Coil, stator and motor equipped with same

Abstract

A coil comprising: a wire-strand winding having wire strands, which comprise a conductor having a quadrilateral cross-section, wound and stacked n turns (n being a natural number); and an insulating resin covering the surface of the wire-strand winding. An ith turn (i being an integer, 1 ≤ i ≤ n) creates a square ring having four sides. The insulating resin covers the surface of each of the four sides, in the ith turn. During the first to nth turns, the insulating resin is continuously and integrally formed.

Description

[Technical Field]

[0001] The present disclosure relates to a coil, a stator including the coil, and a motor. [Background technology]

[0002] In recent years, demand for motors has been increasing in industrial and automotive applications, and there is a demand for improved motor efficiency and lower costs.

[0003] One method for improving motor efficiency is to increase the space factor of the coils placed inside the stator slots. By increasing the space factor of the coils, it is possible to reduce losses caused by the current flowing through the coils when the motor is running.

[0004] As a method for improving the space factor of the coil, a configuration has been proposed in which a cast coil made of copper is disposed in the slot (see, for example, Patent Document 1).

[0005] In the structure disclosed in Patent Document 1, a coil is completed by forming a compact by helically winding wires by casting, and then forming an insulating coating on the surface of the compact. At this time, the insulating coating is formed by electrodeposition coating. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] German Patent Application Publication No. 102012212637 Summary of the Invention

[0007] However, electrodeposition coating generally has a slow rate of forming an insulating coating, and the manufacturing equipment is expensive. Therefore, coils with insulating coatings formed by electrodeposition coating have the problem of increased coil manufacturing costs. Furthermore, insulating coatings formed by electrodeposition coating have large film thickness variations. Therefore, in order to ensure a predetermined dielectric strength voltage, it has been necessary to set a large target film thickness for the insulating coating. However, this has been a factor that further increases coil manufacturing costs.

[0008] The present disclosure has been made in view of the above points, and an object of the present disclosure is to provide a coil that can reduce the manufacturing cost of an insulating coating, and a stator and a motor that include the same.

[0009] In order to achieve the above object, the coil according to the present disclosure comprises a wire winding body in which a wire made of a conductor having a rectangular cross section is wound and laminated for n turns (n ​​is a natural number), and insulating resin covering the surface of the wire winding body, wherein the insulating resin covers the surface of the ith turn (i is an integer, 1≦i≦n) of the annular shape, and the insulating resin is formed continuously and integrally in the first to nth turns.

[0010] Furthermore, it is preferable that at least the jth turn (j is an integer, 2≦j≦n−1) has one or more grooves extending from the outer peripheral surface of the wire winding body to the inner peripheral surface, and that the insulating resin is formed so as to fill the grooves.

[0011] Furthermore, it is preferable that the i-th turn is a quadrangular ring having four sides, the insulating resin covers the surfaces of each of the four sides in the i-th turn, and one or more grooves are provided on each of the four sides included in at least the j-th turn.

[0012] Preferably, the groove has a tapered shape in which at least one of the width and the depth changes from the outer peripheral surface to the inner peripheral surface of the wire winding body.

[0013] Furthermore, it is preferable that a plurality of grooves are provided in at least the jth turn (j is an integer, 2≦j≦n−1), both ends of the grooves are provided on the outer peripheral surface of the jth turn, and the insulating resin is formed so as to fill the grooves.

[0014] Furthermore, the i-th turn may be a quadrangular ring having four sides, and the insulating resin may cover the surfaces of each of the four sides of the i-th turn. At least one or two pairs of the four sides included in the j-th turn that are opposed to each other may each have one or more grooves extending from one end of the side to the other.

[0015] Preferably, the groove has a tapered shape in which at least one of the width and the depth changes from one end of the side to the other end of the side.

[0016] Furthermore, at least one of the outer peripheral surface and the inner peripheral surface of the wire winding body may further have another groove portion extending along the stacking direction of the wire, and the another groove portion may be formed so as to be connected to one end of the groove portion.

[0017] Furthermore, it is preferable that the i-th turn is a quadrangular ring having four sides, the insulating resin covers the surfaces of each of the four sides of the i-th turn, at least four corners of the outer surface of each of two turns adjacent to each other in the stacking direction of the wire are provided with a recess that is recessed from the outer surface of the wire winding toward the inner surface, and the thickness of the insulating resin provided between the two turns is equal to or less than the width of the recess along the stacking direction.

[0018] Furthermore, the i-th turn (i is an integer, 1≦i≦n) may be a square ring having four sides, and in the i-th turn, the insulating resin may cover the surfaces of each of the four sides, and in two turns adjacent to each other in the stacking direction of the wire, at least one of the upper and lower sides of the outer surface of the side may be chamfered from one end of the side to the other end.

[0019] The stator according to the present disclosure comprises a stator core having teeth, a wire winding body in which a wire made of a conductor having a rectangular cross section is wound and stacked for n turns (n ​​is a natural number), and an insulating resin covering the surface of the wire winding body, wherein the insulating resin is formed so as to continuously cover at least the outer and inner surfaces of the wire winding body and both end faces in the stacking direction of the wire, and an insulating material is provided between adjacent turns.

[0020] The stator may also include a stator core having teeth and the coil described above, and the insulating resin may be formed to continuously cover the outer and inner surfaces of the wire winding body and both end faces in the stacking direction of the wire.

[0021] The insulating material provided between adjacent turns may include a material different from the insulating resin.

[0022] The insulating material may be insulating paper.

[0023] Preferably, the insulating material is provided in a plurality of spaces between adjacent turns.

[0024] The insulating resin provided on the inner peripheral surface of the coil may be in contact with the surface of the tooth portion, and the coil may be fixed to the tooth portion.

[0025] Furthermore, it is preferable that the insulating resin provided on the inner surface of the coil is formed to be thicker than the insulating resin provided on the outer surface of the coil or the insulating resin provided on either of the end faces in the stacking direction of the wire.

[0026] The motor according to the present disclosure includes at least a rotor having an output shaft at its axis, and the stator arranged coaxially with the rotor and spaced a predetermined distance from the rotor.

[0027] The coil of the present disclosure can significantly reduce the manufacturing cost of the coil, particularly the cost of forming an insulating coating on the surface of the wire winding. The stator of the present disclosure can reduce the manufacturing cost of the stator. The motor of the present disclosure can reduce the manufacturing cost of the motor. [Brief explanation of the drawings]

[0028] [Figure 1] FIG. 1 is a schematic diagram of a motor according to the first embodiment. [Figure 2] FIG. 2 is a perspective view of the coil. [Figure 3] FIG. 3 is a perspective view of a wire winding body. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. [Figure 5] FIG. 5 is an explanatory diagram of the insulating coating process. [Figure 6A] FIG. 6A is a schematic diagram of the tooth and the wire winding body set in the mold as viewed from the axial direction. [Figure 6B] FIG. 6B is a schematic diagram of the tooth and the wire winding body set in the die as viewed from the radially inner side. [Figure 7] FIG. 7 is a schematic cross-sectional view of a main part of the stator. [Figure 8] FIG. 8 is a perspective view of a coil for comparison. [Figure 9] FIG. 9 is a perspective view of a first wire winding body according to the first modification. [Figure 10] FIG. 10 is a perspective view of a second wire winding body according to the first modification. [Figure 11] FIG. 11 is a perspective view of a third wire winding body according to the first modification. [Figure 12] FIG. 12 is a perspective view of a fourth wire winding body according to the first modification. [Figure 13A] FIG. 13A is a top view of a side portion of a wire winding body according to Modification 2. FIG. [Figure 13B] FIG. 13B is a top view of a side portion of another wire winding body according to Modification 2. FIG. [Figure 14A]FIG. 14A is a schematic cross-sectional view of a side portion of a wire winding body according to Modification 3. FIG. [Figure 14B] FIG. 14B is a cross-sectional schematic diagram of a side portion of another wire winding body according to Modification 3. As shown in FIG. [Figure 15] FIG. 15 is a perspective view of a wire winding body according to the fourth modification. [Figure 16] FIG. 16 is a partially enlarged view of another wire winding body according to the fourth modification. [Figure 17] FIG. 17 is a side view of a wire winding body according to the second embodiment. [Figure 18] FIG. 18 is a partial cross-sectional view of the coil according to the second embodiment. [Figure 19] FIG. 19 is a side view of another wire winding body according to the second embodiment. [Figure 20A] FIG. 20A is a side view of yet another wire winding body according to the second embodiment. [Figure 20B] FIG. 20B is a cross-sectional view taken along line XXB-XXB in FIG. 20A. DETAILED DESCRIPTION OF THE INVENTION

[0029] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The following description of the preferred embodiments is merely exemplary in nature and is not intended to limit the present disclosure, its applications, or its uses.

[0030] (Embodiment 1) [Motor configuration] FIG. 1 is a schematic diagram of a motor 1000 according to a first embodiment. In the following description, the radial direction of the motor 1000 may be referred to as the "radial direction," the outer circumferential direction as the "circumferential direction," and the axial direction of the output shaft 210 of the motor 1000 (the direction perpendicular to the paper surface in FIG. 1) as the "axial direction." In the radial direction, the axial center side of the motor 1000 may be referred to as the inner side, and the outer circumferential side as the outer side. When viewed from the axial direction, the axial center of the motor 1000 coincides with the axis of the output shaft 210.

[0031] The motor 1000 has a stator 100 and a rotor 200. The motor 1000 has other components, such as a motor case and a bearing that supports the output shaft 210, but for the sake of convenience, these components are not shown or described here.

[0032] The stator 100 has an annular yoke 20 and a plurality of teeth (tooth portions) 10 connected to the inner periphery of the yoke 20 and arranged at equal intervals along the inner periphery. The yoke 20 connected to the teeth 10 is sometimes called a stator core 110.

[0033] The stator 100 further has slots 30 provided between the teeth 10 adjacent to each other in the circumferential direction, and coils 40 housed in the slots 30. The stator 100 is disposed radially outside the rotor 200 at a fixed distance from the rotor 200.

[0034] The teeth 10 and the yoke 20 are each formed by punching and then laminating electromagnetic steel sheets containing silicon, for example. The coils 40 are attached to each of the multiple teeth 10 and housed in the slots 30. The shape of the coils 40 will be described in detail later.

[0035] In this embodiment, the coils 40 may be referred to as coils U1 to U4, coils V1 to V4, and coils W1 to W4, respectively, depending on the phase of the current flowing through the coils 40.

[0036] The rotor 200 has an output shaft 210, a rotor core 220 having the output shaft 210 at its axis, and a plurality of magnets 230 embedded inside the rotor core 220 and arranged with north and south poles alternately along the outer circumferential direction of the output shaft 210 facing the stator 100. The material, shape, and quality of the magnets 230 can be changed as appropriate depending on the output of the motor 1000, etc. The rotor core 220 is formed, for example, by punching out electromagnetic steel sheets containing silicon or the like and then laminating them.

[0037] Coils U1 to U4 are connected in series, coils V1 to V4 are connected in series, and coils W1 to W4 are connected in series. Three-phase currents of U, V, and W phases, which have a phase difference of 120° electrical angle from each other, are supplied to coils U1 to U4, V1 to V4, and W1 to W4, respectively, to excite them, generating a rotating magnetic field in stator 100. An interaction occurs between this rotating magnetic field and a magnetic field generated by magnet 230 provided in rotor 200, generating torque, and output shaft 210 rotates while being supported by bearings (not shown).

[0038] The present disclosure can achieve the same advantageous effects even when the stator 100 is configured such that the coils U1 to U4 are connected in parallel, the coils V1 to V4 are connected in parallel, and the coils W1 to W4 are connected in parallel, or when other connection configurations are used.

[0039] [Coil configuration] Fig. 2 is a perspective view of the coil. Fig. 3 is a perspective view of the wire winding body. Fig. 4 is a cross-sectional view taken along line IV-IV in Fig. 2. In the coil 40 and the wire winding body 50, the side on which the lead portion 52 is provided in the axial direction may be referred to as the top or upper side, and the opposite side may be referred to as the bottom or lower side.

[0040] As shown in Fig. 2, the coil 40 includes a wire winding body 50 in which a wire made of a conductor having a rectangular cross section is wound spirally and laminated for multiple turns, and an insulating resin 60 that covers the surface of the wire winding body 50. For ease of explanation, the number of turns in the wire winding body 50 is set to three, but this is not particularly limited and the number may be n turns (n ​​is a natural number). The cross section of the coil 40 may be substantially rectangular. Specifically, even if the corners of the cross section of the coil 40 have a shape with chamfered corners, the same effects as those of the present disclosure can be achieved.

[0041] The wire winding body 50 includes not only a winding body in which a wire having a constant width and thickness is wound spirally, but also a "formed body."

[0042] The term "molded body" in this specification includes, for example, those formed through the following process. For example, a plurality of rectangular or L-shaped metal plates of different lengths, widths, or thicknesses are prepared, and these plates are pressed or joined by cold welding, welding, or other methods to form a molded body. The material of the plates is a low-resistivity material such as copper or aluminum.

[0043] Alternatively, the molded body may be formed by so-called casting, in which copper or the like is melted and poured into a mold. Furthermore, the molded body may be formed by bending a plate-shaped wire whose width or thickness has been varied along the way at a predetermined position. Alternatively, the molded body may be formed by rolling a plate-shaped wire whose width and thickness are constant at a predetermined position, changing the width or thickness along the way, and then winding the wire spirally. In short, the molded body is formed by adding another process to winding the wire, or by a method other than simple winding.

[0044] 3, each turn of the wire winding body 50 is a square ring having four sides 51. Both ends of the wire winding body 50 are lead portions 52 that are not covered with insulating resin 60. The lead portions 52 are connected to a bus bar or wiring (not shown) and are electrically connected to other coils 40 or an external power source (not shown).

[0045] Groove portions 53a and 53b are formed in the center of each of the four side portions 51. Groove portion 53a is formed on the outer peripheral surface of side portion 51 in the radial direction, and groove portion 53b is formed on the inner peripheral surface of side portion 51 in the radial direction. In adjacent turns, groove portion 53a and groove portion 53b are arranged opposite each other to form one groove portion 53. In other words, groove portions 53a and 53b are formed in each of the four side portions 51 included in the ith turn (i is an integer, 1≦i≦n), extending from the outer peripheral surface to the inner peripheral surface of wire winding body 50.

[0046] As shown in Fig. 4, the insulating resin 60 is continuously and integrally formed so as to cover the entire surface of the wire winding 50, including the spaces between each turn and the inside of the grooves 53. In other words, the insulating resin 60 formed on the surface of each of the first to n-th turns of the wire winding 50 is integrated. As will be described later, the wire winding 50 is set in a mold 300 (see Fig. 5) and molten resin is injected into the mold 300, thereby forming the insulating resin 60 on the surface of the wire winding 50. For example, a thermoplastic resin such as ABS (Acrylonitrile Butadiene Styrene) resin is used as the insulating resin 60, but the insulating resin 60 is not particularly limited thereto and the type of insulating resin 60 can be changed as appropriate.

[0047] [Stator manufacturing method] Fig. 5 is an explanatory diagram of the insulation coating process. Fig. 6A is a schematic view of the tooth and wire winding set in the mold as viewed from the axial direction. Fig. 6B is a schematic view of the tooth and wire winding set in the mold as viewed from the radially inner side. Note that the directions shown in Figs. 6A and 6B are the directions when the tooth 10 is assembled into the motor 1000.

[0048] Hereinafter, a method for manufacturing the stator 100 will be described with reference to the drawings. First, the wire winding body 50 having the grooves 53 formed therein is prepared, and the wire winding body 50 is attached to the tooth 10.

[0049] Next, as shown on the left side of Fig. 5, the tooth 10 with the wire winding body 50 attached is set in a mold 300. The mold 300 is a normal split type. The mold 300 is split into a cavity 310, which is a fixed part, and a core 320, which is a movable part. A resin injection passage 311 is provided in the cavity 310.

[0050] The tooth 10 is set at a predetermined position on the core 320 and held and fixed by the slide core 400. The lead portion 52 of the wire winding body 50 is also positioned and held by the core 320. In this state, the core 320 moves toward the cavity 310, and the cavity 310 and the core 320 come into contact at the parting line PL, sealing the wire winding body 50 and the tooth 10 inside the mold 300.

[0051] At this time, as shown in Figures 6A and 6B, the positioning pin 420 and the slide core 410 each abut against a predetermined position on the wire winding body 50, for example, a recess 56 (see Figure 17) described later, thereby positioning the wire winding body 50 relative to the tooth 10 and providing a predetermined gap between the inner surface of the wire winding body 50 and the surface of the tooth 10.

[0052] Next, molten thermoplastic resin is poured into the injection passage 311 to resin-mold the wire winding body 50 and the tooth 10. At this time, the resin enters the grooves 53 of the wire winding body 50, and the resin inflow pressure spreads the spaces between adjacent turns in the radial direction, so that the resin flows around to cover the entire surface of the wire winding part. Note that the resin does not flow around the part of the lead part 52 held by the core 320.

[0053] After the resin is injected, the core 320 is allowed to cool to a predetermined temperature or below, and then the core 320 is moved away from the cavity 310. The wire winding body 50 and the tooth 10 are removed from the core 320, completing the insulating coating process for the wire winding body 50 and completing the coil 40. This process is a so-called insert molding process. Note that the shapes of the cavity 310 and the core 320, the positions at which the tooth 10 and the wire winding body 50 are set on the core 320, and the position and shape of the parting line PL are set so that burrs of the insulating resin 60 remain on the coil 40 as little as possible.

[0054] Fig. 7 is a schematic cross-sectional view of a main part of the stator. The structure shown in Fig. 7 is the structure after the insulating coating process is completed.

[0055] 7, insulating resin 60 is filled between the inner circumferential surface of wire winding body 50 and the surface of tooth 10, and is formed so as to integrally cover wire winding body 50 and tooth 10. In other words, insulating resin 60 provided on the inner circumferential surface of wire winding body 50 contacts the surface of tooth 10, and coil 40 is fixed to tooth 10.

[0056] The insulating resin 60 is formed to continuously cover the spaces between adjacent turns of the wire winding body 50, the outer and inner surfaces of the wire winding body 50, and both end faces in the radial direction, which is the stacking direction of the wire.

[0057] [Effects, etc.] As described above, the coil 40 according to this embodiment comprises at least a wire winding body 50 in which a wire made of a conductor having a rectangular cross section is wound and laminated for n turns (n ​​is a natural number), and an insulating resin 60 covering the surface of the wire winding body 50.

[0058] The i-th turn is a quadrangular ring having four sides 51, and in the i-th turn, the insulating resin 60 covers the surfaces of each of the four sides 51. In the first to n-th turns, the insulating resin 60 is formed continuously and integrally.

[0059] Grooves 53a, 53b are provided on each of the four side portions 51 included in the i-th turn, and extend from the outer peripheral surface to the inner peripheral surface of the wire winding body 50. The insulating resin 60 covers the surfaces of the four side portions 51 and is formed to fill the grooves 53, 53a, or 53b.

[0060] By configuring the coil 40 in this manner, the manufacturing costs of the coil 40, particularly the cost of forming an insulating coating on the surface of the wire winding body 50, can be significantly reduced.

[0061] As described above, coil 40 of the present embodiment includes at least wire winding body 50 in which a wire made of a conductor having a rectangular cross section is wound and laminated for n turns (n ​​is a natural number), and insulating resin 60 that covers the surface of wire winding body 50, with insulating resin 60 covering the surface of the annular i-th turn (i is an integer, 1≦i≦n), and insulating resin 60 is formed continuously and integrally in turns 1 to n. As a result, coil 40 of the present disclosure can significantly reduce the manufacturing costs of coil 40, particularly the cost of forming an insulating coating on the surface of wire winding body 50.

[0062] 8 is a perspective view of a coil 40A for comparison purposes. The configuration of the coil 40A shown in FIG. 8 corresponds to the conventional configuration disclosed in Patent Document 1, for example.

[0063] In the coil 40A shown in FIG. 8, the wire winding body 50A does not have the grooves 53a and 53b shown in FIGS. 2 to 4. When the insulating resin 60 is formed on the surface of this wire winding body 50A by the method described above, the gap between adjacent turns in the radial direction is narrow, making it difficult for molten resin with a predetermined viscosity to penetrate into the gap. As a result, the insulating resin 60 is not formed to the desired thickness between adjacent turns. Alternatively, the thickness of the insulating resin 60 varies. This could result in poor insulation of the coil 40A.

[0064] On the other hand, according to this embodiment, grooves 53a, 53b are provided on each of the four sides 51 included in the i-th turn, extending from the outer circumferential surface of the wire winding 50 to the inner circumferential surface. This allows the molten resin to easily enter the grooves 53 during the insulation coating process. Furthermore, the inflow pressure of the resin spreads the gap between adjacent turns, allowing the molten resin to fully flow around. This ensures that the entire surface of the wire winding 50 is covered with the insulating resin 60. This prevents poor insulation of the coil 40.

[0065] Furthermore, since the entire surface of the wire winding body 50 can be coated with the insulating resin 60 at once by known insert molding, the manufacturing costs of the insulating coating, and therefore the manufacturing costs of the coil 40, can be reduced.

[0066] In this embodiment, the case where the i-th turn of the wire winding body 50 is a square ring is described as an example, but this is not particularly limited. The i-th turn may be a ring, including a circular ring or a regular polygonal ring, and the surfaces of the first to n-th turns may be covered with the insulating resin 60. In this case, too, the insulating resin 60 is formed continuously and integrally in the first to n-th turns. In other words, the insulating resin 60 is integrated in the first to n-th turns. In this case, the grooves 53 are preferably provided at positions facing each other in the radial direction across an imaginary axis that passes through the center of the wire winding body 50 and extends in the axial direction.

[0067] The stator 100 includes at least a stator core 110 having teeth (tooth portions) 10 and a coil 40.

[0068] The insulating resin 60 is formed so as to integrally cover the wire winding body 50 and the teeth (tooth portions) 10. The insulating resin 60 is also formed so as to continuously cover the spaces between adjacent turns of the wire winding body 50, the outer peripheral surface and inner peripheral surface of the wire winding body 50, and both end surfaces in the radial direction, which is the stacking direction of the wire.

[0069] By configuring the stator 100 in this manner, the insulating coating process in the manufacturing process of the coil 40 can be used in common with part of the assembly process of the stator 100, thereby reducing the manufacturing cost of the stator 100. In addition, insulation failure of the coil 40 can be reduced, and the reliability of the stator 100 can be improved.

[0070] The insulating resin 60 provided on the inner peripheral surface of the wire winding body 50 contacts the surface of the tooth 10, and the coil 40 is fixed to the tooth 10.

[0071] This makes it possible to omit an insulator (not shown) for electrically insulating the stator core 110 including the teeth 10 from the coil 40, thereby reducing the cost of the stator 100. From the viewpoint of ensuring electrical insulation, it is preferable that the insulating resin 60 provided on the inner peripheral surface of the coil 40 be formed to be thicker than the insulating resin 60 provided on the outer peripheral surface of the coil 40 or the insulating resin 60 provided on either of the end faces in the lamination direction of the wire.

[0072] However, depending on the required specifications regarding the size of the slot 30 or the insulating properties between the stator core 110 and the coil 40, the wire winding body 50 may be attached to the tooth 10 to which the insulator described above is attached, and the insulating resin 60 may be formed by the method described above.

[0073] The coil 40 may be formed in advance by covering the wire winding body 50 with the insulating resin 60, and then attached to the tooth 10. When attaching the coil 40, the insulator described above may be attached to the tooth 10 in advance.

[0074] The yoke 20 may also be divided into multiple pieces in the circumferential direction. In this case, teeth 10 with coils 40 attached thereto are connected to each of the divided yokes (not shown). The stator 100 is then completed by connecting the divided yokes in the circumferential direction.

[0075] When using a split yoke, the split yoke to which the teeth 10 are connected and the wire winding body 50 may be set in a mold 300 shown in Figures 5, 6A, and 6B to form the insulating resin 60. This increases the degree of process freedom in the assembly process of the stator 100.

[0076] The stator 100 according to this embodiment includes at least a stator core 110 having teeth 10, a wire winding body 50 in which a wire made of a conductor having a rectangular cross section is wound and laminated for n turns (n ​​is a natural number), and a coil 40 having insulating resin 60 covering the surface of the wire winding body 50, the insulating resin 60 being formed so as to continuously cover at least the outer peripheral surface, the inner peripheral surface, and both end faces in the lamination direction of the wire of the wire winding body 50, and an insulating material being provided between adjacent turns. The stator 100 according to this embodiment can reduce the manufacturing cost of the stator 100.

[0077] The motor 1000 according to this embodiment includes at least a rotor 200 having an output shaft 210 at its axis, and a stator 100 that is coaxial with the rotor 200 and spaced a predetermined distance from the rotor 200 .

[0078] By configuring the motor 1000 in this manner, it is possible to reduce the cost of the stator 100, and therefore the cost of the motor 1000. Furthermore, it is possible to reduce insulation failures of the coils 40, and the reliability of the motor 1000 is improved.

[0079] <Variation 1> Fig. 9 is a perspective view of a first wire winding body according to Modification 1. Fig. 10 is a perspective view of a second wire winding body according to Modification 1. Fig. 11 is a perspective view of a third wire winding body according to Modification 1. Fig. 12 is a perspective view of a fourth wire winding body according to Modification 1. In Figs. 9 to 12 and the subsequent drawings, parts that are the same as those in embodiment 1 are given the same reference numerals, and detailed description thereof will be omitted.

[0080] The shape, number, and arrangement of the grooves provided in the wire winding body 50 are not particularly limited to the configuration shown in the first embodiment, and can be variously changed as shown in this modified example.

[0081] For example, as shown in Fig. 9, grooves 53a (53) may be provided only on the radial outer circumferential surface of side portion 51. Also, as shown in Fig. 10, two grooves 53a and two grooves 53b may be provided on each of the four side portions 51.

[0082] That is, in coil 40 according to the present disclosure, one or more grooves 53a, 53b are provided on each of four side portions 51 included in at least the j-th turn (j is an integer and 2≦j≦n−1), the grooves extending from the outer circumferential surface to the inner circumferential surface of wire winding body 50. Three or more grooves may be formed on one side portion 51.

[0083] 11, another groove 54c may be further provided extending along the stacking direction so as to connect between a plurality of grooves 54a, 54b arranged at a distance in the radial direction, which is the stacking direction of the wire. The grooves 54c are provided on the inner circumferential surface and the outer circumferential surface of the wire winding body 50. In other words, the grooves 54 are made up of the grooves 54a, 54b facing each other in the radial direction, the groove 54c connecting the inner circumferential ends of these grooves, and the groove 54c connecting the outer circumferential ends of these grooves.

[0084] By providing grooves 54, insulating resin 60 can easily enter between adjacent turns during the insulating coating process. This ensures that the entire surface of wire winding body 50 is covered with insulating resin 60. This reliably reduces insulation defects in coil 40, improving the reliability of stator 100 and, ultimately, motor 1000.

[0085] Note that providing grooves 54c reduces the cross-sectional area of ​​the wire, increasing the rate at which the electrical resistance of coil 40 increases. Therefore, the width and depth of grooves 54c can be changed as appropriate depending on the electrical resistance specifications required of coil 40. As shown in FIG. 10 , increasing the number of grooves 53 also increases the rate at which the electrical resistance of coil 40 increases. Therefore, the width and depth of each groove can be changed as appropriate depending on the electrical resistance specifications required of coil 40.

[0086] 11, in order to facilitate the penetration of insulating resin 60, groove 54c is preferably provided on either the outer circumferential surface or the inner circumferential surface of wire winding body 50 into which insulating resin 60 flows. In other words, groove 54c may be formed so as to be continuous with one end of grooves 54a, 54b.

[0087] 12 , among the four side portions 51 included in the ith turn, a pair of opposing side portions 51 may each be provided with grooves 55a, 55b that extend from one end of the side portion 51 to the other end. In this case, both ends of the grooves 55a, 55b are provided on the outer circumferential surface of the wire winding body 50. In adjacent turns, the grooves 55a and 55b are arranged opposite each other to form one groove 55.

[0088] Even when grooves 55 are formed in this manner, insulating resin 60 can easily penetrate between adjacent turns. This ensures that the entire surface of wire winding body 50 is covered with insulating resin 60. This reliably reduces insulation failures of coil 40. This improves the reliability of stator 100, and ultimately motor 1000.

[0089] The number of grooves 55a, 55b formed in side portion 51 may be two or more. Furthermore, grooves 55a, 55b reaching from one end of side portion 51 to the other may be provided in each of a pair of opposing side portions 51 in which no grooves are formed in FIG. 12 . In this case, both ends of grooves 55a, 55b are provided on the outer peripheral surface of wire winding body 50. The longitudinal direction of grooves 55a, 55b is preferably aligned with the flow direction of molten resin within mold 300. This allows insulating resin 60 to more easily penetrate between adjacent turns, ensuring that the entire surface of wire winding body 50 is covered with insulating resin 60.

[0090] 9 to 11, the i-th turn may be formed in a circular or regular polygonal ring shape, and the surfaces of the 1st to n-th turns may be covered with insulating resin 60. In this case, the grooves are preferably provided at positions that face each other in the radial direction across an imaginary axis that passes through the center of wire winding body 50 and extends in the axial direction.

[0091] As described above, in the coil of this modified example, the i-th turn is a square ring having four side portions 51, and in the i-th turn, the insulating resin 60 covers the surface of each of the four side portions 51, and at least one or more groove portions 55a, 55b reaching from one end of the side portion 51 to the other end are provided in one or two sets of mutually opposing side portions 51 of the four side portions 51 included in the j-th turn.

[0092] The grooves 55a and 55b may also have a tapered shape in which at least one of the width and depth changes from one end of the side 51 to the other end.

[0093] In addition, another groove portion 54c extending along the stacking direction of the wires may be further provided on at least one of the outer peripheral surface and inner peripheral surface of the wire winding body 50, and the other groove portion 54c may be formed so as to be connected to one end of the groove portion.

[0094] <Variation 2> Fig. 13A is a top view of a side portion of a wire winding body according to Modification 2. Fig. 13B is a top view of a side portion of another wire winding body according to Modification 2. Note that groove 53a1 shown in Fig. 13A corresponds to groove 53a shown in Fig. 2. Groove 55a1 shown in Fig. 13B corresponds to groove 55a shown in Fig. 12.

[0095] In order to make it easier for insulating resin 60 to penetrate between adjacent turns of wire winding body 50, as shown in Figures 13A and 13B, grooves 53a1 and 55a1 may be tapered so that their width changes from the outer peripheral surface to the inner peripheral surface of wire winding body 50.

[0096] 13A, it is preferable that groove 53a1 be widest at the outer circumferential surface of wire winding body 50, which is the inflow surface for the molten resin, and that groove 53a1 be narrower toward the inner circumferential surface. This allows insulating resin 60 to easily enter between adjacent turns, ensuring that the entire surface of wire winding body 50 is covered with insulating resin 60. This reliably reduces insulation defects in coil 40 and improves the reliability of stator 100 and, ultimately, motor 1000.

[0097] When the inflow surface of the molten resin is the inner peripheral surface of the wire winding body 50, it goes without saying that it is preferable that the width of the groove portion 53a1 is widest at the inner peripheral surface and that the width of the groove portion 53a1 narrows toward the outer peripheral surface.

[0098] Similarly, in the configuration shown in FIG. 13B, it goes without saying that it is preferable that the width of groove portion 55a1, which corresponds to the inflow surface of the molten resin, is widest at one end and that the width of groove portion 55a1 narrows toward the other end.

[0099] In the configuration shown in FIG. 13A, the i-th turn may be formed in a circular or regular polygonal ring shape, and the surfaces of the first to n-th turns may be covered with insulating resin 60.

[0100] <Variation 3> Fig. 14A is a schematic cross-sectional view of a side portion of a wire winding body according to Modification 3. Fig. 14B is a schematic cross-sectional view of a side portion of another wire winding body according to Modification 3. Note that groove 53a2 shown in Fig. 14A corresponds to groove 53a shown in Fig. 2. Groove 55a2 shown in Fig. 14B corresponds to groove 55a shown in Fig. 12.

[0101] In order to make it easier for insulating resin 60 to penetrate between adjacent turns of wire winding body 50, as shown in Figures 14A and 14B, grooves 53a2, 55a2 may be shaped in a tapered shape whose depth changes from the outer peripheral surface to the inner peripheral surface of wire winding body 50.

[0102] 14A, it is preferable that the grooves 53a2 are deepest at the outer peripheral surface of the wire winding body 50, which is the inflow surface for the molten resin, and that the width of the grooves 53a2 become shallower toward the inner peripheral surface. This allows the insulating resin 60 to easily penetrate between adjacent turns. This ensures that the entire surface of the wire winding body 50 is covered with the insulating resin 60. This reliably reduces insulation failures of the coil 40. This improves the reliability of the stator 100 and, ultimately, the motor 1000.

[0103] When the surface into which the molten resin flows is the inner peripheral surface of the wire winding body 50, it goes without saying that it is preferable that the depth of the groove portion 53a2 is greatest at the inner peripheral surface and that the width of the groove portion 53a2 narrows toward the outer peripheral surface.

[0104] Similarly, in the configuration shown in FIG. 14B, it goes without saying that it is preferable that the depth of groove portion 55a2 is greatest at one end corresponding to the inflow surface of the molten resin, and that the depth of groove portion 55a2 becomes shallower toward the other end.

[0105] In the configuration shown in FIG. 14A, the i-th turn may be formed in a circular or regular polygonal ring shape, and the insulating resin 60 may cover the surfaces of the first to n-th turns.

[0106] <Variation 4> Fig. 15 is a perspective view of a wire winding body according to Modification 4. Fig. 16 is a partially enlarged view of another wire winding body according to Modification 4.

[0107] The configuration of this modified example shown in FIGS. 15 and 16 differs from the configuration shown in embodiment 1 in that an insulating material different from insulating resin 60 is provided between adjacent turns of wire winding body 50.

[0108] Depending on the required performance specifications of the stator 100 and the size constraints of the coil 40, it may be necessary to reduce the thickness of the insulating resin 60, particularly the thickness of the insulating resin 60 provided between adjacent turns of the wire winding 50, or to suppress thickness variations. In such cases, as shown in the first embodiment, it may be difficult to control the thickness of the insulating resin 60 provided between adjacent turns by the inflow pressure or inflow amount of the molten resin.

[0109] According to this modification, this problem can be addressed by providing an insulating material different from the insulating resin 60 between adjacent turns of the wire winding 50 in advance. For example, as shown in FIG. 15 , insulating paper 61 may be sandwiched between adjacent turns. That is, the insulating material may be the insulating paper 61. Also, as shown in FIG. 16 , a plurality of dot-shaped insulators 62 may be provided at intervals between adjacent turns by inkjet printing or the like. In this way, the thickness of the insulating resin 60 provided between adjacent turns can be set to a desired value.

[0110] 15 and 16, insulating resin 60 is formed on the surface of wire winding body 50 by the method described in embodiment 1. Therefore, insulating resin 60 may be embedded between dot-shaped insulators 62 shown in FIG. 16. This configuration reliably prevents insulation failure of coil 40. This improves the reliability of stator 100 and, ultimately, motor 1000.

[0111] That is, in the stator 100 according to the present disclosure, an insulating material is provided between adjacent turns of the wire winding body 50. The insulating material may be only the insulating resin 60, or may include an insulating member different from the insulating resin 60 in addition to the insulating resin 60.

[0112] 16 is not particularly limited to a specific shape. If the thickness can be controlled, the insulators 62 may be formed by potting. The spacing between the insulators 62 may also be changed as appropriate.

[0113] In this modification, the i-th turn may be formed in a circular or regular polygonal ring shape, and the insulating resin 60 may cover the surfaces of the first to n-th turns.

[0114] (Embodiment 2) Fig. 17 is a side view of a wire winding body 50 according to embodiment 2. Fig. 18 is a partial cross-sectional view of a coil 40 according to embodiment 2. Fig. 19 is a side view of another wire winding body 50 according to embodiment 2. Fig. 20A is a side view of yet another wire winding body 50 according to embodiment 2. Fig. 20B is a cross-sectional view taken along line XXB-XXB in Fig. 20A.

[0115] As shown in Fig. 17, the wire winding body 50 shown in this embodiment differs from the configuration shown in the first embodiment in that recesses 56 recessed from the outer peripheral surface toward the inner peripheral surface of the wire winding body 50 are provided at the four corners of the outer peripheral surface of each of two adjacent turns. The recesses 56 are formed by linearly cutting out the four corners of the outer peripheral surface. As a result, the recesses 56 have substantially triangular flat surfaces at the corners of the wire winding body 50. In other words, the recesses 56 have a shape that is substantially a triangular pyramid cut out from the corners of the wire winding body 50.

[0116] By configuring the wire winding body 50 in this manner, it becomes easy to provide the insulating resin 60 between adjacent turns in the insulating coating step shown in Fig. 5. This will be further explained.

[0117] As described above, in the insulation coating process, as shown in Figures 6A and 6B, the slide core 410 abuts against the wire winding body 50 to fix the position of the wire winding body 50. At this time, the tip of the slide core 410 abuts against the recesses 56 provided at the four corners of the outer circumferential surface of each of two adjacent turns. In the following description, the slide core 410 may also be referred to as the pressing portion 410.

[0118] In this state, when the pressing portion 410 is pressed toward the inner peripheral surface of the wire winding body 50, a predetermined gap is provided between two adjacent turns, as shown in Fig. 18. Subsequently, molten resin is injected and the temperature is further lowered, thereby forming insulating resin 60 between the two adjacent turns.

[0119] This embodiment achieves the same effects as the configuration shown in embodiment 1. That is, it is possible to significantly reduce the manufacturing cost of the coil 40, particularly the cost of forming an insulating coating on the surface of the wire winding body 50. Furthermore, it is possible to reliably cover the surface of the wire winding body 50 with the insulating resin 60. This reliably reduces insulation defects in the coil 40. Therefore, the reliability of the stator 100, and ultimately the motor 1000, is improved.

[0120] During the insulation coating process, the tip of the pressing portion 410 abuts against the recess 56, so that the insulating resin 60 is not formed on the outer periphery of the two adjacent turns, including the surface of the recess 56. However, because the two adjacent turns are spaced apart, the occurrence of insulation defects in the coil 40 is suppressed.

[0121] Furthermore, the pressing portion 410 abuts against the recess 56, pushing apart the space between two adjacent turns. Therefore, the thickness of the insulating resin 60 provided between the two turns is equal to or less than the width of the recess 56 along the radial direction, which is the lamination direction of the turns, making it easy to control the thickness of the insulating resin 60.

[0122] The shape of the recess 56 is not particularly limited to the example shown in Fig. 17. For example, as shown in Fig. 19, recesses 57 that are square in side view may be provided at the four corners of the outer circumferential surfaces of two adjacent turns.

[0123] 20A and 20B, in two adjacent turns, the opposing sides on the outer circumferential surface of the side portions 51, i.e., the upper side of one side portion 51 and the lower side of the other side portion 51, may be chamfered from one end to the other end of each side portion 51. In other words, the upper side of one side portion 51 and the lower side of the other side portion 51 may have a chamfered portion 58 formed from one end to the other end of each side portion 51.

[0124] This allows the insulating resin 60 to more easily penetrate between two adjacent turns, ensuring that the surface of the wire winding body 50 is covered with the insulating resin 60. This reliably reduces insulation failures in the coil 40. This improves the reliability of the stator 100, and ultimately the motor 1000.

[0125] Depending on the size or shape of the tip of the pressing portion 410, one of the opposing sides on the outer peripheral surface of the side portion 51, i.e., the upper side of one side portion 51 or the lower side of the other side portion 51, may be chamfered from one end of the side portion 51 to the other end.

[0126] In the example shown in FIG. 20B, opposing sides on the outer circumferential surface of side portion 51 are chamfered linearly, but this is not particularly limited, and for example, they may be rounded.

[0127] As described above, in the coil of this embodiment, the i-th turn is a square ring having four side portions 51, and in the i-th turn, the insulating resin 60 covers the surface of each of the four side portions 51. At least four corners of the outer surface of each of two turns adjacent to each other in the stacking direction of the wire are provided with recesses 56 recessed from the outer surface toward the inner surface of the wire winding 50, and it is preferable that the thickness of the insulating resin provided between the two turns is equal to or less than the width of the recesses 56 along the stacking direction.

[0128] Furthermore, the i-th turn (i is an integer, 1≦i≦n) is a square ring having four sides, and in the i-th turn, the insulating resin 60 covers the surface of each of the four sides 51, and in two turns adjacent to each other in the stacking direction of the wire, at least one of the upper and lower sides of the outer surface of the side 51 may be chamfered from one end of the side 51 to the other end.

[0129] (Other embodiments) The components disclosed in the first and second embodiments and the modifications may be combined as appropriate to create new embodiments. For example, the recess 56 shown in the modification 3 may be formed in the wire winding body 50 shown in the first embodiment or the first and second modifications. [Industrial Applicability]

[0130] The coil according to the present disclosure is useful as a low-cost formed coil because it can reduce the manufacturing cost of the insulating coating. [Explanation of symbols]

[0131] 10 Tooth 20 York 30 slots 40 coils 50,50A wire wound body 51 Side 52 Lead section 53,53a,53b,53a1,53a2 Groove 54,54a,54b,54c Groove 55,55a,55b,55a1,55a2 Groove 56,57 Recess 58 Chamfered part 60 Insulating resin 61 Insulating paper 62 Insulators 100 Stator 110 stator core 200 rotors 210 output shaft 220 rotor core 230 Magnet 300 molds 310 cavity 311 Injection path 320 cores 400,410 Slide core (pressure part) 420 Locating Pin 1000 motor

Claims

1. a wire winding body in which a wire made of a conductor having a rectangular cross section is wound and laminated for n turns (n ​​is a natural number); and an insulating resin covering the surface of the wire winding body, wherein the insulating resin covers the surface of the annular i-th turn (i is an integer, 1≦i≦n), the insulating resin is formed continuously and integrally in the 1st to nth turns, and one or more grooves extending from the outer circumferential surface of the wire winding body to the inner circumferential surface are provided in at least the j-th turn (j is an integer, 2≦j≦n-1), and the insulating resin is formed so as to fill the grooves.

2. 2. The coil according to claim 1, wherein the i-th turn is a square ring having four sides, the insulating resin covers the surfaces of each of the four sides in the i-th turn, and one or more grooves are provided on each of the four sides included in at least the j-th turn.

3. 3. The coil according to claim 1, wherein the groove has a tapered shape in which at least one of a width and a depth changes from an outer circumferential surface to an inner circumferential surface of the wire winding body.

4. 2. The coil of claim 1, wherein a plurality of grooves are provided in at least the jth turn (j is an integer, 2≦j≦n-1), both ends of the grooves are provided on the outer peripheral surface of the jth turn, and the insulating resin is formed so as to fill the grooves.

5. 5. The coil according to claim 4, wherein the i-th turn is a square ring having four sides, the insulating resin covers the surfaces of each of the four sides in the i-th turn, and one or more grooves are provided in each of one or two pairs of mutually opposing sides of at least the four sides included in the j-th turn, the grooves extending from one end of the side to the other end.

6. 6. The coil according to claim 5, wherein the groove has a tapered shape in which at least one of a width and a depth changes from one end of the side portion to the other end.

7. 5. The coil according to claim 1, wherein the outer circumferential surface and the inner circumferential surface of the wire winding body are A coil in which another groove portion is further provided on at least one of the faces, extending along the stacking direction of the wires, and the another groove portion is formed so as to be connected to one end of the groove portion.

8. 2. The coil according to claim 1, wherein the i-th turn is a square ring having four sides, the insulating resin covers the surfaces of each of the four sides of the i-th turn, at least four corners of the outer peripheral surface of each of two turns adjacent to each other in the stacking direction of the wire are provided with a recess extending from the outer peripheral surface of the wire winding body toward the inner peripheral surface, and the thickness of the insulating resin provided between the two turns is less than or equal to the width of the recess along the stacking direction.

9. 2. The coil according to claim 1, wherein the i-th turn (i is an integer, 1≦i≦n) is a square ring having four sides, the insulating resin covers the surfaces of each of the four sides in the i-th turn, and in two turns adjacent to each other in the stacking direction of the wire, at least one of the upper and lower sides of the outer peripheral surface of the side is chamfered from one end of the side to the other end.

10. 2. A stator comprising: a stator core having teeth; and the coil according to claim 1, wherein the insulating resin is formed so as to continuously cover at least the outer peripheral surface and the inner peripheral surface of the wire winding body and both end faces in the stacking direction of the wire, and an insulating material is provided between adjacent turns.

11. A stator comprising a stator core having teeth and the coil according to any one of claims 1 to 6, wherein the insulating resin is formed so as to continuously cover an outer peripheral surface, an inner peripheral surface, and both end faces in a stacking direction of the wire.

12. 11. The stator according to claim 10, wherein the insulating material provided between adjacent turns includes a material different from the insulating resin.

13. 13. The stator according to claim 12, wherein the insulating material is insulating paper.

14. 13. The stator according to claim 12, wherein the insulating material is provided in a plurality of portions spaced apart from each other between adjacent turns.

15. 15. The stator according to claim 10, wherein the insulating resin provided on the inner peripheral surface of the coil is in contact with the surface of the tooth portion, and the coil is fixed to the tooth portion.

16. 16. The stator of claim 15, wherein the insulating resin provided on the inner peripheral surface of the coil is formed to be thicker than the insulating resin provided on the outer peripheral surface of the coil or the insulating resin provided on either of both end faces in the stacking direction of the wire.

17. A motor comprising at least a rotor having an output shaft as its axis, and the stator according to any one of claims 10 to 16, which is coaxial with the rotor and spaced a predetermined distance from the rotor.

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