Integrated molded article and method for manufacturing integrated molded article

Abstract

In an integrally molded article of a structural member and a resin structural member, deformation of the structural member that may occur during integral molding is suppressed, and an integrally molded article having high weight and dimensional accuracy is achieved. An integrally molded article provided with a structural member (a), a resin structural member (b), and a fixing member (c), characterized in that the fixing member (c) is in contact with both the structural member (a) and the resin structural member (b), and the softening point Tb (DEG C) of the resin structural member (b) and the softening point Tc (DEG C) of the fixing member (c) satisfy the following relationship. Tcgt; Tcgt; tb

Description

Technical Field

[0001] The present invention relates to an integrated molded product and a method for manufacturing the same. Background Art

[0002] Fiber reinforced resin is a material with excellent mechanical properties and lightness, and is widely used as a structural component of aircraft, automobiles, industrial equipment, etc. In such applications, a frame structure with a fiber reinforced resin tube as the main skeleton is sometimes adopted. In this case, it is necessary to form a part of the fiber reinforced resin frame material that can be connected or detached, but the shape of such parts is relatively complex, so they are usually manufactured separately by injection molding, etc., and fixed to the frame material using bolts / rivets, adhesives. For example, Patent Document 1 discloses a frame structure formed by joining a carbon fiber reinforced resin tube and a joint using an adhesive and a rivet. In addition, Patent Document 2 discloses a frame structure in which a joint is embedded in the tube lumen and an adhesive is flowed into the gap formed by the tube lumen surface and the joint embedding portion surface.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 62-295372

[0006] Patent Document 2: Japanese Patent Application Laid-Open No. 2020-101288 Summary of the Invention

[0007] Problems to be solved by the invention

[0008] In order to ensure the reliability of the joint using adhesive, the adhesive is usually applied generously and any excess adhesive that overflows is removed after curing. However, the adhesive removal operation is burdensome and becomes a problem particularly in mass production. In addition, the surface of the component is sometimes damaged during the removal operation based on grinding or the like. Therefore, there is also a method of forming other resin structural components on the surface of the structural component by injection molding, but there is a possibility that the structural component itself may be deformed due to the heat conduction of the injected resin. If the structural component itself is deformed, not only will the mechanical properties be reduced, but the resin will also flow into the deformed portion, resulting in a problem of increased weight of the molded product.

[0009] An object of the present invention is to provide an integrally molded product comprising a structural component and a resin structural component, wherein deformation of the structural component that may occur during the integral molding can be suppressed.

[0010] Means for solving problems

[0011] The present invention for solving the above-mentioned problems includes the following aspects.

[0012] (1) An integrally molded article comprising a structural member (a), a resin structural member (b), and a fixing member (c), characterized in that:

[0013] The fixing member (c) is in contact with both the structural member (a) and the resin structural member (b).

[0014] The softening point Tb (° C.) of the resin structural member (b) and the softening point Tc (° C.) of the fixing member (c) satisfy the following relationship.

[0015] Tc>Tb

[0016] (2) The integrated molded article according to (1) is characterized in that the glass transition temperature Ta (°C) of the structural member (a) and the softening point Tc (°C) of the fixing member (c) satisfy the following relationship.

[0017] Tc>Ta

[0018] (3) The integrated molded product as described in (2) is characterized in that the glass transition temperature Ta (°C) of the aforementioned structural component (a), the softening point Tb (°C) of the aforementioned resin structural component (b), and the softening point Tc (°C) of the aforementioned fixing component (c) satisfy the following relationship.

[0019] 10 <Tc-Ta<180

[0020] 5 <Tc-Tb<80

[0021] (4) The integrally molded article according to (1), wherein the structural component (a) is a structural component having an internal space, and the structural component (a) and the resin structural component (b) are in contact and joined at least partially.

[0022] (5) The integrally molded article according to (1), wherein the structural component (a) is a structural component having an open internal space, and the fixing component (c) is a component that covers at least a portion of the opening of the structural component (a).

[0023] (6) An integrated molded article as described in (1), wherein the aforementioned structural component (a) is a structural component having an open cylindrical portion, and the aforementioned cylindrical portion of the aforementioned structural component (a) and the aforementioned resin structural component (b) are in contact and joined at least a portion of the outer wall or inner wall of the aforementioned cylindrical portion.

[0024] (7) The integrally molded article according to (6), wherein the cylindrical portion of the structural component (a) and the resin structural component (b) are joined via a thermoplastic resin at at least a portion of the outer wall or inner wall of the cylindrical portion.

[0025] (8) The integrally molded article according to (6), wherein the structural component (a) is substantially formed of a carbon fiber reinforced thermosetting resin,

[0026] A thermoplastic resin layer is disposed on at least a portion of an outer wall or an inner wall of the structural component (a), the resin structural component (b) is an injection-molded body, the structural component (a) and the resin structural component (b) are joined via the thermoplastic resin layer of the structural component (a), and at least a portion of an opening of the structural component (a) is covered by the fixing component (c).

[0027] (9) An integrated molded article as described in (8), wherein the resin structural component (b) is formed of a carbon fiber reinforced thermoplastic resin, and the fixing component (c) is formed of a material having a linear expansion coefficient larger than the linear expansion coefficient of the material constituting the structural component (a).

[0028] (10) The integrated molded article according to (8), wherein the resin structural member (b) is formed of a carbon fiber reinforced thermoplastic resin, and the fixing member (c) is formed of a carbon fiber reinforced thermoplastic resin or metal.

[0029] (11) An integrated molded article as described in (8), wherein the resin structural component (b) is formed of a carbon fiber reinforced thermoplastic resin, the fixing component (c) is formed of a carbon fiber reinforced thermoplastic resin having a softening point (°C) higher than the melting point (°C) of the resin structural component (b), and the fixing component (c) is present between the internal space of the structural component (a) and the resin structural component (b).

[0030] (12) The integrally molded article according to (6), wherein at least a portion of the fixing member (c) has a size equal to or larger than the inner diameter of the cylindrical portion of the structural member (a).

[0031] (13) An integrated molded article as described in (6), wherein the distance between the following boundary surface and the end of the aforementioned structural component (a) is 0 to 50 mm, and the boundary surface is the boundary surface between the internal space in the aforementioned cylindrical portion of the aforementioned structural component (a) and the aforementioned fixing component (c).

[0032] (14) The integrally molded article according to (1), wherein the fixing member (c) has a thickness of 0.4 to 10 mm.

[0033] (15) The integrally molded article according to (6), wherein the ratio of the opening area of ​​the structural member (a) closed by the fixing member (c) is 40 to 100%.

[0034] (16) The integrated molded article as described in (6), wherein the area (L1) where the structural component (a) and the fixing component (c) meet is 50 to 200% of the area (L2) where the structural component (a) and the resin structural component (b) meet.

[0035] (17) An integrated molded article as described in (1), wherein the fixing member (c) is substantially formed of a thermoplastic resin, and the difference in Hansen solubility parameter (HSP value) between the resin structural member (b) and the fixing member (c) is 0 to 2 (J / cm 3 ) 1 / 2 .

[0036] (18) The integrally molded article according to (6), wherein the structural component (a) is a tube, and the resin structural component (b) is a joint or a base.

[0037] (19) A frame structure formed using the integrally molded product described in (18).

[0038] (20) An aircraft, which is formed using the integrated molded product described in (18).

[0039] (21) The aircraft according to (20), wherein the length of the structural component (a) is not less than 0.05 m and not more than 3 m.

[0040] (22) The aircraft as described in (20), wherein the main body weight is less than 1000 kg.

[0041] (23) The aircraft as described in (20) is a multi-rotor type equipped with three or more rotors.

[0042] (24) A method for manufacturing an integrally molded article, wherein a fixing member (c) covering the aforementioned opening of a structural member (a) having a cylindrical portion substantially formed of a fiber-reinforced resin with an opening at least at one end is arranged on the structural member (a), and a resin structural member (b) is joined in a manner so as to be in contact with at least a portion of the outer wall or inner wall of the aforementioned cylindrical portion of the structural member (a).

[0043] (25) A method for manufacturing an integrated molded product as described in (24), wherein, in a state where the structural component (a) is fixed to the mold cavity of the injection molding mold and a fixing component (c) is provided to cover the aforementioned opening of the aforementioned cylindrical portion, the molten thermoplastic resin is caused to flow in contact with at least a portion of the outer wall or inner wall of the aforementioned cylindrical portion of the structural component (a), and the thermoplastic resin is solidified while applying a holding pressure to thereby injection mold the resin structural component (b) and join it to the aforementioned cylindrical portion of the structural component (a).

[0044] Effects of the Invention

[0045] According to the present invention, in the above-mentioned integrally molded article, deformation of structural components that may occur during integral molding can be suppressed, and an integrally molded article having high weight and dimensional accuracy can be obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] [ Figure 1 ] is a schematic external view showing an example of a joint as a resin structural component (b).

[0047] [ Figure 2 ] is a schematic external view showing an example of a base as a resin structural component (b).

[0048] [ Figure 3 ]To show that Figure 1 The connector shown, Figure 2 The schematic diagram of the appearance of an example of an integrally molded article formed by joining a base and a structural member (a) is shown.

[0049] [ Figure 4 ] is a cross-sectional view showing an example of the fitting state of the fixing component (c) at the cylindrical portion of the structural component (a).

[0050] [ Figure 5 ] is a cross-sectional view showing the dimensions of the fixing component (c) arranged at the end of the cylindrical portion of the structural component (a). DETAILED DESCRIPTION

[0051] Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

[0052] The shape of the structural component (a) is not particularly limited, and shapes having an internal space or a cylindrical portion with at least one end being open can be suitably used. The so-called cylindrical shape refers to a shape having an elongated inner cavity divided by an outer wall. The cross-sectional shape of the outer wall is not limited to a circle, and can also be an elliptical, polygonal, or irregular cross-section, preferably a circle or polygon. The cylindrical portion can also be curved in the longitudinal direction. In addition, the structural component (a) can also be a component consisting only of a cylindrical portion, that is, a component that is entirely tubular.

[0053] The structural component (a) is preferably a component whose cylindrical portion is substantially formed of a fiber-reinforced resin. It may also be a component that does not contain reinforcing fibers outside the cylindrical portion, a component that has been joined to other components that are also made of fiber-reinforced resin or are not made of fiber-reinforced resin, and more preferably a component that is substantially formed of fiber-reinforced resin as a whole. Here, the so-called substantially formed of fiber-reinforced resin means that the majority of it is composed of a resin containing reinforcing fibers, but there may be a portion that does not contain reinforcing fibers locally. For example, in the method described later in which a thermoplastic resin layer for bonding is arranged on the surface layer of the cylindrical portion, even if the thermoplastic resin layer does not contain reinforcing fibers, as long as the resin portion containing reinforcing fibers dominates the entire cylindrical portion, it is considered to be substantially formed of fiber-reinforced resin. It should be noted that, typically, more than 80% by volume of the cylindrical portion, preferably more than 90% by volume, is fiber-reinforced resin.

[0054] The cross-sectional area of ​​the cylindrical portion (the cross-sectional area of ​​the cross section perpendicular to the longitudinal direction. Hereinafter, in this specification, unless otherwise specified, the cross section of the cylindrical portion refers to the cross section perpendicular to the longitudinal direction. In addition, when the cylindrical portion is curved, it refers to the cross section perpendicular to the tangent line of the curve connecting the centers of the cavities.) is preferably 20 mm 2 More than 50 mm, more preferably 2 Above, preferably 300mm 2 Below, more preferably 200mm 2 When the cross-sectional area of ​​the cylindrical body (a) is within the above-mentioned range, a highly rigid integrated molded product can be obtained with good productivity.

[0055] The reinforcing fibers contained in the fiber-reinforced resin are not particularly limited, and examples thereof include glass fibers, polyacrylonitrile-based, rayon-based, lignin-based, and pitch-based carbon fibers (including graphite fibers), potassium titanate whiskers, zinc oxide whiskers, calcium carbonate whiskers, wollastonite whiskers, aluminum borate whiskers, aramid fibers, alumina fibers, silicon carbide fibers, ceramic fibers, asbestos fibers, gypsum fibers, and metal fibers. Among these, glass fibers, polyacrylonitrile-based, and pitch-based carbon fibers are preferred. From the viewpoint of lightness and mechanical properties, polyacrylonitrile-based or pitch-based carbon fibers are more preferred, and polyacrylonitrile-based carbon fibers are particularly preferred.

[0056] From the viewpoint of improving mechanical properties, it is preferable to surface-treat the reinforcing fibers with a sizing agent. Examples of the sizing agent include multifunctional epoxy resins, acrylic polymers, polyols, polyethylene imine, and more specifically, polyglycidyl ethers of aliphatic polyols such as glycerol triglycidyl ether, diglycerol polyglycidyl ether, polyglycerol polyglycidyl ether, sorbitol polyglycidyl ether, arabitol polyglycidyl ether, trimethylolpropane triglycidyl ether, and pentaerythritol polyglycidyl ether, polyacrylic acid, copolymers of acrylic acid and methacrylic acid, and copolymers of acrylic acid and maleic acid. A copolymer of an acid, or a mixture of two or more thereof, polyvinyl alcohol, glycerol, diglycerol, polyglycerol, sorbitol, arabitol, trimethylolpropane, pentaerythritol, polyethyleneimine containing more amino groups in one molecule, etc. Among these, glycerol triglycidyl ether, diglycerol polyglycidyl ether, and polyglycerol polyglycidyl ether can be preferably used in the present invention because they contain more highly reactive epoxy groups in one molecule and have high water solubility and are easy to apply to fibers.

[0057] The reinforcing fibers contained in the structural component (a) are preferably continuous fibers. Here, the continuous fibers in this specification refer to fibers having a length of 10 mm or more. As long as they have this length, they do not necessarily have to be continuous fibers throughout the entire fiber-reinforced component and can also be cut in the middle. Examples of the continuous fiber form include a form of a fabric woven with fiber bundles, a form in which filaments, braids, filament bundles, spun yarns, etc. are stretched in one direction. The structural component (a) can also be formed by combining two or more of these reinforcing fiber forms.

[0058] The type of resin constituting the fiber-reinforced resin is not particularly limited, and is preferably a thermosetting resin. As a thermosetting resin, for example, unsaturated polyester resin, vinyl ester resin, epoxy resin, phenolic (Resol type) resin, urea melamine resin, polyimide resin, etc., their copolymers, modified products, and resins obtained by blending at least two of them can be cited. Among these, thermosetting resins with epoxy resin as the main component are excellent in rigidity and strength, and are therefore more preferred from the perspective of the mechanical properties of the molded product. It should be noted that the main component in the so-called thermosetting resin refers to the component ratio in the thermosetting resin that accounts for 60% by mass or more. In the fiber-reinforced thermosetting resin, other fillers and additives may also be contained depending on the purpose, etc. For example, elastomers or rubber components, inorganic fillers, flame retardants, conductivity imparting agents, antibacterial agents, insect repellents, deodorants, anti-coloring agents, release agents, antistatic agents, plasticizers, colorants, pigments, dyes, foaming agents, foaming agents, coupling agents, etc. can be cited.

[0059] The thermoplastic resin constituting the resin structural member (b) is not particularly limited, and examples thereof include polyolefin resins such as polyethylene and polypropylene, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate (PEN), polybutylene naphthalate (PBN), polyester resins such as liquid crystal polyester, polycaprolactam (nylon 6), polyhexamethylene adipamide (nylon 66), polypentamethylene adipamide (nylon 56), polyhexamethylene sebacamide (nylon 610), polydodecane diols, and the like. Hexamethylenediamine (nylon 612), polyundecalactam (nylon 11), polylaurolactam (nylon 12), polycaprolactam / polyhexamethyleneadipamide copolymer (nylon 6 / 66), polycaprolactam / polyhexamethyleneterephthalamide copolymer (nylon 6 / 6T), polyhexamethyleneadipamide / polyhexamethyleneterephthalamide copolymer (nylon 66 / 6T), polyhexamethyleneadipamide / polyhexamethyleneisophthalamide copolymer (nylon 66 / 6I), polyhexamethyleneadipamide / polyhexamethyleneisophthalamide copolymer Polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (nylon 6T / 6I), polyhexamethylene terephthalamide / polylaurolactam copolymer (nylon 6T / 12), polyhexamethylene adipamide / polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (nylon 66 / 6T / 6I), polyhexamethylene terephthalamide / poly-2-methylpentamethylene terephthalamide copolymer (nylon 6T / M5T), poly Polyamide resins such as nonane terephthalamide (nylon 9T), polycarbonate resins, polyphenylene sulfide (PPS) resins, polyacetal resins or polyoxymethylene resins, polyimide (PI) resins, polyamideimide (PAI) resins, polyetherimide resins, polysulfone resins, polyetherketone (PEK) resins, polyetheretherketone (PEEK) resins, polyetherketoneketone (PEKK) resins, polytetrafluoroethylene resins, polyarylate (PAR) resins, and resins blended with at least two of these. Among them, polyolefin resins, polyester resins, polyamide resins, and PPS resins are preferred.

[0060] The fixing member (c) is a member disposed between the structural member (a) and the resin structural member (b) to prevent deformation of the structural member (a) during integral molding and to prevent the resin from flowing into the internal space of the structural member (a).

[0061] The material constituting the fixing member (c) is not particularly limited, but the integrally molded article is characterized in that the fixing member (c) is in contact with both the structural member (a) and the resin structural member (b), and the softening point Tb (°C) of the resin structural member (b) and the softening point Tc (°C) of the fixing member (c) satisfy the following relationship.

[0062] Tc>Tb

[0063] The softening point here refers to the temperature at which the target material begins to deform due to a temperature rise. By satisfying this relational expression, deformation of the fixing member (c) can be suppressed.

[0064] Examples thereof include metals, resin compositions, and fiber-reinforced composite materials. From the viewpoint of processability, carbon fiber-reinforced thermoplastic resins and metals are particularly preferred.

[0065] Furthermore, from the viewpoint of suppressing deformation of the structural member (a), the glass transition temperature Ta (°C) of the structural member (a) and the softening point Tc (°C) of the fixing member (c) preferably satisfy the following relationship.

[0066] Tc>Ta

[0067] For example, in an integrated molded article obtained by inserting a structural component (a) into a mold and injection molding a structural component (b), by arranging a fixing component (c) that satisfies the relationship so as to be in contact with both the structural component (a) and the resin structural component (b), deformation can be prevented, thereby obtaining an integrated molded article with high dimensional accuracy.

[0068] Furthermore, when the fixing member (c) is a thermoplastic resin, from the viewpoint of suppressing deformation of the structural member (a) and the fixing member (c), the glass transition temperature Ta (°C) of the structural member (a), the softening point Tb (°C) of the resin structural member, and the softening point Tc (°C) of the fixing member (c) more preferably satisfy the following relationship.

[0069] 10 <Tc-Ta<180

[0070] 5 <Tc-Tb<80

[0071] The glass transition temperature is measured using differential scanning calorimetry (DSC). The DSC curve observed during the second heating process is used to separate the reversible component from the total heat flow, and the temperature (°C) at the midpoint of the step-shaped signal is used. The softening point is the temperature at which the thermoplastic resin begins to deform, and is determined using the compression load method using a thermomechanical analyzer (TMA). In the TMA curve, which is derived from the relationship between temperature and displacement, the temperature (°C) at which the displacement begins to decrease is defined as the softening point.

[0072] The molding method of the structural component (a) is not particularly limited, and it can be manufactured, for example, by autoclave molding or press molding. In particular, when the structural component (a) has a cylindrical portion, for example, it can be manufactured by the following methods: a method in which a prepreg obtained by pulling together reinforcing fibers impregnated with a thermosetting resin is wound around a core shaft while applying a predetermined tension using a filament winding method, a sheet winding method, etc., and then shaped and cured; a method in which internal pressure molding or press molding using a shaping mold is used to shape and then cured; etc. The cylindrical portion manufactured in this way is formed of a fiber-reinforced thermosetting resin having a layered structure. In the case where the thermoplastic resin layer described later is formed on the surface layer, the structural component (a) can be manufactured by the following method: finally, at least one layer of a film or non-woven fabric formed of a thermoplastic resin is wound, integrated with the thermosetting resin, and cured.

[0073] The resin structural member (b) is a member that contacts and is joined to the cylindrical portion of the structural member (a) and at least a portion of the outer or inner wall of the cylindrical portion. However, because the opening of the cylindrical portion is sealed by the fixing member (c) described later, the resin structural member (b) does not directly seal the opening of the cylindrical portion. This distinguishes it from the fixing member (c) in at least this respect.

[0074] The resin structural component (b) is preferably a joint or a base. Typically, a joint is used to connect two structural components (typically, the aforementioned structural component (a)), change the orientation of a structural component, connect structural components of different thicknesses, or merge or branch three or more structural components. A base is a component that receives and positions a structural component. Figure 1 A to C in FIG. 4 show schematic diagrams of the appearance of representative joints. Figure 2 A to C in FIG. 1 show schematic diagrams of the appearance of a representative base. Figure 3 Schematic diagrams A through E illustrate the external appearance of an integrally molded article as part of a frame structure in which structural component (a) (a tube) and a joint or base are integrated. While the respective structures are not limited to these, a frame structure using an integrally molded article in which structural component (a) is a tube and resin structural component (b) is a joint or base is a typical embodiment of the present invention.

[0075] With regard to the integrated molded article of the present invention, the resin structural component (b) capable of connection, confluence, branching, placement, etc. is firmly bonded to the lightweight, high-rigidity structural component (a), so it can be suitably used as a component forming a frame structure. As such a structure, the trunk and arm of an industrial robot, the trunk and arm of a car, motorcycle, bicycle, aircraft, helicopter, unmanned aerial vehicle, ship, submarine, etc., building materials, etc. can be cited. Especially from the viewpoint of rigidity and lightness, it can be preferably used for aircraft such as aircraft, helicopters, unmanned aerial vehicles. From the viewpoint of improving the performance of the aircraft, it is more preferably an integrated molded article with a length of the structural component (a) of more than 0.05m and less than 3m. Especially in a smaller aircraft with a main body weight of less than 1000kg, a multi-rotor aircraft equipped with more than 3 rotor wings, the influence of the weight increase brought about by mechanical fastenings such as bolts and fasteners is large, so the integrated molded article of the present invention can be particularly preferably used.

[0076] To improve mechanical properties, the resin structural component (b) preferably also contains reinforcing fibers. Examples of reinforcing fibers include the same fibers as those used in the fiber-reinforced resin constituting the structural component (a). Carbon fibers are preferred from the perspectives of lightness and mechanical properties. These reinforcing fibers may be subjected to surface treatments such as treatment with a coupling agent, treatment with a sizing agent, and treatment to attach additives.

[0077] Since the resin structural component (b) is expected to be molded into a relatively complex shape, the reinforcing fibers contained in the resin structural component (b) are preferably discontinuous reinforcing fibers from the perspective of moldability. In this case, the mass-average fiber length Lw of the reinforcing fibers is preferably 0.3 mm or greater, more preferably 0.8 mm or greater. A longer mass-average fiber length increases strength and rigidity, particularly impact strength.

[0078] Typically, the fixing component (c) is configured to cover at least a portion of the opening of the cylindrical portion of the structural component (a). The fixing component (c) is more preferably configured to face the inner cavity at the opening of the cylindrical portion and cover the opening. The presence of the fixing component (c) can prevent the resin and foreign matter from being mixed into the inner cavity of the cylindrical portion associated with the joining of the resin structural component (b) and the structural component (a). More specifically, the fixing component (c) prevents: the adhesive that overflows when the resin structural component (b) is joined with an adhesive, the molten resin when the resin structural component (b) is joined simultaneously with the molding by injection molding, etc. from intruding into the inner cavity of the cylindrical portion. Therefore, in the final integrated molded product, stable lightness and quality can be obtained.

[0079] When the fixing member (c) is arranged in contact with the end of the structural member (a), it is preferred that at least a portion of the fixing member (c) has a size greater than the inner diameter of the cylindrical portion of the structural member (a). Figure 4 B or Figure 4 With the structure shown in C in FIG, the fixing member (c) does not shift in position before and after molding, and an integrated molded product can be obtained that prevents the resin from flowing into the cylindrical portion.

[0080] From the viewpoint of achieving both lightweight and dimensional accuracy of the integrated molded article, the distance (Lc) between the following boundary surface and the end of the structural member (a) is preferably 0 to 50 mm. Figure 5 The boundary surface between the internal space in the cylindrical portion of the structural component (a) shown in A and the fixed component (c). Figure 5 If the thickness of the fixing member (c) shown in B (thickness in the radial direction of the cylindrical portion: Tc) is 0.4 to 10 mm, deformation of the fixing member (c) can be suppressed, and an integrated molded product with stable weight and dimensional accuracy can be obtained. More preferably, the following form is used: Figure 4 B or Figure 4 As shown in C, at least a portion of the fixing component (c) is engaged with the cylindrical portion of the structural component (a), that is, the entire circumference of the side surface of at least a portion of the fixing component is in contact with the entire circumference of the outer surface or inner surface of the cylindrical portion of the structural component (a), and is configured in a fixed manner.

[0081] like Figure 4 As shown in A in FIG, the fixing part (c) may also be a part that is integrally fitted with the cylindrical portion of the structural part (a), and preferably, the ratio of the opening area of ​​the structural part (a) closed by the fixing part (c) is 40 to 100%. When the closing ratio is less than 40%, there is a high possibility that the adhesive and the resin will flow into the internal space of the structural part (a). In such a manner, the area where the structural part (a) and the fixing part (c) meet is preferably 50 to 200% of the joining area between the structural part (a) and the resin structural part (b). From the viewpoint of supporting the cylindrical portion of the structural part (a) from the inner surface to the outer surface, it is more preferably 90% or more, and by making it 110% or less, the increase in the weight of the integrated molded body can be suppressed. More specifically, as Figure 4 As shown in A in FIG, in the case where the cylindrical portion of the structural component (a) is a long tube, the length of the fixing component (c) inserted into the inner cavity of the structural component from the opening surface is defined as the fitting length (L1), and the maximum length of the resin structural component (b) joined to the outer wall or inner wall of the structural component from the opening surface is defined as the joining length (L2). Figure 4As shown in A in FIG, if the fitting length L1 is equal to the joining length L2, the effect of preventing the adhesive and resin from flowing into the cylindrical interior and suppressing the deformation of the cylindrical portion caused by joining can be obtained. Figure 3 In the integrated molded product with the hollowed-out complex-shaped resin structural component (b), the joint length also becomes the length of the cylindrical portion from the opening surface to the joint end farthest away. It should be noted that the fixing component (c) is not limited to being fitted with the cylindrical portion of the structural component (a), and can also be as long as the opening of the cylindrical portion is sealed. Figure 4 The component shown in B in FIG. 1 is configured to fit only with the open end of the cylindrical portion, and the component shown in FIG. Figure 4 The part shown in C in the figure is connected to the outer wall or inner wall of the cylindrical part and is fixed, such as Figure 4 As shown in D in FIG, the components are only arranged in the cylindrical part. Figure 4 In the embodiment shown by C in FIG, the joining area between the structural member (a) and the resin structural member (b) also includes the surface joined via the fixing member (c).

[0082] The material constituting the fixing member (c) is not particularly limited. However, in order to prevent positional displacement of the fixing member (c) and to suppress deformation of the structural member (a), the linear expansion coefficient of the material constituting the fixing member (c) is preferably greater than the linear expansion coefficient of the material constituting the structural member (a). In order to achieve this effect when the fixing member (c) and the structural member (a) are fitted together, the difference between the linear expansion coefficient of the structural member (a) and the linear expansion coefficient of the fixing member (c) is preferably 2×10 -5 (1 / °C) or more, more preferably 5×10 -5 The greater the difference in linear expansion coefficient, the greater the heat transfer from the mold during molding causes the fixing member (c) to thermally expand so as to contact the inner peripheral surface of the cylindrical portion, thereby supporting the cylindrical portion by internal pressure.

[0083] The fixing member (c) is preferably substantially formed of a thermoplastic resin. The thermoplastic resin constituting the fixing member (c) is not particularly limited, and the same thermoplastic resin as that constituting the aforementioned resin structural member (b) can be used. In particular, from the perspective of the bonding strength between the resin structural member (b) and the fixing member (c), the difference in Hansen solubility parameter (HSP value) between the aforementioned resin structural member (b) and the aforementioned fixing member (c) is preferably 0 to 2 (J / cm 3 ) 1 / 2 More preferably, the difference in SP value is 1 (J / cm 3 ) 1 / 2The thermoplastic resins constituting the resin structural member (b) and the fixing member (c) are preferably homogeneous, and most preferably the same resin. Homogeneous resins herein refer to the same type of resin, and examples thereof include the case where the resins are polyolefins, polyamides, or polyesters. On the other hand, the term "the same resin" includes the case where the resins are polypropylenes, polyamide 6, and the like.

[0084] In addition, when the sealing member (c) is formed of a thermoplastic resin, from the viewpoint of quality stability, the softening point (°C) of the sealing member (c) is preferably higher than the melting point (°C) of the resin structural member (b). The melting point is measured using differential scanning calorimetry (DSC). The top temperature of the melting peak in the obtained DSC curve is set as the melting point (°C). The softening point (°C) refers to the temperature at which the above-mentioned thermoplastic resin begins to deform. As for the softening point, the compression load method using a thermomechanical analyzer (TMA) is adopted in the same manner as the above-mentioned method.

[0085] In the present invention, it is also preferred that a thermoplastic resin layer be disposed on at least a portion of the outer or inner wall of the cylindrical portion of the structural component (a), and that the resin structural component (b) be bonded to the structural component (a) via the thermoplastic resin layer. The thickness of such a thermoplastic resin layer is typically 1 to 300 μm, more preferably 50 to 150 μm. Furthermore, the form of the thermoplastic resin region is not particularly limited as long as it forms an area where the thermoplastic resin is exposed on the surface of the structural component (a). Examples thereof include layered, dotted, meshed, and lattice-like shapes.

[0086] As the thermoplastic resin used in such a thermoplastic resin layer, a resin selected from the same options as the thermoplastic resin constituting the aforementioned resin structural component (b) can be used, preferably a polyester resin, polyamide resin, polyphenylene sulfide resin, polyimide resin, polyamideimide resin, polyether ketone resin, polyether ether ketone resin, polyether ketone ketone resin, polyarylate resin, etc.

[0087] In addition, at the joint between the structural component (a) and the resin structural component (b), it is preferred that a portion of the fibers contained in the structural component (a) is in contact with a thermoplastic resin layer arranged at at least a portion of the outer wall or inner wall of the aforementioned structural component (a), or the thermoplastic resin of the resin structural component (b). By forming such a joint structure, a strong joint state can be formed by utilizing the fiber reinforcement effect. This structure can be obtained, for example, by injection-integrating the resin material of the resin structural component (b) into the following structural component (a), wherein the structural component (a) is: a structural component (a) obtained by grinding the surface layer of the structural component (a) formed of a thermosetting fiber-reinforced resin to expose the fibers, arranging a thermoplastic resin film on the exposed portion, and then press-molding again; or a structural component (a) obtained by molding a structural component (a) base material formed by laminating a thermoplastic resin film on a thermosetting resin prepreg laminate under desired temperature and pressure conditions.

[0088] The integrated molded article of the present invention can be manufactured by joining the resin structural component (b) to at least a portion of the outer wall or inner wall of the cylindrical portion of the structural component (a) while the fixing component (c) is disposed at the opening of the cylindrical portion of the structural component (a). The method for joining the resin structural component (b) is not particularly limited. For example, the structural component (b) molded separately can be joined to the cylindrical portion using an adhesive or the like. In particular, a method of joining the structural component (b) to the structural component (b) simultaneously with molding the resin structural component (b) using injection molding, i.e., insert molding or outsert molding is particularly preferred. In this case, the effect of the present invention becomes particularly significant. More specifically, it is preferred to manufacture an integrated molded article by: in a state where the structural component (a) is fixed to the mold cavity of an injection molding mold and a fixing component (c) is provided to seal the aforementioned opening of the cylindrical portion, a molten thermoplastic resin is caused to flow so as to contact at least a portion of the outer wall or inner wall of the cylindrical portion of the structural component (a), and the thermoplastic resin is solidified to thereby injection mold the resin structural component (b) and join it to the aforementioned cylindrical portion of the structural component (a).

[0089] Example

[0090] The present invention will be described in more detail below with reference to the following examples, but the present invention is not limited in any way by the description of the examples. The obtained integrated molded articles were evaluated using the following methods.

[0091] [Coefficient of variation of weight]

[0092] The weight of n=5 integrated molded articles was measured, the standard deviation (g) and the average weight (g) were determined, and the coefficient of variation of the weight was calculated using the following formula.

[0093] Coefficient of variation (%) = 100 × standard deviation (g) / average weight (g)

[0094] [Interior view after molding]

[0095] X-ray observation was performed on n=5 integrally molded parts, focusing on the joints between the structural component (a) and the resin structural component (b), as well as the fixing component (c). After cutting the integrally molded parts so that only the target portion remained, two-dimensional transmission images were captured using an X-ray inspection device (fluoroscopy) to observe the interior of the integrally molded parts. The observed images were used to evaluate the flow of resin into the cylindrical portion and the presence of deformation in the structural component (a) and the fixing component (c).

[0096] [Joined state]

[0097] A drop test was conducted on n=5 integrally molded articles, wherein the articles were dropped from a height of 1.5 m with the resin structural component (b) facing downward. The bonding state between the structural component (a) and the resin structural component (b) at this time was visually observed, and the aforementioned X-ray fluoroscopy was performed again to evaluate the presence of cracks at the bonding portion between the structural component (a) and the resin structural component (b), and at the bonding portion between the resin structural component (b) and the fixing component (c).

[0098] (Example 1)

[0099] On a mold-released stainless steel mandrel with a tip outer diameter of 30 mm and a length of 700 mm, Toray Industries, Inc.'s "Torayca Prepreg" P3051S-30 and P3052S-12 were laminated, with the fiber-reinforced resin P3051S-30 having a material angle of 0 degrees and the fiber-reinforced resin P3052S-12 having a material angle of 60 degrees, with the mandrel's longitudinal direction set at the 0-degree axis. Furthermore, a 70 μm thick polyamide film, obtained by hot-pressing pellets of a copolyamide resin (CM4000 manufactured by Toray, polyamide 6 / 66 / 610, melting point 150°C), was wrapped around the outer surface for one full turn. A wrapping tape (heat-resistant film tape, 10 mm wide) was then wrapped at a tension of 3 kg, and the film was heat-molded in a curing oven at 150°C for 30 minutes. After that, the mandrel is pulled out, the wrapping tape is removed, and then the tube is cut to obtain a tube (structural component (a)) with a thickness of 0.5 mm and a length of 500 mm. Next, a resin block (fixing component (c)) with an outer diameter of 30 mm and a thickness of 30 mm obtained by injection molding polyamide 66 resin (Amiran CM3001N manufactured by Toray) pellets is embedded in the tube and the opening of the tube is sealed, and it is confirmed that the end face of the tube opening is consistent with the end face of the resin block. Then, the outer periphery of the tube is clamped with a clamp provided on the outside of the injection molding mold, and after adjusting the tube opening face to the desired position in the mold cavity, the tube is embedded in the injection molding mold. Using an injection molding machine (J350EIII manufactured by Nippon Steel Works) set to a barrel temperature of 280°C and a mold temperature of 80°C, the long fiber pellets (TLP1060 manufactured by Toray Industries, Ltd.) are inserted in such a way that an area 30 mm from the end of the outer peripheral surface of the tube contacts its inner peripheral surface. Figure 2 The base (resin structural member (b)) of the shape shown in A is injection molded to produce Figure 3 An integrated molded product having the shape shown by C in FIG.

[0100] The coefficient of variation in weight for the five resulting integrated molded products remained stable at 0.9%. Furthermore, X-ray transmission images revealed no inflow of injected resin into the tubes, nor any deformation of the tubes or resin mass. Furthermore, a drop test, in which the tubes were dropped from a height of 1.5 meters with the joint facing downward and the joint-to-joint bond was subsequently confirmed, revealed no changes in the joints, indicating a well-maintained bond.

[0101] (Example 2)

[0102] A tube (structural component (a)) is prepared in the same manner as in Example 1. Next, a resin plate (fixing component (c)) having an outer diameter of 32 mm and a thickness of 3 mm obtained by injection molding polyamide 66 resin (Amiran CM3001N manufactured by Toray Industries, Ltd.) pellets is arranged so as to face the opening surface of the tube, and then a soldering iron heated to 300°C is used to heat the resin plate near the outer edge of the tube to melt it, so that it is fixed to the tube and the opening of the tube is sealed. Then, the outer periphery of the tube is clamped with a clamp provided on the outside of the injection molding mold, and after adjusting the outermost surface of the resin plate fixed to the opening surface of the tube to the desired position in the mold cavity, the tube is embedded in the injection molding mold. Using an injection molding machine (J350EIII manufactured by Nippon Steel Works, Ltd.) set to a barrel temperature of 280°C and a mold temperature of 80°C, the long fiber pellets (TLP1060 manufactured by Toray Industries, Ltd.) are fixed so that an area 30 mm from the end of the outer peripheral surface of the tube contacts its inner peripheral surface. Figure 2 The base (resin structural member (b)) of the shape shown in A is injection molded to produce Figure 3 An integrated molded product having the shape shown by C in FIG.

[0103] Regarding the obtained integrated molded products n=5, the coefficient of variation of the weight became 5.6%, which is a result with a large deviation compared with Example 1. In addition, although the flow of the injected resin into the inside of the tube was not confirmed based on the X-ray transmission image, the resin plate used as the fixing component was bent in all samples. However, no gap was confirmed between the fixing component and the resin structural component (joint). In addition, slight deformation was also confirmed in the cylindrical part of the structural component. In addition, these tubes were subjected to a drop test in which they were dropped from a height of 1.5m with the joint facing downward and the subsequent joining state of the tube and the joint was confirmed. As a result, no changes were observed in the joints of the five tubes, and a good joining state was maintained.

[0104] (Example 3)

[0105] A tube (structural component (a)) is obtained in the same manner as in Example 1. Next, an aluminum block (fixing component (c)) having an outer diameter of 30 mm and a thickness of 30 mm obtained by lathing an aluminum alloy is embedded in the tube and the opening of the tube is sealed, and it is confirmed that the end face of the tube opening is consistent with the end face of the aluminum block. Then, the outer periphery of the tube is clamped with a clamp provided on the outside of the injection molding mold, and after adjusting the tube opening face to the desired position in the mold cavity, the tube is embedded in the injection molding mold. Using an injection molding machine (J350EIII manufactured by Nippon Steel Works) set at a barrel temperature of 280°C and a mold temperature of 80°C, the long fiber pellets (TLP1060) manufactured by Toray Industries, Ltd. are placed in such a manner that an area of ​​30 mm from the end of the outer peripheral surface of the tube contacts its inner peripheral surface. Figure 2The base (resin structural member (b)) of the shape shown in A is injection molded to produce Figure 3 An integrated molded product having the shape shown by C in FIG.

[0106] The coefficient of variation in weight for the resulting five integrated molded articles was 1.0%, comparable to that of Example 1. Furthermore, X-ray transmission images revealed no inflow of the injected resin into the tubes, nor any deformation of the tubes or resin blocks. Furthermore, a drop test, in which the tubes were dropped from a height of 1.5 meters with the joint facing downward and the joint-to-joint bond observed, revealed cracks between the aluminum block and the joint in two of the five samples. However, no cracks were observed at the joint between the tube and joint.

[0107] (Example 4)

[0108] Toray Industries, Inc.'s "Torayca Prepreg" P3051S-30 and P3052S-12 were laminated, with the fiber-reinforced resin P3051S-30 at a 0-degree material angle and the fiber-reinforced resin P3052S-12 at a 60-degree material angle. Furthermore, a layer of a 70-μm-thick polyamide film, obtained by hot-pressing pellets of a copolyamide resin (CM4000, manufactured by Toray Industries, Inc., polyamide 6 / 66 / 610, melting point 150°C), was laminated on top. Heat molding was then performed for 30 minutes at a mold temperature of 150°C and a molding pressure of 0.5 MPa. After demolding, the film was cut to obtain a flat plate (structural component (a)) with a thickness of 1.5 mm, a length of 300 mm, and a width of 25 mm. Next, the following resin block (fixing component (c)) is fitted into one end of the flat plate. The resin block is obtained by injection molding polyamide 66 resin (Toray Amiran CM3001N) pellets, has a thickness of 3.5mm, a length of 82mm, a width of 27mm, and is open at one end. Inside, it has a hollow portion with a thickness of 1.5mm, a length of 80mm, and a width of 25mm. Then, the outer periphery of the flat plate is clamped with a clamp provided on the outside of the injection molding mold. After adjusting it to the desired position within the mold cavity, the flat plate is embedded in the injection molding mold. Using an injection molding machine (J350EIII manufactured by Japan Steel Works) set at a barrel temperature of 280°C and a mold temperature of 80°C, a joint (resin structural component (b)) is injection molded into a region 80mm from the end face of the flat plate where the resin block is arranged, thereby producing an integrated molded product.

[0109] The coefficient of variation in weight for the resulting five integrated molded articles was comparable to that of Example 1, and no deformation of the flat plate was observed. Furthermore, when these integrated molded articles were dropped from a height of 1.5 m with the joint facing downward, no cracks were observed at the junction between the flat plate and the joint.

[0110] (Comparative Example 1)

[0111] A tube (structural component (a)) was obtained in the same manner as in Example 1. Next, the outer periphery of the tube was clamped with a clamp provided on the outside of the injection molding mold, the tube opening was adjusted to the desired position in the mold cavity, and the tube was inserted into the injection molding mold. Using an injection molding machine (J350EIII manufactured by Japan Steel Works) set at a barrel temperature of 280°C and a mold temperature of 80°C, a long fiber pellet (TLP1060 manufactured by Toray Industries, Ltd.) was placed in a manner such that a region of 30 mm from the end of the outer periphery of the tube was in contact with the inner periphery. Figure 2 The base (resin structural member (b)) of the shape shown in A is injection molded to produce Figure 3 An integrated molded product having the shape shown by C in FIG.

[0112] For the resulting integrated molded articles (n=5), the injected resin flowed into the tubes (structural component (a)), preventing the joints (resin structural component (b)) from being formed. Evaluation of the coefficient of variation in weight was not performed, but X-ray transmission images revealed accumulation of injected resin within the tubes. Furthermore, since the joints could not be joined within a 30 mm area from the outer circumference of the tubes, the drop test could not be evaluated.

[0113] (Comparative Example 2)

[0114] The same procedures as in Example 4 were followed to produce a flat plate (structural component (a)) with a thickness of 1.5 mm, a length of 300 mm, and a width of 25 mm. Subsequently, the outer periphery of the flat plate was clamped with a fixture provided on the outside of the injection molding mold, adjusted to the desired position within the mold cavity, and then inserted into the injection molding mold. Using an injection molding machine (J350EIII manufactured by The Japan Steel Works, Ltd.) set at a cylinder temperature of 280°C and a mold temperature of 80°C, a joint (resin structural component (b)) was injection molded using Toray Industries, Ltd. long-fiber pellets (TLP1060) in an area 80 mm from the end face of the flat plate where the resin block was located, producing an integrated molded product.

[0115] For the five integrally molded parts obtained, the resin flow formed burrs at the integrally molded ends, and the coefficient of variation in weight was not evaluated. X-ray transmission images confirmed deformation of the flat plate (structural component (a)) due to the inflow of injected resin. This deformation is believed to have created a gap between the plate and the mold, leading to the burrs.

[0116] (Summarize)

[0117] In Example 1, the coefficient of variation in the weight of the integrated molded article was small, indicating stable results. This is believed to be because Example 1 achieved bonding without excess resin flowing into the inner cavity of the cylindrical portion. On the other hand, in Comparative Example 1, which lacked a fixing member, the injected resin flowed through the tube opening, preventing the desired integrated molded article from being obtained.

[0118] Furthermore, compared to Example 2, Example 1 exhibited a superior internal appearance after molding. This is because, in Example 2, while the fixing component faced the opening, it was not engaged with the tubular portion. Consequently, injection pressure during insert molding caused the fixing component to flex and the tube to deform. This is believed to be due to the injection resin filling these flexed and deformed areas, leading to a poorer coefficient of variation in the weight of the integrated molded product compared to Example 1.

[0119] Furthermore, Example 1 showed higher bonding strength of the integrally molded article compared to Example 3. This is believed to be because, in Example 3, the resin structural component and the aluminum alloy used in the fixing component had low compatibility, resulting in easy separation between the resin structural component and the fixing component during the drop test.

[0120] In Example 4, which is an integrally molded article with a flat plate, the generation of burrs is suppressed, and the integrally molded article exhibits an excellent appearance, compared to Comparative Example 2. This is believed to be because, in Comparative Example 2, the flat plate deforms due to the heat of the injected resin, creating a gap at the contact point between the mold and the flat plate, allowing the injected resin to flow.

[0121] Industrial applicability

[0122] The integrated molded article of the present invention can be suitably used as a component forming a frame structure. Examples of such structures include the trunk and arms of industrial robots, the trunks and arms of automobiles, motorcycles, bicycles, aircraft, helicopters, drones, ships, submarines, and architectural structures.

[0123] Description of Reference Numerals

[0124] 1 Structural components (a)

[0125] 2 Resin structural parts (b)

[0126] 3 Fixing parts (c)

[0127] L1 mating length

[0128] L2 joint length

[0129] 4 Internal space in the cylindrical portion of the structural component (a)

[0130] 5 Boundary surface

[0131] Lc is the distance between the boundary surface and the end of the structural component (a)

[0132] Tc is the thickness of the fixing member (c) in the vertical direction relative to the outer wall or inner wall where the structural member (a) and the fixing member (c) meet.

Claims

1. An integrally molded article comprising a structural component (a), a resin structural component (b), and a fixing component (c), wherein: The fixing member (c) is in contact with both the structural member (a) and the resin structural member (b). The softening point Tb (°C) of the resin structural member (b) and the softening point Tc (°C) of the fixing member (c) satisfy the following relationship: Tc>Tb.

2. The integrated molded article according to claim 1, wherein: The glass transition temperature Ta (° C.) of the structural member (a) and the softening point Tc (° C.) of the fixing member (c) satisfy the following relationship, Tc>Ta.

3. The integrally molded article according to claim 2, wherein: The glass transition temperature Ta (°C) of the structural member (a), the softening point Tb (°C) of the resin structural member (b), and the softening point Tc (°C) of the fixing member (c) satisfy the following relationship: 10 <Tc-Ta<180 5 <Tc-Tb<80。 4. The integrally molded article according to claim 1, wherein: The structural member (a) is a structural member having an internal space, and the structural member (a) and the resin structural member (b) are in contact and joined at least partially.

5. The integrally molded article according to claim 1, wherein: The structural member (a) is a structural member having an open internal space, and the fixing member (c) is a member that covers at least a portion of the opening of the structural member (a).

6. The integrally molded article according to claim 1, wherein: The structural component (a) is a structural component having an open cylindrical portion, and the cylindrical portion of the structural component (a) and the resin structural component (b) are in contact and joined at least partially at an outer wall or an inner wall of the cylindrical portion.

7. The integrally molded article according to claim 6, wherein: The cylindrical portion of the structural member (a) and the resin structural member (b) are joined via a thermoplastic resin at at least a portion of an outer wall or an inner wall of the cylindrical portion.

8. The integrally molded article according to claim 6, wherein: The structural member (a) is substantially formed of a carbon fiber reinforced thermosetting resin, A thermoplastic resin layer is arranged on at least a portion of the outer wall or inner wall of the structural component (a), the resin structural component (b) is an injection-molded body, the structural component (a) and the resin structural component (b) are joined via the thermoplastic resin layer of the structural component (a), and at least a portion of the opening of the structural component (a) is covered by the fixing component (c).

9. The integrally molded article according to claim 8, wherein: The resin structural member (b) is formed of a carbon fiber reinforced thermoplastic resin, and the fixing member (c) is formed of a material having a linear expansion coefficient larger than that of a material constituting the structural member (a).

10. The integrally molded article according to claim 8, wherein: The resin structural member (b) is formed of a carbon fiber reinforced thermoplastic resin, and the fixing member (c) is formed of a carbon fiber reinforced thermoplastic resin or metal.

11. The integrally molded article according to claim 8, wherein: The resin structural component (b) is formed of a carbon fiber reinforced thermoplastic resin, the fixing component (c) is formed of a carbon fiber reinforced thermoplastic resin having a softening point (°C) higher than the melting point (°C) of the resin structural component (b), and the fixing component (c) is present between the internal space of the structural component (a) and the resin structural component (b).

12. The integrally molded article according to claim 6, wherein: At least a portion of the fixing member (c) has a size equal to or larger than the inner diameter of the cylindrical portion of the structural member (a).

13. The integrally molded article according to claim 6, wherein: The distance between the boundary surface between the internal space in the cylindrical portion of the structural member (a) and the fixing member (c) and the end portion of the structural member (a) is 0 to 50 mm.

14. The integrally molded article according to claim 1, wherein: The thickness of the fixing component (c) is 0.4 to 10 mm.

15. The integrally molded article according to claim 6, wherein: The ratio of the opening area of ​​the structural component (a) closed by the fixing component (c) is 40 to 100%.

16. The integrally molded article according to claim 6, wherein: The area (L1) where the structural member (a) and the fixing member (c) are in contact is 50 to 200% of the area (L2) where the structural member (a) and the resin structural member (b) are joined.

17. The integrally molded article according to claim 1, wherein: The fixing member (c) is substantially formed of a thermoplastic resin, and the difference in Hansen solubility parameter (HSP value) between the resin structural member (b) and the fixing member (c) is 0 to 2 (J / cm 3 ) 1 / 2 .

18. The integrally molded article according to claim 6, wherein: The structural component (a) is a pipe, and the resin structural component (b) is a joint or a base.

19. A frame structure formed by using the integrally molded article according to claim 18.

20. An aircraft produced by using the integrally molded article according to claim 18.

21. The aircraft of claim 20, wherein: The length of the structural member (a) is not less than 0.05 m and not more than 3 m.

22. The aircraft according to claim 20, wherein the main body weight is less than 1000 kg.

23. The aircraft according to claim 20, which is a multi-rotor type equipped with three or more rotors.

24. A method for manufacturing an integrally molded article, wherein: In a state where a fixing member (c) is arranged on a structural member (a) having a cylindrical portion substantially formed of a fiber-reinforced resin with an opening at least at one end thereof and covering the opening of the cylindrical portion, a resin structural member (b) is joined so as to be in contact with at least a portion of the outer wall or inner wall of the cylindrical portion of the structural member (a).

25. The method for manufacturing an integrally molded article according to claim 24, wherein: With the structural component (a) fixed to the cavity of an injection molding mold and a fixing component (c) arranged to cover the opening of the cylindrical portion, molten thermoplastic resin is caused to flow in contact with at least a portion of the outer wall or inner wall of the cylindrical portion of the structural component (a), and the thermoplastic resin is solidified while applying a holding pressure, thereby injection molding the resin structural component (b) and joining it to the cylindrical portion of the structural component (a).

Images