WO2022210714A1

WO2022210714A1 - Motor

Info

Publication number: WO2022210714A1
Application number: PCT/JP2022/015461
Authority: WO
Inventors: 智彰中野
Original assignee: ミネベアミツミ株式会社
Priority date: 2021-03-31
Filing date: 2022-03-29
Publication date: 2022-10-06
Also published as: JP2022155981A

Abstract

A motor (1) is provided with a shaft (99), a rotor (90), a first stator (3), and a second stator (4). The first stator (3) has a cylindrical yoke portion (11), and a plurality of first magnetic pole portions (12) formed integrally with the yoke portion (11). The second stator (4) has a plurality of second magnetic pole portions (22) capable of engaging with the first stator (3), and linking portions (21) linking one end side of each of the plurality of second magnetic pole portions (22) together.

Description

motor

The present invention relates to motors.

In a rotating electric machine such as a motor, there is known a technique of forming an annular stator core by combining split cores in order to improve the winding space factor of the stator or facilitate winding of the coil.

JP-A-10-4640 JP 2013-223414 A JP 2017-46381 A JP 2011-103733 A

When a stator core is configured by combining split cores, the roundness of the inner diameter of the stator (roundness at the tips of the magnetic pole portions (teeth) that protrude inward in the radial direction of the stator) may increase.

An object of one aspect is to provide a motor capable of reducing the roundness of the inner diameter of the stator.

In one aspect, a motor includes a shaft, a rotor, a first stator, and a second stator. The first stator has a cylindrical yoke portion and a plurality of first magnetic pole portions integrally formed with the yoke portion. The second stator has a plurality of second magnetic pole portions that can be engaged with the first stator, and a connecting portion that connects one end sides of the plurality of second magnetic pole portions.

According to one aspect, the roundness of the inner diameter of the stator can be reduced.

FIG. 1 is a top view showing an example of the motor in the first embodiment. FIG. FIG. 2 is a perspective view showing an example of a stator in the first embodiment; FIG. FIG. 3 is a perspective view showing an example of a first stator core in the first embodiment; FIG. FIG. 4 is a perspective view showing an example of a second stator core in the first embodiment. FIG. 5 is an exploded perspective view showing one example of the stator in the first embodiment. FIG. 6 is a cross-sectional view showing an example of the first stator core in the first embodiment. FIG. 7 is a perspective view showing an example of a second stator core in the first embodiment; FIG. FIG. 8 is a perspective view showing an example of a first stator core and a second stator core in the first embodiment; FIG. 9 is a cross-sectional view showing an example of a stator in the first embodiment; FIG. 10 is a bottom view showing one example of the stator in the first embodiment. FIG. 11 is a top view showing an example of the motor in the second embodiment. FIG. 12 is a perspective view showing one example of a stator according to the second embodiment. FIG. 13 is an exploded perspective view showing an example of a stator according to the second embodiment. FIG. 14 is a perspective view showing an example of a first stator core in the second embodiment; FIG. 15 is an enlarged perspective view showing an example of the first magnetic pole portion in the second embodiment. FIG. 16 is an enlarged perspective view showing an example of the first magnetic pole portion to which the outer insulator is attached according to the second embodiment. FIG. 17 is an enlarged perspective view showing an example of the first magnetic pole portion to which the inner insulator is attached according to the second embodiment. FIG. 18 is a perspective view showing an example of a second stator core in the second embodiment. FIG. 19 is an enlarged cross-sectional view showing an example of the motor in the second embodiment. FIG. 20A is a cross-sectional view showing an example of an inner insulator in the second embodiment; FIG. 20B is a cross-sectional view showing an example of an inner insulator in the second embodiment; FIG. 21A is an enlarged cross-sectional view showing an example of the first projection and the second projection when the first stator is inserted in the second embodiment. FIG. 21B is an enlarged cross-sectional view showing an example of the first protrusion and the second protrusion when the insertion of the first stator is completed in the second embodiment.

Below, embodiments of the motor disclosed in the present application will be described in detail based on the drawings. Note that the dimensional relationship of each element in the drawings, the ratio of each element, and the like may differ from reality. Even between the drawings, there are cases where portions with different dimensional relationships and ratios are included. In each drawing, in order to make the description easier to understand, a coordinate system may be illustrated in which the direction in which the shaft 99 extends, which will be described later, is the axial direction, and the direction in which the rotor 90 rotates is the circumferential direction.

(First embodiment)
FIG. 1 is a top view showing an example of the motor in the first embodiment. FIG. Motor 1 shown in FIG. 1 includes, for example, stator 2 , rotor 90 and shaft 99 . The motor 1 described in each embodiment is an inner rotor type brushless motor. A rotor 90 having, for example, a plurality of magnets 91 as components is arranged in the motor 1 . A rotating shaft (shaft) 99 is coupled to the rotor 90 . Also, the motor 1 is housed in, for example, a frame (not shown).

FIG. 2 is a perspective view showing an example of the stator in the first embodiment. As shown in FIGS. 1 and 2, the stator 2 in the first embodiment includes a first stator core 10, a second stator core 20, a plurality of pairs of

insulators

13 and 14, and a plurality of pairs of

insulators

23 and 24. , a plurality of first coils 31 , and a plurality of second coils 32 . In the following description, the insulators 13a to 13f may be used when the plurality of insulators 13 are distinguished from each other. The plurality of

insulators

14, 23 and 24, the plurality of first coils 31, and the plurality of second coils 32 may also be denoted similarly.

In the first embodiment, the insulator 13 is attached to the first stator core 10 from the negative side in the axial direction. Similarly, the insulator 14 is attached to the first stator core 10 from the positive side in the axial direction. FIG. 3 is a perspective view showing an example of a first stator core in the first embodiment; FIG. As shown in FIG. 3 , the first stator core 10 includes a yoke portion 11 and six first magnetic pole portions 12 . In the following, when the plurality of first magnetic pole portions 12 are distinguished and expressed, they may be referred to as first magnetic pole portions 12a to 12f, respectively.

The yoke portion 11 is a bottomless cylindrical member made of a magnetic material such as stainless steel or an electromagnetic steel plate. The six first magnetic pole portions 12 are formed integrally with the yoke portion 11 . The first magnetic pole portion 12 is a protrusion that protrudes radially inward from the inner peripheral surface side of the yoke portion 11 . As shown in FIG. 3, the first magnetic pole portion 12 in the first embodiment includes, for example, two ends protruding in the circumferential direction on the tip side (inner side in the radial direction).

The

insulators

13 and 14 are made of an insulating material such as resin. As shown in FIG. 3, the insulators 13a to 13f and the insulators 14a to 14f are attached to the corresponding first magnetic pole portions 12a to 12f from each axial direction. As shown in FIG. 2, the insulator 13 is mounted so as to protrude in the negative direction in the axial direction from the one end portion 11x of the yoke portion 11 in the axial direction. Similarly, the insulator 14 is mounted so as to protrude in the positive direction in the axial direction from the other end portion 11y of the yoke portion 11 in the axial direction. 1 and 2, the first magnetic pole portion 12 is covered with a pair of

insulators

13 and 14 and is not visible.

The first coils 31a to 31f are wound around the first magnetic pole portions 12a to 12f via insulators 13a to 13f and insulators 14a to 14f, respectively. The first coil 31 is formed by, for example, winding a round copper wire by nozzle winding. A pair of

insulators

13 and 14 are attached to the first stator core 10, and a first coil 31 is wound around the

insulators

13 and 14 to form the first stator 3. As shown in FIG.

FIG. 4 is a perspective view showing an example of the second stator core in the first embodiment. As shown in FIG. 4 , the second stator core 20 includes connecting portions 21 and six second magnetic pole portions 22 . In the following, when the plurality of second magnetic pole portions 22 are distinguished and expressed, they may be referred to as second magnetic pole portions 22a to 22f, respectively.

The connecting part 21 is an annular member made of a magnetic material such as stainless steel or electromagnetic steel plate. The six second magnetic pole portions 22 are protruding portions that are integrally formed by connecting to the connecting portion 21 and protrude inward in the radial direction. As shown in FIG. 4 , the second magnetic pole portion 22 in the first embodiment also has two ends protruding in the circumferential direction, for example, toward the distal end side (inner side in the radial direction), similarly to the first magnetic pole portion 12 . Prepare. In the first embodiment, the second magnetic pole portion 22 is formed so that the cross-sectional shape in the radial direction and the length in the axial direction are substantially the same as those of the first magnetic pole portion 12 . Note that the connecting portion 21 and the second magnetic pole portion 22 may be formed separately and connected to each other, and the material of the connecting portion 21 is not limited to a magnetic material.

The

insulators

23 and 24 are made of an insulating material such as resin. As shown in FIG. 4, the insulators 23a to 23f and the insulators 24a to 24f are attached to the corresponding second magnetic pole portions 22a to 22f from each axial direction. As shown in FIGS. 2 and 4, the insulator 23 is mounted so as to protrude in the negative direction in the axial direction from the one end 21x of the connecting portion 21 in the axial direction. Similarly, the insulator 24 is mounted so as to protrude in the positive direction in the axial direction from the other end 22y of the second magnetic pole portion 22 in the axial direction. 1 and 2, the second magnetic pole portion 22 is covered with a pair of

insulators

23 and 24 and is not visible. In the first embodiment, insulator 23 has substantially the same shape as insulator 13 and insulator 24 has substantially the same shape as insulator 14 .

The second coils 32a to 32f are wound around the second magnetic pole portions 22a to 22f via pairs of insulators 23a to 23f and insulators 24a to 24f, respectively. The second coil 32 is also wound by nozzle winding, for example. A pair of

insulators

23 and 24 are attached to the second stator core 20, and a second coil 32 is wound around the

insulators

23 and 24 to form the second stator 4. As shown in FIG.

In the first embodiment, each of the first magnetic pole portions 12 a to 12 f is formed integrally with the cylindrical yoke portion 11 . Moreover, each of the second magnetic pole portions 22 a to 22 f is formed integrally with the annular connecting portion 21 . As a result, the positional deviation of each magnetic pole portion is reduced as compared with the case where each independent magnetic pole portion is combined. Therefore, in the first stator core 10 and the second stator core 20, it is possible to easily reduce the circularity of the tip end side (inner side in the radial direction) of each magnetic pole portion, so that the efficiency of the motor 1 can be improved, Cogging torque can be easily reduced.

The stator 2 in the first embodiment is configured by combining the first stator 3 including the first stator core 10 shown in FIG. 3 and the second stator 4 including the second stator core 20 shown in FIG. FIG. 5 is an exploded perspective view showing one example of the stator in the first embodiment. As shown in FIG. 5, the stator 2 is formed by attaching the second stator 4 to the first stator 3 from the negative side in the axial direction. At that time, the second magnetic pole portion 22 of the second stator 4 is inserted into the gap between the two first magnetic pole portions 12 of the first stator 3 . In this case, the first coil 31 wound around the first magnetic pole portion 12 via the

insulators

13 and 14 and the second coil 32 wound around the second magnetic pole portion 22 via the

insulators

23 and 24 are adjacent to each other. For example, as shown in FIGS. 2 to 5, a second coil 32a is inserted between the

first coils

31a and 31b. In this case, the first coil 31a is arranged between the second coil 32f and the second coil 32a. The joining of the first stator 3 and the second stator 4 is performed, for example, by press-fitting the first stator core 10 and the second stator core 20, but is not limited to this, and may be joined by welding, adhesion, or the like.

As described above, in the first embodiment, the first coil 31 and the second coil 32 are wound before the first stator core 10 and the second stator core 20 are respectively combined. As a result, workability in winding the coil by nozzle winding, for example, can be improved, and the winding space factor can also be improved.

Also, in the first embodiment, the length in the axial direction of the first magnetic pole portion 12 is smaller than the length in the axial direction of the yoke portion 11, for example. In this case, as shown in FIG. 6, a gap G1 is formed between one axial end portion 11x of the yoke portion 11 and an axial end portion 12x corresponding to the one end portion of the first magnetic pole portion 12. be done.

FIG. 6 is a cross-sectional view showing an example of the first stator core in the first embodiment. FIG. 6 shows a cross section taken along line AA in FIG. As shown in FIG. 6, the other end portion 11y of the yoke portion 11 and the end portion 12y corresponding to the other end portion of the first magnetic pole portion 12 are substantially flush with each other. It is formed. That is, the axial length of the first magnetic pole portion 12 is shorter than the axial length of the yoke portion 11 by the gap G1.

In addition, as shown in FIGS. 3 and 6, a convex portion 16 that protrudes radially inward is formed on a part of the one end portion 11x of the yoke portion 11 in the axial direction. In addition, the convex part 16 is an example of an engaging part. Further, in the following, when the plurality of convex portions 16 are distinguished and expressed, they may be described as convex portions 16a to 16f, respectively.

In the first embodiment, the convex portion 16 is formed, for example, between two first magnetic pole portions 12 adjacent in the circumferential direction. For example, the convex portion 16a is formed between the first magnetic pole portion 12a and the first magnetic pole portion 12b, and the convex portion 16f is formed between the first magnetic pole portion 12f and the first magnetic pole portion 12a. .

Further, in the first embodiment, as shown in FIGS. 6 and 7, the connecting portion 21 of the second stator core 20 is formed with recesses 26a to 26f that engage with the projections 16a to 16f. FIG. 7 is a perspective view showing an example of a second stator core in the first embodiment; FIG. For example, the protrusions 16a of the first stator core 10 shown in FIGS. 3 and 6 engage with the recesses 26a of the second stator core 20 shown in FIG. At this time, the convex portion 16a and the concave portion 26a are formed such that the one ends 11x and 21x in the axial direction are substantially flush with each other, in other words, substantially flush with each other.

In the first embodiment, as shown in FIG. 7, a gap G2 is formed between one end portion 21x of the connecting portion 21 and an end portion 22x corresponding to the one end portion of the second magnetic pole portion 22. . In the first embodiment, the gap G2 is formed to have approximately the same size as the gap G1 formed in the first stator core 10 . That is, as shown in FIGS. 8 and 9, the end portion 12x of the first magnetic pole portion 12 and the end portion 22x of the second magnetic pole portion 22 are substantially at the same position in the axial direction. Further, in the first embodiment, the axial length of the second magnetic pole portions 22 is substantially the same as the axial length of the first magnetic pole portions 12 of the first stator core 10 . In this case, as will be described later, when the first stator 3 is joined to the second stator 4, the other end portion 22y of the second magnetic pole portion 22 is connected to the other end portion 11y of the yoke portion 11 of the first stator core 10, and the end portion 12y of the first magnetic pole portion 12, and the position in the axial direction is substantially the same.

FIG. 8 is a perspective view showing an example of the first stator core and the second stator core in the first embodiment. FIG. 9 is a cross-sectional view showing an example of a stator in the first embodiment; FIG. 9 shows a cross section taken along line BB in FIG. As shown in FIG. 8, one end portion 11x of the yoke portion 11 and one end portion 21x of the connecting portion 21 are arranged substantially on the same plane when the protrusions 16 and the recesses 26 are engaged with each other. . In other words, the one end portion 11x of the yoke portion 11 and the one end portion 21x of the connecting portion 21 are formed to be substantially flush with each other. Further, the end portion 12x of the first magnetic pole portion 12 and the end portion 22x of the second magnetic pole portion 22 are substantially at the same position in the axial direction. It is sufficient that the first magnetic pole portions 12 and the second magnetic pole portions 22 are aligned in the axial direction within a range that does not affect the rotation of the motor 1, and the gap G1 formed in the first stator core 10 and the The size of the gap G2 formed in the second stator core 20 may be different. In other words, the stator 2 may have a shape in which unevenness is generated on the end face in the axial direction.

Furthermore, in the first embodiment, as shown in FIG. 9, the axial length L1 of the first stator core 10 and the axial length L2 of the second stator core 20 are formed to be substantially the same. be. As a result, as shown in FIG. 10 , even on the positive axial side of the stator 2 , the other end 11 y of the yoke portion 11 of the first stator core 10 and the other end of the second magnetic pole portion 22 of the second stator core 20 are connected to each other. The portion 22y is formed substantially on the same plane, in other words, substantially flush with the portion 22y. FIG. 10 is a bottom view showing one example of the stator in the first embodiment. FIG. 10 is a view of the stator 2 viewed from the direction opposite to that of FIG. 1 (positive side in the axial direction). As shown in FIG. 10 , the first magnetic pole portion 12 of the first stator core 10 is inserted between two adjacent second magnetic pole portions 22 . With such a configuration, it is possible to secure the center-of-gravity balance of the stator 2 when the first stator core 10 and the second stator core 20 are combined.

As described above, the motor 1 in the first embodiment includes the shaft 99, the rotor 90, the first stator 3, and the second stator 4. The first stator 3 has a tubular yoke portion 11 and a plurality of first magnetic pole portions 12 integrally formed with the yoke portion 11 . The second stator 4 has a plurality of second magnetic pole portions 22 that can be engaged with the first stator 3 and a connecting portion 21 that connects portions of the plurality of second magnetic pole portions 22 on one end side. With such a configuration, the roundness of the inner diameter of the stator can be reduced.

(Second embodiment)
In the first embodiment, the first stator core 10 and the second stator core 20 each have six magnetic pole portions, but the number of magnetic pole portions is not limited to this. On the other hand, for example, when the number of magnetic pole portions of the stator core increases, it may become difficult to insert the second stator around which the second coil is wound into the first stator around which the first coil is wound. .

Therefore, in the second embodiment, a configuration in which the shape of the insulator is changed in order to facilitate the combination of the first stator and the second stator will be described. FIG. 11 is a top view showing an example of the motor in the second embodiment. FIG. 12 is a perspective view showing one example of a stator according to the second embodiment. FIG. 13 is an exploded perspective view showing an example of a stator according to the second embodiment. In addition, in each of the following embodiments and modifications, the same reference numerals are given to the same parts as the parts shown in the drawings described above, and overlapping explanations will be omitted.

As shown in FIGS. 11 and 12, the motor 1A in the second embodiment includes a stator 2A, a rotor 90 and a shaft 99, for example. The stator 2A, as shown in FIG. 13, includes a first stator 3A and a second stator 4A. The first stator 3</b>A is configured by attaching an outer insulator 67 , a bobbin coil 36 , and an inner insulator 68 to the first stator core 60 . The second stator 4</b>A is configured by attaching an outer insulator 77 , a bobbin coil 37 , and an inner insulator 78 to the second stator core 70 . The inner insulator 68 is an example of a first insulating member, and the inner insulator 78 is an example of a second insulating member. In the following, when the 12 outer insulators 67 are distinguished and expressed, they may be referred to as outer insulators 67a to 67l. The plurality of outer insulators 77, the plurality of bobbin coils 36 and 37, and the plurality of

inner insulators

68 and 78 may also be denoted similarly.

FIG. 14 is a perspective view showing an example of the first stator core in the second embodiment. As shown in FIG. 14, the first stator core 60 in the second embodiment includes a yoke portion 61 and twelve first magnetic pole portions 62a to 62l. Further, similarly to the first stator core 10, the yoke portion 61 of the first stator core 60 is also formed with convex portions 66a to 66l projecting radially inward. In the following, when the plurality of first magnetic pole portions 62a to 62l are expressed without distinction, they are simply referred to as the first magnetic pole portion 62, and when the plurality of convex portions 66a to 66l are expressed without distinction, , may be simply referred to as a convex portion 66 .

FIG. 15 is an enlarged perspective view showing an example of the first magnetic pole portion in the second embodiment. As shown in FIG. 15, the first magnetic pole portion 62 in the second embodiment differs from the first magnetic pole portion 12 in that, for example, the tip side (inner side in the radial direction: upward direction in FIG. 15) and the circumferential direction It has a shape with no protruding ends. Further, as shown in FIG. 15, between one axial end 61x of the yoke portion 61 in the second embodiment and an axial end 62x corresponding to the one end of the first magnetic pole portion 62, , a gap G1 is formed.

As shown in FIG. 14, outer insulators 67a to 67l, bobbin coils 36a to 36l, and inner insulators 68a to 68l are attached to the first magnetic pole portions 62a to 62l, respectively. FIG. 16 is an enlarged perspective view showing an example of the first magnetic pole portion to which the outer insulator is attached according to the second embodiment. 14 and 16, unlike the

insulators

13, 14, 23, or 24 in the first embodiment, the outer insulator 67 is arranged radially inward ( 16). The inner insulator 68 to which the bobbin coil 36 is attached is similarly attached.

Next, the bobbin coil 36 is attached to the inner insulator 68 . The bobbin coil 36 in the second embodiment is composed of, for example, pre-wound rectangular copper wire. The bobbin coil 36 has, for example, a substantially trapezoidal cross-sectional shape that tapers toward the inner diameter side of the stator 2A. The inner diameter of the bobbin coil 36 is formed to be slightly larger than the outer shape of the first magnetic pole portion 62, for example.

Next, the inner insulator 68 with the bobbin coil 36 attached is attached to the first magnetic pole portion 62 with the outer insulator 67 attached. FIG. 17 is an enlarged perspective view showing an example of the first magnetic pole portion to which the inner insulator is attached according to the second embodiment. As described above, the inner insulator 68 is inserted from the radially inner side (upward in FIG. 17). The outer insulator 67 and the inner insulator 68 prevent the bobbin coil 36 from coming off. The order of attaching the outer insulator, the bobbin coil, and the inner insulator to the first magnetic pole portion is not limited to this. The inner insulator may be attached in the order of attaching the first magnetic pole portion to which the bobbin coil and the outer insulator are attached. The same applies to the second magnetic pole portion, which will be described later.

As shown in FIG. 17, the inner insulator 68 includes a pair of

first protrusions

6L and 6R that protrude in the circumferential direction. The first projecting portion 6L engages with a second projecting portion 7R of an inner insulator 78, which will be described later. Similarly, the first protrusion 6R engages with a second protrusion 7L, which will be described later.

Next, the second stator 4A to which the inner insulator 78 is attached will be described. FIG. 18 is a perspective view showing an example of a second stator core in the second embodiment. As shown in FIG. 18, the second stator core 70 includes a connecting portion 71 and twelve second magnetic pole portions 72a to 72l. In the following, when the plurality of second magnetic pole portions 72a to 72l are expressed without distinguishing between them, they may simply be referred to as the second magnetic pole portions 72 in some cases.

In the second embodiment, the second magnetic pole portion 72 is formed so that the cross-sectional shape in the radial direction and the length in the axial direction are substantially the same as those of the first magnetic pole portion 62 . For example, as shown in FIG. 18, between one end portion 71x of the connecting portion 71 of the second stator core 70 and an end portion 72x corresponding to the one end portion of the second magnetic pole portion 72, the gap G1 has a size of A substantially identical gap G2 is formed. Further, as shown in FIG. 18, the second magnetic pole portion 72 also has a shape that does not have an end protruding in the circumferential direction on the tip side (inside in the radial direction), similarly to the first magnetic pole portion 62 . Similarly to the second stator core 20, the connecting portion 71 of the second stator core 70 is also formed with recesses 76a to 76l that engage with the protrusions 66a to 66l of the first stator core 60, respectively. It should be noted that when expressing the plurality of recesses 76a to 76l without distinguishing between them, they may simply be referred to as recesses 76 in some cases.

An outer insulator 77, a bobbin coil 37, and an inner insulator 78 are attached to the second magnetic pole portion 72 from the inside in the radial direction. In the second embodiment, the outer insulator 77 has substantially the same structure as the outer insulator 67, and the bobbin coil 37 has substantially the same structure as the bobbin coil 36, so detailed description thereof will be omitted.

Next, the inner insulator 78 with the bobbin coil 37 attached is attached to the second magnetic pole portion 72 with the outer insulator 77 attached. Like the outer insulator 67, the inner insulator 78 is also inserted from the inner side in the radial direction.

As shown in FIG. 18, the inner insulator 78 also includes a pair of

second protrusions

7L and 7R that protrude in the circumferential direction. Here, the engagement between the

first protrusions

6L and 6R and the

second protrusions

7L and 7R will be described. FIG. 19 is an enlarged cross-sectional view showing an example of the motor in the second embodiment. FIG. 19 is an enlarged view of the portion indicated by the frame F1 in FIG. In the motor 1A shown in FIG. 19, the

first protrusions

6L and 6R of the inner insulator 68 are engaged with the

second protrusions

7R and 7L of the adjacent inner insulator 78, respectively. For example, the first protrusion 6La of the inner insulator 68a engages the second protrusion 7Ra of the adjacent inner insulator 78a, and the first protrusion 6Ra of the inner insulator 68a engages the second protrusion of the adjacent inner insulator 78l. Engage with 7Ll. By engaging the first projecting portion and the second projecting portion in this manner, the coupling between the magnetic pole portions becomes stronger, so that rattling of the stator can be suppressed, and the bobbin coil 36, the outer insulator 67, the bobbin coil 36, the outer insulator 67, It is possible to prevent the inner insulator 68 from moving in the radial direction.

Further, at least one of the

first protrusions

6L and 6R and the

second protrusions

7L and 7R in the second embodiment may be tapered such that the thickness in the radial direction changes continuously. . For example, as shown in FIG. 17, the first protruding portion 6L of the inner insulator 68 is formed with a taper TP1 between the vicinity of the end portion on the negative side in the axial direction and the vicinity of the central portion in the axial direction. . By forming the taper TP1, the radial thickness of the first projecting portion 6L changes continuously with respect to the axial direction. For example, the thickness T3 near the negative end in the axial direction of the first projecting portion 6L is smaller than the thickness T4 near the positive end in the axial direction and near the central portion.

In the second embodiment, the first protrusion 6R of the inner insulator 68 is also tapered similarly to the taper TP1. As a result, the thickness T1 near the negative end in the axial direction of the first projecting portion 6R is also smaller than the thickness T2 near the positive end in the axial direction and near the central portion. 20A and 20B are cross-sectional views showing an example of the inner insulator in the second embodiment. 20A shows a cross section cut along line CC of FIG. 17, and FIG. 20B shows a cross section cut along line DD of FIG.

As shown in FIGS. 20A and 20B, the thickness T4 of the first projection 6L at the portion near the positive direction in the axial direction is greater than the thickness T4 of the first projection 6L at the portion near the negative direction in the axial direction. T3 is getting smaller. The same applies to the relationship between the thicknesses T2 and T1 of the first projecting portion 6R.

In the second embodiment, the

second protrusions

7R and 7L of the inner insulator 78 are also tapered. However, in the

second protrusions

7R and 7L, the tapered position and the direction in which the thickness changes in the radial direction are different from the taper TP1 formed in the first protrusion 6L. For example, as shown in FIG. 18, in the second projecting portion 7L, the thickness T6 near the end on the positive side in the axial direction is the thickness T6 near the end on the negative side in the axial direction and near the center. A taper is formed that is smaller than T5. That is, in the second protruding portion 7L, a taper TP2 is formed such that the thickness in the radial direction changes continuously from the vicinity of the central portion in the axial direction toward the end portion on the positive side in the axial direction. In the second embodiment, a similar taper is also formed on the second projecting portion 7R.

Thus, in the second embodiment, the thickness in the negative direction in the axial direction of the first projecting

portions

6L and 6R of the inner insulator 68 attached to the first stator 3A is reduced. In addition, the thickness in the positive direction in the axial direction is reduced in the second protruding

portions

7L and 7R of the inner insulator 78 attached to the second stator 4A. This makes it easy to mount the second stator 4A with the inner insulator 78 attached to the first stator 3A with the inner insulator 68 attached from the negative direction side in the axial direction.

FIG. 21A is an enlarged cross-sectional view showing an example of the first projecting portion and the second projecting portion when the first stator is inserted in the second embodiment. FIG. 21B is an enlarged cross-sectional view showing an example of the first protrusion and the second protrusion when the insertion of the first stator is completed in the second embodiment. When inserting the second stator 4A into the first stator 3A, the first protrusion 6R of the inner insulator 68 attached to the first stator 3A and the axially negative end portion of the first projection 6R of the inner insulator 68 are attached to the second stator 4A. The end of the second projecting portion 7L of the inner insulator 78 on the positive direction side in the axial direction approaches. In this case, as shown in FIG. 21A, the thickness T1 near the end of the first projecting portion 6R on the negative direction side and the thickness T6 near the end on the negative direction side of the second projecting portion 7L are small. A gap I is created between the first protrusion 6R and the second protrusion 7L. Due to the gap I, collision between the inner insulator 68 of the first stator 3A and the inner insulator 78 of the second stator 4A is less likely to occur, so workability is improved when inserting the first stator 3A into the second stator 4A. .

Further, when the insertion of the second stator 4A into the first stator 3A is completed, the thickness T2 of the first projecting portion 6R and the thickness T5 of the second projecting portion 7L increase, for example, near the central portion in the axial direction. As a result, the gap I between the first projecting portion 6R and the second projecting portion 7L is reduced. This suppresses rattling between the first stator 3A and the second stator 4A.

As described above, the first stator 3A of the motor 1A in the second embodiment includes the first insulating member 68, and the second stator 4A includes the second insulating member 78. The first insulating member 68 has

first protrusions

6L and 6R protruding in the inner diameter side in the circumferential direction, and the second insulating member 78 has

second protrusions

7L and 7R protruding in the inner diameter side in the circumferential direction. have Then, the first projecting portion 6R and the second projecting portion 7L are engaged. In addition, the radial thickness of the first projecting portion 6R is thinner on one axial end side than the axial direction other end side, and the radial thickness of the second projecting portion 7L is axially thinner than the axial direction one end side. It is thinner at the other end of the direction. With such a configuration, it is possible to improve workability when inserting the second stator 4A into the first stator 3A.

Although the configuration in each embodiment has been described above, the embodiment is not limited to these. For example, the number of first magnetic pole portions and second magnetic pole portions is not limited to those shown in each embodiment, and the number of first magnetic pole portions 12 and second magnetic pole portions 22 need not be the same.

Further, in the first embodiment, the tip portions (portions protruding inward in the radial direction) of the teeth (magnetic pole portions) 12 and 22 are provided with portions protruding in the circumferential direction, and in the second embodiment, the teeth (magnetic pole portions) (Parts) 62 and 72 have been described as having no portion protruding in the circumferential direction, but the embodiment is not limited to this. For example, in the first embodiment, the tip portion of the first magnetic pole portion 12 or the tip portion of the second magnetic pole portion 22 may be configured so as not to have a portion protruding in the circumferential direction. However, in the configuration using the bobbin coil as in the second embodiment, it is preferable that the configuration does not include a circumferentially projecting portion like the first magnetic pole portion 62 and the second magnetic pole portion 72 .

In the first embodiment, the insulator is attached to the stator core from the front and rear in the axial direction, and in the second embodiment, the insulator is attached to the stator core from the inner side in the radial direction with the coil interposed therebetween. is not limited to this. For example, in the first embodiment, the insulator may be attached to the stator core from the inside in the radial direction. However, when the insulators are attached from the front and rear in the axial direction, a gap is created between the front and rear insulators, so the insulators are likely to get caught when combining the first stator and the second stator. Therefore, when the number of magnetic pole portions is large as in the second embodiment, it is preferable to install the insulator from the inner side in the radial direction.

Further, in the second embodiment, the configuration in which the

protrusions

6L, 6R, 7L and 7R are formed at both ends of the

inner insulators

68 and 78 in the circumferential direction has been described, but the protrusions are provided only at one end. Alternatively, recesses may be provided instead of protrusions. However, in the case of forming a taper as shown in the second embodiment, it is preferable to form protrusions at both ends of the

inner insulators

68 and 78 in the circumferential direction. Note that the tapers TP1 and TP2 may be formed not only on one side in the axial direction but also over the entire axial direction. Note that the portion where the thickness in the radial direction changes continuously may be formed by a curved surface or the like instead of the inclined surface.

In addition, although the configuration in which the engaging portions of the first stator 3 and the second stator 4 are formed in the yoke portion 11 and the connecting portion 21 respectively has been described, the present invention is not limited to this, and the first magnetic pole portion 12 or the second stator 4 It may be formed in the magnetic pole portion 22 .

In each embodiment, it is described that the ends are arranged on substantially the same plane. Due to the above error, they may not be formed on the same plane. For example, there are cases where the lengths of the first stator and the second stator fluctuate within a range of ±5% of their respective axial lengths. Similarly, each member such as the first stator core and the second stator core may not have completely the same shape due to dimensional tolerances, etc., but there is no problem due to manufacturing errors within the scope of the effects of the present invention. .

Also, although the motor in each embodiment is, for example, an inner rotor type brushless motor, it is not limited to this, and the first stator and the second stator in the embodiment may be adopted in an outer rotor type motor. Also, the first stator and the second stator may be employed in rotating electric machines other than motors, such as generators.

As described above, the present invention has been described based on the embodiment and each modified example, but the present invention is not limited to the embodiment and each modified example, and various modifications can be made without departing from the gist of the present invention. It goes without saying that there is. Various modifications without departing from the gist of the invention are also included in the technical scope of the present invention, which will be apparent to those skilled in the art from the description of the claims.

1, 1A motor, 2, 2A stator, 3, 3A first stator, 4, 4A second stator, 10, 60 first stator core, 11, 61 yoke portion, 12 (12a to 12f), (62 (62a to 62l ) First magnetic pole portion (teeth), 13, 14, 23, 24 insulator, 16, 66 convex portion, 20, 70 second stator core, 21, 71 connecting portion, 22 (22a to 22f), 72 (72a to 72l) Second magnetic pole portion (teeth), 26, 76 concave portion, 31 first coil, 32 second coil, 36, 37 bobbin coil, 67, 77 outer insulator, 68, 78 inner insulator

Claims

a shaft;
a rotor;
a first stator;
a second stator;
The first stator has a cylindrical yoke portion and a plurality of first magnetic pole portions integrally formed with the yoke portion,
The second stator has a plurality of second magnetic pole portions that can be engaged with the first stator and a connecting portion,
The connecting portion connects the plurality of second magnetic pole portions at a portion on one end side in the axial direction.
3. The motor according to claim 1, wherein the first stator has an engaging portion that engages with the connecting portion of the second stator on the one end side.
At least part of the end surface of the first stator on the one end side and at least part of the end surface of the second stator on the one end side engaged with the first stator by the engaging portion are substantially coplanar. is placed in
3. The motor according to claim 2, wherein at least a portion of the end surface of the first stator on the other end side and at least a portion of the end surface of the second stator on the other end side are arranged substantially on the same plane.
The motor according to any one of claims 1 to 3, wherein the plurality of second magnetic pole portions are arranged between the plurality of first magnetic pole portions.
The first stator includes a first insulating member,
the second stator includes a second insulating member,
The first insulating member has a first projecting portion projecting in the circumferential direction on the inner diameter side,
The second insulating member has a second projecting portion projecting in the circumferential direction on the inner diameter side,
5. The motor according to any one of claims 1 to 4, wherein the first protrusion and the second protrusion are engaged.
the thickness of the first projecting portion in the radial direction is thinner on the one end side in the axial direction than on the other end side in the axial direction;
6. The motor according to claim 5, wherein the thickness of the second projecting portion in the radial direction is thinner on the other end side in the axial direction than on the one end side in the axial direction.
The motor according to claim 6, wherein a portion in which the thickness in the radial direction changes continuously is formed in either the first projecting portion or the second projecting portion.