JP2023174314A - stator - Google Patents

Abstract

To provide a stator in which a coil winding unit in a preliminarily shaped state can be assembled to teeth from outside in a radial direction of a stator core, and the roundness of an inner peripheral portion of the stator core can be improved.SOLUTION: A stator 10 includes a stator core 14. The stator core 14 includes a plurality of teeth 20 arranged in an annular shape, and a plurality of back yokes 22 that are separate from the plurality of teeth 20 and are respectively disposed between the plurality of teeth 20. Each of the teeth 20 includes a body portion 24 extending toward an inside in a radial direction of the stator core 14 with respect to the plurality of back yokes 22, and connection units 26 interposed between adjacent back yokes 22 among the plurality of back yokes 22 and connected to the adjacent back yokes 22, respectively. A breadth W2 of the connection unit 26 is narrower than a breadth W1 of the body portion 24.SELECTED DRAWING: Figure 5

Description

The present invention relates to a stator including a stator core.

For example, the stator core described in Patent Document 1 includes a plurality of split iron cores. Each split core has a tooth portion and a pair of core back portions. The pair of core back portions are disposed on both sides of the stator core in the circumferential direction relative to the teeth portion, and are connected to the teeth portion via a thin connection portion.

Further, the stator core described in Patent Document 2 includes a plurality of teeth cores and a plurality of core back cores. Each core-back core is disposed radially outward of the stator core with respect to one tooth core, and connects one tooth core to another tooth core disposed adjacent to one tooth core.

Patent No. 6207769 Patent No. 4405160

In the stator described in Patent Document 1, a pair of core back portions are connected to the tooth portions via thin connection portions. Therefore, since the teeth are restrained in the radial direction of the stator core with respect to the pair of core back parts, it is difficult to increase the roundness of the inner peripheral part of the stator core formed by the tips of the plurality of teeth. . In addition, since a pair of core back parts provided on the outer periphery of the stator core are fixed to the teeth part, the pre-shaped winding winding parts are applied from the radial outside of the stator core to the teeth parts. Impossible to assemble.

In the stator described in Patent Document 2, each core-back core is separate from the teeth core, so before each core-back core is assembled to the teeth core, the windings are shaped in advance. It is possible to assemble the rotating portion to the tooth core from the radially outer side of the stator core. However, after each core-back core is assembled to the teeth core, each core-back core is placed radially outward of the stator core with respect to the teeth core, so that the teeth core is restrained in the radial direction of the stator core. Therefore, it is difficult to increase the roundness of the inner peripheral portion of the stator core formed by the tip portions of the plurality of tooth cores.

The present invention has been made in view of the above-mentioned problems, and includes, as an example, a pre-shaped winding portion that can be assembled to teeth from the outside in the radial direction of the stator core, and that It is an object of the present invention to provide a stator that can improve the roundness of its peripheral portion.

The invention according to claim 1 is provided with a stator core, and the stator core includes a plurality of teeth arranged in an annular shape, and a plurality of teeth arranged separately from the plurality of teeth, and a plurality of teeth arranged between the plurality of teeth. a back yoke, each of the teeth being interposed between a main body portion extending radially inward of the stator core with respect to the plurality of back yokes, and adjacent back yokes of the plurality of back yokes. , a stator having connecting portions connected to the adjacent back yokes, the width of the connecting portion being narrower than the width of the main body portion.

In the invention according to claim 1, the stator core includes a plurality of teeth and a plurality of back yokes. The plurality of back yokes are separate from the plurality of teeth, and are respectively arranged between the plurality of teeth. Therefore, since the teeth can be moved in the radial direction of the stator core between the plurality of back yokes, the roundness of the inner peripheral portion of the stator core formed by the tips of the plurality of teeth can be increased.

Moreover, in the invention according to claim 1, each tooth has a main body portion and a connecting portion. The main body portion extends radially inward of the stator core with respect to the plurality of back yokes, and the connection portion is interposed between adjacent back yokes of the plurality of back yokes and is connected to each adjacent back yoke. It is connected. The width of the connecting portion is narrower than the width of the main body portion. Therefore, the pre-shaped wire winding portion can be assembled to the teeth (specifically, the main body portion) from the connection portion side.

According to a second aspect of the invention, in the stator according to the first aspect, the connecting portion is formed in a tapered shape whose width becomes narrower toward the inside in the radial direction of the stator core.

In the invention according to claim 2, the connecting portion is formed in a tapered shape whose width becomes narrower toward the inside in the radial direction of the stator core. Therefore, for example, if a plurality of teeth and a plurality of back yokes are arranged inside a ring member that is a component or jig of the stator, and the plurality of back yokes are compressed in the circumferential direction of the stator core by the ring member. In this case, the plurality of teeth move radially outward of the stator core due to a force acting between the tapered connecting portion and the back yoke. The plurality of teeth are positioned in the radial direction of the stator core by the plurality of teeth coming into contact with the inner circumferential surface of the ring member. Thereby, the roundness of the inner peripheral portion of the stator core formed by the tip portions of the plurality of teeth can be increased.

According to a third aspect of the invention, in the stator according to the second aspect, an angle at which a side surface of the connecting portion is inclined with respect to a central axis passing through the widthwise center of the teeth is θ, and the number of the plurality of teeth is This is a stator that satisfies equation (1), where n is the stator.
0°<θ<360°/2n...(1)

In the invention according to claim 3, when the angle at which the side surface of the connecting portion is inclined with respect to the central axis passing through the center of the teeth in the width direction is θ, and the number of the plurality of teeth is n, equation (1) is satisfied. To establish. Therefore, since the back yoke can be inserted between adjacent teeth from the radially outer side of the stator core, the ease of assembling the stator core can be improved.

The invention according to claim 4 is the stator according to claim 2, in which each of the teeth has a first outer peripheral part that forms the outer peripheral surface of the stator core, and each of the back yokes has a first outer peripheral part that forms the outer peripheral surface of the stator core. A stator having a second outer peripheral portion formed therein.

In the invention according to claim 4, each tooth has a first outer circumferential portion forming the outer circumferential surface of the stator core, and each back yoke has a second outer circumferential portion forming the outer circumferential surface of the stator core. Therefore, the plurality of teeth and the plurality of back yokes are positioned in the radial direction of the stator core by the first outer peripheral portion and the second outer peripheral portion coming into contact with the inner peripheral surface of the ring member. Thereby, the stator core can be annularized with high precision.

The invention according to claim 5 is the stator according to claim 4, which includes a ring member disposed on the radially outer side of the stator core, and the first outer circumferential portion and the second outer circumferential portion are arranged on the inner side of the ring member. The stator is in contact with the circumferential surface.

The invention according to claim 5 includes a ring member disposed radially outward with respect to the stator core, and the first outer circumferential portion and the second outer circumferential portion are in contact with the inner circumferential surface of the ring member. Therefore, the plurality of teeth and the plurality of back yokes can be positioned in the radial direction of the stator core by the ring member that is a component of the stator.

The invention according to claim 6 is the stator according to claim 5, wherein the stator core is press-fitted or shrink-fitted inside the ring member, and the plurality of back yokes are fitted around the stator core by the ring member. The stator is compressed in the direction.

In the invention according to claim 6, the stator core is press-fitted or shrink-fitted inside the ring member, and the plurality of back yokes are compressed in the circumferential direction of the stator core by the ring member. Therefore, the plurality of teeth move radially outward of the stator core due to the force acting between the tapered connecting portion and the back yoke. Thereby, the plurality of teeth can be positioned in the radial direction of the stator core by the plurality of teeth coming into contact with the inner circumferential surface of the ring member.

The invention according to claim 7 is the stator according to claim 1, in which each of the teeth and the adjacent back yokes are welded.

In the invention according to claim 7, each tooth and the adjacent back yoke are welded. Therefore, a stator core having a plurality of teeth and a plurality of back yokes can be held in an annular shape.

The invention according to claim 8 is the stator according to claim 1, wherein the plurality of teeth and the plurality of back yokes are each formed of an electromagnetic steel plate, and the rolling direction of the electromagnetic steel plate forming each of the teeth is are set in the radial direction of the stator core, and the rolling direction of the electromagnetic steel sheets forming each of the back yokes is set in the tangential direction of the stator core.

In the invention according to claim 8, the plurality of teeth and the plurality of back yokes are each formed of an electromagnetic steel plate. The rolling direction of the electromagnetic steel sheet forming each tooth is set in the radial direction of the stator core, and the rolling direction of the electromagnetic steel sheet forming each back yoke is set in the tangential direction of the stator core. Therefore, the teeth can efficiently pass magnetic flux in the radial direction of the stator core, and the back yoke can efficiently pass magnetic flux in the tangential direction of the stator core.

The invention according to claim 9 is the stator according to claim 1, which includes a plurality of wire winding portions respectively wound around the plurality of teeth, and each of the wire winding portions is shaped in advance. The stator is assembled to each of the teeth in this state.

In the invention according to claim 9, each winding portion is assembled to the teeth in a pre-shaped state. Therefore, it is possible to increase the space of the winding portion and improve the efficiency of the winding work.

The invention according to claim 10 is the stator according to claim 9, wherein a part of each of the winding portions on the back yoke side is in contact with the back yoke via an insulator.

In the invention according to claim 10, a part of each of the winding portions on the back yoke side is in contact with the back yoke via an insulator. Therefore, a portion of each of the wire winding portions on the back yoke side is disposed in the dead space, so that it is possible to realize a high occupancy of the wire winding portions.

FIG. 2 is a plan view showing an example of a motor. FIG. 3 is a plan view showing an example of a stator core. It is a perspective view showing an example of a stator core. FIG. 3 is a plan view showing an example of teeth and a back yoke. FIG. 7 is a plan view showing an example in which the tapered shape of the connecting portion is exaggerated. It is a top view which shows an example of a 1st outer peripheral part and a 2nd outer peripheral part. It is a top view which shows an example of the rolling direction of teeth and a back yoke. It is a top view which shows an example of the coil|winding winding part of the state wound around teeth. FIG. 7 is a plan view showing an example of a divided core according to a comparative example.

First, the configuration of the stator 10 according to an embodiment of the present invention will be described.

As shown in FIG. 1, a stator 10 according to an embodiment of the present invention is applied to a motor M. As shown in FIG. The motor M is an inner rotor type brushless motor and includes a stator 10 and a rotor 12.

The stator 10 has an annular configuration, and the rotor 12 is rotatably housed inside the stator 10. The stator 10 includes a stator core 14 , a plurality of wire windings 16 , and a ring member 18 . Stator core 14 includes multiple teeth 20 and multiple back yokes 22. The plurality of wire winding portions 16 are wound around the plurality of teeth 20, respectively. The winding wire used in the winding portion 16 may be either a round wire or a flat wire. Ring member 18 is arranged radially outward of stator core 14 . As an example, the ring member 18 is a ring-shaped yoke.

As shown in FIGS. 2 and 3, the plurality of teeth 20 are arranged in an annular shape along the circumferential direction of the stator core 14. As shown in FIGS. The plurality of back yokes 22 are separate from the plurality of teeth 20. The plurality of back yokes 22 are arranged between the plurality of teeth 20, respectively.

As shown in FIG. 4, each tooth 20 has a main body portion 24 and a connecting portion 26. As shown in FIG. The main body portion 24 extends radially inward of the stator core 14 with respect to the plurality of back yokes 22 . A portion of the teeth 20 that extends radially inward of the stator core 14 with respect to the back yoke 22 is the main body portion 24 . The connecting portion 26 is interposed between adjacent back yokes 22 of the plurality of back yokes 22. A portion of the teeth 20 that is interposed between adjacent back yokes 22 is a connecting portion 26 . The connecting portions 26 are connected to adjacent back yokes 22, respectively. Specifically, the connecting portions 26 are respectively connected to the adjacent back yokes 22 with side surfaces 26A on both sides of the connecting portions 26 overlapping the side surfaces 22A of each back yoke 22.

As shown in FIG. 5, the connecting portion 26 is formed in a tapered shape whose width becomes narrower toward the inside in the radial direction of the stator core 14. As shown in FIG. In FIG. 5, the taper angle of the connecting portion 26 is shown exaggerated with respect to FIG. The width W1 is the width of the main body portion 24. The width W2 is the width of the tapered connecting portion 26 at the end opposite to the main body portion 24, and is the maximum width of the connecting portion 26. The width W3 is the width of the end of the tapered connecting portion 26 on the main body portion 24 side, and is the minimum width of the connecting portion 26. As an example, the width W1 of the main body portion 24 is constant over the direction in which the main body portion 24 extends (that is, the radial direction of the stator core 14). The width W2 and the width W3 of the connecting portion 26 are narrower than the width W1 of the main body portion 24.

As shown in FIG. 4, the angle θ is an angle at which the side surface 26A of the connecting portion 26 is inclined with respect to the central axis L1 passing through the center of the teeth 20 in the width direction. The angle α is an angle at which the central axis L2 passing through the widthwise center of the back yoke 22 is inclined with respect to the central axis L1. The angle θ is set to be less than or equal to the angle α. Specifically, when the number of teeth 20 is n, formula (1) holds true in stator core 14. Note that in this embodiment, n=12, as an example.
0°<θ<360°/2n...(1)

As shown in FIG. 6, each tooth 20 has a first outer circumferential portion 28 forming the outer circumferential surface 14A of the stator core 14, and each back yoke 22 has a second outer circumferential portion forming the outer circumferential surface 14A of the stator core 14. 30. The connecting portion 26 has an outward facing surface 26B facing radially outward of the stator core 14, and the first outer peripheral portion 28 is formed by the outward facing surface 26B. The back yoke 22 also has an outward surface 22B that faces outward in the radial direction of the stator core 14, and the second outer peripheral portion 30 is formed by a central portion of the outward surface 22B protruding outward in the radial direction of the stator core 14. There is.

The first outer circumferential portion 28 and the second outer circumferential portion 30 are in contact with the inner circumferential surface 18A of the ring member 18. When the first outer circumferential portion 28 and the second outer circumferential portion 30 come into contact with the inner circumferential surface 18A of the ring member 18, the positions of the tip portions 20A of the plurality of teeth 20 and the position of the neutral line L3 of the plurality of back yokes 22 are adjusted. stipulated.

Specifically, the stator core 14 is press-fitted or shrink-fitted inside the ring member 18 , and the plurality of back yokes 22 are compressed by the ring member 18 in the circumferential direction of the stator core 14 . When the plurality of back yokes 22 are compressed in the circumferential direction of the stator core 14, the plurality of teeth 20 are moved radially outward of the stator core 14 due to the force acting between the tapered connecting portion 26 and the back yoke 22. Move to. The plurality of teeth 20 are positioned in the radial direction of the stator core 14 by the plurality of teeth 20 coming into contact with the inner circumferential surface 18A of the ring member 18.

As shown in FIG. 7, an insulator 32 is attached to the teeth 20, and an insulator 34 is attached to the back yoke 22. The insulator 32 is separate from the insulator 34. The insulator 32 is provided between the wire winding portion 16 and the teeth 20, and the insulator 34 is provided between the wire winding portion 16 and the back yoke 22.

As shown in FIG. 7, the plurality of teeth 20 and the plurality of back yokes 22 are each formed of an electromagnetic steel plate. Specifically, the plurality of teeth 20 and the plurality of back yokes 22 are each a laminate in which a plurality of electromagnetic steel plates are laminated. As an example, the rolling direction A1 of the electromagnetic steel sheet forming each tooth 20 is set in the radial direction of the stator core 14, and the rolling direction A2 of the electromagnetic steel sheet forming each back yoke 22 is set in the tangential direction of the stator core 14. has been done.

As shown in FIG. 8, each wire winding portion 16 is assembled to the teeth 20 from the connection portion 26 side in a previously shaped state. A portion 16A of each winding portion 16 on the back yoke 22 side is in contact with the back yoke 22 via an insulator 34. A portion 16A of each winding portion 16 on the back yoke 22 side is arranged in a so-called dead space 36.

Here, the dead space 36 will be explained. FIG. 9 shows a divided core 40 according to a comparative example. The split core 40 has teeth portions 42 and a pair of back yoke portions 44 . The pair of back yoke portions 44 extend from the ends of the teeth portions 42 on the outer peripheral side toward both sides of the stator core 14 in the circumferential direction. In the split core 40 according to the comparative example, a pair of back yoke parts 44 are integrally formed with the teeth part 42. Therefore, it is impossible to assemble the wire winding portion 46 that has been shaped in advance to the teeth portion 42 from the radially outer side of the stator core 14 . Therefore, in the split core 40 according to the comparative example, the wire winding portion 46 is formed by winding the wire around the teeth portion 42 using a winding machine (for example, a flyer).

When winding a wire around the teeth portion 42 using a winding machine, a flyer of the winding machine rotates around the central axis L4 of the teeth portion 42. Therefore, the winding is wound around the teeth portion 42 within a range where the winding does not interfere with the back yoke portion 44. Therefore, a gap is created between the winding winding part 46 and the back yoke part 44. This gap is a dead space 36. Specifically, the dead space 36 is formed between a boundary line L5 passing through a corner 44A on the inner peripheral side of the tip end of the back yoke portion 44 and orthogonal to the central axis L4 of the teeth portion 42, and an inward surface 44B of the back yoke portion 44. It is the space between.

Next, a method for manufacturing the stator 10 according to an embodiment of the present invention will be described.

In the method for manufacturing the stator 10 according to the embodiment of the present invention, the plurality of teeth 20 and the plurality of back yokes 22 are each equipped with an insulator 32 and an insulator 34, respectively. Next, the winding is wound into a coil shape or shaped after winding to form a winding winding part 16, and the winding winding part 16 is radially outward of the stator core 14 (i.e., on the connection part 26 side). It is assembled to each tooth 20 from the beginning. Note that, as an example, the winding portion 16 may be formed by directly winding the winding around the teeth portion 42 . Next, the plurality of teeth 20 are arranged in a ring. Next, the plurality of back yokes 22 are assembled to the plurality of teeth 20 from the radially outer side of the stator core 14 . Next, the stator core 14 is press-fitted or shrink-fitted inside the ring member 18 . The stator 10 is manufactured in the manner described above.

Next, the functions and effects of one embodiment of the present invention will be explained.

In the stator 10 according to one embodiment of the present invention, the stator core 14 includes a plurality of teeth 20 and a plurality of back yokes 22. The plurality of back yokes 22 are separate from the plurality of teeth 20 and are respectively arranged between the plurality of teeth 20. Therefore, since the teeth 20 can be moved in the radial direction of the stator core 14 between the plurality of back yokes 22, the roundness of the inner peripheral portion of the stator core 14 formed by the tip portions 20A of the plurality of teeth 20 is increased. be able to.

Furthermore, in the stator 10 according to one embodiment of the present invention, each tooth 20 includes a main body portion 24 and a connecting portion 26 . The main body portion 24 extends radially inward of the stator core 14 with respect to the plurality of back yokes 22, and the connection portion 26 is interposed between adjacent back yokes 22 of the plurality of back yokes 22, The back yokes 22 adjacent to each other are connected to each other. The width W2 of the connecting portion 26 is narrower than the width W1 of the main body portion 24. Therefore, the wire winding portion 16 that has been shaped in advance can be assembled to the teeth 20 (specifically, the main body portion 24) from the connection portion 26 side.

Furthermore, in the stator 10 according to the embodiment of the present invention, the connecting portion 26 is formed in a tapered shape whose width becomes narrower toward the inside in the radial direction of the stator core 14. Therefore, for example, in a state where a plurality of teeth 20 and a plurality of back yokes 22 are arranged inside a ring member 18 that is a component of the stator 10, the plurality of back yokes 22 are moved in the circumferential direction of the stator core 14 by the ring member 18. When compressed, the plurality of teeth 20 move radially outward of the stator core 14 due to the force acting between the tapered connecting portion 26 and the back yoke 22. Then, the plural teeth 20 are positioned in the radial direction of the stator core 14 by abutting the inner circumferential surface 18A of the ring member 18. Thereby, the roundness of the inner peripheral portion of the stator core 14 formed by the tip portions 20A of the plurality of teeth 20 can be increased.

In the stator 10 according to the embodiment of the present invention, the angle at which the side surface 26A of the connecting portion 26 is inclined with respect to the central axis L1 passing through the center of the teeth 20 in the width direction is θ, and the number of the plurality of teeth 20 is When n is set, the above formula (1) is established. Therefore, since the back yoke 22 can be inserted between the adjacent teeth 20 from the radially outer side of the stator core 14, the ease of assembling the stator core 14 can be improved.

Furthermore, in the stator 10 according to the embodiment of the present invention, each tooth 20 has a first outer circumferential portion 28 that forms an outer circumferential surface 14A of the stator core 14, and each back yoke 22 has a first outer circumferential portion 28 that forms an outer circumferential surface 14A of the stator core 14. It has a second outer peripheral portion 30 formed therein. Therefore, the plurality of teeth 20 and the plurality of back yokes 22 are positioned in the radial direction of the stator core 14 by the first outer circumferential portion 28 and the second outer circumferential portion 30 coming into contact with the inner circumferential surface 18A of the ring member 18 . Thereby, the stator core 14 can be annularized with high precision.

Further, the stator 10 according to an embodiment of the present invention includes a ring member 18 disposed radially outward with respect to the stator core 14, and the first outer circumferential portion 28 and the second outer circumferential portion 30 are arranged inside the ring member 18. It is in contact with the peripheral surface 18A. Therefore, the plurality of teeth 20 and the plurality of back yokes 22 can be positioned in the radial direction of the stator core 14 by the ring member 18 that is a component of the stator 10 .

Furthermore, in the stator 10 according to the embodiment of the present invention, the stator core 14 is press-fitted or shrink-fitted inside the ring member 18, and the plurality of back yokes 22 are compressed in the circumferential direction of the stator core 14 by the ring member 18. has been done. Therefore, the plurality of teeth 20 move radially outward of the stator core 14 due to the force acting between the tapered connecting portion 26 and the back yoke 22. Thereby, the plurality of teeth 20 can be positioned in the radial direction of the stator core 14 by abutting the inner circumferential surface 18A of the ring member 18.

Moreover, in the stator 10 according to an embodiment of the present invention, the plurality of teeth 20 and the plurality of back yokes 22 are each formed of an electromagnetic steel plate. The rolling direction A1 of the electromagnetic steel sheet forming each tooth 20 is set in the radial direction of the stator core 14, and the rolling direction A2 of the electromagnetic steel sheet forming each back yoke 22 is set in the tangential direction of the stator core 14. . Therefore, the teeth 20 can efficiently pass the magnetic flux in the radial direction of the stator core 14, and the back yoke 22 can efficiently pass the magnetic flux in the tangential direction of the stator core 14.

Furthermore, in the stator 10 according to an embodiment of the present invention, each winding portion 16 is assembled to the teeth 20 in a pre-shaped state. Therefore, it is possible to increase the space of the wire winding section 16 and improve the efficiency of the winding work.

Further, in the stator 10 according to the embodiment of the present invention, a portion 16A of each winding portion 16 on the back yoke 22 side is in contact with the back yoke 22 via the insulator 34. Therefore, a portion 16A of each wire winding portion 16 on the back yoke 22 side is disposed in the dead space 36, so that a high space area of the wire winding portion 16 can be realized.

Next, a modification of one embodiment of the present invention will be described.

In the above embodiment, the number of teeth 20 is 12, but may be other than 12.

Further, in the embodiment described above, the stator core 14 is held in an annular shape by the ring member 18 being arranged on the radially outer side of the stator core 14, but each tooth 20 and the adjacent back yoke 22 have a welded portion (not shown). (omitted) may be held in an annular shape. Further, the ring member 18 and the welded portion may be used together, but for example, when the ring member 18 is omitted, each tooth 20 and the adjacent back yoke 22 may be fixed by the welded portion. Furthermore, when the ring member 18 is omitted, each tooth 20 and the adjacent back yoke 22 are fixed by a welded portion while the stator core 14 is held annularly by an annular jig in place of the ring member 18, and each tooth 20 and the adjacent back yoke 22 are fixed by the welded portion, the jig may be removed from the stator core 14. In this way, when each tooth 20 and the adjacent back yoke 22 are welded by the welded portion, the stator core 14 having the plurality of teeth 20 and the plurality of back yokes 22 can be held in an annular shape by the welded portion.

Further, the welded portion may be formed across each tooth 20 and the adjacent back yoke 22, and the first welded portion that fixes each tooth 20 and one of the adjacent back yokes 22, and each tooth 20 It may be separated into a second welded portion that fixes the other of the adjacent back yokes 22.

Furthermore, when a welded portion is used, each tooth 20 and an adjacent back yoke 22 may be fixed by the welded portion in a state where the plurality of back yokes 22 are compressed in the circumferential direction of the stator core 14.

Further, the welded portion may be formed by any type of welding such as solder welding or laser welding. In the stator 10 according to an embodiment of the present invention, the connecting portion 26 is formed in a tapered shape whose width becomes narrower toward the inside in the radial direction of the stator core 14. Therefore, for example, when each tooth 20 and the adjacent back yoke 22 are laser welded from the radially outer side of the stator core 14, the laser light can be prevented from reaching the winding portion 16.

Further, in the above embodiment, the ring member 18 is a yoke, but it may be a member other than the yoke (for example, a motor housing, etc.). Further, the ring member 18 may be made of resin. Further, the ring member 18 may be a jig.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above, and it is of course possible to implement various modifications other than the above without departing from the spirit thereof. It is.

M...Motor, 10...Stator, 12...Rotor, 14...Stator core, 14A...Outer circumferential surface, 16...Winding winding part, 18...Ring member, 18A...Inner circumferential surface, 20...Teeth, 20A...Tip part, 22 ...Back yoke, 22A...Side surface, 22B...Outward surface, 24...Body portion, 26...Connection portion, 26A...Side surface, 26B...Outward surface, 28...First outer circumference, 30...Second outer circumference, 32...Insulator, 34...Insulator, 36...Dead space

Claims (10)

Equipped with a stator core,
The stator core is
Multiple teeth arranged in a ring,
a plurality of back yokes that are separate from the plurality of teeth and are respectively arranged between the plurality of teeth;
Equipped with
Each said tooth is
a main body portion extending radially inward of the stator core with respect to the plurality of back yokes;
a connecting portion interposed between adjacent back yokes of the plurality of back yokes and connected to each of the adjacent back yokes;
has
The width of the connecting portion is narrower than the width of the main body portion.
stator. The connecting portion is formed in a tapered shape whose width becomes narrower toward the inside in the radial direction of the stator core.
A stator according to claim 1. When the angle at which the side surface of the connecting portion is inclined with respect to the central axis passing through the center of the teeth in the width direction is θ, and the number of the plurality of teeth is n, equation (1) holds true.
0°<θ<360°/2n...(1)
A stator according to claim 2. Each of the teeth has a first outer peripheral portion forming an outer peripheral surface of the stator core,
Each of the back yokes has a second outer peripheral portion forming an outer peripheral surface of the stator core.
A stator according to claim 2. comprising a ring member disposed radially outward of the stator core,
The first outer peripheral part and the second outer peripheral part are in contact with the inner peripheral surface of the ring member,
A stator according to claim 4. The stator core is press-fitted or shrink-fitted inside the ring member,
The stator according to claim 5, wherein the plurality of back yokes are compressed in the circumferential direction of the stator core by the ring member. The stator according to claim 1, wherein each of the teeth and the adjacent back yoke are welded. The plurality of teeth and the plurality of back yokes are each formed of an electromagnetic steel plate,
The rolling direction of the electromagnetic steel sheet forming each of the teeth is set in the radial direction of the stator core,
The stator according to claim 1, wherein the rolling direction of the electromagnetic steel sheets forming each of the back yokes is set in a tangential direction of the stator core. comprising a plurality of wire winding portions respectively wound around the plurality of teeth,
Each of the wire winding portions is assembled to each of the teeth in a pre-shaped state,
A stator according to claim 1. A part of each of the winding portions on the back yoke side is in contact with the back yoke via an insulator.
A stator according to claim 9.