Insulator structure

Abstract

To provide an insulator structure capable of improving a space factor by improving adhesion of winding to teeth.SOLUTION: An insulator 38 includes: an outer peripheral piece 41; an inner peripheral piece 42 facing the outer peripheral piece 41 in a teeth axial direction Dt1; and a sidewall section 43 connecting the outer peripheral piece 41 and the inner peripheral piece 42. A space surrounded by the outer peripheral piece 41, the inner peripheral piece 42, and the sidewall section 43 is defined as a housing section 45 of winding 32. A curved section 47 is formed between the outer peripheral piece 41 and the sidewall section 43. In an inner side surface of the curved section 47 facing the housing section 45 side, there are formed a first inclined surface 48a extending obtusely from an outer surface 43a of the sidewall section 43 to an outer peripheral side of a teeth radial direction Dt2, a step surface 49 extending from a tip of the first inclined surface 48a to a side opposite to the housing section 45 along the teeth axial direction Dt1, and a second inclined surface 48b extending from a tip of the step surface 49 to an outer peripheral side of the teeth radial direction Dt2 in parallel to the first inclined surface 48a.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an insulator structure. [Background technology]

[0002] In recent years, efforts to realize a low-carbon or carbon-free society have become more active, and research and development into electrification technologies is being conducted in vehicles to reduce CO2 emissions and improve energy efficiency. For example, in rotating electrical machines such as vehicle drive motors, wound field motors are sometimes used instead of the mainstream embedded magnet type. Wound field motors place a coil on the rotor instead of a permanent magnet, and generate magnetic flux in the rotor by passing a current through this coil. Wound field motors are expected to operate highly efficiently by making it possible to adjust the amount of magnetic flux in the rotor, and by not using permanent magnets, there are no concerns about the stable supply of rare earths.

[0003] That is, at least one of the stator and rotor of the motor has a circular annular portion, a plurality of cores (teeth) protruding radially inward or outward from the annular portion, and a coil with a conducting wire wound around the outer periphery of each core. For example, Patent Document 1 discloses providing steps having a specific height on the surfaces of the teeth (specifically, the surfaces of the insulators) in order to increase the space factor of the conductor wires in the slots between the cores. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2007-135360 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the above conventional technology, flange-shaped outer and inner pieces are provided on both axial sides of the teeth, and the coil windings are stored in a stacked state between the outer and inner pieces. The outer and inner pieces have planar opposing surfaces that are perpendicular to the axial direction of the teeth facing each other in the axial direction of the teeth. However, the conductor that constitutes the windings may be curved due to its wire tendency, which may impair its adhesion to the teeth or reduce its alignment.

[0006] Therefore, an object of the present invention is to provide an insulator structure that can improve the adhesion of the windings to the teeth to improve the space factor, thereby contributing to improved energy efficiency. [Means for solving the problem]

[0007] As a means for solving the above problems, a first aspect of the present invention provides an insulator structure that is attached to each of a plurality of teeth aligned in a circumferential direction of a motor, the insulator comprising: an outer peripheral piece that is provided on one end side of the tooth in a teeth axial direction along the motor radial direction and protrudes outward when viewed from the teeth axial direction; an inner peripheral piece that is provided on the other end side of the tooth in the teeth axial direction and protrudes outward when viewed from the teeth axial direction and faces the outer peripheral piece in the teeth axial direction; and a side wall portion that covers the outer periphery of the tooth when viewed from the teeth axial direction and connects the outer peripheral piece and the inner peripheral piece, The space surrounded by the second opposing surface facing the outer periphery and the outer surface of the side wall portion is used as a storage section for the winding, and in a cross section along the teeth axial direction, a curved portion is formed between the outer peripheral piece and the side wall portion which is convex on the opposite side to the storage section, and the inner surface of the curved portion facing the storage section is formed with a first inclined surface extending from the outer surface of the side wall portion to the outer periphery in the teeth radial direction at an obtuse angle with respect to the outer surface, a step surface extending along the teeth axial direction from a tip of the first inclined surface to the opposite side of the storage section in the teeth axial direction, and a second inclined surface extending from the tip of the step surface to the outer periphery in the teeth radial direction, parallel to the first inclined surface.

[0008] According to this configuration, by forming a curved portion that forms a convex arc on the opposite side to the storage portion between the outer peripheral piece at one end in the teeth axial direction and the side wall portion along the teeth axial direction, it becomes easier to avoid stress concentration between the outer peripheral piece and the side wall portion. In a portion of the curved portion that starts to rise from the side wall portion in the teeth radial direction outward (a portion with a gentle inclination angle relative to the side wall portion), a sloped surface that partially ensures a rise angle is formed, while including a step surface along the teeth axial direction, so that the inclination angle of the rising portion relative to the side wall portion can be gently suppressed. The space in which the winding can be wound can be expanded in the teeth axial direction along the step surface. The inclination angle of the sloped surface relative to the side wall surface is set to an angle along the tangent of the teeth axial end of the windings stacked in a bale, for example. This suppresses the occurrence of dead space at the teeth axial end of the winding. In this way, by providing a shape on the side wall side of the curved portion that combines a tapered inclined surface and a step surface along the tooth axial direction, the winding space in the storage section is expanded at the rising part of the curved shape, and the number of windings can be increased. Then, by using the tension of the winding to press it against the tapered inclined surface while dropping it onto the bottom (outer surface) of the storage section, it is possible to wind the winding without any gaps in the axial direction of the teeth all the way to the outer peripheral piece, improving the adhesion of the winding and improving the space factor (the proportion of the space inside the storage section that the winding occupies).

[0009] A second aspect of the present invention is characterized in that, in the above-mentioned first aspect, the winding is composed of a conductor wire having a circular cross section and is stacked in the radial direction of the teeth to form multiple layers, and the height h from the outer surface to the step surface in the radial direction of the teeth is expressed by the following formula, where D is the maximum diameter of the conductor wire and n is the number of layers of winding wire overlapping in the radial direction of the teeth. h=D×(√3 / 2)×(n-1)+D With this configuration, a step surface can be disposed on the extension of a tangent line that contacts the multiple windings on the radially outer side of one layer of the stacked windings of the teeth. This eliminates the need for step-up and step-down processing of the windings at the step surface, reduces the dead space between the winding layers, prevents collapse of the upper layer, and ensures the alignment of the windings.

[0010] A third aspect of the present invention is the above-mentioned first or second aspect, and is characterized in that, in a cross-section along the tooth axial direction, the corner between the inclined surface and the step surface has an arc shape formed therein, the arc shape having the same diameter as the outer diameter of the circular cross-sectional conductor that constitutes the winding. According to this configuration, by providing a rounded edge with the same diameter as the conductor at the corner between the inclined surface and the step surface, an arc shape simulating the conductor is formed at the corner between the step surface and the inclined surface, making it appear as if the windings are continuously lined up. This reduces the dead space between the layers of the winding, prevents the upper layer from collapsing, and ensures the alignment of the windings.

[0011] A fourth aspect of the present invention is characterized in that, in any one of the first to third aspects described above, the distance L from the outer peripheral piece to the inner peripheral piece in the teeth axial direction is expressed by the following formula, where Nt is the number of turns of the first layer winding and D is the outer diameter of the circular cross-sectional conductor that constitutes the winding. L = D × Nt According to this configuration, by setting the distance from the outer peripheral piece to the inner peripheral piece in the tooth axial direction to an integer multiple of the outer diameter of the conductor (winding), it is possible to reduce the dead space between the layers of the winding, prevent collapse of the upper layers, and ensure alignment of the winding.

[0012] A fifth aspect of the present invention is characterized in that, in any one of the first to fourth aspects, the inclined surfaces are inclined so as to be positioned toward one side of the outer periphery in the tooth axial direction as they move radially outward of the teeth. According to this configuration, the inclined surface is inclined so that it is located on one side of the outer periphery (the opposite side to the storage section) in the tooth axial direction as it moves radially outward from the teeth, thereby widening the opening of the storage section on the radially outward side of the teeth, making it easier to wind the windings. Effect of the Invention

[0013] According to the present invention, it is possible to provide an insulator structure that can improve the adhesion of the winding to the teeth and thereby improve the space factor. [Brief description of the drawings]

[0014] [Figure 1] 1 is an exploded perspective view of a motor according to an embodiment of the present invention. [Diagram 2] 4 is a plan view showing a part of a circumferential direction of a rotor of the motor as viewed from an axial direction, including a partial cross section. FIG. [Diagram 3] 3 is an enlarged view showing a cross-sectional portion of the coil shown in FIG. 2. [Figure 4] FIG. 4 is an enlarged view of part IV in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. <Motor 1> FIG. 1 is an exploded perspective view of a motor (rotating electric machine) 1 to which an embodiment of the present invention is applied. 1, the motor 1 includes a rotor 2, a stator 3, and a casing (not shown) that covers the rotor 2 and the stator 3. In this embodiment, the rotor 2 is disposed on the inner peripheral side of the stator 3. In other words, the motor 1 is an inner rotor type motor.

[0016] The motor 1 of the embodiment is a drive motor for an electric vehicle. The motor 1 of the embodiment is a wound field motor, and has a rotor structure using a field winding (coil 37) instead of a permanent magnet. The motor 1 generates a magnetic flux in the rotor 2 by passing a direct current from an external source through the field winding, and makes the field magnetic flux adjustable.

[0017] <Rotor 2> The rotor 2 has a rotating shaft 21, a rotor core 22, a plurality of magnetic pole portions 23, and a commutator 24. The rotating shaft 21 extends in an axial direction (motor axial direction) Da. The rotating shaft 21 is supported by a casing via bearings (both not shown). The rotating shaft 21 is supported rotatably in a circumferential direction (motor circumferential direction) Dc about an axis C extending in the axial direction Da.

[0018] The rotor core 22 is provided outside (on the outer periphery side) of the rotating shaft 21 in a radial direction (motor radial direction) Dr centered on the axis C. The rotor core 22 is formed in a cylindrical shape with the axis C as its axis. When viewed from the axial direction Da, a shaft insertion hole 22a through which the rotating shaft 21 is inserted is formed in the center of the rotor core 22. The rotor core 22 is rotatable integrally with the rotating shaft 21 in the circumferential direction Dc.

[0019] The magnetic pole portions 23 are disposed at equal intervals in the circumferential direction Dc on the outer periphery of the rotor core 22. Each magnetic pole portion 23 includes a coil 37. The coil 37 is formed by winding the winding 32 via an insulator 38 around the outer periphery of a tooth 35 formed on the rotor core 22. The coil 37 and the insulator 38 will be described in detail later.

[0020] The commutator 24 is coaxially provided on one end of the rotating shaft 21. The commutator 24 is rotatable in the circumferential direction Dc integrally with the rotating shaft 21. A brush 25 supported by a casing contacts the commutator 24 in the radial direction Dr, facing the commutator 24.

[0021] <Stator 3> The stator 3 is disposed on the outer circumferential side in the radial direction Dr with a gap (air gap) therebetween with respect to the rotor core 22. The stator 3 is fixed to the inner circumferential side in the radial direction Dr of the casing. The stator 3 has a stator core and a plurality of magnetic pole portions (neither of which are shown).

[0022] <Details of Rotor 2> The rotor 2 will now be described in more detail. As shown in FIG. 2, rotor core 22 integrally includes an annular portion 34 and a plurality of teeth 35. The annular portion 34 is formed on the inner peripheral side (the rotating shaft 21 side) of the rotor core 22. The annular portion 34 extends in the circumferential direction Dc, and is formed in an annular shape when viewed from the axial direction Da.

[0023] The teeth 35 are formed at equal intervals in the circumferential direction Dc. Each tooth 35 extends from the outer periphery of the annular portion 34 toward the outer periphery along the radial direction Dr. A slot 36 is formed between adjacent teeth 35 in the circumferential direction Dc. The slot 36 is formed by cutting out the outer periphery of the rotor core 22.

[0024] The slots 36 and the teeth 35 are formed in the same number (eight in this embodiment). The rotor core 22 may be configured to be divisible in the circumferential direction Dc for each of the teeth 35. A line Ct in the figure indicates a central axis line along the central axis line of the teeth 35 (the protruding direction of the teeth 35 (the motor radial direction Dr)). Hereinafter, the protruding direction of the teeth 35 is referred to as a teeth axial direction Dt1, and the direction perpendicular to the teeth axial direction Dt1 is referred to as a teeth radial direction Dt2.

[0025] The winding 32 is a conductive wire (e.g., copper wire) and is held by the rotor core 22 in the form of a coil 37. The winding 32 is wound around each of the multiple teeth 35 via an insulator 38 made of insulating resin. When viewed from the teeth axis direction Dt1, the winding 32 is wound so that multiple layers 32a are stacked around the outer periphery of the teeth 35. By winding the winding 32 around each tooth 35, the rotor 2 is formed with multiple coils 37 arranged at intervals in the circumferential direction Dc. A slot pole (insulating plate) 39 made of insulating resin is inserted between a pair of coils 37 adjacent to each other in the circumferential direction Dc.

[0026] <Insulator 38> 2 and 3, the insulator 38 of the embodiment has a flange-shaped outer peripheral piece 41 provided at one end side (motor outer peripheral side) in the teeth axis direction Dt1, a flange-shaped inner peripheral piece 42 provided at the other end side (motor inner peripheral side) in the teeth axis direction Dt1, and a cylindrical side wall portion 43 connecting the outer peripheral piece 41 and the inner peripheral piece 42 to each other. An internal space surrounded on three sides by the opposing surfaces 41a, 42a of the outer peripheral piece 41 and the inner peripheral piece 42 and an outer surface 43a of the side wall portion 43 serves as a storage portion 45 that stores the coil 37 formed by stacking the windings 32. A pair of storage portions 45 adjacent to each other in the motor circumferential direction Dc form a slot 36.

[0027] The windings 32 are densely packed in the storage section 45. The two-dot chain line 45a in the figure is an imaginary line extending between the ends of the outer peripheral piece 41 and the inner peripheral piece 42 on the outer side in the radial direction of the teeth, and indicates the outer shape of the storage section 45 on the outer side in the radial direction of the teeth.

[0028] 2, 3 and 4 show cross sections along the teeth axis direction Dt1 (cross sections passing through the central axis Ct) of the coil 37 and the insulator 38. Hereinafter, these cross sections may be referred to as "cross sections shown in the respective figures."

[0029] 3, a curved portion 47 that is curved in an arc shape is formed at the corner between the outer peripheral piece 41 and the side wall portion 43 in the cross section shown in each figure. A plurality of (e.g., two) inclined surfaces 48a, 48b are formed on the inner peripheral side of the curved portion 47. The plurality of inclined surfaces 48a, 48b extend toward the outer side in the radial direction of the teeth at the same inclination angles θa, θb in the cross section shown in each figure. A step surface 49 that extends linearly along the teeth axis direction Dt1 is formed between the plurality of inclined surfaces 48a, 48b in the cross section shown in each figure.

[0030] The winding 32 of the layer 32a (first layer) closest to the side wall portion 43 is wound while being pressed against the outer surface 43a of the side wall portion 43 by tension during the winding operation. A distance L in the teeth axial direction Dt1 between the outer peripheral piece 41 and the inner peripheral piece 42 is set to an integer multiple of the outer diameter (diameter) D of the conductor constituting the winding 32, as described below. As a result, the winding 32 is wound while being pressed radially inward of the teeth, and the winding 32 is arranged without gaps in the teeth axial direction Dt1.

[0031] By connecting the multiple inclined surfaces 48a, 48b via the step surface 49 along the teeth axis direction Dt1, the following effect is achieved in a portion of the curved portion 47 that starts to rise from the side wall portion 43 to the outside in the teeth radial direction (a portion where the inclination angle 47c with respect to the side wall portion 43 is gentle, hereinafter referred to as the rising portion 47a). That is, by providing the step surface 49 along the teeth axis direction Dt1 between the multiple inclined surfaces 48a, 48b in the rising portion 47a of the curved portion 47, it is possible to gently reduce the inclination angle 47c of the rising portion 47a with respect to the side wall portion 43 while forming the multiple inclined surfaces 48a, 48b that partially ensure the rise angles θa, θb.

[0032] The "portion that starts to rise from the side wall portion 43 to the outside in the radial direction of the teeth" of the curved portion 47 is, for example, in the cross section shown in each drawing, a range of about half the circumference on the side wall portion 43 side of the curved portion 47. Also, the "inclination angle 47c with respect to the side wall portion 43" of the rising portion 47a is, for example, in the cross section shown in each drawing, the inclination angle of a straight line 47b that connects the end of the rising portion 47a on the side wall portion 43 side and the end on the outside in the radial direction of the teeth.

[0033] As shown in Fig. 4, the multiple inclined surfaces 48a, 48b are formed in parallel to a first tangent t1 that contacts the multiple windings 32 at one end in the teeth axis direction of the stacked windings 32. Even if the number of layers of the windings 32 is increased, each inclined surface 48a, 48b contacts the windings 32 at one end in the teeth axis direction of each layer 32a. The windings 32 at one end in the teeth axis direction of each layer 32a are arranged along each inclined surface 48a, 48b. This reduces dead space at one end in the teeth axis direction of each layer 32a.

[0034] 4, when the windings 32 having a circular cross section are stacked in a bale, a plurality of the windings 32 are stacked in an equilateral triangular shape at various points of the coil 37. In a pair of overlapping layers 32a, the distance A in the teeth radial direction Dt2 between the axial centers 32c of the windings 32 in each layer 32a is given by the following formula (1). A = √3 D / 2 = (√3 / 2) D (D is the maximum diameter (outer diameter) of the winding 32) (1)

[0035] The height T in the radial direction Dt2 of the teeth of the two-layered windings 32 stacked in a bale is T = A + D. If the number of layers increases, for example, T = 2·A+D for a three-layered winding 32, and T = 3·A+D for a four-layered winding 32. That is, the height T in the radial direction Dt2 of the teeth of the multiple-layered winding 32 is expressed by the following equation (2). T = (n-1) A + D = (n-1) (√3 / 2) D + D (n is the number of layers of the winding 32 (a natural number)) (2)

[0036] In the embodiment, the height h in the tooth radial direction Dt2 from the outer surface 43a of the side wall portion 43 to the step surface 49 is set to the height T represented by the above formula (2).

[0037] As a result, the height of the second tangent t2 that contacts one of the layers 32a of the stacked winding 32 from the outside in the radial direction of the teeth and the height T of the step surface 49 are the same height. The surface along the second tangent t2 and the step surface 49 are continuous and flush with each other. Therefore, when winding the winding 32 further outward in the radial direction of the teeth than the height T of the step surface 49, the winding 32 is wound on a surface at the same height in the radial direction Dt2 of the teeth including the step surface 49. As a result, the outer circumferential surface of the coil 37 is formed flush.

[0038] In a cross section along the teeth axis direction Dt1, the corner between the step surface 49 and the inclined surface 48a is chamfered to form an arc shape 51 having the same diameter as the outer diameter of the winding 32. As a result, a simulated winding 32 is present at the corner between the step surface 49 and the inclined surface 48a, as if the winding 32 were continuously lined up on a surface at the same height as the step surface 49. As a result, when winding 32 is wound on a surface at the same height as the step surface 49, it becomes easier to form layer 32a of winding 32 flush with the surface up to the step surface 49.

[0039] In the embodiment, the step surface 49 extends linearly along the teeth axis direction Dt1 in a cross section along the teeth axis direction Dt1, but is not limited to this configuration. For example, the step surface 49 may be formed in a wave shape having a concave shape along the outer diameter of the winding 32 in a cross section along the teeth axis direction Dt1. In this case, the adhesion of the winding 32 on the step surface 49 to the step surface 49 is improved, and the layer 32a of the winding 32 on the surface at the same height as the step surface 49 can be more easily formed flush.

[0040] As shown in FIG. 3, the distance L between the inner peripheral piece 42 and the outer peripheral piece 41 in the teeth axial direction Dt1 is expressed by the following formula (3). L = D Nt (Nt is the number of turns of the first layer winding 32 (a natural number)) (3)

[0041] As a result, when the first layer winding 32 is wound with a specified tension for a specified number of turns, the first layer winding 32 is arranged without any gaps in the teeth axis direction Dt1 between the inner peripheral piece 42 and the outer peripheral piece 41. This reduces the dead space around the first layer, improving the space factor of the winding 32.

[0042] Each inclined surface 48a, 48b is inclined so as to be located on the outer axial side of the teeth (the side from the center of the insulator 38 in the teeth axial direction toward the outer peripheral piece 41) as it approaches the outer side in the teeth radial direction. As a result, the number of turns of the winding 32 in the teeth axial direction Dt1 increases on the layer 32a located on the outer side in the teeth radial direction. Also, since the storage section 45 becomes wider in the teeth axial direction Dt1 as it approaches the outer side in the teeth radial direction, the winding 32 becomes easier to wind.

[0043] In a cross section along the teeth axis direction Dt1, the inclination angles θa, θb of the inclined surfaces 48a, 48b with respect to the outer surface 43a (teeth axis direction Dt1) of the side wall portion 43 are each set to 60 degrees (angles along the winding distribution in the bale stacking). As a result, while the dead space between the layers of the winding 32 is reduced by stacking the windings 32, the windings 32 of each layer 32a are arranged to be in contact with the inclined surfaces 48a, 48b of 60 degrees at one end of the windings 32 in the teeth axis direction, thereby reducing the dead space at one end of the windings 32 in the teeth axis direction. Therefore, the adhesion of the windings 32 can be improved and at the same time the space factor can be improved.

[0044] In the embodiment, the configuration has two inclined surfaces 48a, 48b and a single step surface 49 formed between the two inclined surfaces 48a, 48b, but is not limited to this configuration. For example, a configuration may be provided with three or more step surfaces and two or more step surfaces formed between two adjacent inclined surfaces. In this case, too, it is preferable that the inclination angles θa, θb of each inclined surface with respect to the outer surface 43a (teeth axis direction Dt1) be 60 degrees.

[0045] The opposing surface 42a of the inner peripheral piece 42 is an inclined surface that is inclined so as to be positioned more outward in the axial direction of the teeth (the side from the center of the insulator 38 in the axial direction toward the inner peripheral piece 42) as it approaches the outer side in the radial direction of the teeth. Similar to the inclined surfaces 48a, 48b of the outer peripheral piece 41, the inclined surface of the inner peripheral piece 42 is formed parallel to a tangent line that contacts the multiple windings 32 at the other end of the piled-up windings 32 in the axial direction. The inclination angle of the inclined surface of the inner peripheral piece 42 with respect to the outer surface 43a of the side wall portion 43 (the teeth axial direction Dt1) is set to 60 degrees.

[0046] As described above, the insulator structure in the above embodiment is a structure of an insulator 38 attached to each of a plurality of teeth 35 arranged in a motor circumferential direction Dc, the insulator structure includes an outer circumferential piece 41 provided on one end side of the tooth 35 in the teeth axial direction Dt1 along the motor radial direction Dr and protruding outward when viewed from the teeth axial direction Dt1, an inner circumferential piece 42 provided on the other end side of the tooth 35 in the teeth axial direction Dt1 and protruding outward when viewed from the teeth axial direction Dt1 and facing the outer circumferential piece 41 in the teeth axial direction Dt1, and a side wall portion 43 covering the outer periphery of the tooth 35 when viewed from the teeth axial direction Dt1 and connecting the outer periphery piece 41 and the inner circumferential piece 42, and a first opposing surface 41a of the outer circumferential piece 41 facing the inner circumferential piece 42, The space surrounded by the second opposing surface 42a facing the first side and the outer surface 43a of the side wall portion 43 is used as a storage portion 45 for the winding 32, and in a cross section along the teeth axis direction Dt1, a curved portion 47 is formed between the outer peripheral piece 41 and the side wall portion 43, which has a convex arc shape on the opposite side to the storage portion 45. On the inner surface of the curved portion 47 facing the storage portion 45, a first inclined surface 48a is formed extending from the outer surface 43a of the side wall portion 43 to the outer periphery in the teeth radial direction Dt2 at an obtuse angle with respect to the outer surface 43a, a step surface 49 is formed extending along the teeth axis direction Dt1 from the tip of the first inclined surface 48a to the opposite side to the storage portion 45 in the teeth axis direction Dt1, and a second inclined surface 48b is formed extending from the tip of the step surface 49 to the outer periphery in the teeth radial direction Dt2, parallel to the first inclined surface 48a.

[0047] According to this configuration, by forming the curved portion 47 having a convex arc shape on the opposite side to the storage portion 45 between the outer peripheral piece 41 at one end in the teeth axial direction and the side wall portion 43 along the teeth axial direction Dt1, it becomes easier to avoid stress concentration between the outer peripheral piece 41 and the side wall portion 43. In a portion of the curved portion 47 that starts to rise from the side wall portion 43 to the outside in the teeth radial direction (a portion where the inclination angle 47c with respect to the side wall portion 43 is gentle), the inclined surfaces 48a, 48b that partially ensure the rise angles θa, θb are formed, while the step surface 49 along the teeth axial direction Dt1 is included, so that the inclination angle 47c of the rising portion 47a with respect to the side wall portion 43 can be gently suppressed. The space in which the winding 32 can be wound can be expanded in the teeth axial direction Dt1 along the step surface 49. The inclination angles θa, θb of the inclined surfaces 48a, 48b with respect to the side wall surfaces are set, for example, to angles along a tangent t1 to the axial end portions of the teeth of the stacked windings 32. This makes it possible to prevent dead space from being generated at the axial end portions of the teeth of the windings 32. In this way, by providing a shape that combines tapered inclined surfaces 48a, 48b and a step surface 49 along the teeth axis direction Dt1 on the side wall portion 43 side of the curved portion 47, the winding space in the storage portion 45 is expanded at the rising portion 47a of the curved shape, and the number of windings can be increased. Then, by dropping the winding 32 onto the bottom surface (outer surface 43a) of the storage section 45 while pressing the winding 32 against the tapered inclined surfaces 48a, 48b with the tension of the winding 32, it becomes possible to wind the winding 32 without any gaps in the tooth axis direction Dt1 up to the outer peripheral piece 41, thereby improving the adhesion of the winding 32 and improving the space factor (the proportion of the space inside the storage section 45 that the winding 32 occupies).

[0048] In the above insulator structure, the winding 32 is composed of a conductor having a circular cross section and is stacked in the tooth radial direction Dt2 to form multiple layers 32a. The height h from the outer surface 43a to the step surface 49 in the tooth radial direction Dt2 is expressed by the following equation, where D is the maximum diameter of the conductor and n is the number of layers of the winding 32 overlapping in the tooth radial direction Dt2. h=D×(√3 / 2)×(n-1)+D According to this configuration, a step surface 49 can be disposed on the extension of a tangent t2 that contacts the multiple windings 32, on the outer side in the tooth radial direction of one layer 32a of the windings 32 stacked in a bale. This makes it unnecessary to perform step-up or step-down processing of the windings 32 at the step surface 49, reduces the dead space between the layers of the windings 32, prevents collapse of the upper layers, and ensures the alignment of the windings 32.

[0049] In the above insulator structure, in a cross section along the teeth axis direction Dt1, an arc shape 51 having the same diameter as the outer diameter of the circular cross-sectional conductor that constitutes the winding 32 is formed at the corner between the inclined surface 48a and the step surface 49. According to this configuration, by providing a rounded edge with the same diameter as the conductor wire at the corner between inclined surface 48a and step surface 49, an arc shape 51 simulating a conductor wire is formed at the corner between step surface 49 and inclined surface 48a, making it appear as if windings 32 are continuously lined up. This reduces the dead space between the layers of windings 32, prevents collapse of the upper layer, and ensures the alignment of windings 32.

[0050] In the above insulator structure, the distance L from the outer peripheral piece 41 to the inner peripheral piece 42 in the teeth axis direction Dt1 is expressed by the following formula, where Nt is the number of turns of the first layer winding 32 and D is the outer diameter of the circular cross-sectional conductor that constitutes the winding 32. L = D × Nt According to this configuration, by setting the distance L from the outer peripheral piece 41 to the inner peripheral piece 42 in the teeth axis direction Dt1 to an integer multiple of the outer diameter of the conductor (winding 32), it is possible to reduce the dead space between the layers of the winding, prevent collapse of the upper layer, and ensure the alignment of the winding 32.

[0051] In the above insulator structure, the inclined surfaces 48a, 48b are inclined so as to be positioned closer to the outer circumferential piece 41 in the teeth axial direction Dt1 as they approach the outer side in the tooth radial direction. According to this configuration, the inclined surfaces 48a, 48b are inclined so that they are positioned on the outer peripheral piece 41 side (opposite the storage section 45) in the tooth axial direction Dt1 as they move radially outward from the teeth, thereby widening the opening of the storage section 45 on the outer radial side of the teeth, making it easier to wind the winding 32.

[0052] The present invention is not limited to the above-described embodiments, and for example, the insulator structure of the embodiments may be applied to a rotating electric machine other than a vehicle drive motor. For example, the rotating electric machine illustrated in the embodiments is an inner rotor type motor, but is not limited to this configuration. For example, the rotating electric machine may be an outer rotor type in which the rotor is disposed on the outer periphery side of the stator. Furthermore, the rotating electric machine is not limited to a motor, and may be a generator. The insulator structure may be applied to a stator insulator instead of a rotor insulator. The configurations in the above-described embodiments are merely examples of the present invention, and various modifications are possible without departing from the gist of the present invention, such as replacing the components of the embodiments with well-known components. [Explanation of symbols]

[0053] 1 Motor (rotating electric machine) 2 Rotors 3 Stator 21 Rotation axis 22 Rotor core 32 windings 32a layer 35 Teeth 36 Slots 37 Coil 38 Insulator 41 Outer piece 41a First opposing surface 42 Inner peripheral piece 42a Second facing surface 43 Side wall 43a External surface 45 Storage area 47 Curved section 47c Tilt angle 48a First slope θa Inclination angle 48b Second slope θb Tilt angle 49 Step surface 51 Arc Shape h Height of the step D Outer diameter (maximum diameter) n Number of layers L distance Nt Number of turns Da Axial direction (motor axis direction) Dc Circumferential direction (motor circumferential direction) Dr Radial direction (motor radial direction) Dt1 Teeth axial direction Dt2 Teeth radial direction

Claims

1. In the structure of the insulator attached to each of a plurality of teeth arranged in a circumferential direction of the motor, an outer circumferential piece provided at one end of the tooth in a teeth axial direction along a motor radial direction and protruding outward as viewed from the teeth axial direction; an inner peripheral piece provided at another end of the tooth in the teeth axial direction, protruding outwardly as viewed from the teeth axial direction, and facing the outer peripheral piece in the teeth axial direction; a side wall portion covering an outer periphery of the tooth when viewed from the teeth axial direction and connecting the outer periphery piece and the inner periphery piece, a space surrounded by a first opposing surface of the outer peripheral piece facing the inner peripheral piece, a second opposing surface of the inner peripheral piece facing the outer peripheral piece, and an outer surface of the side wall portion serves as a storage section for the winding; In a cross section along the teeth axis direction, a curved portion having a convex arc shape is formed between the outer peripheral piece and the side wall portion on the opposite side to the storage portion, The inner surface of the curved portion facing the storage portion has a first inclined surface extending from an outer surface of the side wall portion toward an outer periphery in a radial direction of the teeth at an obtuse angle with respect to the outer surface; a step surface extending along the teeth axis direction from a tip of the first inclined surface to an opposite side to the storage portion in the teeth axis direction; An insulator structure characterized in that a second inclined surface is formed extending parallel to the first inclined surface from the tip of the step surface toward the outer periphery in the tooth radial direction.

2. The windings are made of conductors with a circular cross section, stacked radially around the teeth to form multiple layers. The insulator structure according to claim 1, characterized in that the height h from the outer surface to the step surface in the radial direction of the teeth is expressed by the following formula, where D is the maximum diameter of the conductor and n is the number of layers of windings overlapping in the radial direction of the teeth. h=D×(√3 / 2)×(n-1)+D

3. 3. An insulator structure as described in claim 1 or 2, characterized in that in a cross section along the tooth axial direction, the corner between the inclined surface and the step surface is formed into an arc shape having the same diameter as the outer diameter of the circular cross-sectional conductor that constitutes the winding.

4. An insulator structure as described in claim 1 or 2, characterized in that the distance L from the outer peripheral piece to the inner peripheral piece in the tooth axial direction is expressed by the following formula, where Nt is the number of turns of the first layer winding and D is the outer diameter of the conductor having a circular cross section that constitutes the winding. L = D x Nt

5. 3. The insulator structure according to claim 1, wherein the inclined surfaces are inclined so as to be positioned toward one side of the outer periphery in the axial direction of the teeth as they move radially outward of the teeth.

Images