Insulator structure

Abstract

The invention provides an insulator structure. The insulator (38) includes an outer peripheral piece (41), an inner peripheral piece (42) facing the outer peripheral piece in a tooth axial direction (Dt1), and a side wall portion (43) connecting the outer peripheral piece and the inner peripheral piece, a space surrounded by the outer peripheral piece, the inner peripheral piece, and the side wall portion serves as a housing portion (45) of the winding (32), and a bent portion (47) is formed between the outer peripheral piece and the side wall portion. A first inclined surface (48a) extending at an obtuse angle from the outer surface (43a) of the side wall part (43) toward the outer peripheral side in the tooth radial direction (Dt2), and a stepped surface (49) extending from the tip of the first inclined surface toward the side opposite to the housing part along the tooth axial direction (Dt1) are formed on the inner surface of the curved part facing the housing part (45). And a second inclined surface (48b) extending parallel to the first inclined surface from the tip of the stepped surface toward the outer peripheral side in the tooth radial direction (Dt2).

Description

Technical Field

[0001] The present invention relates to insulator structures. Background Art

[0002] In recent years, efforts to realize a low-carbon society or a decarbonized society have become more active, and research and development related to electrification technology has also been carried out in order to reduce CO2 emissions and improve energy efficiency in vehicles.

[0003] For example, in rotating electrical machines such as vehicle drive motors, a winding excitation type is sometimes used instead of the mainstream embedded magnet type. In a winding excitation type motor, a coil is arranged on the rotor instead of a permanent magnet, and a current is passed through the coil to generate a magnetic flux in the rotor. The winding excitation type motor can adjust the magnetic flux of the rotor, so high-efficiency operation can be expected, and since permanent magnets are not used, there is no need to worry about the stable supply of rare earth elements.

[0004] That is, at least one of the stator and the rotor of the motor includes: an annular ring portion; a plurality of cores (teeth) radially protruding radially inward or outward of the annular portion; and a coil with a conducting wire wound around the outer circumference of each core.

[0005] For example, Japanese Patent Application Laid-Open No. 2007-135360 discloses a structure in which a step having a specific height is provided on the surface of a tooth (specifically, the surface of an insulator) in order to increase the space factor of the conductor in the slot between the cores. Summary of the invention

[0006] In the above-mentioned prior art, flange-shaped outer and inner pieces are provided on both sides of the tooth in the axial direction, and the winding of the coil is stored in a stacked state between these outer and inner pieces. The outer and inner pieces are arranged so that the planar opposing surfaces perpendicular to the tooth axial direction are opposed to each other in the tooth axial direction. On the other hand, the wire constituting the winding may be bent due to wire curling, which may impair the close contact with the tooth or reduce the arrangement.

[0007] An object of the present invention is to provide an insulator structure that can improve the close contact between the winding and the teeth and improve the space factor. In addition, the present invention further contributes to improving energy efficiency.

[0008] The insulator structure of the first scheme of the present invention is a structure of insulators respectively mounted on a plurality of teeth arranged along the circumferential direction of the motor, wherein the insulator structure comprises: an outer peripheral plate, which is arranged on one end side of the tooth axial direction of a tooth among the plurality of teeth, and the outer peripheral plate extends outwardly when viewed from the tooth axial direction, wherein the tooth axial direction is along the radial direction of the motor; an inner peripheral plate, which is arranged on the other end side of the tooth axial direction of the tooth, and the inner peripheral plate extends outwardly when viewed from the tooth axial direction, and the inner peripheral plate is opposite to the outer peripheral plate in the tooth axial direction; and a side wall portion, which covers the outer periphery of the tooth when viewed from the tooth axial direction, and connects the outer peripheral plate with the inner peripheral plate, and connects the first opposing surface of the outer peripheral plate facing the inner peripheral plate side and the inner peripheral plate facing the inner peripheral plate side. The space surrounded by the second opposing surface toward the outer peripheral piece and the outer surface of the side wall portion serves as a storage portion for the winding. In the cross section along the axial direction of the tooth, a curved portion is formed between the outer peripheral piece and the side wall portion. The curved portion is in the shape of an arc convex toward the side opposite to the storage portion. A first inclined surface, a step surface, and a second inclined surface are formed on the inner surface of the curved portion toward the storage portion. The first inclined surface extends from the outer surface to the outer peripheral side in the tooth radial direction at an obtuse angle relative to the outer surface of the side wall portion, and the step surface extends along the axial direction of the tooth from the front end of the first inclined surface to the side opposite to the storage portion in the axial direction of the tooth. The second inclined surface extends from the front end of the step surface to the outer peripheral side in the tooth radial direction in parallel with the first inclined surface.

[0009] According to this structure, a curved portion is formed between the outer peripheral piece at one end side in the tooth axial direction and the side wall portion along the tooth axial direction, and the curved portion is in the shape of an arc convex to the side opposite to the storage portion, thereby making it easy to avoid stress concentration between the outer peripheral piece and the side wall portion. In the curved portion, the portion that rises from the side wall portion toward the outer side in the tooth radial direction (the portion with a gentle inclination angle relative to the side wall portion) forms an inclined surface that locally ensures the rising angle, while including a step surface along the tooth axial direction, thereby making it possible to suppress the inclination angle of the rising portion relative to the side wall portion to be gentle. The space in which the winding can be wound can be expanded in the tooth axial direction along the step surface. The inclination angle of the inclined surface relative to the side wall surface is set, for example, to the angle of the tangent along the tooth axial end of the stacked winding. As a result, the generation of a dead space at the tooth axial end of the winding can be suppressed.

[0010] In this way, by providing a shape combining a tapered inclined surface and a stepped surface along the tooth axis on the side wall of the curved portion, the winding space in the storage portion is expanded in the rising portion of the curved shape, and the number of windings can be increased.

[0011] Furthermore, the winding is pressed against the conical inclined surface by the tension of the winding, and is made to fall into the bottom surface (outer surface) of the storage portion, thereby being able to be wound onto the outer peripheral sheet without a gap in the axial direction of the tooth, thereby improving the close contact of the winding and increasing the space factor (the proportion of the winding relative to the space in the storage portion).

[0012] A second aspect of the present invention may be such that, based on the insulator structure of the first aspect, the winding is composed of a conductor having a circular cross section and is stacked in a plurality of layers in the tooth radial direction, and when the maximum diameter of the conductor is set to D and the number of layers of the winding stacked in the tooth radial direction is set to n, the height h from the outer side surface to the step surface in the tooth radial direction is expressed by the following formula:

[0013] h=D×(√3 / 2)×(n-1)+D.

[0014] According to this structure, a step surface can be arranged on the extension of a tangent line tangent to a plurality of windings on the radially outer side of a tooth of a layer in the laminated winding. Therefore, it is not necessary to perform an up-step or down-step process on the step surface of the winding, and the dead zone between the layers of the winding can be reduced to prevent the winding of the upper layer from collapsing, thereby ensuring the arrangement of the winding.

[0015] A third embodiment of the present invention is based on the insulator structure of the first or second embodiment, and can also be that, in a cross section along the tooth axis, an arc shape with the same diameter as the outer diameter of the conductor forming the circular cross section of the winding is formed at the corner between the inclined surface and the step surface.

[0016] According to this structure, by applying a round chamfer with the same diameter as the conductor to 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, which looks like a continuous arrangement of windings. As a result, the dead zone between the layers of the windings can be reduced to prevent the winding of the upper layer from collapsing, thereby ensuring the arrangement of the windings.

[0017] A fourth aspect of the present invention is based on the insulator structure of any one of the first to third aspects, and may be such that, when the number of turns of the winding of the first layer is set to Nt and the outer diameter of the conductor having a circular cross section constituting the winding is set to D, the distance L from the outer peripheral piece to the inner peripheral piece in the tooth axial direction is expressed by the following formula:

[0018] L=D×Nt.

[0019] According to this structure, by setting the distance from the outer peripheral piece to the inner peripheral piece in the tooth axis direction to an integer multiple of the outer diameter of the conductor (winding), the dead space between the layers of the winding can be reduced to prevent the winding of the upper layer from collapsing, thereby ensuring the arrangement of the winding.

[0020] According to a fifth aspect of the present invention, in the insulator structure of any one of the first to fourth aspects, the inclined surface may be inclined so as to be located closer to the outer peripheral piece in the tooth axial direction as it approaches the outer side in the tooth radial direction.

[0021] According to this structure, the inclined surface is inclined so that it is located closer to the outer side in the tooth radial direction (the side opposite to the storage portion) in the tooth axial direction. As a result, the opening of the storage portion on the outer side in the tooth radial direction is expanded, making it easier to wind the winding.

[0022] According to the aspect of the present invention, it is possible to provide an insulator structure capable of improving the close contact between the winding and the teeth and improving the space factor. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is an exploded perspective view of a motor in an embodiment of the present invention.

[0024] Figure 2 It is a plan view of a portion of the circumferential direction of the rotor of the above-mentioned motor as viewed from the axial direction, including a portion of the cross section.

[0025] Figure 3 Yes means Figure 2 An enlarged view of a cross-sectional portion of the coil is shown.

[0026] Figure 4 yes Figure 3 Enlarged view of part IV. DETAILED DESCRIPTION

[0027] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0028] <Motor 1>

[0029] Figure 1 It is an exploded perspective view of a motor (rotating electric machine) 1 according to an embodiment of the present invention.

[0030] like Figure 1 As shown, the motor 1 includes a rotor 2, a stator 3, and a case (not shown) covering the rotor 2 and the stator 3. In the present embodiment, the rotor 2 is arranged on the inner peripheral side with respect to the stator 3. That is, the motor 1 is an inner rotor type motor.

[0031] The motor 1 of the embodiment is a drive motor for an electric vehicle. In addition, the motor 1 of the embodiment is a winding excitation type motor, and has a rotor structure using an excitation winding (coil 37) instead of a permanent magnet. The motor 1 generates magnetic flux in the rotor 2 by passing a direct current from the outside to the excitation winding, and the excitation magnetic flux can be adjusted.

[0032] <Rotor 2>

[0033] The rotor 2 includes a rotating shaft 21 , a rotor core 22 , a plurality of magnetic pole portions 23 , and a commutator 24 .

[0034] The rotating shaft 21 extends in the axial direction (motor axial direction) Da. The rotating shaft 21 is supported by a housing (not shown) via a bearing (not shown). The rotating shaft 21 is supported to be rotatable in the circumferential direction (motor circumferential direction) Dc around the axis C extending in the axial direction Da.

[0035] The rotor core 22 is arranged outside (on the outer peripheral side) of the radial direction Dr (motor radial direction) centered on the axis C relative to the rotating shaft 21. The rotor core 22 is formed in a cylindrical shape with the axis C as the axis center. When viewed from the axial direction Da, a shaft insertion hole 22a for the rotating shaft 21 to pass through is formed in the center portion of the rotor core 22. The rotor core 22 can rotate integrally with the rotating shaft 21 in the circumferential direction Dc.

[0036] The plurality of magnetic pole portions 23 are arranged at equal intervals along the circumferential direction Dc at the outer periphery of the rotor core 22. Each magnetic pole portion 23 includes a coil 37. The coil 37 is formed by winding a winding 32 around the outer periphery of a tooth 35 formed on the rotor core 22 via an insulator 38. The details of the coil 37 and the insulator 38 will be described later.

[0037] The commutator 24 is coaxially provided at one end of the rotating shaft 21. The commutator 24 is rotatable in the circumferential direction Dc integrally with the rotating shaft 21. The brush 25 supported by the housing is in contact with the commutator 24 in the radial direction Dr so as to face the commutator 24.

[0038] <Stator 3>

[0039] The stator 3 is disposed on the outer peripheral side of the rotor core 22 in the radial direction Dr with a gap (air gap) therebetween. The stator 3 is fixed to the inner peripheral side of the housing in the radial direction Dr. The stator 3 has a stator core (not shown) and a plurality of magnetic poles (not shown).

[0040] <Details of Rotor 2>

[0041] Hereinafter, the rotor 2 will be described in more detail.

[0042] like Figure 2 As shown, the rotor core 22 integrally includes an annular portion 34 and a plurality of teeth 35 .

[0043] The annular portion 34 is formed on the inner circumference side (rotation 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.

[0044] The plurality of teeth 35 are formed at regular intervals along 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.

[0045] The slots 36 and the teeth 35 are formed in the same number (eight in the embodiment). The rotor core 22 may be divided into a plurality of teeth 35 in the circumferential direction Dc. Figure 2 The line Ct in φ represents the central axis along the central axis of the tooth 35 (the protruding direction of the tooth 35 (motor radial direction Dr)). Hereinafter, the protruding direction of the tooth 35 is referred to as the tooth axial direction Dt1, and the direction orthogonal to the tooth axial direction Dt1 is referred to as the tooth radial direction Dt2.

[0046] The winding 32 is a conductive wire (e.g., a copper wire) and is held in the rotor core 22 in the form of a coil 37. The winding 32 is wound around the plurality of teeth 35 via an insulator 38 made of insulating resin. When viewed from the tooth axial direction Dt1, the winding 32 is wound in a manner that a plurality of layers 32a are stacked on the outer periphery of the tooth 35. By winding the winding 32 around each tooth 35, a plurality of coils 37 arranged at intervals in the circumferential direction Dc are formed on the rotor 2. 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.

[0047] <Insulator 38>

[0048] like Figure 2 , Figure 3 As shown, the insulator 38 of the embodiment includes: a flange-shaped outer peripheral piece 41 provided at one end side (motor outer peripheral side) in the tooth axial direction Dt1; a flange-shaped inner peripheral piece 42 provided at the other end side (motor inner peripheral side) in the tooth axial direction Dt1; and a cylindrical side wall portion 43 connecting the outer peripheral piece 41 and the inner peripheral piece 42. The internal space surrounded by the facing surfaces 41a and 42a of the outer peripheral piece 41 and the inner peripheral piece 42 and the outer side surface 43a of the side wall portion 43 on three sides is a storage portion 45, and the storage portion 45 stores the coil 37 of the stacked winding 32. The groove 36 is formed by a pair of adjacent storage portions 45 in the motor circumferential direction Dc.

[0049] The windings 32 are densely arranged in the housing portion 45 by so-called lamination. Figure 3 The two-dot chain line 45 a in FIG. 4 is an imaginary line between the outer ends of the outer peripheral piece 41 and the inner peripheral piece 42 on the outer side in the tooth radial direction, and indicates the outer shape of the housing portion 45 on the outer side in the tooth radial direction.

[0050] Figure 2 part of Figure 3 and Figure 4 The cross sections shown are cross sections along the tooth axial 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 each figure".

[0051] like Figure 3As shown, at the corner between the outer peripheral piece 41 and the side wall portion 43, a curved portion 47 curved in an arc shape is formed in the cross section shown in each figure. A plurality of (for example, two) inclined surfaces 48a, 48b (a first inclined surface 48a, a second inclined surface 48b) are formed on the inner peripheral side of the curved portion 47. The plurality of inclined surfaces 48a, 48b extend toward the tooth radial outer side at the same inclination angles θa, θb in the cross section shown in each figure. Between the plurality of inclined surfaces 48a, 48b, a step surface 49 extending linearly along the tooth axial direction Dt1 is formed in the cross section shown in each figure.

[0052] The winding 32 of the layer 32a (first layer) closest to the side wall portion 43 is wound while being pressed against the outer side surface 43a of the side wall portion 43 under the action of the tension during the winding operation. As described later, the distance L between the outer peripheral piece 41 and the inner peripheral piece 42 in the tooth axial direction Dt1 is set to an integral multiple of the outer diameter (diameter) D of the conductor constituting the winding 32. As a result, the winding 32 is wound while being pressed inward in the tooth radial direction, and the winding 32 is arranged without a gap in the tooth axial direction Dt1.

[0053] By connecting the plurality of inclined surfaces 48a and 48b via the step surface 49 along the tooth axial direction Dt1, the portion of the curved portion 47 that rises from the side wall portion 43 toward the outer side in the tooth radial direction (the portion where the inclination angle 47c with respect to the side wall portion 43 is gentle, hereinafter referred to as the rising portion 47a) has the following effect. That is, in the rising portion 47a of the curved portion 47, the step surface 49 along the tooth axial direction Dt1 is provided between the plurality of inclined surfaces 48a and 48b, thereby forming the plurality of inclined surfaces 48a and 48b that locally ensure the rising angles (inclination angles) θa and θb, while suppressing the inclination angle 47c of the rising portion 47a with respect to the side wall portion 43 to be gentle.

[0054] The "portion that rises from the side wall portion 43 toward the outer side in the tooth radial direction" of the curved portion 47, for example, in the cross sections shown in the figures, refers to a range of about half a circumference on the side of the side wall portion 43 in the curved portion 47. In addition, the "inclination angle 47c relative to the side wall portion 43" of the rising portion 47a, for example, in the cross sections shown in the figures, refers to the inclination angle of the straight line 47b connecting the end of the rising portion 47a on the side of the side wall portion 43 and the end on the outer side in the tooth radial direction.

[0055] like Figure 4As shown, a plurality of inclined surfaces 48a, 48b are formed at one end of the stacked winding 32 in the tooth axial direction in parallel with the first tangent line t1, and the first tangent line t1 is tangent to the plurality of windings 32. Even when the number of layers of the winding 32 increases, each inclined surface 48a, 48b is tangent to the winding 32 at one end of the tooth axial direction of each layer 32a. The winding 32 at one end of the tooth axial direction of each layer 32a is arranged along each inclined surface 48a, 48b. As a result, the dead zone at one end of the tooth axial direction of each layer 32a is reduced.

[0056] like Figure 4 As shown, if the windings 32 with circular cross sections are stacked, multiple windings 32 are stacked in an equilateral triangle shape at each location of the coil 37. In a pair of overlapping layers 32a, the distance A in the tooth radial direction Dt2 between the axes 32c of the windings 32 in each layer 32a is expressed by the following formula (1).

[0057] A=√3·D / 2=(√3 / 2)·D (D is the maximum diameter (outer diameter) of the winding 32)···(1)

[0058] The height T of the stacked two-layer winding 32 in the tooth radial direction Dt2 is T=A+D.

[0059] When the number of layers increases, for example, T=2·A+D in a three-layer winding 32, and T=3·A+D in a four-layer winding 32. That is, the height T of the tooth radial direction Dt2 of the multilayer winding 32 is expressed by the following equation (2).

[0060] 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)

[0061] In the embodiment, the height h from the outer side surface 43 a of the side wall portion 43 to the step surface 49 in the tooth radial direction Dt2 is set to the height T represented by the above-mentioned formula (2).

[0062] Thus, the height of the second tangent line t2 that touches any of the layers 32a of the stacked winding 32 from the outside in the tooth radial direction and the height T of the step surface 49 become the same height. The surface along the second tangent line t2 and the step surface 49 are continuous in the same plane. Therefore, when the winding 32 is further wound at a position outside the tooth radial direction than the height T of the step surface 49, the winding 32 is wound on a surface at the same height in the tooth radial direction Dt2 including the step surface 49. As a result, the outer peripheral surface of the coil 37 is formed in the same plane.

[0063] In the cross section along the tooth axial direction Dt1, a round chamfer is applied to the corner between the step surface 49 and the inclined surface 48a, and the round chamfer forms an arc shape 51 with the same diameter as the outer diameter of the winding 32. As a result, a simulated winding 32 exists at the corner between the step surface 49 and the inclined surface 48a, and it is a form as if the winding 32 is continuously arranged on the surface at the same height as the step surface 49. As a result, when the winding 32 is wound on the surface at the same height as the step surface 49, it is easy to form the layer 32a of the winding 32 in the same plane until it reaches the step surface 49.

[0064] It should be noted that the step surface 49 of the embodiment extends linearly along the tooth axial direction Dt1 in the cross section along the tooth axial direction Dt1, but the present invention is not limited to this structure. For example, the step surface 49 may be formed into a waveform having a concave shape along the outer diameter of the winding 32 in the cross section along the tooth axial direction Dt1. In this case, the close contact of the winding 32 on the step surface 49 to the step surface 49 is improved, and it is easier to form the layer 32a of the winding 32 on the surface at the same height as the step surface 49 into the same plane.

[0065] like Figure 3 As shown, the distance L between the inner peripheral piece 42 and the outer peripheral piece 41 in the tooth axial direction Dt1 is expressed by the following formula (3).

[0066] L = D·Nt (Nt is the number of turns (natural number) of the first layer winding 32) ... (3)

[0067] Thus, if the first layer winding 32 is wound a predetermined number of turns with a predetermined tension, the first layer winding 32 is arranged without gaps in the tooth axial direction Dt1 between the inner peripheral piece 42 and the outer peripheral piece 41. Therefore, the dead zone around the first layer can be reduced and the space factor of the winding 32 can be increased.

[0068] Each inclined surface 48a, 48b is inclined so as to be located further outward in the tooth radial direction (from the center of the tooth axial direction of the insulator 38 toward the outer peripheral piece 41 side). As a result, the number of turns of the winding 32 in the tooth axial direction Dt1 increases as the layer 32a is located further outward in the tooth radial direction. In addition, the storage portion 45 is expanded in the tooth axial direction Dt1 as the layer 32a is located further outward in the tooth radial direction, so that the winding operation of the winding 32 becomes easier.

[0069] In the cross section along the tooth axial direction Dt1, the inclination angles θa and θb of each inclined surface 48a and 48b relative to the outer side surface 43a of the side wall portion 43 (the tooth axial direction Dt1) are set to 60 degrees (the angle along the distribution of the stacked windings). Thus, the dead space between the layers of the winding 32 is reduced by stacking, and at one end of the stacked winding 32 in the tooth axial direction, the winding 32 of each layer 32a is arranged in a manner tangent to each of the 60-degree inclined surfaces 48a and 48b, thereby reducing the dead space at one end of the winding 32 in the tooth axial direction. Therefore, the space factor can be increased while improving the close contact of the winding 32.

[0070] In the embodiment, the structure has two inclined surfaces 48a, 48b and a single stepped surface 49 formed between the two inclined surfaces 48a, 48b, but is not limited to this structure. For example, a structure having three or more inclined surfaces and two or more stepped surfaces formed between two adjacent inclined surfaces may also be used. In this case, the inclination angles θa and θb of each inclined surface relative to the outer side surface 43a (tooth axial direction Dt1) are preferably formed to be 60 degrees.

[0071] The facing surface 42a of the inner peripheral piece 42 is an inclined surface that is inclined so as to be located further outward in the tooth axial direction (from the center of the tooth axial direction of the insulator 38 toward the inner peripheral piece 42 side) as it is closer to the tooth radial direction. The inclined surface of the inner peripheral piece 42 is formed parallel to the tangent line that is tangent to the plurality of windings 32 at the other end in the tooth axial direction of the stacked windings 32, similarly to the inclined surfaces 48a and 48b of the outer peripheral piece 41. In addition, the inclined surface of the inner peripheral piece 42 is set at an inclination angle of 60 degrees with respect to the outer side surface 43a (tooth axial direction Dt1) of the side wall portion 43.

[0072] As described above, the insulator structure in the above-mentioned embodiment is a structure of an insulator 38 respectively mounted on a plurality of teeth 35 arranged along the motor circumferential direction Dc, and comprises: an outer peripheral piece 41, which is arranged on one end side of the tooth axial direction Dt1 in the tooth 35, and the outer peripheral piece 41 protrudes to the outer peripheral side when viewed from the tooth axial direction Dt1, wherein the tooth axial direction Dt1 is along the motor radial direction Dr; an inner peripheral piece 42, which is arranged on the other end side of the tooth axial direction Dt1 in the tooth 35, and the inner peripheral piece 42 protrudes to the outer peripheral side when viewed from the tooth axial direction Dt1, and the inner peripheral piece 42 is opposite to the outer peripheral piece 41 in the tooth axial direction Dt; and a side wall portion 43, which covers the outer periphery of the tooth 35 when viewed from the tooth axial direction Dt1, and connects the outer peripheral piece 41 and the inner peripheral piece 42, wherein the first opposing surface 41a of the outer peripheral piece 41 facing the inner peripheral piece 42 and the first opposing surface 41a of the inner peripheral piece 42 facing the outer peripheral piece 4 1, and the space surrounded by the second opposing surface 42a on the side and the outer side surface of the side wall portion 43 serves as a storage portion 45 for the winding 32. In the cross section along the tooth axial direction Dt1, a bent portion 47 is formed between the outer peripheral piece 41 and the side wall portion 43. The bent portion 47 is in an arc shape convex to the side opposite to the storage portion 45. A first inclined surface 48a, a step surface 49 and a second inclined surface 48b are formed on the inner side surface of the bent portion 47 facing the storage portion 45 side. The first inclined surface 48a extends from the outer side surface 43a to the outer peripheral side of the tooth radial direction Dt2 at an obtuse angle relative to the outer side surface 43a of the side wall portion 43, the step surface 49 extends along the tooth axial direction Dt1 from the front end of the first inclined surface 48a to the side opposite to the storage portion 45 on the tooth axial direction Dt1, and the second inclined surface 48b extends from the front end of the step surface 49 to the outer peripheral side of the tooth radial direction Dt2 in parallel with the first inclined surface 48a.

[0073] According to this structure, a curved portion 47 is formed between the outer peripheral piece 41 at one end side in the tooth axial direction and the side wall portion 43 along the tooth axial direction Dt1. The curved portion 47 is in an arc shape convex to the side opposite to the housing portion 45, thereby making it easy to avoid stress concentration between the outer peripheral piece 41 and the side wall portion 43. In the curved portion 47, the portion that rises from the side wall portion 43 to the outside in the tooth radial direction (the portion with a gentle inclination angle 47c relative to the side wall portion 43) is formed with inclined surfaces 48a and 48b that partially ensure the rising angles θa and θb, and includes a step surface 49 along the tooth axial direction Dt1, thereby making it possible to suppress the inclination angle 47c of the rising portion 47a relative to the side wall portion 43 to be gentle. The space in which the winding 32 can be wound can be expanded in the tooth axial direction Dt1 along the step surface 49. The inclination angles θa and θb of the inclined surfaces 48a and 48b relative to the side wall surface are set, for example, to the angles along the tangent t1 of the end portion of the stacked winding 32 in the tooth axial direction.

[0074] This can suppress the occurrence of a dead zone at the end portion of the winding 32 in the tooth axial direction.

[0075] In this way, by providing a shape combining conical inclined surfaces 48a, 48b and a step surface 49 along the tooth axis Dt1 on the side wall portion 43 of the curved portion 47, the winding space in the storage portion 45 is expanded in the curved rising portion 47a, thereby increasing the number of windings.

[0076] Furthermore, while the winding 32 is pressed against the conical inclined surfaces 48a, 48b by the tension of the winding 32, the winding 32 is made to fall into the bottom surface (outer surface 43a) of the storage portion 45, thereby being able to wind the winding 32 onto the peripheral sheet 41 without a gap in the tooth axial direction Dt1, thereby improving the close contact of the winding 32 and improving the space factor (the proportion of the winding 32 relative to the space in the storage portion 45).

[0077] In the above-mentioned insulator structure, the winding 32 is composed of a conductor with a circular cross-section, and is stacked on the tooth radial direction Dt2 to form a plurality of layers 32a. When the maximum diameter of the conductor is set to D and the number of layers of the winding 32 overlapped on the tooth radial direction Dt2 is set to n, the height h from the outer side surface 43a to the step surface 49 on the tooth radial direction Dt2 is expressed by the following formula.

[0078] h=D×(√3 / 2)×(n-1)+D

[0079] According to this configuration, the step surface 49 can be arranged on the outer side in the tooth radial direction of one layer 32 a in the stacked windings 32 as an extension of the tangent line t2 that touches the plurality of windings 32 .

[0080] Therefore, the winding 32 does not need to be stepped up or down on the step surface 49 , and the dead space between layers of the winding 32 can be reduced to prevent the winding collapse of the upper layer, thereby ensuring the arrangement of the winding 32 .

[0081] In the above insulator structure, in the cross section along the tooth axis direction Dt1 , an arc shape 51 having the same diameter as the outer diameter of the conductor forming the circular cross section of the winding 32 is formed at the corner between the inclined surface 48 a and the stepped surface 49 .

[0082] According to this structure, by performing a round chamfer with the same diameter as the conductor on the corner between the inclined surface 48a and the step surface 49, an arc shape 51 simulating the conductor is formed at the corner between the step surface 49 and the inclined surface 48a, and it becomes a form as if the windings 32 are continuously arranged. As a result, the dead zone between the layers of the windings 32 can be reduced to prevent the winding of the upper layer from collapsing, and the arrangement of the windings 32 can be ensured.

[0083] In the above-mentioned insulator structure, when the number of turns of the first layer winding 32 is Nt and the outer diameter of the conductor having a circular cross section constituting the winding 32 is D, the distance L from the outer peripheral piece 41 to the inner peripheral piece 42 in the tooth axial direction Dt1 is expressed by the following formula.

[0084] L=D×Nt

[0085] According to this structure, by setting the distance L from the outer peripheral piece 41 to the inner peripheral piece 42 in the tooth axial direction Dt1 to an integer multiple of the outer diameter of the conductor (winding 32), the dead zone between the layers of the winding can be reduced to prevent the winding collapse of the upper layer, thereby ensuring the arrangement of the winding 32.

[0086] In the above-described insulator structure, the inclined surfaces 48 a and 48 b are inclined so as to be located closer to the outer side in the tooth radial direction than to the outer side in the tooth axial direction Dt1 .

[0087] According to this structure, the inclined surfaces 48a and 48b are inclined in such a manner that they are located closer to the outer side in the tooth radial direction (the side opposite to the storage portion 45) in the tooth axial direction Dt1. As a result, the opening of the storage portion 45 on the outer side in the tooth radial direction is enlarged, making it easier to wind the winding 32.

[0088] It should be noted that the present invention is not limited to the above-mentioned embodiments. For example, the insulator structure of the embodiment can also be applied to rotating electrical machines other than vehicle drive motors. For example, the rotating electrical machine illustrated in the embodiment is an inner rotor type motor, but is not limited to this structure. For example, the rotating electrical machine can also be an outer rotor type in which the rotor is arranged on the outer peripheral side relative to the stator. In addition, the rotating electrical machine is not limited to a motor, but can also be a generator. It can also be applied to the insulator of the stator instead of the insulator of the rotor.

[0089] Furthermore, the configuration in the above-described embodiment is an example of the present invention, and various modifications can be made without departing from the gist of the present invention, such as replacing the components of the embodiment with known components.

Claims

1. An insulator structure, which is a structure of insulators respectively mounted on a plurality of teeth arranged along the circumferential direction of a motor, wherein: The insulator structure comprises: An outer peripheral piece, which is arranged at one end side of the tooth axial direction of a tooth among the plurality of teeth, and the outer peripheral piece extends outwardly when viewed from the tooth axial direction, wherein the tooth axial direction is along the radial direction of the motor; an inner peripheral piece provided at the other end side of the tooth in the tooth axial direction, the inner peripheral piece extending toward the outer peripheral side when viewed from the tooth axial direction, and the inner peripheral piece and the outer peripheral piece facing each other in the tooth axial direction; and a side wall portion that covers the outer periphery of the tooth when viewed from the axial direction of the tooth and connects the outer peripheral piece to the inner peripheral piece, The space surrounded by the first facing surface of the outer peripheral piece facing the inner peripheral piece, the second facing surface of the inner peripheral piece facing the outer peripheral piece, and the outer side surface of the side wall portion is used as a storage portion for the winding. In a cross section along the tooth axis, a curved portion is formed between the outer peripheral piece and the side wall portion, and the curved portion is in an arc shape convex to a side opposite to the storage portion. A first inclined surface, a stepped surface, and a second inclined surface are formed on the inner side surface of the curved portion facing the storage portion. The first inclined surface extends from the outer surface in the tooth radial direction to the outer peripheral side at an obtuse angle with respect to the outer surface of the side wall portion. The step surface extends along the tooth axis from the front end of the first inclined surface to the side opposite to the receiving portion in the tooth axis direction. The second inclined surface extends parallel to the first inclined surface from the front end of the step surface toward the outer peripheral side in the tooth radial direction.

2. The insulator structure according to claim 1, wherein: The winding is composed of a conductor having a circular cross section and is stacked in a radial direction of the tooth to form a plurality of layers. When the maximum diameter of the conductor is set to D and the number of layers of the windings overlapped in the tooth radial direction is set to n, the height h from the outer side surface to the step surface in the tooth radial direction is expressed by the following formula: Formula: h=D×(√3 / 2)×(n-1)+D.

3. The insulator structure according to claim 1 or 2, wherein: In the cross section along the tooth axis direction, a corner portion between the inclined surface and the stepped surface is formed in an arc shape having the same diameter as the outer diameter of the conductive wire forming the circular cross section of the winding.

4. The insulator structure according to claim 1 or 2, wherein: When the number of turns of the winding of the first layer is Nt and the outer diameter of the conductor having a circular cross section constituting the winding is D, the distance L from the outer peripheral piece to the inner peripheral piece in the tooth axial direction is expressed by the following formula: Formula: L=D×Nt.

5. The insulator structure according to claim 1 or 2, wherein: The inclined surface is inclined so as to be located closer to the outer side in the tooth radial direction than to the outer side in the tooth axial direction.

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