JP7392414B2 - rotating electric machine - Google Patents

Description

The present invention relates to a rotating electric machine.

Conventionally, a stator of a rotating electric machine has, for example, a plurality of coils each having an axial coil section extending in the axial direction and a coil end section connecting a pair of axial coil sections in the circumferential direction, and coil ends of different phases. There is one in which the sections are arranged in parallel inside and outside in the radial direction (see, for example, Patent Document 1).

Japanese Patent Application Publication No. 2014-121102

However, in the above-mentioned rotating electric machine, there is a problem in that heat dissipation from the coil end is poor due to the configuration in which the coil end is molded in a resin material, and the coil and, by extension, the rotating electric machine tend to become hot. In particular, the above-mentioned rotating electric machine is a slotless type in which the teeth are not arranged in the circumferential direction between the axial coil parts connected at the coil end part, and the axial coil parts of the coils of other phases are arranged. Since this is a rotating electrical machine and there is no heat dissipation from the teeth, the above problem becomes noticeable.

The present invention has been made to solve the above problems, and its purpose is to provide a rotating electrical machine with good heat dissipation.

A rotating electric machine (11) that solves the above problem includes an axial coil part (21a, 22a) extending in the axial direction and a coil end part (21b, 21c, 22b, 22c), and the coil end portion includes an inner coil end portion (22b) disposed on the radially inner side and an outer coil end portion (22b) disposed on the radially outer side of the inner coil end portion. A rotating electrical machine having a coil end portion (21b), which is provided with a heat dissipation portion (31 to 34, 37) in radial contact between the inner coil end portion and the outer coil end portion in the radial direction. ) is provided.

According to this configuration, the heat dissipation portion that contacts the inner coil end portion and the outer coil end portion in the radial direction is provided between the inner coil end portion and the outer coil end portion in the radial direction, so that heat dissipation from the coil end portion is improved.

FIG. 1 is a cross-sectional view of a rotating electrical machine in one embodiment. FIG. 2 is a partial perspective view of a stator in one embodiment. FIG. 1 is a partially enlarged sectional view of a rotating electric machine in one embodiment. FIG. 7 is a partially enlarged sectional view of a rotating electrical machine in another example. FIG. 7 is a partially enlarged sectional view of a rotating electrical machine in another example. FIG. 7 is a partially enlarged sectional view of a rotating electrical machine in another example. FIG. 7 is a partially enlarged sectional view of a rotating electrical machine in another example.

Hereinafter, one embodiment of a slotless type rotating electrical machine will be described according to FIGS. 1 to 3.
As shown in FIG. 1, the rotating electric machine 11 includes a cylindrical motor housing 12, a first end housing 13 that closes one opening of the motor housing 12, and a second end housing 13 that closes the other opening of the motor housing 12. and an end housing 14. The motor housing 12, the first end housing 13, and the second end housing 14 constitute a housing H of the rotating electrical machine 11, and are each made of aluminum or stainless steel metal materials. The rotating electric machine 11 also includes a substantially cylindrical stator 15 arranged along the inner peripheral surface of the motor housing 12 .

The rotating electric machine 11 also includes a rotor 17 rotatably supported by a first end housing 13 and a second end housing 14 via a bearing 16 inside the stator 15 .
The rotor 17 includes a rotating shaft 17a supported by a bearing 16, a rotor core 17b fitted and fixed to the rotating shaft 17a, and a permanent magnet 17c fixed to the outer peripheral surface of the rotor core 17b.

As shown in FIGS. 1 and 2, the stator 15 includes a cylindrical stator core 18 that functions as part of a magnetic circuit, and a plurality of coils 20 arranged along the inner peripheral surface of the stator core 18. The coil 20 is made by winding a rectangular wire made of an enamel-coated conductor many times in a ring shape, and the cross sections of the rectangular wire are arranged side by side with almost no gaps in the cross section of the ring shape. It is something. Note that in FIGS. 1 to 3, illustrations of boundaries between flat wires are omitted. Further, both ends of the rectangular wire in the coil 20 are connected to a drive circuit, but illustrations of both ends of the rectangular wire and the drive circuit are omitted in FIGS. 1 to 3.

As shown in FIG. 2, the coil 20 of this embodiment includes a first coil 21 and a second coil 22 that are bent into two different shapes. The first coil 21 and the second coil 22 each include a pair of axial coil parts 21a and 22a that extend in the axial direction, and coil end parts 21b and 21c that connect the pair of axial coil parts 21a and 22a in the circumferential direction. 22b and 22c.

The coil end portion 21b on one axial side of the first coil 21 constitutes an outer coil end portion, and includes an outer extension portion 21d that is bent and extends radially outward from the axial coil portion 21a, and the outer extension portion 21d. It has an axially extending portion 21e that extends from the distal end thereof in a bent manner to one side in the axial direction, and a first one-way connecting portion 21f that extends in the circumferential direction and connects the axially extending portions 21e. Further, the coil end portion 21c on the other side in the axial direction of the first coil 21 has an inner extension portion 21g that is bent and extends radially inward from the axial coil portion 21a, and an inner extension portion 21g that extends in the circumferential direction and connects the inner extension portions 21g. It has a first other connecting portion 21h.

Further, the coil end portion 22b on one side in the axial direction of the second coil 22 constitutes an inner coil end portion, and extends in the circumferential direction without being bent from the axial coil portion 22a. It has a second one-way connecting portion 22d that connects the two. The coil end portion 22c on the other side in the axial direction of the second coil 22 has an inner extension portion 22e that is bent and extends radially inward from the axial coil portion 21a, and an inner extension portion 22e that extends in the circumferential direction and connects the inner extension portions 22e. It has a second other connecting portion 22f.

In the stator 15, the axial coil portions 21a and 22a of the coil 20 of the other phase are connected in the circumferential direction between the axial coil portions 21a and 22a connected at the coil end portions 21b, 21c, 22b, and 22c. It is located. Specifically, first, the first coil 21 and the second coil 22 are arranged alternately, half overlapping each other in the circumferential direction. Further, the first coil 21 and the second coil 22 arranged in the circumferential direction are allocated so as to repeat U-phase, V-phase, and W-phase. That is, for example, the first coil 21 serving as the reference is set to be the U-phase, the second coil 22 arranged half-overlapping on one side in the circumferential direction is set as the V-phase, and the second coil 22 arranged half-overlapping on one side in the circumferential direction is set as the V-phase. The first coil 21 is the W phase, the second coil 22 disposed half overlapping on one side in the circumferential direction is the U phase, and the first coil 21 half overlapping on the other side in the circumferential direction is the V phase. , the second coil 22 disposed so as to overlap half on one side in the circumferential direction is the W phase, and the U phase, V phase, and W phase are assigned so as to repeat this process. For example, between the pair of axial coil parts 21a of the first coil 21 of the U phase in the circumferential direction, one axial coil part 22a of the second coil 22 of the V phase and the second coil part 22a of the W phase One axial coil portion 22a in the coil 22 is arranged. For example, between the pair of axial coil parts 22a in the V-phase second coil 22 in the circumferential direction, one axial coil part 21a in the U-phase first coil 21 and the W-phase first One axial coil portion 21a in the coil 21 is arranged. Further, for example, between the pair of axial coil portions 21a of the first coil 21 of the W phase in the circumferential direction, one axial coil portion 22a of the second coil 22 of the V phase and the second coil portion 22a of the U phase One axial coil portion 22a in the coil 22 is arranged.

As shown in FIGS. 1 to 3, the coil end portion 21b on one side in the axial direction of the first coil 21 is an outer coil end portion disposed on the outside in the radial direction, and the coil end portion 21b on one side in the axial direction in the second coil 22 The side coil end portion 22b is an inner coil end portion disposed radially inward. That is, the coil end portion 21b on one axial side of the first coil 21 has an outer extension portion 21d that is bent and extends radially outward, so that the first one connecting portion 21f has a diameter larger than that of the second other connecting portion 22f. placed on the outside.

Further, as shown in FIGS. 1 and 2, the coil end portion 21c on the other axial side of the first coil 21 and the coil end portion 22c on the other axial side of the second coil 22 are arranged side by side in the axial direction. ing.

Here, as shown in FIG. 3, between the coil end part 22b, which is the inner coil end part, and the coil end part 21b, which is the outer coil end part, there is a heat dissipation part that contacts them in the radial direction. A heat transfer member 31 is provided.

Specifically, first, the motor housing 12 has a large inner diameter portion 12a with an increased inner diameter at one end in the axial direction, and by forming the large inner diameter portion 12a, it forms a surface that is continuous with the one end surface in the axial direction of the stator core 18. It has a stepped surface 12b. The heat transfer member 31 has an annular fixing portion 31a that is press-fitted into the large inner diameter portion 12a while axially abutting the stepped surface 12b and one axial end surface of the stator core 18. Further, the heat transfer member 31 extends axially from the radially inner side of the fixing portion 31a and passes through the first coil 21, and includes the coil end portion 22b, which is an inner coil end portion, and the coil end portion, which is an outer coil end portion. It has an intervening part 31b interposed between the end parts 21b in the radial direction. In addition, in this embodiment, the tip of the intervening portion 31b is set to abut on the first end housing 13 in the axial direction. Further, in this embodiment, the radially outer end surface of the coil end portion 21b, which is the outer coil end portion, is set to abut in the radial direction on the inner circumferential surface of the large inner diameter portion 12a of the motor housing 12. Further, in this embodiment, the radially inner end surface of the coil end portion 22b, which is the inner coil end portion, is set to abut on the step surface 13a of the first end housing 13 in the radial direction. Further, the heat transfer member 31 of this embodiment includes a high heat transfer material such as an aluminum-based metal material, for example, the inside is made of an aluminum-based metal material and the surface is made of an insulating material such as a thin resin material. .

Next, the operation of the rotating electric machine 11 configured as described above will be explained.
When a three-phase drive current is supplied from the drive circuit to the coil 20 of the stator 15, a rotating magnetic field is generated in the stator 15, and the rotor 17 is rotationally driven. At this time, the coil 20 generates heat, which is radiated from the coil end portions 21b and 22b via the heat transfer member 31.

Next, the effects of the above embodiment will be described below.
(1) A heat transfer member 31 as a heat dissipation portion is provided between the coil end portion 22b, which is the inner coil end portion, and the coil end portion 21b, which is the outer coil end portion, in the radial direction. Because of this, heat dissipation from the coil end portions 21b and 22b is improved.

(2) Since the heat radiation part is the heat transfer member 31 fixed in contact with the motor housing 12 in the housing H, the heat of the coil end parts 21b and 22b is transferred to the housing H via the heat transfer member 31. This improves heat dissipation.

(3) In the rotating electric machine 11 of this embodiment, teeth are not disposed between the axial coil parts 21a and 22a connected to each other at the coil end parts 21b, 21c, 22b, and 22c in the circumferential direction. This is a slotless type rotating electric machine 11 in which axial coil portions 21a and 22a of a coil 20 are arranged. That is, the rotating electrical machine 11 of this embodiment is a type of rotating electrical machine 11 in which heat is not radiated from the teeth and the heat dissipation of the coil 20 is poor. Therefore, the effect of improving the heat dissipation from the coil end portions 21b and 22b becomes greater.

(4) Since the distal end of the intervening portion 31b of the heat transfer member 31 is set to contact the first end housing 13 in the axial direction, the heat transfer member 31 is in contact with the housing H at two locations. Therefore, the heat of the coil end portions 21b and 22b is easily transferred to the housing H via the heat transfer member 31, and heat dissipation becomes better.

(5) Since the radially outer end surface of the coil end portion 21b, which is the outer coil end portion, is set to radially abut on the inner circumferential surface of the large inner diameter portion 12a of the motor housing 12, the coil end portion Heat dissipation from 21b becomes better.

(6) Since the radially inner end surface of the coil end portion 22b, which is the inner coil end portion, is set to radially abut against the stepped surface 13a of the first end housing 13, Heat dissipation becomes better.

The above embodiment can be modified and implemented as follows. Further, this embodiment and the following modified examples can be implemented in combination with each other within a technically consistent range.
- In the above embodiment, the heat dissipation part provided between the coil end part 22b, which is the inner coil end part, and the coil end part 21b, which is the outer coil end part, is fixed so as to be in contact with the motor housing 12. However, other configurations may be used as long as the heat dissipation from the coil end portions 21b and 22b can be improved.

For example, as shown in FIG. 4, the heat radiation part may be a heat transfer part 32 integrally molded with the motor housing 12 in the housing H. The heat transfer portion 32 of this example is formed in the same shape as the heat transfer member 31 of the above embodiment and is integrally molded with the motor housing 12. In this way, the heat of the coil end portions 21b, 22b is transmitted to the housing H, and heat dissipation is improved without requiring any separate members. Further, in this example (see FIG. 4), a coolant passage 12c is formed inside the motor housing 12, and a coolant R such as water is filled in the passage 12c. In this way, heat dissipation becomes better.

Further, for example, as shown in FIG. 5, the heat dissipation section may have a structure in which a liquid passage member 33 having a cooling liquid passage 33a therein is filled with a cooling liquid R such as water. Note that, of course, the coolant R may be circulated by some kind of force such as a pump. In this way, the heat of the coil end portions 21b and 22b can be efficiently transferred to the cooling liquid R in the passage 33a of the liquid path member 33, and the heat dissipation performance becomes better.

Further, for example, as shown in FIG. 6, the heat radiation part may be a heat transfer part 34 integrally molded with the first end housing 13 of the housing H. The heat transfer part 34 in this example projects axially from the first end housing 13 and is arranged between the coil end part 22b, which is an inner coil end part, and the coil end part 21b, which is an outer coil end part, in the radial direction. has been done. Even in this case, the heat of the coil end portions 21b and 22b is transmitted to the housing H, and the heat dissipation is improved without requiring any special separate members.

- In the above embodiment, the inner rotor type rotating electrical machine 11 is used, but the present invention is not limited to this, and the rotating electrical machine 11 may be an outer rotor type rotating electrical machine.
For example, as shown in FIG. 7, a heat dissipation part 37 is provided between a coil end part 35, which is an inner coil end part, and a coil end part 36, which is an outer coil end part. The rotary electric machine may include a stator 38 and a rotor 39 provided on the outside of the stator 38 in the radial direction.

- In the above embodiment, the rotating electric machine 11 is a slotless type rotating electric machine in which teeth are not arranged between the axial coil parts 21a and 22a connected at the coil end parts 21b, 21c, 22b, and 22c in the circumferential direction. 11, but the present invention is not limited thereto, and a rotating electric machine may be used in which teeth are arranged between the axial coil portions 21a and 22a in the circumferential direction.

- In the above embodiment, the tip of the intervening part 31b in the heat transfer member 31 is set to abut on the first end housing 13 in the axial direction, but the present invention is not limited to this, and the intervening part in the heat transfer member 31 A configuration may be adopted in which the tip of the tip 31b does not come into contact with the first end housing 13 in the axial direction.

- In the above embodiment, the radially outer end surface of the coil end portion 21b, which is the outer coil end portion, is set to radially abut against the inner circumferential surface of the large inner diameter portion 12a of the motor housing 12. However, the present invention is not limited to this, and a configuration may be adopted in which the radially outer end surface of the coil end portion 21b does not contact the motor housing 12 in the radial direction.

- In the above embodiment, the radially inner end surface of the coil end portion 22b, which is the inner coil end portion, is set to contact the stepped surface 13a of the first end housing 13 in the radial direction. The present invention is not limited to this, and a configuration may be adopted in which the radially inner end surface of the coil end portion 22b does not contact the first end housing 13 in the radial direction.

- In the above embodiment, the first end housing 13 and the second end housing 14 are separate from the motor housing 12, but the present invention is not limited to this, and either the first end housing 13 or the second end housing 14 One side may be integrated with the motor housing 12.

- Although not specifically mentioned in the above embodiment, an insulating paper, an insulating cover, or the like may be interposed between the coil end portions 21b, 22b and the housing H. Further, the heat transfer member 31 is made of only a high heat transfer material such as an aluminum-based metal material, and insulating paper, an insulating cover, etc. are interposed between the heat transfer member 31 and the coil end portions 21b and 22b. It's okay.

DESCRIPTION OF SYMBOLS 11... Rotating electric machine, 20... Coil, 21... First coil (coil), 22... Second coil (coil), 21a, 22a... Axial direction coil part, 21b, 21c, 22b, 22c, 35, 36... Coil end Part, 31... Heat transfer member (heat radiation part), 32, 34... Heat transfer part (heat radiation part), 33... Liquid path member (heat radiation part), 33a... Passage, 37... Heat radiation part, H... Housing.

Claims (5)

A coil (20) having an axial coil portion (21a, 22a) extending in the axial direction and a coil end portion (21b, 21c, 22b, 22c, 35, 36) that connects the pair of axial coil portions in the circumferential direction. ~22),
The coil end part is a rotating coil having an inner coil end part (22b, 35) arranged radially inwardly, and an outer coil end part (21b, 36) arranged radially outwardly of the inner coil end part. It is an electric machine,
A heat dissipation portion (31 to 34, 37) is provided between the inner coil end portion and the outer coil end portion in the radial direction, and is in contact with the inner coil end portion and the outer coil end portion in the radial direction.
The outer coil end portion includes an outer extension portion (21d) that is bent and extends radially outward from the axial coil portion, and an axial extension portion (21e) that is bent and extended in the axial direction from the tip of the outer extension portion. It has a connecting part (21f) extending in the circumferential direction and connecting the pair of axially extending parts,
The heat dissipation section is a rotating electric machine having an intervening section (31b) interposed between the inner coil end section and the connecting section of the outer coil end section in the radial direction . The rotating electric machine according to claim 1, wherein the heat radiation section includes a heat transfer member (31) fixed so as to be in contact with the housing (H). The rotating electrical machine according to claim 1 or 2, wherein the heat radiation section includes a heat transfer section (32, 34) integrally molded with the housing. The rotating electric machine according to any one of claims 1 to 3, wherein the heat radiation section includes a liquid path member (33) having a passage (33a) for cooling liquid therein. According to any one of claims 1 to 4, the axial coil part of the coil of another phase is arranged between the axial coil parts connected at the coil end part in the circumferential direction. The rotating electric machine described.