Stator

Abstract

To provide a stator in which variation of an insulator can be reduced while a coil is suppressed from falling even when the diameter of a conductive wire forming the coil is changed.SOLUTION: An insulator 71 includes a plurality of holding grooves 74 which are arranged at an equal interval in a first direction D1 and in which portions of a conductive wire 91 constituting the first layer of a coil 81 are disposed. A pair of holding surfaces 78a and 78b of each holding groove 74 are inclined with respect to the first direction D1 such that the distance therebetween in the first direction D1 is increased toward an opening portion 78d. The holding surfaces are in contact with the outer circumferential surface of the conductive wire 91 disposed in the holding groove 74. Each of regulation projections 75 of the insulator 71 has a contact surface 75X that is in contact with an end, in the first direction D1, of an odd-numbered layer which is the third or greater layer of the coil 81. The contact surface 75X is inclined such that an end of the contact surface 75X farther from a tooth 65, when viewed from the axial direction, is farther from the coil 81 in the first direction D1 than the other end that is closer to the tooth 65.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to a stator. [Background technology]

[0002] Conventionally, stators provided in motors include a stator core with multiple teeth and coils wound around the teeth. The coils are formed, for example, by winding multiple layers of conductor wire around the teeth via insulators attached to the stator core. The insulators are designed specifically for each diameter of the conductor wire constituting the coil, for example, to hold the first layer of the conductor wire at a constant interval along the direction from the tip to the base of the teeth. For example, the insulator described in Patent Document 1 has guide grooves that guide the first layer of the conductor wire. The guide grooves are arranged in parallel at a pitch approximately equal to the diameter of the conductor wire. The inner circumferential surface of the guide groove is arc-shaped to match the outer circumferential surface of the conductor wire. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6065436 Summary of the Invention [Problem to be solved by the invention]

[0004] In the stator described in Patent Document 1, the portion of the conductor that constitutes the first layer of the coil is arranged in the guide groove, which stabilizes the position of the conductor in the first layer in the direction from the tip to the base end of the tooth. Furthermore, in the second and subsequent layers of the coil, the conductor is guided by the conductor in the previous layer, whose position is stable, so the position in the direction from the tip to the base end of the tooth is likely to be stable. In other words, the coil is less likely to collapse.

[0005] However, if an insulator is designed specifically for each diameter of the conductor that makes up the coil, even if the shape of the stator core is the same, if the diameter of the conductor that makes up the coil is different, then a different insulator shape must be designed for each diameter of the conductor. This creates the problem of a large number of variations in insulators. This can lead to concerns about increased costs for molds used to form the insulators and increased costs for parts management.

[0006] The present invention has been made to solve the above-mentioned problems, and its purpose is to provide a stator that can reduce the variation in insulators while preventing the coil from collapsing even if the diameter of the conductor that makes up the coil is changed. [Means for solving the problem]

[0007] A stator that solves the above problem includes a stator core (61) having a first surface (63) extending along a reference axis (L1), an annular portion (66) that forms an annular shape centered on the reference axis, and a plurality of teeth (65) extending from the first surface in a direction perpendicular to the reference axis, a plurality of insulators (71, 71A, 71B) attached to the teeth, respectively, and a plurality of coils (81) configured by winding a conducting wire (91) in three or more layers around the teeth via the insulators, and each of the insulators is a first adjacent wall (72a, 72b) that covers at least a part of the first surface at a position shifted from the coil in a first direction (D1) from the tip end toward the base end of the tooth and that is adjacent to the coil in the first direction; a second adjacent wall (73a, 73b) that is shifted from the coil in a second direction (D2) from the base end toward the tip end of the tooth and that is adjacent to the coil in the second direction; and a plurality of adjacent walls (73a, 73b) that extend along a winding direction (C2) of the coil around the tooth and in which a portion of the conductor that constitutes a first layer of the coil is disposed. and a plurality of restricting protrusions (75, 75a to 75f, 75A) protruding from at least one of the first adjacent wall and the second adjacent wall in a direction approaching the coil, the retaining grooves are arranged at equal intervals in the first direction, and each of the retaining grooves has a pair of retaining surfaces (78a, 78b) that are inclined with respect to the first direction so that the interval in the first direction becomes wider as the retaining groove approaches the opening along a direction from a bottom portion (78c) of the retaining groove toward the opening. the pair of retaining surfaces contact the outer peripheral surfaces of the conductors placed in the retaining grooves, and each of the regulating protrusions has an abutment surface (75X) that abuts against an end of the coil in the first direction in three or more odd-numbered layers, and the abutment surfaces are inclined so that, when viewed from a direction along the reference axis, an end (75Xb) farther from the teeth than an end (75Xa) closer to the teeth is farther from the coil in the first direction.

[0008] According to this configuration, the pair of holding surfaces of each holding groove are inclined relative to the first direction such that the distance in the first direction increases as the distance approaches the opening along the direction from the bottom of the holding groove toward the opening. Therefore, even if the diameter of the conductor changes, as long as the conductor can be placed in contact with both of the pair of holding surfaces, the portion of the conductor that constitutes the first layer of the coil can be positioned in the first direction by the holding groove.

[0009] Furthermore, the portion of the conductor that constitutes the first layer of the coil is positioned in retaining grooves that are arranged at equal intervals in the first direction, so that it is wound around the teeth at regular intervals in the first direction. The portion of the conductor that constitutes the second layer of the coil can be wound around the teeth so that it fits into a groove-shaped portion formed by the outer surfaces of adjacent pieces of conductor in the first direction in the first layer of the coil. Therefore, the portion of the conductor that constitutes the second layer of the coil is wound around the teeth at regular intervals in the first direction. Similarly, the portions of the conductor that constitute the third and subsequent layers of the coil are positioned in the first direction by the portion of the conductor that constitutes the previously wound layer, so that they are wound around the teeth at regular intervals in the first direction.

[0010] Generally, for a given number of coil turns, the larger the diameter of the conductor, the farther the second and subsequent layers of the coil are positioned from the outer circumferential surface of the teeth as viewed from the first direction. Furthermore, for a given number of coil turns, the larger the diameter of the conductor, the greater the distance between the ends of each coil layer in the first direction from the center of the coil in the first direction. The contact surfaces of each of the restricting protrusions are inclined so that, as viewed from the axial direction, the ends of the contact surfaces farther from the teeth in the direction perpendicular to the first direction are farther from the coil in the first direction than the ends closer to the teeth. That is, the contact surfaces are inclined so that the distance between the contact surfaces and the center of the coil in the first direction increases as the contact surfaces move farther from the teeth in the direction perpendicular to the first direction as viewed from the direction along the reference axis. Therefore, even if the diameter of the conductor is changed, it is possible to wind the coil around the teeth with the same number of turns without changing the insulator. Furthermore, even if the diameter of the conductor wire is changed, the contact surface of each of the restricting protrusions can contact the end portion in the first direction of the portion of the conductor wire that constitutes an odd number of layers (three or more) of the coil.

[0011] Furthermore, for example, when a conventional insulator without a restricting protrusion is used, depending on the diameter of the conductor, a gap may form in the first direction between the end of the odd-numbered layer of the coil and the insulator. In contrast, the insulator with the above configuration has a restricting protrusion, which prevents a gap from forming in the first direction between the end of the odd-numbered layer of the coil and the insulator. Furthermore, the abutting surface abuts against the end in the first direction of the portion of the conductor that constitutes three or more odd layers of the coil, thereby preventing the end from moving away from the center of the coil in the first direction. In other words, the coil can be prevented from collapsing even if the diameter of the conductor is changed.

[0012] For these reasons, even if the diameter of the conductor constituting the coil is changed, the portion of the conductor constituting the first layer of the coil can be wound at a constant interval in the first direction. Furthermore, even if the diameter of the conductor constituting the coil is changed, the restricting protrusion having the abutment surface prevents the third and subsequent layers of the coil from collapsing. Therefore, even if the diameter of the conductor is changed, the design of the insulator does not need to be changed. Therefore, it is possible to reduce the variation in insulators while preventing the coil from collapsing even if the diameter of the conductor constituting the coil is changed. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a schematic diagram of a motor including a stator according to an embodiment; [Figure 2] 2 is a perspective view of a split core and an insulator provided in the stator shown in FIG. 1. FIG. [Figure 3] FIG. 2 is a perspective view of an insulator provided in the stator shown in FIG. [Figure 4] FIG. 2 is a perspective view of an insulator provided in the stator shown in FIG. [Figure 5] 2 is a plan view of an insulator provided in the stator shown in FIG. 1. FIG. [Figure 6] 2 is a plan view showing a part of an insulator provided in the stator shown in FIG. 1. FIG. [Figure 7] 2 is a plan view of a split core provided in the stator shown in FIG. 1 and around which a coil is wound. [Figure 8] 2 is a plan view showing a part of a split core around which a coil is wound, the split core being provided in the stator shown in FIG. 1. FIG. [Figure 9] 2 is a plan view showing a part of a split core around which a coil is wound, the split core being provided in the stator shown in FIG. 1. FIG. [Figure 10] 2 is a plan view showing a part of a split core around which a coil is wound, the split core being provided in the stator shown in FIG. 1. FIG. [Figure 11] 2 is a plan view showing a part of a split core around which a coil is wound, the split core being provided in the stator shown in FIG. 1. FIG. [Figure 12]FIG. 10 is a plan view showing a part of a stator in a modified example. [Figure 13] FIG. 10 is a plan view showing a part of a stator in a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0014] An embodiment of a stator will be described below. For ease of explanation, some components may be exaggerated or simplified in the drawings. Also, the dimensional ratios of the components may differ between drawings. In this specification, "orthogonal" does not necessarily mean strictly orthogonal, but also includes roughly orthogonal structures within the scope of the present embodiment's effects. Furthermore, the term "annular" as used herein may refer to any structure that forms a loop, i.e., a continuous shape without ends, as well as a structure that has a generally loop-shaped configuration with a C-shaped gap. Examples of "annular" shapes include, but are not limited to, circles, ellipses, and polygons with pointed or rounded corners. Furthermore, the phrase "at least one" as used herein means "one or more" of the desired options. For example, when the number of options is two, the phrase "at least one" means "only one option" or "both of two options." For another example, when the number of options is three or more, the phrase "at least one" as used herein means "only one option" or "any combination of two or more options." It should be noted that the present invention is not limited to these examples, but is defined by the scope of the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

[0015] (Overall configuration of motor 50) 1, the motor 50 includes a stator 51 and a rotor 52. The stator 51 has an annular shape. The rotor 52 is disposed, for example, inside the stator 51. The rotor 52 has a rotation shaft 53.

[0016] (Configuration of stator 51) The stator 51 includes a stator core 61 , an insulator 71 , and a plurality of coils 81 .

[0017] (Configuration of stator core 61) As shown in FIGS. 1 and 2, the stator core 61 has, for example, a plurality of split cores 62 arranged in the circumferential direction of the stator 51. The stator core 61 has, for example, 12 split cores 62. Each split core 62 is made of a magnetic metal material. Each split core 62 has a back yoke portion 64 having a first surface 63 and teeth 65 protruding from the first surface 63 in a direction perpendicular to a reference axis L1. The reference axis L1 coincides with the center of rotation of the rotating shaft 53 in the motor 50. Furthermore, the reference axis L1 coincides with the central axis of the stator core 61 in the stator core 61. The direction along the reference axis L1 is defined as an axial direction A1.

[0018] The multiple split cores 62 that make up the stator core 61 are arranged in an annular shape centered on the reference axis L1. The multiple split cores 62 are also arranged in the circumferential direction C1 around the reference axis L1 so that the back yoke portions 64 of each split core 62 form an annular shape as a whole. The circumferential direction C1 is the same direction as the circumferential direction of the stator 51. The back yoke portions 64 of the 12 split cores 62 form an annular portion 66 that forms an annular shape centered on the reference axis L1. The first surface 63 of each back yoke portion 64 forms, for example, the inner circumferential surface of the annular portion 66. That is, the annular portion 66 has a first surface 63. The first surface 63 extends along the reference axis L1.

[0019] When the multiple split cores 62 are lined up in the circumferential direction C1, the first surface 63 is a radially inner side surface of the back yoke portion 64. The "radial direction" is a direction perpendicular to the reference axis L1. The radial direction is also a direction perpendicular to the circumferential direction C1. In this state, each tooth 65 protrudes radially inward from each back yoke portion 64. Furthermore, in this state, each tooth 65 extends along the radial direction. Furthermore, in this state, the tip of each tooth 65 is the radially inner end of each tooth 65. Furthermore, in this state, the base end of each tooth 65 is the radially outer end of each tooth 65. Each tooth 65 may have a circumferential protrusion 67 protruding from the tip region of each tooth 65 on both sides in the circumferential direction C1.

[0020] (Configuration of insulator 71 and coil 81) An insulator 71 is attached to each tooth 65. A coil 81 is wound around each tooth 65 with the insulator 71 interposed therebetween. Each coil 81 is formed by winding a conductor 91 around the tooth 65 in three or more layers with the insulator 71 interposed therebetween. Each coil 81 is formed from a single conductor 91. Two or more of the multiple coils 81 may be formed from the same single conductor 91 in succession. For example, each coil 81 is formed by winding five layers of the conductor 91 around the tooth 65 with the insulator 71 interposed therebetween. The number of layers of each coil 81 is not limited to five, as long as it is three or more. The cross-sectional shape of the conductor 91 is, for example, circular. The conductor 91 is, for example, an insulated electric wire.

[0021] The insulators 71 are used to electrically insulate the stator 51 from the coils 81 wound around the teeth 65. Each insulator 71 is made of an insulating resin material. Each insulator 71 is, for example, a resin molded product formed using a mold. For example, two insulators 71 are attached to each split core 62 from both sides in the axial direction A1. The two insulators 71 attached to each split core 62 have, for example, the same shape.

[0022] As shown in FIGS. 2 to 5, each of the insulators 71 has first adjacent walls 72a, 72b, second adjacent walls 73a, 73b, a plurality of retaining grooves 74, and a plurality of restricting protrusions 75. Each of the insulators 71 also has, for example, tooth covering portions 76 that cover at least a portion of the outer peripheral surfaces of the teeth 65. Each of the insulators 71 may also have a yoke end face covering portion 77 that covers a portion of the end face of the annular portion 66 in the axial direction A1. The yoke end face covering portion 77 covers at least a portion of the end face of the back yoke portion 64 in the axial direction A1. Each of the insulators 71 is, for example, a single component in which the first adjacent walls 72a, 72b, second adjacent walls 73a, 73b, restricting protrusions 75, tooth covering portions 76, and yoke end face covering portions 77 are integrally formed.

[0023] In each insulator 71, the tooth covering portion 76 has an end face covering portion 76a that covers one of both end faces of the tooth 65 in the axial direction A1, and side face covering portions 76b and 76c that cover both side faces in the circumferential direction C1 of the tooth 65. The side face covering portions 76b and 76c extend along the axial direction A1 from both ends of the end face covering portion 76a in the circumferential direction C1.

[0024] In each insulator 71, multiple retaining grooves 74 are provided in the tooth covering portion 76. The insulator 71 has, for example, six retaining grooves 74 extending across the side surface covering portion 76b and the end surface covering portion 76a, and six retaining grooves 74 extending across the side surface covering portion 76c and the end surface covering portion 76a. The six retaining grooves 74 extending across the side surface covering portion 76b and the end surface covering portion 76a are referred to as retaining grooves 74a to 74f. The six retaining grooves 74 extending across the side surface covering portion 76c and the end surface covering portion 76a are referred to as retaining grooves 74g to 74l.

[0025] The retaining grooves 74a to 74f are aligned in a line along a first direction D1 from the tip to the base end of the tooth 65. The retaining grooves 74a to 74f are aligned at equal intervals in the first direction D1. Similarly, the retaining grooves 74g to 74l are aligned in a line along the first direction D1. The retaining grooves 74g to 74l are aligned at equal intervals in the first direction D1. The direction from the base end to the tip of the tooth 65 is a second direction D2.

[0026] Each of the retaining grooves 74a to 74f extends over an end region including the end of the end face covering portion 76a in the circumferential direction C1 that is closer to the side face covering portion 76b, and an end region of the side face covering portion 76b in the axial direction A1 that is continuous with the end region. That is, the retaining grooves 74a to 74f are provided in a region including a corner formed by the end face covering portion 76a and the side face covering portion 76b of the tooth covering portion 76.

[0027] The retaining grooves 74g-74l extend over an end region including one of both ends of the end face covering portion 76a in the circumferential direction C1 that is closer to the side face covering portion 76c, and an end region of the side face covering portion 76c in the axial direction A1 that is continuous with the end region. That is, the retaining grooves 74g-74l are provided in a region including a corner formed by the end face covering portion 76a and the side face covering portion 76c of the tooth covering portion 76.

[0028] Each of the holding grooves 74 extends along a winding direction C2 of the coil 81 around the tooth 65. The winding direction C2 is the direction in which the conducting wire 91 constituting the coil 81 is wound around the tooth 65. The portions of each of the holding grooves 74 that are provided in the side surface covering portions 76b, 76c extend along the axial direction A1. The portions of each of the holding grooves 74 that are provided in the end surface covering portion 76a extend along a direction perpendicular to the first direction D1 when viewed from the axial direction A1.

[0029] As shown in FIGS. 5 and 6, each of the holding grooves 74 has a pair of holding surfaces 78a, 78b at both ends of the holding groove 74 in the first direction D1. In each holding groove 74, the holding surface 78b is positioned offset in the first direction D1 from the holding surface 78a. The pair of holding surfaces 78a and 78b are inclined with respect to the first direction D1 so that the distance between them in the first direction D1 increases as they approach the opening 78d along the direction from the bottom 78c of the holding groove 74 toward the opening 78d. Therefore, each of the holding surfaces 78a, 78b is not perpendicular to the first direction D1. Furthermore, each of the holding surfaces 78a, 78b is not parallel to the first direction D1.

[0030] Each of the holding grooves 74 has, for example, a V-shape in cross section. That is, each of the holding grooves 74 has, for example, a V-shape whose width in the first direction D1 increases as it approaches the opening 78d along the direction from the bottom 78c of the holding groove 74 toward the opening 78d. The cross section of the holding groove 74 is a cross section perpendicular to the direction in which the holding groove 74 extends. Note that the shape of the holding groove 74 in cross section is not limited to a V-shape and may be, for example, a trapezoidal shape. Furthermore, the shape of the bottom 78c of the holding groove 74 may be, for example, an arc shape, a flat shape extending along the first direction D1, or any other shape.

[0031] The tooth covering portions 76 have protrusions 79, for example, between adjacent retaining grooves 74 in the first direction D1. The protrusions 79 are portions between the retaining surfaces 78a and 78b adjacent in the first direction D1 in the adjacent retaining grooves 74 in the first direction D1. For example, the protrusion 79 between the retaining grooves 74a and 74b is a portion between the retaining surface 78b of the retaining groove 74a and the retaining surface 78a of the retaining groove 74b. The tip of each protrusion 79 may be rounded. For example, the tip surface of each protrusion 79 is curved in an arc shape that is convex in the protruding direction of each protrusion 79. The protruding direction of each protrusion 79 is the same direction as the direction from the bottom 78c of the retaining groove 74 toward the opening 78d.

[0032] 7, each coil 81 has a first terminal wire 82 and a second terminal wire 83. In each coil 81, the first terminal wire 82 is an end region including the winding start end of the conductor 91 that constitutes the coil 81. In each coil 81, the second terminal wire 83 is an end region including the winding end end of the conductor 91 that constitutes the coil 81.

[0033] The coil 81 shown in FIGS. 7 to 11 is illustrated in a cross section perpendicular to the reference axis L1, i.e., perpendicular to the axial direction A1. Note that the reference axis L1 is only illustrated in FIG. 1 and is therefore not illustrated in FIGS. 7 to 11. In FIGS. 7 to 11, the axial direction A1 corresponds to the direction perpendicular to the paper surface. In FIGS. 7 to 11, hatching indicating that the coil 81 is a cross section is omitted. In FIGS. 7 to 11, the reference numerals "0" to "49" written in the cross sections of the coil 81 indicate an example of the position and order in which the conductor 91 is arranged when winding the coil 81. That is, in each coil 81, the conductor 91 is wound around the teeth 65 in the order of the reference numerals "1" to "49." In addition, when viewed from the first direction D1, the conductor 91 is wound around the teeth 65 in, for example, a counterclockwise direction. Note that the conductor 91 may also be wound around the teeth 65 in a clockwise direction when viewed from the first direction D1. In each coil 81, the conducting wire 91 extends along the axial direction A1 in the portion overlapping the tooth 65 in the circumferential direction C1.

[0034] As shown in FIG. 7 , in each insulator 71, a portion of the conductor 91 constituting the first layer of the coil 81 is arranged in each of the multiple holding grooves 74. The first layer of each coil 81 is referred to as a first layer 101. For example, in each coil 81, the first layer 101 is formed by the conductor 91 arranged at positions indicated by reference numerals "0" to "11." In each coil 81, the portion of the conductor 91 constituting the first layer 101 is positioned relative to the insulator 71 in the first direction D1 by abutting against a pair of holding surfaces 78 a, 78 b of each holding groove 74. The multiple holding grooves 74 aligned in the first direction D1 are arranged at equal intervals in the first direction D1, so that the portion of the conductor 91 constituting the first layer 101 is wound around the tooth 65 at regular intervals in the first direction D1.

[0035] The plurality of holding grooves 74 aligned in the first direction D1 hold, for example, a portion of the conductor 91 that constitutes the first layer of the coil 81, at intervals that form a gap G1 between adjacent conductors 91 in the first direction D1 in that portion. In other words, the plurality of holding grooves 74 aligned in the first direction D1 are aligned at intervals that can hold the portion of the conductor 91 that constitutes the first layer 101, at intervals that form a gap G1 between adjacent conductors 91 in the first direction D1 in the first layer 101. Therefore, for example, a gap G1 is provided between adjacent conductors 91 in the first direction D1 in the first layer 101.

[0036] The second layer of each coil 81 is referred to as the second layer 102. In each coil 81, the second layer 102 is disposed on the outer periphery of the first layer 101. For example, in each coil 81, the second layer 102 is formed by conductor wires 91 disposed at positions indicated by reference numerals "12" to "21." In each coil 81, the portion of the conductor wires 91 constituting the second layer 102 is disposed so as to fit into a groove formed by the outer peripheries of conductor wires 91 adjacent to each other in the first direction D1 in the first layer 101 with a gap G1 between them. For example, the conductor wire 91 disposed at position indicated by reference numeral "12" in the second layer 102 fits into a groove formed by the conductor wire 91 disposed at position indicated by reference numeral "8" and the conductor wire 91 disposed at position indicated by reference numeral "10" in the first layer 101. The conductor 91 located at position "12" is positioned in the first direction D1 by the conductor 91 located at position "8" and the conductor 91 located at position "10." The position of the conductor 91 located at position "12" in the first direction D1 is midway in the first direction D1 between the conductor 91 located at position "8" and the conductor 91 located at position "10" that abuts the conductor 91 located at position "12." The conductors 91 located at positions "13" to "21" are also positioned in the first direction D1 by the conductors 91 that constitute the first layer 101. The portion of the conductor 91 that constitutes the second layer 102 is positioned relative to the insulator 71 in the first direction D1 by the portion of the conductor 91 that constitutes the first layer 101, and is thereby wound around the teeth 65 at regular intervals in the first direction D1 around the outer periphery of the first layer 101.

[0037] In each coil 81, the third layer 103, the fourth layer 104, and the fifth layer 105 are also arranged to fit into grooves formed by the conductor wires 91 of the layer wound immediately before, similar to the second layer 102. In the portions of the conductor wires 91 of each coil 81 constituting the third layer and subsequent layers, the portions that abut against two conductor wires 91 aligned in the first direction D1 of the layer wound immediately before are positioned in the first direction D1 by the two conductor wires 91.

[0038] 10 and 11 , the diameter of the conductor 91 can be changed depending on the specifications of the motor 50, as long as it is within a range in which the conductor 91 can be held by the holding groove 74. That is, each holding groove 74 can hold a plurality of types of conductor 91 with different diameters. Each holding groove 74 can hold a conductor 91 of a thickness that allows the outer circumferential surface of the conductor 91 placed in that holding groove 74 to abut against each of the pair of holding surfaces 78 a, 78 b of that holding groove 74. Furthermore, the conductor 91 is of a thickness that allows the portion of the conductor 91 to be wound as the second layer of the coil 81 to be placed in the groove-shaped portion formed by any two portions of the conductor 91 held in any two holding grooves 74 adjacent to each other in the first direction D1, with the portion being abutted against each of the two portions.

[0039] 10 and 11 show, using solid lines, coil 81 in which the conductor 91 constituting coil 81 is a first conductor 91A having a first diameter D11. Also, in FIGS. 10 and 11, using chain double-dashed lines, coil 81 in which the conductor 91 constituting coil 81 is a second conductor 91B having a second diameter D12 different from the first diameter D11. For example, the second diameter D12 is larger than the first diameter D11. Note that FIGS. 7 to 9 only show coil 81 constituted by conductor 91 that is the first conductor 91A.

[0040] The retaining surface 78a in each retaining groove 74 is a surface that includes a common tangent CL1 between the outer circumferential surface of the first conductive wire 91A that abuts against the retaining surface 78a when the first conductive wire 91A is wound around the tooth 65 via the insulator 71, and the outer circumferential surface of the second conductive wire 91B that abuts against the retaining surface 78a when the second conductive wire 91B is wound around the tooth 65 via the insulator 71, in the cross section of the retaining groove 74. The retaining surface 78b in each retaining groove 74 is a surface that includes a common tangent CL2 between the outer circumferential surface of the first conductive wire 91A that abuts against the retaining surface 78b when the first conductive wire 91A is wound around the tooth 65 via the insulator 71, and the outer circumferential surface of the second conductive wire 91B that abuts against the retaining surface 78b when the second conductive wire 91B is wound around the tooth 65 via the insulator 71, in the cross section of the retaining groove 74. That is, the holding surfaces 78a, 78b of each holding groove 74 are configured so that, in the cross section of each holding groove 74, the tangent to the outer surface of the first conducting wire 91A when the first conducting wire 91A is placed in the holding groove 74 is the same as the tangent to the outer surface of the second conducting wire 91B when the second conducting wire 91B is placed in the holding groove 74.

[0041] As shown in FIG. 7 , in each insulator 71, each of the first adjacent walls 72a, 72b covers at least a portion of the first surface 63 at a position offset from the coil 81 in the first direction D1 and is adjacent to the coil 81 in the first direction D1. Each of the first adjacent walls 72a, 72b faces the coil 81 in the first direction D1. For example, each insulator 71 has the first adjacent walls 72a, 72b on both sides of the tooth 65 in a direction perpendicular to the first direction D1 as viewed from the axial direction A1. For example, in each insulator 71, the tooth covering portion 76 is located between the first adjacent walls 72a and 72b in the circumferential direction C1. In each insulator 71, the first adjacent walls 72a, 72b extend, for example, from a base end of the tooth covering portion 76, i.e., from an end of the tooth covering portion 76 in the first direction D1, to both sides in the circumferential direction C1. When the insulator 71 is attached to the tooth 65, the first adjacent walls 72a and 72b cover the first surface 63 on both sides of the tooth 65 in the circumferential direction C1.

[0042] In each insulator 71, each of the second adjacent walls 73a, 73b is adjacent to the coil 81 in the second direction D2 at a position shifted from the coil 81 in the second direction D2. Each of the second adjacent walls 73a, 73b faces the coil 81 in the second direction D2. Each insulator 71 has, for example, the second adjacent walls 73a, 73b on both sides of the tooth 65 in a direction perpendicular to the first direction D1 when viewed from the axial direction A1. In each insulator 71, for example, the tooth covering portion 76 is located between the second adjacent walls 73a and 73b in the circumferential direction C1. In each insulator 71, the second adjacent walls 73a, 73b protrude, for example, from a tip region of the tooth covering portion 76, i.e., from an end region of the tooth covering portion 76 in the second direction D2, to both sides in the circumferential direction C1. When the insulator 71 is attached to the tooth 65, the second adjacent walls 73a, 73b are located, for example, on both sides of the tooth 65 in the circumferential direction C1 and between the circumferential protrusion 67 and the coil 81 in the second direction D2.

[0043] The second adjacent wall 73a may have a first temporary retaining groove 73c. ​​For example, the first temporary retaining groove 73c is located in a tip region of the second adjacent wall 73a in the circumferential direction C1. For example, the first temporary retaining groove 73c penetrates the second adjacent wall 73a in the axial direction A1. Also, for example, the first temporary retaining groove 73c opens on the opposite side of the second adjacent wall 73b in the circumferential direction C1. Also, the second adjacent wall 73b may have a second temporary retaining groove 73d. For example, the second temporary retaining groove 73d is located in a tip region of the second adjacent wall 73b in the circumferential direction C1. For example, the second temporary retaining groove 73d penetrates the second adjacent wall 73b in the axial direction A1. Also, for example, the second temporary retaining groove 73d opens on the opposite side of the second adjacent wall 73a in the circumferential direction C1.

[0044] When the first terminal wire 82 is placed in the first temporary holding groove 73c so as to penetrate the first temporary holding groove 73c in the axial direction A1, the first terminal wire 82 can be temporarily held by the insulator 71. When the second terminal wire 83 is placed in the second temporary holding groove 73d so as to penetrate the second temporary holding groove 73d in the axial direction A1, the second terminal wire 83 can be temporarily held by the insulator 71. Note that the yoke end surface covering portion 77 may have the first temporary holding groove 73c and the second temporary holding groove 73d.

[0045] In each insulator 71, the plurality of restriction protrusions 75 protrude from at least one of the first adjacent walls 72a, 72b and the second adjacent walls 73a, 73b in a direction toward the coil 81. For example, a plurality of restriction protrusions 75 may protrude from each of the first adjacent walls 72a, 72b. For example, each insulator 71 may have two restriction protrusions 75 protruding from the first adjacent wall 72a. Furthermore, for example, each insulator 71 may have two restriction protrusions 75 protruding from the first adjacent wall 72b. Furthermore, each insulator 71 may have a plurality of restriction protrusions 75 protruding from each of the second adjacent walls 73a, 73b. For example, each insulator 71 may have one restriction protrusion 75 protruding from the second adjacent wall 73a. Furthermore, for example, each insulator 71 may have one restriction protrusion 75 protruding from the second adjacent wall 73b. The two restriction protrusions 75 protruding from the first adjacent wall 72a are referred to as restriction protrusions 75a and 75b. The two restriction protrusions 75 protruding from the first adjacent wall 72b are referred to as restriction protrusions 75c and 75d. The one restriction protrusion 75 protruding from the second adjacent wall 73a is referred to as restriction protrusion 75e. The one restriction protrusion 75 protruding from the second adjacent wall 73b is referred to as restriction protrusion 75f. The restriction protrusions 75a to 75d of each insulator 71 protrude from the first adjacent walls 72a and 72b in the first direction D1. The restriction protrusions 75e and 75f of each insulator 71 protrude from the second adjacent walls 73a and 73b in the second direction D2.

[0046] 7 to 9, each of the restricting protrusions 75a to 75f has a contact surface 75X that contacts one of both end portions in the first direction D1 of a portion of the conducting wire 91 that constitutes three or more odd layers of the coil 81. For example, each of the restricting protrusions 75a to 75f has the contact surface 75X at the tip in the protruding direction. When viewed from the axial direction A1, the contact surface 75X of each of the restricting protrusions 75a to 75f is inclined so that, of both ends of the contact surface 75X in the direction perpendicular to the first direction D1, an end 75Xb farther from the tooth 65 is farther from the coil 81 in the first direction D1 than an end 75Xa closer to the tooth 65. Therefore, for example, when viewed from the axial direction A1, the protruding height of each of the restricting protrusions 75a to 75f increases as it approaches the tooth 65 in the direction perpendicular to the first direction D1. Furthermore, the contact surface 75X of each of the restriction protrusions 75a to 75f is inclined with respect to a direction perpendicular to the first direction D1 when viewed from the axial direction A1. The direction perpendicular to the first direction D1 when viewed from the axial direction A1 is defined as a third direction D3. The third direction D3 is a direction perpendicular to the first direction D1 and perpendicular to the axial direction A1.

[0047] Each of the restriction protrusions 75a to 75f extends, for example, along the axial direction A1. Each of the restriction protrusions 75a to 75f has, for example, a triangular shape when viewed from the axial direction A1. The contact surface 75X of each of the restriction protrusions 75a to 75f has, for example, a flat surface parallel to the axial direction A1.

[0048] In each coil 81, the third layer 103 has third layer end portions 3a, 3b, 3c, and 3d at both ends of the third layer 103 in the first direction D1. The third layer end portions 3a to 3d extend, for example, along the axial direction A1 on both sides of the tooth 65 in the third direction D3. The third layer end portions 3a and 3b are disposed between the first adjacent wall 72a and the second adjacent wall 73a. The third layer end portion 3a is the conductor 91 disposed at the position indicated by the reference numeral "32." The third layer end portion 3b is the conductor 91 disposed at the position indicated by the reference numeral "22." The third layer end portions 3c and 3d are disposed between the first adjacent wall 72b and the second adjacent wall 73b. The third layer end portion 3c is the conductor 91 disposed at the position indicated by the reference numeral "33." The third layer end portion 3d is the conductor 91 disposed at the position indicated by the reference numeral "23."

[0049] The contact surface 75X of the restricting protrusion 75a contacts the third layer end portion 3a. The third layer end portion 3a contacts both the contact surface 75X of the restricting protrusion 75a and the conductor 91 located at the position indicated by reference numeral "12." The contact surface 75X of the restricting protrusion 75a prevents the third layer end portion 3a from moving in the first direction D1 relative to the insulator 71. The conductor 91 located at the position indicated by reference numeral "12" prevents the third layer end portion 3a from moving in the direction opposite to the first direction D1, i.e., the second direction D2, relative to the insulator 71. Therefore, the third layer end portion 3a is positioned in the first direction D1 by the contact surface 75X of the restricting protrusion 75a and the conductor 91 located at the position indicated by reference numeral "12."

[0050] The contact surface 75X of the restricting protrusion 75e contacts the third layer end portion 3b. The third layer end portion 3b contacts both the contact surface 75X of the restricting protrusion 75e and the conductor 91 located at the position indicated by reference numeral "20." The contact surface 75X of the restricting protrusion 75e restricts the third layer end portion 3b from moving in the second direction D2 relative to the insulator 71. The conductor 91 located at the position indicated by reference numeral "20" prevents the third layer end portion 3b from moving in the first direction D1 relative to the insulator 71. Therefore, the third layer end portion 3b is positioned in the first direction D1 by the contact surface 75X of the restricting protrusion 75e and the conductor 91 located at the position indicated by reference numeral "20."

[0051] The contact surface 75X of the restricting protrusion 75c contacts the third-layer end portion 3c. The third-layer end portion 3c contacts both the contact surface 75X of the restricting protrusion 75c and the conductor 91 located at the position indicated by reference numeral "13." Similar to the third-layer end portion 3a, the third-layer end portion 3c is positioned in the first direction D1 by the contact surface 75X of the restricting protrusion 75c and the conductor 91 located at the position indicated by reference numeral "13."

[0052] The contact surface 75X of the restricting protrusion 75f contacts the third-layer end portion 3d. The third-layer end portion 3d contacts both the contact surface 75X of the restricting protrusion 75c and the conductor 91 located at the position indicated by reference numeral "21." Similar to the third-layer end portion 3b, the third-layer end portion 3d is positioned in the first direction D1 by the contact surface 75X of the restricting protrusion 75f and the conductor 91 located at the position indicated by reference numeral "21."

[0053] In each coil 81, the fifth layer 105 has fifth-layer end portions 5a, 5b, which are one of the ends of the fifth layer 105 in the first direction D1. The fifth-layer end portions 5a, 5b extend, for example, along the axial direction A1 on both sides of the tooth 65 in the third direction D3. The fifth-layer end portion 5a is disposed between the first adjacent wall 72a and the second adjacent wall 73a. The fifth-layer end portion 5a is the conductor 91 disposed at the position indicated by the reference numeral "48." The fifth-layer end portion 5b is disposed between the first adjacent wall 72b and the second adjacent wall 73b. The fifth-layer end portion 5b is the conductor 91 disposed at the position indicated by the reference numeral "49."

[0054] The contact surface 75X of the restricting protrusion 75b contacts the fifth-layer end portion 5a. The fifth-layer end portion 5a contacts both the contact surface 75X of the restricting protrusion 75b and the conductive wire 91 located at the position indicated by reference numeral "34." Similar to the third-layer end portion 3a, the fifth-layer end portion 5a is positioned in the first direction D1 by the contact surface 75X of the restricting protrusion 75b and the conductive wire 91 located at the position indicated by reference numeral "34."

[0055] The contact surface 75X of the restricting protrusion 75d contacts the fifth-layer end portion 5b. The fifth-layer end portion 5b contacts both the contact surface 75X of the restricting protrusion 75d and the conductive wire 91 located at the position indicated by reference numeral "35." Similar to the third-layer end portion 3a, the fifth-layer end portion 5b is positioned in the first direction D1 by the contact surface 75X of the restricting protrusion 75d and the conductive wire 91 located at the position indicated by reference numeral "35."

[0056] 7, 10, and 11, for example, the abutment surface 75X of each of the restricting protrusions 75a to 75f is a plane that includes a common tangent CL3 between the outer circumferential surface of the first conducting wire 91A that abuts against the abutment surface 75X when the first conducting wire 91A is wound around the tooth 65 via the insulator 71, and the outer circumferential surface of the second conducting wire 91B that abuts against the abutment surface 75X when the second conducting wire 91B is wound around the tooth 65 via the insulator 71. That is, the inclination angle of each abutment surface 75X with respect to the third direction D3 is set so that the abutment surface 75X is a plane that includes both the tangent to the outer circumferential surface of the first conducting wire 91A when the first conducting wire 91A is wound around the tooth 65, and the tangent to the outer circumferential surface of the second conducting wire 91B when the second conducting wire 91B is disposed in the holding groove 74 on the tooth 65, when viewed in the axial direction A1.

[0057] For example, when viewed from the axial direction A1, the center O1 of the cross section of the first conducting wire 91A that abuts against the abutment surface 75X of the restricting protrusion 75a when the first conducting wire 91A is wound around the tooth 65 and the center O2 of the cross section of the second conducting wire 91B that abuts against the abutment surface 75X of the restricting protrusion 75a when the second conducting wire 91B is wound around the tooth 65 are positioned on a single straight line L11 that is perpendicular to the first direction D1. Similarly, when viewed from the axial direction A1, the center O1 of the first conducting wire 91A and the center O2 of the second conducting wire 91B that abuts against the abutment surface 75X of each of the restricting protrusions 75b to 75f are positioned on a single straight line that is perpendicular to the first direction D1. Furthermore, as long as the conductor 91 has a diameter that can be held by the retaining groove 74, the center of the cross section of each conductor 91 abutting against the restricting protrusions 75a to 75d will be located on, for example, a straight line L11 when viewed in the axial direction A1, even if the diameter of the conductor 91 is changed. Similarly, as long as the conductor 91 has a diameter that can be held by the retaining groove 74, the center of the cross section of each conductor 91 abutting against the restricting protrusions 75e, 75f will be located on, for example, a single straight line L12 when viewed in the axial direction A1, even if the diameter of the conductor 91 is changed. Therefore, for example, in each coil 81, the centers of the cross sections of the conductors 91 aligned in the third direction D3 on both sides of the tooth 65 in the third direction D3 will be at the same position in the first direction D1, that is, will be located on the same straight line perpendicular to the first direction D1. For example, the centers of the cross sections of the conductors 91 arranged at positions with reference numbers "34," "12," "13," and "35" in the third direction D3 are located on the straight line L13 when viewed from the axial direction A1. Also, for example, the centers of the cross sections of the conductors 91 arranged at positions with reference numbers "46," "30," "8," "9," "31," and "47" in the third direction D3 are located on the straight line L14 when viewed from the axial direction A1.

[0058] 7 and 10 , in each of the first adjacent walls 72a, 72b, the abutment surface 75X of the regulating protrusion 75 that is farther from the tooth 65 along the third direction D3 as viewed from the axial direction A1 may have a longer length in the third direction D3. For example, the regulating protrusion 75b protruding from the first adjacent wall 72a is farther from the tooth 65 along the third direction D3 as viewed from the axial direction A1 than the regulating protrusion 75a also protruding from the first adjacent wall 72a. The length X2 of the abutment surface 75X of the regulating protrusion 75b in the third direction D3 may be longer than the length X1 of the abutment surface 75X of the regulating protrusion 75a in the third direction D3.

[0059] When the conductor 91 having a diameter sufficient for the retaining grooves 74 to be retained is wound around the teeth 65 via the insulators 71, the abutment surface 75X of each restricting protrusion 75 abuts against the end of the three or more odd-numbered layers of the coil 81 in the first direction D1. When each layer of the coil 81 is configured such that the conductor 91 is wound around the teeth 65 in the first direction D1 at regular intervals from one end of the layer to the other in the first direction D1, the abutment surface 75X of each restricting protrusion 75 abuts against the end of the three or more odd-numbered layers of the coil 81 in the first direction D1. In such a case, the inclination angle of the abutment surface 75X with respect to the third direction D3 when viewed from the axial direction A1, the length of the abutment surface 75X in the third direction D3, and the position of the abutment surface 75X in the third direction D3 are set so that the abutment surface 75X of each restricting protrusion 75 abuts against the end of the three or more odd-numbered layers of the coil 81 in the first direction D1. Therefore, when the ends of the coil 81 in the first direction D1 in each of the three or more odd layers are abutting against the abutment surface 75X, in every layer of the coil 81, the conductor 91 is wound in the first direction D1 at a constant pitch from one end of the layer in the first direction D1 to the other end of the layer in the first direction D1.

[0060] 8 and 9, the tip 75Xc of each of the restriction protrusions 75a to 75f that protrudes the most in the protruding direction may be rounded. Although not shown in FIGS. 8 and 9, the restriction protrusions 75c, 75d, and 75f have the same tip 75Xc as the restriction protrusions 75a, 75b, and 75e. For example, the tip 75Xc of each of the restriction protrusions 75a to 75f is curved in an arc shape that is convex in the protruding direction when viewed from the axial direction A1.

[0061] (Effects of the embodiment) The effects of this embodiment will be described. (1) The stator 51 includes a stator core 61 having a first surface 63 extending along a reference axis L1, an annular portion 66 having an annular shape centered on the reference axis L1, and a plurality of teeth 65 extending from the first surface 63 in a direction perpendicular to the reference axis L1. The stator 51 also includes a plurality of insulators 71 attached to the teeth 65, respectively, and a plurality of coils 81 formed by winding a conducting wire 91 in three or more layers around the teeth 65 via the insulators 71. Each of the insulators 71 covers at least a portion of the first surface 63 at a position shifted from the coil 81 in a first direction D1 from the tip to the base end of the tooth 65, and has first adjacent walls 72a, 72b adjacent to the coil 81 in the first direction D1. Each insulator 71 also has second adjacent walls 73a, 73b adjacent to the coil 81 in the second direction D2 at positions shifted from the coil 81 in the second direction D2, which is from the base end toward the tip end of the tooth 65. Each insulator 71 also has a plurality of retaining grooves 74 that extend along the winding direction C2 of the coil 81 around the tooth 65 and in which portions of the conducting wire 91 that form the first layer of the coil 81 are disposed. Each insulator 71 also has a plurality of restricting protrusions 75 that protrude from at least one of the first adjacent walls 72a, 72b and the second adjacent walls 73a, 73b in a direction approaching the coil 81. The retaining grooves 74 are aligned at equal intervals in the first direction D1. Each of the retaining grooves 74 has a pair of retaining surfaces 78a, 78b at both ends in the first direction D1. The retaining surfaces 78a, 78b are inclined relative to the first direction D1 so that the distance between the retaining surfaces 78a, 78b in the first direction D1 increases as the retaining grooves 74 approach the openings 78d along a direction from a bottom 78c of the retaining groove 74 toward the openings 78d. The pair of retaining surfaces 78a, 78b each contact the outer peripheral surface of the conductive wire 91 disposed in the retaining groove 74. Each of the restricting projections 75 has an abutment surface 75X that abuts against an end of the coil 81 in the first direction D1 in an odd-numbered layer (three or more). When viewed along the reference axis L1, i.e., the axial direction A1, the abutment surface 75X is inclined such that an end 75Xb farther from the teeth 65 is farther from the coil 81 in the first direction D1 than an end 75Xa closer to the teeth 65.

[0062] According to this configuration, the pair of holding surfaces 78a, 78b of each holding groove 74 are inclined with respect to the first direction D1 such that the distance between them in the first direction D1 increases the closer they are to the opening 78d along the direction from the bottom 78c of the holding groove 74 toward the opening 78d. Therefore, even if the diameter of the conductor 91 is changed, as long as the conductor 91 can be placed in contact with both the pair of holding surfaces 78a and 78b, the portion of the conductor 91 that forms the first layer of the coil 81 can be positioned in the first direction D1 by the holding groove 74.

[0063] Furthermore, the portions of the conductor 91 constituting the first layer of the coil 81 are arranged in the retaining grooves 74 that are arranged at equal intervals in the first direction D1, and are thereby wound around the teeth 65 at regular intervals in the first direction D1. The portions of the conductor 91 constituting the second layer of the coil 81 can be wound around the teeth 65 so as to fit into groove-shaped portions formed by the outer surfaces of the conductor 91 that are adjacent in the first direction D1 in the first layer of the coil 81. Therefore, the portions of the conductor 91 constituting the second layer of the coil 81 are wound around the teeth 65 at regular intervals in the first direction D1. Similarly, the portions of the conductor 91 constituting the third and subsequent layers of the coil 81 are positioned in the first direction D1 by the portions of the conductor 91 that constitute the previously wound layers, and are thereby wound around the teeth 65 at regular intervals in the first direction D1.

[0064] Generally, when the number of turns of the coil 81 is the same, the larger the diameter of the conductor 91, the farther the second and subsequent layers of the coil 81 are positioned from the outer circumferential surfaces of the teeth 65 as viewed from the first direction D1. Furthermore, generally, when the number of turns of the coil 81 is the same, the larger the diameter of the conductor 91, the farther the ends of each layer of the coil 81 in the first direction D1 are from the center of the coil 81 in the first direction D1. The abutment surface 75X of each of the restricting protrusions 75 is inclined as viewed from the axial direction A1 so that, of the ends of the abutment surface 75X in the direction perpendicular to the first direction D1, an end 75Xb farther from the tooth 65 is farther from the coil 81 in the first direction D1 than an end 75Xa closer to the tooth 65. That is, when viewed from the axial direction A1, the abutment surface 75X is inclined such that the distance in the first direction D1 between the abutment surface 75X and the center of the coil 81 in the first direction D1 increases as the abutment surface 75X becomes farther from the tooth 65 in a direction perpendicular to the first direction D1. Therefore, even if the diameter of the conductor 91 is changed, the coil 81 can be wound around the tooth 65 with the same number of turns without changing the insulator 71. Furthermore, even if the diameter of the conductor 91 is changed, the abutment surface 75X of each of the restricting protrusions 75 can abut against the end in the first direction D1 of the portion of the conductor 91 that constitutes three or more odd layers of the coil 81.

[0065] For example, when a conventional insulator without the restricting protrusion 75 is used, depending on the diameter of the conductor, a gap may form between the insulator and the end of the odd-numbered layer of the coil 81 in the first direction D1. In contrast, the insulator 71 of the present embodiment has the restricting protrusion 75, which prevents a gap from forming between the insulator 71 and the end of the odd-numbered layer of the coil 81 in the first direction D1. Furthermore, the abutment surface 75X abuts against the end of the portion of the conductor 91 that constitutes three or more odd layers of the coil 81 in the first direction D1, thereby preventing the end from moving away from the center of the coil 81 in the first direction D1. In other words, even if the diameter of the conductor 91 is changed, the coil 81 can be prevented from collapsing.

[0066] For these reasons, even if the diameter of the conductor 91 that constitutes the coil 81 is changed, the portion of the conductor 91 that constitutes the first layer of the coil 81 can be wound at constant intervals in the first direction D1. Furthermore, even if the diameter of the conductor 91 that constitutes the coil 81 is changed, the restricting protrusion 75 having the abutment surface 75X prevents the third and subsequent layers of the coil 81 from collapsing. Therefore, even if the diameter of the conductor 91 is changed, the design of the insulator 71 does not need to be changed. Therefore, it is possible to reduce the variations in the insulator 71 while preventing the coil 81 from collapsing even if the diameter of the conductor 91 that constitutes the coil 81 is changed.

[0067] (2) When viewed from the axial direction A1, each abutment surface 75X of the regulating protrusion 75 is a plane that includes a common tangent CL3 between the outer surface of the first conducting wire 91A that abuts against the abutment surface 75X when the first conducting wire 91A is wound around the tooth 65 via the insulator 71, and the outer surface of the second conducting wire 91B that abuts against the abutment surface 75X when the second conducting wire 91B having a diameter (second diameter D12) different from that of the first conducting wire 91A is wound around the tooth 65 via the insulator 71.

[0068] With this configuration, whether the conducting wire 91 constituting the coil 81 is the first conducting wire 91A or the second conducting wire 91B, the end portion of the conducting wire 91 in the first direction D1 of the portion constituting the odd-numbered layers of the coil 81 can abut against the abutment surface 75X. Furthermore, regardless of the diameter of the conducting wire 91 constituting the coil 81, which has any value between the first diameter D11 of the first conducting wire 91A and the second diameter D12 of the second conducting wire 91B, the end portion of the conducting wire 91 in the first direction D1 of the portion constituting the odd-numbered layers of the coil 81 can abut against the abutment surface 75X.

[0069] (3) A pair of retaining surfaces 78a, 78b in each retaining groove 74 are surfaces that include common tangents CL1, CL2 between the outer peripheral surface of the first conducting wire 91A that abuts against the retaining surfaces 78a, 78b when the first conducting wire 91A is wound around the tooth 65 via the insulator 71, and the outer peripheral surface of the second conducting wire 91B that abuts against the retaining surfaces 78a, 78b when the second conducting wire 91B having a diameter (second diameter D12) different from that of the first conducting wire 91A is wound around the tooth 65 via the insulator 71, in a cross-section of the retaining groove 74.

[0070] With this configuration, whether the conducting wire 91 constituting the coil 81 is the first conducting wire 91A or the second conducting wire 91B, the holding groove 74 can position the conducting wire 91 arranged in the holding groove 74 in the first direction D1 by the pair of holding surfaces 78a, 78b. Furthermore, regardless of the diameter of the conducting wire 91 constituting the coil 81, which has any value between the first diameter D11 of the first conducting wire 91A and the second diameter D12 of the second conducting wire 91B, the holding groove 74 can position the conducting wire 91 arranged in the holding groove 74 in the first direction D1 by the pair of holding surfaces 78a, 78b.

[0071] (4) The insulator 71 has first adjacent walls 72a, 72b on both sides of the tooth 65 in a direction perpendicular to the first direction D1 as viewed from the axial direction A1. A plurality of restricting protrusions 75 protrude from each of the first adjacent walls 72a, 72b. The abutment surfaces 75X of the restricting protrusions 75 that are farther from the tooth 65 in the direction perpendicular to the first direction D1 as viewed from the axial direction A1 have longer lengths in the direction perpendicular to the first direction D1.

[0072] Here, two types of coils 81 each made of conductive wires 91 with different diameters are compared. When comparing the positions of the same layer in the two types of coils 81 in the direction perpendicular to the first direction D1, i.e., the third direction D3, as viewed from the axial direction A1, the closer the layer is to the outside of the coil 81, the greater the misalignment in the third direction D3 as viewed from the axial direction A1. Therefore, if the length of the abutment surface 75X in the third direction D3 is as long as the abutment surface 75X of the regulating protrusion 75 farthest from the tooth 65 along the third direction D3 as viewed from the axial direction A1, the end of the odd-numbered layer close to the outside of the coil 81 in the first direction D1 is likely to be positioned so as to overlap the abutment surface 75X in the first direction D1. Furthermore, when comparing the positions of the same layer in the two types of coils 81 in the third direction D3 as viewed from the axial direction A1, the closer the layer is to the inside of the coil 81, the smaller the misalignment in the third direction D3 as viewed from the axial direction A1. Therefore, even if the length of the abutment surface 75X in the third direction D3 is as short as the abutment surface 75X of the regulating protrusion 75 that is closer to the tooth 65 along the third direction D3 as viewed from the axial direction A1, the end portion in the first direction D1 of the odd-numbered layer that is closer to the inside of the coil 81 is likely to be positioned so as to overlap the abutment surface 75X in the first direction D1. Therefore, with this configuration, the abutment surface 75X of the regulating protrusion 75 can easily be brought into contact with the end portion in the first direction D1 of any of the three or more odd-numbered layers of the coil 81.

[0073] (5) The tip 75Xc of each of the restricting protrusions 75, which protrudes the most in the protruding direction, is rounded. With this configuration, even if the conductor 91 comes into contact with the tip 75Xc when winding the conductor 91 around the tooth 65 via the insulator 71, damage to the conductor 91 can be suppressed.

[0074] (6) The multiple retaining grooves 74 aligned in the first direction D1 hold the portions of the conductor 91 that form the first layer of the coil 81 at intervals that form a gap G1 between adjacent conductors 91 in the first direction D1.

[0075] With this configuration, in the first layer of the coil 81, contact between adjacent conductive wires 91 in the first direction D1 can be prevented. Furthermore, in the second and subsequent layers of the coil 81, the conductive wires 91 are wound at the same intervals in the first direction D1 as in the first layer. Therefore, in the second and subsequent layers of the coil 81, gaps are formed between adjacent conductive wires 91 in the first direction D1, so that contact between adjacent conductive wires 91 in the first direction D1 can be prevented. This prevents the conductive wires 91 from being damaged by contact between adjacent portions of the conductive wires 91 in the first direction D1.

[0076] (7) Each of the retaining grooves 74 has a V-shape in cross section. According to this configuration, the retaining groove 74 has a simple shape. Therefore, the shape of the insulator 71 is prevented from becoming complicated by the retaining groove 74. Furthermore, the retaining groove 74 having a simple shape makes it easy to position the portion of the conductor 91 that forms the first layer of the coil 81 in the conductor 91 in the first direction D1 for multiple types of conductor 91 with different diameters.

[0077] (Example of change) This embodiment can be modified as follows: This embodiment and the following modifications can be combined and implemented within the scope of technical compatibility.

[0078] As shown in FIG. 12 , the stator 51 may include an insulator 71A instead of the insulator 71 of the above embodiment. The insulator 71A has a restricting protrusion 75A instead of the restricting protrusion 75 of the above embodiment. Note that in FIG. 12 , the same reference numerals are used for components that are the same as or correspond to those of the above embodiment. The restricting protrusion 75A is elastically deformable so that the contact surface 75X moves away from the coil 81 along the first direction D1. Furthermore, the restricting protrusion 75A presses the conductor 91 contacting the contact surface 75X toward the center of the coil 81 in the first direction D1. For example, the third layer end 3a located at the position indicated by reference numeral "32" is pressed in the second direction D2 by the restricting protrusion 75A, thereby being pressed against the conductor 91 located at the position indicated by reference numeral "34" and the conductor 91 located at the position indicated by reference numeral "12."

[0079] This makes it possible to more stabilize the positions of the ends of the odd-numbered layers of the coil 81 in the first direction D1, thereby further preventing the coil 81 from collapsing. The insulator 71A may have the restricting protrusion 75 of the above embodiment and at least one restricting protrusion 75A.

[0080] As shown in FIG. 13 , the stator 51 may include an insulator 71B instead of the insulator 71 of the above embodiment. The insulator 71B includes a first member 111 having a restricting protrusion 75 and a second member 112 that is formed separately from the first member 111 and to which the first member 111 is fixed. The first member 111 and the second member 112 may be made of the same material or different materials. The first member 111 may be fixed to the second member 112 by, for example, snap fitting. Furthermore, the first member 111 may be fixed to the second member 112 by, for example, any method such as adhesive bonding, press fitting, welding, or pasting.

[0081] In this way, the shape of the first member 111 can be changed without changing the shape of the second member 112. Therefore, for example, the number of restricting protrusions 75, the shape of the restricting protrusions 75, or the position of the restricting protrusions 75 can be changed without changing the shape of the second member 112. This makes it possible to use more types of conductors 91 with different diameters. Furthermore, the shape of the second member 112 can be changed without changing the shape of the first member 111. Therefore, by combining multiple types of first members 111 and second members 112, it becomes possible to accommodate multiple variations of the insulator 71 using fewer types of first members 111 and second members 112 than the number of variations of the insulator 71.

[0082] The multiple retaining grooves 74 aligned in the first direction D1 may, for example, hold the portion of the conductor 91 that constitutes the first layer of the coil 81 at an interval such that no gap G1 is formed between adjacent conductors 91 in the first direction D1 in that portion.

[0083] The tip 75Xc of each of the restriction protrusions 75a to 75f does not have to be rounded. In the above embodiment, in each of the first adjacent walls 72a, 72b, the length of the abutment surface 75X in the third direction D3 increases as the restriction protrusion 75 is farther from the tooth 65 along the third direction D3 as viewed from the axial direction A1. However, the length of the abutment surface 75X in the third direction D3 may be the same for all of the restriction protrusions 75, for example. Furthermore, the length of the abutment surface 75X in the third direction D3 is not limited to this, and may be set to any length for each restriction protrusion 75.

[0084] The number of restricting protrusions 75 may be changed as appropriate. The insulator 71 only needs to have at least one restricting protrusion 75 protruding from at least one of the first adjacent walls 72a, 72b and the second adjacent walls 73a, 73b. Even in this case, the coils 81 can be prevented from collapsing at the ends in the first direction D1 of the odd-numbered layers of the coils 81 that are in contact with the contact surfaces 75X of the restricting protrusions 75.

[0085] The holding groove 74 may be provided only in the side surface covering portions 76b and 76c. Also, the holding groove 74 may be provided only in the end surface covering portion 76a. The shape of the insulator 71 is not limited to that of the above embodiment. However, the insulator 71 has first adjacent walls 72a, 72b, second adjacent walls 73a, 73b, multiple holding grooves 74, and multiple restricting protrusions 75. For example, the insulator 71 may have first temporary holding grooves 73c and second temporary holding grooves 73d in the yoke end surface covering portion 77. In this case, the first temporary holding grooves 73c and second temporary holding grooves 73d are, for example, groove-shaped grooves that penetrate the yoke end surface covering portion 77 in the first direction D1 and open to one side in the axial direction A1.

[0086] The shape and configuration of the stator core 61 may be changed as appropriate. For example, the number of split cores 62 included in the stator core 61 is not limited to 12, and may be any plural number. The stator core 61 may not be split in the circumferential direction C1. The stator core 61 may have an annular portion 66 and a plurality of teeth 65 extending outward from the annular portion 66.

[0087] The technical ideas that can be understood from the above-described embodiment and modified examples will be described. (i) A stator as described in claim 1 or claim 2, wherein the pair of retaining surfaces in each of the retaining grooves are surfaces that include a common tangent (CL1, CL2) between the outer peripheral surface of the first conductor (91A), which is the conductor, that abuts against the retaining surface when the first conductor (91A) is wound around the tooth via the insulator, and the outer peripheral surface of the second conductor (91B), which is the conductor and has a diameter different from that of the first conductor, that abuts against the retaining surface when the second conductor (91B) is wound around the tooth via the insulator.

[0088] (ii) A stator as described in any one of claims 1, 2, and (i), wherein the insulator has a first adjacent wall on each side of the tooth in a direction perpendicular to the first direction when viewed from a direction along the reference axis, and a plurality of regulating protrusions protrude from each of the first adjacent walls, and the abutment surface of the regulating protrusion that is farther from the tooth along the direction perpendicular to the first direction when viewed from a direction along the reference axis has a longer length in the direction perpendicular to the first direction.

[0089] (C) A stator according to any one of claims 1, 2, (A) and (B), wherein a tip (75Xc) of each of the restricting projections that protrudes most in the protruding direction is rounded.

[0090] (ii) A stator as described in any one of claims 1, 2, and (i) to (iii), wherein the plurality of retaining grooves aligned in the first direction hold the portion of the conductor that constitutes the first layer of the coil at an interval such that a gap (G1) is formed between adjacent conductors in the first direction in that portion.

[0091] (e) A stator according to claim 1, claim 2, and any one of (a) to (d), wherein each of the holding grooves has a V-shape in cross section. (F) A stator as described in claim 1, claim 2, and any one of (A) to (E), wherein at least one of the regulating protrusions is elastically deformable so that the abutment surface moves away from the coil along the first direction, and pushes the conductor abutting the abutment surface toward the center of the coil in the first direction.

[0092] (G) A stator as described in any one of claims 1, 2, and (I) to (F), wherein the insulator has a first member (111) having the regulating protrusion, and a second member (112) formed separately from the first member and to which the first member is fixed.

[0093] The above description is merely illustrative. Those skilled in the art will recognize that many more possible combinations and permutations are possible other than the components and methods (manufacturing processes) listed for the purpose of illustrating the technology of the present disclosure. The present disclosure is intended to embrace all alternatives, modifications, and variations that fall within the scope of the present disclosure, including the claims and appendices. [Explanation of symbols]

[0094] 51 stator, 61 stator core, 63 first surface, 65 teeth, 66 annular portion, 71, 71A, 71B insulator, 72a, 72b first adjacent wall, 73a, 73b second adjacent wall, 74, 74a to 74l retaining groove, 75, 75a to 75f, 75A restricting protrusion, 75X abutting surface, 75Xa, 75Xb end, 75Xc tip, 78a, 78b retaining surface, 78c bottom, 78d opening, 81 coil, 91 conductor, 91A first conductor, 91B second conductor, 111 first member, 112 second member, C2 winding direction, CL1, CL2 common tangent, CL3 common tangent, D1 first direction, D2 second direction, G1 gap, L1 reference axis

Claims

1. a stator core (61) having a first surface (63) extending along a reference axis (L1), an annular portion (66) having an annular shape centered on the reference axis, and a plurality of teeth (65) extending from the first surface in a direction perpendicular to the reference axis; a plurality of insulators (71, 71A, 71B) attached to the teeth, respectively; a plurality of coils (81) each formed by winding a conducting wire (91) around the teeth in three or more layers via the insulator; Equipped with Each of the insulators has a first adjacent wall (72a, 72b) that covers at least a portion of the first surface at a position shifted from the coil in a first direction (D1) from the tip end toward the base end of the tooth and that is adjacent to the coil in the first direction, a second adjacent wall (73a, 73b) that is shifted from the coil in a second direction (D2) from the base end toward the tip end of the tooth and that is adjacent to the coil in the second direction, a plurality of holding grooves (74, 74a to 74l) that extend along a winding direction (C2) of the coil around the tooth and in which portions of the conductor that constitute a first layer of the coil are disposed, and a plurality of restricting protrusions (75, 75a to 75f, 75A) that protrude from at least one of the first adjacent wall and the second adjacent wall in a direction approaching the coil, The holding grooves are arranged at equal intervals in the first direction, Each of the holding grooves has a pair of holding surfaces (78a, 78b) at both ends in the first direction, the holding surfaces (78a, 78b) being inclined with respect to the first direction so that the distance therebetween in the first direction increases as the holding groove approaches the opening (78d) along a direction from a bottom (78c) of the holding groove toward the opening, the pair of holding surfaces contact the outer peripheral surfaces of the conductors disposed in the holding grooves, Each of the restriction projections has a contact surface (75X) that contacts an end portion of three or more odd-numbered layers of the coil in the first direction, A stator in which, when viewed from a direction along the reference axis, the abutment surface is inclined so that, of both ends of the abutment surface in a direction perpendicular to the first direction, the end (75Xb) farther from the tooth is farther from the coil in the first direction than the end (75Xa) closer to the tooth.

2. 2. The stator of claim 1, wherein the abutment surface of each of the regulating protrusions is a plane that includes a common tangent (CL3) between the outer surface of the first conductor (91A) that abuts against the abutment surface when the first conductor is wound around the tooth via the insulator, and the outer surface of the second conductor (91B) that abuts against the abutment surface when the second conductor is wound around the tooth via the insulator and has a diameter different from that of the first conductor, when viewed from a direction along the reference axis.

3. 2. The stator of claim 1, wherein the pair of retaining surfaces in each of the retaining grooves are surfaces that include a common tangent (CL1, CL2) between an outer peripheral surface of a first conductor (91A) that is the conductor and abuts against the retaining surface when the first conductor is wound around the tooth via the insulator, and an outer peripheral surface of a second conductor (91B) that is the conductor and has a diameter different from that of the first conductor and abuts against the retaining surface when the second conductor is wound around the tooth via the insulator.

4. the insulator has the first adjacent walls on both sides of the tooth in a direction perpendicular to the first direction when viewed from a direction along the reference axis, A plurality of the restricting projections protrude from each of the first adjacent walls, 2. The stator of claim 1, wherein the abutment surface of the regulating protrusion that is farther from the tooth along a direction perpendicular to the first direction when viewed from a direction along the reference axis has a longer length in the direction perpendicular to the first direction.

5. 2. The stator according to claim 1, wherein a tip (75Xc) of each of said restricting projections that protrudes most in the protruding direction is rounded.

6. 2. The stator of claim 1, wherein the plurality of retaining grooves arranged in the first direction hold the portion of the conductor that constitutes the first layer of the coil at an interval such that a gap (G1) is formed between adjacent conductors in the first direction in that portion.

7. The stator of claim 1 , wherein each of the retaining grooves is V-shaped in cross section.

8. 2. The stator of claim 1, wherein at least one of the regulating protrusions is elastically deformable so that the abutment surface moves away from the coil along the first direction and pushes the conductor abutting the abutment surface toward the center of the coil in the first direction.

9. 2. The stator according to claim 1, wherein the insulator has a first member (111) having the regulating protrusion, and a second member (112) formed separately from the first member and to which the first member is fixed.

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