than laminar.

[0027] A fixed mold intermediate heating / cooling channel 221, through which a heating fluid or a cooling fluid flows, is provided on the side of the fixed mold gap 2s in the fixed mold intermediate section 22. A heating fluid can be flowed through the fixed mold intermediate heating / cooling channel 221 during preheating and heating until a predetermined temperature is reached, and a cooling fluid can be flowed through the fixed mold intermediate heating / cooling channel 221 during cooling.

[0028] The heating fluid may be any fluid capable of serving as a heating medium, and examples thereof include hot water, hot oil, and steam. The cooling fluid may be any fluid capable of serving as a cooling medium, and examples thereof include cold water. An example of the fixed mold intermediate portion heating / cooling flow path 221 is a configuration in which ten 11 mm diameter pipes (ten pipes per row) are arranged on the surface of the fixed mold intermediate portion 22 facing the fixed mold gap 2s. When the heating fluid is steam, the flow rate is adjusted by pressure. The speed of the cooling fluid depends on the pipe diameter, desired cooling temperature, area of ​​the press-molded body, etc., but from the viewpoint of cooling efficiency, it is preferable to set it so that the flow is turbulent rather than laminar.

[0029] The fixed mold intermediate part 22 is provided with a fixed mold intermediate part heater 222 on the side away from the fixed mold gap 2s and on the side of the movable mold 3. The fixed mold intermediate part heater 222 may be any heater capable of providing the desired heating, and an example of such a configuration is one in which 12 heaters, each 400 mm long and 8 mm in diameter, 10 A, 220 V, and 2000 W, are arranged (12 heaters in one row) on the surface of the fixed mold intermediate part 22 on the side away from the fixed mold gap 2s. Note that, for example, a hole is drilled in the fixed mold intermediate part 22 at the position of the fixed mold intermediate part heater 222, and the fixed mold intermediate part heater 222 is disposed in the hole.

[0030] (Movable Mold) The movable mold 3 has a movable mold base portion 31 and a movable mold intermediate portion 32 that is provided together with the movable mold base portion 31 and sandwiches a movable mold gap 3s therebetween.

[0031] The material of the movable mold base 31 is exemplified by various carbon steels, with S45C carbon steel, which is recognized by the JIS standard as carbon steel for mechanical structures, being preferred. The size of the movable mold base 31 is exemplified by approximately 50 cm x 70 cm x 10 cm thick. The material of the movable mold intermediate part 32 is exemplified by various carbon steels, with pre-hardened steels such as PXA30 (carbon steel manufactured by Daido Steel Co., Ltd.) being commonly used from the viewpoint of mirror finish quality and hardness. The size of the movable mold intermediate part 32 depends on the size of the press-molded product, but is exemplified by approximately 40 cm x 50 cm x 9 cm thick.

[0032] A movable mold gap 3s is provided between the movable mold base 31 and the movable mold intermediate portion 32. The movable mold gap 3s provides a heat insulating effect by sandwiching air between the movable mold base 31 and the movable mold intermediate portion 32. The movable mold gap 3s is provided by attaching a movable mold elastic body 33, such as a spring or coil, to the side of the movable mold base 31 and / or the side of the movable mold intermediate portion 32. The movable mold elastic body 33 is preferably attached to the side of the movable mold base 31, where a cooling fluid always flows. The width of the movable mold gap 3s (the distance between the movable mold base 31 and the movable mold intermediate portion 32) is, for example, approximately 0 mm to 10 mm, and more preferably approximately 0 mm to 6 mm. When a heat insulating effect is required, a range of 4 mm to 6 mm is preferable. If the width is 10 mm or more, positioning of the mold parts tends to be difficult. The width of the movable mold gap 3s can be adjusted using a movable mold elastic body 33, such as a spring or coil, and a thickness adjustment bolt, etc. When a certain amount of pressing force or more is applied between the fixed mold 2 and the movable mold 3, the movable mold gap 3s becomes 0 mm, the gap disappears, and the movable mold base 31 and the movable mold intermediate part 32 come into contact with each other (see Figure 3).

[0033] A movable mold insert 34 can be provided on the movable mold intermediate portion 32 on the side opposite to the movable mold base portion 31. The movable mold insert 34, together with the fixed mold insert 24, is combined with the molding die 4 and is used to form the flat portion, the side wall, and the undercut portion.

[0034] The movable mold base 31 is provided with a movable mold base cooling channel 311 through which a cooling fluid always flows during operation. The cooling fluid may be any cooling medium, such as cold water. The movable mold base cooling channel 311 may be configured, for example, by arranging 24 pipes (12 pipes in two rows) with a diameter of 11 mm within the surface of the movable mold base 31. In this case, the speed of the cooling fluid depends on the pipe diameter, the desired cooling temperature, the area of ​​the press-molded body, etc., but from the viewpoint of cooling efficiency, it is preferable to set the speed so that the flow is turbulent rather than laminar.

[0035] A movable mold intermediate heating / cooling channel 321 through which a heating fluid or a cooling fluid flows is provided on the movable mold gap 3s side of the movable mold intermediate section 32. A heating fluid can be flowed through the movable mold intermediate heating / cooling channel 321 during preheating and heating until a predetermined temperature is reached, and a cooling fluid can be flowed through the movable mold intermediate heating / cooling channel 321 during cooling.

[0036] The heating fluid may be any fluid capable of serving as a heating medium, and examples thereof include hot water, hot oil, and steam. The cooling fluid may be any fluid capable of serving as a cooling medium, and examples thereof include cold water. An example of the movable mold intermediate portion heating / cooling flow path 321 is a configuration in which ten 11 mm diameter pipes (ten pipes per row) are arranged on the surface of the movable mold intermediate portion 32 on the side of the movable mold gap 3s. When the heating fluid is steam, the flow rate is adjusted by pressure. The speed of the cooling fluid depends on the pipe diameter, the desired cooling temperature, the area of ​​the press-molded body, etc., but from the perspective of cooling efficiency, it is preferable to set it so that the flow is turbulent rather than laminar.

[0037] (Fixed mold intermediate part and movable mold intermediate part) The fixed mold intermediate part 22 and the movable mold intermediate part 32 are arranged to face each other and be able to come into contact with each other. In the "mold intermediate closed" and "mold closed" states described below, the fixed mold intermediate part 22 and the movable mold intermediate part 32 are in contact with each other, and in the "mold open" state, the fixed mold intermediate part 22 and the movable mold intermediate part 32 are not in contact with each other and face each other with a predetermined distance between them.

[0038] (Method for Producing Press-Molded Article) The press-molded article of the present invention includes steps A, B, C, D, E, and F.

[0039] Process A is a process for preheating the fixed mold intermediate portion 22 and the movable mold intermediate portion 32. Process A is performed in a mold intermediate closed state, with the fixed mold gap 2s and the movable mold gap 3s configured, and the fixed mold intermediate portion 22 and the movable mold intermediate portion 32 in contact with each other. A cooling fluid is passed through the fixed mold base cooling channel 211 and the movable mold base cooling channel 311, a heating fluid is passed through the fixed mold intermediate heating / cooling channel 221 and the movable mold intermediate heating / cooling channel 321, and the fixed mold intermediate portion heater 222 and the movable mold intermediate portion heater 322 are turned on for heating. The presence of the fixed mold gap 2s and the movable mold gap 3s provides a heat insulating effect that prevents the fixed mold base 21 and the movable mold base 31 from heating more than necessary. Furthermore, even if a cooling fluid is passed through the fixed mold base 21 and the movable mold base 31 to maintain the shape stability of the device, the heat insulating effect does not unnecessarily reduce the temperature rise efficiency of the fixed mold intermediate portion 22 and the movable mold intermediate portion 32.

[0040] Process B is a process in which the material for the press-molded body is applied to the movable mold 3. Process B is performed in an open mold state, with the molds configured to have a fixed mold gap 2s and a movable mold gap 3s, and so that the fixed mold intermediate section 22 and the movable mold intermediate section 32 are not in contact. A cooling fluid is passed through the fixed mold base cooling passage 211 and the movable mold base cooling passage 311, a heating fluid is passed through the fixed mold intermediate section heating / cooling passage 221 and the movable mold intermediate section heating / cooling passage 321, and the fixed mold intermediate section heater 222 and the movable mold intermediate section heater 322 are turned on to heat. In this state, the material for the press-molded body is applied to the movable mold intermediate section 32 side of the movable mold 3.

[0041] Step C is a process for heating the material of the press-molded body. Step C is performed in a mold-intermediate closed state, with the fixed mold gap 2s and movable mold gap 3s configured, and the fixed mold intermediate section 22 and the movable mold intermediate section 32 in contact with each other. A cooling fluid is passed through the fixed mold base cooling channel 211 and the movable mold base cooling channel 311, a heating fluid is passed through the fixed mold intermediate heating / cooling channel 221 and the movable mold intermediate heating / cooling channel 321, and the fixed mold intermediate heater 222 and the movable mold intermediate heater 322 are turned on to heat the body. Because the material of the press-molded body is a composite of materials with different properties, such as fiber and synthetic resin, it is desirable to ensure that the synthetic resin is sufficiently impregnated into the fibers before press molding and that there is minimal variation in the softness of the synthetic resin and the degree of fiber impregnation depending on the location of the press-molded product (near the center or near the edge, thick or thin section, etc.). For this reason, Steps B and C are performed after Step A.

[0042] Step D is a step of pressing the press-molded body. Step D is performed in a mold-closed state, with the gap widths of the fixed mold gap 2s and the movable mold gap 3s set to zero, eliminating the gaps, bringing the fixed mold intermediate portion 22 and the movable mold intermediate portion 32 into contact, and bringing the fixed mold base portion 21 and the fixed mold intermediate portion 22 into contact with each other, and the movable mold base portion 31 and the movable mold intermediate portion 32 into contact with each other. A cooling fluid is passed through the fixed mold base cooling channel 211 and the movable mold base cooling channel 311, a heating fluid is passed through the fixed mold intermediate heating / cooling channel 221 and the movable mold intermediate heating / cooling channel 321, and the fixed mold intermediate heater 222 and the movable mold intermediate heater 322 are turned on. In steps A, B, C, and D, water (steam) is used as the heating fluid. If the predetermined temperature is higher than 150°C, it is desirable to stop the supply of the heating fluid when the heating fluid reaches approximately 140°C to 150°C. When the supply is stopped, it is desirable to purge the stationary mold base cooling passage 211 and the movable mold base cooling passage 311 in preparation for the next cooling step.

[0043] Step E is a step of cooling the fixed mold intermediate portion 22, the movable mold intermediate portion 32, and the press-molded body. Step E is performed in a mold-closed state in which the gap widths of the fixed mold gap 2s and the movable mold gap 3s are set to 0 to eliminate any gaps, the fixed mold intermediate portion 22 and the movable mold intermediate portion 32 are brought into contact, and the fixed mold base portion 21 and the fixed mold intermediate portion 22 are brought into contact with each other, and the movable mold base 31 and the movable mold intermediate portion 32 are brought into contact with each other. A cooling fluid is flowed through the fixed mold base cooling channel 211 and the movable mold base cooling channel 311, and a cooling fluid is flowed through the fixed mold intermediate portion heating / cooling channel 221 and the movable mold intermediate portion heating / cooling channel 321, and the fixed mold intermediate portion heater 222 and the movable mold intermediate portion heater 322 are turned off. By eliminating the gaps by setting the width of the fixed mold gap 2s and the movable mold gap 3s to zero, the cooling fluid flowing through the fixed mold base cooling channel 211 and the movable mold base cooling channel 311 can also contribute to cooling, improving cooling efficiency. Note that in step E, it is desirable to stop the supply of cooling fluid once a predetermined temperature is reached.

[0044] Step F is a step of removing the press-molded body. Step F is performed in an open mold state, with the molds configured to have a fixed mold gap 2s and a movable mold gap 3s, and with the fixed mold intermediate section 22 and the movable mold intermediate section 32 not in contact with each other. A cooling fluid is allowed to flow through the fixed mold base cooling passage 211 and the movable mold base cooling passage 311, and through the fixed mold intermediate section heating / cooling passage 221 and the movable mold intermediate section heating / cooling passage 321. The fixed mold intermediate section heater 222 and the movable mold intermediate section heater 322 are turned off, and the press-molded body is removed from the movable mold 3.

[0045] As described above, one of the main features of the press molding apparatus and method for manufacturing a press-molded product of the present invention is that, when heating using the fixed mold intermediate portion 22 and the movable mold intermediate portion 32, the heater is located on the press-molded product side, the heating / cooling channels are located on the mold base side, and a heating fluid flows through them. Furthermore, thermal insulation is provided from the fixed mold base 21 and the movable mold base 31 by the fixed mold gap 2s and the movable mold gap 3s, respectively. Another feature is that, when cooling, the widths of the fixed mold gap 2s and the movable mold gap 3s are set to zero, bringing the fixed mold base 21 and the fixed mold intermediate portion 22 into contact with each other, and the movable mold base 31 and the movable mold intermediate portion 32 into contact with each other, allowing the cooling fluid flowing through the fixed mold base cooling channel 211 and the movable mold base cooling channel 311 to also contribute to cooling. These features enable high-quality press-molded products to be obtained while shortening the heating and cooling cycle, even when using complex shapes or composite materials that are not suitable for preheating.

[0046] (Evaluation test of heating by heater and heating fluid) Using the press molding apparatus of the present invention, the heating time by heater and steam (heating fluid) until a predetermined temperature was reached was evaluated. Similarly, the heating time by only a conventional heater was evaluated to verify the shortened time.

[0047] Evaluations were conducted with the mold open and with the mold partially closed, and the time required for the temperature to reach 150°C from 50°C, 220°C from 50°C, and 300°C from 50°C were measured. The supply of steam was stopped when the mold temperature reached 140°C, compressed air was purged for 10 seconds, and the valve was closed. The evaluation results are shown in Figures 4 to 9 and Table 1. For reference data, the heating time using steam alone was measured with the mold open and with the mold partially closed, and is shown in Figure 10.

[0048]

[0049] Figures 4 to 9 and Table 1 show that significant time reductions were achieved: 34 to 101 seconds when the mold was open, and 53 to 115 seconds when the mold was partially closed. Because steam supply was stopped when the mold temperature reached 140°C, heating times were reduced by 1 to 2 minutes when heating from 50°C to 220°C or from 50°C to 300°C, even though heating was performed using only the heater. Figure 10 also shows that heating to 150°C using steam alone took 1,155 seconds when the mold was open and 917 seconds when the mold was partially closed, which were 6.7 and 5.3 times longer than when using only the heater (172 seconds, as shown in Figure 4, and 173 seconds, as shown in Figure 7). These results suggest that although steam alone has lower heating efficiency than heater alone, using steam in combination with a heater in the initial heating stage significantly reduced heating time and increased heater heating efficiency in the latter stages after steam supply was stopped. In particular, by arranging the heater on the press-molded body side and the steam flow path on the opposite side to the press-molded body, the thermal efficiency can be further improved.

[0050] On the other hand, during cooling, cooling fluid flows through the fixed mold intermediate heating / cooling passage 221 and the movable mold intermediate heating / cooling passage 321, thereby shortening the cooling time.

[0051] Figure 11 shows an example of a press-molded body (320 mm x 230 mm, molded from a composite material of polyamide resin and carbon fiber nonwoven fabric) produced using the press molding apparatus of the present invention. Figure 11(a) is a 3D image of the back side, Figure 11(b) is a 3D image of the front side, Figure 11(c) is a photograph of the back side, and Figure 11(d) is a photograph of the front side. As shown, high-quality press-molded bodies can be obtained even with unevenness, ribs, thick and thin parts.

[0052] An example of the press molding apparatus of the present invention is shown in Figure 12. Figure 12(a) shows the mold open state, and Figure 12(b) shows the mold partially closed state, with a fixed mold gap 2s and a movable mold gap 3s.

[0053] In this specification, the upper side of the press molding apparatus is described as a "fixed mold" and the lower side as a "movable mold," but the upper side may be a movable mold and the lower side may be a fixed mold. Also, both the upper and lower sides may be movable molds.

[0054] REFERENCE SIGNS LIST 1 Press molding device 2 Fixed mold 21 Fixed mold base 211 Fixed mold base cooling channel 22 Fixed mold intermediate section 221 Fixed mold intermediate section heating / cooling channel 222 Fixed mold intermediate section heater 23 Fixed mold elastic body 24 Fixed mold insert 25 Thermocouple 2s Fixed mold gap 3 Movable mold 31 Movable mold base 311 Movable mold base cooling channel 32 Movable mold intermediate section 321 Movable mold intermediate section heating / cooling channel 322 Movable mold intermediate section heater 33 Movable mold elastic body 34 Movable mold insert 3s Movable mold gap 4 Molded body mold 5 Drive section

Claims

1. A press molding apparatus (1) for press-molding a composite press-molded body, the press molding apparatus (1) comprising: a fixed mold (2) and a movable mold (3); the fixed mold (2) has a fixed mold base (21) and a fixed mold intermediate part (22) arranged with the fixed mold base (21) and sandwiching a fixed mold gap (2s); the movable mold (3) has a movable mold base (31) and a movable mold intermediate part (32) arranged with the movable mold base (31) and sandwiching a movable mold gap (3s); the fixed mold intermediate part (22) and the movable mold intermediate part (32) are arranged to face each other and be in contact with each other; the fixed mold base (21) has a fixed mold base cooling flow passage (211); and the movable mold base (31) has a movable mold base cooling flow passage (311); the fixed mold intermediate portion (22) has a fixed mold intermediate portion heating and cooling flow passage (221) on the fixed mold gap (2s) side, and a fixed mold intermediate portion heater (222) on the side remote from the fixed mold gap (2s) and on the side of the movable mold (3); the movable mold intermediate portion (32) has a movable mold intermediate portion heating and cooling flow passage (321) on the movable mold gap (3s) side, and a movable mold intermediate portion heater (322) on the side remote from the movable mold gap (3s) and on the side of the fixed mold (2); a heating fluid flows in the fixed mold intermediate portion heating and cooling flow passage (221) during preheating and heating until a predetermined temperature is reached, and a cooling fluid flows during cooling; a heating fluid flows in the movable mold intermediate portion heating and cooling flow passage (321) during preheating and heating until a predetermined temperature is reached, and a cooling fluid flows during cooling; The press molding device (1) is capable of adjusting the width of the fixed mold gap (2s) and the movable mold gap (3s), and is capable of eliminating the gap by setting the gap width to zero, thereby bringing the fixed mold base (21) and the fixed mold intermediate portion (22) into contact with each other, and the movable mold base (31) and the movable mold intermediate portion (32) into contact with each other.

2. A method for producing a press-molded body of a composite material by the press molding apparatus (1) according to claim 1, the method comprising steps A, B, C, D, E and F, wherein step A is a step of preheating the fixed mold intermediate part (22) and the movable mold intermediate part (32), configuring the fixed mold gap (2s) and the movable mold gap (3s), bringing the fixed mold intermediate part (22) and the movable mold intermediate part (32) into contact with each other in a mold intermediate closed state, flowing a cooling fluid through the fixed mold base cooling passage (211) and the movable mold base cooling passage (311), flowing a heating fluid through the fixed mold intermediate part heating / cooling passage (221) and the movable mold intermediate part heating / cooling passage (321), and turning on the fixed mold intermediate part heater (222) and the movable mold intermediate part heater (322) to heat the molds, The B step is a step of applying a material for a press-molded body to the movable mold (3), which is configured to have the fixed mold gap (2s) and the movable mold gap (3s), which is in a mold open state so that the fixed mold intermediate part (22) and the movable mold intermediate part (32) are not in contact with each other, which causes a cooling fluid to flow through the fixed mold base cooling passage (211) and the movable mold base cooling passage (311), which causes a heating fluid to flow through the fixed mold intermediate part heating / cooling passage (221) and the movable mold intermediate part heating / cooling passage (321), which causes the fixed mold intermediate part heater (222) and the movable mold intermediate part heater (322) to be turned ON to heat the movable mold (3), and which applies the material for the press-molded body to the movable mold (3) side. Process C is a process of heating the material of the press-molded body, which is configured to have the fixed mold gap (2s) and the movable mold gap (3s), which is in a mold intermediate closed state in which the fixed mold intermediate part (22) and the movable mold intermediate part (32) are in contact with each other, which causes a cooling fluid to flow through the fixed mold base cooling passage (211) and the movable mold base cooling passage (311), which causes a heating fluid to flow through the fixed mold intermediate part heating / cooling passage (221) and the movable mold intermediate part heating / cooling passage (321), and which turns on the fixed mold intermediate part heater (222) and the movable mold intermediate part heater (322) to heat the body,Step D is a step of pressing the press-molded body, in which the gap widths of the fixed mold gap (2s) and the movable mold gap (3s) are set to 0 to eliminate the gaps, the fixed mold intermediate portion (22) and the movable mold intermediate portion (32) are brought into contact with each other, the fixed mold base portion (21) and the fixed mold intermediate portion (22) are brought into contact with each other, and the movable mold base portion (31) and the movable mold intermediate portion (32) are brought into contact with each other in a mold-closed state, a cooling fluid is caused to flow through the fixed mold base cooling passage (211) and the movable mold base cooling passage (311), a heating fluid is caused to flow through the fixed mold intermediate portion heating / cooling passage (221) and the movable mold intermediate portion heating / cooling passage (321), and the fixed mold intermediate portion heater (222) and the movable mold intermediate portion heater (322) are turned ON, Step E is a step of cooling the fixed mold intermediate part (22), the movable mold intermediate part (32), and the press molded body, and is a step of setting the gap widths of the fixed mold gap (2s) and the movable mold gap (3s) to 0 to eliminate the gaps, bringing the fixed mold intermediate part (22) and the movable mold intermediate part (32) into contact with each other, bringing the fixed mold base (21) and the fixed mold intermediate part (22) into contact with each other, and the movable mold base (31) and the movable mold intermediate part (32) into contact with each other in a mold closed state, flowing a cooling fluid through the fixed mold base cooling flow passage (211) and the movable mold base cooling flow passage (311), flowing a cooling fluid through the fixed mold intermediate part heating / cooling flow passage (221) and the movable mold intermediate part heating / cooling flow passage (321), and turning off the fixed mold intermediate part heater (222) and the movable mold intermediate part heater (322). Step F is a step of removing the press-molded body, which is configured to have the fixed mold gap (2s) and the movable mold gap (3s), is in a mold open state so that the fixed mold intermediate part (22) and the movable mold intermediate part (32) are not in contact with each other, a cooling fluid is caused to flow through the fixed mold base cooling passage (211) and the movable mold base cooling passage (311), a cooling fluid is caused to flow through the fixed mold intermediate part heating / cooling passage (221) and the movable mold intermediate part heating / cooling passage (321), the fixed mold intermediate part heater (222) and the movable mold intermediate part heater (322) are turned off, and the press-molded body is removed from the movable mold (3);A method for manufacturing a press-molded body, characterized in that the supply of heating fluid or cooling fluid to the fixed mold intermediate section heating / cooling passage (221) and the movable mold intermediate section heating / cooling passage (321) is stopped when the fixed mold intermediate section heating / cooling passage (221) and the movable mold intermediate section heating / cooling passage (321) reach a predetermined temperature.

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