CN115995906A

CN115995906A - Motor

Info

Publication number: CN115995906A
Application number: CN202211280146.7A
Authority: CN
Inventors: 高桥昌志
Original assignee: Nidec Sankyo Corp
Current assignee: Nidec Instruments Corp
Priority date: 2021-10-19
Filing date: 2022-10-19
Publication date: 2023-04-21
Also published as: JP2023061075A

Abstract

In a motor having a stator core formed by connecting split cores, the winding space factor is improved. The stator core of the motor is provided with salient poles on a plurality of divided cores arranged in the circumferential direction, and coils are wound around the salient poles. The first inner peripheral surface (41) of the winding slot (4) provided in the split core is a concave surface recessed radially outward. In the insulating member (5) for insulating the split core from the coil, a first portion (81) of insulating paper covering the first inner peripheral surface extends to a circumferential front end (Q1) of the first inner peripheral surface, whereas a circumferential front end (Q2) of an outer peripheral side covering portion (95) of the resin second insulating member (9) overlapped with the first portion of insulating paper is positioned closer to the salient pole (22) than the circumferential front end of the first inner peripheral surface. Therefore, the opening width of the winding slot is increased by the thickness of the outer peripheral side cover part, thereby avoiding the generation of space in the winding slot, which can not provide the coil wire (60), and improving the winding space factor.

Description

Motor

Technical Field

The present invention relates to a motor including stator cores formed by connecting split cores arranged in a circumferential direction, and coils wound around salient poles of the split cores via insulating members.

Background

In patent document 1, an inner rotor type motor in which a rotor is disposed on the inner peripheral side of a stator is disposed. In the motor of patent document 1, the stator includes: a stator core having a plurality of salient poles protruding toward an inner circumferential side; an insulator mounted to each salient pole; and a coil wound around each salient pole via an insulator. The stator core is formed by connecting a plurality of split cores in an annular shape. Each of the split cores includes an outer circumferential arc portion extending in the circumferential direction and salient poles protruding radially inward from the circumferential center of the outer circumferential arc portion, and an inner circumferential arc portion extending to both sides in the circumferential direction is provided at the tip of each salient pole. The space surrounded by the outer circular arc portion, the salient pole, and the inner circular arc portion forms a winding slot in which the coil is disposed.

In patent document 1, coils wound around respective salient poles are insulated from split cores by an insulating member covering the inner peripheral surface of a winding slot. The insulating member is provided with: an insulating paper inserted into the winding slot and covering the inner peripheral surface of the winding slot; and an insulator covering the split cores from above the insulating paper. Insulators are disposed at both ends of the split cores in the rotation axis direction.

Prior art literature

Patent literature

Patent document 1: japanese patent application laid-open No. 2010-45868

Disclosure of Invention

The present inventors studied to increase the number of turns of a coil wire and to increase the winding space factor in order to achieve high efficiency of a motor. Fig. 6 is a cross-sectional view schematically showing the structure of a split core, an insulating member, and a coil of the conventional example, which are cut through a plane orthogonal to the rotation axis. As shown in fig. 6, in the conventional example, an insulating paper 73 and an insulator 71 are stacked on the inner peripheral surface of the winding slot S provided on both sides in the circumferential direction of the salient pole 51, and the insulating members (the insulator 71 and the insulating paper 73) are arranged in two layers. Therefore, the internal space of the winding slot S is narrowed, and the number of turns of the coil wire cannot be increased.

Here, in the split core 50 of the conventional example shown in fig. 6, the inner peripheral surface of the outer peripheral side circular arc portion 53 surrounding the outer peripheral side of the winding slot S coincides with the virtual plane R orthogonal to the salient pole center line P. Here, if the inner peripheral surface of the outer peripheral arc portion 53 is formed as a concave surface R1 recessed toward the outer peripheral side than the virtual surface R as indicated by a broken line, the winding groove S spreads toward the outer peripheral side. Therefore, if the coil wire can be accommodated in the enlarged space, the number of turns of the coil wire can be increased without increasing the outer shape of the split core 50.

However, when the coil 6 is wound around the salient pole 51 using an automatic winding machine, the nozzle for supplying the coil wire is disposed in the circumferential opening of the winding slot S, and the split cores 50 are rotated about the salient pole center line P. Therefore, the coil wire supplied from the wire nozzle reaches only the position radially inward of the virtual plane R defining the opening of the winding slot S, and therefore the coil wire is not supplied to the position radially outward of the virtual plane R. Therefore, the number of turns of the coil wire cannot be increased.

In view of the above, an object of the present invention is to improve the winding space factor and the motor efficiency in a motor including a stator in which coils are wound around salient poles of split cores via insulating members.

In order to solve the above problems, a motor according to the present invention includes: a stator having a stator core including a plurality of salient poles arranged radially, and a coil wound around the salient poles via an insulating member; and a rotor disposed on an inner peripheral side of the stator, wherein the stator core includes a plurality of split cores arranged in a circumferential direction, and the split cores include: a split core outer peripheral portion extending in a circumferential direction; the salient poles extending radially inward from a circumferential center of the split core outer circumferential portion; and a split core inner peripheral portion extending from a front end of the salient pole to both sides in a circumferential direction, wherein winding slots surrounded by the split core outer peripheral portion, the salient pole, and the split core inner peripheral portion are provided on both sides in the circumferential direction of the salient pole, wherein an inner peripheral surface of the winding slots is provided with a first inner peripheral surface constituted by the split core outer peripheral portion, the first inner peripheral surface is a concave surface recessed radially outward, the insulating member is provided with a first insulating member covering the inner peripheral surface of the winding slots and a second insulating member overlapping the first insulating member, the first insulating member is provided with a first covering portion covering the first inner peripheral surface, the second insulating member is provided with a second covering portion overlapping the first covering portion, and a front end in the circumferential direction of the second covering portion is located closer to the salient pole side than the front end in the circumferential direction of the first inner peripheral surface.

According to the present invention, the radially outer inner peripheral surface (first inner peripheral surface) of the inner peripheral surfaces of the winding grooves is a concave surface recessed radially outward. Further, among the insulating members covering the inner peripheral surfaces of the winding slots, the circumferential front end of the layer (second covering portion) of the second insulating member overlapping the first insulating member is located on the salient pole side than the circumferential front end of the layer (first covering portion) of the first insulating member covering the first inner peripheral surface. By shortening the circumferential length of the layer (second covering portion) of the second insulating member in this way, the opening width of the winding slot is widened radially outward by the thickness of the second insulating member. Therefore, even when the split core is rotated to wind the coil wire, the coil wire can be provided in a space which is formed in a concave shape and is enlarged by forming the first inner peripheral surface from the opening side of the winding groove. Thus, the radial thickness of the outer peripheral portion of the split core can be ensured without increasing the outer shape of the split core, and the number of turns of the coil wire housed in the winding slot can be increased. Accordingly, the winding duty ratio is improved and the efficiency of the motor is improved.

In the present invention, it is preferable that the inner peripheral surface of the second covering portion is disposed on the same plane as a virtual plane orthogonal to a salient pole center line extending in the radial direction through a circumferential center of the salient pole and passing through a circumferential front end of the inner peripheral surface of the first covering portion, or is disposed on a radially inner side than the virtual plane. In this way, the second cover portion of the insulating member can be configured to protrude inward beyond the edge of the opening of the winding slot or to be positioned at the same location as the edge of the opening. Therefore, it is possible to avoid a space in the winding slot where the coil wire cannot be provided, and to increase the number of turns of the coil wire.

In the present invention, it is preferable that the first inner peripheral surface is an arc surface centered on the rotation axis of the rotor. Thus, the radial thickness of the outer peripheral portion of the split core can be ensured without increasing the outer shape of the split core, and the winding slots can be made widest.

In the present invention, the following structure can be adopted: the first inner peripheral surface is a bent surface having a first planar portion extending from the salient pole in a direction orthogonal to a salient pole center line passing through a circumferential center of the salient pole and extending in a radial direction, and a second planar portion bent with respect to the first planar portion and extending to a circumferential front end of the first inner peripheral surface. In this way, when the concave surface is a curved surface, the manufacturing is easier than the case of forming the concave surface as a curved surface. Therefore, the split core is easily manufactured. In addition, in the case where the second insulating member is made of resin, the second insulating member is also easy to manufacture.

In the present invention, it is preferable that the radial thickness of the circumferential front end of the divided core outer circumferential portion is 50% or more of the circumferential thickness of the salient pole. Thus, a necessary thickness of the outer peripheral portion of the split core can be ensured.

In the present invention, the following structure can be adopted: the stator core extends in the rotation axis direction of the rotor, the first insulating member is an insulating sheet covering the entire rotation axis direction of the inner peripheral surface of the winding slot, and the second insulating member includes: a first insulator made of resin, which covers an end portion of the split core on one side in the rotation axis direction; and a second insulator made of resin, which covers the other end of the split core in the rotation axis direction. In this way, since the insulating sheet is inserted into the winding slot and then the resin insulator is attached to each of the one side and the other side in the rotation axis direction, the work of assembling the split core and the insulating member is easy. Further, since the gap of the insulator can be covered with the insulating sheet, the split iron core can be easily assembled, and the split iron core and the coil can be reliably insulated.

Effects of the invention

Drawings

Fig. 1 is a sectional view of a motor of the present invention taken in a plane containing a rotation axis, and a sectional view schematically showing a structure taken in a plane orthogonal to the rotation axis.

Fig. 2 is a perspective view of the split core, the insulating member, and the coil.

Fig. 3 is an exploded perspective view of the split core and the insulating member.

Fig. 4 is a sectional view schematically showing a structure in which the core, the insulating member, and the coil are cut by a plane orthogonal to the rotation axis.

Fig. 5 is a cross-sectional view showing the opening width of the winding slot when winding the coil.

Fig. 6 is a cross-sectional view schematically showing the structure of a split core, an insulating member, and a coil of the conventional example, which are cut through a plane orthogonal to the rotation axis.

Detailed Description

Hereinafter, an embodiment of a motor to which the present invention is applied will be described with reference to the drawings. Fig. 1 (a) is a sectional view of the motor 1 of the present invention cut through a plane including the rotation axis L, and fig. 1 (b) is a sectional view schematically showing a structure of the motor 1 cut through a plane orthogonal to the rotation axis L. In the present specification, a direction along the rotation axis L of the motor 1 is referred to as a rotation axis direction. Among the one side and the other side in the rotation axis direction, the side on which the output shaft 2 protrudes is referred to as an output side L1, and the side opposite to the side on which the output shaft 2 protrudes is referred to as an opposite output side L2.

(integral structure)

The motor 1 of the present embodiment is a three-phase inner rotor type dc brushless motor. As shown in fig. 1 (a) and 1 (b), the motor 1 includes a motor case 10, an annular stator 20 disposed inside the motor case 10, and a rotor 30 rotatably disposed inside the stator 20. The motor housing 10 includes: a cylindrical portion 11 having both ends in the rotation axis direction as open ends; a first bearing housing 12 fixed to an end of the output side L1 of the cylindrical portion 11; and a second bearing housing 13 fixed to an end of the cylindrical portion 11 on the opposite output side L2. An outer race of the first bearing 14, which is formed of a ball bearing, is held in the inner portion Zhou Cebao of the first bearing housing 12. Further, an outer ring of the second bearing 15 constituted by a ball bearing is held in the inner portion Zhou Cebao of the second bearing 13. An encoder cover 16 is attached to the reverse output side L2 of the second bearing 13, and an encoder, not shown, is disposed inside the encoder cover 16. The encoder detects the rotational speed and angular position of the rotor 30.

The stator 20 is fixed inside the cylindrical portion 11. The stator 20 includes: an annular stator core 21 having a plurality of salient poles 22 protruding radially inward at equal angular intervals; and coils 6 wound around the salient poles 22 of the stator core 21 via the insulating members 5. The coil 6 is connected to a wiring board 7 disposed at an end of the stator core 21. A power supply line, not shown, is connected to the wiring board 7. The coil 6 is supplied with electric power via the power supply line and the wiring board 7.

The rotor 30 includes: a rotation shaft 31 extending in the rotation axis direction at the radial center of the stator 20; and a rotor magnet 32 fixed to the outer peripheral surface of the rotary shaft 31. The rotation shaft 31 is rotatably supported by the first bearing 14 and the second bearing 15. The rotation shaft 31 protrudes toward the output side L1 and the opposite output side L2 of the rotor magnet 32. An output shaft 2 protruding from the first bearing housing 12 is provided at an end of the output side L1 of the rotary shaft 31.

(split core)

Fig. 2 is a perspective view of the split core 3, the insulating member 5, and the coil 6, with a midway portion in the rotation axis direction omitted. Fig. 3 is an exploded perspective view of the split core 3 and the insulating member 5, and is a view in which a midway portion in the rotation axis direction is omitted. Fig. 4 is a sectional view of the core 3, the insulating member 5, and the coil 6 cut through a plane orthogonal to the rotation axis. As shown in fig. 1 (a), the stator core 21 is constituted by a laminated core in which a plurality of magnetic plates are laminated in the rotation axis direction. As shown in fig. 1 (b), the stator core 21 is formed by connecting a plurality of divided cores 3 arranged in the circumferential direction in a circular shape. In the present embodiment, the number of split cores 3 is 9.

As shown in fig. 3 and 4, the split core 3 includes: a split core outer peripheral portion 23 extending in the circumferential direction; salient poles 22 protruding radially inward from the center in the circumferential direction of the split core outer peripheral portion 23; and split core inner peripheral portions 24 extending from the front ends of the salient poles 22 to both sides in the circumferential direction. The inner peripheral surface of the split core inner peripheral portion 24 is an arc surface, and faces the outer peripheral surface of the rotor magnet 32 with a predetermined gap therebetween in the radial direction (see fig. 1 (b)). As shown in fig. 5, winding slots 4 are provided on each of the split cores 3 on both sides in the circumferential direction of the salient poles 22. The winding slots 4 are recesses surrounded by the split core outer circumferential portion 23, the salient poles 22, and the split core inner circumferential portion 24. The winding slots 4 are open on the opposite side of the salient poles 22 in the circumferential direction, and open on both sides in the rotation axis direction. The coil 6 wound around the salient pole 22 is housed in the winding slot 4.

The inner peripheral surface of the winding slot 4 includes a first inner peripheral surface 41 formed by the split core outer peripheral portion 23, a second inner peripheral surface 42 formed by the circumferential side surfaces of the salient poles 22, and a third inner peripheral surface 43 formed by the split core inner peripheral portion 24. The second inner circumferential surface 42 is a plane parallel to a salient pole center line P (see fig. 5) passing through the circumferential center of the salient pole 22 and extending in the radial direction. The first inner peripheral surface 41 is a curved surface that is curved midway in the circumferential direction, and is a concave surface that is recessed radially outward. By forming the first inner circumferential surface 41 as a concave surface, the radial thickness T (see fig. 4) at both circumferential ends of the split core outer circumferential portion 23 can be ensured without increasing the radial dimension of the split core 3. In the present embodiment, the radial thickness T of the both ends in the circumferential direction of the split core outer circumferential portion 23 is 50% or more of the circumferential thickness T0 of the salient pole 22. More specifically, it is preferable that the radial thickness T of the circumferential ends of the split core outer circumferential portion 23 is 50% or more and 60% or less of the circumferential thickness T0 of the salient pole 22.

As shown in fig. 3 and 4, the first inner peripheral surface 41 of the winding slot 4 includes a first flat surface portion 44 extending from an end portion of the second inner peripheral surface 42 on the radial outer side in a direction orthogonal to the salient pole center line P, and a second flat surface portion 45 inclined with respect to the first flat surface portion 44. The second flat surface portion 45 extends to the circumferential front end Q1 of the first inner circumferential surface 41. The third inner peripheral surface 43 extends circumferentially from the radially inner end of the second inner peripheral surface 42, and is an inclined surface that is inclined in the radially inner direction as it moves away from the salient poles 22 in the circumferential direction.

(insulating part)

The insulating member 5 covers the end face in the rotation axis direction of the split core 3 and covers the inner peripheral surface of the winding slot 4. In the present embodiment, as the insulating member 5, a first insulating member 8 made of an insulating sheet such as Nomex (Nomex) paper and a second insulating member 9 made of resin are provided. As shown in fig. 4, the first insulating member 8 and the second insulating member 9 are overlapped in two layers on the inner peripheral surface of the winding slot 4.

As shown in fig. 2, 3, and 4, in the present embodiment, as the first insulating member 8, a first insulating paper 8A disposed on one side in the circumferential direction of the salient pole 22 and a second insulating paper 8B disposed on the other side in the circumferential direction of the salient pole 22 are provided. The first insulating paper 8A and the second insulating paper 8B have the same structure. The first insulating paper 8A and the second insulating paper 8B cover the entire range in the rotation axis direction of the inner peripheral surface of the winding slot 4, respectively.

The first insulating paper 8A and the second insulating paper 8B each include an insulating paper first portion 81 covering the first inner peripheral surface 41 formed by the divided core outer peripheral portion 23, an insulating paper second portion 82 covering the second inner peripheral surface 42 formed by the salient poles 22, and an insulating paper third portion 83 covering the third inner peripheral surface 43 formed by the divided core inner peripheral portion 24, and these portions are in contact with the inner peripheral surfaces of the winding slots 4.

The first insulating paper 8A and the second insulating paper 8B are provided with a first bent portion 84 and a second bent portion 85, respectively, which are bent in the radial direction so as to block the circumferential opening 40 (see fig. 4) of the winding slot 4. The first bent portion 84 extends radially inward from a circumferential front end (i.e., an end edge on the opposite side from the salient pole 22) of the insulating paper first portion 81. The second bending portion 85 extends radially outward from a circumferential front end (i.e., an end edge on the opposite side from the salient pole 22) of the insulating paper third portion 83. The tip of the first bending portion 84 and the tip of the second bending portion 85 face each other with a predetermined gap. The first bent portion 84 and the second bent portion 85 cover the coil 6 disposed in the winding slot 4 from the side opposite to the salient pole 22.

As shown in fig. 2 and 3, in the present embodiment, the second insulating member 9 includes: a resin first insulator 9A fixed to an end portion of one side (output side L1) of the split core 3 in the rotation axis direction; and a resin second insulator 9B fixed to the end portion of the other side (the opposite output side L2) of the split core 3 in the rotation axis direction.

The first insulator 9A and the second insulator 9B are formed in the same structure and are disposed in the opposite direction to the rotation axis direction. The first insulator 9A and the second insulator 9B each include: a salient-pole end surface covering portion 91 that covers an end surface of the salient pole 22 in the rotation axis direction; an outer peripheral flange portion 92 that covers an end surface of the split core outer peripheral portion 23 in the rotation axis direction on the radial outer side of the salient pole end surface cover portion 91; and an inner peripheral flange 93 that covers an end surface of the split core inner peripheral portion 24 in the rotation axis direction on the radial inner side of the salient pole end surface cover 91. The outer peripheral flange 92 and the inner peripheral flange 93 protrude in the rotation axis direction on both sides in the radial direction of the salient pole end surface covering portion 91, and the coil 6 is wound between the outer peripheral flange 92 and the inner peripheral flange 93.

The first insulator 9A and the second insulator 9B each include: a salient pole side surface covering portion 94 that covers a circumferential side surface of the salient pole 22; an outer circumferential side cover portion 95 that extends in the circumferential direction from an end edge of the salient pole side cover portion 94 on the radially outer side and covers the first inner circumferential surface 41 of the winding slot 4; and an inner peripheral side cover portion 96 that extends in the circumferential direction from the radially inner end edge of the salient pole side cover portion 94 and covers the third inner peripheral surface 43 of the winding slot 4. The outer peripheral side cover 95, the salient pole side cover 94, and the inner peripheral side cover 96 overlap with the end portions of the first insulating sheet 8A or the second insulating sheet 8B in the rotation axis direction, and cover the inner peripheral surfaces of the winding slots 4 with the first insulating sheet 8A or the second insulating sheet 8B interposed therebetween.

As shown in fig. 2 and 3, the insulating paper first portion 81 and the insulating paper third portion 83 of the first insulating paper 8A and the second insulating paper 8B are longer than the lengths of the split cores 3 in the rotation axis direction, and protrude from the winding slots 4 to one side and the other side in the rotation axis direction. The outer peripheral flange portions 92 of the first insulator 9A and the second insulator 9B are provided with groove portions 97, and the groove portions 97 receive the insulating paper first portions 81 protruding from the winding grooves 4 in the rotation axis direction. Further, a recess 98 is provided in the inner peripheral flange 93, and the recess 98 accommodates the insulating paper third portion 83 protruding from the winding groove 4 in the rotation axis direction.

Next, the structure of the insulating member 5 covering the first inner peripheral surface 41 of the winding groove 4 will be described with reference to fig. 5. Fig. 4 shows a cross-sectional structure cut at a position where the first insulator 9A is attached, but the same cross-sectional structure is also applied at a position where the second insulator 9B is attached. As shown in fig. 5, the first inner peripheral surface 41 of the winding slot 4 provided on one side in the circumferential direction of the salient pole 22 is covered with the insulating paper first portion 81 of the first insulating paper 8A and the outer peripheral side covering portion 95 of the first insulator 9A. The first inner peripheral surface 41 of the winding slot 4 provided on the other side in the circumferential direction of the salient pole 22 is also covered with the insulating paper first portion 81 of the second insulating paper 8B and the outer peripheral side covering portion 95 of the first insulator 9A. That is, the first inner peripheral surface 41 of the winding slot 4 is covered with the insulating paper first portion 81 as the first covering portion and the outer peripheral side covering portion 95 as the second covering portion overlapping the insulating paper first portion 81.

As shown in fig. 5, in the present embodiment, the insulating paper first portion 81 extends to the circumferential front end Q1 of the first inner peripheral surface 41, and the insulating paper first portion 81 covers the entire circumferential first inner peripheral surface 41, whereas the circumferential front end Q0 of the outer peripheral side cover 95 of the first insulator 9A is located closer to the salient pole 22 than the circumferential front end Q1 of the first inner peripheral surface 41. More specifically, the circumferential tip Q0 of the outer peripheral side cover 95 is located in the vicinity of the bending point connecting the first planar portion 44 and the second planar portion 45 of the first inner peripheral surface 41. Therefore, the first flat surface portion 44 of the first inner peripheral surface 41 is covered with 2 layers of insulating paper (insulating paper first portion 81) and a resin member (outer peripheral side covering portion 95), and the second flat surface portion 45 is covered with only insulating paper (insulating paper first portion 81).

(opening width of winding slot)

Fig. 5 is a cross-sectional view schematically showing the opening width of the winding slot 4 when the coil 6 is wound. As shown in fig. 5, when the split core 3 is rotated around the salient pole center line P to wind the coil 6, the first insulating paper 8A and the second insulating paper 8B are wound in a state in which the first bending portion 84 and the second bending portion 85 are not bent in the radial direction but extend in the circumferential direction. At this time, the coil wire 60 is supplied from a nozzle (not shown) disposed in the circumferential opening 40 of the winding slot 4. In the present embodiment, since the outer peripheral side cover 95 does not extend to the circumferential front end Q1 of the first inner peripheral surface 41, the opening width D of the circumferential opening 40 of the winding slot 4 is increased by the plate thickness of the outer peripheral side cover 95.

As shown in fig. 5, the coil wire 60 can be supplied from the nozzle disposed in the opening 40 to a radial inner side than a virtual plane R passing through a circumferential tip Q2 of the inner peripheral surface of the insulating paper first portion 81 defining the opening width D and orthogonal to the salient pole center line P. In the present embodiment, the plate thickness of the outer peripheral side cover 95 is the same as the depth of the recess of the first inner peripheral surface 41, which is a concave surface, and therefore, the inner peripheral surface 950 of the outer peripheral side cover 95 is located on the same plane as the virtual plane R. Therefore, the coil wire 60 can be provided from the opening 40 to the entire range of the winding slot.

(main effects of the present embodiment)

The motor 1 of the present embodiment includes a stator 20 and a rotor 30, the stator 20 includes a stator core 21 and a coil 6, the stator core 21 includes a plurality of salient poles 22 arranged radially, the coil 6 is wound around the salient poles 22 via an insulating member 5, and the rotor 30 is arranged on an inner peripheral side of the stator 20. The stator core 21 includes a plurality of split cores 3 arranged in the circumferential direction, the split cores 3 include split core outer circumferential portions 23 extending in the circumferential direction, salient poles 22 extending radially inward from the circumferential center of the split core outer circumferential portions 23, and split core inner circumferential portions 24 extending from the tips of the salient poles 22 to both circumferential sides, and winding slots 4 surrounded by the split core outer circumferential portions 23, the salient poles 22, and the split core inner circumferential portions 24 are provided on both circumferential sides of the salient poles 22. The inner peripheral surface of the winding slot 4 includes a first inner peripheral surface 41 formed by the divided core outer peripheral portion 23, and the first inner peripheral surface 41 is a concave surface recessed radially outward. The insulating member 5 includes a first insulating member 8 (first insulating paper 8A or second insulating paper 8B) covering the inner peripheral surface of the winding slot 4, and a second insulating member 9 (first insulator 9A or second insulator 9B) overlapping the first insulating member 8. The first insulating member 8 includes an insulating paper first portion 81 (first covering portion) covering the first inner peripheral surface 41, and the second insulating member 9 includes an outer peripheral side covering portion 95 (second covering portion) overlapping the insulating paper first portion 81. The insulating paper first portion 81 extends to the circumferential front end Q1 of the first inner peripheral surface 41, whereas the circumferential front end Q0 of the outer peripheral side cover 95 is located closer to the salient pole 22 than the circumferential front end Q1 of the first inner peripheral surface 41.

In the present embodiment, the radially outer inner peripheral surface (first inner peripheral surface 41) of the inner peripheral surfaces of the winding grooves 4 is recessed radially outward. In the insulating member 5 covering the inner peripheral surface of the winding groove 4, the first portion 81 of the insulating paper, which is the first covering portion covering the first inner peripheral surface 41, extends to the circumferential front end Q1 of the first inner peripheral surface 41, whereas the outer peripheral side covering portion 95, which is the second covering portion overlapping the first covering portion, does not extend to the circumferential front end Q1 of the first inner peripheral surface 41. Therefore, since the opening width D of the winding slot 4 is increased radially outward by the thickness of the second insulating member 9, even when the split core 3 is rotated to wind the coil wire 60, the coil wire 60 can be provided to a space in which the first inner peripheral surface 41 is formed in a concave shape to be increased. This can ensure the radial thickness T of the split core outer peripheral portion 23 without increasing the outer shape of the split core 3, and can increase the number of turns of the coil wire 60 accommodated in the winding slot 4. Accordingly, the winding duty ratio increases, and the efficiency of the motor 1 increases.

In the present embodiment, the inner peripheral surface 950 of the outer peripheral side cover 95 (second cover) is disposed on the same plane as the virtual plane R that is orthogonal to the salient pole center line P extending in the radial direction through the center in the circumferential direction of the salient pole 22 and that passes through the circumferential front end of the inner peripheral surface of the insulating paper first portion 81. Therefore, it is possible to avoid a space in the winding slot 4 where the coil wire 60 cannot be provided, and thus the number of turns of the coil wire 60 can be increased.

Alternatively, the inner peripheral surface 950 of the outer peripheral side cover 95 (second cover) may be disposed radially inward of the virtual plane R. For example, if the depth of the recess of the first inner peripheral surface 41, which is a concave surface, is made smaller than the plate thickness of the outer peripheral side cover 95, the inner peripheral surface 950 of the outer peripheral side cover 95 is configured to protrude inward from the edge of the opening 40 of the winding slot 4. In such a configuration, a space in which the coil wire 60 cannot be provided can be avoided from being generated in the winding slot 4, and therefore, the number of turns of the coil wire 60 can be increased.

In the present embodiment, the thickness of the nomex paper constituting the first insulating member 8 is about 0.13 mm. The thickness of the outer circumferential side cover 95, the salient pole side cover 94, and the inner circumferential side cover 96 of the second insulating member 9 is 0.3mm or more. The coil wire 60 has a wire diameter of 0.2mm or more. In the structure of the present embodiment, at least the opening 40 of the winding groove 4 can be expanded radially outward by the plate thickness of the outer peripheral side cover 95. Therefore, if the wire diameter of the coil wire 60 is equal to or smaller than the plate thickness of the outer peripheral side cover 95, at least one row of coil wires 60 can be wound.

In the present embodiment, the first inner peripheral surface 41 of the winding slot 4 is a bent surface, and includes a first flat surface portion 44 extending from the salient pole 22 in a direction orthogonal to the salient pole center line P, and a second flat surface portion 45 bent with respect to the first flat surface portion 44 and extending to the circumferential tip Q1 of the first inner peripheral surface 41. In this way, when the concave surface has a curved surface, the manufacturing becomes easier than when the concave surface has a curved surface. Therefore, the split core 3 is easily manufactured, and the second insulating member 9 made of resin is easily manufactured.

The first inner peripheral surface 41 of the winding groove 4 may be a curved surface instead of a bent surface. For example, the first inner peripheral surface 41 may be an arc surface centered on the rotation axis L of the rotor 30. Thus, the radial thickness T of the split core outer peripheral portion 23 can be ensured without increasing the outer shape of the split core 3, and the winding slots 4 can be made wider.

In the present embodiment, the radial thickness T of the circumferential tip of the split core outer peripheral portion 23 is 50% or more of the circumferential thickness T0 of the salient pole 22, so that the necessary thickness of the split core outer peripheral portion 23 can be ensured.

In the present embodiment, as the first insulating member 8, an insulating paper such as nomex paper covering the entire range of the inner peripheral surface of the winding slot 4 in the direction of the rotation axis L is used. The first insulating member 8 is not limited to insulating paper, and may be a sheet-like insulating member (insulating sheet). The second insulating member 9 includes a first insulator 9A covering an end portion of one side (output side L1) of the split core 3 in the rotation axis direction and a second insulator 9B covering an end portion of the other side (opposite output side L2) of the split core 3 in the rotation axis direction. In this way, since the insulating paper is inserted into the winding slot 4 and then the insulators are attached from one side and the other side in the direction of the rotation axis L, the operation of assembling the split core 3 and the insulating member 5 is easy, and the gap of the insulators can be covered with the insulating paper, so that the split core 3 and the coil 6 can be reliably insulated.

Symbol description

1 … motor; 2 … output shaft; 3 … split cores; slots for 4 … windings; 5 … insulating parts; 6 … coil; 7 … wiring substrates; 8 … first insulating member; 8a … first insulating paper; 8B … second insulating paper; 9 … second insulating member; 9a … first insulator; 9B … second insulator; 10 … motor housing; 11 … cylindrical portions; 12 … first bearing seat; 13 … second bearing block; 14 … first bearing; 15 … second bearing; 16 … encoder housing; 20 … stator; 21 … stator core; 22 … salient poles; 23 … to divide the core outer circumference; 24 … to divide the core inner peripheral portion; 30 … rotor; 31 … rotation axis; 32 … rotor magnets; 40 … opening; 41 … first inner peripheral surface; 42 … second inner peripheral surface; 43 … third inner peripheral surface; 44 … first planar portion; 45 … second planar portion; 50 … split cores; 51 … salient poles; 53 … outer circumferential arc portion; 60 … coil wire; 71 … insulator; 73 … insulating paper; 81 … insulating paper first portion; 82 … insulation paper second portion; 83 … insulating paper third portion; 84 … first fold; 85 … second fold; 91 … salient pole end face cover; 92 … peripheral flange portions; 93 … inner peripheral flange portions; 94 … salient pole side covers; 95 … outer peripheral side cover portions; 96 … inner peripheral side cover portions; 97 … groove portions; 98 … recess; 950 … inner peripheral surface of the outer peripheral side cover; d … opening width; l … axis of rotation; l1 … output side; l2 … reverse output side; p … salient pole centerline; a circumferential front end of the Q0 … outer circumferential side cover; a circumferential front end of the first inner circumferential surface Q1 …; a circumferential front end of the inner peripheral surface of the Q2 … insulating paper first portion; r … imaginary plane; a concave surface of R1 …; s … winding slots.

Claims

1. A motor is provided with:

a stator including a stator core having a plurality of salient poles arranged radially, and a coil wound around the salient poles via an insulating member; and

a rotor disposed on an inner peripheral side of the stator,

it is characterized in that the method comprises the steps of,

the stator core includes a plurality of divided cores arranged in a circumferential direction,

the split core includes: a split core outer peripheral portion extending in a circumferential direction; the salient poles extending radially inward from a circumferential center of the split core outer circumferential portion; and a split core inner peripheral portion extending from a front end of the salient pole to both circumferential sides, winding slots surrounded by the split core outer peripheral portion, the salient pole, and the split core inner peripheral portion being provided on both circumferential sides of the salient pole,

the inner peripheral surface of the winding slot is provided with a first inner peripheral surface formed by the outer peripheral part of the split iron core, the first inner peripheral surface is a concave surface which is concave towards the radial outer side,

the insulating member is provided with: a first insulating member covering an inner peripheral surface of the winding groove; and a second insulating member overlapped with the first insulating member,

the first insulating member includes a first covering portion that covers the first inner peripheral surface,

the second insulating member has a second covering portion overlapping the first covering portion,

the circumferential front end of the second covering portion is located further to the salient pole side than the circumferential front end of the first inner circumferential surface.

2. The motor according to claim 1, wherein,

the inner peripheral surface of the second covering portion is disposed on the same surface as a virtual surface, which is orthogonal to a salient pole center line passing through a circumferential center of the salient pole and extending in a radial direction, and passes through a circumferential front end of the inner peripheral surface of the first covering portion, or is disposed radially inward of the virtual surface.

3. A motor according to claim 1 or 2, wherein,

the first inner peripheral surface is an arc surface centered on the rotational axis of the rotor.

4. A motor according to claim 1 or 2, wherein,

the first inner peripheral surface is a bent surface having a first planar portion extending from the salient pole in a direction orthogonal to a salient pole center line passing through a circumferential center of the salient pole and extending in a radial direction, and a second planar portion bent with respect to the first planar portion and extending to a circumferential front end of the first inner peripheral surface.

5. The motor according to any one of claims 1 to 4, wherein,

the radial thickness of the circumferential front end of the split core outer circumferential portion is 50% or more of the circumferential thickness of the salient pole.

6. The motor according to any one of claims 1 to 5, wherein,

the stator core extends in the direction of the rotational axis of the rotor,

the first insulating member is an insulating sheet covering the entire range of the inner peripheral surface of the winding groove in the rotation axis direction,

the second insulating member includes: a first insulator made of resin, the first insulator covering an end portion of the split core on one side in the rotation axis direction; and a second insulator made of resin, the second insulator covering an end portion of the split core on the other side in the rotation axis direction.