Annular laminated core material and manufacturing method thereof

Abstract

To provide an annular laminated core material that eliminates iron loss due to eddy currents generated from a joint of each core material and does not require an additional step and a manufacturing method of the same.SOLUTION: An annular laminated core material 1 includes a core body 6 in which a plurality of annular core materials is formed by laminating into a cylindrical shape and a groove extending in an axial direction on an inner peripheral surface on an inner side in a radial direction or on an outer peripheral surface on an outer side in the radial direction is formed, a resin molded body 2 formed by integrally molding a pair of bodies 2a formed to cover at least a part of both axial end surfaces of the core body 7 and a connecting portion 2b connecting the pair of bodies 2a, and an insulating sheet 6 disposed on an inner surface of the groove. Both ends of the insulating sheet 6 in the axial direction are in contact with the bodies 2a of the resin molded body 2, respectively.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an annular laminated core material and a method for producing an annular laminated core material. [Background technology]

[0002] Conventionally, there has been known annular laminated core materials, such as motor cores, which are formed by joining a predetermined number of annular core materials punched from a strip-shaped thin plate material in a stacked state. For example, an automatic lamination method is known as a method for manufacturing annular laminated core materials. In the automatic lamination method, first, while the strip-shaped thin plate material is intermittently transferred by a progressive die device, a desired punching process is sequentially performed on the thin plate parts for the core material of the strip-shaped thin plate material. Next, the thin plate parts for the core material are punched out by an outer diameter punch, separated from the strip-shaped thin plate material, and punched out sequentially into the die. Then, the punched-out core materials are joined in a stacked state in a predetermined number of sheets by a crimping joining means, which is a type of temporary fixing means previously provided on the core material.

[0003] Common crimping means for use in the in-mold automatic stacking method include, for example, providing each core material with a cut-and-raised portion in advance, as in Patent Document 1 (JP Patent Publication No. 58-116033), or providing a embossed protrusion (dowel) as in Patent Document 2 (JP Patent Publication No. 49-37103), and crimping each of adjacent core materials above and below in the stacked state using the cut-and-raised portion or the embossed protrusion.

[0004] Laminated core materials are also known in which the individual core materials are bonded together, for example, by adhesive or by a laser beam. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 58-116033 [Patent Document 2] Japanese Patent Publication No. 49-37103 Summary of the Invention [Problem to be solved by the invention]

[0006] However, with the above-mentioned crimping connection method, the connection parts using cut-and-raised portions and stamped-out protrusions remain intact even when the motor is assembled, which causes problems such as eddy currents to occur in the crimped connection parts, resulting in a reduction in efficiency of several percent due to iron loss.

[0007] In addition, in the method of bonding using a direct-adhesive material or a laser beam, after the adhesive application or laser beam irradiation process, an additional process of fitting a resin molded body into a laminated core material was required to ensure electrical insulation with the windings.

[0008] Therefore, an object of the present invention is to provide an annular laminated core material that eliminates iron loss due to eddy currents generated at the joints between each core material and does not require any additional processes, and a manufacturing method thereof. [Means for solving the problem]

[0009] The present invention is an annular laminated core material, characterized in that it comprises a core body formed by stacking a plurality of annular core materials into a cylindrical shape, the core body having an axially extending groove formed on its radially inward inner surface or its radially outward outer surface, a pair of body portions formed to cover at least a portion of both axial end surfaces of the core body, a resin molded body in which a connecting portion connecting the pair of body portions is integrally molded, and an insulating sheet arranged on the inner surface of the groove, and both axial end portions of the insulating sheet abut against the body portions of the resin molded body, respectively.

[0010] According to the present invention having the above configuration, the pair of main body parts of the resin molded body are integrated by the connecting part, and further, the insulating sheet and the resin molded body are connected by abutting each other, so that the laminated core material can be integrated without temporary fixing by crimping, adhesive, etc. This makes it possible to suppress iron loss without the need to provide a crimping joint for crimping the core material, and does not require additional processes such as applying an adhesive or using a laser beam.

[0011] In the present invention, the core body is preferably formed with a through hole extending between both end faces in the axial direction, and the connecting portion passes through the through hole of the core body to connect the pair of body portions. According to the present invention having the above-mentioned configuration, when the resin molded body is molded, the molten resin passes through the through hole and fills the space corresponding to the pair of main body portions and the connecting portion, thereby making it possible to integrate the main body portion and the connecting portion.

[0012] In the present invention, a groove is preferably formed on the inner or outer peripheral surface of the core body, extending between both axial end faces, and the connecting portion passes through the groove of the core body to connect the pair of body portions. According to the present invention having the above-mentioned configuration, when the resin molded body is molded, the molten resin passes through the circumferential groove portion and fills the space corresponding to the pair of main body portions and the connecting portion, thereby making it possible to integrate the main body portion and the connecting portion.

[0013] In the present invention, preferably, both axial surfaces of the annular core material are flat, and the flat surfaces of each core material are in direct contact with the flat surfaces of the adjacent core material. According to the present invention having the above configuration, iron loss can be further suppressed.

[0014] In the present invention, the insulating sheet and the resin molded body are preferably connected without using an adhesive. According to the present invention having the above configuration, an annular laminated core material can be manufactured without performing an additional step such as bonding.

[0015] In the present invention, the axial length of the contact portion between the insulating sheet and the resin molded body is preferably 0.5 mm or more. According to the present invention having the above configuration, if the axial length of the contact portion between the insulating sheet and the resin molded body is 0.5 mm or more, when linear segment conductors are arranged in the grooves of the annular laminated core material 1 and the core materials are bent, there will be no misalignment between them and the core materials will be able to withstand the load applied when bent.

[0016] In the present invention, the insulating sheet and the resin molded body are preferably connected by impregnating the surface of the insulating sheet that comes into contact with the resin molded body with the resin that constitutes the resin molded body. According to the present invention having the above configuration, the insulating sheet and the resin molded body can be more firmly connected to each other.

[0017] In the present invention, the resin molded body is preferably formed using a polymer having an amide bond, and the surface of the insulating sheet in contact with the resin molded body is preferably composed of a polymer having an amide bond. According to the present invention having the above configuration, the polymer and the insulating sheet are entangled at the molecular level, and the insulating sheet and the resin molded body can be more firmly connected to each other.

[0018] In the present invention, preferably, the resin molded body is formed using a polymer having an amide bond, and the surface of the insulating sheet that contacts the resin molded body is composed of aramid paper made of aramid fibrids and aramid short fibers. According to the present invention having the above configuration, the polymer and the insulating sheet are entangled at the molecular level, and the insulating sheet and the resin molded body can be more firmly connected to each other.

[0019] The motor of the present invention uses a stator in which a winding is wound around the above-mentioned annular laminated core material. According to the motor having the above configuration, the above-mentioned operational effects are achieved.

[0020] The motor generator of the present invention uses a stator in which a winding is wound around the above-mentioned annular laminated core material. According to the motor generator configured as above, the above-mentioned operational effects are achieved.

[0021] The generator of the present invention uses a stator having a winding wound around an annular laminated core material. According to the generator having the above configuration, the above-mentioned operational effects are achieved.

[0022] The present invention is a manufacturing method for annular laminated core material, which includes an arrangement step of arranging a core body formed by stacking a plurality of annular core blocks to form a cylindrical shape, and having an axially extending groove formed on its radially inner inner surface or its radially outer outer surface, in a molding die so that an insulating sheet is disposed in the groove, and a resin molding step of injecting resin into the molding die to integrally mold a resin molded body including a pair of body portions formed to cover at least a portion of both axial end surfaces of the core body, and a connecting portion connecting the pair of body portions.

[0023] According to the present invention configured as above, the main body portion and the connecting portion can be integrally formed, and the laminated core materials can be integrated without temporary fixing by caulking, adhesive or the like. Effect of the Invention

[0024] According to the present invention, it is possible to provide an annular laminated core material that eliminates iron loss due to eddy currents generated at the joints between core materials and does not require any additional processes, and a manufacturing method thereof. [Brief description of the drawings]

[0025] [Figure 1] FIG. 1 is a schematic perspective view showing a configuration of an annular laminated core material according to one embodiment of the present invention. [Diagram 2] 2 is a perspective view showing a core body of the annular laminated core material shown in FIG. 1. [Diagram 3] 3 is a perspective view showing a core material constituting the core body shown in FIG. 2. [Figure 4] 2 is a perspective view showing an insulating sheet of the annular laminated core material shown in FIG. 1. [Diagram 5] FIG. 11 is a perspective view showing a core body of an annular laminated core material according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An annular laminated core material and a method for producing the same according to one embodiment of the present invention will be described below with reference to the drawings, but the present invention is not particularly limited thereto.

[0027] (Annular laminated core material) FIG. 1 is a schematic perspective view showing the configuration of an annular laminated core material according to one embodiment of the present invention. As shown in FIG. 1, the annular laminated core material is cylindrical, has a plurality of arms extending radially inward on its inner peripheral surface, and has a shape in which grooves are formed between the arms. In the annular laminated core material 1, the axial length of the contact portion between the insulating sheet and the resin molded body is preferably 0.5 mm or more. The annular laminated core material according to this embodiment is used as a stator for a motor, a motor generator, or a generator, for example, by winding a winding around each arm.

[0028] (Core body) Fig. 2 is a perspective view showing the core body of the annular laminated core material shown in Fig. 1. As shown in Fig. 2, the core body 4 is a cylindrical member formed by laminating a plurality of annular core materials 8, and is formed so that a plurality of openings on the inner peripheral surface extend in the axial direction. Note that although the boundaries of the laminated core materials 8 that form the core body 4 are not necessarily visible, they are shown in Figs. 1, 2 and 5 for the purpose of explanation.

[0029] FIG. 3 is a perspective view showing a core material constituting the core body shown in FIG. 2. As shown in FIG. 3, the core material 8 is a plate-shaped member formed with flat surfaces on both axial sides, and has a cross section in which the radially outer peripheral side of the approximately H-shaped portion is connected in a circular shape. The core material 8 includes an annular ring portion 8a, a plurality of arms 8b extending circumferentially inward from the annular ring portion 8a, and protruding portions 8c extending circumferentially from the tip portions of the arms 8b. Between each of the arms 8b, a groove portion 8d having a substantially trapezoidal shape is formed, surrounded by the adjacent arms 8b, the annular portion 8a, and the protruding portions 8c. In addition, six outer peripheral groove portions 8e are formed at equal angular intervals in the circumferential direction on the outer peripheral surface of the annular portion 8a. As the material of the core material 8, a metal such as a silicon steel plate can be used.

[0030] As shown in FIG. 2, the core body 4 is formed by stacking a plurality of core materials 8 without any temporary fixing means. That is, the surface of each core material 8 does not have any cut-and-raised portion or embossed protrusion for crimping. In addition, the flat surfaces of the core materials 8 adjacent in the axial direction are directly in contact with each other, and there is no adhesive between the core materials 8, and there is no welding trace by the laser beam. The core body 4 has the same cross-sectional shape over the entire axial length, and includes a cylindrical portion 4a, a plurality of arm portions 4b extending circumferentially inward from the cylindrical portion 4a, and protruding portions 4c extending from the tips of the arm portions 4b on both sides in the circumferential direction. The axial thickness of the core body 4 is equal to the thickness of the annular laminated core material 1 excluding the pair of main body portions 2a of the resin molded body 2 from the axial direction. The cylindrical portion 4a of the core body 4 is formed by stacking annular portions 8a of the core material 8, the arm portions 4b of the core body 4 are formed by stacking arm portions 8b of the core material 8, and the protrusion portions 4c of the core body 4 are formed by stacking protrusion portions 8c of the core material 8.

[0031] Between each arm 4b, a substantially trapezoidal groove 4d is formed, which is surrounded by the adjacent arm 4b, the cylindrical portion 4a, and the protruding portion 4c and extends in the axial direction. The groove 4d of the core body 4 is formed by the grooves 8d of the laminated core materials 8 continuing in the axial direction. In addition, six outer peripheral grooves 4e are formed on the outer peripheral surface of the cylindrical portion 4a at equal angular intervals in the circumferential direction and extending in the axial direction. The outer peripheral groove 4e of the core body 4 is formed by laminating the outer peripheral grooves 8e of a plurality of core materials 8.

[0032] In this embodiment, the outer peripheral groove 4e is formed on the outer peripheral surface of the core body 4, and the connecting portion 2b is formed in the outer peripheral groove 4e. However, the present invention is not limited to this. For example, as shown in FIG. 5, a through hole 104b penetrating the core body 104 in the axial direction may be formed. In this case, the outer peripheral groove 4e is not necessary. When the core body 104 having such a configuration is used, a connecting portion is formed in the through hole 104b, and the main body portions 2a can be connected to each other through the through hole 104b. When such a through hole is formed, it is preferable to form it in the cylindrical portion 104a. Also, in this embodiment, the groove 4d is formed on the inner peripheral surface on the radial inner side of the core body 4, but a groove may be formed on the outer peripheral surface on the radial outer side of the core body 4. In this case, instead of the outer peripheral groove 4e, an inner peripheral groove extending in the axial direction may be formed on the inner peripheral surface on the radial inner side, and a connecting portion of the resin molded body may be formed in the inner peripheral groove, or a through hole may be formed in the cylindrical portion, and a connecting portion of the resin molded body may be formed in the through hole.

[0033] (insulation sheet) FIG. 4 is a perspective view showing an insulating sheet of the annular laminated core material shown in FIG. 1. As shown in FIG. 4, the insulating sheet 6 has a substantially U-shaped cross section in the axial direction and has the same axial length as the annular laminated core material 1. The insulating sheet 6 is formed by folding a long strip-shaped sheet material, and has a central portion 6a, a left bent portion 6b, and a right bent portion 6c. The central portion 6a has a width equal to the width of the bottom of the groove portion 4d of the core body 4. The left bent portion 6b and the right bent portion 6c have a width equal to the surface extending in the radial direction of the groove portion 4d of the core body 4. The radial inner end edges of the left bent portion 6b and the right bent portion 6c are bent toward each other to form tip bent portions 6d and 6e.

[0034] As shown in FIG. 1, the insulating sheet 6 is disposed on the inner surface of each groove 4d of the core body 4. The central portion 6a of the insulating sheet 6 is disposed on the bottom (the radially outer surface) of the groove 4d, and the left bent portion 6b and the right bent portion 6c are disposed on the surface extending in the radial direction of the groove 4d. The tip bent portions 6d and 6e are disposed on the radially outer surface of the protruding portion 8c. In addition, both axial ends of the insulating sheet 6 protrude outward from both axial end faces of the core body 4 by a length equal to the thickness of the main body portion 2a of the resin molded body 2. The insulating sheet 6 is provided to insulate between the winding of the motor and the inner peripheral surface of the groove 4d of the core body 4 when the winding is wound around the arm portion 4b of the core body 4.

[0035] In this embodiment, insulating paper, nonwoven fabric, film, or a composite or laminated sheet thereof can be used as the insulating sheet. For example, insulating paper such as aramid paper made of aramid fibrids and aramid short fibers, plastic films such as polyphenylene sulfide film, polyimide film, polyether ether ketone film, polyethylene terephthalate film, polyethylene naphthalate film, and laminated sheets thereof can be used. In particular, a laminated sheet containing aramid paper made of aramid fibrids and aramid short fibers on at least one side is preferred. Here, as the adhesive used to laminate the aramid paper, a suitable adhesive commonly used in the technical field can be used, and examples of such adhesives include, but are not limited to, adhesives such as epoxies, acrylics, phenols, polyurethanes, silicones, polyesters, and amides. In addition, when the above-mentioned film is laminated with an adhesive, the film is usually stretched in many cases, and when a motor bobbin is manufactured by the melt injection molding method of the present invention described later, deformation of the laminated sheet due to shrinkage is likely to occur. For this reason, a laminated sheet in which a film formed by melt-forming a polymer is superimposed on the above-mentioned aramid paper and heated and pressurized to melt-impregnate the polymer into the aramid paper, a laminated sheet in which a polymer paper product (web) and aramid paper are laminated or superimposed and heated and pressurized to melt-impregnate the resin into the aramid paper, a laminated sheet in which a resin is melt-extruded onto the aramid paper and heat-fused, or the like is preferably used.

[0036] The number of layers of the laminated sheet can be appropriately selected depending on the use and purpose of the laminate. For example, as described in JP-A-2006-321183, a two-layer laminated sheet of a polymer and an aramid paper, which is made of an aromatic polyamide resin prepared by a method of melt-extruding a resin onto an aramid paper and heat-fusing it, and an epoxy-containing phenoxy resin having an epoxy group in the molecule, and the ratio of the epoxy-containing phenoxy resin is 30 to 50 mass%, and a three-layer laminated sheet of an aramid paper, a polymer, and an aramid paper, can be mentioned, but is not limited thereto.

[0037] If the adhesiveness between the insulating sheet and the resin molded body described below is insufficient and peels off when winding the wire, it is preferable to improve the adhesiveness by surface-treating the surface of the insulating sheet that comes into contact with the resin molded body. Examples of surface treatments include plasma surface treatment, corona surface treatment, and surface treatment by immersion in liquid. By carrying out such surface treatments, the surface energy of the insulating paper surface is improved and the interfacial energy with the resin molded body is reduced, resulting in improved adhesiveness with the resin molded body. Plasma surface treatment is particularly preferable because of its ease of treatment.

[0038] The thickness of the insulating sheet can be appropriately selected depending on the application and purpose of the insulating sheet, and any thickness can be selected as long as there is no problem with processability such as folding, winding, etc. In general, from the viewpoint of processability, a thickness within a range of 50 μm to 1000 μm (particularly preferably 70 to 200 μm) is preferable, but is not limited thereto.

[0039] (Aramid) In this embodiment, aramid means a linear polymeric compound (aromatic polyamide) in which 60% or more of amide bonds are directly bonded to an aromatic ring. Examples of such aramid include polymetaphenylene isophthalamide and its copolymers, polyparaphenylene terephthalamide and its copolymers, and poly(paraphenylene)-copoly(3,4'-diphenyl ether) terephthalamide. These aramids are industrially produced by conventionally known interfacial polymerization methods, solution polymerization methods, etc. using isophthalic acid chloride and metaphenylenediamine, and are available as commercial products, but are not limited thereto. Among these aramids, polymetaphenylene isophthalamide is preferably used because it has good moldability, heat adhesion, flame retardancy, heat resistance, and other properties.

[0040] (Aramid Fibre) In the present embodiment, the aramid fibrids are film-like aramid particles having papermaking properties, and are also called aramid pulp (see JP-B-35-11851, JP-B-37-5732, etc.).

[0041] It is widely known that aramid fibrids are used as a papermaking raw material after being disintegrated and beaten in the same manner as ordinary wood pulp, and so-called beating can be performed in order to maintain the quality suitable for papermaking. This beating can be performed by a disc refiner, beater, or other papermaking raw material processing equipment that exerts a mechanical cutting action. In this operation, the morphological change of the fibrids can be monitored by the freeness test method (freeness) specified in the Japanese Industrial Standard P8121. In this embodiment, the freeness of the aramid fibrids after beating is 10 cm 3 ~300cm 3 (Canadian Freeness (JISP8121)). If the freeness of the fibrid is greater than this range, the strength of the aramid paper made from it may decrease. 3 If you try to obtain a freeness smaller than 10 cm, the efficiency of using the mechanical power you put in will decrease, and the amount of processing per unit time will often decrease. Furthermore, the fibrids will become too fine, which will tend to reduce the so-called binder function. 3 No significant advantage is observed when attempting to obtain a freeness less than 100%.

[0042] (Aramid short fiber) Aramid short fibers are cut fibers made of aramid. Examples of such fibers include those available under trade names such as "Teijinconex (registered trademark)" from Teijin Limited and "Nomex (registered trademark)" from DuPont, but are not limited to these.

[0043] The length of the aramid short fibers can generally be selected from the range of 1 mm or more and less than 50 mm, preferably 2 to 10 mm. If the length of the short fibers is less than 1 mm, the mechanical properties of the sheet material are reduced, while if the length is 50 mm or more, entanglement, bundling, etc. are likely to occur during the production of aramid paper by a wet method, which can easily cause defects.

[0044] (aramid paper) In the present embodiment, the aramid paper is a sheet-like material mainly composed of the above-mentioned aramid fibrids and aramid short fibers, and generally has a thickness within a range of 20 μm to 1000 μm, preferably 25 to 200 μm. Furthermore, the aramid paper generally has a thickness of 10 g / m 2 ~1000g / m 2 , preferably 15 to 200 g / m 2 Here, the mixing ratio of the aramid fibrids and the aramid short fibers can be any ratio, but the ratio (mass ratio) of the aramid fibrids / aramid short fibers is preferably 1 / 9 to 9 / 1, more preferably 2 / 8 to 8 / 2, and particularly preferably 3 / 7 to 7 / 3, but is not limited to this range.

[0045] Aramid paper is generally manufactured by a method of mixing the above-mentioned aramid fibrids and aramid short fibers and then forming them into a sheet.Specifically, for example, the method of forming a sheet by utilizing air flow after dry blending the above-mentioned aramid fibrids and aramid short fibers, the method of dispersing and mixing the aramid fibrids and aramid short fibers in a liquid medium, and then discharging them onto a liquid-permeable support, such as a net or belt, forming them into a sheet, removing the liquid, and drying them, etc. can be applied, but among these, the so-called wet papermaking method using water as a medium is preferably selected.

[0046] In the wet papermaking method, a single or mixture of aqueous slurries containing at least aramid fibrids and aramid short fibers are generally fed to a papermaking machine, dispersed, dehydrated, squeezed, and dried, and then wound into a sheet. Papermaking machines that can be used include Fourdrinier papermaking machines, cylinder papermaking machines, tilted papermaking machines, and combination papermaking machines that combine these. When using a combination papermaking machine, slurries with different blending ratios are formed into sheets and combined to obtain a composite sheet consisting of multiple paper layers. Additives such as dispersibility improvers, antifoamers, and paper strength enhancers are used as necessary during papermaking.

[0047] The aramid paper obtained as described above can be heat-pressed between a pair of rolls at high temperature and high pressure to improve its density and mechanical strength. When using metal rolls, the heat-pressing conditions can be, for example, in the range of a temperature of 100 to 400°C and a linear pressure of 50 to 400 kg / cm, but are not limited thereto. A plurality of aramid papers can be laminated during heat-pressing. The heat-pressing process can be carried out a plurality of times in any order.

[0048] (Resin molding) The resin molded body 2 includes a pair of main body parts 2a formed along both axial end faces of the core body 4, and six connecting parts 2b connecting the edges of the outer periphery of the pair of main body parts 2a. The main body parts 2a have a thickness equivalent to the distance between the axial end faces of the core body 4 and the end of the insulating sheet 6, and have the same cross-sectional shape as the core body 4 (core material 8). That is, the main body part 2a includes an annular ring part 2a1, a plurality of arm parts 2a2 extending circumferentially inward from the annular ring part 2a1, and protruding parts 2a3 extending circumferentially on both sides from the tip parts of the arm parts 2a2. Between each arm part 2a2, a groove part 2a4 having a substantially trapezoidal shape is formed, which is surrounded by the adjacent arm part 2a2, the annular part 2a1, and the protruding part 2a3. The bottom of the groove 2a4 is in contact with the radial outer peripheral surface of the central portion 6a of the insulating sheet 6, the left bent portion 6b and the right bent portion 6c of the insulating sheet 6 are in contact with the side surface of the arm portion 2a2, and the tip bent portions 6d and 6e of the insulating sheet 6 are in contact with the radial outer peripheral surface of the protruding portion 2a3. The main body portion 2a of the resin molded body 2 is provided to insulate between the winding and the upper surface of the arm portion 4b of the core body 4 when the winding of the motor is wound around the arm portion 4b of the core body 4. In this embodiment, the main body portion 2a is formed so as to cover the entire axial end surface of the core body 4, but it is sufficient that the main body portion 2a is in contact with at least the axial end portion of the insulating sheet 6 and covers the arm portion 4b of the core body 4 on which the winding of the motor is arranged. The resin constituting the resin molded body 2 is impregnated into the surface of the insulating sheet 6 that is in contact with the resin molded body 2, and the resin molded body 2 and the insulating sheet 6 are thereby connected to each other. In this embodiment, the outer circumferential surfaces of the portions of the insulating sheet 6 that protrude from the core body 4 at both ends are in contact with the resin molded body 2 .

[0049] The connecting portions 2b are formed in the outer circumferential groove 4e of the core body 4 and connect the pair of body portions 2a through the outer circumferential groove 4e. The connecting portions 2b are provided on the outer circumferential surface of the core body 4 at equal angular intervals.

[0050] In this embodiment, the material constituting the resin molded body 2 may be, for example, PPS resin (polyphenylene sulfide resin), acrylonitrile-butadiene-styrene copolymer resin, polyimide resin, polyethylene terephthalate resin, polyacetal resin, polymers containing amide bonds such as polyamide 6, polyamide 66, polyamide 612, polyamide 11, polyamide 12, copolymer polyamide, polyamide MXD6, polyamide 46, methoxymethylated polyamide, and semi-aromatic polyamide, or a polymer containing a polyamide resin composition as shown in JP-A-2006-321951, or a mixture thereof, or a mixture of the above polymer and an inorganic substance such as glass fiber. The resin molded body 2 is produced by a melt injection molding method in which the above material is injected (injected) in a molten state into a desired mold and then cooled and removed from the mold. In particular, a molded body of a mixture of semi-aromatic polyamide and glass fiber is preferable because it has high heat resistance and good adhesion to a laminated sheet including aramid paper. Examples of such mixtures include, but are not limited to, DuPont's Zytel® HTN51G, 52G, and the like.

[0051] It is preferable to form a groove for positioning the winding in the part of the resin molded body 2 that comes into contact with the winding, as this stabilizes the position of the winding, enabling highly accurate aligned winding, thereby improving the efficiency of motor generators, etc.

[0052] (Manufacturing method of annular laminated core material) The annular laminated core material 1 of this embodiment can be manufactured as follows. That is, first, a desired die-cutting process is performed on a strip-shaped thin plate material, and then the core material is separated by punching with an outer diameter punch. The punched core material 8 is then stacked in a cylindrical cavity of an injection molding die to form the core body 4. Note that the core material 8 does not have a cut-and-raised portion or a embossed protrusion for riveting, and the core material 8 is not bonded by an adhesive or a laser beam, and each core material 8 has no trace of a temporary fixing means. Next, an insulating sheet 6 is placed in the groove 4d of the core body 4. At this time, the insulating sheet 6 is placed so that both ends of the insulating sheet 6 protrude from both end faces of the core body 4 by a length equivalent to the thickness of the main body 2a of the resin molded body 2 (placement step). At this time, the insulating sheet 6 is placed so that the distance between both axial end faces of the core body 4 and the inner surface of the cavity is the same as the protruding length of the insulating sheet 6, and the core body 4 is placed so that the inner and outer circumferential surfaces are in contact with the inner surface of the cavity. As a result, a space corresponding to the main body portion 2a of the resin molded body 2 is formed between both end faces of the core body 4 and the inner surface of the cavity, and a space corresponding to the connecting portion 2b extending in the axial direction is formed between the outer peripheral groove portion 4e of the core body 4 and the inner peripheral surface of the cavity. Note that in this embodiment, the insulating sheet 6 is attached after the core body 4 is formed by stacking the core material 8 in the cavity, but this is not limiting, and the core body 4 with the insulating sheet 6 attached may be placed in the cavity.

[0053] Next, the resin that constitutes the resin molded body 2 is injected into the cavity, filling the space between the core body 4 and the inner surface of the cavity. Then, as the resin hardens, the resin molded body 2 is formed, in which the main body portion 2a and the connecting portion 2b are integrated (resin molding step). Through the above steps, the core material 8 that constitutes the laminated core body 4 is fixed by the resin molded body 2 and the insulating sheet 6, and an integrated annular laminated core material 1 can be manufactured.

[0054] In the manufacturing method of this embodiment, a plurality of core materials 8 are laminated in an injection molding cavity without any trace of a temporary fixing means between each core material 8, and an insulating sheet 6 is arranged in advance so that at least a part of the insulating sheet 6 is in contact with a part corresponding to the resin molded body 2, so that the molten polymer forming the resin molded body 2 can be impregnated into at least a surface part of the insulating sheet 6. By producing an annular laminated core material 1 in which a part of the resin molded body 2 and the insulating sheet 6 are connected and fixed in this manner, there is no need to use an adhesive, and they can be connected and fixed at the same time when the resin molded body is produced. Here, impregnation means that the molten polymer penetrates into the surface of the insulating sheet. In particular, when the insulating sheet contains a polymer having an amide bond and / or aramid paper, the molten polymer penetrates into the surface of the polymer having an amide bond and / or the aramid fibrid and / or aramid short fiber constituting the aramid paper. By impregnation, the polymer and the insulating sheet 6 are entangled at the molecular level, and the adhesion between the resin molded body 2 and the insulating sheet 6 becomes stronger. In addition, the expansion of the resin and core material 8 due to temperature changes during molding improves the adhesion between the insulating sheet 6 and core material 8, allowing the heat generated by the windings to be transferred efficiently to the core material 8, preventing excessive temperature increases, reducing copper loss in the windings, and improving motor output.

[0055] In particular, when the resin molded body 2 is formed using a polymer having an amide bond and the surface of the insulating sheet 6 in contact with the resin molded body 2 is composed of a polymer having an amide bond, or when the resin molded body 2 is formed using a polymer having an amide bond and the surface of the insulating sheet 6 in contact with the resin molded body 2 is composed of aramid paper made of aramid fibrids and aramid short fibers, the polymer having an amide bond that constitutes the resin molded body 2 and the insulating sheet 6 become entangled at the molecular level, making the adhesion between the resin molded body 2 and the insulating sheet 6 stronger.

[0056] (Action and effect) According to this embodiment, the following advantageous effects are achieved. According to this embodiment, the pair of main body parts 2a of the resin molded body 2 are integrated by the connecting part 2b, and further, the insulating sheet 6 and the resin molded body 2 are connected by abutting each other, so that the laminated core material 8 can be integrated without temporary fixing by crimping, adhesion, etc. This makes it unnecessary to provide a crimping joint for crimping in the core material 8, thereby suppressing iron loss, and does not require additional processes such as applying an adhesive or using a laser beam.

[0057] Furthermore, according to this embodiment, when the resin molded body 2 is molded, the molten resin passes through the outer peripheral groove portion 4e, the inner peripheral groove portion, or the through hole and fills the space corresponding to the pair of main body portions 2a and the connecting portion 2b, thereby making it possible to integrate the main body portion 2a and the connecting portion 2b.

[0058] Furthermore, according to this embodiment, both axial surfaces of the annular core material 8 are flat, and the flat surfaces of each core material 8 are in direct contact with the adjacent core materials 8, so that iron loss can be further suppressed.

[0059] Furthermore, in this embodiment, the insulating sheet 6 and the resin molded body 2 are connected without using an adhesive, so that the annular laminated core material 1 can be manufactured without performing additional processes such as bonding.

[0060] In addition, in this embodiment, the axial length of the contact portion between the insulating sheet 6 and the resin molded body 2 is 0.5 mm or more. Therefore, when linear segment conductors are placed in the grooves of the annular laminated core material 1 and the core materials are bent, there is no misalignment between them and the core materials can withstand the load applied when bent.

[0061] Furthermore, in this embodiment, the insulating sheet 6 and the resin molded body 2 are connected by being impregnated with the resin that constitutes the resin molded body 2 on the surface of the insulating sheet 6 that comes into contact with the resin molded body 2, thereby making it possible to connect the insulating sheet 6 and the resin molded body 2 more firmly.

[0062] Furthermore, in this embodiment, the resin molded body 2 is formed using a polymer having an amide bond, and the surface of the insulating sheet 6 that abuts the resin molded body 2 is made of a polymer having an amide bond, so that the polymer and the insulating sheet 6 become entangled at the molecular level, thereby more firmly connecting the insulating sheet 6 and the resin molded body 2.

[0063] In addition, in this embodiment, the resin molded body 2 is formed using a polymer having an amide bond, and the surface of the insulating sheet 6 that abuts the resin molded body 2 is made of aramid paper made of aramid fibrids and aramid short fibers, so that the polymer and the insulating sheet 6 are entangled at the molecular level, and the insulating sheet 6 and the resin molded body 2 can be more firmly connected. EXAMPLES

[0064] The present invention will be described below with reference to examples. Note that these examples are provided to illustrate the content of the present invention, and are not intended to limit the content of the present invention in any way.

[0065] (raw material preparation) Using a pulp particle manufacturing device (wet precipitator) consisting of a combination of a stator and a rotor, described in JP-A-52-15621, polymetaphenylene isophthalamide fibrids were manufactured. The fibrids were processed in a disintegrator and a beater to adjust the length-weighted average fiber length to 0.9 mm. The freeness of the obtained aramid fibrids was 90 cm 3 It was.

[0066] On the other hand, meta-aramid fibers (Nomex (registered trademark), single fiber fineness 2 denier) manufactured by DuPont were cut to a length of 6 mm (hereinafter referred to as "aramid short fibers").

[0067] (Aramid paper manufacturing) The prepared aramid fibrids and aramid short fibers were each dispersed in water to prepare a slurry. These slurries were mixed so that the fibrids and aramid short fibers were mixed in a 1 / 1 blend ratio (weight ratio), and then printed on a Tappy-type hand-made papermaking machine (cross-sectional area 625 cm2).2 Then, this was subjected to heat and pressure processing at a temperature of 330° C. and a linear pressure of 300 kg / cm using a metal calendar roll to obtain the aramid papers shown in Examples 1 and 2 in Table 1.

[0068] (Manufacturing of laminated sheets) An aramid paper (basis weight 37 g / m) produced in the same manner as above by the method described in paragraph

[0024] of JP 2006-321183 A was used. 2 A laminated sheet shown in Examples 3 and 4 in Table 1 containing aramid paper having a three-layer structure of aramid paper / resin composition / aramid paper (weight ratio of 37 / 54 / 37) with the aramid paper arranged on the outside was obtained using a semi-aromatic polyamide resin composition (Formulation Example 6 in JP 2006-321183 A) containing 50% by weight of an epoxy group-containing phenoxy resin and a 100% polyester resin (thickness: 51 μm, density: 0.73 g / cm3).

[0069] In addition, aramid paper (basis weight 37g / m 2 , thickness 51μm, density 0.73g / cm 3 ) and a polyethylene terephthalate film manufactured by Toray Industries, Inc. (S28♯16, thickness 16 μm) were bonded together with an adhesive to obtain laminated sheets shown in Examples 5 and 6 of Table 1, which include aramid paper having a three-layer structure of aramid paper / polyethylene terephthalate film / aramid paper (weight ratio 37 / 54 / 37) with the aramid paper arranged on the outside.

[0070] (Core material manufacturing) A non-oriented electrical steel sheet (thickness: 0.5 mm, thickness tolerance: 0.04 mm) specified in JIS C 2552 was punched into a ring shape to produce the core material 8, as shown in Fig. 2. Note that the core material 8 does not show any traces of temporary fixing means such as caulking or bonding.

[0071] (Manufacturing of annular laminated core materials) Using the aramid paper or laminated sheet manufactured as described above as the insulating sheet, the core material 8 manufactured as described above, and semi-aromatic polyamide manufactured by DuPont (ZYTEL (registered trademark) HTN51G35EF) as the polymer, insert molding was performed under the conditions shown in Table 1 to obtain an annular laminated core material 1 shown in FIG. 1. That is, (1) the core material 8 is laminated and inserted in advance into the cavity for injection molding, (2) an insulating sheet 6 is placed in the groove of the laminated core material 8, and (3) semi-aromatic polyamide manufactured by DuPont is introduced, and the resin molded body 2, the insulating sheet 6, and the laminated core material 8 are integrally molded by injection molding using a melt injection molding method. At this time, the molten polymer impregnates at least the surface portion of the insulating sheet 6, and the insulating sheet 6 is directly bonded to the surface of the resin molded body 2, so that an annular laminated core material 1 without any trace of the temporary fixing means shown in FIG. 1 can be obtained. The measurement methods for each condition are as follows.

[0072] (Measurement method)

[0073] (1) Measurement of basis weight and thickness The test was carried out in accordance with JIS C2300-2.

[0074] (2) Calculating density Calculated by dividing basis weight by thickness.

[0075] (3) Tensile strength and elongation The test was carried out in accordance with JIS C2300-2.

[0076] (4) Adhesiveness The adhesive area between the insulating paper and the resin molded body was visually inspected, and those that had no wrinkles (bulges in the insulating paper) were judged as "good," and those that had wrinkles were judged as "bad."

[0077] (5) Appearance of insulation sheet 6 The degree of warping of the insulating sheet portion due to heat during molding was judged visually.

[0078] (6) Adhesion between the insulating sheet 6 and the core material 8 Regarding the degree of adhesion between the insulating sheet portion and the core material 8, a motor bobbin containing the core material 8 was impregnated with epoxy resin, hardened, and then cut perpendicular to the axial direction at the axial midpoint of the annular laminated core material 1 using a water jet containing garnet microparticles (Omax Model 626), and the average distance between the insulating sheet 6 and the core material 8 at the cut surface was measured.

[0079] (7) Flexibility A straight segment conductor was placed in the groove of the annular laminated core material 1, and when it was bent, the misalignment between each core material was visually observed. Those with no misalignment were judged as "good", and those with misalignment were judged as "bad".

[0080] [Table 1]

[0081] From the results in Table 1, the annular laminated core material of the embodiment can withstand the load applied when the segment conductor is bent when the segment conductor is used for the winding because the outer circumferential surface is supported by the resin molded body. In addition, there is no trace of a temporary fixing means, and no iron loss occurs due to eddy currents caused by the remains of the crimped joint, and the grooves of the core material are covered with a thin insulating sheet, so high efficiency can be expected by increasing the wire area of ​​the winding. In addition, the adhesion between the insulating paper and the resin is sufficient, so the insulation breakdown voltage is sufficiently high, and furthermore, since the aramid paper and polymer used have high heat resistance, it is considered that it can withstand the heat generated by the winding, so it is useful as a motor bobbin that can withstand high efficiency and high output of motor generators, etc. In particular, in the case of the embodiment 3 and 4, the resin composition of the middle layer of the laminated sheet has a similar structure to the resin molded body, so it is considered that it softened during molding, and the adhesion between the insulating sheet and the core material was the best. Furthermore, compared to the case of JP 55-13665, in which the entire unnecessary removed thin plate portion is cut into a half-punched shape to form a crimped joint portion for temporary fastening, and this removed thin plate portion is then removed later by press punching, this method does not require a large punching force and is easy to remove, and no residual material or burrs are produced, so no post-processing is required, allowing for the production of high-quality laminated core material products with good workability. Furthermore, since the resin molded body and the insulating sheet are attached at the same time as molding, the steps of crimping and attaching the resin molded body can be omitted. [Explanation of symbols]

[0082] 1 Annular laminated core material 2. Resin molding 2a Main body 2a1 Circular ring 2a2 Arm 2a3 Protrusion 2a4 Groove 2b Connecting part 4 Core body 4a Cylindrical part 4b Arm 4c protrusion 4d groove 4e Outer groove 6 Insulation sheet 6a central part 6b Left turn 6c Right turn 6d Tip bent part 6e Bent tip 8 Core Material 8a Circular ring 8b Arm 8c protrusion 8d Groove 8e Outer periphery groove

Claims

1. An annular laminated core material, a core body formed into a cylindrical shape by laminating a plurality of annular core materials, and having an axially extending groove formed on an inner peripheral surface on the radially inner side or an outer peripheral surface on the radially outer side; a pair of body portions formed so as to cover at least a part of both axial end surfaces of the core body, and a connecting portion connecting the pair of body portions; and a resin molded body in which the pair of body portions are integrally molded. an insulating sheet disposed on an inner surface of the groove, Both axial end portions of the insulating sheet are in contact with the main body portion of the resin molded body, The core body has a through hole extending between both axial end faces, the connecting portion connects the pair of body portions through a through hole of the core body, The groove portion is open to both axial end surfaces, The insulating sheet and the resin molded body are connected to each other by impregnating a surface of the insulating sheet that contacts the resin molded body with a resin that constitutes the resin molded body. Annular laminated core material.

2. An annular laminated core material, a core body formed into a cylindrical shape by laminating a plurality of annular core materials, and having an axially extending groove formed on an inner peripheral surface on the radially inner side or an outer peripheral surface on the radially outer side; a pair of body portions formed so as to cover at least a part of both axial end surfaces of the core body, and a connecting portion connecting the pair of body portions; and a resin molded body in which the pair of body portions are integrally molded. an insulating sheet disposed on an inner surface of the groove, Both axial end portions of the insulating sheet are in contact with the main body portion of the resin molded body, a circumferential groove portion is formed on the inner circumferential surface or the outer circumferential surface of the core body, the circumferential groove portion extending between both end surfaces in the axial direction; the connecting portion passes through the circumferential groove of the core body to connect the pair of body portions, The groove portion is open to both axial end surfaces, The insulating sheet and the resin molded body are connected to each other by impregnating a surface of the insulating sheet that contacts the resin molded body with a resin that constitutes the resin molded body. Annular laminated core material.

3. The annular core member has flat surfaces on both axial surfaces, and the flat surfaces of each core member are in direct contact with the adjacent core members.

3. An annular laminated core material according to claim 1 or 2.

4. 4. The annular laminated core material according to claim 1, wherein the insulating sheet and the resin molding are connected together without using an adhesive.

5. 5. The annular laminated core material according to claim 1, wherein the axial length of the contact portion between the insulating sheet and the resin molded body is 0.5 mm or more.

6. the resin molded body is formed using a polymer having an amide bond, 6. The annular laminated core material according to claim 1, wherein the surface of the insulating sheet that is in contact with the resin molded body is made of a polymer having an amide bond.

7. the resin molded body is formed using a polymer having an amide bond, The annular laminated core material according to any one of claims 1 to 5, wherein the surface of the insulating sheet that contacts the resin molded body is made of aramid paper made of aramid fibrids and aramid short fibers.

8. A motor using a stator in which a winding is wound around the annular laminated core material according to any one of claims 1 to 7.

9. A motor generator using a stator having a winding wound around the annular laminated core material according to any one of claims 1 to 7.

10. A generator using a stator in which a winding is wound around the annular laminated core material according to any one of claims 1 to 7.

11. A method for producing an annular laminated core material, comprising the steps of: a placement step of placing the core body, which is formed into a cylindrical shape by stacking a plurality of annular core blocks and has an axially extending groove formed on an inner peripheral surface on the radially inner side or an outer peripheral surface on the radially outer side, in a molding die such that an insulating sheet is placed in the groove; a resin molding step of injecting a resin into a mold to integrally mold a resin molded body including a pair of body portions formed so as to cover at least a part of both axial end surfaces of the core body, The resin molded body is integrally formed with a pair of main body portions formed to cover at least a part of both axial end surfaces of the core body, and a connecting portion connecting the pair of main body portions, The core body has a through hole extending between both axial end faces, the connecting portion connects the pair of body portions through a through hole of the core body, In the resin molding step, the insulating sheet is disposed so that at least a portion of the insulating sheet contacts the resin molded body, and the molten polymer forming the resin molded body is impregnated into at least a surface portion of the insulating sheet, and the resin molded body is formed so that the groove portion opens to both end surfaces in the axial direction. A method for manufacturing an annular laminated core material.

12. A method for producing an annular laminated core material, comprising the steps of: a placement step of placing the core body, which is formed into a cylindrical shape by stacking a plurality of annular core blocks and has an axially extending groove formed on an inner peripheral surface on the radially inner side or an outer peripheral surface on the radially outer side, in a molding die such that an insulating sheet is placed in the groove; a resin molding step of injecting a resin into a mold to integrally mold a resin molded body including a pair of body portions formed so as to cover at least a part of both axial end surfaces of the core body, The resin molded body is integrally formed with a pair of main body portions formed to cover at least a part of both axial end surfaces of the core body, and a connecting portion connecting the pair of main body portions, a circumferential groove portion is formed on the inner circumferential surface or the outer circumferential surface of the core body, the circumferential groove portion extending between both end surfaces in the axial direction; the connecting portion passes through the circumferential groove of the core body to connect the pair of body portions, In the resin molding step, the insulating sheet is disposed so that at least a portion of the insulating sheet contacts the resin molded body, and the molten polymer forming the resin molded body is impregnated into at least a surface portion of the insulating sheet, and the resin molded body is formed so that the groove portion opens to both end surfaces in the axial direction. A method for manufacturing an annular laminated core material.

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