Rotating electric machine protective ring manufacturing method, rotating electric machine, and electrically-driven mobility equipment

Abstract

The purpose of the present invention is to provide a rotating electric machine protective ring manufacturing method which is capable of inhibiting exudation of a resin composition and thread breakage in a material traveling step during manufacturing a rotating electric machine protective ring which comprises a fiber reinforced composite material and is formed by being wound around the outer side of a rotor in a rotating electric machine. The present invention involves: applying a tensile stress P of 300-4000 MPa to a material containing a resin composition and a reinforced fiber bundle from a certain point in a traveling path of the material; and, when the temperature of the material during the period in which the tensile stress P is applied is defined as T, and the glass transition temperature of the resin composition contained in the material is defined as Tg, providing, to the path in which the tensile stress P is applied, a region in which the difference ΔT between T and Tg represented by equation (I) satisfies ΔT<30°C. (I): ΔT=T-Tg

Description

Method for manufacturing a protective ring for a rotating electric machine, a rotating electric machine, and an electric mobility device

[0001] The present invention relates to a method for manufacturing a protective ring for a rotating electric machine that can be used to protect the rotor of a rotating electric machine such as a generator or an electric motor, a rotating electric machine, and an electric mobility device.

[0002] In recent years, there has been a demand for higher speeds of rotating electrical machines to improve their performance. Rotating electrical machines include SPM (Surface Permanent Magnet) types in which permanent magnets are arranged on the outer periphery of the rotor, and IPM (Internal Permanent Magnet) types in which permanent magnets are arranged embedded in the rotor. However, when such rotating electrical machines are rotated at high speeds, centrifugal force can cause the outer periphery permanent magnets to fall off the rotor, or the fallen permanent magnets can interfere with the stator arranged on the outer periphery of the rotor, resulting in damage to the rotor itself.

[0003] To prevent damage and deformation of rotating electrical machines due to such high-speed rotation, Patent Document 1 describes a motor rotor that includes a thread-wound layer formed by winding threads made of a reinforced fiber material around a permanent magnet, impregnated with a thermosetting resin composition, and equipped with a cylindrical body that covers the surface of the thread-wound layer from the radial outside of the rotating shaft. It also describes that it is preferable to wind the thread-wound layer with tension (e.g., 3 kgf (approximately 29 N) or more) to prevent the thread from unraveling.

[0004] Patent Document 2 describes a resistance imparting device used in the manufacture of pressure vessels, as well as a filament holding device, a filament winding device, and a filament winding method using the same. The resistance imparting device winds the filament around the outer periphery of a friction resistance imparting member, and describes a method in which the filament is fed out while a large tension is applied to the filament and wound around a workpiece (core).

[0005] Patent Document 3 describes a rotor composed of a permanent magnet and a shatter prevention member attached along its outer surface, and states that the clamping force of the shatter prevention member must be greater than the centrifugal force of the permanent magnet, and that this clamping force can suppress deformation of the permanent magnet toward the outer diameter. Furthermore, this shatter prevention member is made by applying high tension (e.g., 250 to 500 N) to a ribbon-shaped CFRP material, winding it around the rotor, and then subjecting it to a heat-hardening process.

[0006] International Publication No. 2008 / 047767 Japanese Patent Application Laid-Open No. 2005-238688 Japanese Patent Application Laid-Open No. 2023-151124

[0007] In the invention described in Patent Document 1, the permanent magnet is held by the cylindrical body, so there is no need to apply high tension to the ring (the reinforcing fiber material that constitutes the yarn wound layer), but on the other hand, it is necessary to fix the cylindrical body to the annular member by shrink fitting. If tension sufficient to hold the permanent magnet is applied without the cylindrical body, the filament traveling through the yarn path will not be able to withstand the tension and will break, but there is no description of a process design to address this.

[0008] In the invention described in Patent Document 2, the winding of the filament in a general pressure vessel is about 5 kg / mm ２ (approximately 49 MPa), which is 15 kg / mm ２ A high tension (approximately 147 MPa) is applied to the yarn. However, this tension is insufficient to hold the permanent magnet when the motor rotor rotates at high speed, resulting in a problem of reduced rotation speed. Furthermore, there is no description of process design from the perspective of reducing yarn breakage when applying high tension.

[0009] In the invention described in Patent Document 3, in order to suppress deformation of the outer diameter side of the permanent magnet, CFRP material is wound around the rotor under high tension. However, as in Patent Documents 1 and 2, there is no description of the design of materials or processes to reduce thread breakage when high tension is applied.

[0010] The present invention aims to improve upon the drawbacks of the conventional technology by discovering that when manufacturing a rotating electric machine protective ring by winding a material containing a resin composition and a reinforced fiber bundle around the outside of the rotor of a rotating electric machine, there is a problem in winding the material around the rotor with a tension above a certain level. The present invention aims to provide a method for manufacturing a rotating electric machine protective ring that allows the material to be wound around the rotor normally even with high tension, suppresses displacement that occurs during operation, and ultimately enables an improvement in the individual output density of the rotating electric machine, as well as a rotating electric machine and electric mobility equipment that have a rotating electric machine protective ring obtained by such a manufacturing method.

[0011] As a result of intensive research aimed at solving the above-mentioned problems, the present inventors have discovered a method for manufacturing a rotating electric machine protection ring having any of the following configurations, and a rotating electric machine and an electric mobility device having a rotating electric machine protection ring obtained by such a manufacturing method, and have completed the present invention. (1) A method for manufacturing a rotating electric machine protection ring, comprising applying a tensile stress to a material containing a resin composition and a reinforcing fiber bundle, causing the material to travel along a predetermined path, and then winding the material into an annular shape a plurality of times to form a cylindrical laminate, wherein a tensile stress P of 300 MPa or more and 4000 MPa or less is applied to the material from a certain point on the path, and the path along which the tensile stress P is applied has a region in which a difference ΔT between T and Tg, expressed by the following formula (I), satisfies ΔT<30°C, where T is the temperature of the material during the application of the tensile stress P and Tg is the glass transition temperature of the resin composition contained in the material. (I) ΔT=T−Tg (2) The method for manufacturing a protection ring for a rotating electric machine according to (1) above, wherein the tensile stress P is in the range of 300 MPa or more and 3300 MPa or less. (3) The method for manufacturing a protection ring for a rotating electric machine according to (1) above, wherein the tensile stress P is in the range of 300 MPa or more and 2700 MPa or less. (4) The method for manufacturing a protection ring for a rotating electric machine according to any one of (1) to (3) above, wherein ΔT<30°C is satisfied over the entire path in which the tensile stress P is applied. (5) While the tensile stress P is applied, the complex viscosity of the resin composition contained in the material is 10 ４ Pa・s or more 10 ８(6) A method for manufacturing a protection ring for a rotating electric machine according to any one of (1) to (4), wherein the tensile stress P is Pa·s or less. (7) A method for manufacturing a protection ring for a rotating electric machine according to any one of (1) to (5), comprising a stress applying step of increasing the tensile stress P to a desired value. (8) A method for manufacturing a protection ring for a rotating electric machine according to claim 6, wherein at least a portion of the material is cooled to 20°C or less before and / or during the stress applying step. (9) A rotating electric machine having a rotor and a protection ring for a rotating electric machine, wherein the protection ring is formed by winding a material containing a resin composition and a reinforced fiber bundle annularly around the rotor multiple times and forming it into a cylindrical laminate having an outer diameter of 6 cm or more and 23 cm or less, and wherein a rate of change of the outer diameter when operated at a rotation speed of 10,000 rpm is 0.1% or less. (10) A rotating electric machine according to (8), wherein the unit power density is 8 kW / kg or more. (10) An electric mobility device equipped with the rotating electric machine described in (9) above.

[0012] In the manufacturing method of the rotating electric machine protection ring of the present invention, a predetermined tensile stress P is applied to a material containing a resin composition and reinforcing fiber bundles to form a cylindrical laminate, and by controlling the relationship between the temperature T of the material while the tensile stress P is being applied and the glass transition temperature Tg of the resin composition contained in the material, it is possible to apply the required high tensile stress, and by applying a tensile stress above a certain level, it is possible to suppress thread breakage that occurs during the running process of the material.

[0013] Furthermore, in the present invention, by setting the tensile stress P within a more preferable range, it is possible to suppress not only thread breakage but also squeezing and seeping out of the resin composition during the running process, including the path leading up to the start of winding the material. That is, when a tape-shaped material is generally unwound from a bobbin such as a cardboard tube, even if a certain tension is applied, even if it is not high tension, a phenomenon in which the resin composition is squeezed out of the tape-shaped material can occur. This phenomenon tends to result in a higher resin composition content in the tape-shaped material located on the outer periphery than in the tape-shaped material located on the bobbin side. Furthermore, for example, if a certain tension is applied to the tape-shaped material when it enters a stress-applying mechanism (described below) installed in the running path, the tape-shaped material is pressed against a jig constituting the mechanism, resulting in seeping out of the resin composition. Therefore, the resin composition content of the tape-shaped material is likely to vary immediately before being wound around the rotating electrical machine protection ring. Thus, if the resin composition content within the tape-shaped material varies greatly or the content becomes unstable, this can cause uneven thickness or variations in physical properties when the tape-shaped material is wrapped around a rotor or the like and heat-cured to produce a protective ring for a rotating electric machine. However, in the present invention, by setting the tensile stress P within a more preferred range and controlling the relationship between the temperature T of the material while the tensile stress P is being applied and the glass transition temperature Tg of the resin composition contained in the material, it is possible to suppress the above-mentioned phenomenon and reduce unevenness in the resin composition content within the tape-shaped material.

[0014] Furthermore, the rotating electric machine protection ring obtained by the present invention suppresses ring displacement during operation of the rotating electric machine, thereby further improving the individual power density of rotating electric machines and electric mobility devices equipped with rotating electric machines.

[0015] 1 is a perspective view of a rotating electrical machine protection ring according to an embodiment of the present invention; FIG. 2 is a schematic view of a manufacturing device for a rotating electrical machine protection ring according to an embodiment of the present invention; FIG. 3 is a schematic view of a manufacturing device for a rotating electrical machine protection ring provided with a cooling mechanism according to an embodiment of the present invention;

[0016] (Configuration of the Rotating Electric Machine Protection Ring) As shown in FIG. 1 , the rotating electric machine protection ring of the present invention is formed by winding a material containing a resin composition and reinforcing fiber bundles multiple times around a core 3, which is a component to be ultimately fastened, such as a rotor of a rotating electric machine, and molding the ring into a cylindrical laminate 1. The material containing a resin composition and reinforcing fiber bundles (hereinafter sometimes referred to as a "fiber-reinforced composite material" or simply "material") may be a tape-shaped material in which the reinforcing fibers are impregnated with the resin composition. The tape-shaped material may be wound continuously from the beginning to the end of winding, or may be wound intermittently in multiple steps. In the present invention, the laminate 1 may refer to the state after the fiber-reinforced composite material is wound, stacked, and further molded, or the state in which the fiber-reinforced composite material is simply wound and stacked, i.e., the state in the manufacturing process before molding. Furthermore, the term "cylindrical shape" is not limited to a cylindrical body with a perfectly circular cross section, but also includes those having minute irregularities on the surface due to the reinforcing fiber bundles, etc.

[0017] The type of the reinforcing fiber bundle is not particularly limited, and glass fiber, carbon fiber, aramid fiber, boron fiber, alumina fiber, silicon carbide fiber, etc. can be used. Two or more of these fibers may be mixed. From the viewpoint of obtaining a lightweight and highly rigid fiber-reinforced composite material, it is preferable to use carbon fiber. The number of fibers constituting the fiber bundle can be, for example, 1,000 to 50,000. The strand strength, which is the strength of the carbon fiber bundle, is preferably 4,000 MPa or more. There is no upper limit, but carbon fibers of 8,000 MPa or less can be used. A method for measuring strand strength will be described later in the examples.

[0018] The resin composition used in the fiber-reinforced composite material is not particularly limited, and thermosetting resins such as epoxy resins, unsaturated polyester resins, phenolic resins, vinyl ester resins, and cyanate ester resins can be used in an uncured state. Two or more of these resins may also be mixed and used.

[0019] When an epoxy resin composition is used in the resin composition of the present invention, it is preferable that the resin composition contains the following components [A] and [B] as essential components. Component [C] is not essential, but is preferably included when adjusting the tackiness and complex viscosity of the resin composition. In the present invention, "component" refers to a compound contained in the composition. Component [A]: epoxy resin Component [B]: curing agent that reacts with component [A] Component [C]: thermoplastic resin.

[0020] Examples of the component [A] include epoxy resins such as diaminodiphenylmethane type, diaminodiphenyl sulfone type, aminophenol type, bisphenol type, metaxylenediamine type, 1,3-bisaminomethylcyclohexane type, isocyanurate type, hydantoin type, phenol novolac type, orthocresol novolac type, dicyclopentadiene type, trishydroxyphenylmethane type, and tetraphenylolethane type.

[0021] Commercially available diaminodiphenylmethane epoxy resins include ELM434 (manufactured by Sumitomo Chemical Co., Ltd.), ELM434VL (manufactured by Sumitomo Chemical Co., Ltd.), Araldite (registered trademark) MY720 (manufactured by Huntsman Advanced Materials Co., Ltd.), Araldite (registered trademark) MY721 (manufactured by Huntsman Advanced Materials Co., Ltd.), Araldite (registered trademark) MY9512 (manufactured by Huntsman Advanced Materials Co., Ltd.), Araldite (registered trademark) MY9663 (manufactured by Huntsman Advanced Materials Co., Ltd.), and Epotohto (registered trademark) YH-434 (manufactured by Nippon Steel Chemical & Material Co., Ltd.).

[0022] Commercially available diaminodiphenyl sulfone type epoxy resins include TG3DAS (manufactured by Mitsui Fine Chemicals, Inc.).

[0023] Commercially available aminophenol-type epoxy resins include ELM120 (manufactured by Sumitomo Chemical Co., Ltd.), ELM100 (manufactured by Sumitomo Chemical Co., Ltd.), jER (registered trademark) 630 (manufactured by Mitsubishi Chemical Corporation), Araldite (registered trademark) MY0500 (manufactured by Huntsman Advanced Materials Co., Ltd.), Araldite (registered trademark) MY0510 (manufactured by Huntsman Advanced Materials Co., Ltd.), Araldite (registered trademark) MY0600 (manufactured by Huntsman Advanced Materials Co., Ltd.), and Araldite (registered trademark) MY0610 (manufactured by Huntsman Advanced Materials Co., Ltd.).

[0024] The bisphenol type epoxy resins include bisphenol A type epoxy resins and bisphenol F type epoxy resins.

[0025] Commercially available bisphenol A epoxy resins include jER (registered trademark) 825 (manufactured by Mitsubishi Chemical Corporation), jER (registered trademark) 828 (manufactured by Mitsubishi Chemical Corporation), Epiclon (registered trademark) 850 (manufactured by DIC Corporation), Epotohto (registered trademark) YD-128 (manufactured by Tohto Kasei Co., Ltd.), DER-331 (manufactured by The Dow Chemical Company), and DER-332 (manufactured by The Dow Chemical Company).

[0026] Commercially available bisphenol F epoxy resins include Araldite (registered trademark) GY282 (manufactured by Huntsman Advanced Materials), jER (registered trademark) 806, jER (registered trademark) 807, and jER (registered trademark) 1750 (all manufactured by Mitsubishi Chemical Corporation), Epiclon (registered trademark) 830 (manufactured by DIC Corporation), and Epotohto (registered trademark) YD-170 (manufactured by Tohto Kasei Co., Ltd.).

[0027] In the present invention, the epoxy resin composition may also contain epoxy compounds other than those mentioned above.

[0028] Examples of component [B] include amine-based curing agents, alcohol compounds, phenolic compounds, cationic curing agents, anionic curing agents, radical curing agents, acid anhydride compounds, and imidazole compounds. Examples of amine-based curing agents include dicyandiamide or its derivatives, and diaminodiphenyl sulfone or its derivatives. Dicyandiamide can be used in combination with a urea amine-based curing agent or a urea compound to control the reactivity of the curing reaction induced by the dicyandiamide. Because these curing accelerators containing urea compounds react with component [A], they are considered curing agents in the present invention and are included in the examples of component [B]. Examples of urea compounds include 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU99), 3-(4-chlorophenyl)-1,1-dimethylurea, phenyldimethylurea, and toluenebisdimethylurea.

[0029] Commercially available dicyandiamide products include DICY-7 and DICY-15 (both manufactured by Mitsubishi Chemical Corporation). Diaminodiphenyl sulfone has structural isomers depending on the position of the amino group. Commercially available 4,4'-diaminodiphenyl sulfone products include "Seikakyuka (registered trademark)"-S (manufactured by Wakayama Seika Kogyo Co., Ltd.) and "Sumicure (registered trademark)" S (manufactured by Sumitomo Chemical Co., Ltd.). Commercially available 3,3'-diaminodiphenyl sulfone products include 3,3'-DAS (manufactured by Mitsui Chemicals Fine Co., Ltd.).

[0030] Examples of component [C] include polyamide, polycarbonate, polyacetal, polyphenylene oxide, polyphenylene sulfide, polyarylate, polyester, polyamideimide, polyimide, polyetherimide, polyimide having a phenyltrimethylindane structure, polysulfone, polyethersulfone, polyetherketone, polyetheretherketone, polyaramid, polyethernitrile, and polybenzimidazole, polyvinyl alcohol, polyvinyl acetal, polyvinyl formal, polyvinyl acetoacetal, polyvinyl butyral, polyvinyl acetate, hydrogenated bisphenol A-pentaerythritol phosphite polymer, hydrogenated terpene, and hydrogenated terpene phenol.

[0031] Commercially available products of the component [C] (thermoplastic resin) include, for example, commercially available polyethersulfone products such as "Sumikaexcel (registered trademark)" PES3600P, "Sumikaexcel (registered trademark)" PES5003P, "Sumikaexcel (registered trademark)" PES5200P, and "Sumikaexcel (registered trademark)" PES7600P (all manufactured by Sumitomo Chemical Co., Ltd.), and "VIRANTAGE (registered trademark)" VW-10700RFP (manufactured by Solvay Advanced Polymers, Inc.), as well as commercially available copolymer oligomers of polyethersulfone and polyetherethersulfone, and polyetherimide. Examples of suitable thermoplastic resins include "Ultem (registered trademark)" 1000, "Ultem (registered trademark)" 1010, and "Ultem (registered trademark)" 1040 (all manufactured by SABIC Innovative Plastics), and other thermoplastic resins include "J-POVAL (registered trademark)" (manufactured by Japan Vinyl Acetate & Poval Co., Ltd.), "Vinylec (registered trademark)" (manufactured by JNC Corporation), "S-LEC (registered trademark)" (manufactured by Sekisui Chemical Co., Ltd.), "Ultrasene (registered trademark)" (manufactured by Tosoh Corporation), JPH-3800 (manufactured by Johoku Chemical Industry Co., Ltd.), and YS Polystar UH130 (manufactured by Yasuhara Chemical Co., Ltd.).

[0032] The rotating electrical machine protection ring of the present invention is preferably configured by a laminate 1 formed by winding a tape-shaped material, which is made by impregnating a reinforcing fiber bundle with a resin composition, into a circular shape a plurality of times.

[0033] Such tape-shaped material may be a prepreg slit tape or towpreg in which a reinforcing fiber bundle has been previously impregnated with a resin composition, or may be a material in which a reinforcing fiber bundle has been impregnated with a resin composition during the manufacturing process of the laminate 1 by a method such as filament winding.

[0034] There are no particular restrictions on the width of the tape-shaped material, but it is preferable to use one with a width of 1 mm to 20 mm, as this makes it easier to wind the material to form a laminate.

[0035] The rotating electrical machine protection ring of the present invention preferably has an outer diameter (reference numeral 10 in FIG. 1) of 1 cm to 25 cm, more preferably 6 to 23 cm, and even more preferably 8 to 20 cm. Furthermore, a ring thickness (reference numeral 11 in FIG. 1) of 0.1 mm to 5.0 mm is preferable, as this enhances the effect of suppressing displacement of the rotating electrical machine protection ring and further improves the individual power density of the rotating electrical machine. The upper limit of the thickness is more preferably 3 mm or less, and even more preferably 1.5 mm or less.

[0036] (Method for Manufacturing a Rotating Electrical Machine Protection Ring) In the present invention, the rotating electrical machine protection ring is composed of a cylindrical laminate 1 made of a material containing a resin composition and reinforcing fibers. In the manufacturing apparatus, as illustrated in FIG. 2 , a predetermined path is formed from a bobbin 4 around which the material containing the resin composition and the reinforcing fiber bundle is wound to the start point of winding on the core 3 by a path-forming device (path-forming device) that mainly includes rolls and guides. In the present invention, such a predetermined path is not necessarily limited to a single path, but may be variously configured by combining path-forming devices depending on the purpose. In the method for manufacturing the laminate 1, the material is unwound from the bobbin 4, travels along the path while contacting a roll, guide, or the like, and is then wound around the core 3 in an annular shape multiple times to form the laminate 1. The traveling speed of the material is preferably 1 to 5 cm per second. In the present invention, a tensile stress within the range described below is applied to the material along the path from a certain point (including the point where travel begins) on the path of the traveling material to the start point of winding to the start point of winding. The application of tensile stress to the material can be carried out using a stress application mechanism 7 shown in FIG. 2 and the like.

[0037] The configuration of the stress applying mechanism 7 is not particularly limited, but examples include applying torque to the bobbin 4 by a brake or the like, applying frictional resistance to the material in the multi-stage rolls 5, and applying frictional resistance to the material in the nip rolls 6. Figures 2 and 3 show an example in which a stress applying mechanism 7 using the multi-stage rolls 5 is provided in the path from the bobbin 4 to the core 3, and the tension applied to the traveling material increases each time it passes through each roll of the multi-stage rolls.

[0038] The bobbin 4 is formed by winding the material around an inner tube. To separate the material from the bobbin without resistance, a film may be attached to the inner periphery of the material. The inner tube of the bobbin may also be made of metal.

[0039] As described above, the path forming devices are mainly rolls and guides, and include those that come into contact with the material to determine its travel path. Rolls include both free rolls and drive rolls. However, the path forming devices are not limited to rolls and guides. The stress applying mechanism 7 described above can also be a path forming device. On the other hand, measuring instruments such as tension meters and speedometers are not included in the above forming devices unless it is clear that they determine the material's travel path, since they do not usually determine the material's travel path, even if they come into contact with the material on the travel path.

[0040] The tensile stress (MPa) in the present invention can be calculated by dividing the tension applied to a material containing a resin composition and reinforcing fiber bundles by the cross-sectional area of ​​the material. For example, in the case of a tape-shaped material, the tension (N) applied to the tape-shaped material is determined by dividing the product of the thickness A (mm) and width B (mm) of the tape-shaped material. The thicknesses A (mm) and B (mm) of the tape-shaped material are obtained by sampling a 1-m length, measuring the thickness (mm) and width (mm) at 10 locations every 10 cm in the longitudinal direction using a micrometer or ruler, and rounding the average values ​​to two decimal places.

[0041] In the present invention, in order to prevent deformation of the core 3 during rotation, a tensile stress P within a predetermined range is applied to the material from a certain point on the predetermined path (the path from the bobbin to the start point of winding the material on the core 3). The "certain point" here may include the point at which the material starts to run (in the above configuration, the point at which the material is unwound from the bobbin 4 and starts to run). Note that if the stress applied to the material falls within the above-mentioned predetermined range of tensile stress, then falls outside the predetermined range of tensile stress and then falls within the predetermined range again, or if this occurs repeatedly, two or more points at which the tensile stress falls within the predetermined range are the "certain point."

[0042] The tensile stress P in the predetermined range is expressed in several patterns, including preferred embodiments, but the common technical idea in the present invention is to apply a predetermined tensile stress P to the material to cause it to run through the path, while suppressing breakage of the threads contained in the material and seepage of the resin composition.

[0043] In order to suppress yarn breakage, the main tension range pattern of the tensile stress P is either (1) a tensile stress of 300 MPa or more and 4000 MPa or less, (2) a tensile stress of 300 MPa or more and 3300 MPa or less, or (3) a tensile stress of 300 MPa or more and 2700 MPa or less.

[0044] Regarding the tensile stress P in the range of 300 MPa to 4000 MPa (hereinafter, the tensile stress in this range will be referred to as tensile stress 300-4000, and hereinafter, similarly expressed using the lower limit value-upper limit value of the stress), the tension applied to the material when it travels along the path may be an ultra-high tension of 4000 MPa. In the path where such a tensile stress of 300-4000 is applied to the material, in the present invention, the relationship between the temperature T of the traveling material and the Tg of the resin composition contained in the material is specified as described below. The range of the tensile stress P is preferably 300 MPa to 3700 MPa (tensile stress 300-3700). The preferred complex viscosity of the resin composition is as described below.

[0045] In the above (2) which expresses a preferred embodiment, the range of the predetermined tensile stress P is 300 MPa or more and 3300 MPa or less (tensile stress range 300-3300). The range of the tensile stress P is more preferably 300 MPa or more and 3000 MPa or less (tensile stress 300-3000). Furthermore, it is also conceivable to set the range to 300 MPa or more and 2700 MPa or less (tensile stress 300-2700) as in the above (3).

[0046] The lower limit of the tensile stress P is 300 MPa or more. However, if a resin composition that is relatively resistant to seepage, as described below, is used, the tensile stress may be relatively high. Therefore, from the viewpoint of suppressing displacement that occurs during rotor operation, 350 MPa or more is preferable, 400 MPa or more is more preferable, 450 MPa or more is even more preferable, and 500 MPa is most preferable.

[0047] When the lower limit is 400 MPa, the upper limit may be set to 4000 MPa, 3700 MPa, 3300 MPa, 3000 MPa, or 2700 MPa, and these may be described as tensile stress 400-4000, tensile stress 400-3700, tensile stress 400-3300, tensile stress 400-3000, or tensile stress 400-2700, respectively. The same applies when the lower limit is 350 MPa, 450 MPa, or 500 MPa.

[0048] In order to apply such tensile stress, in the manufacturing method according to the present invention, it is preferable to apply a desired stress from among the above-mentioned tensile stresses to the material traveling along the path. For example, as shown in Figures 2 and 3, a method of gradually applying tensile stress to the traveling material using a multi-stage roll 5 and a nip roll 6 is available. Another method of applying tensile stress is to apply torque to the bobbin 4 using a brake or the like.

[0049] The inventors have discovered that even when the same resin composition is used, lowering the temperature of the material traveling along the above-mentioned path can suppress the motion of molecules contained in the components of the resin composition, thereby improving the complex viscosity, suppressing thread breakage, and further suppressing exudation of the resin composition. On the other hand, even when the temperature of the material traveling along the above-mentioned path is the same, thread breakage and exudation of the resin composition can be suppressed if the glass transition temperature of the resin composition contained in the material is above a certain level. From this perspective, in the present invention, when the above-mentioned tensile stress is applied, the temperature of the material along the path within the range in which the tensile stress is applied is defined as T, and the glass transition temperature of the resin composition is defined as Tg. The difference ΔT between T and Tg, expressed by the following formula (I), satisfies ΔT < 30°C. Preferably, ΔT < 25°C, and more preferably, ΔT < 15°C. (I) ΔT = T - Tg The temperature T of the material traveling along the above-mentioned path can be determined by measuring the temperature of the material traveling along the above-mentioned path with a contact or non-contact thermometer. Here, when the temperature of the material varies depending on the position along the path, the temperature at the position showing the highest temperature is referred to. Such a temperature is preferably 0°C or higher and 50°C or lower, and more preferably 10°C or higher and 40°C or lower.

[0050] Furthermore, from the above viewpoint, in the present invention, as shown in FIG. 3, it is preferable to cool the material from a higher temperature to 20°C or less using a cooling mechanism 9 in the stress application process. For example, when a resin composition with a Tg of 5°C is used, the temperature of the material in the above-mentioned path is preferably less than 35°C. When a resin composition with a Tg of -20°C is used, it is preferable to reduce the temperature T of the material in the above-mentioned path to less than 10°C using the cooling mechanism 9, as shown in FIG. 3. If ΔT is 30°C or higher, breakage of the material, fiber breakage, and exudation of the resin composition may occur. The lower limit of the Tg is preferably -30°C, more preferably -15°C. The upper limit of the Tg is not particularly limited, but the Tg of resin compositions generally used for prepregs, etc., is up to 60°C. Since the temperature of the material in the above-mentioned path is preferably 0°C or higher, ΔT in this case is -60°C. That is, it is preferable that -60°C < ΔT < 30°C. Here, the Tg of the resin composition can be evaluated by differential scanning calorimetry (DSC) by raising the temperature from −50° C. to 300° C. at a rate of 5 to 10° C. / min. When measuring with DSC, a tape-shaped material may be used as the sample as long as it can be confirmed that the reinforcing fibers do not affect the measurement and do not reduce its accuracy.

[0051] The range in which ΔT is less than 30° C. may be partial in the path in which the tensile stress P is applied, but it is preferable that ΔT<30° C. be true over the entire path. When ΔT<30° C. be true over the entire path in which the tensile stress P is applied, yarn breakage during running becomes less likely to occur.

[0052] The cooling mechanism 9 may be a spot cooler or the like that directly cools the material, or a chiller that cools the path configuration device and then cools the material through the path configuration device. It is preferable to cool at least a portion of the material to 20°C or less by using such a cooling mechanism or the like before and / or during the stress application step.

[0053] In the present invention, in order to prevent the breakage of the material or partial thread breakage, the complex viscosity of the resin composition is set to 10 ４ It is preferably 10 Pa·s or more, and more preferably 10 ５ The complex viscosity of the resin composition is 10 Pa·s or more. ８ It is preferably 10 Pa·s or less, and more preferably 10 ７ When the material is run under high tension, the complex viscosity is 10 Pa·s or less. ４ If the viscosity is less than Pa·s, there is a greater tendency for thread breakage and exudation of the resin composition during the manufacturing process of the laminate 1 to increase. The complex viscosity of the resin composition contained in the material can be measured using a viscoelasticity measuring device (an apparatus in which the measurement object is sandwiched between upper and lower measuring jigs, such as the ARES manufactured by TA Instruments) for the resin composition before it is impregnated into the fiber bundle. Using flat parallel plates with a diameter of 40 mm for the upper and lower measuring jigs, the resin composition contained in the material is set between the upper and lower jigs so that the distance between the upper and lower jigs is 1 mm, and then measured in torsion mode under conditions of a heating rate of 1 to 5°C / min and a frequency of 0.5 Hz. Here, the complex viscosity refers to the complex viscosity at a temperature T along a path in the range in which the tensile stress according to the present invention is applied to the material in the complex viscosity versus temperature curve obtained by measurement.

[0054] Next, the material containing the resin composition and reinforcing fibers travels along a predetermined path and is then guided to a core 3 to be wound into a circular shape multiple times to form a cylindrical laminate. The core 3 is a component that will ultimately be fastened with the material, such as a rotor for a rotating electrical machine.

[0055] The laminate 1 may be formed by repeatedly winding the material containing the resin composition and reinforcing fibers in a 0° direction, with the circumferential direction of the core 3 shown in Figures 2 and 3 set as the reference (0°), i.e., by overlapping the winding at the same height position when the bottom surface of the core 3 is placed downward, or by spirally winding the material at a different angle from the reference direction. In this case, in the embodiment shown in Figures 2 and 3, the winding can be performed by rotating the core 3 in the direction of arrow 8.

[0056] Thereafter, the laminate 1 is subjected to heat and pressure by a method such as autoclave molding or wrap tape molding to harden the resin composition, thereby obtaining a rotating electrical machine protection ring.

[0057] (Rotating Electric Machine) The rotating electric machine according to the present invention includes a rotor and a rotating electric machine protective ring. As described above, the rotating electric machine protective ring is formed by winding a material containing a resin composition and a reinforced fiber bundle around the rotor in an annular shape multiple times and molding it into a cylindrical laminate, and as a result, the rotating electric machine protective ring is attached to the rotor. The manufacturing method described above is preferably used to manufacture such a rotating electric machine protective ring. In such a rotating electric machine, when the rotating electric machine protective ring attached to the rotor has an outer diameter of 6 cm or more and 23 cm or less, the rate of change of the outer diameter when the rotating electric machine is rotated at a rotation speed of 10,000 rpm can be 0.1% or less, and the rate of change of the outer diameter is preferably 0.09% or less, more preferably 0.08% or less, and particularly preferably 0.07% or less.

[0058] This technology suppresses deformation of the permanent magnet toward the outer diameter during high-speed rotation, enabling even higher rotation speeds, thereby improving the output or power density of such a rotating electric machine. The unit power density, which is the density of the power that can be generated by such a rotating electric machine alone, is preferably 8 kW / kg or more, more preferably 10 kW / kg or more, and is preferably 30 kW / kg or less.

[0059] (Electric Mobility Device) Furthermore, the present invention can provide an electric mobility device equipped with such a rotating electric machine. The electric mobility device referred to here includes, but is not limited to, electric vehicles, electric aircraft, and electric ships, as long as it is a mobility device driven by a rotating electric machine. Rotating electric machines for electric mobility require a larger outer diameter and higher rotation speed than those used for home appliances in order to increase output. The electric mobility device of the present invention has an improved output density of the rotating electric machine, enabling it to be lighter and more compact, thereby enabling improved cruising range and greater design freedom as an electric mobility device. (Method for Calculating Displacement During Rotation of a Rotating Electric Machine) The rate of change in the outer diameter of the rotating electric machine protection ring can be determined by a rotation test of the rotating electric machine. In the rotation test of the rotating electric machine, the rotating electric machine is rotated from a stationary state, and the rotation speed is gradually increased to 10,000 rpm, and then maintained for 20 seconds or more. Here, the rate of change of the outer diameter of the rotating electric machine protection ring is defined as the value obtained by multiplying the displacement of the outer diameter (displacement during the rotation test) when the rotating electric machine reaches 10,000 rpm in a rotation test and is held there for 20 seconds relative to the outer diameter of the rotating electric machine protection ring before rotation (the ring outer diameter before rotation) by 100. The outer diameter of the rotating electric machine protection ring before rotation can be measured using a diameter meter tape. The displacement of the outer diameter during the rotation test can be measured using a laser displacement meter while rotating the rotating electric machine, 20 seconds after the rotation speed reaches 10,000 rpm, and can be determined by reading the average of each displacement in the circumferential direction. Note that the sensitivity of the laser displacement meter measurement can be increased by applying paint to the surface of the rotating electric machine protection ring. The measurement points for the outer diameter of the ring before rotation and the amount of displacement during the rotation test are both at any position around the circumference of the rotating electric machine protection ring, at the center points in the direction of the rotation axis of each equally divided line segment when the ring is divided into six equal parts along the direction of the rotation axis from one end to the other in the width direction of the ring. The average of the outer diameters measured at these six center points before rotation is the outer diameter of the ring before rotation, and the average of the amounts of displacement measured at these six center points during the rotation test is the amount of displacement during the rotation test. The rotation means is not particularly limited, but it is sufficient if it can rotate the rotating electric machine stably up to a predetermined rotation speed, and a spin tester can be used.

[0060] The power density of a rotating electric machine is calculated by dividing the output of the rotating electric machine by the weight of the rotating electric machine. The output of a rotating electric machine is expressed as the product of the rotation speed and torque. The rotation speed and torque are measured using a general method such as using a motor bench.

[0061] A specific manufacturing example of a molding method for the rotating electrical machine protection ring of the present invention and a comparative example will be described below.

[0062] Example 1 In this example, an epoxy resin composition comprising the following components was used as the resin composition. Component [A]: Of the epoxy resins, 9.2 parts by mass of jER (registered trademark) 828, 10 parts by mass of jER (registered trademark) 1001, 25 parts by mass of jER (registered trademark) 1007, and 40.8 parts by mass of Epiclon (registered trademark) 830 were used as the [A1] bisphenol type, and 15 parts by mass of Epiclon (registered trademark) HP7200H was used as the [A2] dicyclopentadiene type. Component [B]: 4.5 parts by mass of DICY7 and 3 parts by mass of DCMU99 were used as curing agents that react with component [A]. Component [C]: 2 parts by mass of Vinylec (registered trademark) K was used as the thermoplastic resin.

[0063] The complex viscosity of this epoxy resin composition was measured using a viscoelasticity measuring device (ARES, TA Instruments). Flat parallel plates with a diameter of 40 mm were used as upper and lower measuring jigs, and the epoxy resin composition was set between the upper and lower jigs so that the distance between the upper and lower jigs was 1 mm. Measurement was then carried out in a torsion mode under conditions of a heating rate of 1.7°C / min and a frequency of 0.5 Hz. As a result, the complex viscosity at 25°C was 2 x 10 ５ It was Pa·s.

[0064] Next, this epoxy resin composition was impregnated into a sheet-like material obtained by spreading a plurality of carbon fiber bundles ("Torayca (registered trademark)" T800S-12K) to form a sheet having a fiber basis weight of 125 g / m ２This was made into a prepreg with a resin content of 24% by mass, which was then slit to obtain a 7 mm wide slit tape (tape-shaped material). The Tg of the epoxy resin composition of this slit tape was measured by differential scanning calorimetry (DSC), where the temperature was raised from -50°C to 300°C at a rate of 5°C / min, and the result was 3°C. The T800S-12K used in this example had a strand strength of 5,880 MPa.

[0065] Here, the strand strength was determined according to the following procedure in accordance with the resin-impregnated strand test method of JIS-R-7608 (2004). The formulation of the resin to be impregnated was "Celloxide (registered trademark)" 2021P (manufactured by Daicel Chemical Industries, Ltd.) / boron trifluoride monoethylamine (manufactured by Tokyo Kasei Kogyo Co., Ltd.) / acetone = 100 / 3 / 4 (parts by mass), and the curing conditions were atmospheric pressure, a temperature of 125°C, and a time of 30 minutes. The strength of 10 strands of carbon fiber bundles impregnated with resin was measured, and the average value was taken as the strand strength.

[0066] To simulate the yarn path when the tape-shaped material runs through a path construction device, an Instron universal testing machine (manufactured by Instron) was used in an environment of 25°C, and each end of the longitudinal direction of the tape-shaped material was firmly gripped with a chuck (the gripped portion is referred to as the "gripped portion"), with a crosshead speed of 2.5 mm / min, a distance between the gripped portions of 100 mm, and the number of samples N = 3. After measuring the temperature of the tape-shaped material with a contact thermometer to confirm that it was 25°C, a tensile stress was applied to the tape-shaped material, gradually increasing from 0 MPa up to 2500 MPa. The tensile stress in this example was calculated according to the above (method of calculating tensile stress).

[0067] When a tensile stress of 2500 MPa was applied, the tape-shaped material was evaluated for the presence or absence of partial thread breakage, and it was found that no partial thread breakage occurred.

[0068] The tape material described in this example was wrapped halfway around a roller made of SUS304 and having an outer diameter of 82 mm, and the temperature of the tape material was confirmed to be 25°C. With a 200 g weight attached to one end of the wrapped tape material and a tensiometer attached to the other end, a tensile stress was manually applied, gradually increasing from 0 MPa to 420 MPa. At this time, it was visually confirmed that the resin composition had not oozed from the tape material onto the surface of the roller.

[0069] It was shown that because the tape-shaped material can be wound around the outer circumference of the rotor in a rotating electric machine with high tensile stress, it is possible to manufacture a protective ring for a rotating electric machine that can suppress displacement that occurs during rotation.

[0070] (Example 2) The complex viscosity of the epoxy resin composition described in Example 1 was measured using the same measuring device and method as in Example 1. As a result, the complex viscosity at 14°C was 8 x 10 6 It was Pa·s.

[0071] Using the same testing machine as in Example 1, the tape-shaped material described in Example 1 was cooled to 14°C using the cooling mechanism, and a tensile stress was applied to the tape-shaped material, gradually increasing from 0 MPa to 2900 MPa. The tape-shaped material was evaluated for the presence or absence of partial thread breakage, and no partial thread breakage occurred.

[0072] Furthermore, the tape-shaped material described in Example 1 was used, and the presence or absence of seepage of the resin composition from the tape-shaped material was confirmed using the same method and conditions as in Example 1, except that the tape-shaped material was cooled to 14°C using a cooling mechanism. It was visually confirmed that the resin composition had not seeped out from the tape-shaped material onto the roller surface.

[0073] (Example 3) In this example, an epoxy resin composition comprising the following components was used as the resin composition. Component [A]: 100 parts by mass of "jER (registered trademark)" 828 was used as the epoxy resin. Component [B]: 4.5 parts by mass of DICY7 as a curing agent that reacts with component [A], and 2 parts by mass of DCMU99 as a curing accelerator were used.

[0074] The complex viscosity of this epoxy resin composition was measured using the same measuring device and method as in Example 1. As a result, the complex viscosity at 0°C was 4 x 10 ４ It was Pa·s.

[0075] Next, this epoxy resin composition was impregnated into one bundle (unspread) of the same carbon fiber bundle ("TORAYCA (registered trademark)" T800S-12K) as in Example 1 to obtain a towpreg with a resin content of 30 mass%. The Tg of the epoxy resin composition of this towpreg was measured using the same measuring device and method as in Example 1, and was found to be -25°C.

[0076] Using the same testing machine as in Example 1, the tape-shaped material was cooled to 0°C using the cooling mechanism, and the tensile stress was gradually increased from 0 MPa to 2400 MPa. The tape-shaped material was evaluated for the presence or absence of partial thread breakage, and no partial thread breakage occurred.

[0077] In addition, the tape-shaped material described in Example 3 was used to check for exudation of the resin composition from the tape-shaped material under the same method and conditions as in Example 1, except that the tape-shaped material was cooled to 0°C using a cooling mechanism.It was visually confirmed that the resin composition had not exuded from the tape-shaped material onto the roller surface.

[0078] Example 4 Using the rotating electrical machine protection ring manufacturing apparatus shown in Figure 2, the same tape-shaped material as in Example 1 was wound to form a laminate. In Figure 2, a cylindrical rotor was placed on the core, and the tape-shaped material was unwound from a bobbin, passed through a path configuration device, and wound around the outer periphery of the rotor. The path configuration device included a multi-stage roll 5 and a nip roll 6. The unwinding speed of the tape-shaped material was set to 3 m / min, and a tensile stress of 2000 MPa was applied to the tape-shaped material using the multi-stage roll 5 and the nip roll 6.

[0079] In this case, no partial thread breakage occurred in the tape-shaped material, and a good laminate was obtained in which the tape-shaped material was wound around the core with high tensile stress.

[0080] In this example, a rotor with a diameter of 150 mm and a width of 15 cm was used to mount the rotating electrical machine protection ring. The rotor had a ring-shaped structure in which a circle forming a circumferential direction about the rotation axis was divided into eight parts, with eight arc-shaped magnets attached to each shaft. The tape-shaped material constituting the laminate was the same as that used in Example 1.

[0081] The tape-shaped material was wound onto the rotor under a tension of 400 N (tensile stress of 571 MPa) until the thickness reached 1 mm, forming a laminate. The laminate thus attached to the rotor was pressed and heat-cured using an autoclave, often with a bagging film, to form a rotating electric machine protection ring, and a rotating electric machine was fabricated. The outer diameter of the rotating electric machine protection ring was 152 mm, as the slit tape was wound 1 mm thick around a rotor with a diameter of 150 mm.

[0082] A rotation test was conducted on the rotating electric machine fabricated by the above method, rotating it around the rotation axis at a rotation speed of 10,000 rpm. The outer diameter of the ring before rotation and the amount of displacement during the rotation test were measured. The rotation test was conducted according to the following procedure. The outer diameter of the rotating electric machine protective ring before rotation was measured using a diameter meter tape (manufactured by Nippon Doki Co., Ltd.) and confirmed to be 152 mm as described above. An air turbine spin tester was used as the rotation means to rotate the fabricated rotating electric machine from a stationary state, gradually increasing the rotation speed and maintaining it for at least 20 seconds after reaching 10,000 rpm. The amount of displacement of the outer diameter during the rotation test was measured using a laser displacement meter (manufactured by KEYENCE Corporation) while the rotating electric machine was rotating, 20 seconds after the rotation speed reached 10,000 rpm. The average of the displacement amounts at each measurement point in the circumferential direction was read and used as the displacement amount. The positions of each measurement point were as described in the section (Method for calculating displacement during rotation of a rotating electric machine). As a result, the rate of change in the outer diameter of the rotating electrical machine protection ring was 0.1% or less, confirming the effect of suppressing displacement.

[0083] Example 6 The rotor described in Example 5 was used, and the same material as in Example 1 was used as the tape-shaped material constituting the laminate.

[0084] The above-mentioned tape-shaped material slit tape was wound onto the rotor under a tension of 1500 N (tensile stress of 2143 MPa) until the thickness reached 1 mm to form a laminate, and a rotating electric motor protective ring was molded in the same manner as in Example 5, to produce a rotating electric motor.

[0085] A rotation test was conducted using the rotating electric machine manufactured using the above method in the same manner as in Example 5.The change rate of the outer diameter of the rotating electric machine protection ring was 0.1% or less, confirming the effect of suppressing displacement.

[0086] Comparative Example 1 The complex viscosity of the epoxy resin composition described in Example 3 was measured using the same measuring device and method as in Example 1, and the complex viscosity at 25° C. was 40 Pa·s.

[0087] Using the same testing machine as in Example 1, without using a cooling mechanism, the temperature of the tape-shaped material was confirmed to be 25°C, and the tape-shaped material described in Example 3 was subjected to a tensile stress gradually increased from 0 MPa up to 2200 MPa under the same conditions as in Example 1. The tape-shaped material was evaluated for the presence or absence of partial thread breakage. As a result, partial thread breakage occurred when a tensile stress of 2200 MPa was applied.

[0088] Furthermore, using the tape-shaped material described in Example 3, the presence or absence of exudation of the resin composition from the tape-shaped material was confirmed in the same manner and under the same conditions as in Example 1, except that no cooling mechanism was used and the temperature of the tape-shaped material was confirmed to be 25°C. As a result, it was visually confirmed that the resin composition had exuded from the tape-shaped material onto the roller surface.

[0089] Since partial thread breakage occurred at a tensile stress lower than in any of the examples, it is expected that there will be concerns about running along a route at high tension. Furthermore, even in the range of tensile stress lower than 2200 MPa, where thread breakage does not occur, there are conditions under which the resin composition may seep out when the thread is unwound from the bobbin or enters the stress-applying mechanism.

[0090] (Comparative Example 2) The tape-shaped material described in Example 1 was heated using a heating mechanism, and the tensile stress was gradually increased from 0 MPa to 2200 MPa using the same tester and conditions as in Example 1, except that the material temperature at that time was confirmed to be 60°C. Note that partial thread breakage occurred in the tape-shaped material when a tensile stress of 2200 MPa was applied. The complex viscosity at 60°C was 2 x 10 ２ It was Pa·s.

[0091] Furthermore, the tape-shaped material described in Example 1 was heated using a heating mechanism, and the presence or absence of exudation of the resin composition from the tape-shaped material was confirmed using the same method and conditions as in Example 1, except that the material temperature at that time was confirmed to be 60°C. As a result, it was visually confirmed that the resin composition had exuded from the tape-shaped material onto the roller surface.

[0092] Comparative Example 3 In this comparative example, the rotor described in Example 5 was used, and the same material as in Example 1 was used as the tape-shaped material constituting the laminate.

[0093] The above tape-shaped material was wound onto the rotor under a tension of 20 N (tensile stress of 29 MPa) until the thickness reached 1 mm to form a laminate, and a rotating electric motor protection ring was molded in the same manner as in Example 5, to produce a rotating electric motor.

[0094] When a rotation test was conducted on the rotating electrical machine manufactured by the above method in the same manner as in Example 5, the rate of change in the outer diameter of the rotating electrical machine protection ring was 0.3%, which was greater than 0.1%, and no displacement suppression effect was confirmed. This is thought to be due to insufficient tensile stress during winding.

[0095]

[0096] The rotating electric machine protection ring obtained by the present invention is attached to the outside of the rotor of a rotating electric machine such as a generator or an electric motor, and can be used to protect the rotor, which includes a magnet, from damage caused by centrifugal force when the rotating electric machine is operating. The present invention can also provide a rotating electric machine composed of such a rotating electric machine protection ring and rotor. It can also be used to protect flywheels used for energy storage from damage caused by centrifugal force. Furthermore, the present invention can also provide an electric mobility device equipped with such a rotating electric machine.

[0097] The rotating electric machine protection ring obtained by the present invention can be preferably applied to, for example, the above-mentioned SPM type electric motor, and since the falling off of the permanent magnet from the rotor due to centrifugal force during operation is suppressed, the rotating electric machine can be rotated at high speed. It can also be preferably applied to the above-mentioned IPM type electric motor, a winding type using electromagnets, a reluctance type using magnetic resistance, an induction type electric motor without magnets, etc. With such a rotating electric machine protection ring, damage to the electromagnetic steel plate and the like due to centrifugal force during operation is suppressed, and the rotating electric machine can be rotated at high speed.

[0098] REFERENCE SIGNS LIST 1 Laminate 2 Material winding direction 3 Core 4 Bobbin 5 Multi-stage roll 6 Nip roll 7 Stress applying mechanism 8 Arrow indicating core rotation direction 9 Cooling mechanism 10 Outer diameter of rotating electrical machine protection ring 11 Thickness of rotating electrical machine protection ring

Claims

1. A method for manufacturing a protection ring for a rotating electric machine, comprising applying a tensile stress to a material containing a resin composition and reinforced fiber bundles, running the material along a predetermined path, and then winding the material into a ring shape several times to form a cylindrical laminate, wherein a tensile stress P of 300 MPa or more and 4000 MPa or less is applied to the material from a certain point along the path, and the path along which the tensile stress P is applied has a region in which the difference ΔT between T and Tg, expressed by the following formula (I), satisfies ΔT<30°C, where T is the temperature of the material while the tensile stress P is applied, and Tg is the glass transition temperature of the resin composition contained in the material. (I) ΔT=T-Tg 2. A method for manufacturing a protection ring for a rotating electrical machine as set forth in claim 1, wherein the tensile stress P is in the range of 300 MPa or more and 3300 MPa or less.

3. A method for manufacturing a rotating electrical machine protection ring as set forth in claim 1, wherein the tensile stress P is in the range of 300 MPa or more and 2700 MPa or less.

4. A method for manufacturing a protection ring for a rotating electrical machine according to any one of claims 1 to 3, wherein ΔT<30° C. is satisfied over the entire path along which the tensile stress P is applied.

5. While the tensile stress P is applied, the complex viscosity of the resin composition contained in the material is 10 ４ Pa・s or more 10 ８ The method for manufacturing a protection ring for a rotating electrical machine according to any one of claims 1 to 4, wherein the hardness is Pa·s or less.

6. A method for manufacturing a protection ring for a rotating electrical machine according to any one of claims 1 to 5, further comprising a stress applying step for increasing the tensile stress P to a desired value.

7. A method for manufacturing a protection ring for a rotating electrical machine according to claim 6, wherein at least a portion of the material is cooled to 20° C. or less before and / or during the stress application step.

8. A rotating electric machine having a rotor and a rotating electric machine protective ring, wherein the rotating electric machine protective ring is formed by winding a material containing a resin composition and a reinforced fiber bundle in a ring shape around the rotor multiple times and molding it into a cylindrical laminate having an outer diameter of 6 cm or more and 23 cm or less, and wherein the rate of change of the outer diameter when operated at a rotation speed of 10,000 rpm is 0.1% or less.

9. The rotating electric machine according to claim 8, having a unit power density of 8 kW / kg or more.

10. An electric mobility device equipped with the rotating electric machine according to claim 9.