CN211930351U - Stator and brushless motor - Google Patents

Abstract

The utility model discloses a stator and brushless motor. The utility model discloses a topic lies in realizing miniaturizing in stator and the motor that is provided with package tooth and non-package tooth. A stator is provided with: a plurality of winding teeth (4B) that are arranged around the rotation center (C) at intervals and around which the winding (4D) is wound; a plurality of non-winding teeth (4C) that are disposed between two winding teeth (4B) adjacent to each other in the circumferential direction, which is the periphery of the rotation center (C), and around which the winding (4D) is not wound; and a connecting bus bar (4E) configured by laminating a plurality of bus bar members (5A, 5B, 5C, 5D), wherein the bus bar members (5A, 5B, 5C, 5D) are formed by fixing a conducting plate (20) for connecting the windings (4D) to the insulating member (10). In the stator, the connection bus bar (4E) is disposed on at least one of one end side and the other end side in the axial direction of the non-winding teeth (4C).

Description

Stator and brushless motor

Technical Field

The present invention relates to a stator in which a winding is connected by using a bus bar, and a brushless motor provided with the stator.

Background

Conventionally, a brushless motor has been put to practical use in which in-phase windings wound around teeth of a stator are connected to each other by using bus bars. For example, patent document 1 discloses a bus bar unit in which a plurality of metal bus bars are embedded in a resin molded body in an insulated state, and a winding is connected using the bus bar unit. By using the bus bar thus unitized, the assembling property of the motor can be improved.

However, in a stator of a brushless motor, there is known a structure in which teeth around which a winding is wound (hereinafter referred to as "wound teeth") and teeth around which a winding is not wound (hereinafter referred to as "non-wound teeth") are alternately arranged in a circumferential direction (see, for example, patent document 2). In such a brushless motor, the duty factor of the coil in each slot is increased, and therefore, the motor efficiency and the winding workability of the winding can be improved.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2010-233327

Patent document 2: japanese laid-open patent publication No. 2009-118611

SUMMERY OF THE UTILITY MODEL

Problem to be solved by utility model

However, in order to dispose the unitized bus bars as described above on the upper portion, the lower portion, and the outer peripheral portion of the stator core, a dedicated space needs to be secured in the motor case, which leads to an increase in the size of the motor. In particular, in the stator having the winding teeth wound with the winding and the non-winding teeth not wound with the winding as described above, the axial dimension increases by the winding at the position of the winding teeth, and therefore, in the configuration in which the bus bar is disposed on the upper portion or the lower portion of the winding, the axial dimension of the motor increases.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a stator and a motor provided with winding teeth and non-winding teeth, which are reduced in size. It is to be noted that the present invention is not limited to these objects, and another object of the present invention is to provide an operation and an effect by each configuration described later for implementing the embodiment of the present invention, that is, an operation and an effect which cannot be obtained by the conventional technique.

Means for solving the problems

(1) The stator disclosed herein includes: a plurality of winding teeth which are arranged around the rotation center at intervals and around which the winding is wound; a plurality of non-winding teeth that are disposed between two adjacent winding teeth in a circumferential direction that is a periphery of the rotation center, and around which the winding is not wound; and a wiring bus bar formed by laminating a plurality of bus bar members, wherein the bus bar members are formed by fixing a conductive plate for wiring the winding to an insulating member. The wire bus bar is disposed on at least one of one end side and the other end side in the axial direction of the non-wound tooth.

(2) Preferably, the busbar member includes an arm portion extending in a radial direction, the arm portion being provided along the non-winding tooth and having a connecting portion to which the winding is connected.

(3) Preferably, the insulating member has a groove recessed in a portion where the conduction plate is disposed.

(4) Preferably, the insulating member has a step portion formed in the arm portion in which the groove portion is formed, the step portion being formed by cutting a radial end portion of a side wall of the groove portion, and the conduction plate has a winding portion which is provided to extend to a position closer to a radial front end side than the step portion and is formed to be bent as the connection portion so as to wind the winding.

(5) Preferably, the wire connection bus bar is disposed on the one end side and the other end side of the non-winding tooth, respectively.

(6) Preferably, the winding teeth are fixed to a fixed core in a state in which the winding is wound, and the winding teeth connected to the connection bus bar disposed on the one end side of the non-winding teeth and the winding teeth connected to the connection bus bar disposed on the other end side of the non-winding teeth are fixed to the fixed core in a state in which the winding teeth are turned upside down in the axial direction with respect to the winding teeth.

(7) The brushless motor disclosed herein includes a rotor and the stator described in any one of (1) to (6) above.

Effect of the utility model

According to the disclosed stator and brushless motor, the dead space is used as the space for disposing the bus bar, and therefore, the dead space can be effectively utilized. This can reduce the thickness (axial dimension) and radial dimension required for disposing the wiring members (bus bars) in the related art, thereby achieving a reduction in size of the stator and the brushless motor. In addition, when the outer dimensions of the stator and the brushless motor are equal, the thickness and the radial dimension of the magnetic path (the core of the stator) can be increased, and therefore, the motor performance can be improved.

Drawings

Fig. 1 is a schematic side view showing a motor according to a first embodiment.

3 fig. 32 3 is 3a 3 sectional 3 view 3 taken 3 along 3 line 3a 3- 3a 3 of 3 fig. 3 1 3. 3

Fig. 3 is a perspective view showing the wiring bus bar provided in the stator of the motor of fig. 1 in an exploded manner.

Fig. 4 is an exploded perspective view of the wiring bus bar of fig. 3.

Fig. 5 is a perspective view showing one of a plurality of bus bar members constituting the wiring bus bar of fig. 3 disassembled into an insulating member and a conduction plate.

Fig. 6 is a perspective view showing a wiring bus bar in a stator according to a second embodiment in an exploded manner.

Fig. 7 is an exploded perspective view of one of the connection bus bars shown in fig. 6.

Fig. 8 is an exploded perspective view of the other connection busbar shown in fig. 6.

Fig. 9 is a schematic diagram for explaining a wiring method of the stator of fig. 6.

Fig. 10(a) to (c) are schematic views for explaining the mounting direction of the winding teeth incorporated in the stator of fig. 6. Wherein (a) is a connection method that can be used, and (b) and (c) are connection methods that cannot be used.

Description of reference numerals:

1 Motor (brushless motor)

2 rotor

4. 4' stator

4A fixed core

4B package tooth

4C non-package tooth

4D winding

4E, 4F, 4G wiring bus bar

5A first bus bar part (bus bar part)

5B second busbar part (busbar part)

5B' bus bar component

5C third busbar part (busbar part)

5D fourth busbar part (busbar part)

5D' busbar component

5E cover part

10 insulating member

11 groove part

11a side wall

12 step part

20 conducting plate

26 connecting part and winding part

52 arm part

Center of rotation of C

Detailed Description

A stator and a brushless motor according to an embodiment will be described with reference to the drawings. The embodiments described below are merely examples, and are not intended to exclude various modifications and technical applications that are not explicitly described in the embodiments below. The respective configurations of the present embodiment can be variously modified and implemented without departing from the gist thereof. Further, they may be selected as needed or may be appropriately combined.

[1. first embodiment ]

[1-1. Overall Structure ]

3 fig. 3 1 3 is 3a 3 schematic 3 side 3 view 3 of 3a 3 brushless 3 motor 3 1 3 ( 3 hereinafter 3 referred 3 to 3 as 3 " 3 motor 3 1 3" 3) 3 according 3 to 3 the 3 present 3 embodiment 3, 3 and 3 fig. 32 3 is 3a 3 sectional 3 view 3 taken 3 along 3 line 3a 3- 3a 3 of 3 fig. 3 1 3. 3 As shown in fig. 1 and 2, a motor 1 of the present embodiment is an outer rotor type brushless DC motor, and includes a rotor 2 that rotates integrally with a rotating shaft 3, and a stator 4 disposed inside the rotor 2.

As shown in fig. 1, the motor 1 of the present embodiment is provided with a base portion 1a at one end portion (lower portion in the figure) in the axial direction thereof for fixing the motor 1 to an object to be mounted (not shown). A holder 3A (hereinafter referred to as "bearing holder 3A") having a bearing (not shown) for axially supporting the rotary shaft 3 is erected at the center of the base portion 1 a. The bearing holder 3A has a cylindrical shape, and a bearing is fixed to an inner peripheral surface thereof and a stator 4 is fixed to an outer peripheral surface thereof. The center line of the bearing holder 3A coincides with the rotation center C of the rotating shaft 3, and the rotating shaft 3 is rotatably supported by the bearing holder 3A.

The rotor 2 includes a bottomed cylindrical rotor case 2A fixed to the upper portion of the rotating shaft 3, and a plurality of magnets 2B fixed to the inner circumferential side surface of the rotor case 2A. The rotor case 2A is open toward the base portion 1a, and has a through hole 2e in an upper surface portion 2d thereof, through which the rotary shaft 3 is inserted and fixed. The rotor case 2A is formed of a magnetic material (for example, an electromagnetic steel plate, pure iron, or a ferromagnetic and soft magnetic metal similar to pure iron), and functions as a yoke of the rotor 2. The upper surface portion 2d of the rotor case 2A of the present embodiment is formed in a stepped shape, but the shape of the rotor case 2A is not particularly limited. As shown in fig. 2, the plurality of magnets 2B are arranged at equal intervals in the circumferential direction of the rotor case 2A. In the present embodiment, a rotor 2 having a 12-pole magnet 2B is exemplified.

As shown in fig. 1 to 3, the stator 4 includes a stator core having a tooth provided with a winding 4D, and a connecting bar 4E for connecting the same-phase windings 4D to each other, the stator core includes a fixed core 4A (see fig. 3) fixed to the bearing holder 3A and two types of teeth 4B and 4C, and the winding 4D is wound around one of the teeth 4B. Fig. 3 is a perspective view showing the wiring bus bar 4E of the stator 4 in an exploded manner. In fig. 4, five members 5A to 5E constituting the connecting bus bar 4E are shown in an exploded manner.

As shown in fig. 3, the fixed core 4A is a cylindrical body located at the radial center of the stator 4, and a cylindrical space for fixing the bearing holder 3A is provided at the center thereof. The fixed core 4A is formed by stacking a plurality of steel plates in the axial direction, for example. A recess into which the teeth 4B and 4C are fitted and fixed is formed in the outer peripheral portion of the fixed core 4A of the present embodiment. That is, the stator 4 of the present embodiment has a split core structure in which the fixed core 4A is split into the teeth 4B and 4C.

A plurality of teeth 24B (hereinafter referred to as "package teeth 4B") around the rotation center C are arranged at intervals. An insulator (insulator) not shown is fitted to the winding teeth 4B, and any one of the U-phase, V-phase, and W-phase windings 4D is wound from above the insulator. The windings 4D of the respective phases are connected by a connection bus bar 4E, thereby forming U-phase, V-phase, and W-phase coils. In the stator 4 of the present embodiment, a Y-wiring system is adopted.

On the other hand, the teeth 4C of the unwound coil 4D (hereinafter referred to as "non-wound teeth 4C") function only as a magnetic path and are disposed between two wound teeth 4B adjacent to each other in the circumferential direction, which is the periphery of the rotation center C. That is, the winding teeth 4B and the non-winding teeth 4C are alternately arranged in parallel at intervals in the circumferential direction of the stator 4. Each of the teeth 4B and 4C is formed by stacking a plurality of steel plates in the axial direction, for example. The number of the winding teeth 4B is the same as the number of the non-winding teeth 4C.

Each of the teeth 4B and 4C has a tooth portion 41B and 41C extending in the radial direction and a blade portion 42B and 42C extending in the circumferential direction at the radially outer end portion of the tooth portion 41B and 41C, and is substantially T-shaped when viewed in the axial direction. A radially inner portion of each tooth portion 41B, 41C of each tooth 4B, 4C is provided with a convex portion that fits into a concave portion of the fixed core 4A. The winding teeth 4B are assembled to the fixed core 4A in a state in which the coil 4D is wound.

As shown in fig. 2, the stator 4 is disposed in the rotor case 2A so that the blade portions 42B and 42C of the teeth 4B and 4C face the magnet 2B with a gap therebetween. As shown in fig. 3, in the stator 4 of the present embodiment, the circumferential dimension of the blade portion 42B of the wound tooth 4B is smaller than the circumferential dimension of the blade portion 42C of the non-wound tooth 4C. In this way, by setting the circumferential dimensions of the two blade portions 42b and 42c to be different from each other, cogging torque can be suppressed.

[1-2. main part Structure ]

As shown in fig. 3 and 4, the connecting bus bar 4E of the present embodiment is configured by a plurality of (five) members 5A to 5E stacked in the axial direction, and is disposed on one axial end side of the fixed core 4A and the non-winding tooth 4C. In the following description, one end side (upper side in fig. 1, 3, and 4) of the wiring bus bar 4E disposed with respect to the fixed core 4A is referred to as "upper", and the opposite side is referred to as "lower". The connection bus bar 4E has a different structure by the uppermost member 5E and the other four members 5A to 5D.

As shown in fig. 4, each of the four components 5A to 5D is configured by combining an insulating member 10 serving as a base and a conductive plate 20 for connecting wires to the winding 4D. The insulating member 10 is formed of an insulating material (e.g., resin), and the conductive plate 20 is formed of a conductive material (e.g., copper) in a plate shape. Hereinafter, the respective members 5A to 5D are referred to as "bus bar members 5A to 5D", and when they are particularly distinguished, they are referred to as a first bus bar member 5A, a second bus bar member 5B, a third bus bar member 5C, and a fourth bus bar member 5D in this order from below. On the other hand, the part 5E is constituted only by the insulating member 10. Hereinafter, this member 5E is referred to as "cover member 5E". The cover member 5E has a function of insulating the uppermost surface of the wiring bus bar 4E, and is formed thinner than the thicknesses (axial dimensions) of the four bus bar members 5A to 5D.

Each of the bus bar members 5A to 5D and the cover member 5E has a hollow circular ring portion 51 having a disk shape and a plurality of arm portions 52 radially extending outward from the circular ring portion 51. As shown in fig. 2 and 3, the annular portion 51 is a portion located on the fixed core 4A, and has a circular hole portion through which the bearing holder 3A penetrates at the radial center thereof. The arm portions 52 are provided in the same number as the winding teeth 4B (nine in the present embodiment), and extend in the radial direction so as to extend along the respective tooth portions 41C of the non-winding teeth 4C. In other words, the connecting bus bar 4E is disposed at a position where the winding teeth 4B and the windings 4D wound around the winding teeth 4B are not present.

As shown in fig. 4, the insulating member 10 is provided in each of the members 5A to 5E, and includes the annular portion 51 and the arm portion 52. The four bus bar members 5A to 5D are all formed to have the same thickness. The annular portions 51 of the insulating members 10 of the five members 5A to 5E are all formed in the same shape, and as shown in fig. 3, the inner circumferential surface positions and the outer circumferential surface positions are matched in the state of being overlapped in the axial direction. On the other hand, the arm portions 52 of the five members 5A to 5E are different in length (radial dimension).

As shown in fig. 4, the conduction plate 20 is provided on each of the bus bar members 5A to 5D, and forms a circuit between two or three or more windings 4D. Conduction plate 20 includes three types of structures, namely, a structure that functions as an input line for supplying electric power to windings 4D of the respective phases (hereinafter referred to as "input unit 23"), a structure that functions as a jumper line for connecting windings 4D of the same phase (hereinafter referred to as "jumper unit 24"), and a structure that functions as a neutral point (hereinafter referred to as "neutral point unit 25"). In the connecting bus bar 4E of the present embodiment, three input portions 23 are provided to the fourth bus bar member 5D, and one neutral point portion 25 is provided to the second bus bar member 5B. The jumper section 24 is provided in all of the bus bar members 5A to 5D.

Here, fig. 5 shows a perspective view in which the second bus bar member 5B is disassembled into the insulating member 10 and the conduction plate 20 (the crossover portion 24 and the neutral point portion 25). The other bus bar members 5A, 5C, and 5D are also configured substantially similarly to the second bus bar member 5B. As shown in fig. 4 and 5, the insulating member 10 of the bus bar members 5A to 5D has a groove 11 recessed in a portion where the conduction plate 20 is disposed. The groove 11 is formed in a shape to accommodate various conduction plates 20, and the depth of the groove 11 is set to be equal to or greater than the thickness of the conduction plate 20. In the present embodiment, the depth of the groove 11 is formed to be larger than the thickness of the conductive plate 20, and the conductive plate 20 does not protrude from the surface of the insulating member 10 in a state of being placed in the groove 11.

In the bus bar members 5A to 5D of the present embodiment, the rear surface (surface opposite to the surface on which the conduction plate 20 is disposed, and not shown) of the insulating member 10 is formed in a flat shape. The wiring bus bar 4E also ensures insulation on the upper surface side of the conduction plate 20 by stacking the members 5A to 5E in the axial direction. When the depth of the groove 11 is smaller than the thickness of the conductive plate 20, a groove having a shape for accommodating the conductive plate 20 may be formed also in the rear surface of the insulating member 10, and the conductive plate 20 may be accommodated in the groove, thereby securing insulation.

As shown in fig. 5, the crossover portion 24 and the neutral point portion 25 are provided with an arc portion 21 having an arc shape as viewed in the axial direction, a straight portion 22 having a straight line shape, and a connecting portion 26 formed by bending at a radially outer end portion of the straight portion 22. As shown in fig. 4, the input section 23 is provided with a linear section 22 and a connection section 26. The circular arc portion 21 is a part of the circular ring portion 51, and the linear portion 22 and the connecting portion 26 are a part of the arm portion 52. The connection portion 26 is a portion to which the winding 4D is connected, and is provided as a winding portion around which the winding 4D is wound, for example. In the conduction plate 20 of the present embodiment, the winding portion as the connection portion 26 is bent at 90 degrees with respect to the straight portion 22, and is formed to have a length protruding upward from the surface of the insulating member 10, and the distal end portion thereof has a wide shape. Hereinafter, the winding portion 26 is also referred to.

As shown in fig. 4 and 5, in the connecting bus bar 4E of the present embodiment, the arm portion 52 of the insulating member 10 in which the groove portion 11 is formed is provided with the stepped portion 12 formed by cutting out the radial end portion of the side wall 11a of the groove portion 11. The step portion 12 is a portion that secures a space for easily winding the winding 4D around the winding portion 26. The step portion 12 is provided to be coplanar with the bottom surface 11b of the groove portion 11. The winding portion 26 of the conduction plate 20 is formed by extending to a position on the radial front end side of the stepped portion 12 and bending in the axial direction, thereby suppressing an increase in the axial dimension of the connection bus bar 4E and securing a track for winding the winding 4D.

The length of the arm portion 52 is set from the viewpoint of ease of winding the coil 4D and ensuring insulation. Specifically, as shown in fig. 2 to 4, the arm portions 52 of the first bus bar member 5A located at the lowermost portion have the same length, and are set to be slightly shorter than the axial dimension of the tooth portion 41C of the non-winding tooth 4C. In the second bus bar member 5B, the arm portion 52 overlapped on the conduction plate 20 of the first bus bar member 5A is extended to the step portion 12 of the first bus bar member 5A, and the arm portion 52 not overlapped with the conduction plate 20 is set to the same length as that of the arm portion 52 of the first bus bar member 5A. In other words, two kinds of long and short arm portions 52 are provided in the second bus bar member 5B.

The arm portions 52 of the third bus bar member 5C are all the same in length, and are set to be the same in length as the shorter arm portions 52 of the second bus bar member 5B. In the fourth bus bar member 5D, the arm portion 52 overlapped on the conduction plate 20 of the third bus bar member 5C is extended to the step portion 12 of the third bus bar member 5C, and the arm portion 52 not overlapped with the conduction plate 20 is set to the same length as that of the arm portion 52 of the third bus bar member 5C. In other words, two kinds of long and short arm portions 52 are provided in the fourth bus bar member 5D. The arm portions 52 of the cover member 5E are all the same length, and are set to be the same length as the shorter arm portions 52 of the fourth bus bar member 5D. Note that, although the step portion 12 is not provided in the fourth bus bar member 5D of the present embodiment, the step portion 12 may be provided similarly to the other bus bar members 5A to 5C.

The insulating member 10 of the present embodiment is provided with an engaging portion 13 for coupling the upper and lower components 5A to 5E, and a positioning portion 14 for positioning the conduction plate 20 fixed to the insulating member 10. The engaging portion 13 includes a convex protrusion, and a recess or hole (not shown) into which the protrusion is fitted. The positioning portion 14 is provided as a protrusion that engages with a positioning hole 27 provided in the conduction plate 20. The configurations of the engaging portion 13, the positioning portion 14, and the positioning hole 27 are not particularly limited.

[1-3. Effect ]

(1) In the stator 4 described above, the wire connection bus bar 4E for connecting the winding 4D is disposed on one end side in the axial direction of the non-wound tooth 4C. Since the axial dimension of the non-winding tooth 4C is reduced by the amount corresponding to the winding 4D as compared with the axial dimension at the position of the winding tooth 4B, the space on both sides in the axial direction of the non-winding tooth 4C has conventionally become an ineffective space.

In contrast, according to the stator 4 described above, the dead space is used as the space for disposing the bus bar 4E, and therefore, the dead space can be effectively used. This can reduce the thickness (axial dimension) and radial dimension that have been conventionally required for arranging the wiring members (bus bars), and thus can reduce the size of the stator 4 and the motor 1. In addition, when the outer dimensions of the stator 4 and the motor 1 are equal, the thickness and the radial dimension of the magnetic path (the fixed core 4A) can be increased, and therefore, the motor performance can be improved.

(2) In the stator 4 described above, the arm portion 52 provided in the bus bar members 5A to 5D extends in the radial direction along the non-winding teeth 4C, and the arm portion 52 has the connecting portion 26 to which the winding 4D is connected, so that the stator 4 and the motor 1 can be downsized.

(3) According to the stator 4 described above, since the conduction plate 20 is disposed in the groove 11 of the insulating member 10, an increase in the axial dimension of the connecting bus bar 4E can be suppressed. In addition, the position of the conduction plate 20 with respect to the insulating member 10 can be accurately aligned, and the positional displacement of the conduction plate 20 can be prevented.

(4) In the insulating member 10, the step portion 12 is provided at the tip end portion of the arm portion 52 in which the groove portion 11 is formed, and the winding portion 26 (connecting portion) of the conductive plate 20 is formed by extending and bending to the tip end side in the radial direction from the step portion 12. This can suppress the axial dimension of the bus bar 4E and ensure a track for winding the coil 4D around the winding portion 26. That is, the stator 4 and the motor 1 can be downsized, and the winding workability of the winding 4D can be improved.

(5) In the insulating member 10 of the present embodiment, the depth of the groove 11 is set to be equal to or greater than the thickness of the conductive plate 20, and therefore the conductive plate 20 can be set in a state not protruding from the surface of the insulating member 10. This allows the members 5A to 5E to be stacked in a state in which the insulation properties of the plurality of bus bar members 5A to 5D are reliably ensured.

[2. second embodiment ]

[2-1. Structure ]

Next, a motor and a stator 4' according to a second embodiment will be described with reference to fig. 6 to 10 (c). The motor and the stator 4' of the present embodiment are configured in the same manner as the motor 1 and the stator 4 of the first embodiment, except that the structure and the arrangement of the wire connecting bus bars 4F and 4G and the method of assembling the winding teeth 4B are different. Hereinafter, the same components as those of the first embodiment are denoted by the same reference numerals, and components obtained by partially modifying the components of the first embodiment are denoted by the same reference numerals as those of the first embodiment (with prime notation), and redundant description thereof will be omitted. Fig. 6 corresponds to fig. 3 described above, and fig. 7 and 8 correspond to fig. 4 described above.

As shown in fig. 6, the stator 4' of the present embodiment has two wiring bus bars 4F, 4G. One connection bus bar 4F (hereinafter also referred to as "upper connection bus bar 4F") is disposed on one axial end side (upper side in the drawing) of the fixed core 4A and the non-wound tooth 4C. The other wire connection bus bar 4G (hereinafter also referred to as "lower wire connection bus bar 4G") is disposed on the other axial end side (lower side in the drawing) of the fixed core 4A and the non-winding tooth 4C. Each of the bus bars 4F and 4G is configured by stacking a plurality of (three in this case) members in the axial direction, similarly to the bus bar 4E described above.

As shown in fig. 7, the upper connection bus bar 4F is formed by two bus bar members 5A and 5B' and the lid member 5E described above being axially overlapped. The lowermost bus bar member 5A directly placed on the fixed core 4A and the non-winding teeth 4C is the same as the first bus bar member 5A of the first embodiment. The other bus bar member 5B' is also configured substantially similarly to the second bus bar member 5B of the first embodiment. That is, the upper-side bus bar 4F is provided with a crossover portion 24 and a neutral point portion 25.

As shown in fig. 8, the lower connecting bus bar 4G is formed by two bus bar members 5A and 5D' and the lid member 5E described above being axially overlapped. The uppermost bus bar member 5A directly mounted on the fixed core 4A and the non-winding tooth 4C is the same as the first bus bar member 5A of the first embodiment. The other bus bar member 5D' is also configured substantially similarly to the fourth bus bar member 5D of the first embodiment. That is, the lower-side bus bar 4G is provided with an input portion 23 and a crossover portion 24. The lower connecting bus bar 4G is disposed in such an orientation that the first bus bar member 5A is located on the core side (upper side in fig. 6) and the lid member 5E is located on the opposite side (lower side in fig. 6) from the core.

In the stator 4' of the present embodiment, the two connection bus bars 4F and 4G are arranged so as to sandwich the fixed core 4A and the non-wound tooth 4C from both axial sides. Here, a wiring method for connecting the coils 4D of the same phase wound around the winding teeth 4B according to the present embodiment will be described with reference to fig. 9. In fig. 9, the teeth 4B and 4C arranged in parallel in the circumferential direction are indicated by rectangles denoted by letters (U, V, W). The "one end side" and "the" other end side "in fig. 9 correspond to the one axial end side (upper side in the drawing) and the other axial end side (lower side in the drawing) shown in fig. 6 to 8.

As shown in fig. 9, in nine winding teeth 4B arranged at intervals, windings 4D are wound in one direction (clockwise direction in this case), and the windings 4D of the same phase are connected to each other by a crossover portion 24 (conduction plate 20). For example, focusing on the U-phase, the winding start point of the winding 4D of the winding tooth 4B located at the left end in the figure is connected to the input unit 23, and the winding tooth 4B is wound with a predetermined number of turns. The winding end point of the winding 4D is connected to one end (connection portion 26) of the jumper portion 24 of the bus bar member 5A provided in the connection bus bar 4F.

The other end portion (the further connecting portion 26) of the jumper portion 24 is connected to the winding start point of the winding 4D wound around the winding tooth 4B of the second U-phase. The winding 4D is wound around the winding tooth 4B with a predetermined number of turns, and the winding end thereof is connected to one end (connection portion 26) of the crossover portion 24 of the bus bar member 5A provided in the wire connection bus bar 4G. The other end portion (the further connecting portion 26) of the jumper portion 24 is connected to a winding start point of the winding 4D wound around the winding tooth 4B of the third U-phase. The winding 4D is wound around the winding teeth 4B with a predetermined number of turns, and the winding end thereof is connected to a neutral point portion 25 of a bus bar member 5B' provided in the bus bar 4F.

Here, in the stator 4' of the present embodiment, the second winding tooth 4B (indicated by a dot in fig. 9) in which the winding start point of the winding 4D is connected to the terminal bus bar 4F disposed on one end side, and the first and third winding teeth 4B in which the winding start point of the winding 4D is connected to the terminal bus bar 4G disposed on the other end side are fixed to the fixed core 4A in a state of being turned upside down in the axial direction. The mounting direction of the winding tooth 4B will be described with reference to (a) to (c) of fig. 10. Fig. 10(a) is a partial section of fig. 9, and fig. 10 (b) and (c) are comparative examples.

As described above, since the winding 4D is wound around each winding tooth 4B in the same direction, if the directions of all the winding teeth 4B are the same as shown in fig. 10 (B), the winding start point S of the winding 4D is located upward in the figure, and the winding end point E of the winding 4D is located downward in the figure. Therefore, in order to connect the winding end point E to the next winding start point S, the teeth 4B, 4C need to be cut along the upper and lower longitudinal lines as indicated by the two-dot chain line in the figure. However, since the wiring bus bars 4F and 4G are arranged vertically, this connection method cannot be adopted. In addition, as shown in fig. 10 (c), in the configuration in which the lower side of the winding 4D wound around the second winding tooth 4B is set as the winding start point S and is connected to the winding end point E of the winding 4D wound around the first winding tooth 4B, the winding direction of the winding 4D is reversed, and therefore this connection method cannot be adopted.

In contrast to these methods, in the stator 4' of the present embodiment, as shown in fig. 10(a), the second winding teeth 4B are turned upside down. Thus, the winding start point S is located below and the winding end point E is located above, and therefore the winding start point S and the winding end point E are connected by the lower crossover portion 24 without reversing the winding direction of the winding 4D.

[2-2. Effect ]

(1) According to the stator 4' of the present embodiment, since the connection bus bars 4F and 4G are arranged on one end side and the other end side of the non-wound tooth 4C, both the spaces invalidated on both the axial sides of the non-wound tooth 4C can be used. The thickness (axial dimension) of each of the bus bars 4F and 4G can be made smaller than the bus bar 4E of the first embodiment. This enables the stator 4 'and the motor including the stator 4' to be further reduced in size. In addition, when the outer dimensions of the stator 4' and the motor are equal, the thickness and the radial dimension of the magnetic path (the fixed core 4A) can be increased, and therefore, the motor performance can be improved.

Further, when there are members having the same shape among the plurality of members constituting the two wiring bus bars 4F and 4G, the members can be shared, and therefore, the cost can be reduced. In the connection bus bars 4F and 4G of the present embodiment, the bus bar member 5A and the lid member 5E are common to each other, and therefore, four kinds of members (the bus bar members 5A, 5B ', 5D' and the lid member 5E) may be prepared in total.

By disposing the bus bar connectors 4F and 4G on both sides in the axial direction, as shown in fig. 6, the connection portions 26 can be disposed in the circumferential direction of the bus bar connectors 4F and 4G one by one. Thus, for example, compared to the connection bus bar 4E in which a plurality of connection portions 26 are arranged at one circumferential position as in the first embodiment, the component configuration can be simplified, and the winding workability of the winding 4D can be improved.

(2) In the stator 4', the winding teeth 4B to which the winding start point of the winding 4D and the bus bar 4F on one end side are connected are attached so as to be vertically reversed, and therefore the winding 4D can be connected to the winding teeth 4B via the bus bar 4F without reversing the winding direction of the winding 4D wound around the winding teeth 4B. In other words, the winding direction of the coil 4D can be unified into one direction, and thus productivity can be improved. The same effects can be obtained by the same configurations as those of the above-described embodiment.

[3. other ]

The configurations of the stators 4 and 4' and the motor 1 are examples, and are not limited to the above configurations. For example, the length of the arm portion 52 of the wire connecting bus bars 4E, 4F, 4G and the depth of the groove portion 11 may be changed from the above-described configurations, and the groove portion 11 and the step portion 12 may be omitted. Further, a method of fixing the conduction plate 20 to the insulating member 10 and a method of combining the bus bar members are not particularly limited. In the first embodiment, the order of stacking the four bus bar members 5A to 5D may be different from the above-described order. Similarly, in the second embodiment, the stacking order is not particularly limited. Further, the insulating properties of the wiring bus bars 4E, 4F, 4G may be ensured by a member other than the above-described cover member 5E.

In the first embodiment described above, the wire connection bus bar 4E is disposed on one axial end side (upper side in fig. 1 and 3) of the fixed core 4A and the non-wound tooth 4C, but the wire connection bus bar 4E may be disposed on the other axial end side (lower side in fig. 1 and 3). If the wire connecting bus bar is disposed on at least one of the one end side and the other end side in the axial direction of the non-wound tooth 4C, the space that has been conventionally invalidated can be effectively utilized, and the motor size (stator size) can be reduced.

In the second embodiment described above, the winding teeth 4B indicated by dots in fig. 9 are attached to the fixed core 4A by being turned up and down, but any one of the winding teeth may be attached to the fixed core without being turned up and down by providing the winding teeth wound around the winding 4D clockwise and the winding teeth wound around the winding 4D counterclockwise. In the above-described embodiment, the wound portion is exemplified as the connection portion 26 for connecting the winding 4D, but the method for connecting the winding 4D and the wiring bus bar 4E is not particularly limited, and the shape of the connection portion 26 is not limited to the above-described configuration.

In the above embodiments, the stators 4 and 4' that are split core structures in which both the teeth 4B and 4C are attached to the fixed core 4A are exemplified, but the stators may not be split core structures. For example, the stator may be configured such that the fixed core is integrated with the non-winding teeth and only the winding teeth are assembled later, or the winding teeth may be integrated with the stator.

In the above embodiments, the stators 4 and 4' each provided with nine winding teeth 4B and non-winding teeth 4C are exemplified, but the number of teeth is not particularly limited. Similarly, the number of poles of the magnet 2B of the rotor 2 is not particularly limited. The number and shape of the bus bar members constituting the wire connecting bus bar, and the shape and arrangement of the crossover portion may be appropriately set according to the number of teeth and the number of poles of the magnet. In the above-described embodiment, the Y-connection type stators 4 and 4' are exemplified, but the connection type is not limited thereto, and may be, for example, a Δ connection. The motor 1 is an outer rotor type, but the same structure as the stators 4 and 4' described above can be applied to an inner rotor type brushless motor.

Claims (8)

1. A stator is characterized by comprising:

a plurality of winding teeth which are arranged around the rotation center at intervals and around which the winding is wound;

a plurality of non-winding teeth that are disposed between two adjacent winding teeth in a circumferential direction that is a periphery of the rotation center, and around which the winding is not wound; and

a wiring bus bar formed by laminating a plurality of bus bar members, each bus bar member being formed by fixing a conductive plate for wiring the winding to an insulating member,

the wire bus bar is disposed on at least one of one end side and the other end side in the axial direction of the non-wound tooth.

2. The stator according to claim 1,

the busbar part is provided with an arm part extending in the radial direction,

the arm portion is provided along the non-winding tooth and has a connecting portion to which the winding is connected.

3. The stator according to claim 1,

the insulating member has a groove recessed in a portion where the conduction plate is disposed.

4. The stator according to claim 2,

the insulating member has a groove recessed in a portion where the conduction plate is disposed.

5. The stator according to claim 4,

the insulating member has a stepped portion formed at the arm portion where the groove portion is formed, and the stepped portion is formed by cutting off a radial end portion of a side wall of the groove portion,

the conductive plate has a winding portion that extends to a position on a radial tip side of the stepped portion and is formed to be bent to form the connection portion around which the coil is wound.

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

the wire bus bar is disposed on the one end side and the other end side of the non-winding tooth.

7. The stator according to claim 6,

the winding teeth are fixed to a fixed core in a state in which the winding is wound,

the winding teeth, to which the winding start point of the winding is connected to the connection bus bar disposed on the one end side of the non-winding teeth, are fixed to the fixed core in a state of being turned upside down in the axial direction with respect to the winding teeth, to which the winding start point of the winding is connected to the connection bus bar disposed on the other end side of the non-winding teeth.

8. A brushless motor is characterized by comprising:

a rotor; and

a stator according to any one of claims 1 to 7.

Images