阅读说明：本技术 定子的制造方法 (Method for manufacturing stator ) 是由 丹下宏司 于 2021-05-27 设计创作，主要内容包括：本发明的定子的制造方法降低向插槽插入线圈束时的阻力。定子的制造方法包括以下各工序：将线圈线卷绕成环状来形成线圈束(10),该线圈束具有收纳在插槽内的两个线圈边部(11)和连接两个线圈边部(11)且配置于定子铁芯的轴向两侧的线圈搭接部(12)；通过使线圈束(10)沿插槽的轴向相对移动来以线圈边部(11)收纳在插槽内且线圈搭接部(12)配置于定子铁芯的轴向两侧的方式,向插槽插入线圈束(10)；以及在向插槽插入的工序之前,通过相对于具有与插槽对应地沿轴向贯通的贯通孔(51)的铁芯夹具(50),使线圈束(10)沿贯通孔(51)的轴向相对移动,来向贯通孔(51)插入线圈边部(11)。(The invention provides a method for manufacturing a stator, which reduces resistance when inserting a coil bundle into a slot. The method for manufacturing the stator comprises the following steps: winding a coil wire in a ring shape to form a coil bundle (10) having two coil sides (11) housed in slots and coil lap parts (12) connecting the two coil sides (11) and disposed on both sides of a stator core in the axial direction; inserting the coil bundle (10) into the slot in such a manner that the coil side portion (11) is housed in the slot and the coil lap portions (12) are arranged on both sides of the stator core in the axial direction by relatively moving the coil bundle (10) in the axial direction of the slot; and inserting the coil side (11) into the through hole (51) by relatively moving the coil bundle (10) in the axial direction of the through hole (51) with respect to a core jig (50) having the through hole (51) that penetrates in the axial direction in correspondence with the slot, prior to the step of inserting into the slot.)

1. A method of manufacturing a stator including a stator core having a plurality of slots penetrating therethrough in an axial direction, the method comprising:

winding a coil wire in a ring shape to form a coil bundle having two coil side portions housed in the slot and coil lap portions connecting the two coil side portions and disposed on both sides of the stator core in an axial direction;

inserting the coil bundle into the slot so that the coil side portions are accommodated in the slot and the coil lap portions are arranged on both sides of the stator core in the axial direction by relatively moving the coil bundle in the axial direction of the slot; and

before the step of inserting the coil into the slot, the coil bundle is relatively moved in the axial direction of the through hole with respect to a core jig having a through hole penetrating in the axial direction in correspondence with the slot, and the coil side portion is inserted into the through hole.

2. The method of manufacturing a stator according to claim 1,

the socket has a socket opening as a radial opening,

the radial opening of the through hole has an opening width larger than that of the slot opening.

3. The method of manufacturing a stator according to claim 1 or 2,

the step of inserting the plug into the slot includes the following steps:

holding the coil bundle to a plurality of blades arranged radially inside the stator core in a circumferential direction of the stator core and extending in an axial direction; and

the coil bundle is moved by a coil moving mechanism which is disposed radially inside the blade and moves in an axial direction,

the step of inserting the through hole includes the steps of:

holding the coil bundle by a plurality of blade jigs arranged radially inside the core jig; and

the coil bundle is moved by a coil moving jig which is disposed radially inside the blade jig and moves in an axial direction.

4. A method of manufacturing a stator according to any one of claims 1 to 3,

the method further includes compressing at least a portion of the coil side portion between the step of inserting the coil into the through hole and the step of inserting the coil into the slot.

5. The method of manufacturing a stator according to claim 4,

in the compressing step, at least a part of the coil side portion is compressed in a state where the coil bundle is gripped by the gripping member with tension applied in the axial direction.

6. The method of manufacturing a stator according to claim 5,

the holding member is the core jig.

7. The method of manufacturing a stator according to any one of claims 4 to 6,

in the forming step, the coil wire is formed using a round wire,

in the compressing step, the cross-sectional shape of the coil wire is deformed into a square shape.

8. The method of manufacturing a stator according to any one of claims 4 to 7,

in the compressing step, the coil bundle is compressed so that an axial sectional shape of the coil bundle corresponds to an axial sectional shape of the slot.

9. The method of manufacturing a stator according to any one of claims 4 to 8,

in the compressing step, at least a part of the coil side is compressed by using a compression mold,

the compression mold includes a first mold and a second mold disposed outside the coil bundle, and a third mold disposed inside the coil bundle,

at least a part of the two coil side portions is compressed by the first mold and the third mold and the second mold and the third mold.

10. The method of manufacturing a stator according to claim 9,

in the compressing step, the first coil assembly and the second coil assembly disposed inside the first coil assembly are compressed,

the compression mold further includes a fourth mold disposed between the coil side portion of the first coil bundle and the coil side portion of the second coil bundle,

compressing at least a part of the two coil side portions of the first coil bundle with the first mold and the fourth mold and with the second mold and the fourth mold,

at least a part of the two coil side portions of the second coil bundle is compressed by the third mold and the fourth mold.

11. The method of manufacturing a stator according to claim 9 or 10,

in the compressing step, the plurality of coil bundles are compressed by using the plurality of compression molds,

each of the first molds is moved toward each of the second molds,

the first molds overlap each other in a plan view seen from a moving direction of the first molds.

12. The method of manufacturing a stator according to any one of claims 9 to 11,

the first mold is moved toward the second mold,

the compression mold further includes an opposing member that is disposed so as to extend in the moving direction of the first mold, is in contact with the first mold, and is disposed so as to face the first coil bundle and the second coil bundle with the coil bundle interposed therebetween in a direction perpendicular to the moving direction of the first mold and perpendicular to a direction in which the coil sides of the first coil bundle and the second coil bundle extend.

13. The method of manufacturing a stator according to any one of claims 1 to 12,

the stator core is an integrated stator core having an umbrella shape.

14. The method of manufacturing a stator according to any one of claims 1 to 13,

further comprising a step of bending one side of the coil bundle,

and inserting from the one side in the step of inserting into the slot.

Technical Field

The present invention relates to a method of manufacturing a stator.

Background

A method of manufacturing a stator by inserting a coil into a slot of a stator core is known. For example, japanese patent application laid-open No. 2000-125521 (patent document 1) discloses a coil insertion device for inserting a ring-shaped coil into a slot of a stator core.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. 2000-125521.

Disclosure of Invention

Problems to be solved by the invention

However, in the coil insertion device of patent document 1, when the annular coil is inserted into the slot, a large friction is generated between the coil and the inner surface of the slot.

The invention aims to provide a method for manufacturing a stator, which reduces resistance when inserting a coil bundle into a slot.

Means for solving the problems

A method of manufacturing a stator according to a first aspect of the present invention is a method of manufacturing a stator including a stator core having a plurality of slots penetrating in an axial direction, the method including the steps of: winding a coil wire in a ring shape to form a coil bundle having two coil side portions housed in the slot and coil lap portions connecting the two coil side portions and disposed on both sides of the stator core in an axial direction; inserting the coil bundle into the slot in such a manner that the coil side portions are accommodated in the slot and the coil lap portions are disposed on both sides of the stator core in the axial direction by relatively moving the coil bundle in the axial direction of the slot; and inserting the coil side portion into the through hole by relatively moving the coil bundle in the axial direction of the through hole with respect to an iron core jig having the through hole penetrating in the axial direction corresponding to the slot, prior to the step of inserting into the slot.

The effects of the invention are as follows.

The invention provides a method for manufacturing a stator, which can reduce resistance when inserting a coil bundle into a slot.

Drawings

Fig. 1 is a schematic view of a cross section of a stator perpendicular to an axial direction.

Fig. 2 is a schematic view showing one step of the stator manufacturing method.

Fig. 3 is a schematic view showing one step of the stator manufacturing method.

Fig. 4 is a schematic view showing one step of the stator manufacturing method.

Fig. 5 is a schematic view showing one step of the stator manufacturing method.

Fig. 6 is a schematic view showing one step of the stator manufacturing method.

Fig. 7 is a schematic view showing one step of the stator manufacturing method.

Fig. 8 is a side view of the core clamp.

Fig. 9 is a schematic view showing one step of the stator manufacturing method.

Fig. 10 is a schematic view showing one step of the stator manufacturing method.

Fig. 11 is a schematic view showing one step of the stator manufacturing method.

Fig. 12 is a schematic view showing one step of the stator manufacturing method.

Fig. 13 is a flowchart illustrating a method of manufacturing the stator.

In the figure:

1-stator, 10-coil bundle, 10 a-first coil bundle, 10 b-second coil bundle, 11a, 11 b-coil side, 12-coil lap, 20-stator core, 21-slot, 22-slot opening, 23-tooth, 40-wedge, 50-core clamp, 50 a-first core clamp, 50 b-second core clamp, 51-through hole, 60-blade clamp, 70-coil moving clamp, 80-compression mold, 81-first mold, 82-second mold, 83-third mold, 84-fourth mold, 85-opposed part, 110, 111, 112-blade, 120-film stripping machine.

Detailed Description

Hereinafter, embodiments of the present invention will be described based on the drawings. In the drawings, the same or corresponding portions are denoted by the same reference numerals, and description thereof will not be repeated.

In the following description, the direction in which the center axis of the stator 1 extends, that is, the penetrating direction of the slots, is referred to as the "axial direction". One side in the axial direction is referred to as an upper side, and the other side is referred to as a lower side. The vertical direction is used for determining the positional relationship, and is not limited to an actual direction. That is, the downward direction does not necessarily mean the gravity direction. The axial direction is not particularly limited, and includes a vertical direction, a horizontal direction, a direction intersecting the above-mentioned directions, and the like.

The direction perpendicular to the central axis of the stator 1 is referred to as the "radial direction". One side in the radial direction is an inner side, and the other side is an outer side. The direction along an arc centered on the central axis of the stator 1 is referred to as the "circumferential direction".

In the drawings used in the following description, a characteristic portion may be shown enlarged for convenience of description in order to emphasize the characteristic portion. Therefore, the size and the ratio of each component are not necessarily the same as the actual size and ratio. Note that, for the same purpose, portions that are not characteristic may be omitted from the drawings.

(stator)

As shown in fig. 1, the stator 1 is a component of a motor, and interacts with a rotor, not shown, to generate torque. The stator 1 of the present embodiment is wound in a distributed manner with the coil wound across several slots 21. The stator 1 includes a coil bundle 10 and a stator core 20.

< stator core >

The stator core 20 is formed in a hollow cylindrical shape. The stator core 20 is formed by overlapping thin silicon steel plates. A plurality of teeth 23 are radially formed on the stator core 20. Slots 21 are formed between the teeth 23. The teeth 23 extend radially through the slots 21. The slot 21 is formed with a slot opening 22 as a radial opening. The stator core 20 of the present embodiment is an integrated stator core.

< coil bundle >

As shown in fig. 2, the coil bundle 10 is formed by winding a coil wire in a ring shape. That is, the coil bundle 10 is a ring-shaped coil. The coil wire of the present embodiment is a round wire, but is not particularly limited thereto, and may be a flat wire or the like.

The coil bundle 10 has two coil side portions 11 and a coil lap portion 12. The two coil side portions 11 are housed in the slots 21. Specifically, the slot 21 that houses one coil side 11 is different from the slot 21 that houses the other coil side 11. The slot 21 for housing one coil side 11 and the slot 21 for housing the other coil side 11 may be adjacent to each other, or may be arranged in the circumferential direction with another slot 21 interposed therebetween.

The coil side 11 is wound in alignment. That is, in the aligned winding, the coil side portions 11 are regularly stacked in a predetermined direction. In the slot 21, the coil side portions 11 of the present embodiment are stacked in order in the circumferential direction, but the present invention is not limited to this.

The coil lap 12 connects the two coil side portions 11. The coil connecting portions 12 are disposed on both sides in the axial direction. Specifically, the coil lap 12 located on the upper side in the axial direction is an upper coil end portion connecting the upper end portions of the two coil side portions 11. The coil lap 12 located axially below is a lower coil end portion connecting the lower end portions of the coil side portions 11.

< wedge >

The wedge 40 shown in fig. 2 is disposed between the coil wire and the slot opening 22, wherein the coil wire is disposed in the slot 21. The wedge 40 blocks the socket opening 22.

(stator manufacturing apparatus)

A manufacturing apparatus of the stator 1 will be described with reference to fig. 1 to 12. Fig. 2 shows a state in which the coil bundle 10 held by the core holder 50 is arranged axially below the stator core 20. Fig. 3 is a schematic view of the wedge 40 and the core holder 50 in fig. 2 omitted and each member is simplified in shape. Fig. 4 and 5 are schematic views showing steps different from the manufacturing step of fig. 3.

The manufacturing apparatus of the stator 1 includes a plurality of blades 110 shown in fig. 2 to 5, a stripper 120 as a coil moving mechanism shown in fig. 3 to 5, a core jig 50 shown in fig. 2 and 6 to 8, a blade jig 60, a coil moving jig 70 shown in fig. 7, and a compression mold 80 shown in fig. 9 to 11.

< blade >

As shown in fig. 2 to 5, the plurality of blades 110 hold the coil bundle 10. The blades 110 are arranged radially inward of the stator core 20 in a circumferential direction of the stator core 20. The vanes 110 extend in the axial direction of the stator core 20. Specifically, the plurality of blades 110 are arranged on the same circumference corresponding to the teeth 23. With the blade 110, the coil bundle 10 can be easily inserted into the slot 21.

The blade 110 of the present embodiment includes two blades 111, 112. The blades 111, 112 are disposed with the plurality of teeth 23 therebetween. The blades 111, 112 guide one coil bundle 10 hooked to a later-described stripper 120 to the slot 21 in the axial direction and the radial direction. The blades 111, 112 are rod-like members extending in the axial direction. The blades 111, 112 are movable in the axial direction. In the present embodiment, the blades 111 and 112 are movable blades that move in the axial direction.

< stripper >

The stripper 120 as a coil moving mechanism is disposed radially inward of the stator core 20. The stripper 120 moves in the axial direction of the stator core 20. That is, the stripper 120 moves the coil bundle 10 in the axial direction. With the ejector 120, the coil bundle 10 is moved in the axial direction inside the stator core 20 in the radial direction, and a part of the coil bundle 10 is inserted from the slot opening 22 into the slot 21. Specifically, the stripper 120 hooks the inner side in the radial direction of the coil bundle 10 and lifts the coil bundle 10 along the blade 110.

The stripper 120 of fig. 3 to 5 includes a rotary shaft 121 and a large-diameter portion 122. The rotary shaft 121 extends in the axial direction. The large diameter portion 122 is provided at the other end portion in the axial direction of the rotary shaft 121. The radial inner side of the annular bundle 10 is hooked to the large diameter portion 122. The large diameter portion 122 has a diameter larger than that of the rotation shaft 121. The central axis of the rotation shaft 121 is the same as the central axis of the large diameter portion 122. The diameter of the large diameter portion 122 is the distance between the blades 111, 112.

< iron core Clamp >

As shown in fig. 2, 6, and 7, the core holder 50 includes a body portion 52 and a tooth portion 53.

The main body 52 has an opening portion including a plurality of through holes 51. The tooth portion 53 is disposed in the opening. Tooth 53 corresponds to tooth 23. When the tooth portion 53 is disposed in the opening of the body portion 52, a through hole 51 is formed, and the through hole 51 corresponds to the slot 21. The main body portion 52 and the tooth portion 53 are movable in the axial direction relative to each other.

The radial opening of the through hole 51 has an opening width wider than the slot opening 22. The opening width is the width in the circumferential direction.

In fig. 2, 6 and 7, the core holder 50 includes a first core holder 50a and a second core holder 50 b. Here, the core jig 50 has eight first core jigs 50a and eight second core jigs 50 b. The first core holder 50a is located at an axially upper side, and the second core holder 50b is located at an axially lower side. The first core holder 50a and the second core holder 50b hold the same coil side 11. Therefore, the number of the first core clamps 50a and the second core clamps 50b is the same.

The axial lengths of the first core holder 50a and the second core holder 50b are shorter than the axial length of the slot 21. Fig. 8 is a side view of the first core holder 50 a. As shown in fig. 8, the first core holder 50a includes a first surface 54 extending in the radial direction on the coil lap 12 side, and a second surface 55 on the opposite side of the coil lap 12. The second surface 55 is inclined so as to approach the coil bridge 12 side toward the radially outer side.

< holding part >

The gripping member is a member that applies tension in the axial direction to grip the coil bundle 10. Here, the holding member is a core jig 50. That is, the holding member is a member common to the core jig. The holding member may be a member different from the core holder 50.

< vane clamp >

The blade clamp 60 corresponds to the blade 110. The vane holder 60 is disposed radially inward of the core holder 50. The blade clamp 60 holds the coil bundle 10. The blade clamp 60 is provided in plurality. The blade holder 60 is a rod-shaped member extending in the axial direction. In fig. 6 and 7, a ring member 61 connected to the upper end portions of the plurality of blade clamps 60 is provided.

In the present embodiment, the blade holder 60 and the blade 110 are separate members, but may be a common member.

< coil moving jig >

The coil moving jig 70 shown in fig. 7 corresponds to a mold stripper 120 as a coil moving mechanism. The coil moving jig is disposed radially inward of the blade jig 60. The coil moving jig 70 moves the coil bundle 10 in the axial direction. The coil moving jig 70 is, for example, a hemispherical member.

In the present embodiment, the coil moving jig 70 and the coil moving mechanism (the stripper 120) are separate members, but may be a common member.

< compression mold >

As shown in fig. 9 and 10, the compression mold 80 compresses at least a part of the coil side 11. In the present embodiment, the compression mold 80 compresses the first coil bundle 10a and the second coil bundle 10b disposed inside the first coil bundle 10 a.

The first coil bundle 10a is larger than the second coil bundle 10 b. Specifically, the first coil bundle 10a is disposed so as to concentrically include the second coil bundle 10b inside. Therefore, the two insertion grooves 21 into which the second coil bundle 10b is inserted are located between the two insertion grooves 21 into which the first coil bundle 10a is inserted.

The compression mold 80 includes a first mold 81, a second mold 82, a third mold 83, a fourth mold 84, and an opposing member 85.

The first die 81 and the second die 82 are disposed outside the coil bundle 10. The outer side of the coil bundle 10 is opposite to the other coil side with one coil side therebetween. In fig. 9 and 10, the first die 81 and the second die 82 are disposed outside the first coil bundle 10a and the second coil bundle 10 b.

The first mold 81 is a movable mold. The second mold 82 is a stationary mold. The first die 81 is moved toward the second die 82.

The third mold 83 is disposed inside the coil bundle 10. The inner side of the coil bundle 10 is between the two coil sides 11. In fig. 9 and 10, the third mold is disposed inside the first coil bundle 10a and the second coil bundle 10 b. The third mold 83 is an intermediate mold.

The fourth mold 84 is disposed between the coil side 11 of the first coil bundle 10a and the coil side 11 of the second coil bundle 10 b. The fourth die 84 is a gap die.

The opposing member 85 extends in the moving direction of the first mold 81 (downward direction in fig. 10). The opposing member 85 is disposed in contact with the first mold 81. In fig. 10, the opposing member 85 is disposed in contact with the first mold 81 and the second mold 82. The opposing member 85 is disposed so as to face the first and second coil bundles 10a, 10b across from each other in a direction perpendicular to the moving direction of the first mold 81 and perpendicular to the direction in which the coil sides 11a, 11b of the first and second coil bundles 10a, 10b extend. The opposing member 85 is a guide.

At least a part of the two coil sides 11a of the first coil bundle 10a is compressed by the first and fourth molds 81 and 84 and the second and fourth molds 82 and 84 in a state where the coil sides 11a are sandwiched by the facing members 85. At least a part of the two coil sides 11b of the second coil bundle 10b is compressed by the third mold 83 and the fourth mold 84 in a state where the coil sides 11b are sandwiched by the facing members 85.

Fig. 12 is a schematic view of a state in which a plurality of coil bundles 10 are inserted into through-holes 51 of core jig 50 shown in fig. 6, and is converted into a straight line. Fig. 11 is a schematic diagram showing a state in which the coil side 11 of the coil bundle 10 in fig. 12 is compressed by the compression mold 80. In the present embodiment, a plurality of compression molds 80 are used as shown in fig. 11. When the plurality of compression molds 80 are viewed in a plan view from the moving direction of the first mold 81 (downward direction in fig. 11), the first molds 81 overlap each other.

(method of manufacturing stator)

Next, a method of manufacturing a stator according to the present embodiment will be described with reference to fig. 1 to 13. The manufacturing method of the present embodiment is a manufacturing method of a stator 1 including a stator core 20, and the stator core 20 has a plurality of slots 21 penetrating in an axial direction.

First, as shown in fig. 13, the coil wire is wound in a ring shape to form a coil bundle 10 having two coil sides 11 and a coil lap 12, the two coil sides 11 being housed in the slot 21, and the coil lap 12 being disposed on both sides of the stator core 20 in the axial direction so as to connect the two coil sides 11 (step S10). In this step (step S10), a coil wire of a round wire is used. Specifically, for example, the coil wire is wound in a loop shape using a winding die, thereby forming the coil bundle 10.

Next, the coil bundle 10 is relatively moved in the axial direction of the through hole 51 with respect to the core jig 50, and the coil side 11 is inserted into the through hole 51, wherein the core jig 50 has the through hole 51 penetrating in the axial direction corresponding to the slot 21 (step S20). This step (step S20) is performed before the step (step S40) of inserting the substrate into the slot 21 described below.

Specifically, as shown in fig. 6 and 7, the coil bundle 10 is held by the plurality of blade jigs 60, and the plurality of blade jigs 60 are arranged radially inward of the core jig 50 (step S21). Then, the coil bundle 10 is moved by the coil moving jig 70 which is disposed radially inward of the blade jig 60 and moves in the axial direction (step S22). Specifically, the inner side of the coil bundle 10 is lifted upward in a state of being hooked on the coil moving jig 70 by moving the coil moving jig 70 upward in the axial direction. This allows the coil bundle 10 to be inserted into the through hole 51 of the core holder 50. In this way, the coil bundle 10 can be easily inserted into the through hole 51 by using the blade jig 60 and the coil moving jig 70.

In this step (step S20), the coil side portion 11 may be inserted into the through hole 51 as described below. One end of the coil side 11 is inserted into the through hole 51 of the first core holder 50a and the through hole 51 of the second core holder 50 b. Then, the second core jig 50b is relatively moved to the other end portion of the coil side 11 while the coil side 11 is held by the first core jig 50 a. Alternatively, the first core jig 50a is relatively moved to the other end portion of the coil side 11 in a state where the coil side 11 is held by the second core jig 50 b.

By performing this step (step S20), the coil side 11 can be formed into a shape corresponding to the slot 21.

The radial opening of the through hole 51 has a wider opening width than the slot opening 22. Therefore, in the step of inserting the coil assembly 10 into the through-hole 51 (step S20), the resistance when inserting the coil assembly 10 into the through-hole 51 can be reduced.

Next, at least a part of the coil side 11 is compressed (step S30). In the present embodiment, the compression step (step S30) is performed between the step of inserting the through-hole 51 (step S20) and the step of inserting the socket 21 (step S40) described below. The compressing step (step S20) may be performed simultaneously with the inserting step (step S40).

In this step (step S30), at least a part of the coil side 11 is compressed while the coil bundle 10 is gripped by applying tension in the axial direction by the core jig 50 as a gripping member. That is, at least a part of the coil side portion 11 extending in the axial direction of the coil bundle 10 is compressed in a state where the coil bundle 10 is gripped by applying tension in the axial direction by the core jig 50 as a gripping member. Thus, the compressed coil side 11 can be inserted into the slot 21 when the insertion step (step S40) described below is performed. Therefore, the coil wire can be suppressed from being scattered. Therefore, the stator 1 in which the space factor of the coil wire is increased can be manufactured. The tension applied to the coil bundle 10 may include an axial component. Therefore, the tension applied to the coil bundle 10 can also be inclined with respect to the axial direction.

In the present embodiment, the core jig 50 is used as the holding member. Since the holding member and the core jig 50 are common members, the number of members required for manufacturing the stator 1 can be reduced.

In the compressing step (step S30), at least a part of the coil side portion 11 is compressed in at least one of the circumferential direction and the radial direction of the stator core 20. That is, in this step (step S30), at least a part of the coil side 11 is compressed in a direction perpendicular to the direction in which the coil side 11 extends. In the present embodiment, as shown in fig. 11, at least a part of the coil side portion 11 is compressed in the circumferential direction of the stator core 20.

In the compressing step (step S30), the coil bundle 10 is compressed so that the axial sectional shape of the coil bundle 10 corresponds to the axial sectional shape of the slot 21. Since the coil bundle 10 can be compressed so as to correspond to the slot 21, the space factor can be further improved. In the compressing step (step S30), the cross-sectional shape of the coil wire is deformed into a square shape. The cross-sectional shape of the round wire is deformed into a square shape by compression, thereby increasing the space factor.

In the compression step (step S30) of the present embodiment, at least a part of the coil side portion 11 is compressed using the compression mold 80 shown in fig. 9 and 10. By using the compression mold 80, at least a part of the two coil side portions 11 can be easily compressed.

Specifically, at least a part of the two coil side portions 11 is compressed by the first and third molds 81 and 83 and the second and third molds 82 and 83. In the present embodiment, the entire two coil side portions 11 are compressed by the first and third molds 81 and 83 and the second and third molds 82 and 83.

Then, in this step (step S30), the first coil bundle 10a and the second coil bundle 10b disposed inside the first coil bundle 10a are compressed. Specifically, at least a part of the two coil sides 11a of the first coil bundle 10a is compressed by the first and fourth molds 81 and 84 and the second and fourth molds 82 and 84, and at least a part of the two coil sides 11b of the second coil bundle 10b is compressed by the third and fourth molds 83 and 84. In the present embodiment, the entire two coil sides 11a of the first coil bundle 10a are compressed by the first and fourth molds 81 and 84 and the second and fourth molds 82 and 84, and the entire two coil sides 11b of the second coil bundle 10b are compressed by the third and fourth molds 83 and 84.

In this step (step S30), the first die 81 is moved toward the second die 82 while the coil bundle 10 (here, the first coil bundle 10a and the second coil bundle 10b) is held between the facing members 85. The opposing member 85 can restrict the moving direction of the first mold 81 to one direction.

In this step (step S30), as shown in fig. 11, the plurality of coil bundles 10 are compressed by using the plurality of compression dies 80. The first molds 81 are moved toward the second molds 82, and the first molds 81 are overlapped with each other in a plan view seen from the moving direction of the first molds 81. This allows at least a part of the coil side portions 11 of the plurality of coil bundles 10 to be compressed at the same time. Therefore, the efficiency of inserting the coil bundle 10 into the slot 21 can be further improved.

By performing the compressing step (step S30), at least a part of the coil side 11 inserted into the through hole 51 can be compressed. Therefore, in the step of inserting into the slot (step S40) described below, the compressed coil side portion 11 can be inserted into the slot 21. Therefore, the space factor of the coil wire can be increased. In the step of inserting the coil wire into the slot (step S40), damage to the coating film by the coil wire can be suppressed.

Next, the coil bundle 10 is inserted into the slot 21 so that the coil side portions 11 are accommodated in the slot 21 and the coil lap portions 12 are arranged on both sides in the axial direction of the stator core 20 by relatively moving the coil bundle 10 in the axial direction of the slot 21 (step S40). This step (step S40) includes a step of inserting the coil lap 12 on the upper side of the stator core 20 into the slot 21.

In this step (step S40), as shown in fig. 2 and 3, the coil bundle 10 is held by the plurality of blades 110, and the plurality of blades 110 are arranged inside the stator core 20 in the radial direction and extend in the axial direction so as to be aligned in the circumferential direction of the stator core 20 (step S41). Specifically, after the compression step (step S30), as shown in fig. 2, the blade jig 60 is removed, and the core jig 50 holds the upper end and the lower end of the coil side 11 of the coil bundle 10. In this way, the coil bundle 10 can be conveyed while being held by the core jig 50. Then, the coil bundle 10 is held by the blade 110 in a state where the coil bundle 10 is held by the core jig 50. In fig. 2, the wedge 40 is held by the blade 110 together with the coil bundle 10.

As shown in fig. 2 and 3, the coil bundle 10 is disposed axially below the stator core 20. Specifically, the coil bundle 10 is disposed so as to be held between the blades 111 and 112. As shown in fig. 3, the stripper 120 is disposed at the center in the radial direction and axially below the plurality of blades 111 and 112.

Thereafter, as shown in fig. 4, the coil bundle 10 is moved by the stripper 120 as a coil moving mechanism disposed radially inside the blade 110 and moving in the axial direction (step S42). In step S42, the core holder 50 is removed.

Specifically, the stripper 120 moves upward in the axial direction together with the blade 110. In this movement, the vanes 111, 112 are located radially inward of the stator core 20. In the present embodiment, the blade 110 is raised and the stripper 120 is raised. Since the inner side of the coil bundle 10 moves in a state of being hooked on the stripper 120, the coil bundle 10 moves upward in the axial direction.

When the coil bundle 10 is moved upward in the axial direction, the tooth portion 53 of the core jig 50 is moved downward, and the gap between the coil bundle 10 and the body portion 52 of the core jig 50 is increased. In this state, when the coil bundle 10 is moved upward in the axial direction, the body portion 52 of the core jig 50 stays at the lower end surface of the stator core 20. Therefore, the core jig 50 is removed in the process of inserting the coil bundle 10 (step S40), and the core jig 50 is not inserted into the slot 21.

As the blade 110 and the ejector 120 are moved in this way, the coil bundle 10 is moved in the axial direction on the radially inner side of the stator core 20, and a part of the coil bundle 10 is inserted into the slot 21 from the slot opening 22. As a result, as shown in fig. 5, the coil bundle 10 can be inserted into the slot 21 of the stator core 20.

Next, the blades 110 are detached from the stator core 20. Then, the stripper 120 is moved downward.

By performing the above steps (steps S10 to S40), the coil bundle 10 in which the coil wire is annularly wound can be inserted into the plurality of slots 21 penetrating in the axial direction of the stator core 20. Thus, the stator 1 shown in fig. 1 can be manufactured.

According to the method of manufacturing a stator of the present embodiment, since the coil side portion 11 of the coil bundle 10 is inserted into the through hole 51 of the core jig 50 corresponding to the slot 21 (step S20), the coil side portion 11 can be formed into a shape corresponding to the slot 21. Since the coil bundle 10 having the coil side 11 shaped to correspond to the slot 21 is inserted into the slot 21, friction between the inner surface of the slot 21 and the coil bundle 10 can be reduced. Therefore, resistance when inserting the coil bundle 10 into the insertion slot 21 can be reduced.

In the coil insertion device of patent document 1, when the annular coil is inserted into the slot, the sectional shape of the coil bundle is greatly different from the slot shape, and large friction is generated between the edge of the slot end face and the inner surface of the slot and the coil, and as a result, the space factor of the coil wire is lowered to a level of 50% or less. The space factor here is a value obtained by dividing the cross-sectional area of the copper wire portion of the coil wire by the area of the slot other than the insulating paper.

In the present embodiment, after the coil bundle 10 is formed (step S10), the coil side 11 of the coil bundle 10 is inserted into the through hole 51 (step S20), so that the cross-sectional shape of the coil bundle 10 can be adjusted to the shape of the slot 21. As a result, the space factor of the coil wire becomes high.

In the present embodiment, it is preferable that the step of bending one side of the coil bundle 10 is further provided, and the insertion is performed from one side in the step of inserting the coil bundle into the slot 21 (step S40). By bending one side of the coil bundle 10 to form the slot passage portion by making the shape of the coil end portion into a bent posture, the resistance when inserting the coil bundle 10 into the slot 21 can be reduced. The space factor of the coil wire can be increased to 54% or more by aligning the sectional shape of the coil bundle 10 with the slot shape, forming the slot passing portion by forming the coil end in a bent posture, and inserting the coil bundle 10 into the slot from the other side toward the one side in the axial direction.

In the step of compressing the coil side portion (S30), the cross-sectional shape of the coil bundle 10 is compressed into a slot shape, the shape of the coil end portion is brought into a bent posture to form a slot passing portion, and the coil bundle 10 is inserted into the slot from the other side toward the one side in the axial direction, whereby the space factor of the coil wire can be increased to 55% or more and the upper limit of the level of the space factor of the electric conductor (55% to 62%) in the construction method of inserting the electric conductor in the form of a substantially U-shape, which is segmented by cutting a copper wire having a flat cross-section into a predetermined length and substantially bending it into a U-shape, can be exceeded. The resistance when inserting the coil bundle 10 into the insertion slot 21 when the step of bending one side of the coil bundle 10 is performed is smaller than the resistance when inserting the substantially U-shaped electric conductor into the insertion slot.

The stator 1 manufactured by the manufacturing method of the present embodiment can be implemented on the integrated stator core 20 having an umbrella shape, which is used for a traction motor or the like that is strictly required to have low vibration and low noise, and can increase the space factor of the coil wire. Here, the integrated stator core 20 is a stator core 20 including an annular core back, a plurality of teeth 23 extending in the radial direction from the core back and arranged in the circumferential direction, and a plurality of slots 21 provided between the teeth 23 adjacent in the circumferential direction and penetrating in the axial direction. The umbrella shape refers to a shape extending in the circumferential direction at the radial end of the tooth 23.

(modification example)

In the above-described embodiment, the method of manufacturing the stator 1 using the core jig 50 having a length shorter than the axial length of the slot 21 has been described, but the axial length of the core jig 50 is not limited. The axial length of the core holder 50 may be the same as the axial length of the slot 21 or may be longer than the axial length of the slot 21.

The embodiments disclosed herein are to be considered in all respects as illustrative and not restrictive. The scope of the present invention is defined by the claims, rather than the embodiments described above, and all modifications equivalent in meaning and scope to the claims are intended to be included therein.