Method for manufacturing an electric motor and electric motor

Abstract

Avoid an increase in the manufacturing cost of the electric motor and enhance the reliability of the conducting wire wound around the first layer of the winding portion. 【Solution means】The method for manufacturing an electric motor includes a stator core having an annular yoke portion and a tooth portion extending in the radial direction of the yoke portion from the yoke portion, an insulator having a winding cylinder portion attached to the tooth portion, and a winding portion in which a plurality of layers are formed by a winding wire in which a conducting wire is wound around the winding cylinder portion and the tooth portion. The method for manufacturing an electric motor is such that when the winding pitch of the conducting wire wound side by side in the radial direction of the yoke portion is P and the outer diameter of the conducting wire is B, in the radial direction, the conducting wire is wound around the first layer of the winding portion so as to satisfy P≧B, and P is provided in at least one layer after the second layer of the winding portion.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing an electric motor and an electric motor.

Background Art

[0002] As an electric motor, there is provided a stator core and an insulator provided at an end portion of the stator core, and a winding portion having a plurality of layers is formed by a winding wire in which a conductor wire is wound in a concentrated winding manner around a tooth portion of the stator core and a bobbin portion of the insulator. In this type of electric motor, miniaturization and high efficiency are achieved by increasing the occupation ratio of the conductor wire in the winding portion.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the electric motor described in Patent Document 1, the surface of the bobbin portion of the insulator is formed flat along the radial direction of the stator core. Further, the winding portion includes a first layer formed by winding a conductor wire along the surface of the bobbin portion from one end side (outer diameter side) to the other end side (inner diameter side) in the radial direction of the stator core, and a second layer formed by laminating so as to overlap the first layer and winding the conductor wire from the other end side (inner diameter side) to the one end side (outer diameter side) in the radial direction of the stator core.

[0005] In such an electric motor, in order to increase the occupation ratio of the winding part, when the winding pitch of the first layer of conductors wound side by side in the radial direction of the stator core (the amount of movement of the nozzle per turn in the winding process using a winding machine) is reduced, when forming the first layer of the winding part, a part of the later-wound winding may ride on the previously wound winding. At this time, the later-wound winding does not line up on the other end side (inner diameter side) than the previously wound winding, but enters the one end side (outer diameter side) than the previously wound winding. Since the surface of the insulating film of the conductor is slippery, there is a possibility that the previously wound winding may be pushed out to the other end side (inner diameter side) of the stator core (hereinafter also referred to as "winding disorder"). The inventors of the present invention have discovered that winding disorder may occur. When winding disorder occurs, there is a risk that the conductor forming the winding pulled so as to be pushed out to the inner diameter side end may break, or the cross-sectional area of the pulled conductor may become smaller and the electrical resistance may increase, and the amount of heat generation of the conductor may increase. That is, the reliability of the conductor wound in the first layer of the winding part may decrease. Note that this phenomenon is not limited to the case where the winding direction of the first layer of the winding part is such that the conductor is wound from the outer diameter side to the inner diameter side in the radial direction of the stator core, and the same may occur when the winding direction of the first layer of the winding part is such that the conductor is wound from the inner diameter side to the outer diameter side in the radial direction of the stator core.

[0006] On the other hand, as a slip prevention of the conductor wound in the first layer of the winding part, there is a structure in which a groove or the like is provided in the winding cylinder part of the insulator (Patent Document 2, Patent Document 3). However, in this structure, since a groove or the like adapted to the outer diameter of the conductor is provided in the winding cylinder part, it is necessary to change the insulator according to the outer diameter of the conductor, and there is a problem that the manufacturing cost of the electric motor increases.

[0007] The disclosed technology has been made in view of the above, and an object is to provide a method for manufacturing an electric motor and an electric motor that can avoid an increase in the manufacturing cost of the electric motor and can improve the reliability of the conductor wound in the first layer of the winding part.

Means for Solving the Problems

[0008] One aspect of the method for manufacturing an electric motor disclosed in the present application is a method for manufacturing an electric motor including a stator core having an annular yoke portion and teeth portions extending radially from the yoke portion in the radial direction of the yoke portion, an insulator having a winding cylinder portion attached to the teeth portions, and a winding portion in which a plurality of layers are formed by windings in which a conducting wire is wound around the winding cylinder portion and the teeth portions. When the winding pitch of the conducting wires wound side by side in the radial direction is P and the outer diameter of the conducting wire is B, in the radial direction, the conducting wire is wound around the first layer of the winding portion so as to satisfy P > B, and the conducting wire is wound around at least one layer after the second layer of the winding portion so as to satisfy P ≤ B.

Effect of the Invention

[0009] According to one aspect of the method for manufacturing an electric motor disclosed in the present application, an increase in the manufacturing cost of the electric motor can be avoided, and the reliability of the conducting wire wound around the first layer of the winding portion can be improved.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

BEST MODE FOR CARRYING OUT THE INVENTION

[0011] Hereinafter, the method for manufacturing an electric motor and an example of the electric motor disclosed in the present application will be described in detail with reference to the drawings. Note that the method for manufacturing an electric motor and the electric motor disclosed in the present application are not limited by the following examples.

EXAMPLE

[0012] (Compressor) FIG. 1 is a longitudinal sectional view showing a compressor including an electric motor according to an embodiment. As shown in FIG. 1, the compressor 1 is a so-called rotary compressor and includes a container 2, a shaft 3, a compression section 5, and an electric motor 6. The container 2 is formed of a metallic material and forms a sealed internal space 7. The internal space 7 is generally formed in a columnar shape. The container 2 is formed such that the central axis of the internal space 7 is parallel to the vertical direction when the container 2 is vertically placed on a horizontal plane. An oil sump 8 is formed at the lower part of the internal space 7 in the container 2. Lubricating oil for lubricating the compression section 5 is stored in the oil sump 8. A suction pipe 11 for sucking refrigerant and a discharge pipe 12 for discharging the compressed refrigerant are connected to the container 2. The shaft 3 is provided along the vertical direction and is disposed in the internal space 7 of the container 2 such that one end is immersed in the oil sump 8. The shaft 3 is supported by the container 2 rotatably about the central axis of the internal space 7. By rotating, the shaft 3 supplies the lubricating oil stored in the oil sump 8 to the compression section 5.

[0013] The compression section 5 is disposed at the lower part in the internal space 7 and above the oil sump 8. The compressor 1 further includes an upper muffler cover 14 and a lower muffler cover 15. The upper muffler cover 14 is disposed above the compression section 5 in the internal space 7. The upper muffler cover 14 forms an upper muffler chamber 16 inside thereof. The lower muffler cover 15 is provided at the lower part of the compression section 5 in the internal space 7 and above the oil sump 8. A lower muffler chamber 17 is formed inside the lower muffler cover 15. The lower muffler chamber 17 communicates with the upper muffler chamber 16 through a communication passage (not shown) formed in the compression section 5. A discharge hole 18 for discharging the compressed refrigerant is formed between the upper muffler cover 14 and the shaft 3, and the upper muffler chamber 16 communicates with the internal space 7 through the discharge hole 18.

[0014] The compression section 5 compresses the refrigerant supplied from the suction pipe 11 when the shaft 3 driven by the electric motor 6 rotates, and supplies the compressed refrigerant to the upper muffler chamber 16 and the lower muffler chamber 17. The refrigerant is compatible with the lubricating oil.

[0015] (Electric motor) The electric motor 6 is disposed above the compression part 5 in the internal space 7. The electric motor 6 is a three-phase electric motor and includes a rotor 21 and a stator 22. The rotor 21 is fixed to the shaft 3. The stator 22 is generally formed in a cylindrical shape, is disposed so as to surround the rotor 21 on the outer peripheral side of the rotor 21, and is fixed to the container 2. The stator 22 includes a stator core 23, a lower insulator 25B as a first insulator, an upper insulator 25A as a second insulator, and a plurality of windings 46.

[0016] The upper insulator 25A is attached to the upper end portion of the stator core 23 in the axial direction of the shaft 3. The lower insulator 25B is attached to the lower end portion of the stator core 23 in the axial direction of the shaft 3. The upper insulator 25A and the lower insulator 25B are an example of an insulating portion that insulates the stator core 23 and the windings 46. In the present embodiment, the upper insulator 25A and the lower insulator 25B are formed in the same shape, and are used as the upper insulator 25A when provided at the upper end portion of the stator core 23, and are used as the lower insulator 25B when provided at the lower end portion of the stator core 23. Hereinafter, in the embodiment, the insulator 25 including the upper insulator 25A and the lower insulator 25B is referred to as the insulator 25. Note that, in the present embodiment, the case where the upper insulator 25A and the lower insulator 25B have the same shape is illustrated, but the upper insulator 25A and the lower insulator 25B may be formed in different shapes from each other.

[0017] FIG. 2 is a bottom view showing the stator core 23 in the embodiment. As shown in FIG. 2, the stator core 23 is formed by laminating a plurality of metal plates made of a soft magnetic material such as a silicon steel sheet (electromagnetic steel sheet), and includes a yoke portion 31 and a plurality of stator core teeth portions 32 (32-1 to 32-9). The yoke portion 31 is generally formed in an annular shape (cylindrical shape). The first stator core tooth portion 32-1 among the plurality of stator core tooth portions 32-1 to 32-9 is formed in a generally columnar shape extending in the radial direction of the stator core 23. One end of the first stator core tooth portion 32-1 is connected to the inner peripheral surface of the yoke portion 31, that is, it extends from the inner peripheral surface of the yoke portion 31 to the inside in the radial direction of the yoke portion 31. The stator core tooth portions 32-2 to 32-9 different from the first stator core tooth portion 32-1 among the plurality of stator core tooth portions 32-1 to 32-9 are also formed in a generally columnar shape in the same manner as the first stator core tooth portion 32-1, and extend from the inner peripheral surface of the yoke portion 31 to the inside in the radial direction of the yoke portion 31. The plurality of stator core tooth portions 32-1 to 32-9 are formed to be arranged at equal intervals of 40° in the circumferential direction of the yoke portion 31 on the inner peripheral surface of the yoke portion 31 in the case of the 9-slot stator 22.

[0018] FIG. 3 is a perspective view schematically showing the insulator 25 in the embodiment. As shown in FIG. 3, the insulator 25 (upper insulator 25A and lower insulator 25B) is formed in a ring shape by an insulator exemplified by polybutylene terephthalate resin (PBT). As shown in FIG. 3, the insulator 25 has an outer peripheral wall portion 41, a plurality of insulator teeth portions 42 (42-1 to 42-9) which are winding portions around which a conductor (winding 46) is wound, and a plurality of flange portions 43 (43-1 to 43-9). The outer peripheral wall portion 41 is generally formed in a cylindrical shape. A plurality of slits 44 extending along the central axis of the outer peripheral wall portion 41 are formed at intervals in the circumferential direction of the outer peripheral wall portion 41 from one end in the direction along the central axis of the outer peripheral wall portion 41 (axial direction of the shaft 3). Further, the other end of the outer peripheral wall portion 41 in the direction along the central axis of the outer peripheral wall portion 41 is in contact with the stator core 23. In other words, the plurality of slits 44 are formed to extend from one end of the outer peripheral wall portion 41 on the side opposite to the stator core 23 toward the stator core 23 side. By passing the winding 46 (conductor) drawn out from the winding portion 45 described later through each slit 44, the winding 46 drawn out from the inner peripheral side to the outer peripheral side of the outer peripheral wall portion 41 forms a cross wire 49 stretched along the outer peripheral surface of the outer peripheral wall portion 41. In the insulator 25 shown in FIG. 3, the shape and arrangement of each slit 44 of the outer peripheral wall portion 41 are schematically shown, and the details of the shape and arrangement of each slit 44 will be described later.

[0019] Of the plurality of insulator teeth portions 42-1 to 42-9, the first insulator tooth portion 42-1 is formed in a straight columnar shape with a substantially semicircular cross section. One end of the first insulator tooth portion 42-1 is connected to the inner peripheral surface of the outer peripheral wall portion 41, that is, it extends from the inner peripheral surface of the outer peripheral wall portion 41 radially inward of the outer peripheral wall portion 41. Insulator tooth portions 42-2 to 42-9 different from the first insulator tooth portion 42-1 among the plurality of insulator tooth portions 42-1 to 42-9 are also formed in a straight columnar shape with a substantially semicircular cross section, similar to the first insulator tooth portion 42-1, and extend from the inner peripheral surface of the outer peripheral wall portion 41 radially inward of the outer peripheral wall portion 41. The plurality of insulator tooth portions 42-1 to 42-9 are arranged on the inner peripheral surface of the outer peripheral wall portion 41 at equal intervals of 40 degrees with respect to the circumferential direction of the outer peripheral wall portion 41. Note that the insulator tooth portion 42 in the embodiment is not limited to a shape that is a straight columnar shape with a substantially semicircular cross section, and may be formed, for example, in a straight columnar shape with a substantially polygonal cross section.

[0020] The plurality of flange portions 43-1 to 43-9 correspond to the plurality of insulator tooth portions 42-1 to 42-9 and are each formed in a substantially semicircular plate shape. The first flange portion 43-1 corresponding to the first insulator tooth portion 42-1 among the plurality of flange portions 43-1 to 43-9 is continuously formed integrally with the first insulator tooth portion 42-1 at the other end of the first insulator tooth portion 42-1. Flange portions 43 different from the first flange portion 43-1 among the plurality of flange portions 43-1 to 43-9 are also formed integrally with each of the insulator tooth portions 42-1 to 42-9 continuously at the other ends of the plurality of insulator tooth portions 42-1 to 42-9, similar to the first flange portion 43-1.

[0021] FIG. 4 is a bottom view showing the stator 22 in the embodiment, and is a view of the stator 22 as seen from the lower insulator 25B side. As shown in FIG. 4, in each of the plurality of stator core teeth portions 32-1 to 32-9 of the stator core 23, a plurality of windings 46 (U-phase windings 46-U1 to 46-U3, V-phase windings 46-V1 to 46-V3, W-phase windings 46-W1 to 46-W3, which will be described later) are wound respectively. As shown in FIG. 4, winding portions 45 are respectively formed in each of the stator core teeth portions 32-1 to 32-9 by the windings 46 of each phase. In each winding portion 45, a plurality of layers, for example, about 6 to 8 layers, are formed by the windings 46 in which the conductor is wound around the stator core teeth portion 32 via the insulator teeth portion 42. Each winding portion 45 forming 9 slots is indicated by attaching symbols 1 to 9 in the clockwise order in FIG. 4. The 9 winding portions 45 are arranged along the circumferential direction of the stator core 23 such that the three phases repeat the same order. That is, they are arranged to repeat the U-phase, V-phase, and W-phase in the clockwise order of FIG. 4.

[0022] The motor 6 in the embodiment is a 6-pole 9-slot concentrated winding type motor. The plurality of windings (conductors) 46 include a plurality of U-phase windings 46-U1 to 46-U3 forming the U-phase winding portion 45, a plurality of V-phase windings 46-V1 to 46-V3 forming the V-phase winding portion 45, and a plurality of W-phase windings 46-W1 to 46-W3 forming the W-phase winding portion 45.

[0023] Note that although the motor 6 in the embodiment is configured with 9 slots, the number of slots, that is, the number of winding portions 45 (or the number of stator core teeth portions 32) is not limited.

[0024] In addition, although the stator core 23 in the embodiment has an annular yoke portion 31 integrally formed, the yoke portion may be formed by connecting a plurality of arc-shaped yoke components (not shown) and assembling them in an annular shape. Further, although the stator core teeth portion 32 of the stator core 23 in the embodiment extends radially inward from the inner peripheral surface of the yoke portion 31, it may extend radially outward from the outer peripheral surface of the yoke portion 31. Similarly, the insulator teeth portion 42 of the insulator 25 is not limited to a shape that extends radially inward from the inner peripheral surface of the outer peripheral wall portion 41, and may extend radially outward from the outer peripheral surface of the outer peripheral wall portion 41. Further, the insulator teeth portion 42 in the embodiment is not limited to a shape that is a straight columnar body with a substantially semicircular cross section, and may be formed, for example, in a straight columnar body shape with a substantially polygonal cross section.

[0025] (Characteristic structure of the motor) Next, the characteristic structure of the motor 6 of this embodiment will be described. The characteristics of this embodiment include the winding state of the winding 46 of the first layer 1L of the winding portion 45.

[0026] FIG. 5 is a cross-sectional view schematically showing the winding portion (coil) 45 in the motor 6 of the embodiment. In FIG. 5, the numbers "1 to 8" attached to the windings 46 (conductors) of each layer of the winding portion 45 indicate the first layer 1L to the eighth layer 8L.

[0027] As shown in Fig. 5, in the embodiment, the winding portion 45 is wound at a predetermined winding pitch P (the amount of movement of the nozzle N in the radial direction Y per turn) for each layer of the winding portion 45 so as to be arranged in the radial direction Y of the yoke portion 31 (which also corresponds to the radial direction Y of the outer peripheral wall portion 41. Hereinafter, it is also simply referred to as the radial direction Y). The winding 46 wound as the first layer 1L of the winding portion 45 is wound so as to be in contact with the surface on which the conducting wire is wound in the insulator teeth portion 42 (hereinafter referred to as the surface of the insulator teeth portion 42). When the winding pitch of the conducting wire (winding 46) in one layer of the winding portion 45 is P and the outer diameter of the conducting wire is B, in the radial direction Y, the winding pitch P of the winding 46 (conducting wire) wound as the first layer 1L satisfies P > B. Further, in the winding portion 45, the winding pitch P of the winding 46 (conducting wire) wound as at least one layer after the second layer 2L satisfies P ≤ B. By winding the winding 46 at such a winding pitch P, the winding 46 of the first layer 1L is not disturbed, and the occupation ratio of the winding portion 45 is increased. Details of this will be described later (see the description of the method for manufacturing the electric motor).

[0028] Here, the winding pitch P refers to the amount of movement of the nozzle N in the radial direction Y per turn (one round) of the conducting wire (winding 46) wound around the insulator teeth portion 42 and the stator core teeth portion 32 in the radial direction Y, and is different from the pitch dimension between the windings 46 adjacent to each other in the radial direction Y. For the sake of convenience, in the drawings, the winding pitch P is also shown like the pitch dimension, but in the following description, the winding pitch P refers to the amount of movement of the nozzle N. Note that the amount of movement of the nozzle N refers to the amount of change in the relative position between the nozzle N and the insulator teeth portion 42. That is, when changing the relative position of the nozzle N with respect to the insulator teeth portion 42, the insulator teeth portion 42 side may be fixed and the nozzle N side may move, the nozzle N side may be fixed and the insulator teeth portion 42 side may move, or both the insulator teeth portion 42 side and the nozzle N side may move.

[0029] In the embodiment, as an example, the outer diameter B of the conducting wire and the winding pitch P of the first layer 1L and the second layer 2L satisfy P > B, and the winding pitch P from the third layer 3L to the eighth layer 8L satisfies P ≤ B. In other words, in the first layer 1L and the second layer 2L of the winding part 45, it is wound so that a gap G is formed between adjacent winding wires 46 in the radial direction Y, and in the third layer 3L and subsequent layers, the adjacent winding wires 46 in the radial direction Y are wound so as to be in close contact with each other.

[0030] (Method for manufacturing an electric motor) The method for manufacturing an electric motor according to the embodiment includes a winding step of winding a conducting wire around the stator core tooth part 32 through the insulator tooth part 42 to form a winding part (coil) 45. As shown in FIG. 5, in the winding step of the embodiment, the conducting wire is wound using a winding machine (not shown) having a nozzle N for supplying the conducting wire. The characteristics of the method for manufacturing an electric motor according to the present embodiment include controlling, by the control unit C of the winding machine, the movement amount (winding pitch P) of the nozzle N that supplies the conducting wire wound around the first layer 1L of the winding part 45 in the winding step.

[0031] In the winding step, the conducting wire is supplied from the nozzle N that moves in the radial direction Y of the stator core 23, and the winding wire 46 is wound on the stator core tooth part 32 of the stator core 23 and the insulator tooth part 42 of the insulator 25 attached on top of the stator core tooth part 32, and the lead wire 49 drawn out from the winding part 45 is wound along the outer peripheral wall part 41 of the insulator 25. In the embodiment, when forming each three-phase winding part 45 using a winding machine, for example, when forming the winding part 45 for each phase using three nozzles N and forming the winding parts 45 of each phase in order, the so-called three-nozzle winding method for forming the three-phase winding parts 45 is applied.

[0032] (Comparative example) First, in order to compare with the winding process in the manufacturing method of the motor of the embodiment, the winding process in the manufacturing method of the motor of the comparative example will be described. In the winding process in the comparison, in order to increase the occupation ratio of the winding part, when the outer diameter of the conductor wire in the state before being wound is B and the winding pitch (the amount of movement of the nozzle N in the radial direction Y per turn) of the winding wire of the first layer 1L of the winding part is P, the conductor wire is wound so as to satisfy P < B (for example, P = 0.8B). Note that the outer diameter B of the conductor wire tends to be slightly reduced in the outer diameter of the winding wire wound around the winding part because the conductor wire is stretched in the longitudinal direction by the tension applied when the conductor wire is wound around the stator core tooth part 32 through the insulator tooth part 42.

[0033] FIG. 6 is a cross-sectional view schematically showing a winding part 145 in the motor of the comparative example. In FIG. 6, the numbers "1 to 8" attached to the winding wires 46 of each layer of the winding part 145 indicate the first layer 1L to the eighth layer 8L. As shown in FIG. 6, in the winding part 145 of the comparative example, for example, the winding wire 46 forms 8 layers, and the conductor wire is wound so that the winding pitch P of all layers from the first layer 1L to the eighth layer 8L satisfies P < B. For this reason, the first layer 1L to the eighth layer 8L of the winding part 145 are wound so that the adjacent winding wires 46 are in close contact with each other in the radial direction Y.

[0034] (Winding process of the comparative example) FIG. 7 is a cross-sectional view for explaining a winding part when the winding wire of the first layer 1L is normally wound in the winding process of the comparative example. As shown in FIG. 7, in the comparative example, in the first layer 1L, the winding wire 46 of the second turn 2T slides down the outer peripheral surface of the winding wire 46 of the first turn 1T to the other end side in the radial direction Y (the inner diameter side which is the inner side in the radial direction Y), and then, following the winding wire 46 of the first turn 1T, the winding wire 46 of the second turn 2T and the winding wire 46 of the third turn 3T are wound in sequence so as to be adjacent to and in contact with each other. Also, after the fourth turn 4T and later, since the winding pitch P satisfies P < B, the conductor wire is wound so that the adjacent winding wires 46 are aligned in contact with each other with respect to the radial direction Y. That is, when each winding wire 46 (conductor wire) forming the first layer 1L is normally wound, each winding wire 46 of the first layer 1L is wound densely without gaps.

[0035] FIG. 8 is a cross-sectional view for explaining the case where the winding position of the winding 46 of the first layer 1L is displaced in the winding process of the comparative example. FIG. 9 is a side view for explaining the case where the winding position of the winding 46 is displaced in the winding process of the comparative example.

[0036] As shown in FIG. 8, in the winding process of the comparative example, in the first layer 1L wound on the insulator teeth portion 42, for example, the winding 46 of the second turn 2T wound following the winding 46 of the first turn 1T slides from the position adjacent to and in contact with the winding 46 of the first turn 1T to the other end side in the radial direction Y (the inner diameter side which is the inner side in the radial direction Y), and the winding position of the winding 46 of the second turn 2T may be greatly separated from the winding 46 of the first turn 1T.

[0037] At this time, in the comparative example, since the winding pitch (the amount of movement of the nozzle N in the radial direction Y per turn) P is P < B (P = 0.8B), the winding 46 of the third turn 3T is sent by 0.8B from the winding position where the winding 46 of the second turn 2T would normally be wound. For this reason, the winding 46 of the third turn 3T cannot overcome the winding 46 of the second turn 2T toward the other end side in the radial direction Y (the inner diameter side which is the inner side in the radial direction Y), and is wound on the side of the winding 46 of the first turn 1T (the outer diameter side which is one end side in the radial direction Y) rather than the position of the winding 46 of the second turn 2T. As a result, the winding 46 of the third turn 3T enters between the winding 46 of the first turn 1T and the winding 46 of the second turn 2T, and a part of the winding 46 of the third turn 3T rides on and is wound on the winding 46 of the second turn 2T, resulting in winding disorder.

[0038] Subsequently, from the winding position of the winding 46 of the second turn 2T which is originally located at the winding position where the winding 46 of the third turn 3T would be normally wound, the winding 46 of the fourth turn 4T is sent by 0.8B which is smaller than the outer diameter B of the conductor in the state before being wound. As a result, the winding 46 of the fourth turn 4T is wound adjacent to the winding 46 of the second turn 2T on the side opposite to the side of the winding 46 of the third turn 3T in the radial direction Y.

[0039] Also, as shown in FIG. 9, for example, when the windings 46 of the third turn 3T and the fourth turn 4T are inserted between the winding 46 of the first turn 1T and the winding 46 of the second turn 2T, the winding 46 of the second turn 2T continues to be displaced in the direction away from the winding 46 of the first turn 1T in the radial direction Y (the direction approaching the flange portion 43), resulting in winding disorder. In particular, the winding 46 of the second turn 2T is pulled to the other end side in the radial direction Y (the inner diameter side which is the inner side in the radial direction Y), the cross-sectional area decreases, the electrical resistance increases, and the problem of increased heat generation of the winding 46 occurs. Further, when winding disorder occurs in the first layer 1L, the conductor wound around the second layer 2L rides on the winding 46 causing the winding disorder, resulting in a problem that the winding portion 45 bulges significantly in the stacking direction (the winding diameter direction, for example, the axial direction of the shaft 3), and the winding portion 45 is distorted and enlarged.

[0040] As described above, in order to increase the occupancy ratio of the winding portion 145, when the winding pitch P of the winding 46 (conductor) wound around the first layer 1L satisfies P < B and the conductor is wound, there is a problem that winding disorder is likely to occur in the winding 46 wound around the first layer 1L. Here, as an example, the case where the winding disorder starts when the winding 46 of the second turn 2T in the first layer 1L slides on the insulator tooth portion 42 is shown. However, in the first layer 1L where the winding 46 is wound in contact with the surface of the insulator tooth portion 42, similar winding disorder may occur at any position in the radial direction Y.

[0041] (Winding Process of the Embodiment) FIG. 10 is a flowchart for explaining the winding process in the method of manufacturing the electric motor of the embodiment. In the winding process of the comparative example described above, the winding pitch P in the first layer 1L of the winding portion 45 is P < B (P = 0.8B), whereas in the winding process of the embodiment, as shown in FIG. 10, the conductor is wound so that the winding pitch P in the first layer 1L of the winding portion 45 satisfies P > B (step S1). When winding the conductor on the first layer 1L, the nozzle N moves along the radial direction Y from the outer peripheral wall portion 41 side as one end side in the radial direction Y of the insulator tooth portion 42 toward the flange portion 43 side as the other end side in the radial direction Y. The winding pitch P, which is the moving amount of the nozzle N, is controlled by the control unit C of the winding machine.

[0042] Subsequently, in the winding process of the embodiment, the conductor is wound on the second layer L2 of the winding portion 45 so that the winding pitch P satisfies P > B (step S2). When winding the conductor on the second layer 2L, the nozzle N moves along the radial direction Y from the flange portion 43 side as the other end side in the radial direction Y of the insulator tooth portion 42 toward the outer peripheral wall portion 41 side as one end side in the radial direction Y.

[0043] Next, in the winding process of the embodiment, the conductor is wound on the third layer L3 of the winding portion 45 so that the winding pitch P satisfies P ≤ B (step S3). When winding the conductor on the third layer 3L, the nozzle N moves along the radial direction Y from the outer peripheral wall portion 41 side (one end side in the radial direction Y) of the insulator tooth portion 42 toward the flange portion 43 side (the other end side in the radial direction Y). In the winding process of the embodiment, the conductor is also wound on the fourth layer 4L and subsequent layers of the winding portion 45 so that the winding pitch P satisfies P ≤ B (step S4).

[0044] As described above, the nozzle N winds the conductive wire while reciprocating in the radial direction Y. That is, the nozzle N winds the conductive wire on the first layer 1L on the forward stroke of the reciprocating movement, winds the conductive wire on the second layer 2L on the return stroke of the reciprocating movement, and winds it while repeating the reciprocating movement a predetermined number of times from the third layer 3L onward. Further, in the winding process of the embodiment, as the nozzle N moves, the stator core 23 and the insulator 25 are rotated around the radial direction Y, so that the conductive wire is wound around the stator core teeth portion 32 through the insulator teeth portion 42. Note that the direction in which the winding wire 46 is wound with respect to the radial direction Y in the first layer 1L, that is, the moving direction of the nozzle N in the first layer 1L is not limited to the direction from the outer peripheral wall portion 41 side toward the flange portion 43 side, and may be the direction from the flange portion 43 side toward the outer peripheral wall portion 41 side.

[0045] FIG. 11 is a cross-sectional view for explaining the case where the winding wire 46 of the first layer 1L is normally wound in the winding process of the embodiment. As shown in FIG. 11, in the winding process of the embodiment, in the first layer 1L, following the winding wire 46 of the first turn 1T, the winding wire 46 of the second turn 2T and the winding wire 46 of the third turn 3T are successively wound with a gap G therebetween. Also, from the fourth turn 4T onward, by winding the conductive wire so that the winding pitch P satisfies P>B, the winding wires 46 are wound in alignment while leaving a gap G between the adjacent winding wires 46 with respect to the radial direction Y.

[0046] FIG. 12 is a cross-sectional view for explaining the case where the winding position of the winding wire 46 of the first layer 1L is shifted in the winding process of the embodiment. As shown in FIG. 12, also in the winding process of the embodiment, similar to the winding process of the above-described comparative example (see FIG. 8), in the first layer 1L, for example, the winding wire 46 of the second turn 2T wound following the winding wire 46 of the first turn 1T may slide on the insulator teeth portion 42 in the radial direction Y from the winding position where the winding wire 46 of the second turn 2T is normally wound, and the winding position of the winding wire 46 of the second turn 2T may be separated from the winding wire 46 of the first turn 1T.

[0047] Even in such a case, in the winding process of the embodiment, the conductor is wound such that the winding pitch P of the first layer 1L satisfies P > B. As a result, the movement amount of the nozzle N is appropriately ensured. Therefore, the winding 46 of the third turn 3T can smoothly overcome the winding 46 of the second turn 2T with a shifted winding position. The winding 46 of the third turn 3T is wound around the surface of the insulator teeth portion 42 while being in contact with the flange portion 43 side of the outer peripheral surface of the winding 46 of the second turn 2T, for example. For this reason, the winding 46 of the third turn 3T is appropriately wound on the side opposite to the winding 46 of the first turn 1T with respect to the winding 46 of the second turn 2T without entering between the winding 46 of the first turn 1T and the winding 46 of the second turn 2T as in the above-described comparative example.

[0048] In other words, the winding pitch P (the movement amount of the nozzle N) of the first layer 1L is preferably set to a value obtained by adding a predetermined value corresponding to the maximum value of the displacement amount of the winding position of the assumed winding 46 in the first layer 1L, that is, the maximum value of the slipping amount of the winding 46, to the outer diameter B (the upper limit value of the dimensional tolerance) of the conductor. Note that the winding pitch P of the first layer 1L may be set to a value equal to or greater than the value at which the next winding 46 is wound so as to be in contact with the outer peripheral surface (the flange portion 43 side of the outer peripheral surface) of the winding 46 with a shifted winding position. Thereby, in the winding process of the embodiment, it becomes possible for the next winding 46 to overcome the winding 46 with a shifted winding position. For this reason, in the winding process of the embodiment, the order of the windings 46 of each turn wound in the first layer 1L is not disrupted, and the order of the windings 46 of each turn is correctly wound, so that it is possible to prevent winding disorder from occurring in the first layer 1L.

[0049] Even in the windings 46 after the fourth turn 4T and later, even when the winding position of the previously wound winding 46 is shifted, since the previously wound winding 46 is wound while the next winding 46 smoothly overcomes it, it is possible to prevent winding disorder from occurring in the first layer 1L.

[0050] As described above, in the winding process of the embodiment, the winding pitch P of the first layer 1L winds the conducting wire so that P > B, thereby preventing winding disorder in the winding 46 of the first layer 1L. At the same time, the winding pitch P of at least one layer after the second layer 2L winds the conducting wire so that P ≤ B, thereby increasing the occupation ratio of the winding portion 45. In the embodiment, the outer diameter B of the conducting wire in the state before being wound and the winding pitch P of the third layer 3L and subsequent layers of the winding portion 45 satisfy P ≤ B. It should be noted that it is preferable that the winding pitch P of all layers after the second layer 2L satisfies P ≤ B, which can achieve both preventing winding disorder in the first layer L1 and maximizing the occupation ratio of the winding portion 45. The outer diameter B of the conducting wire in the state before being wound can be approximated to the outer diameter of the conducting wire in the bridging wire 49 extending from the winding portion 45 to the outer peripheral wall portion 41, as will be described later. Therefore, in this embodiment, the outer diameter of the conducting wire in the bridging wire 49 extending from the winding portion 45 to the outer peripheral wall portion 41 is treated as the outer diameter B of the conducting wire in the state before being wound.

[0051] It should be noted that this embodiment is not limited to the winding pitch P of all layers after the second layer 2L satisfying P ≤ B. In the second layer 2L and subsequent layers, a layer with a winding pitch P satisfying P > B may be included. Also, when the winding pitch P of all layers after the second layer 2L satisfies P ≤ B, the winding pitch P of each layer after the second layer 2L may be made different. For example, in the second layer 2L and subsequent layers, the winding pitch P of each layer may be increased or decreased, or the winding pitch P may be made different only for an arbitrary layer.

[0052] Also, in the winding process of the embodiment, in the first layer 1L of the winding portion 45, it is preferable to wind the conducting wire so that the outer diameter B of the conducting wire and the winding pitch P satisfy P > 1.02B. In other words, for the winding 46 wound on the first layer 1L of the winding portion 45, it is preferable that the outer diameter B of the conducting wire and the winding pitch P in the state before being wound satisfy P > 1.02B. Thereby, in the winding process of the embodiment, when winding the conducting wire on the first layer 1L, the previously wound winding 46 can be appropriately sent in the radial direction Y so that the subsequently wound conducting wire can surely overcome it. As a result, in the winding process, winding disorder in the first layer 1L can be further prevented.

[0053] In the winding process of the embodiment, in the first layer 1l of the winding part 45, it is preferable to wind the conducting wire so that the outer diameter B of the conducting wire and the winding pitch P satisfy 2B > P. In other words, for the winding 46 wound on the first layer 1L of the winding part 45, it is preferable that the outer diameter B of the conducting wire and the winding pitch P in the state before winding satisfy 2B > P. Thereby, in the first layer 1L, it is possible to prevent winding disorder and avoid a decrease in the number of turns (winding times) of the winding 46 accompanying an increase in the winding pitch P. When the winding pitch P of the winding 46 in the first layer 1L is set to 2B or more, in order to compensate for the decrease in the number of turns in the first layer 1L and ensure an appropriate occupation ratio, the number of turns of the winding 46 in the second layer 2L and subsequent layers (in the embodiment, the third layer 3L and subsequent layers) needs to be greatly increased. In this case, in the second layer 2L and subsequent layers, there is a risk that swelling occurs in the stacking direction (winding diameter direction) of the winding 46, or the number of layers forming the winding part 45 increases, resulting in a decrease in the alignment of the winding 46. Further, even when the winding position of the winding 46 wound first in the first layer 1L of the winding part 45 is displaced, the amount of displacement hardly exceeds the outer diameter B of the conducting wire. Therefore, the winding process of the embodiment ensures the reliability of the winding state of the winding 46 and suppresses a decrease in the alignment of the winding 46 in the winding part 45 by winding the conducting wire so as to satisfy 2B > P as described above.

[0054] In the winding process of the embodiment, in at least one layer after the second layer 2L (in the embodiment, after the third layer 3L), it is preferable to wind the conductor wire such that the outer diameter B of the conductor wire in the state before winding and the winding pitch P satisfy 0.82B ≤ P ≤ B. In other words, in the winding portion 45, for the winding wire 46 wound around at least one layer after the second layer 2L (in the embodiment, after the third layer 3L), it is preferable that the outer diameter B of the conductor wire in the state before winding and the winding pitch P satisfy 0.82B ≤ P ≤ B. Different from the winding wire 46 of the first layer 1L in contact with the surface of the insulator teeth portion 42, the winding wire 46 wound after the second layer 2L is wound on top of the winding wire 46 wound around the layer immediately below it, so its movement is restricted and it is not easy to slip, thus suppressing winding disorder. Therefore, after the second layer 2L, the winding pitch P satisfies 0.82B ≤ P ≤ B. For example, by making it as small as the outer diameter of the conductor 46a (see FIG. 5) in the conductor wire, the occupation ratio of the winding portion 45 can be increased. On the other hand, if the winding pitch P becomes smaller than 0.82B, there is a possibility that the winding wire 46 to be wound next cannot overcome the previously wound winding wire 46, and as a result, there is a possibility that the layers after the second layer 2L cannot be properly formed, which is not preferable.

[0055] Note that the relational expression regarding the outer diameter B of the conductor wire (for example, "the winding pitch P of the first layer 1L satisfies P > B") preferably holds even when this outer diameter B is the upper limit value (maximum finished outer diameter) of the dimensional tolerance of the outer diameter of the conductor wire, so that the winding pitch P can be optimally set, and the action of preventing winding disorder of the winding wire 46 wound around the first layer 1L can be most appropriately obtained.

[0056] As shown in FIG. 5, the conductor wire (winding wire 46) has a conductor 46a and an insulating film 46b covering the conductor 46a, and the outer diameter B of the conductor wire is a dimension including the thickness of the insulating film 46b. In the embodiment, for the conductor wire, for example, the outer diameter of the conductor 46a is 0.8 mm, and the upper limit value of the dimensional tolerance of the outer diameter B of the conductor wire covered with the insulating film 46b is set to 0.88 mm.

[0057] The insulating film 46b contains, for example, polyamideimide, and the static friction coefficient of the insulating film 46b is 0.12 or less. The insulating film 46b in the embodiment has high lubricity, and the static friction coefficient is about 0.05. The conductor (coil 46) with a small static friction coefficient on the surface of the insulating film 46b can suppress the snagging of the conductor in the winding process, but it is easy to slip in the first layer 1L in contact with the surface of the insulator teeth portion 42, and the winding position of the coil 46 is likely to shift. Therefore, when using a conductor with a small static friction coefficient of the insulating film 46b as described above, by satisfying P > B for the winding pitch P of the first layer 1L as in the embodiment, the effect of preventing the winding disorder of the first layer 1L is high.

[0058] Also, 15% by weight or more and 45% by weight or less of glass fiber is added to the insulator 25, and the dynamic friction coefficient of the surface of the insulator teeth portion 42 is increased. When the addition amount is less than 15% by weight, the molding shrinkage rate of the resin material containing glass fiber increases, and the moldability of the insulator 25 decreases, which is not preferable. When the addition amount exceeds 45% by weight, the increase in the effect of increasing the dynamic friction coefficient is poor, and only the manufacturing cost increases, which is not preferable. By adding glass fiber in this way, the insulator 25 can prevent the coil 46 wound around the surface of the insulator teeth portion 42 from slipping, so that the effect of preventing the winding disorder of the first layer 1LL and the reliability of the conductor wound around the first layer 1L can be improved.

[0059] Also, the conductor (coil 46) has a tensile strength of less than 460 [N / mm 2 , and for example, a soft copper wire is used. A conductor with such a low tensile strength is likely to be stretched by the tension applied when being wound, and the reliability of the conductor decreases (for example, when the conductor is stretched and the cross-sectional area of the conductor decreases, the amount of heat generation increases. Also, if the conductor is stretched and finally breaks, no current flows through the coil and the motor stops operating). Therefore, when using a conductor with a low tensile strength as in the embodiment, by satisfying P > B for the winding pitch P of the first layer 1L, the effect of preventing the winding disorder of the first layer 1L and preventing the reliability of the conductor from decreasing is particularly high.

[0060] Further, for the motor 6 of the embodiment, when the first cross-sectional area orthogonal to the length direction of the winding 46 wound around the first layer 1L is A1 and the second cross-sectional area orthogonal to the length direction of the jumper wire 49 extending from the winding portion 45 to the outer peripheral wall portion 41 is A2 (see FIG. 5), (A1 / A2)>0.85 is satisfied. By satisfying (A1 / A2)>0.85, the elongation rate (the ratio at which the conductor extends from its original length) of the winding 46 wound around the first layer 1L can be suppressed to 15% or less. The first cross-sectional area A1 and the second cross-sectional area A2 include the cross-sectional area of the insulating film 46b. The outer diameter of the jumper wire 49 drawn out from the winding portion 45 is larger than the outer diameter of the conductor in the portion where the winding 46 is formed because elongation due to tension is less likely to occur as in the case of the winding 46, and is close to the outer diameter B of the conductor in the state before being wound. By thus satisfying (A1 / A2)>0.85, the winding 46 of the first layer 1L of the winding portion 45 is wound while being suppressed from extending to such an extent that the increase in the heat generation amount becomes remarkable or there is a risk of breakage.

[0061] As described above, since the jumper wire 49 drawn out from the winding portion 45 is less likely to be elongated by tension as in the case of the winding 46, it is larger than the outer diameter of the conductor in the portion where the winding 46 is formed and is close to the outer diameter B of the conductor in the state before being wound. Therefore, the outer diameter B of the conductor in the state before being wound can be approximated to the outer diameter of the conductor as the jumper wire 49 extending from the winding portion 45 to the outer peripheral wall portion 41. Thus, in this embodiment, the outer diameter of the conductor in the jumper wire 49 extending from the winding portion 45 to the outer peripheral wall portion 41 is treated as the outer diameter B of the conductor in the state before being wound.

[0062] When viewed in the cross-section of the insulator teeth portion 42 along the radial direction Y in the embodiment, the surface of the insulator teeth portion 42 around which the conductor is wound has a flat surface 42a extending along the radial direction Y and an arcuate curved surface 42b as an inclined surface inclined with respect to the flat surface 42a. The flat surface 42a extends from the inner peripheral surface of the outer peripheral wall portion 41. The curved surface 42b is continuously formed from the side surface of the flange portion 43 facing the outer peripheral wall portion 41 to the flat surface 42a.

[0063] When the length of the flat surface 42a in the radial direction Y of the winding portion 45 is M and the number of turns (winding times) of the winding 46 wound around the flat surface 42a in the first layer 1L is T, (B×T) < M is satisfied. That is, it is wound so that a gap G is generated between the windings 46 wound around the flat surface 42a.

[0064] Also, in the winding process of the embodiment, by winding the conducting wire using a winding machine having a nozzle N, the control unit C of the winding machine controls the movement amount (winding pitch P) of the nozzle N, so that a winding portion 45 with a desired winding pitch P and no winding disorder can be easily formed.

[0065] (Modification Examples 1 and 2) In the winding process of the above-described embodiment, the conducting wire was wound so that the winding pitch P of the first layer 1L and the second layer 2L satisfies P > B, but the conducting wire may be wound so that the winding pitch P after the second layer 2L satisfies P ≤ B.

[0066] FIG. 13 is a cross-sectional view showing the winding state of the winding 46 in the winding process of Modification Example 1. FIG. 14 is a cross-sectional view showing the winding state of the winding 46 in the winding process of Modification Example 2. In FIGS. 13 and 14, the numbers "1 to 8" attached to the windings 46 of each layer of the winding portions 55 and 56 indicate the first layer 1L to the eighth layer 8L. In FIG. 14, only the first layer 1L and the second layer 2L are shown.

[0067] In the winding processes of Modification Examples 1 and 2, due to the elongation of the conducting wire caused by the tension applied during winding, the outer diameter of the winding 46, which is the conducting wire in the wound state, is about 0.95 times the outer diameter of the conducting wire in the state before winding. Therefore, the cross-sectional area of the winding 46, which is the conducting wire in the wound state, is about 0.9 times the cross-sectional area of the conducting wire in the state before winding. In this embodiment and the modification examples, the outer diameter of the conducting wire in the state before winding is denoted as B. In the winding process of Modification Example 1, the winding pitch P of the first layer 1L and the second layer 2L of the winding portion 55 is set to 1.1B, and the winding pitch P after the second layer 2L is set to 0.95B. In the winding process of Modification Example 2, the winding pitch P of the first layer 1L of the winding portion 56 is set to 1.4B, and the winding pitch P after the third layer 3L is set to 0.95B.

[0068] As shown in FIG. 13, in the winding process of Modification 1, the winding is aligned such that a minute gap G is formed between adjacent winding wires 46 in the first layer 1L of the winding portion 55, and when wound as the first layer 1L, the conductor is wound without winding disorder in the winding wire 46. On the other hand, when winding the winding wire 46 around the second layer 2L so as to overlap from above the first layer 1L, a part of the winding wire 46 formed as the first layer 1L is pushed aside by the conductor wound as the second layer 2L, so that a part of the winding wire 46 formed as the first layer 1L is displaced to either one side in the radial direction Y, and a portion where a relatively large gap is formed between the winding wires 46 forming the first layer 1L occurs. As a result, a part of the winding wire 46 wound around the second layer 2L enters the relatively large gap between the winding wires 46 in the first layer 1L when overlapping on the first layer 1L, and the winding wires 46 of the second layer 2L and the winding wires 46 of the second layer 2L are arranged side by side at the end of the first layer 1L. As a result of the winding wire 46 of the second layer 2L entering the first layer 1L at the end on the flange portion 43 side of the first layer 1L in this way, a part of the winding wire 46 wound around the third layer 3L enters the second layer 2L and the first layer 1L at the end on the flange portion 43 side. Similarly, on the flange portion 43 side of the winding portion 55, a part of each winding wire 46 of the fourth layer 4L to the eighth layer 8L is also wound so as to sequentially enter the lower layer. Even in such a case, since the winding pitch P of the first layer 1L satisfies P > B, the next winding wire 46 smoothly gets over the winding wire 46 whose winding position has shifted in the first layer 1L and is appropriately wound, so that winding disorder is suppressed when winding the winding wire 46 of the first layer 1L. Further, since the winding pitch P of at least one layer after the second layer 2L is smaller than the winding pitch P of the first layer 1L, a decrease in the occupation ratio of the winding portion 45 is suppressed.

[0069] In the present disclosure, in such a winding state of the winding wire 46, the winding wire 46 of the first layer 1L refers only to the winding wire 46 wound as the first layer 1L, and the winding wire 46 that enters the first layer 1L without overlapping the second layer 2L is included in the winding wire 46 of the second layer 2L. The same applies to the winding wires 46 from the third layer 3L onwards.

[0070] As shown in FIG. 14, in the winding process of Modification 2, the windings 46 are wound in alignment so that a gap G is formed between the windings 46 wound on the first layer 1L of the winding portion 56, and the windings 46 are wound without any winding disorder on the first layer 1L. For this reason, a part of the windings 46 wound on the second layer 2L enters the gap G between the windings 46 wound on the first layer 1L, and the windings 46 of the second layer 2L and the windings 46 of the first layer 1L are arranged side by side on the first layer 1L. As a result of the windings 46 of the second layer 2L entering the first layer 1L in this way, a gap G is formed between the windings 46 wound on the second layer 2L, and the windings 46 wound on the third layer 3L and subsequent layers enter and are wound on the second layer 2L.

[0071] (Effect of the embodiment) As described above, in the method for manufacturing an electric motor according to the embodiment, when the winding pitch of the conductor wound side by side in the radial direction Y of the yoke portion 31 of the stator core 23 is P and the outer diameter of the conductor is B, in the radial direction Y, the conductor is wound on the first layer 1L of the winding portion 45 so as to satisfy P > B, and the conductor is wound on at least one layer after the second layer 2L so as to satisfy P ≤ B. Thereby, even when the winding 46 wound on the first layer 1L slides on the surface of the insulator tooth portion 42, since the winding pitch P of the first layer 1L satisfies P > B, the winding 46 with the shifted winding position can be smoothly overcome by the next winding 46 and properly wound, so that winding disorder on the first layer 1L can be prevented. Further, in the embodiment, by making the winding pitch P of at least one layer after the second layer 2L smaller than the winding pitch P of the first layer 1L, a decrease in the occupation ratio of the winding portion 45 can be suppressed. For this reason, according to the embodiment, for example, it is not necessary to change the insulator having the anti-slip groove of the winding according to the outer diameter of the conductor, and an increase in the manufacturing cost of the electric motor 6 can be avoided. Further, according to the embodiment, since the winding 46 on the first layer 1L of the winding portion 45 can be prevented from stretching due to winding disorder, an increase in the resistance value and the calorific value of the winding 46 can be suppressed, and the reliability of the conductor wound on the first layer 1L can be enhanced.

[0072] Also, in the manufacturing method of the motor of the embodiment, the conducting wire is wound around the first layer 1L so as to satisfy P > 1.02B. Thereby, when winding the conducting wire around the first layer 1L, the previously wound winding 46 can be appropriately sent in the radial direction Y so that the next winding conducting wire can overcome it, so that the occurrence of winding disorder in the first layer 1L can be further prevented.

[0073] Also, in the manufacturing method of the motor of the embodiment, the conducting wire is wound around the first layer 1L so as to satisfy 2B > P. Thereby, in the first layer 1L, while preventing winding disorder, it is possible to avoid a decrease in the number of turns (number of windings) of the winding 46 accompanying an increase in the winding pitch P. In addition, according to the embodiment, while ensuring the reliability of the winding state of the winding 46, in order to compensate for the decrease in the number of turns of the first layer 1L, the number of turns after the second layer 2L is increased, and a decrease in the alignment of the winding 46 in the winding portion 45 can be suppressed.

[0074] Also, in the manufacturing method of the motor of the embodiment, the conducting wire is wound around at least one layer after the second layer 2L so as to satisfy 0.82B ≤ P ≤ B. The winding 46 wound after the second layer 2L is restricted in movement and is difficult to slip because it is wound on top of the winding 46 wound on the layer directly below it, so winding disorder is suppressed. For this reason, for example, by making it approximately the same size as the outer diameter of the conductor 46a in the conducting wire, the occupation ratio of the winding portion 45 can be increased.

[0075] Also, in the manufacturing method of the motor of the embodiment, the conducting wire is wound around all layers after the second layer 2L so as to satisfy P < B. Thereby, it is possible to achieve both preventing winding disorder in the first layer L1 and maximizing the occupation ratio of the winding portion 45.

[0076] Also, the outer diameter B of the conducting wire wound in the manufacturing method of the motor of the embodiment is the upper limit value of the dimensional tolerance of this outer diameter. Thereby, the action of preventing winding disorder of the winding 46 in the first layer 1L can be most appropriately obtained.

[0077] In addition, the manufacturing method of the electric motor of the embodiment winds a conducting wire using a winding machine having a nozzle N for supplying the conducting wire. Thereby, the control unit C of the winding machine controls the movement amount (winding pitch P) of the nozzle N, so that a winding portion 45 without winding disorder can be easily formed at a desired winding pitch P.

Explanation of Signs

[0078] 6 Electric motor 23 Stator core 25 (25A, 25B) Insulator 31 Yoke portion 32 (32-1 to 32-9) Stator core tooth portion (tooth portion) 41 Outer peripheral wall portion 42 (42-1 to 42-9) Insulator tooth portion (winding cylinder portion) 42a Flat surface 45, 55, 56 Winding portion 46 Winding 46a Conductor 46b Insulating film 49 Jumper wire A1 First cross-sectional area A2 Second cross-sectional area B Outer diameter of the conducting wire P Winding pitch 1L First layer 2L to 8L Second layer to eighth layer (at least one layer after the second layer) M Length N Nozzle 1T to 4T First turn to fourth turn Y Radial direction

Claims

1. a stator core having an annular yoke portion and teeth portions extending radially from the yoke portion; an insulator having a winding body attached to the teeth; a winding portion having a plurality of layers formed by a winding in which a conductor is wound around the teeth portion via the winding body portion, When the winding pitch of the conductor wire wound in the radial direction is P and the outer diameter of the conductor wire is B, a first layer of the winding portion having a conductor wire wound therein such that P>B is satisfied, and a second or subsequent layer of the winding portion has a conductor wire wound therein such that P≦B is satisfied in the radial direction.

2. The conductor is wound in the first layer so that P>1.02B is satisfied. A method for manufacturing the electric motor according to claim 1.

3. The conductor is wound in the first layer so that 2B>P is satisfied. A method for manufacturing the electric motor according to claim 1 or 2.

4. The conductor is wound in the at least one layer so that 0.82B≦P≦B is satisfied. A method for manufacturing the electric motor according to claim 1.

5. The conductor is wound so that P≦B is satisfied in the second and subsequent layers of the winding portion. A method for manufacturing the electric motor according to claim 1.

6. The outer diameter B of the conductor is the upper limit of the dimensional tolerance of the outer diameter, A method for manufacturing the electric motor according to claim 1.

7. winding the conductor wire using a winding machine having a nozzle for supplying the conductor wire; A method for manufacturing the electric motor according to claim 1.

8. a stator core having an annular yoke portion and teeth portions extending radially from the yoke portion; an insulator provided at an axial end of the stator core and having a winding body portion disposed on the teeth portion; a winding portion in which a plurality of layers are formed by a winding in which a conductor wire is wound around the teeth portion via the winding body portion, When a winding pitch of the conductor wire wound in the radial direction is P and an outer diameter of the conductor wire is B, In the radial direction, the winding pitch of the first layer of the winding portion satisfies P>B, an electric motor, wherein the winding pitch of at least one layer of the winding portion from the second layer onwards satisfies P≦B.

9. When viewed in a cross section of the winding drum along the radial direction, a surface of the winding drum around which the conductor wire is wound has a flat surface extending along the radial direction, where M is the length of the flat surface in the radial direction and T is the number of turns of the wire wound around the flat surface in the first layer, and (B×T)<M is satisfied.

9. The electric motor according to claim 8.

10. The winding wound in the first layer satisfies P>1.02B.

9. The electric motor according to claim 8.

11. The winding wound in the first layer satisfies 2B>P.

11. An electric motor according to any one of claims 8 to 10.

12. The winding wound in the at least one layer satisfies 0.82B≦P≦B.

9. The electric motor according to claim 8.

13. The winding wound in the second and subsequent layers of the winding portion satisfies P≦B.

9. The electric motor according to claim 8.

14. The outer diameter B of the conductor is the upper limit of the dimensional tolerance of the outer diameter, 9. The electric motor according to claim 8.

15. The conductor has a tensile strength of 460 [N / mm ２ ] is less than 9. The electric motor according to claim 8.

16. the insulator has an annular outer circumferential wall portion attached to the stator core, the conductor wire extends from the winding portion to the outer circumferential wall portion to form a crossover wire, When a first cross-sectional area perpendicular to the longitudinal direction of the winding wound in the first layer is A1 and a second cross-sectional area perpendicular to the longitudinal direction of the jumper wire is A2, (A1 / A2)>0.85 is satisfied.

9. The electric motor according to claim 8.

17. The conductive wire includes a conductor and an insulating film that covers the conductor, The static friction coefficient of the insulating film is 0.12 or less.

9. The electric motor according to claim 8.

18. The insulator contains glass fibers in an amount of 15% by weight or more and 45% by weight or less.

9. The electric motor according to claim 8.

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