Coil unit, motor member, method for manufacturing coil unit, and method for manufacturing motor member

Abstract

Provided are: a motor member which has a light weight and is capable of flexibly conforming to an arbitrarily-defined shape and simplifying a manufacturing process; and a method for manufacturing the motor member. Also provided are: a coil unit capable of improving handleability when being assembled to a final product and reducing the number of components in the final product; a motor member; a method for manufacturing the coil unit; and a method for manufacturing the motor member.　A motor member 1 is composed of a resin molded body containing a soft magnetic material. A motor member 20 has a stator core 1 molded with a resin containing a soft magnetic material, and a coil 30 provided to the stator core 1.

Description

Coil unit, motor member, method of manufacturing coil unit, and method of manufacturing motor member

[0001] The present invention relates to a coil unit, a motor member, a method for manufacturing a coil unit, and a method for manufacturing a motor member.

[0002] 2. Description of the Related Art Conventionally, a stator core has been known in which split cores formed by punching and laminating electromagnetic steel sheets are combined in an annular shape (see, for example, Patent Document 1).

[0003] Also known is a configuration in which a single coil is covered with an injection-molded resin layer (see, for example, Patent Document 1). This configuration improves the ease of handling during assembly of a product (such as a motor) that uses the coil as a component, compared to a configuration in which the periphery of a spirally wound coil is covered with an insulating coating.

[0004] JP 2021-052574 A JP 2022-76171 A

[0005] However, there are limitations to how much weight can be reduced when using stator cores made of electromagnetic steel sheets. Furthermore, when dividing a stator core, as described in Patent Document 1, for example, a single divided core is formed by laminating electromagnetic steel sheets punched into the same shape, and the divided cores are then arranged in a ring shape to form the stator core, resulting in a complex and cumbersome manufacturing process. Furthermore, variations in the processing of each divided core are likely to occur, and there are limitations to the degree of freedom in the shape (processing) of the divided cores. As a result, there are problems with the miniaturization, weight reduction, and cost reduction of motors.

[0006] Furthermore, further improvements in handling are desired for mass production. Furthermore, when a large number of parts are used in assembly, there is a problem of variations in the finished product and work time depending on the skill level of the assembly worker. For this reason, there is a strong demand for reducing the number of parts in the finished product (final product).

[0007] The present invention aims to provide a motor component and a method for manufacturing a motor component that are lightweight, can be flexibly adapted to any shape, and enable a simplified manufacturing process, and also to provide a coil unit, a motor component, a method for manufacturing a coil unit, and a method for manufacturing a motor component that can improve handleability when assembling into a final product and reduce the number of parts in the final product.

[0008] The present invention relates to a motor member made of a resin molded body containing a soft magnetic material.

[0009] The present invention also relates to a motor member comprising a core molded from a resin containing a soft magnetic material, and a coil provided on the core.

[0010] The present invention also relates to a method for manufacturing a motor component, characterized by comprising the steps of: placing a coil in a mold; and injecting a resin containing a soft magnetic material into the mold to form a core.

[0011] The present invention also relates to a method for manufacturing a motor component, characterized by comprising the steps of: placing a coil in a mold; and injecting a resin containing a soft magnetic material into the mold to form a core.

[0012] The present invention also relates to a method for manufacturing a motor component, characterized by comprising the steps of: molding a plurality of teeth using a first resin containing a soft magnetic material; molding a support portion capable of integrally supporting the plurality of teeth using a second resin containing a soft magnetic material; and assembling the plurality of teeth and the support portion.

[0013] The present invention also relates to a method for manufacturing a motor component, characterized by comprising a step of injecting a resin containing a soft magnetic material into a mold and solidifying the resin.

[0014] The present invention also relates to a coil unit comprising a plurality of coils and an injection-molded resin that integrally covers the plurality of coils.

[0015] The present invention also relates to a motor member comprising the above coil unit and a core to which the coil unit is attached.

[0016] The present invention also relates to a method for manufacturing a coil unit, characterized by having a step of placing multiple coils in a mold and a step of injecting injection molding resin into the mold to integrally coat the multiple coils.

[0017] The present invention also relates to a method for manufacturing a motor component, characterized by comprising the steps of: arranging a plurality of coils in a mold; injecting injection molding resin into the mold to integrally coat the plurality of coils to form a coil unit; and assembling the coil unit and a core.

[0018] According to the present invention, it is possible to provide a motor component and a method for manufacturing a motor component that are lightweight, can be flexibly adapted to any shape, and can simplify the manufacturing process, and it is also possible to provide a coil unit, a motor component, a method for manufacturing a coil unit, and a method for manufacturing a motor component that can improve handleability when assembling into a final product and reduce the number of parts in the final product.

[0019] FIG. 1 is a schematic plan view showing an integrated stator core according to a first embodiment of the present invention. FIG. 2 is a diagram showing a combined stator core according to the first embodiment, (A) a schematic plan view and (B) an external perspective view. FIG. 3 is a diagram showing a combined stator core according to the first embodiment, (A) a schematic plan view, (B) a side view, and (C) a side view. FIG. 4 is a schematic plan view showing a stator according to the first embodiment. FIG. 5 is a diagram explaining a molded coil according to the first embodiment, (A) an external perspective view, (B) a sectional view, (C) an external perspective view, (D) a sectional view, and (E) a sectional view. FIG. 6 is a flowchart explaining a first manufacturing method of the stator according to the first embodiment. FIG. 7 is a diagram explaining a manufacturing method of the stator according to the first embodiment. FIG. 8 is a diagram explaining a manufacturing method of the stator according to the first embodiment. FIG. 9 is a diagram explaining a manufacturing method of the stator according to the first embodiment. FIG. 10 is a flowchart explaining a second manufacturing method of the stator according to the first embodiment. FIG. 11 is a diagram explaining a manufacturing method of the stator according to the first embodiment. FIG. 12 is a diagram explaining a manufacturing method of the stator according to the first embodiment. FIG. 13 is a diagram explaining a manufacturing method of the stator according to the first embodiment. FIG. 14 is a diagram explaining a manufacturing method of the stator according to the first embodiment. FIG. 1 is a diagram showing characteristics of a stator according to the first embodiment. FIG. 2 is a diagram showing characteristics of a stator according to the first embodiment. FIG. 3 is a schematic plan view illustrating a coil unit according to a second embodiment of the present invention. FIG. 4 is a diagram illustrating a coil unit according to the second embodiment, where (A) is an external perspective view of the coil, (B) is a cross-sectional view of the coil, and (C) is a cross-sectional view of the coil unit. FIG. 5 is a schematic plan view illustrating a method for manufacturing the coil unit according to the second embodiment. FIG. 6 is a diagram illustrating a stator core according to the second embodiment, where (A) is a schematic plan view and (B) is an external perspective view. FIG. 7 is a schematic plan view illustrating a method for manufacturing a stator according to the second embodiment. FIG. 8 is a schematic plan view illustrating a method for manufacturing a stator according to the second embodiment. FIG. 9 is a diagram illustrating a stator core according to the second embodiment, where (A) is a schematic plan view and (B) is a side view.FIG. 1 is a plan view schematic diagram illustrating a method for manufacturing a stator according to a second embodiment. FIG. 2 is a plan view schematic diagram illustrating a stator core according to a second embodiment, (A) a plan view schematic diagram, (B) a developed side view, (C) a plan view schematic diagram, and (D) a plan view schematic diagram. (A) a plan view schematic diagram illustrating a method for manufacturing a stator according to a second embodiment, (B) a plan view schematic diagram illustrating a stator core according to a second embodiment. FIG. 3 is a plan view schematic diagram illustrating a method for manufacturing a stator according to a second embodiment. FIG. 4 is a plan view schematic diagram illustrating a method for manufacturing a stator according to a second embodiment.

[0020] <<First Embodiment>> A first embodiment of the present invention will be described in detail below with reference to FIGS. 1 to 19. The first embodiment relates to a motor member and a manufacturing method thereof. The following description will be given, as an example, of a motor member being a stator core 1 or a stator 20. <Stator Core> FIGS. 1 to 3 are external views showing an example of a stator core 1 according to the first embodiment. The stator core 1 according to the first embodiment is a resin molded body molded from a resin containing a soft magnetic material. Specifically, the stator core 1 (resin molded body) is obtained by thermally melting resin pellets containing a kneaded soft magnetic material, injecting the resin pellets into a mold of the desired shape, and then cooling and solidifying the resin. The soft magnetic material is present in a greater volume ratio (content ratio) than the resin (pellets). The soft magnetic material is, for example, permendur.

[0021] In the following description, stator core 1 is a collective term for integrated stator cores 1A and 1B (see FIG. 1) and combined stator cores 1C, 1D, and 1E (see FIGS. 2, 3, and 10, respectively). Integrated stator cores 1A and 1B are stator cores 1 formed as a single member, each having a plurality of annularly arranged teeth 3 and 5 integrally supported by support portions 2 and 4. Combined stator cores 1C, 1D, and 1E are stator cores 1 formed from a plurality of split cores 11, 14, and 19, respectively.

[0022] Fig. 1 is a schematic plan view showing an example of an integrated stator core 1A, 1B. Fig. 1(A) shows an integrated stator core 1A used in, for example, an inner rotor type motor, which is configured integrally (inseparably) with a cylindrical (annular) support portion 2 and a plurality of teeth 3. The plurality of teeth 3 are arranged at equal intervals in the circumferential direction of the support portion 2, which is substantially annular in plan view, and protrude radially inward from the support portion 2. A coil (not shown here) is attached to each tooth 3.

[0023] 1(B) shows an integrated stator core 1B used in, for example, an outer rotor type motor, which is configured integrally (inseparably) with a cylindrical (disk)-shaped support portion 4 and a plurality of teeth 5. The plurality of teeth 5 are arranged at approximately equal intervals in the circumferential direction of the support portion 4, which is approximately annular in plan view, and protrude radially outward from the support portion 4. A coil (not shown here) is attached to each tooth 5.

[0024] FIG. 2 shows a combined stator core 1C, with (A) being a schematic plan view of the combined stator core 1C and (B) being an external perspective view of one split core 11. The combined stator core 1C is composed of multiple split cores 11 that are roughly T-shaped in plan view. The multiple split cores 11 have the same shape, each with an arc portion 13 and teeth 12 protruding radially inward from the arc portion 13. The arc portions 13 of the multiple split cores 11 are then lined up and connected in the arc length direction to form the combined stator core 1C, in which multiple teeth 12 are arranged in an annular shape. In this case, the arc portions 13 can also be considered connecting portions. Even when multiple split cores 11 are formed with the same shape, resin-molded split cores 11 can be mass-produced more easily and with less shape variation than stator cores formed by laminating electromagnetic steel sheets.

[0025] 3A is a diagram showing a combined stator core 1D, in which (A) is a schematic plan view of the combined stator core 1D, and (B) and (C) are diagrams showing a state in which the split cores 14 are assembled into the combined stator core 1D, and are side views of the generally annular combined stator core 1D as seen from the circumferential direction in the plan view of (A).

[0026] The combined stator core 1D is composed of a plurality of split cores 14 that are roughly I-shaped in plan view and cylindrical (annular) support portions (connecting portions) 16. The split cores 14 and the support portions 16 are constructed separately. Each split core 14 has wedge-shaped protrusions 15 at one radial end (the radially inner side) of the support portions 16, and the outer peripheral surface of the support portions 16 has recesses 17 that conform to the shape of the protrusions 15 and are equally spaced circumferentially. In other words, the protrusions 15 and the recesses 17 are engageable, and this engagement causes the split cores 14 to become teeth 18 that protrude radially outward from the outer peripheral surface of the support portions 16.

[0027] 3B and 3C, the split cores 14 (teeth 18) are attached to the support portions 16 by aligning the convex portions 15 of the split cores 14 with the concave portions 17 of the support portions 16 above and below in the central axis direction of the substantially annular (cylindrical) support portions 16, and then inserting and fixing them together. In this case, the wedge-shaped convex portions 15 of the split cores 14 and the concave portions 17 of the support portions 16 can be inserted and slide vertically, but a clearance is set so that rattle does not occur after engagement.

[0028] As described above, the stator core 1 of the first embodiment is a resin molded body formed by injection molding, and therefore can be molded into any shape, even complex shapes, depending on the mold, not limited to the shapes shown in the drawings of the first embodiment. Furthermore, because the resin molded body contains resin in part, it can be made lighter than conventional stator cores made entirely of metal members such as electromagnetic steel sheets.

[0029] 4 to 17, an example of a stator 20 (20A to 20J) according to the first embodiment will be described. The stator 20 according to the first embodiment includes a stator core 1 molded from a resin containing a soft magnetic material (a resin molded body), and coils 30 provided on teeth (e.g., teeth 3, 5, 12, 18, 191, etc.) of the stator core 1.

[0030] Figure 4 is a diagram illustrating an example of a stator 20 (20A), where (A) is a schematic plan view of the stator 20A, and (B) is a schematic plan view of one coil unit 21 that constitutes the stator 20A.

[0031] A stator 20A shown in FIG. 4 has the combined type stator core 1C (plurality of split cores 11) shown in FIG. 2 and coils 30 provided around the teeth 12 thereof.

[0032] The coil 30 has a molded structure in which a spiral structure made of a conductor is covered with an injection-molded resin layer (which can also be called injection-molded resin, as in the first embodiment) 312. Hereinafter, a coil having this molded structure will be referred to as a molded coil 300 (301, 302, 303). The injection-molded resin layer 312 is made of a resin different from the stator core 1 (for example, polyphenylene sulfide (PPS), liquid crystal polymer / liquid crystal plastic (LCP), nylon, etc.).

[0033] 4(B), the teeth 12 of a roughly T-shaped split core 11 are inserted into the center of the molded coil 300 (301) to form one coil unit 21. A plurality of these coil units 21 are then arranged in the arc length direction of the arc portion 13 of the split core 11 to form the stator 20A (FIG. 4(A)).

[0034] Figure 5 is a diagram illustrating the molded coil 301 shown in Figure 4. Figure 5(A) is an external perspective view of the molded coil 301, and Figure 5(B) is a cross-sectional view taken along line x-x in Figure 5(A). Figures 5(C) to 5(E) are schematic diagrams showing an example of a manufacturing method for the molded coil 301, with Figure 5(C) being an external perspective view corresponding to Figure 5(A), and Figures 5(D) and 5(E) being cross-sectional views corresponding to Figure 5(B).

[0035] The molded coil 301 includes a spiral structure 311 made of a conductor, and an injection-molded resin layer 312 that is in direct contact with and covers the spiral structure 311 (conductor).

[0036] 5(A) and 5(C), the coil 30 has a helical structure 311 formed from a conductor, and except for an end portion TS, the entire structure is integrally covered with an injection-molded resin layer 312. As an example of the helical structure 311 shown here, a so-called concentrated winding coil is shown in which winding regions CR of one turn of the helix roughly overlap in the axial direction of the helix.

[0037] As shown in Figure 5 (B) , the molded coil 301 has injection-molded resin layers 312 arranged between the winding regions CR (in the gaps G), and the multiple overlapping winding regions CR in the spiral axis direction are insulated from each other by the injection-molded resin layers 312.

[0038] An example of a manufacturing method for the molded coil 301 will be described. First, as shown in FIGS. 5(C) and 5(D), a helical structure 311 is formed from a conductor (e.g., a metal conductor mainly composed of copper and / or aluminum). The helical structure 311 is formed, for example, by preparing multiple strip-shaped (e.g., U-shaped) flat conductors (coil pieces) and joining them by butting and pressing their longitudinal end faces together. However, this is not a limitation, and any manufacturing method for the helical structure 311 can be used. For example, the helical structure 311 may be formed by butting and pressing the end faces of multiple strip-shaped round wire conductors together. The helical structure 311 may also be formed by winding a long flat conductor wire (without splicing) or a long round wire conductor wire (without splicing). The helical structure 311 may also be formed by winding a long round wire conductor wire into a spiral shape and then pressing it in the spiral axis direction to form a flat conductor wire. However, in either case, the spiral structure 311 is made of a conductor itself and is not covered with an insulating coating (it is an insulating coating-less conductor).

[0039] Then, as shown in FIG. 11E, the spiral structure 311 is covered with an injection-molded resin layer 312 while maintaining a gap G of a distance P between the circumferential regions CR.

[0040] In this case, for example, the spiral structure 311 is pre-formed so that the orbital regions CR are spaced apart by a predetermined distance P. In FIG. 5E, all of the orbital regions CR are spaced apart by approximately the same distance P. In this case, FIGS. 5D to 5E show an example in which the spiral structure 311 is formed so that the orbital regions CR are expanded to the distance P. However, the spiral structure 311 generally has varying distances between the orbital regions CR immediately after formation, and the method is not necessarily limited to expanding to the distance P. In other words, the spiral structure 311 is formed so that the orbital regions CR are expanded or contracted to achieve an approximately uniform distance P. The distance P can be ensured approximately uniformly, for example, by a spacer member (not shown) provided integrally with or separate from the spiral structure 311. However, the distance P may also be ensured by elastic deformation and / or plastic deformation without using a spacer member.

[0041] The helical structure 311 is then placed in a predetermined injection molding die (mold forming die). Molten resin (e.g., PPS, LCP, nylon, etc.) is then injected and solidified to form the injection-molded resin layer 312. This results in the molded coil 301 shown in FIGS. 5A and 5B. Alternatively, the injection-molded resin layer 312 may be formed without molding the helical structure 311 in advance by providing a spacer in the mold forming die to separate the winding regions CR by a predetermined distance P, thereby separating the winding regions CR of the helical structure 311.

[0042] In this way, the molded coil 301 of the first embodiment is entirely covered integrally with the injection-molded resin layer 312. As shown in FIG. 5B , the periphery of the helical structure 311 is in direct contact with the injection-molded resin layer 312 (without an insulating coating), and the multiple overlapping winding regions CR in the helical axis direction are insulated by the injection-molded resin layer 312. The winding regions CR are fixed by the injection-molded resin layer 312 with a distance P maintained between them. In this way, the molded coil 301 does not have an insulating coating covering the conductor, and the conductor is insulated by the injection-molded resin layer 312. The distance P may be any value, but should be large enough to allow the injection-molded resin to reliably penetrate between the winding regions CR and insulate the winding regions CR from each other.

[0043] 6 is a flowchart showing an example of the flow of a first manufacturing method for the stator 20 according to the first embodiment. The manufacturing method for the stator 20 includes a step of preparing the spiral structure 311 (step S01), a step of forming the molded coil 300 (step S03), a step of setting the molded coil 300 in the core molding die 202 (step S05), and a step of molding a resin molded body that constitutes the stator core 1 (step S07).

[0044] The first manufacturing method of the stator 20 will be specifically described with reference to Fig. 7. Fig. 7 is a schematic diagram showing a process of forming one coil unit 21 shown in Fig. 4(B) by the first manufacturing method to form the stator 20A.

[0045] First, as shown in FIG. 7A, a helical structure 311 is formed using a conductor (step S01 in FIG. 6). Then, with the winding regions CR of the helical structure 311 spaced apart by a predetermined distance P, the helical structure 311 is placed in a molding die 201 as shown in FIG. 7B. Alternatively, the distance P between the winding regions CR is maintained and secured within the molding die 201. Then, a pellet of resin (e.g., PPS, LCP, nylon, etc.) is melted by heat, injected into the molding die 201, and cooled and solidified. This forms a molded coil 301 in which the helical structure 311 is covered with an injection-molded resin layer 312, except for the end portions TS, as shown in FIG. 7C (step S03 in FIG. 6).

[0046] Thereafter, as shown in Fig. 7(D), the molded coil 301 is placed in another injection mold (core molding die 202) (step S05 in Fig. 6). Then, resin pellets mixed with a soft magnetic material are melted by heat, injected into the core molding die 202, and cooled and solidified. This results in, for example, a roughly T-shaped split core 11 (a resin molded body that constitutes the stator core 1) being molded as shown in Fig. 7(E) (step S07 in Fig. 6). That is, in the first manufacturing method, the split core 11 is molded later by injection molding a resin mixed with a soft magnetic material into the molded coil 301, and the molded coil 301 is attached to the teeth 12.

[0047] In this case, the injection molding temperature (melting temperature of the resin pellets) in the core molding die 202 is set to a temperature (e.g., 350 to 450°C) that does not cause the injection-molded resin layer 312 of the molded coil 301 to re-melt (hereinafter, the melting temperature of the resin pellets is the same as in the first manufacturing method).

[0048] This forms a coil unit 21 (FIGS. 7(E) and 4(B)), in which the teeth 12 of the split core 11 and the molded coil 301 are integrated. The stator 20A shown in FIG. 4(A) is formed by arranging the coil units 21 in a ring shape. The multiple helical structures 311 (coils 30) are appropriately connected by wiring members (such as bus bars) (not shown). Conventionally, helical structures (coils) with insulating coatings have been attached to teeth via insulating materials (such as insulating paper). However, helical structures are flexible, and when attached to teeth, overlapping winding regions in the helical axis direction may shift, resulting in poor handling or scratches on the thin insulating coating, degrading the withstand voltage. According to the first embodiment, the molded coil 301 insulates the winding regions CR of the helical structure 311 and fixes its shape, significantly improving handling when attached to the teeth 12. Furthermore, deterioration of withstand voltage due to exposed conductors can be avoided. Furthermore, since the molded coil 301 and the teeth 12 can be integrated, the handling when assembling the stator 20A is improved, and the work efficiency can be improved.

[0049] Fig. 8 is a schematic plan view showing another example of the stator 20. The stator 20 (20B) shown in Fig. 8 has a coil 30 (molded coil 302) and a stator core 1, as shown in Fig. 8(D).

[0050] The coil 30 shown in Fig. 7 is a molded coil 301 in which a single spiral structure 311 is covered with an injection-molded resin layer 312, but the coil 30 in Fig. 8 is a molded coil 302 in which a plurality of spiral structures 311 are arranged in an annular shape and are integrally covered with an injection-molded resin layer 312. In addition, the shape of the stator core 1 in this case is, for example, the integrated stator core 1A shown in Fig. 1(A).

[0051] The manufacturing method of the stator 20B shown in Fig. 8 is the same as the first manufacturing method (Fig. 6) described above. First, as shown in Fig. 8(A), a plurality of (all of the spiral structures 311 constituting the stator 20B) insulating coating-free spiral structures 311 are arranged in a ring shape in the molding die 201 with a predetermined distance P between each of the spiral structures 311 and each of the spiral structures 311 being maintained between their respective circumferential regions CR (Fig. 6: step S01).

[0052] 8(B), molten resin (e.g., PPS, LCP, nylon, etc.) is injected into molding die 201 and solidified to form injection-molded resin layer 312 (FIG. 6: step S03). This results in an annular molded coil 302 that integrally covers multiple helical structures 11 with injection-molded resin layer 312. Similar to molded coil 301 shown in FIG. 5, molded coil 302 has injection-molded resin layer 312 embedded between multiple overlapping winding regions CR in the helical axis direction in each helical structure 311, thereby providing insulation. Furthermore, the winding regions CR are fixed by injection-molded resin layer 312 while maintaining distance P between them.

[0053] Thereafter, as shown in Fig. 8(C), annular molded coil 302 is placed in core-molding die 202 (Fig. 6: step S05). Resin pellets kneaded with a soft magnetic material are melted by heat and injected into core-molding die 202, after which they are cooled and solidified to form integrated stator core 1A as a resin-molded body as shown in Fig. 8(D) (Fig. 6: step S07). In this way, stator 20B is formed in which annular molded coil 302 is attached to teeth 3 (teeth 3 and annular molded coil 302 are integrated).

[0054] Because the integrated stator core 1A can be molded from resin, it is possible to attach an annular molded coil 302 to the integrated stator core 1A for the inner rotor. In this case, work efficiency can be improved compared to a configuration in which a single coil 30 (molded coil 300) is attached to each tooth 12 (for example, a configuration in which a coil (molded coil 300) is attached to a split core 11 and the split core 11 is joined).

[0055] Although not shown, the spiral structures 311 (coils 30) are connected to each other by wiring members (bus bars). The connection of the coils 30 may be performed before the injection-molded resin layer 312 shown in Fig. 8A is formed, or after the injection-molded resin layer 312 shown in Fig. 8B is formed and before the stator core 1A is formed, or after the stator 20B is formed.

[0056] FIG. 9A is a schematic plan view showing another stator 20. This stator 20 (20C) has a configuration in which an annular molded coil 302 as shown in FIG. 8 is attached to the integrated stator core 1B for an outer rotor shown in FIG. 1B. The manufacturing method of this stator 20C is the same as that of the stator 20B in FIG. 8 except for the shape of the integrated stator core 1B and the relative arrangement of the integrated stator core 1B and the molded coil 302, so a description thereof will be omitted. Because the integrated stator core 1B can be molded from resin, the annular molded coil 302 can be attached even to the integrated stator core 1B for an outer rotor. In this case, too, work efficiency can be significantly improved compared to a configuration in which a single coil 30 (molded coil 300) is attached to each tooth 12.

[0057] FIG. 9B is a schematic plan view of yet another stator 20. This stator 20 (20D) includes multiple molded coils 301, each of which has a spiral structure 311 covered with an injection-molded resin layer 312, and the integrated stator core 1A shown in FIG. 1A. The manufacturing method for this stator 20D is similar to the first manufacturing method. Specifically, the spiral structure 311 is prepared (FIG. 6: step S01), and the multiple molded coils 301 are individually covered with an injection-molded resin layer 312 to form the multiple molded coils 301 (FIG. 6: step S03). These are then annularly arranged in the core molding die 202 (FIG. 6: step S05). Resin pellets containing a kneaded soft magnetic material are then melted by heat and injected into the core molding die 202, after which they are cooled and solidified to form the integrated stator core 1A (FIG. 6: step S07). This results in the formation of the stator 20D, in which the molded coils 301 (coils 30) are integrally attached to the teeth 3.

[0058] FIG. 10 is a diagram showing another example of the stator 20. The stator 20 (20E) in this example is configured with another coil unit 22 consisting of a molded coil 303 and a divided core 19. The manufacturing method of the stator 20E (coil unit 22) in this case is the same as the first manufacturing method described above. First, as shown in FIG. 10A, a plurality of (three in this example) spiral structures 311 electrically connected to each other by, for example, wiring members W are prepared ( FIG. 6 : step S01), and these are integrally covered with an injection-molded resin layer 312 to form the molded coil 303 shown in FIG. 10B ( FIG. 6 : step S03). In this case, for example, three coils 30 (spiral structures 311) constituting the U-phase, V-phase, and W-phase of a three-phase motor may be integrally molded.

[0059] The number of coils 30 (spiral structures 311 ) included in the molded coil 303 in this example is two or more and is less than the total number constituting the stator 20 .

[0060] Then, as shown in Fig. 10(C), the molded coil 303 is placed in the core-molding die 202 (Fig. 6: step S05), and resin pellets containing a kneaded soft magnetic material are melted by heat and injected into the core-molding die 202. The pellets are then cooled and solidified to form the split core 19 (resin molded body) shown in Fig. 10(D) (Fig. 6: step S07). The split core 19 in this example has a configuration in which multiple (three in this example) teeth 191 corresponding to the number of coils 30 (spiral structures 311) integrated by the injection-molded resin layer 312 are integrally supported by arc-shaped support portions 192. Furthermore, by forming the split core 19, the coil unit 22 is formed by integrally combining the molded coil 303 and the split core 19.

[0061] 10(E), a plurality of sets of the coil units 22 are arranged in the arc length direction of the split core 19 (some are not shown), to form a stator 20E. The stator core 1 formed by the split core 19 is also a combined type stator core.

[0062] 10(F) is a diagram showing yet another coil unit 23. The coil unit 23 is formed by arranging a plurality of molded coils 301, each of which has a spiral structure 311 covered with an injection-molded resin layer 312, in a core molding die 202 to form a split core 19.

[0063] Although the example shown in FIG. 10 shows three spiral structures 311 electrically connected to each other, they do not necessarily have to be electrically connected to each other.

[0064] The shape of the stator core 1 is not limited to the above example, and for example, a combined type stator core 1D having a roughly I-shaped divided core 14 as shown in FIG. 3 can be used in the same manner.

[0065] The stator core 1 of the first embodiment is formed from a resin containing a soft magnetic material, thereby enabling significant weight reduction compared to conventional stator cores made from metal materials such as electromagnetic steel sheets. Furthermore, because it can be formed by injection molding, complex shapes and shapes that were previously difficult to achieve can be easily realized. For example, in a conventional stator core similar to the integrated stator core 1A shown in FIG. 1(A) formed from electromagnetic steel sheets or the like, attaching (or winding) coils to the teeth can sometimes result in interference between the coils, making attachment to the teeth impossible (or extremely difficult). According to the first embodiment, the stator core 1 can be formed by injection molding. In other words, the stator core 1 can be formed after the coil 30 (molded coils 301, 302) is placed in a mold. Therefore, even an inner rotor type stator 20B, as shown in FIG. 8, can be constructed as an integrated stator core 1A. The integrated stator core 1A (1B) eliminates the need for assembling the split cores 11, 14, simplifying and streamlining the manufacturing process and operations.

[0066] Furthermore, in the case of the molded coils 301 to 303 of the first embodiment, the process of attaching insulating materials (insulating paper, insulating resin materials) placed between the coil and the teeth, which was necessary in the assembly of conventional stators, is not necessary. Also, because the winding regions CR of the coil 30 are fixed to each other, misalignment and expansion / contraction between the winding regions CR can be prevented. In other words, handling of the coil 30 itself during the manufacture of the stator 20 is also made easier, which improves the efficiency of the manufacturing process and reduces component costs.

[0067] Furthermore, the winding regions CR of the coil 30 are insulated from each other by the injection-molded resin layer 312, eliminating the need for an insulating coating process for the coil 30. When applying an insulating coating to the coil 30 (copper wire), thorough film thickness control is required, and even with film thickness control, it is nearly impossible to completely eliminate the occurrence of pinholes, making it difficult to simplify the manufacturing process and reducing yield. The molded coils 301 to 303 of the first embodiment do not require an insulating coating process, which simplifies the manufacturing process and improves yield.

[0068] On the other hand, instead of the molded coils 301 to 303 in the above embodiment, a coil 30 having an insulating coating on a conductor (helix structure 311) may be used.

[0069] 11 is a perspective view showing an external appearance of another example of the stator 20. The stator 20 (20F) of this example has the integrated stator core 1A shown in FIG. 1 and coils 30 with insulating coatings.

[0070] As shown in Figure 11 (A) , the coil 30 in this example is formed by preparing, for example, a plurality of strip-shaped (e.g., U-shaped) flat conductors (coil pieces), butting and pressing the longitudinal end faces of the strips together to form a helical structure 311, and then forming an insulating coating around the conductor. Alternatively, the helical structure 311 is formed by winding a conductor wire (flat conductor or round wire conductor) with an insulating coating. A plurality of such coils 30 are arranged in a ring shape within a core molding die (not shown). The "coil 30 with an insulating coating" in the first embodiment refers to a coil in which the conductor constituting the helical structure 311 is covered with an insulating coating, i.e., when the conductor is viewed as a single continuous elongated member, the elongated member is continuously covered with an insulating coating.

[0071] The resin pellets containing the soft magnetic material are melted by heat and injected into a core molding die, after which they are cooled and solidified, thereby forming the stator 20F in which the coils 30 are attached to the teeth 3 of the integrated stator core 1A.

[0072] 11, the number of coils 30 with insulating coating placed in the core molding die may be a number less than the total number constituting the stator 20 (for example, three), or may be one. In other words, the coil units 21 and 22 shown in FIG. 7 or FIG. 10 may be formed.

[0073] 12 is a flowchart showing an example of the flow of another manufacturing method (second manufacturing method) of stator 20 according to the first embodiment. The second manufacturing method of stator 20 includes a step of preparing helical structure 311 (step S11), a step of forming molded coils 301 to 303 (step S13), a step of separately molding a resin molded body that constitutes stator core 1 using single core molding die 204 (step S15), and a step of assembling the resin molded body and molded coils 301 to 303 (step S17).

[0074] The manufacturing method (second manufacturing method) of the stator 20 will be specifically described with reference to Fig. 13. Fig. 13 is a schematic diagram showing a case where one coil unit 21 constituting the stator 20A shown in Fig. 4 is formed by the second manufacturing method.

[0075] First, as shown in FIGS. 13A to 13C, the spiral structure 311 is placed in the molding die 201 and covered with an injection molding resin layer 312 to form the molded coil 301 (FIG. 12: steps S11 and S13).

[0076] 13(D) and 13(E), resin pellets kneaded with a soft magnetic material are separately melted by heat and injected into a single core molding die 204, after which they are cooled and solidified to form, for example, a roughly T-shaped split core 11 (resin molded body) (FIG. 12: step S15). In this case, since the molded coil 301 and the split core 11 are molded separately, the molding temperature of the split core 11 is not limited by the melting temperature of the injection-molded resin layer 312 of the molded coil 301 (the same applies to the second manufacturing method below).

[0077] 13(F), the molded coil 301 is assembled to the teeth 12 of the split core 11 to form the coil unit 21 (FIG. 12: step S17). A plurality of these are arranged in an annular shape to form the stator 20A (FIG. 4(A)).

[0078] 14 is a schematic plan view showing another stator 20. The stator 20 (20G) of this example has an annular molded coil 302 and a stator core 1 (combined stator core 1A). The stator 20G is formed by the second manufacturing method described above.

[0079] 14A and 14B, a plurality of spiral structures 311 are prepared, and these are integrated to form an annular molded coil 302 (FIG. 12: steps S11 and S13). The method for forming the molded coil 302 is the same as in the above-described embodiment, and therefore a description thereof will be omitted.

[0080] Separately, as shown in Figures 14(C) and 14(D), resin pellets kneaded with soft magnetic material are melted by heat and injected into a single core molding die 204, after which they are cooled and solidified to form, for example, an approximately T-shaped split core 11 (resin molded body) (Figure 12: step S15).

[0081] Thereafter, as shown in FIG. 14(E), the teeth 12 of the split core 11 are attached to the center of each spiral structure 311 of the molded coil 303 to form the stator 20G (FIG. 12: step S17).

[0082] 15 is a schematic plan view showing another stator 20. The stator 20 (20H) of this example has a plurality of molded coils 301 and a stator core 1 (for example, a combined-type stator core 1B). The stator 20H is formed by the second manufacturing method described above.

[0083] First, as shown in Fig. 15(A), a plurality of spiral structures 311 are prepared, and an injection-molded resin layer 312 is provided on each of them to form a plurality of molded coils 301 (Fig. 12: steps S11 and S13). Separately, as shown in Fig. 15(B) and Fig. 15(C), an integrated stator core 1B is formed using a single-core molding die 204 (Fig. 12: step S15). Thereafter, as shown in Fig. 15(D), the molded coils 301 are respectively assembled to the teeth 5 of the integrated stator core 1B (Fig. 12: step S17), thereby forming the stator 20H.

[0084] In particular, in the case of an outer rotor type, a molded integrated stator core 1B can be used when there is no interference between adjacent molded coils 301. Also, in Fig. 15, separately molded combined stator cores 1C and 1D may be used instead of the integrated stator core 1B.

[0085] 4A may be formed by the second manufacturing method, in which the split core 11 is separately molded using a single core molding die 204 and then assembled with the molded coil 301.

[0086] 16 is a plan view showing yet another stator 20. The stator 20 (20I) of this example has another coil unit 23 made up of a molded coil 301 and a split core 11. This stator 20I can also be formed by the second manufacturing method described above.

[0087] First, as shown in Figures 16(A) and 16(B), a plurality of (here, three) spiral structures 311 electrically connected to each other by wiring members W are prepared, and each is individually covered with an injection-molded resin layer 312 to form a molded coil 301 (Figure 12: steps S11 and S13).

[0088] 16(C) and 16(D), resin pellets kneaded with a soft magnetic material are separately melted by heat and injected into a single core molding die 204, after which they are cooled and solidified to form, in this example, approximately T-shaped split cores 11 (resin molded bodies) (FIG. 12: step S15).

[0089] Thereafter, as shown in Fig. 16(E), the molded coils 301 are respectively assembled to the teeth 12 of the split core 11 to form the coil unit 23 (Fig. 12: step S17). Then, as shown in Fig. 16(F) (some parts are not shown), a plurality of coil units 23 are arranged in an annular shape to form the stator 20I.

[0090] In this case, each coil 30 of the coil units 23 is individually covered with an injection-molded resin layer 312, and the stator core 1 is a combined stator core 1C (split core 11). Therefore, as shown in FIG. 1D, the coils 30 of a certain set of coil units 23A can be arranged between the coils 30 of another set of coil units 23B. Note that the coils 30 of the coil units 23 do not need to be electrically connected to each other. The stator core 1 may also be a combined stator core 1D as shown in FIG. 3.

[0091] The stator core 1 may also be a combined stator core consisting of split cores 19 as shown in Figure 10, but in that case, it is not possible to arrange a set of coils 30 between other sets of coils 30 as shown in Figure 16 (F).

[0092] Furthermore, if there is no interference between the molded coils 301, the integrated stator cores 1A and 1B may be used.

[0093] In addition, instead of the molded coil 301 individually covered with the injection-molded resin layer 312, a configuration may be used in which a molded coil 303 provided with an injection-molded resin layer 312 integrally covering a plurality of spiral structures 311 shown in Figure 10 (B) is assembled with a separately molded divided core 19.

[0094] 17 is a plan view showing yet another stator core 1 and stator 20. The stator core 1 is formed of a resin containing a soft magnetic material, but in one stator core 1, the volume ratio of the soft magnetic material to the resin (the content ratio of the soft magnetic material) may be different between an area where the magnetic flux density is relatively high and an area where the magnetic flux density is relatively low.

[0095] Specifically, in the stator core 1, the connecting portions (the arc portions 13 shown in FIG. 2 or the support portions 16 shown in FIG. 3) generally have a lower magnetic flux density than the teeth 12. In other words, the volume ratio (content ratio) of the soft magnetic material is made higher in the tooth 12 portion, and lower in the connecting portions (the arc portions 13 or the support portions 16). This makes it possible to reduce the weight of the stator core 1 as a whole while suppressing deterioration in characteristics.

[0096] In this case, for example, as shown in Figure 17 (A), in a combined stator core 1D (see Figure 3), the multiple approximately I-shaped split cores 14 are molded from a first soft magnetic material-containing resin M1 having a high volume ratio (content ratio) of soft magnetic material, and the annular support portion 16 is molded from a second soft magnetic material-containing resin M2 having a low volume ratio (content ratio) of soft magnetic material.

[0097] The manufacturing method of this stator core 1 includes a step of molding a plurality of teeth 12 using a first soft magnetic material-containing resin M1, a step of molding a support portion 16 capable of supporting the plurality of teeth using a second soft magnetic material-containing resin M2, and a step of assembling the plurality of teeth 12 and the support portion.

[0098] Furthermore, when manufacturing a stator 20 using this stator core 1, a process of attaching coils 30 to each of the plurality of teeth 12 is included. In this case, the coils 30 may be attached to the plurality of teeth 12 in advance, and then these may be assembled to the support portion 16, or the plurality of teeth 12 may be assembled to the support portion 16, and then the coils 30 may be attached to the teeth 12.

[0099] Specifically, a method for manufacturing the stator 20 (20J) using the molded coil 301 (300) will be described with reference to FIGS. 17(B) and 17(C).

[0100] 17(B) shows a method for forming the coil 30 and teeth 12 by the first manufacturing method. In this case, first, molded coil 300 is formed. Molded coil 300 is formed by placing helical structure 311 in molding die 201 (see FIG. 7(B)), injecting resin into molding die 201, and cooling and solidifying it to form injection-molded resin layer 312.

[0101] The molded coil 301 is then placed in another injection molding die (a core molding die 202 for the teeth 12, see FIG. 7(D)). A first soft magnetic material-containing resin M1 is then injected into the core molding die 202 and cooled to solidify. The first soft magnetic material-containing resin M1 is obtained by thermally melting resin pellets in which the soft magnetic material is kneaded at a first content ratio. This results in a coil unit 21 in which the approximately I-shaped split cores 11 (teeth 12) and the molded coil 300 are integrally molded, as shown in FIG. 17(B).

[0102] Separately, a second soft magnetic material-containing resin M2 is injected into a core molding die 202 (see FIG. 7D) for the support portion 16, and then cooled and solidified. The second soft magnetic material-containing resin M2 is obtained by thermally melting resin pellets in which the soft magnetic material is mixed at a second content ratio lower than the first content ratio. Then, a plurality of teeth 12 (coil units 21) are assembled to the support portion 16 to form the stator 20J.

[0103] Fig. 17(C) shows a method of forming the stator core 1D by the second manufacturing method. In this case, the stator core 1D is molded separately from the molded coil 301. That is, a first soft magnetic material-containing resin M1 is injected into a core molding die 202 (see Fig. 7(D)) for the teeth 12, and then cooled and solidified. The first soft magnetic material-containing resin M1 is the same as that described in Fig. 17(B).

[0104] Separately, a second resin M2 containing a soft magnetic material is injected into a core molding die 202 (see FIG. 7D) for the support portion 16, and is cooled and solidified. The second resin M2 containing a soft magnetic material is the same as that described in FIG. 17B.

[0105] Thereafter, the teeth 12 are attached to the support portions 16 to form the stator core 1D.

[0106] 17B, ​​molded coils 301 are formed separately and attached to the respective teeth 12. In this way, the stator 20J is formed.

[0107] Alternatively, the molding of the teeth 12 and the support portion 16 and the formation of the molded coil 301 may be performed in separate (independent) processes, and the teeth 12 with the molded coil 301 attached may be assembled to the support portion 16 to form the stator 20J.

[0108] Note that Fig. 17 has been described using the combined stator core 1D as an example. However, although it is more difficult, this may also be applied to the combined stator core 1C shown in Fig. 2. That is, in the split core 11, the volume ratio of the soft magnetic material may be different between the teeth 12 and the arc portions 13. Furthermore, in the integrated stator cores 1A and 1B shown in Fig. 1, the volume ratio of the soft magnetic material may be different between the teeth 3 and 5 and the support portions 2 and 4.

[0109] In the above embodiments, the combination of molded coils 301-303 and stator core 1 can be appropriately interchanged and selected, provided that molded coils 301-303 can be attached (do not interfere). For example, in the above embodiments, combined stator core 1D may be used in place of combined stator core 1C. Furthermore, particularly in the case of stators 20 used in outer rotor motors, interference between molded coils 301 and 302 is often not a consideration. Therefore, for example, a separately formed integrated stator core 1B (FIG. 1B) may be assembled with coils 30 individually covered with injection-molded resin layers 312.

[0110] In the above embodiment, the molded coils 301 to 303 may be replaced with a coil 30 with an insulating coating.

[0111] Furthermore, the molded coils 301 to 303 may be covered with an injection-molded resin layer 312 in a state where the spiral structure 311 is provided with an insulating coating.

[0112] Furthermore, in the above embodiment, the coil 30 is a concentrated winding coil, but it may be a distributed winding (wave winding, lap winding, etc.) coil.

[0113] Furthermore, in the above embodiment, the stator core 1 (stator 20) is molded from a resin containing a soft magnetic material as a motor component. However, the present invention is not limited to this, and for example, a part or all of the rotor (a support portion for a magnet) may be molded from a resin containing a soft magnetic material.

[0114] <Resin Molded Body, Soft Magnetic Material> The characteristics of the stator core 1 (resin molded body) and the soft magnetic material of the first embodiment will be described with reference to FIG. 18 . FIG. 18 is a diagram showing the magnetic flux density distribution of a motor having a conventional stator ( FIG. 18(A) ) and a motor having the stator 20A of the first embodiment ( FIG. 18(B) ). The stator 20A of the first embodiment is a stator 20A consisting of a roughly T-shaped split core 11 to which the molded coil 301 shown in FIG. 4 is attached, while the conventional stator is a stator consisting of a roughly T-shaped split core made of laminated steel plates. In other words, the shapes and sizes of the stator cores are generally similar. However, the conventional stator uses a coil with an insulating coating instead of the molded coil 300.

[0115] The molding conditions for the stator 20A shown in FIG. 18(B) are as follows.

[0116] Molding temperature: 200°C to 350°C (adjusted appropriately depending on the material of the injection-molded resin layer 312 of the molded coil 300)

[0117] Mold temperature: room temperature to 150°C (adjusted appropriately depending on the material of the injection-molded resin layer 312 of the molded coil 300)

[0118] Filling pressure during injection molding: Adjust appropriately according to the shape and size of the finished product.

[0119] As is clear from Figure 18, the stator 20 (stator core 1) of the first embodiment can achieve a magnetic flux density equivalent to that of a stator core made of electromagnetic steel sheets, and it was found that good motor characteristics can be obtained. Note that, although Figure 18 shows high magnetic flux density in only some teeth, this shows the state of magnetic flux density at a certain timing, and the teeth with high magnetic flux density change over time as the motor rotates.

[0120] Furthermore, in this case, the weight of the stator 20 of the first embodiment was approximately 15% lighter than that of a stator made of electromagnetic steel sheets, and the induced voltage was able to maintain the same performance as that of a stator made of electromagnetic steel sheets.

[0121] <Soft Magnetic Material> In the first embodiment, permendur was used as the soft magnetic material. However, the soft magnetic material is not limited to this. In addition to iron-based powder (iron powder, pure iron powder), powders of silicon steel (Fe-Si alloy), sendust (Fe-Si-Al alloy), permalloy (Fe-Ni alloy), amorphous soft magnetic alloy, etc. may also be used. The soft magnetic material has a predetermined particle size (for example, approximately 500 μm or less).

[0122] The resin with which the soft magnetic material is mixed is preferably, for example, a thermoplastic resin (for example, polyamide (PA) resin such as PA12, PA6, or PA66, or polyphenylene sulfide (PPS) resin). If further heat resistance is required, heat-resistant nylon (PA6, PA66) or PPS resin can be used instead of PA12.

[0123] In the stator core 1, in terms of volume % of the resin molding, for example, the soft magnetic material is 55 volume % or more and 85 volume % or less, and the resin is 45 volume % or more and 15 volume % or less; desirably, the soft magnetic material is 65 volume % or more and 80 volume % or less, and the resin is 35 volume % or more and 25 volume % or less; preferably, the soft magnetic material is 70 volume % or more and 80 volume % or less, and the resin is 30 volume % or more and 20 volume % or less; and more preferably, the soft magnetic material is approximately 75 volume % and the resin is approximately 25 volume %.

[0124] In the above-described embodiment, the soft magnetic material may be heat-treated while it is still in its raw state (before being mixed with the resin). For example, in the case of permendur, it is particularly desirable to perform heat treatment in a hydrogen atmosphere at 700°C to 1000°C for 1 hour to 5 hours, preferably at 800°C to 900°C for 2 hours to 4 hours, and more preferably at 850°C for 3 hours. The soft magnetic material is then mixed with resin and injection-molded to form the stator core 1.

[0125] 19 is a graph showing the change in saturation magnetic flux density depending on the volume ratio of the soft magnetic material in the stator core 1 of the first embodiment. The vertical axis represents saturation magnetic flux density (T), and the horizontal axis represents the volume ratio of the soft magnetic material to the resin molded body. The target value (T) indicated by the dotted line in the graph is the saturation magnetic flux density equivalent to a stator core of approximately the same shape constructed from electromagnetic steel sheets.

[0126] In addition, the solid line shows the change in saturation magnetic flux density depending on the volume ratio of the soft magnetic material, and indicates the change when heat treatment is performed before mixing the soft magnetic material with the resin when molding the stator core 1, and the dashed line shows the change in saturation magnetic flux density depending on the volume ratio of the soft magnetic material, and indicates the change when heat treatment is not performed before mixing the soft magnetic material with the resin.

[0127] 19 shows that by performing heat treatment during molding of the stator core 1 (before mixing with resin), it is possible to approach the target saturation magnetic flux density even with the same volume ratio compared to when heat treatment is not performed. Also, when heat treatment is not performed, it is (naturally) possible to approach the target saturation magnetic flux density by increasing the volume ratio of the soft magnetic material.

[0128] 10 shows a configuration in which multiple spiral structures 311 in the molded coil 303 are connected by the wiring member W, but all of the spiral structures 311 in one molded coil 303 may be connected by the wiring member W, or at least one spiral structure 311 may not be connected to other spiral structures 311 in the same molded coil 303, but may be connected to a spiral structure 311 in another molded coil 303. Furthermore, multiple spiral structures 311 in the molded coil 303 do not have to be connected by the wiring member W.

[0129] <<Second Embodiment>> Next, a second embodiment of the present invention will be described in detail with reference to FIGS. 20 to 37. <Coil Unit> FIG. 20 is a schematic plan view (top view) illustrating a coil unit 500 (500A) according to the second embodiment. The coil unit 500 is assembled to a stator core, for example, to form a motor component (stator). FIG. 20(A) is a schematic plan view illustrating an example of the coil unit 500, viewed from a direction perpendicular to the helical axis AX1 of the coil 502 indicated by the dashed dotted line (for example, a direction along the rotation axis AX2 of the motor when the coil unit 500 is assembled to the stator). FIGS. 20(B) and 20(C) are schematic plan views showing a portion of the coil unit 500. The schematic plan view and plan view in the second embodiment are both planes viewed from a direction along the rotation axis AX2 of the motor.

[0130] Referring to FIG. 20A, a coil unit 500 (500A) of the second embodiment has a plurality of coils 502 and an injection-molded resin (which may also be referred to as an injection-molded resin layer; the same applies to the second embodiment below) 503 that integrally covers the plurality of coils 502. Each of the coils 502 has a spiral structure formed from, for example, a conductor. FIG. 20 shows, as an example, a case in which three coils 502 (conductors) are directly and integrally covered with the injection-molded resin 503. The injection-molded resin 503 is, for example, polyphenylene sulfide (PPS), liquid crystal polymer (LCP), nylon, or the like.

[0131] In the second embodiment, the coil 502 covered with the injection-molded resin 503 in this manner is called a molded coil. That is, the coil unit 500 of the second embodiment is a molded coil unit.

[0132] In the drawings of the second embodiment, for convenience of explanation, the coil 502 inside the molded coil unit 500 (500A) may be shown by a dashed line, but in reality, at least the spiral structure of the coil 502 cannot be seen from the outside of the molded coil unit 500, except for the end TS of the coil 502. All of the coils 502 are arranged in a direction such that, for example, all of the end TS can be seen on the same plane in a plan view (for example, FIG. 20(A)) (the same applies to the following embodiments).

[0133] 20(B) is a schematic plan view showing coils 502 extracted from inside the coil unit (molded coil unit) 500. The multiple coils 502 each have the same size and shape (including the number of turns), but the shape and / or size of at least one of the multiple coils 502 may be different from the shape and / or size of the other coils 502.

[0134] Each coil 502 of a molded coil unit 500 may be connected to the outside (another molded coil unit 500) or to other coils 502 in the same molded coil unit 500 by a wiring member W (such as a bus bar or a linear conductor) as appropriate, depending on the desired potential relationship. FIG. 20 conceptually illustrates this and does not limit the connection of all coils 502 in one molded coil unit 500 by a wiring member W. That is, in one molded coil unit 500, all coils 502 may be connected by a wiring member W, and three coils 502 may be continuous in the spiral progression direction, or at least one coil 502 may not be connected to other coils 502 in the same molded coil unit 500, but may be connected to a coil 502 in another molded coil unit 500. Furthermore, the three coils 502 do not have to be connected by a wiring member W.

[0135] Each wiring member W is connected to an end TS of the spiral of the coil 502 and exposed from the injection-molded resin 503, but at least a portion of the wiring member W may be covered by the injection-molded resin 503. For example, when at least one coil 502 included in the molded coil unit 500 is a wiring member W and is connected to another coil 502 included in the same molded coil unit 500 or another molded coil unit, at least a portion of the wiring member W and the end TS of the coil 502 connected to the wiring member W may be covered by or exposed from the injection-molded resin 503. Although the wiring member W is not shown in the following embodiments, the wiring member W (the connection between the coils) in the second embodiment is the same as that described above in FIG. 20.

[0136] In one molded coil unit 500, the multiple coils 502 are arranged in a partial ring shape in the plan view shown in Fig. 20. Here, "partial ring" refers to a shape (arc shape) that constitutes part of the circumference of a disk or ring, for example, a shape that constitutes part of the circumference (arc) when the planar shape of the stator (the shape when viewed from a direction along the rotation axis AX2 of the motor) is a disk or ring. In other words, the outer shape of the molded coil unit 500 is also partial ring (Fig. 20(A)).

[0137] Fig. 20(C) is a diagram showing only the injection-molded resin (injection-molded resin layer) 503 of the molded coil unit 500. Fig. 20(C) is a schematic plan view of the stator cut in the radial direction along a cutting line near the center in the height direction, when the direction along the rotation axis AX2 is the height direction of the coil 502.

[0138] Injection-molded resin 503 has through-holes 505 formed along the central portion of the spiral structure of each coil 502, more specifically along the inner periphery of the spiral structure. When coil unit (molded coil unit) 500 is attached to a stator core, parts of the stator core (teeth) are inserted into through-holes 505.

[0139] Further explanation will be given with reference to Figure 21. Figure 21(A) is an external perspective view showing one coil 502 in molded coil unit 500 (500A), and Figure 21(B) is a cross-sectional view taken along line x-x in Figure 21(A). Figure 21(C) is a cross-sectional view corresponding to line y-y in Figure 21(A) in a state (molded coil unit 500A) covered with injection-molded resin 503.

[0140] 21A, coil 502 is a helical structure formed by conductor C. Here, as an example, coil 502 is a so-called concentrated winding coil in which the regions of one revolution around helical axis AX1 (circumferential regions CR) are generally overlapped in the direction of helical axis AX1. In addition, injection-molded resin 503 is provided with through-hole 505 along central portion 504 of the helical structure around helical axis AX1 (FIG. 24C).

[0141] For example, the multiple coils 502 included in one molded coil unit 500 all have the same shape. Specifically, the coils 502 have the same overall size, shape, and number of spiral turns. Furthermore, the multiple coils 502 have the same size and shape of the winding regions CR in corresponding turns. That is, the three coils 502 have approximately the same size and shape of the winding regions CR in the first turn of each spiral structure, the same size and shape of the winding regions CR in the second turn, and the same size and shape of the winding regions CR in the nth turn. The coils 502 are entirely covered by the injection-molded resin 503, except for the ends (start end and end end) TS of the spiral. The coils 502 (conductors C) are not exposed even in the through-holes 505 in the injection-molded resin 503 (see FIG. 5A ).

[0142] 21(B) and 21(C), in each of the coils 502 of the molded coil unit 500 (500A), a predetermined gap G is secured between the winding regions CR, and injection-molded resin 503 is also provided in the gap G. That is, in the coil 502, the conductor C over the entire region except for the end portion TS is in direct contact with the injection-molded resin 503, and the multiple overlapping winding regions CR in the direction of the helical axis AX1 are insulated from each other by the injection-molded resin 503.

[0143] As shown in FIG. 21C, injection molding resin 503 is also placed in areas 506 where the plurality of coils 502 in the molded coil unit 500A are adjacent to each other.

[0144] Conventionally, for example, in the case of coils that make up a stator, which is a component of a motor, the spiral conductor has been coated with insulating resin over the entire length of the spiral (longitudinal direction) by dipping or spraying, and then attached to the teeth of the stator core via an insulating material (e.g., insulating paper or insulating resin material).

[0145] However, when applying an insulating coating to the coil 502 (copper wire) by, for example, spraying or dipping, the film thickness must be strictly controlled, and even if the film thickness is controlled, it is almost impossible to completely eliminate the occurrence of pinholes, making it difficult to simplify the manufacturing process and reduce yield.

[0146] Furthermore, the spiral structure is flexible, and when attached to the teeth, the overlapping circumferential regions in the direction of the spiral axis can shift, making it difficult to handle, or the thin insulating coating can be damaged, reducing its voltage resistance.

[0147] According to the second embodiment, each coil 502 is a molded coil, and the winding regions CR of the coils 502 are insulated from each other by injection-molded resin 503, and adjacent coils 502 in one molded coil unit 500A are also insulated from each other by injection-molded resin 503.

[0148] Therefore, an insulating coating process (a process of coating an insulating resin by dipping, spraying, or the like) for the coil 502 is not required. Also, because the winding regions CR of the coil 502 are fixed to each other by the injection-molded resin 503, it is possible to prevent misalignment and expansion / contraction between the winding regions CR that overlap in the direction of the helical axis AX1. In particular, for example, when multiple coils 502 are connected, covering them integrally with the injection-molded resin 503 can prevent the coils 502 from being misaligned or damaged.

[0149] Furthermore, it is possible to eliminate the need for the process of attaching insulating materials (insulating paper, insulating resin materials, etc.) between the coil and teeth, which was previously required for assembling a stator. This significantly improves the ease of handling when attaching to the teeth, and reduces the number of parts. It also prevents the deterioration of voltage resistance due to the conductor C being exposed.

[0150] Furthermore, since multiple (n) coils 502 are integrated (molded) using a single injection molding resin 503, handling during the assembly process can be further improved compared to when each of the n coils 502 is made into an individual molded coil.

[0151] Furthermore, compared to when n coils 502 are individually molded coils, the number of parts required for the finished product can be reduced to 1 / n. As a result, variations in the finished product after assembly and variations in working time due to the level of skill of the assembly worker can be reduced.

[0152] Furthermore, handling can be improved when the stator is assembled by an assembly device (automated assembly) instead of by a worker.

[0153] That is, handling of the coil 502 itself during the manufacturing of the stator becomes easier, which leads to more efficient (simplified) manufacturing processes, improved yields, and reduced component costs.

[0154] Furthermore, by using, for example, a thermally conductive resin as the injection-molded resin 503, it is possible to improve heat dissipation efficiency. This makes it possible, for example, to closely fit the molded coil unit 500 to the housing (case) of the motor. By directly abutting the injection-molded resin 503 against the housing, heat generated in the coil 502 is dissipated to the outside via the housing, thereby improving the heat dissipation of the coil 502 and ultimately improving the characteristics of the motor. In addition, the reduction in unnecessary space allows the housing to be made more compact, which contributes to the miniaturization of the motor.

[0155] An example of a manufacturing method for the molded coil unit 500 (500A) of the second embodiment will be described with reference to Figures 21 and 22. Figure 22 is a schematic plan view showing the manufacturing method for the molded coil unit 500A.

[0156] First, as shown in FIGS. 21A and 22A , a coil (spiral structure) 502 is formed from a conductor C (e.g., a metal conductor primarily composed of copper and / or aluminum). The coil 502 is formed, for example, by preparing a plurality of strip-shaped (e.g., U-shaped) conductors C (flat conductors (coil pieces)) and connecting the longitudinal end faces of the strips by butting and pressing them together. However, the method for manufacturing the coil 502 is not limited to this, and any method can be used. For example, the coil 502 may be formed by butting and pressing the end faces of a plurality of strip-shaped round wire conductors (conductors C having a substantially circular cross section transverse to the longitudinal direction) together. Alternatively, the coil 502 may be formed by winding a long (final length of the coil 502; the same applies below) flat conductor (without any splicing) around the conductor C, or a long round wire conductor (without any splicing) around the conductor C. Alternatively, the coil 502 may be formed by winding a long round wire conductor in a spiral shape and then pressing it in the direction of the spiral axis AX1 to form it into a flat wire conductor.

[0157] Whether the coil is formed by connecting strip-shaped conductors C or by winding a long conductor C, the distances between the winding regions CR generally vary to an arbitrary distance immediately after the completion of the coil 502, as shown in Fig. 22(A). Therefore, the distances between the winding regions CR are expanded or contracted in the direction of the helical axis AX1, so that the distances between the winding regions CR are approximately equal, as shown in Fig. 21(B). Furthermore, the alignment of the overlapping winding regions CR is adjusted so that the centers of all the winding regions CR are aligned with the helical axis AX1, and the coil 502 shown in Fig. 21(B) is completed.

[0158] In the completed coil 502 shown in Figure 21 (B), all of the winding regions CR are spaced apart by approximately the same distance P. The distance P between the winding regions CR is a length that is necessary and sufficient for the completed coil 502. The distance P can be ensured to be approximately uniform by, for example, a spacer member (not shown) that is provided integrally with the coil 502 or that is separate from the coil 502. However, the distance P may also be ensured by elastic deformation and / or plastic deformation without using a spacer member.

[0159] As shown in Figure 22(B), a plurality of coils 502 (three in this example) formed in this manner are prepared. At least one of the plurality of coils 502 may be formed by a manufacturing method different from that of the other coils 502. In either case, however, the coil 502 (spiral structure) is made of the conductor C itself, and is not coated with an insulating coating (insulating coating-less coil 502). The plurality of coils 502 are connected by wiring members W (not shown in Figure 22) as needed.

[0160] 22(C), the coils 502 are arranged in a partial ring shape in a predetermined injection molding die (mold forming die) 901 while maintaining the distance P between the winding regions CR of each coil 502. It is desirable that each coil 502 has an outer shape that is approximately a quadrangular truncated pyramid, as shown in FIG. 21(A), for example. In the example shown in FIG. 22, the coils 502 are arranged in a partial ring shape (arc shape) with the shorter side of the trapezoid facing inward in a plan view.

[0161] Although detailed illustration of the injection molding die 901 is omitted, it is a die in which through-holes 505 (FIGS. 20C and 21C) are formed at positions corresponding to the central portions 504 of each coil 502. Molten resin (e.g., PPS, LCP, nylon, etc.) is then injected and solidified. As a result, as shown in the partial perspective view of FIG. 22D and the external view of FIG. 22E, the multiple coils 502 are covered with injection molding resin 503 except for the end portions TS, forming an integrated molded coil unit 500A. The inner periphery of each coil 502 is also covered with injection molding resin 503, so that the coils 502 (conductors C) are not exposed from the through-holes 505.

[0162] It is also possible to provide a spacer in the molding die 901 to separate the winding regions CR by a predetermined distance P, without performing molding in advance to ensure the distance P between the winding regions CR of the coil 502. In this case, the formation of the coil 502 with the winding regions CR separated by the predetermined distance P and the coating and integration of the coil 502 with the injection molding resin 503 can be performed simultaneously.

[0163] In the molded coil unit 500 (500A) of the second embodiment, multiple coils 502 are entirely and integrally covered with injection-molded resin 503, except for their end portions TS. As shown in FIG. 21C , the conductors C of the coils 502 (without an insulating coating) are in direct contact with the injection-molded resin 503, and the multiple overlapping winding regions CR in the helical axis direction are insulated by the injection-molded resin 503. The winding regions CR are fixed together by the injection-molded resin 503, with a distance P maintained between them. In this way, the molded coil unit 500 does not provide an insulating coating on the conductors C, and the conductors C are insulated by the injection-molded resin 503. The distance P may be any value, but should be large enough to allow the injection-molded resin to reliably penetrate between the winding regions CR and insulate the winding regions CR from each other.

[0164] Furthermore, the molded coil unit 500A has a partially annular outer shape. In other words, by combining a plurality of these molded coil units 500A, they become a component of a ring-shaped stator as a whole. In this case, the molded coil unit 500A can also be said to be a component (motor member) that constitutes a motor.

[0165] For example, if the motor is a three-phase motor, the three coils 502 constituting the U, V, and W phases of the three-phase motor may be molded integrally (as one molded coil unit 500A). In this case, the three coils 502 constituting one molded coil unit 500A may be connected by wiring member W. Also, the three coils constituting one molded coil unit 500A do not have to be connected by wiring member W. In other words, the coil 502 constituting the U phase of one molded coil unit 500A may be connected by wiring member W to the coil 502 constituting the U phase of another molded coil unit 500A. Similarly, the coil 502 constituting the V phase of a certain molded coil unit 500A may be connected to the coil 502 constituting the V phase of another molded coil unit 500A by another wiring member W, and the coil 502 constituting the W phase of a certain molded coil unit 500A may be connected to the coil 502 constituting the W phase of another molded coil unit 500A by yet another wiring member W.

[0166] For example, by varying the phases of the current or voltage of the three coils 502 that make up one molded coil unit 500A, for example, to U-phase, V-phase, and W-phase, a stator for a three-phase motor can be obtained.

[0167] Furthermore, multiple coils 502 constituting each of the U, V, and W phases may be molded together (as a single molded coil unit 500A). In this case, the multiple coils 502 inside each molded coil unit 500A are connected by wiring members W. In this way, the wiring members W (see FIG. 20 ) between the coils 502 may be connected in any suitable manner depending on the usage state. Furthermore, the wiring members W may be connected before or after the coils are covered with the injection-molded resin 503.

[0168] For example, by varying the phases of the current or voltage of the three coil units 500A to, for example, U-phase, V-phase, and W-phase, a stator for a three-phase motor can be obtained.

[0169] Another molded coil unit 500 (500B) will be described with reference to Fig. 23. Fig. 23 is a diagram showing an example of the molded coil unit 500B, and is a schematic plan view seen from the direction of the rotation axis AX2 of the motor.

[0170] The molded coil unit 500B has a plurality of coils 502 arranged in a ring shape, which are integrally covered with injection-molded resin 503. In this case, it is also desirable that each coil 502 has an outer shape that is approximately a truncated quadrangular pyramid, as shown in Fig. 21(A). In the example shown in Fig. 23, the plurality of coils 502 are arranged in a ring shape with the shorter side of the trapezoid in a plan view facing the inner periphery (the side closer to the rotation axis AX2).

[0171] Injection-molded resin 503 shown in Fig. 23(A) is configured in a continuous ring shape. Alternatively, as shown in Fig. 23(B), injection-molded resin 503 may have a generally ring-like overall shape, but may have a cut SP in one portion (between a pair of adjacent coils 502) to form a discontinuous, generally C-shape. Even in this case, coil 502 is not exposed from injection-molded resin 503 at the cut SP portion.

[0172] 23A and 23B, the through holes 505 are not shown, but as shown in Fig. 1C, the through holes 505 are provided at positions corresponding to the central portions 504 of the coils 502. In this case as well, the coils 502 (conductors C) are not exposed from the through holes 505.

[0173] The state of the individual coils 502 of molded coil unit 500B and the injection-molded resin 503 covering them is the same as the state of the coils 502 and injection-molded resin 503 in molded coil unit 500A described with reference to Fig. 21. Furthermore, although not shown, the multiple coils 502 arranged in a ring shape are appropriately connected to other coils 502 by one or more desired wiring members W. The wiring members W connected to the ends TS of the coils 502 are provided outside the injection-molded resin 503, but at least a portion of them may be covered by the injection-molded resin 503 (the same applies to the following embodiments).

[0174] For example, when a molded coil unit 500B is attached to a stator as a motor component, multiple coils 502 arranged in a ring shape are integrally covered with injection-molded resin 503 as shown in Fig. 23 to form a single component, improving handleability. In this case, for example, a stator core formed of a divided core (described later) or a stator core that can be molded into any shape by resin molding as in the first embodiment is used.

[0175] The method for manufacturing the molded coil unit 500B shown in FIG. 23 is similar to the method for manufacturing the molded coil unit 500A shown in FIG.

[0176] That is, after forming a spiral structure using the conductor C, it is shaped so that gaps G of a distance P are generated between the winding regions CR, and the winding regions CR are aligned to form the final shape of the coil 502. In this case, too, the coil 502 is made of the conductor C itself, and is not coated with an insulating coating (insulating coating-less coil 502).

[0177] 23(C) and 23(D), the multiple coils 502 are arranged in a ring shape in a predetermined injection molding die (mold forming die) 901 while maintaining the distance P between each of the circumferential regions CR. In this case, although not shown, the injection molding die 901 is a die in which a through-hole 505 is formed near the center of each coil 502. Molten resin (e.g., PPS, LCP, nylon, etc.) is then injected and solidified. As a result, the multiple coils 502 are covered with a ring-shaped injection molding resin 503, as shown in FIG. 23(A), to form an integrated molded coil unit 500B.

[0178] Alternatively, a molding die 901 is used to inject and solidify molten resin (e.g., PPS, LCP, nylon, etc.) into the coils 502. The die 901 has a through-hole 505 formed near the center of each coil 502 and a notch SP formed in part of the annular shape. As a result, the coils 502 are covered with a substantially C-shaped (substantially annular) injection molding resin 503, forming an integrated molded coil unit 500B, as shown in FIG. 23(B).

[0179] In this case, too, spacers that separate the winding regions CR by a predetermined distance P may be provided in the molding die 901 without performing molding in advance to ensure the distance P between the winding regions CR of the coil 502. In this case, the formation of the coil 502 with the winding regions CR separated by the predetermined distance P and the coating and integration of the coil 502 with the injection molding resin 503 can be performed simultaneously.

[0180] The annular molded coil unit 500B can provide the same effects as the molded coil unit 500A shown in Fig. 20. Furthermore, compared to the partially annular molded coil unit 500A, the number of parts can be further reduced, handling can be improved, and the efficiency of the manufacturing process can be improved.

[0181] 24 to 37, a motor member 800 according to the second embodiment will be described. The motor member 800 includes the molded coil unit 500 (500A, 500B) and a core (stator core 600) to which the molded coil unit 500 is attached. In other words, the motor member 800 according to the second embodiment is a stator or a component (partial stator unit) that constitutes a stator.

[0182] Figure 24 shows an example of a stator core 600 (600A) to which the molded coil unit 500 (500A, 500B) of the second embodiment is assembled, where Figure 24(A) is a schematic plan view seen from the direction of the motor's rotation axis AX2, and Figure 24(B) is an external oblique view showing a portion of the stator core 600A.

[0183] The stator core 600A is, for example, a combined stator core 600A in which a plurality of split cores 601 are combined to form an annular core. The combined stator core 600A shown in FIG. 24 is, for example, made up of a plurality of split cores 601 that are approximately T-shaped in plan view. FIG. 24(B) is an external perspective view of one split core 601. The multiple split cores 601 all have the same shape, each having an arc portion 603 and teeth 602 that protrude radially inward from the arc portion 603. The arc portions 603 of the multiple split cores 601 are then lined up in the arc length direction and connected to form the combined stator core 600A in which a plurality of teeth 602 are arranged in an annular shape. In this case, the arc portions 603 can also be considered as connecting portions.

[0184] This combined type stator core 600A is a stator core used in an inner rotor type motor in which a rotor is disposed on the inner periphery of a stator, and has an arc portion 603 arranged in an annular shape centered on the rotation axis AX2 of the motor, with teeth 602 protruding radially inward from the arc portion 603. The multiple teeth 602 are inserted into through holes 505 of the coil 502. The combined type stator core 600A (the divided cores 601 constituting it) is made of, for example, laminated steel plates.

[0185] A motor member (stator 800 or partial stator unit 800p) can be formed by assembling stator core 600 (600A) and molded coil unit 500. This will be explained in detail below.

[0186] FIG. 25 is a schematic plan view showing the state in which the combined stator core 600A (its split cores 601) is attached to the molded coil unit 500A shown in FIG. 20 . As shown in FIG. 25A , the teeth 602 of the split cores 601 are inserted into the through holes 505 of the molded coil unit 500A, and the arc portions 603 of the split cores 601 are connected to each other. This results in a unit (partial stator unit 800p (800pa)) that can form the stator shown in FIG. 25B . Then, by combining a predetermined number of these partial stator units 800pa (four sets in this example) to form a ring shape as a whole, the stator 800 (800A) can be obtained. Both the partial stator units 800p (800pa) and the stator 800 (800A) are motor components in the second embodiment.

[0187] In addition, as a manufacturing method for the stator 800A shown in Figure 25 (B), instead of forming partial stator units 800pa and then combining a predetermined number of them, a predetermined number (four sets in this example) of molded coil units 500A can be arranged in a ring shape, and then the teeth 602 of the split core 601 can be inserted into each through hole 505 to connect the arc portions 603 to each other.

[0188] FIG. 26 is a schematic plan view showing a state in which a roughly T-shaped split core 601 is attached to an annular molded coil unit 500B.

[0189] 26A, the teeth 602 of the split core 601 are inserted into the through holes 505 of the molded coil unit 500B, and the arc portions 603 of the split core 601 are connected to each other. This makes it possible to obtain a stator (motor component) 800 (800B) in which the annular molded coil unit 500B is assembled to the combined stator core 600A.

[0190] Figure 27 is a diagram showing another example of a stator 800 (800C) and a partial stator unit 800p (800pc). Figures 27(A) and 27(B) are schematic plan views showing another example of a stator core 600 (600B), Figure 27(C) is a schematic plan view showing a partial stator unit 800p, and Figure 27(D) is a schematic plan view showing a portion of the stator 800. Note that all Figures 27 are schematic views, and the scales of Figure 27(A) and Figures 27(B) to 27(D) are different.

[0191] 27A and 27B, the stator core 600 in this example is a combined stator core 600B and is composed of approximately T-shaped split cores 611, and each split core 611 has (a plurality of) teeth 612, the same number as the number of coils 502 in the molded coil unit 500A, which are integral with one arc portion 613. Specifically, in this example, three teeth 612 are integral with one arc portion 613. When multiple split cores 611 (four sets in the example of FIG. 27A) are combined, for example, an inner rotor type combined stator core 600B is formed.

[0192] In this case, as shown in Fig. 1C, a partial stator unit 800pc is constructed by assembling one molded coil unit 500A to one split core 611. Then, although not shown in Fig. 1D by being indicated by a large dashed line, a predetermined number of partial stator units 800pc can be combined to form a ring-shaped structure to form a stator 800C.

[0193] In this case, the curvature of the arc portion 613, the length of the teeth 612, and the distance between adjacent teeth 612 are set to values ​​that prevent the assembled molded coil units 500A from interfering with each other.

[0194] Figures 28 and 29 are diagrams showing another example of a stator 800 (800D). Figure 28 is a diagram showing another example of a stator core 600 (600C), and the stator core 600 of this example is also a combined stator core 600C. Figure 28(A) is a schematic plan view showing the combined stator core 600C, and Figures 28(B) and 28(C) are diagrams showing the state in which the split cores 621 are assembled into the combined stator core 600C, and are side views of the annular combined stator core 600C in the plan view of Figure 28(A) as seen from the circumferential direction. Figure 29 is a schematic plan view showing the stator 800 (800D).

[0195] 28A , the combined stator core 600C is composed of a plurality of split cores 621 that are generally I-shaped in plan view and cylindrical (annular) support portions (connecting portions) 623. The split cores 621 and the support portions 623 are configured separately. Each split core 621 has, for example, wedge-shaped protrusions 622 at one radial end (the radially inner side) of the support portions 623, and the support portions 623 have recesses 624 on their outer peripheral surface that are equally spaced circumferentially and conform to the shape of the protrusions 622. In other words, the protrusions 622 and the recesses 624 are engageable with each other, and this engagement forms the split cores 621 into teeth 625 that protrude radially outward from the outer peripheral surface of the support portions 623. This combined stator core 600C is a stator core used in an outer rotor motor in which a rotor is disposed on the outer periphery of a stator.

[0196] 28B and 28C, the split core 621 (teeth 625) is attached to the support portion 623 by aligning the convex portion 622 of the split core 621 with the concave portion 624 of the support portion 623 above and below the central axis (rotation axis AX2 of the motor) of the substantially annular (cylindrical) support portion 623, and then inserting and fixing them along the direction of the rotation axis AX2. In this case, the convex portion 622 of the wedge-shaped split core 621 and the concave portion 624 of the support portion 623 can be inserted and slid vertically, while a clearance is set so that rattle does not occur after engagement.

[0197] The manufacturing method for the stator 800 (800D) using this combined stator core 600C is as follows: first, as shown in FIG. 29(A), a roughly I-shaped split core 621 (teeth 625) is inserted into each of the through holes 505 of the molded coil unit 500A. This state can also be called a partial stator unit. Then, as shown in FIG. 29(B), the convex portion 622 of the split core 621 is aligned with the concave portion 624 of the support portion 623, and the two are inserted and fixed. Then, by combining multiple (four sets in this case) molded coil units 500A so that the overall shape is roughly annular, the stator 800D can be obtained.

[0198] Although not shown, it is also possible to insert a roughly I-shaped split core 621 (teeth 625) into each of the through holes 505 of the annular molded coil unit 500B shown in Fig. 23, align the convex portion 622 of the split core 621 with the concave portion 624 of the support portion 623, and then insert and fix both in the direction of the rotation axis AX2. In this way, a stator 800D can be obtained in which the annular molded coil unit 500B is assembled to the combined type stator core 600C.

[0199] Another example of the stator 800 (800E) will be described with reference to FIGS. 30 and 31 . FIG. 30 is a diagram showing another example of the stator core 600 (600D). The stator core 600 in this example is also a combined stator core 600D. FIG. 30(A) is a schematic plan view showing the combined stator core 600 (600D), FIGS. 30(B) to 30(D) are diagrams showing a portion of the combined stator core 600D, FIG. 30(B) is an expanded side view in which the teeth portions 633 arranged in an annular shape in the plan view ( FIG. 30(A)) are expanded so that the circumferential direction is horizontal (the left-right direction in the drawing), FIG. 30(C) is a schematic plan view of the teeth portions 633, and FIG. 30(D) is a schematic plan view of the support portions 635. FIG. 31 is a schematic plan view showing a stator 800E using the combined type stator core 600D and another example of the stator core 600D (teeth portion 633).

[0200] As shown in FIG. 30 , the combined stator core 600D may have a configuration in which a plurality of teeth 631, each of which is substantially I-shaped in plan view, are integrally connected by annular connecting portions 632. In this example, as shown in FIG. 30(B), the connecting portions 632 are provided such that an upper connecting portion 632u on the upper side and a lower connecting portion 632d on the lower side face each other in the direction of the rotation axis AX2 of the motor. All of the teeth 631 are arranged in an annular shape at approximately equal intervals, and on the inner periphery (the radially inner side of the combined stator core 600D), their upper ends in the direction of the rotation axis AX2 are joined to the upper connecting portion 632u and their lower ends are joined to the lower connecting portion 632d. In this way, the plurality of teeth 631 are integrally supported by the connecting portions 632 to form a teeth portion 633. Alternatively, the upper connecting portion 632u and the lower connecting portion 632d can be said to be bridged by the teeth 631. The upper connecting portion 632u and the lower connecting portion 632d are continuous in the circumferential direction, with a space between adjacent teeth 631 ( FIG. 30(B) ). At least one tooth 631A (in this example, four teeth 631A positioned at 90 degrees from each other) of the multiple teeth 631 is longer than the other teeth 631 in the radial direction of the combined stator core 600D, and further has a protrusion 634 at its tip (the end portion radially away from the rotation axis AX2). Note that the connecting portion 632 desirably has a strength sufficient to maintain (support) the multiple teeth 631 at a predetermined position (spacing), and is made of, for example, a thin metal (steel plate).

[0201] As shown in Figure 30(D), the support portion 635 is cylindrical and has recesses 636 formed on its inner periphery to engage with the protrusions 634 of the teeth 631A. The teeth 633 are arranged inside the support portion 635 and, for example, inserted in the direction of the rotation axis AX2 to engage the protrusions 634 and the recesses 636, thereby forming the coupled stator core 600D. In this case, the teeth 631 other than the tooth 631A do not abut the support portion 635, and the protrusions 634 of certain teeth 631A (four in this example), which are fewer than the total number of teeth 631, 631A (12 in this example), are engaged with the recesses 636 to fix the teeth 633 to the support portion 635. This improves work efficiency compared to when all of the teeth 631, 631A are fixed to the support portion 635.

[0202] However, all of the teeth 631 may be configured to abut against the inner periphery of the support portion 635. Alternatively, the teeth 631 may also be provided with protrusions 634, and the support portion 635 may be provided with recesses 636 corresponding to the protrusions 634, so that all of the teeth 631, 631A engage with the support portion 635.

[0203] As shown in FIG. 31A, a stator 800E can be formed by assembling a molded coil unit 500A to the teeth 631 and combining a plurality of molded coil units 500A to form a generally annular shape as a whole.

[0204] As shown in FIG. 31B , the teeth 633 may not be continuous and annular, but may be configured in a generally C-shape with the connecting portion 632 cut in the circumferential direction to have connecting portion end portions T1 and T2. In this case, the connecting portion 632 is configured from a material that is strong enough to support (maintain) the multiple teeth 631 at a predetermined position (spacing) and that is capable of deformation (flexible deformation). For example, the connecting portion end portions T1 and T2 may be spaced apart, and the molded coil unit 500A may be assembled in the expanded state. Then, as shown in FIG. 31B , the connecting portion end portions T1 and T2 may be deformed (flexed) into an annular shape so that the connecting portion end portions T1 and T2 are close to each other, and the stator 800E may be formed by fixing the connecting portion 632 to the support portion 635. Even if the teeth 633 are generally C-shaped, the multiple teeth 631 can be maintained in an annular arrangement by engaging the annular support portion 635, allowing the multiple molded coil units 500A to be arranged in an approximately annular shape.

[0205] 31(B), when teeth portion 633 is configured to be approximately C-shaped, it can be combined with an annular molded coil unit 500B (not shown). In particular, when connecting portion 632 is made of a material (such as a thin steel plate) strong enough to allow for flexural deformation, teeth 631 of teeth portion 633 can be inserted through a plurality of through holes 505 of annular molded coil unit 500B and then fixed to support portion 635, thereby forming stator 800.

[0206] The combined stator core 600D shown in Figures 30 and 31 is a stator core used in an outer rotor motor, but may also be a stator core used in an inner rotor motor in which teeth 631 protrude radially inward from the connecting portion 632. Specifically, the connecting portion 632 shown in Figure 30 is configured such that, when the rotation axis AX2 of the motor is taken as the center, the teeth 631 protrude radially outward from the center in a plan view, i.e., toward the outer periphery of the annular connecting portion 632. In contrast, although not shown, the teeth 631 may also protrude radially inward from the center in a plan view, i.e., toward the inner periphery of the annular connecting portion 632, when the axis AX2 of the stator is taken as the center. In this case, the support portion 635 is disposed on the inner periphery of the tooth portion 633, and recesses 636 provided on the outer periphery of the support portion 635 are configured to engage with the protrusions 634 of the teeth 631.

[0207] In combined type stator core 600D, convex portions 634 of teeth 631A may be concave portions, and concave portions 636 of support portions 635 may be protrusions.

[0208] Another example of the stator 800 (800F) will be described with reference to Fig. 32. Fig. 32(A) is a schematic plan view showing another stator core 600 (600E), and Fig. 32(B) is a schematic plan view illustrating the stator 800F.

[0209] 32A, this stator core 600E is an integrated stator core configured as a single component, in which multiple teeth 641 arranged in an annular shape in a plan view are integrally (inseparably) supported by a cylindrical (disk)-shaped support portion 642. The integrated stator core 600E in this example is a stator core used in an outer rotor motor. The multiple teeth 641 are arranged at approximately equal intervals around the circumferential direction of the approximately disk-shaped support portion 642 in a plan view, and protrude radially outward from the support portion 642.

[0210] 32(B), the stator 800F can be formed by assembling a predetermined number of molded coil units 500A to the teeth 641 and combining them to form a generally annular shape as a whole. In this case, the length of the teeth 641 and the distance between adjacent teeth 641 are set to values ​​that prevent the assembled molded coil units 500A from interfering with each other.

[0211] Although not shown, the integrated stator core 600E may be a stator core used in an inner rotor motor, provided that the multiple molded coil units 500A arranged in an annular pattern do not interfere with each other (see FIG. 35(C)). In this case, the multiple teeth 641 are arranged at equal intervals around the circumference of a support portion 642 that is substantially disk-shaped in plan view, and protrude radially inward from the support portion 642.

[0212] 33 is a flowchart showing one example (first method) of a method for manufacturing motor member (stator) 800 using the above-described molded coil unit 500. That is, the method for manufacturing motor member 800 includes a step of preparing a plurality of coils 502 (step S101), a step of forming molded coil unit 500 (step S103), and a step of assembling molded coil unit 500 and stator core 600 (step S105).

[0213] In step S101, a spiral structure is formed using conductor C, distance P between winding regions CR is ensured, and molding is performed to adjust the alignment of the winding regions CR, thereby forming multiple coils 502. In step S103, molded coil units 500 (500A, 500B) are formed by integrally covering the multiple coils 502 with injection-molded resin 503. In step S105, teeth (teeth 602, 612, 625, 631, 641) of stator core 600 are inserted into through holes 505 of one or more molded coil units 500, thereby forming stator (motor component) 800 in which coils 502 covered with injection-molded resin 503 are arranged in a ring shape. All of the above-mentioned stator cores 600 are made of, for example, metal (electromagnetic steel sheet).

[0214] FIG. 34 is a flowchart showing another example (second method) of a method for manufacturing a motor member (stator) using the molded coil unit 500.

[0215] The stator core 600 is not limited to being made of metal (electromagnetic steel plate), and may be molded from an injection-molded resin separate from the molded coil unit 500 .

[0216] In this case, the stator core 600 (600F) is a resin molded body molded from a resin containing a soft magnetic material. Specifically, the stator core (resin molded body) 600F is obtained by melting resin pellets kneaded with a soft magnetic material with heat, injecting the melted resin pellets into a mold of the desired shape, and then cooling and solidifying the melted resin. The soft magnetic material is present in a larger amount than the resin (pellets) in terms of volume ratio (content ratio). The soft magnetic material is, for example, permendur.

[0217] 34, the manufacturing method of a motor member (stator) by the second method includes a step of preparing coil 502 (step S201), a step of forming molded coil unit 500 (500A, 500B) (step S203), a step of setting molded coil unit 500 in core molding die 902 (step S205), and a step of molding stator core 600F from resin (step S207). That is, stator core 600F is molded after molded coil unit 500, which is arranged in a substantially annular shape to constitute stator 800.

[0218] The method for manufacturing the stator 800G by the second method will be specifically described with reference to Fig. 35. Fig. 35 is a schematic plan view illustrating a method for manufacturing the stator 800G using the molded coil unit 500B.

[0219] First, multiple coils 502 are prepared (step S201 in FIG. 34 ) and arranged in a ring shape within a mold forming die 901 with the winding regions CR spaced a predetermined distance P apart. Alternatively, multiple coils 502 are arranged in a ring shape within the mold forming die 901, and the distance P between each winding region CR is maintained and secured within the mold forming die 901. Then, pellets of resin (e.g., PPS, LCP, nylon, etc.) are melted with heat, injected into the mold forming die 901, and cooled and solidified. As a result, as shown in FIG. 35(A), an annular molded coil unit 500B is formed in which the multiple coils 502 are integrally covered with injection-molded resin 503 except for the end portions TS (step S203 in FIG. 34 ).

[0220] Thereafter, as shown in FIG. 35(B), the molded coil unit 500B is placed in another injection molding die (core molding die 902) (step S205 in FIG. 34). This core molding die 902 is a die capable of molding, for example, the inner rotor type integrated stator core 600F shown in FIG. 35(C). This integrated stator core 600F is configured as a single component, with multiple annularly arranged teeth 651 integrally (inseparably) supported by a cylindrical (disk)-shaped support portion 652. The multiple teeth 651 are arranged at approximately equal intervals in the circumferential direction of the approximately disk-shaped support portion 652 in a plan view, and protrude radially inward from the support portion 652.

[0221] Resin pellets kneaded with a soft magnetic material are melted by heat, injected into core molding die 902, and cooled to solidify. As a result, stator core 600F is molded from injection molding resin 523 as shown in Figures 35(C) and 35(D) (step S207 in Figure 34). In this case, stator core 600F is molded, and stator 800G is formed in which stator core 600F and molded coil unit 500B are integrated together.

[0222] In this case, the injection molding temperature (melting temperature of the resin pellets) in the core molding die 902 is set to a temperature (for example, 350 to 450° C.) at which the injection molding resin 503 of the molded coil unit 500B does not re-melt.

[0223] Thus, the stator core 600F made of injection molded resin 523 can be molded into any shape depending on the mold, even if the shape is complex.

[0224] In particular, the molded coil unit 500 of the second embodiment is covered with injection-molded resin 503, which eliminates variation in the shape of the coil unit (limiting flexibility and freedom of deformation) and improves handling when attached to the stator core 600. On the other hand, deformation of the coil 502 is not permitted, which may make it difficult to assemble the stator core 600, which has already been completed to a predetermined shape. However, by injection-molding the stator core 600 to match the molded coil unit 500 (500B), the stator core 600 can be molded into a desired shape. In this case, work efficiency can be improved compared to a configuration in which, for example, the molded coil unit 500A is attached to a split core 601 made of electromagnetic steel or the like and then the split core 601 is joined.

[0225] Furthermore, since the resin molded body contains resin in part, it is possible to reduce the weight compared to conventional stator cores that are made entirely of metal members such as electromagnetic steel sheets.

[0226] Furthermore, molded coil unit 500 and stator core 600F can be integrated together when stator core 600F is molded. In other words, the process of assembling molded coil unit 500 to each of teeth 651 is no longer necessary, which improves the efficiency of the process of manufacturing stator 800G.

[0227] Furthermore, even when multiple resin-molded stator cores 600F are formed in the same shape, they can be mass-produced more easily and shape variations can be reduced compared to when stator cores are formed by laminating electromagnetic steel sheets.

[0228] Figure 36 shows an example in which an annular molded coil unit 500B is assembled to an outer rotor type resin-molded stator core 600G. The shape of the stator core 600G is similar to that of the stator core 600E shown in Figure 32, which is made of, for example, electromagnetic steel sheets, but is subsequently formed by injection molding to fit the molded coil unit 500B. Although the annular molded coil unit 500B cannot be attached to the completed stator core 600G shown in Figure 36, it is subsequently formed by injecting injection molding resin 523 into a core molding die 902 in which the molded coil unit 500B is placed. Therefore, even an outer rotor type stator core 600G can be assembled to the annular molded coil unit 500B. Furthermore, the molded coil unit 500B and the stator core 600G can be integrally fixed together by resin injection molding.

[0229] This allows the manufacturing process of the motor component (stator 800) to be greatly simplified, and also reduces product variations.

[0230] The stator core 600 formed by the injection molding resin 523 may be a combined type stator core having the shape shown in, for example, FIGS. 24, 27, 28, and 30 in the second embodiment.

[0231] Alternatively, a plurality of partially annular molded coil units 500A shown in FIG. 20 may be used to form a substantially annular shape, and stator core 600 may be molded from injection molding resin 523.

[0232] Alternatively, stator core 600 in the first method shown in Fig. 33 may be molded using another injection molding resin 523 and core molding die 902. That is, as shown in Fig. 37, coil 502 is prepared (step S301), and molded coil unit 500 is formed (step S303). Separately, another injection molding resin 523 is injected into core molding die 902 and solidified to form resin stator core 600 (step S305), and after forming stator core 600, this may be assembled with molded coil unit 500 (step S307).

[0233] Furthermore, the stator core 600 formed from the injection molded resin 523 is not limited to the shape described in the second embodiment, and can be molded into any shape.

[0234] As described above, in the second embodiment, a configuration has been illustrated in which the spiral-structured conductor C constituting the coil 502 is in direct contact with the injection-molded resin 503. However, this is not a limitation, and in all of the above-described embodiments, the spiral-structured conductor C constituting the coil 502 may be coated with an insulating resin other than the injection-molded resin 503 over the entire length of the spiral (longitudinal direction), and the insulating resin (coating) may be covered with the injection-molded resin 503 in this state so that the insulating resin (coating) comes into contact with the injection-molded resin 503. When the coil 502 is coated by immersing it in insulating resin or spraying it with insulating resin, there is a risk of pinholes forming in the coating, which limits the improvement in yield. However, by further covering the coated conductor with the injection-molded resin 503, pinholes do not pose a problem and subsequent damage to the coating can be prevented.

[0235] Although the example has been given in which the number of coils 502 constituting one molded coil unit 500A is three, the number is not limited to this, and may be two or four or more.

[0236] Furthermore, the ends TS of the coil 502 do not have to be oriented so that they are all visible on the same plane in a plan view (for example, FIG. 20A).

[0237] The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit and technical concept of the present invention.

[0238] DESCRIPTION OF SYMBOLS 1 Stator core 1A, 1B Integrated stator core 1C, 1D Combined stator core 2, 4 Support portion 3, 5, 12, 18 Teeth 11, 14, 19 Split core 12 Teeth 13 Arc portion (connecting portion) 15 Convex portion 16 Support portion (connecting portion) 17 Concave portion 18 Teeth 20 (20A to 20J) Stator 21, 22, 23 Coil unit 30 Coil 201 Mold forming die 202 Core forming die 204 Single core forming die 301 to 303 Molded coil 311 Spiral structure 312 Injection molded resin (injection molded resin layer) 500 Coil unit (molded coil unit) 502 Coil 503 Injection molded resin (injection molded resin layer) 505 Through hole 523 Injection molded resin 600 Stator core 601, 611, 621 Split core 602, 612, 625, 631, 641, 651 Teeth 603, 613 Circular arc portion 622 Convex portion 623 Support portion (connecting portion) 624 Concave portion 632 Connecting portion 633 Teeth portion 634 Convex portion 635 Support portion 636 Concave portion 642 Support portion 652 Support portion 800 Motor member (stator) 800p Partial stator unit 901 Injection molding die (mold forming die) 902 Injection molding die (core forming die)

Claims

1. A motor component made of a resin molded body containing soft magnetic material.

2. A motor component comprising: a core molded from a resin containing a soft magnetic material; and a coil provided on the core.

3. The motor member according to claim 2, characterized in that the coil has an injection-molded resin layer made of another resin.

4. The motor member according to claim 3, wherein the coil has a helical structure made of a conductor, the helical structure being directly covered by the injection-molded resin layer.

5. A method for manufacturing a motor component, comprising: a step of placing a coil in a mold; and a step of injecting resin containing a soft magnetic material into the mold to form a core.

6. The method for manufacturing a motor component according to claim 5, further comprising a step of covering the coil with an injection-molded resin layer made of another resin before placing the coil in the mold.

7. A method for manufacturing a motor component, comprising: a step of molding a core from resin containing a soft magnetic material; and a step of assembling the teeth of the core and a coil.

8. The method for manufacturing a motor component according to claim 7, further comprising a step of covering the coil with an injection-molded resin layer made of another resin.

9. The method for manufacturing a motor component according to claim 6 or 8, characterized in that the resin containing the soft magnetic material is molded at a temperature at which the other resin does not melt.

10. The method for manufacturing a motor component according to claim 6 or 8, characterized in that the conductor of the coil is directly covered with an injection-molded resin layer made of the other resin.

11. The motor member according to claim 1, characterized in that the volume ratio of the soft magnetic material to the resin constituting the resin molding is higher than that of the soft magnetic material.

12. The motor member according to claim 2, characterized in that the volume ratio of the soft magnetic material to the resin is higher than that of the soft magnetic material.

13. The method for manufacturing a motor component according to claim 5 or 7, characterized in that the volume ratio of the soft magnetic material to the resin is higher than that of the soft magnetic material.

14. The motor member according to claim 1, characterized in that the volume ratio of the soft magnetic material to the resin constituting the resin molded body is made different between an area where the magnetic flux density is relatively high and an area where the magnetic flux density is relatively low.

15. A motor component as described in claim 2, characterized in that the core includes teeth to which the coil can be attached and support portions for the teeth, and the teeth and support portions have different volume ratios of the soft magnetic material to the resin.

16. The motor member according to claim 15, wherein the teeth have a larger volume ratio of the soft magnetic material than the support portion.

17. A method for manufacturing a motor component, comprising: a step of molding a plurality of teeth using a resin containing a first soft magnetic material; a step of molding a support portion capable of integrally supporting the plurality of teeth using a resin containing a second soft magnetic material; and a step of assembling the plurality of teeth and the support portion.

18. The method for manufacturing a motor component according to claim 17, further comprising a step of attaching coils to each of the plurality of teeth.

19. A method for manufacturing a motor component as described in claim 18, comprising the steps of: placing the coil in a mold; and injecting a resin containing the first soft magnetic material into the mold to integrally mold the teeth and the coil.

20. The method for manufacturing a motor component according to claim 17, characterized in that the first resin containing soft magnetic material has a higher content of soft magnetic material than the second resin containing soft magnetic material.

21. A method for manufacturing a motor component, comprising the steps of injecting resin containing a soft magnetic material into a mold and solidifying it.

22. A coil unit comprising: a plurality of coils; and an injection molded resin integrally covering the plurality of coils.

23. The coil unit according to claim 22, wherein each of the plurality of coils is a spiral structure made of a conductor, and the conductor is directly covered with the injection molding resin.

24. The coil unit according to claim 22, wherein the injection molding resin is disposed between adjacent coils among the plurality of coils.

25. The coil unit according to claim 22, wherein the injection-molded resin has a partially annular outer shape.

26. The coil unit according to claim 22, wherein the injection-molded resin has an outer shape that is annular.

27. A motor member comprising: a coil unit according to any one of claims 22 to 26; and a core to which the coil unit is attached.

28. The motor member according to claim 27, characterized in that the core is made of another injection-molded resin.

29. A method for manufacturing a coil unit, comprising: a step of arranging a plurality of coils in a mold; and a step of injecting injection molding resin into the mold to integrally cover the plurality of coils.

30. The method for manufacturing a coil unit according to claim 29, characterized in that the plurality of coils are arranged in a partial annular shape, and the entirety of the plurality of coils are covered with the injection molding resin.

31. The method for manufacturing a coil unit according to claim 29, characterized in that the plurality of coils are arranged in a ring shape and the entirety of the plurality of coils are covered with the injection molding resin.

32. A method for manufacturing a motor component, comprising the steps of: arranging a plurality of coils in a mold; injecting injection molding resin into the mold to integrally cover the plurality of coils to form a coil unit; and assembling the coil unit and a core.

33. The method for manufacturing a motor component according to claim 32, further comprising a step of molding the core from another injection molding resin.

34. The method for manufacturing a motor member according to claim 33, characterized in that after the core is molded, it is assembled to the coil unit.

35. The method for manufacturing a motor component according to claim 33, further comprising the steps of: placing the coil unit in another mold; and injecting the other injection molding resin into the other mold to mold the core.

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