Stator and motor
The stator design with partially positioned insulating members between adjacent coils addresses the heat dissipation reduction issue by ensuring insulation and heat transfer efficiency in motor stators.
Patent Information
- Application Number
- JP2024059135
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-04-01
- Publication Date
- 2025-10-14
AI Technical Summary
Conventional motor stators with insulating sheets reduce heat dissipation performance due to their radial dimension being equal to or larger than the coil, obstructing effective heat dissipation.
The stator design includes insulating members provided partially along the radial and axial lengths of the coils, positioned between adjacent coils where they are closest, ensuring insulation while maintaining heat dissipation paths through a molded resin with higher thermal conductivity.
This configuration maintains insulation distances and prevents a decrease in heat dissipation performance by restricting coil movement and enhancing heat transfer to the resin, thereby improving overall thermal management.
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Figure 2025155342000001_ABST
Abstract
Description
[Technical Field]
[0001] The present disclosure relates to a stator and a motor. [Background technology]
[0002] Conventionally, some motor stators include an insulating sheet interposed between coils in slots, which are spaces formed between circumferentially adjacent teeth (see, for example, Patent Document 1). In the stator of Patent Document 1, the radial dimension of the insulating sheet is set to be equal to or larger than the radial dimension of the coil. This allows the insulating sheet to face the entire radial dimension of the coil in the circumferential direction. [Prior art documents] [Patent documents]
[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-30158 Summary of the Invention [Problem to be solved by the invention]
[0004] The stator described above has a problem in that the heat dissipation performance of the coil is reduced by the insulating sheet. An object of the present disclosure is to provide a stator and a motor that can suppress a decrease in heat dissipation performance. [Means for solving the problem]
[0005] A stator that solves the above problem is a stator (11) that includes a stator core (20) having a plurality of teeth (22) in the circumferential direction, coils (40) wound concentrically around each of the teeth, slots (S) that are spaces formed between adjacent teeth in the circumferential direction and through which parts of the coils pass, and insulating members (50) that are provided within the slots and between adjacent coils in the circumferential direction, where the insulating members are provided partially along the radial length of the coils and are provided between the coils at points (40X) where adjacent coils in the circumferential direction are closest to each other.
[0006] A motor that solves the above problem is a motor (10) that includes a stator (11) and a rotor (12) that faces the stator, wherein the stator includes a stator core (20) that has a plurality of teeth (22) in the circumferential direction, coils (40) that are wound concentrically around each of the teeth, slots (S) that are spaces formed between the circumferentially adjacent teeth and through which part of the coil passes, and insulating members (50) that are provided within the slots and between the circumferentially adjacent coils, wherein the insulating members are provided partially along the radial length of the coils and are provided between the coils at the points (40X) where the circumferentially adjacent coils are closest to each other.
[0007] According to the above configuration, the insulating member is interposed at the point where the circumferentially adjacent coils are closest to each other, thereby ensuring the insulation distance between the coils at that point. Furthermore, since the insulating member is provided partially along the radial length of the coil, it is possible to prevent the insulating member from reducing the heat dissipation performance of the coil. [Brief explanation of the drawings]
[0008] [Figure 1] FIG. 1 is a schematic configuration diagram of a motor according to an embodiment. [Figure 2] FIG. 2 is a perspective view showing a part of a stator in the embodiment. [Figure 3] FIG. 2 is a partial cross-sectional view of a stator in the embodiment. DETAILED DESCRIPTION OF THE INVENTION
[0009] An embodiment of a stator and a motor will be described below. (Configuration of motor 10) As shown in FIG. 1, the motor 10 includes a stator 11 and a rotor 12 facing the stator 11. The stator 11 has an annular shape. The rotor 12 is disposed inside the stator 11. That is, the rotor 12 faces the stator 11 in the radial direction. The stator 11 is housed in a cylindrical housing 13. The stator 11 is housed in the housing 13 by, for example, shrink fitting.
[0010] (Configuration of stator 11) The stator 11 includes a stator core 20, an insulator 30, a coil 40, an insulating member 50, and a molded resin 60. Note that Fig. 1 shows a schematic cross section of the insulator 30 and the coil 40.
[0011] The stator core 20 is formed of a conductor such as metal. The stator core 20 includes a plurality of split cores 20a that are divided in the circumferential direction. In this embodiment, the stator core 20 is made up of 12 split cores 20a. The stator core 20 has an annular portion 21 that is circular, and a plurality of teeth 22 that extend radially inward from the annular portion 21 in the circumferential direction. One tooth 22 is provided for each split core 20a. That is, the stator core 20 of this embodiment has 12 teeth 22.
[0012] Slots S, which are spaces formed between circumferentially adjacent teeth 22, are formed in the stator 11. The number of slots S is the same as the number of teeth 22, that is, 12 in this embodiment.
[0013] The insulators 30 are made of an insulating material such as synthetic resin. The insulators 30 are attached to each of the split cores 20a. The coils 40 are wound around the teeth 22 via the insulators 30 in a concentrated winding manner. A portion of each coil 40 passes through each slot S in the axial direction.
[0014] Three-phase AC currents, for example, with a phase difference of 120 degrees, are supplied to each coil 40. Currents of different phases are supplied to coils 40 adjacent to each other in the circumferential direction in each slot S. When power is supplied to each coil 40, a rotating magnetic field for rotating the rotor 12 is generated in the stator 11.
[0015] Fig. 2 shows a part of the stator 11. As shown in Fig. 2 and Fig. 3, the insulator 30 includes a first covering portion 31 that covers the inner circumferential surface of the annular portion 21 of the stator core 20, and a second covering portion 32 that covers the teeth 22. The second covering portion 32 covers both axial end faces and both circumferential end faces of the teeth 22.
[0016] (Configuration of coil 40) As shown in FIG. 2 , the coil 40 is formed by winding one conductor wire 41 around the outer periphery of the second covering portion 32 of the insulator 30. The conductor wire 41 forming the coil 40 includes a winding start wire 42, which is the winding start portion, and a winding end wire 43, which is the winding end portion. The winding start wire 42 is one of the conductor wires 41 located in the innermost layer of the coil 40 and is drawn out in the axial direction from the coil 40. The winding end wire 43 is one of the conductor wires 41 located in the outermost layer of the coil 40 and is drawn out in the axial direction from the coil 40. The winding start wire 42 and the winding end wire 43 are connected to, for example, a bus bar (not shown) that is arranged on a lateral side of the stator core 20 in the axial direction.
[0017] 3, the coil 40 has a conductor group 40A located in the outermost layer. The conductor group 40A includes a winding end wire 43 and an adjacent conductor wire 44 that is radially adjacent to the winding end wire 43. Note that in this embodiment, the conductor group 40A is composed of only two wires: the winding end wire 43 and the adjacent conductor wire 44.
[0018] (Configuration of insulating member 50) As shown in FIG. 1 , an insulating member 50 is disposed in each slot S. For example, one insulating member 50 is provided in each slot S. That is, the stator 11 of this embodiment includes twelve insulating members 50. Furthermore, each insulating member 50 is fixed to a corresponding coil 40.
[0019] The insulating member 50 is made of an insulator such as synthetic resin. Examples of synthetic resins that form the insulating member 50 include PPS (polyphenylene sulfide) resin. The insulating member 50 is made of a material that has lower thermal conductivity than the molded resin 60 (described later) and is more elastic than the molded resin 60.
[0020] 3, the insulating member 50 has a base 51 and a pair of clamping portions 52 extending in the same direction from the base 51. The insulating member 50 has a shape in which an opening is formed between the tips of the pair of clamping portions 52. The insulating member 50 is disposed in the slot S with the pair of clamping portions 52 facing each other in the radial direction.
[0021] The insulating member 50 is fixed to, for example, the conductor wire 41 in the outermost layer of the coil 40. More specifically, the insulating member 50 is fixed to the coil 40 by clamping together multiple conductor wires included in the conductor wire group 40A in the outermost layer with a pair of clamping portions 52. The insulating member 50 of this embodiment also holds all of the conductor wires included in the conductor wire group 40A, i.e., the winding end wire 43 and the adjacent conductor wire 44, together. This fixes the winding end wire 43 to the adjacent conductor wire 44. The insulating member 50 is fixed to the winding end wire 43 and the adjacent conductor wire 44 by snap fitting.
[0022] For example, an insertion portion 53 is formed to protrude from the tip of each clamping portion 52. The insertion portion 53 of one clamping portion 52 is inserted between the winding end wire 43 and the adjacent conductor wire 41 on the inner layer side relative to the winding end wire 43. The insertion portion 53 of the other clamping portion 52 is inserted between the adjacent conductor wire 44 and the adjacent conductor wire 41 on the inner layer side relative to the adjacent conductor wire 44. Each insertion portion 53 more firmly fixes the insulating member 50 to the coil 40.
[0023] 2, the insulating member 50 is provided partially relative to the radial length of the coil 40. The radial dimension of the insulating member 50 is set smaller than the radial dimension of the coil 40. The insulating member 50 is provided, for example, at a position closer to the radial outer side in the slot S, i.e., at a position close to the first covering portion 31 of the insulator 30.
[0024] The insulating member 50 is provided partially relative to the axial length of the coil 40. The axial dimension of the insulating member 50 is set to be smaller than the axial dimension of the slot S. The insulating member 50 is provided at a location immediately before the winding end wire 43 is pulled out from the coil 40. In other words, the insulating member 50 is provided at one axial end of the portion of the coil 40 that passes through the slot S along the axial direction.
[0025] 1, the insulating members 50 are provided between the coils 40 in each slot S at locations where the circumferentially adjacent coils 40 are closest to each other (closest locations 40X). The closest locations 40X are set, for example, at positions closer to the radial outside in the slot S. By providing the insulating members 50 between the coils 40 at the closest locations 40X, it is possible to ensure an insulation distance between the coils 40 at the closest locations 40X.
[0026] (Configuration of mold resin 60) The molded resin 60 is provided as a heat dissipation filler in the stator 11. The molded resin 60 is formed of, for example, an epoxy resin material containing alumina. It is preferable to select a material for forming the molded resin 60 that has a linear expansion coefficient close to that of the material of the insulating member 50.
[0027] The molded resin 60 is formed using a mold (not shown). That is, the molded resin 60 is formed by pouring molten resin into a mold fixed to the stator core 20 and allowing the molten resin to harden. The molded resin 60 is formed so as to cover the coils 40 and the insulators 30 collectively. That is, the winding start wire 42 and winding end wire 43 of the coil 40 and the insulating member 50 are embedded inside the molded resin 60. Note that, for ease of explanation, the molded resin 60 is not shown in FIG. 3.
[0028] The molded resin 60 includes axial covering portions 61 that cover both axial ends of the stator core 20, and intra-slot portions 62 that fit between circumferentially adjacent coils 40 in each slot S. The axial covering portion 61 is formed, for example, in an annular shape along the circumferential direction of the stator 11. The axial covering portion 61 seals the portions of the coils 40 that protrude from the axial ends of the stator core 20. The bus bars are embedded in the axial covering portions 61. The intra-slot portions 62 in each slot S are connected to the pair of axial covering portions 61 on both axial sides.
[0029] (Action of this embodiment) The operation of this embodiment will be described below. When molding the mold resin 60, the resin flows into the slot S from a position closer to the radial inside. In contrast, the insulating member 50 is provided at a position closer to the radial outside within the slot S. In other words, the insulating member 50 is provided at a position that minimizes the obstruction to the flow of the resin that forms the mold resin 60.
[0030] Furthermore, when molding the molded resin 60, the winding end wire 43 included in the outermost conductor group 40A of the coil 40 is subjected to the pressure of the flowing resin. Here, the winding end wire 43 is fixed to the adjacent conductor wires 44 by the insulating member 50. In other words, the movement of the winding end wire 43 is restricted by the insulating member 50. Therefore, when molding the molded resin 60, the winding end wire 43 is prevented from approaching the adjacent coil 40 due to the pressure of the resin. Note that, since a greater winding tension is applied to the wires of the coil 40 other than the winding end wire 43 (wires including the adjacent conductor wire 44) than to the winding end wire 43, the adjacent conductor wire 44 is less likely to loosen than the winding end wire 43.
[0031] (Effects of this embodiment) The operation of this embodiment will be described below. (1) The insulating member 50 is provided partially with respect to the radial length of the coil 40, and is provided between the coils 40 at the locations where circumferentially adjacent coils 40 are closest to each other (closest locations 40X). With this configuration, the insulating member 50 is interposed at the closest locations 40X where circumferentially adjacent coils 40 are closest to each other, thereby ensuring an insulation distance between the coils 40 at the closest locations 40X. Furthermore, because the insulating member 50 is provided partially with respect to the radial length of the coil 40, it is possible to prevent the insulating member 50 from reducing the heat dissipation performance of the coil 40.
[0032] (2) The insulating member 50 is provided partially along the axial length of the coil 40. With this configuration, the insulating member 50 can further prevent the heat dissipation performance of the coil 40 from being reduced.
[0033] (3) One insulating member 50 is provided for each of the plurality of slots S. With this configuration, in each slot S, an insulating distance between the coils 40 at the closest point 40X can be ensured.
[0034] (4) The coil 40 has a winding end wire 43. The insulating member 50 is provided at a position corresponding to the winding end wire 43. According to this configuration, the insulating member 50 can restrict the movement of the winding end wire 43, thereby preventing the winding end wire 43 from approaching an adjacent coil 40.
[0035] (5) The coil 40 has an outermost conductor group 40A including the winding end wire 43. The insulating member 50 collectively holds multiple conductors (the winding end wire 43 and the adjacent conductor wires 44) including the winding end wire 43 in the conductor group 40A. This configuration allows the insulating member 50 to fix the winding end wire 43. This allows the insulating member 50 to more effectively restrict movement of the winding end wire 43.
[0036] (6) The insulating member 50 has a base 51 and a pair of clamping portions 52 extending from the base 51. The pair of clamping portions 52 clamp a plurality of conductors (the winding end wire 43 and the adjacent conductors 44) including the winding end wire 43 of the conductor group 40A. With this configuration, the pair of clamping portions 52 of the insulating member 50 can fix the winding end wire 43.
[0037] (7) The stator 11 includes a molded resin 60 formed to collectively cover each coil 40. The molded resin 60 includes an intra-slot portion 62 that fits between circumferentially adjacent coils 40 within the slot S. Because the insulating member 50 is provided partially along the radial length of the coil 40, it is possible to ensure a large contact area between the coil 40 and the intra-slot portion 62 within the slot S. This makes it possible to ensure a heat dissipation path that transfers heat from the coil 40 to the intra-slot portion 62.
[0038] (8) The mold resin 60 is set to have a higher thermal conductivity than the insulating member 50, so that the heat dissipation of the coil 40 can be improved. (Other embodiments) The above embodiment can be modified as follows: The above embodiment and the following modifications can be combined with each other within the scope of technical compatibility.
[0039] In the above embodiment, the outermost conductor group 40A of the coil 40 is composed of only two conductors, the winding end wire 43 and the adjacent conductor wire 44. However, this is not limiting, and the outermost conductor group 40A may include three or more conductors including the winding end wire 43. In this case, the insulating member 50 may collectively hold all of the conductors included in the outermost conductor group 40A.
[0040] The configuration of the insulating member 50, such as its shape, is not limited to that in the above embodiment, and can be changed as appropriate depending on the configuration of the stator 11. The insulating member 50 may be provided in the slot S at a position closer to the inner side in the radial direction, or in the middle position in the slot S in the radial direction.
[0041] In the above embodiment, the insulating member 50 is provided at one axial end of the portion of the coil 40 that passes through the slot S along the axial direction, but this is not particularly limited. For example, the insulating member 50 may be provided at an axial middle position of the portion of the coil 40 that passes through the slot S along the axial direction.
[0042] The axial dimension of the insulating member 50 may be set to be equal to the axial dimension of the slot S. The insulating member 50 may be fixed to a portion of the coil 40 that does not include the end winding wire 43 .
[0043] In the above embodiment, the insulating member 50 can be fixed to the coil 40 by snap fitting. However, the insulating member 50 may also be fixed to the coil 40 by other methods, such as adhesive.
[0044] In the above embodiment, the insulating member 50 is fixed to the coil 40, but this is not limiting. For example, the insulating member 50 may be fixed to the first covering portion 31 of the insulator 30 by adhesive or the like.
[0045] The insulating members 50 may be provided in only some of the slots S. The material of the insulating member 50 is not limited to that in the above embodiment, but can be changed as appropriate depending on the configuration of the stator 11.
[0046] The material of the mold resin 60 is not limited to that in the above embodiment, but can be changed as appropriate depending on the configuration of the stator 11. In the stator 11 of the above embodiment, the molded resin 60 may be omitted. If the molded resin 60 is omitted, cooling oil may be applied to the surface of the coil 40. Even in this case, the insulating member 50 is provided partially along the radial length of the coil 40, which makes it easier for the cooling oil to adhere to the surface of the coil 40, and is therefore an advantageous configuration in terms of improving the heat dissipation of the coil 40.
[0047] In the above embodiment, the stator core 20 is made up of a plurality of split cores 20a, but this is not limiting. That is, the stator core 20 may have an annular portion 21 that is connected around the entire circumference.
[0048] In the above embodiment, the stator 11 has twelve teeth 22, but the number of teeth 22 is not limited to twelve. For example, the stator 11 may have another number of teeth 22, such as twenty-four.
[0049] In the above embodiment, the stator 11 and the housing 13 are fixed to each other by shrink fitting, but this is not limitative and the stator 11 and the housing 13 may be fixed to each other by other means. While the present disclosure has been described with reference to the embodiments, it is understood that the present disclosure is not limited to those embodiments or structures. The present disclosure also encompasses various modifications and equivalent modifications. In addition, various combinations and forms, including only one element, more than one element, or less than one element, are also within the scope and spirit of the present disclosure.
[0050] (Addendum) The features of the present disclosure are as follows: [1] A stator (11) comprising a stator core (20) having a plurality of teeth (22) in the circumferential direction, coils (40) wound concentrically around each of the teeth, slots (S) that are spaces formed between adjacent teeth in the circumferential direction and through which a portion of the coil passes, and insulating members (50) provided within the slots between adjacent coils in the circumferential direction, wherein the insulating members are provided partially relative to the radial length of the coils and are provided between the coils at points (40X) where adjacent coils in the circumferential direction are closest to each other.
[0051] [2] The stator according to [1] above, wherein the insulating member is provided partially along the axial length of the coil. [3] The stator according to [1] or [2] above, wherein the insulating member is provided for each of the plurality of slots.
[0052] [4] A stator according to any one of [1] to [3] above, wherein the coil has a winding end wire (43), and the insulating member is provided at a position corresponding to the winding end wire.
[0053] [5] The stator described in [4] above, wherein the coil has an outermost layer of a group of conductors (40A) including the winding end wire, and the insulating member holds together a plurality of conductors (43, 44) including the winding end wire among the group of conductors.
[0054] [6] The stator described in [5] above, wherein the insulating member has a base (51) and a pair of clamping portions (52) extending from the base, and the pair of clamping portions clamp the plurality of conductors of the group of conductors.
[0055] [7] A stator described in any one of [1] to [6] above, further comprising a molded resin (60) formed to cover each of the coils collectively, the molded resin including an inner slot portion (62) that fits between circumferentially adjacent coils within the slot.
[0056] [8] The stator according to [7] above, wherein the molding resin has a higher thermal conductivity than the insulating member. [9] A motor (10) comprising a stator (11) and a rotor (12) facing the stator, wherein the stator comprises a stator core (20) having a plurality of teeth (22) in the circumferential direction, coils (40) wound in a concentrated manner around each of the teeth, slots (S) which are spaces formed between the circumferentially adjacent teeth and through which a portion of the coil passes, and insulating members (50) provided within the slots between the circumferentially adjacent coils, wherein the insulating members are provided partially along the radial length of the coils and are provided between the coils at the points (40X) where the circumferentially adjacent coils are closest to each other. [Explanation of symbols]
[0057] 10...motor, 11...stator, 12...rotor, 20...stator core, 22...teeth, 40...coil, 40A...outermost layer conductor group, 40X...closest point, 41...conductor, 43...end of winding wire, 44...adjacent conductor, 50...insulating member, 51...base, 52...clamping portion, 60...molded resin, 62...internal portion of slot, S...slot
Claims
1. a stator core (20) having a plurality of teeth (22) in a circumferential direction; A coil (40) wound in a concentrated manner around each of the teeth; A slot (S) is a space formed between the teeth adjacent to each other in the circumferential direction, through which a part of the coil passes; an insulating member (50) provided between the coils adjacent to each other in the circumferential direction in the slot, The insulating member is provided partially along the radial length of the coil and is provided between the coils at a location (40X) where the coils adjacent to each other in the circumferential direction are closest to each other. Stator.
2. The insulating member is provided partially along the axial length of the coil. The stator according to claim 1 .
3. The insulating member is provided in each of the plurality of slots. The stator according to claim 1 .
4. The coil has an end winding (43), The insulating member is provided at a position corresponding to the end of the winding wire. The stator according to claim 1 .
5. The coil has an outermost layer of conductor wires (40A) including the winding end wires, The insulating member collectively holds a plurality of conductor wires (43, 44) including the winding end wires of the conductor wire group.
5. The stator according to claim 4.
6. The insulating member has a base (51) and a pair of clamping portions (52) extending from the base, The pair of clamping portions clamps the plurality of conductor wires of the conductor wire group.
6. The stator according to claim 5.
7. The coil assembly further includes a molding resin (60) formed to cover the coils collectively, The molding resin includes an inner-slot portion (62) that fits between the coils adjacent to each other in the circumferential direction within the slot. The stator according to claim 1 .
8. The molding resin has a higher thermal conductivity than the insulating member.
8. The stator according to claim 7.
9. a stator (11), a rotor (12) facing the stator, A motor (10) comprising: The stator includes: a stator core (20) having a plurality of teeth (22) in a circumferential direction; A coil (40) wound in a concentrated manner around each of the teeth; A slot (S) is a space formed between the teeth adjacent to each other in the circumferential direction, through which a part of the coil passes; an insulating member (50) provided between the coils adjacent to each other in the circumferential direction in the slot, The insulating member is provided partially along the radial length of the coil and is provided between the coils at a location (40X) where the coils adjacent to each other in the circumferential direction are closest to each other. Motor.
Citation Information
Patent Citations
Stator of rotary electric machine
JP2019030158A