CN111953114A

CN111953114A - Stator, motor, and air blower

Info

Publication number: CN111953114A
Application number: CN202010395637.0A
Authority: CN
Inventors: 笹栗启嗣
Original assignee: Nidec Corp
Current assignee: Nidec Corp
Priority date: 2019-05-17
Filing date: 2020-05-12
Publication date: 2020-11-17
Anticipated expiration: 2040-05-12
Also published as: CN111953114B; JP7255348B2; JP2020188645A

Abstract

Provided are a stator, a motor, and an air blower, wherein the stator has a stator core and a coil section, the stator core has an annular core back and a plurality of tooth sections extending in a radial direction from the core back, and each tooth section has: an inner tooth portion extending in a radial direction from a radially outer surface of the core back portion; a connecting portion connected to a radially outer end of the inner tooth portion and extending in a circumferential direction; and 3 or more outer tooth portions extending radially outward from the radially outer surface of the coupling portion and arranged in the circumferential direction, the coil portion including: an inner coil portion formed by winding a conductive wire around the inner tooth portion; and a plurality of outer coil portions formed by winding a conductive wire around the outer teeth, the inner coil portion and the plurality of outer coil portions of each tooth being formed of 1 conductive wire.

Description

Stator, motor, and air blower

Technical Field

The invention relates to a stator, a motor and an air supply device.

Background

A stator of a rotary machine is disclosed in japanese patent laid-open No. 2001-169495. The stator has a plurality of magnetic poles formed by winding a stator coil around a plurality of pole teeth radially protruding from a stator core with a bobbin of insulating resin interposed therebetween.

Patent document 1: japanese patent laid-open No. 2001-169495

In general, in a motor, the number of turns of a stator coil can be increased to increase output torque. In the case of the rotary machine described in japanese patent application laid-open No. 2001-169495, when the number of windings of the stator coil is increased, interference with the adjacent stator coil may occur. Therefore, when the number of windings is increased, the outer diameter of the motor is increased, and it is difficult to reduce the size.

Disclosure of Invention

Therefore, an object of the present invention is to provide a stator in which the number of windings can be increased without increasing the size of the stator.

Another object of the present invention is to provide a motor capable of increasing output torque without increasing the size of the motor.

Further, an object of the present invention is to provide a blower device capable of increasing the air volume without increasing the size.

An exemplary stator of the present invention includes: a stator core; and a coil portion formed by winding a conductive wire around a portion of the stator core, wherein the stator core has: an annular iron core back; and a plurality of teeth portions extending in a radial direction from the core back portion and arranged in a circumferential direction, each of the teeth portions having: an inner tooth portion extending radially from a radially outer surface of the core back portion; a connection portion connected to a radially outer end of the inner tooth portion and extending in a circumferential direction; and 3 or more outer tooth portions extending radially outward from a radially outer surface of the coupling portion and arranged in a circumferential direction, the coil portion including: an inner coil portion formed by winding a conductive wire around the inner tooth portion; and a plurality of outer coil portions formed by winding a conductive wire around the outer teeth portions, the inner coil portions and the plurality of outer coil portions being formed of 1 conductive wire.

According to the exemplary stator of the present invention, the number of windings can be increased without increasing the size.

Further, according to the exemplary motor of the present invention, the output torque can be increased without increasing the size.

According to the exemplary air blowing device of the present invention, air can be blown with a stable air volume.

Drawings

Fig. 1 is a perspective view showing an example of the air blowing device of the present invention.

Fig. 2 is a longitudinal sectional view showing the air blowing device shown in fig. 1.

Fig. 3 is a cross-sectional view taken along a plane perpendicular to the central axis of the motor.

Fig. 4 is a plan view of the stator with the coil part removed.

Fig. 5 is a perspective view of the stator core.

Fig. 6 is a schematic view of the teeth portion showing the winding sequence of the wire.

Fig. 7 is a diagram illustrating flows of magnetic forces generated when current flows through the inner coil portion and the outer coil portion of the tooth portion.

Fig. 8 is a plan view showing a modification of the stator core.

Description of the reference symbols

1: a rotor; 11: a rotor core; 12: a rotor housing; 13: a rotor magnet; 14: a shielding member; 2: a stator; 3: a stator core; 30: a stator piece; 31: the back of the iron core; 311: a through hole; 312: dividing the back of the iron core; 32: a tooth portion; 321: an inner tooth portion; 322: a connecting portion; 323: 1 st outer tooth part; 324: 2 nd external tooth part; 325: a 3 rd outer tooth portion; 326: an umbrella part; 33: dividing the iron core; 3 a: a stator core; 31 a: the back of the iron core; 4: an insulating member; 40: a cover portion; 41: a protrusion; 42: a wall portion; 5: a coil section; 50 a: 1, lapping wires; 50 b: 2, lapping wires; 50 c: 3, lapping wires; 50 d: step 4, lapping wires; 51: an inner coil portion; 52: 1 st outer coil part; 53: a 2 nd outer coil section; 54: a 3 rd outer coil part; 6: a bearing; 61: an outer ring; 62: an inner ring; 7: a wiring substrate; 100: a pillar; 101: a base part; 110: a rotor sheet; 200: a motor; 300: an impeller; 301: an impeller housing; 302: a blade; 303: a bearing mounting portion; 304: a cover portion; 305: a main body portion; 306: a through hole; 307: a rotor mounting portion; 308: a rotor mounting cover; 309: a rotor mounting cylinder; 3221: an inclined portion; a: an air supply device; cx: a central axis.

Detailed Description

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the present specification, a direction parallel to the central axis Cx of the air blowing device a is referred to as an "axial direction". The direction perpendicular to the central axis Cx is referred to as a "radial direction". The direction along the arc centered on the central axis Cx is referred to as the "circumferential direction". The names of the above-described direction and surface are used for the sake of explanation, and are not limited to the positional relationship and direction in the use state of the air blowing device a and the motor 200.

< 1. air supply device A >

Fig. 1 is a perspective view showing an example of an air blowing device a of the present invention. Fig. 2 is a longitudinal sectional view of the blower a shown in fig. 1. As shown in fig. 1 and 2, the air blower a of the present embodiment is a sealed fan.

The blower a includes a support 100, a motor 200, and an impeller 300. The impeller 300 is attached to the column 100 via a bearing 6 and rotated by driving of the motor 200. By the rotation of the impeller 300, an airflow toward the axially lower side is generated.

< 2 > pillar 100

The support column 100 is disposed along a central axis Cx extending vertically. The column 100 is a cylindrical member made of metal, for example. A lead (not shown) connected to a circuit board 7 (described later) included in the motor 200 is disposed inside the support column 100. The support column 100 may be made of a material other than metal such as ceramic.

The column 100 is fixed to a ceiling (not shown) of a room. A base portion 101 is provided at an axially lower end portion of the strut 100. The base portion 101 expands in the radial direction. The base portion 101 may be formed integrally with the column 100, or may be attached to the column 100.

< 3. impeller 300 >

As shown in fig. 1 and 2, the impeller 300 has an impeller housing 301 and a plurality of blades 302. The impeller 300 generates an air flow from the axial direction to the downward direction. The impeller housing 301 is rotatably supported by the column 100 via a bearing 6. The impeller housing 301 has a space therein, and a part of the strut 100 and the motor 200 are disposed inside the impeller housing 301.

The plurality of blades 302 are disposed on the upper surface of the impeller housing 301. The plurality of blades 302 are arranged in the circumferential direction. In the air blower a of the present embodiment, the blades 302 are arranged at equal intervals on the upper surface of the impeller housing 301. In impeller 300 of the present embodiment, there are 3 blades 302, but the number is not limited to this, and may be 4 or more, or 2 or less.

The impeller housing 301 has a bearing mounting portion 303 at an axially upper end portion. The bearing mounting portion 303 is rotatably mounted to the column 100 by 2 bearings 6 arranged to be spaced apart in the axial direction. The bearing mounting portion 303 has a cover cylindrical shape. The bearing mounting portion 303 includes a lid portion 304 and a body portion 305. The cover portion 304 is provided at an axially upper end of the bearing mounting portion 303 and spreads radially inward. The body 305 has a cylindrical shape extending axially downward from the radially outer edge of the cover 304.

The cover 304 has a through hole 306 penetrating in the axial direction at a radially central portion. The support 100 passes through the through hole 306. A bearing 6 is disposed inside the bearing mounting portion 303. In the present embodiment, the bearing 6 is a ball bearing. The strut 100 is fixed to the inner race 62 of the bearing 6. The outer race 61 of the bearing 6 is fixed to the inner surface of the body 305. Thereby, the impeller housing 301 is rotatably supported by the column 100 via the bearing 6.

The impeller casing 301 has a rotor mounting portion 307 in the form of a cover cylinder therein. The rotor mounting portion 307 is integrally manufactured with the impeller housing 301. The rotor mounting portion 307 has a rotor mounting cover portion 308 and a rotor mounting cylindrical portion 309. The rotor attachment cover portion 308 is a disk-shaped portion that extends in a direction perpendicular to the center axis Cx at an axially upper end portion inside the impeller casing 301. The rotor mounting cylinder 309 extends axially downward from a radially outer edge of the rotor mounting cover 308. The rotor 1 is fixed to the rotor mounting portion 307. More specifically, a rotor case 12, which will be described later, having a rotor core 11 and a rotor magnet 13, which will be described later, therein is fixed to the rotor mounting portion 307.

< 4. Motor 200 >

Next, the structure of the motor 200 will be described. Fig. 3 is a cross-sectional view taken along a plane perpendicular to the central axis Cx of the motor 200. As shown in fig. 2 and 3, the motor 200 includes a rotor 1 and a stator 2. Hereinafter, each part of the rotor 1 and the stator 2 will be described in detail. The stator 2 of the motor 200 is radially opposed to the inner circumferential surface of the rotor 1. That is, the motor 200 is an outer rotor type DC brushless motor.

< 4.1 rotor 1 >

As shown in fig. 2 and 3, the rotor 1 includes a rotor core 11, a rotor case 12, and a rotor magnet 13. The rotor magnets 13 are arranged such that the S poles or the N poles alternate in the circumferential direction.

The rotor core 11 annularly surrounds the central axis Cx and is formed by axially laminating a plurality of rotor sheets 110 made of electromagnetic steel plates or the like. Rotor core 11 is fixed by a fixing method such as caulking while rotor pieces 110 are axially overlapped. Thereby, the rotor core 11 has a ring shape extending along the central axis Cx. The fixation of the rotor piece 110 is not limited to caulking, and a fixation method such as bonding or welding may be employed. The rotor core 11 is not limited to the laminated body, and may be a molded body formed by fixing magnetic powder such as iron powder by sintering or the like.

The rotor core 11 has a ring shape centered on the central axis Cx. A rotor magnet 13 is disposed on the rotor core 11. The rotor case 12 is a holding member that holds the rotor core 11 therein. The rotor case 12 is cylindrical and contacts a part of the radially outer side of the rotor core 11 in the axial direction. Thereby, the rotor case 12 holds the rotor core 11. The method of fixing the rotor case 12 and the rotor core 11 is not limited to press fitting, for example. For example, a method of fixing the rotor case 12 and the rotor core 11 by bonding, welding, or the like is widely used.

< 4.2 stator 2 >

Next, the stator 2 will be described with reference to the drawings. Fig. 4 is a plan view of the stator 2 with the coil part 5 removed. Fig. 5 is a perspective view of the stator core 3. Fig. 6 is a schematic view of the teeth portion showing the winding sequence of the wire.

As shown in fig. 3, the stator 2 is radially opposed to the rotor 1. The stator 2 is an armature that generates magnetic force according to a driving current. As shown in fig. 2 to 4, etc., the stator 2 has a stator core 3, an insulator 4, and a coil portion 5. The stator 2 includes a stator core 3 and a coil portion 5, and the coil portion 5 is formed by winding a conductive wire around a part of the stator core 3. The motor 200 is, for example, a three-phase DC brushless motor. Therefore, three-phase currents having different phases of U-phase, V-phase, and W-phase are supplied to the coil portion 5 of the motor 200.

< 4.3 stator core 3 >

As shown in fig. 5, the stator core 3 is formed by axially laminating a plurality of stator pieces 30 made of electromagnetic steel plates or the like. For ease of explanation, in the stator piece 30 shown in fig. 5, the axial thickness is shown to be thicker than the actual stator piece 30 with respect to the dimensions of the core back 31 and the tooth 32, which will be described later.

The stator core 3 is fixed by axially overlapping the stator pieces 30 and fixing them by a fixing method such as caulking. The fixing of the stator piece 30 is not limited to caulking, and may be performed by a fixing method such as bonding or welding. The stator core 3 is not limited to the laminated body, and may be a molded body formed by fixing magnetic powder such as iron powder by sintering or the like. The stator core 3 has a core back 31 and teeth 32.

< 4.3.1 iron core Back 31 >

As shown in fig. 5, the core back 31 has a ring shape whose center line coincides with the central axis Cx. That is, the stator core 3 has an annular core back 31. The core back 31 has a through hole 311 extending along the central axis at the center. As shown in fig. 2, in the motor 200, the support column 100 is inserted into the through hole 311, and the core back 31 is fixed to the support column 100. For example, the support 100 is fixed to the through hole 311 by press fitting. However, the fixation of the core back 31 to the column 100 is not limited to press fitting, and a method of fixing the core back 31 to the column 100 reliably, such as bonding or welding, is widely used.

< 4.3.2 tooth 32 >)

As shown in fig. 2 and 3, the plurality of teeth 32 project radially outward from the radially outer edge of the core back 31. The teeth 32 have the same number of U-phase teeth, V-phase teeth, and W-phase teeth, respectively. In the following description, the teeth of each phase are collectively referred to as the teeth 32. As shown in fig. 4, 5, and the like, the stator core 3 has, for example, 3 teeth 32 for each phase, and a total of 9 teeth 32. In the stator 2, the U-phase teeth 32, the V-phase teeth 32, and the W-phase teeth 32 are arranged in this order in the counterclockwise direction when viewed from above. That is, the stator core 3 has a plurality of teeth 32 extending in the radial direction from the core back 31 and arranged in the circumferential direction.

As shown in fig. 4 and 5, the tooth 32 includes an inner tooth 321, a connecting portion 322, a 1 st outer tooth 323, a 2 nd outer tooth 324, and a 3 rd outer tooth 325. That is, the tooth 32 has 1

inner tooth

321 and 3

outer teeth

323, 324, 325. The number of the internal teeth 321 is not limited to 1, and may be plural.

The number of external teeth is not limited to 3, and may be 3 or more. In consideration of the structure in which the teeth 32 are radially arranged from the core back 31, the ease of winding the wire, and the like, the number of inner teeth 321 is preferably smaller than the number of outer teeth. That is, the number of the internal teeth 321 is smaller than the number of the

external teeth

323, 324, 325. By setting the number of the internal tooth portions 321 to a smaller number than the number of the

external tooth portions

323, 324, 325, the wire winding operation can be performed efficiently. This can improve productivity.

The inner tooth 321 has a columnar shape protruding radially outward from the outer peripheral surface of the core back 31. The coupling portion 322 is connected to the radially outer edge of the internal gear portion 321. The coupling portion 322 extends from the radially outer edge of the internal gear portion 321 to both circumferential sides. As shown in fig. 5, 6, and the like, inclined portions 3221 are provided at both circumferential ends of the coupling portion 322. The inclined portion 3221 is inclined toward the center of the coupling portion 322 in the circumferential direction as it goes radially inward.

That is, both circumferential end portions of the coupling portion 322 have inclined portions 3221, and the inclined portions 3221 are inclined toward the circumferential center side of the coupling portion as they go radially inward. In the stator core 3 of the present embodiment, the inclined portion 3221 has a curved surface shape, but is not limited thereto. The shape may be a flat shape or a shape in which a plurality of planes are arranged, as long as the radially inner side is inclined toward the center of the coupling portion 322 in the circumferential direction.

When the connecting portion 322 is viewed from the internal teeth 321, the 1 st external teeth 323 project radially outward from the left end of the connecting portion 322. When the connecting portion 322 is viewed from the internal teeth 321, the 3 rd external teeth 325 protrude radially outward from the right end of the connecting portion 322. The 2 nd outer tooth portion 324 is circumferentially arranged at an intermediate portion between the 1 st outer tooth portion 323 and the 3 rd outer tooth portion 325. A center line extending in the radial direction of the 2 nd external tooth portion 324 is circumferentially coincident with a center line extending in the radial direction of the internal tooth portion 321.

That is, the tooth portion 32 extends from the radially inner side to the radially outer side along the inner tooth portion 321. The radially outer end of the internal gear 321 is connected to the coupling 322. The coupling portion 322 extends in the circumferential direction, and the 1 st, 2 nd, and 3 rd

outer tooth portions

323, 324, and 325 extend radially outward from the outer circumferential surface of the coupling portion 322. The 1 st, 2 nd, and 3 rd

outer teeth

323, 324, and 325 are arranged at equal intervals in the circumferential direction.

That is, each tooth 32 has: an inner tooth portion 321 extending radially from a radially outer surface of the core back portion 31; a coupling portion 322 connected to a radially outer end of the internal gear portion 321 and extending in the circumferential direction; and 3 or more

outer teeth

323, 324, 325 extending radially outward from the radially outer surface of the coupling portion 321 and arranged in the circumferential direction.

A plurality of (here, 9) teeth 32 are arranged at equal intervals in the circumferential direction. At this time, all the

outer teeth portions

323, 324, 325 are arranged at equal intervals in the circumferential direction on the radially outer surface of the coupling portion 321. That is, the interval between the 1 st outer tooth 323 and the 3 rd outer tooth 325 in the adjacent tooth 32 in the circumferential direction is the same as the interval between the 1 st outer tooth 323 and the 2 nd outer tooth 324 and the interval between the 2 nd outer tooth 324 and the 3 rd outer tooth 325 in the same tooth 32. That is, the stator core 3 has 9 inner teeth portions and 27 outer teeth portions.

As shown in fig. 3 to 6, the radial tips of the 1 st, 2 nd, and 3 rd

outer tooth portions

323, 324, and 325 include umbrella portions 326 extending on both circumferential sides.

< 4.4 insulating part 4 >

As shown in fig. 4, the insulating member 4 is a resin molded body. The insulator 4 insulates the stator core 3 and the coil portion 5. Although details will be described later, the coil portion 5 is formed by winding a conductive wire around each of the internal tooth portions 321, 1 st

external tooth portion

323, 2 nd

external tooth portions

324, and 3 rd external tooth portions 325 of the tooth portion 32. Therefore, the insulator 4 covers at least the inner tooth 321, the connecting portion 322, the 1 st outer tooth 323, the 2 nd outer tooth 324, and the 3 rd outer tooth 325.

In the present embodiment, the insulating material 4 is a resin molded body, but is not limited thereto. A structure capable of insulating the stator core 3 and the coil portion 5 can be widely adopted.

As shown in fig. 4, the cover portion 40 of the insulator 4 which covers the coupling portion 322 of the tooth portion 32 in the axial direction has a protruding portion 41 which protrudes upward in the axial direction from the axial upper surface. The protrusion 41 is wound with a lead wire constituting the coil unit 5, although the details will be described later. Further, wall portions 42 projecting axially upward and downward are provided on the axially upper and lower surfaces of the insulator 4 in portions that axially overlap with both ends in the radial direction of each of the internal tooth portions 321, the 1 st external tooth portion 323, the 2 nd external tooth portion 324, and the 3 rd external tooth portion 325 (see fig. 4 and 6). In the present embodiment, the cover 40 covers the upper surface of the coupling portion 322 in the axial direction, but the present invention is not limited to this. The cover 40 may cover the axial lower surface of the connection portion 322. At this time, the protrusion 31 protrudes axially downward from the axially lower surface of the cover 40.

That is, the stator 2 further has an insulator 4 covering the stator core 3. The insulator 4 covers at least one of the axial end surfaces of the connection portion 322 of the stator core 3. The insulator 4 has a protruding portion 41 protruding in the axial direction in a portion covering the coupling portion 322. When the projecting portion 41 projects downward in the axial direction, it may be configured to hold the wiring substrate 7.

< 4.5 coil part 5 >

The coil portion 5 is formed by winding a conductive wire around each of the internal tooth portion 321, the 1 st external tooth portion 323, the 2 nd external tooth portion 324, and the 3 rd external tooth portion 325 of the tooth portion 32. The coil part 5 includes an inner coil part 51, a 1 st outer coil part 52, a 2 nd outer coil part 53, and a 3 rd outer coil part 54. The 1 st outer coil part 52 is formed by winding a conductive wire around the 1 st outer tooth part 323. The 2 nd outer coil part 53 is formed by winding a wire around the 2 nd outer tooth part 324. The 3 rd outer coil portion 54 is formed by winding a wire around the 3 rd outer teeth 325.

That is, the coil section 5 includes: an inner coil portion 51 formed by winding a wire around the inner tooth portion 321; and a plurality of

outer coil portions

52, 53, 54 formed by winding a wire around the

outer teeth portions

323, 324, 325.

The 1 st outer coil part 52, the 2 nd outer coil part 53, and the 3 rd outer coil part 54 contact the connecting portion 322 of the insulator 4, the portion of the umbrella 326, and the wall 42 of the insulator 4 at both ends in the radial direction. Thus, since both ends in the radial direction of the coil are supported by the insulator 4, the 1 st outer coil part 52, the 2 nd outer coil part 53, and the 3 rd outer coil part 54 are not easily deformed.

Further, both ends in the radial direction of the inner coil portion 51 formed in the internal tooth portion 321 are in contact with the portion of the insulator 4 covering the core back portion 31 and the connection portion 322 and the wall portion 42 of the insulator 4. Accordingly, the inner coil section 51 is also less likely to deform, as are the

outer coil sections

52, 53, and 54.

Since the inner coil portion 51, the 1 st outer coil portion 52, the 2 nd outer coil portion 53, and the 3 rd outer coil portion 54 of the coil portion 5 are not easily deformed, variations in rotation and output of the motor 200 are not easily generated, and stable driving is possible. Further, with such a configuration, the coil is not easily deformed even in the process of winding the lead wire. Therefore, the workability of the step of winding the wire can be improved.

The coil portion 5 of the stator 2 of the present embodiment is formed by winding 1 wire in the order of the internal tooth portion 321, the 1 st external tooth portion 323, the 2 nd external tooth portion 324, and the 3 rd external tooth portion 325 of the tooth portion 32. Next, a method of winding the wire will be described with reference to the drawings. In the following description of the method of winding the conductive wire, the left-right direction is defined with reference to the tooth portion 32 of fig. 6.

First, the winding direction of the conductive wire will be described with reference to the inner coil portion 51. In the state shown in fig. 6, the conductive wire is extended downward on the left side of the inner tooth 321. Then, the wire is extended to the right side of the inner tooth portion 321 below the axial direction of the inner tooth portion 321. Next, the lead wire is extended upward on the left side of the inner tooth 321. Then, the wire is extended to the left side of the inner tooth portion 321 in the axial direction of the inner tooth portion 321. That is, when the inner tooth portion 321 is viewed in the radial direction from the radially inner side, the wire is wound around the inner tooth portion 321 in the counterclockwise direction. The winding direction of the wire is set to be clockwise winding or counterclockwise winding, with reference to the winding direction of the wire as viewed from the radially inner side toward the radially outer side.

Then, winding is performed closely beside the radial direction of the previously wound wire. The action of winding the wire alongside the wire is referred to as a winding advance. In the inner coil portion 51, the conductive wire is wound and advanced from the radially inner side toward the radially outer side. Then, when reaching the radially outer side, the wire is wound around the wire that has been wound, and is wound and advanced from the radially outer side to the radially inner side. In this way, the inner coil portion 51 includes a plurality of layers of windings in the thickness direction with reference to the surface of the inner tooth portion 321. The winding formed by winding and advancing the wire from one end to the other end in the radial direction is referred to as a winding layer.

The inner coil portion 51, the 1 st outer coil portion 52, the 2 nd outer coil portion 53, and the 3 rd outer coil portion 54 are wound by forming a plurality of winding layers on the inner tooth portion 321, the 1 st outer tooth portion 323, the 2 nd outer tooth portion 324, and the 3 rd outer tooth portion 325 covered with the insulator 4.

In the coil portion 5, the inner coil portion 51 has 4 winding layers. The 1 st, 2 nd, and 3 rd

outer coil portions

52, 53, and 54 have 2 winding layers. The number of windings of the inner coil part 51, the 1 st outer coil part 52, the 2 nd outer coil part 53, and the 3 rd outer coil part 54 is not limited to the above. That is, the inner coil portion 51 and the

outer coil portions

52, 53, and 54 are each formed by winding a wire in a plurality of layers. The number of windings of the inner coil section 51 is larger than the number of windings of the

outer coil sections

52, 53, 54.

The lead wires forming the coil portion are connected to a wiring board 7, which will be described later, provided axially below the stator 2. That is, in the stator 2, the lead wire is connected to the wiring substrate 7. Then, the wire is wound from the core back 31 side. That is, in the coil portion 5, the end portion where the winding of the wire starts is disposed on the core back portion 31 side.

Then, the wire is wound around the inner tooth 321 and then is radially reciprocated 1 and a half times. Then, the lead wire is drawn out as a 1 st tab 50a from the right side of the internal tooth portion 321 toward the upper portion in the axial direction of the cover portion 40 of the insulator 4. Here, the bonding wire is a portion of the conductive wire arranged in the coil portion 5, which passes through the upper portion in the axial direction of the cover portion 40 of the insulator 4 and connects the inner coil portion 51, the 1 st outer coil portion 52, the 2 nd outer coil portion 53, and the 3 rd outer coil portion 54. That is, in the coil part 5 of the present embodiment, the conductive wires forming the inner coil part 51, the 1 st outer coil part 52, the 2 nd outer coil part 53, and the 3 rd outer coil part 54 are connected by bonding wires at the upper portion in the axial direction of the cover part 40 of the insulator 4.

The 1 st lap wire 50a is hung on the protruding portion 41 of the insulator 4 and is arranged on the left side of the 1 st outer tooth portion 323. In fig. 6, the 1 st to 4 th wirings 50a to 50d are drawn loosely for clarifying the connection source and the connection destination, but actually hang on the protrusion 41 in a state where tension is applied. That is, the 1 st lap 50a is hung on the protruding portion 41 and a constant tension is applied to the wire, so that the slack of the already formed winding layer of the inner coil portion 51 can be suppressed. In order to suppress the slack, the 1 st lap 50a may be wound around the protrusion 41 for 1 or several weeks. Hereinafter, the 2 nd, 3 rd and 4

th tabs

50b, 50c and 50d may be wound around the protruding portion 41 in the same manner.

Then, the 1 st lap 50a is pulled to the left of the radially inner end portion of the 1 st outer tooth portion 323. The conductive wire continuous from the 1 st lap 50a starts to be wound around the 1 st outer tooth 323 covered with the insulator 4 from the left side of the radially inner end portion of the 1 st outer tooth 323. In the 1 st outer tooth 323, the wire is wound in the counterclockwise direction like the inner coil portion 51.

Then, the wire is wound once again and again in the radial direction on the 1 st outer tooth portion 323. Thus, the 1 st outer coil portion 52 having 2 winding layers is formed in the 1 st outer tooth portion 323.

The conductive wire wound around the 1 st outer coil part 52 is drawn out from the right side of the 1 st outer tooth part 323 to the upper surface of the cover 40 of the insulator 4 as the 2 nd lap 50 b. The 2 nd lap 50b is pulled to the right of the radially inner end of the 2 nd external tooth portion 324 after being caught on the projecting portion 41.

The conductive wire continuous from the 2 nd lap 50b is wound from the right side of the radially inner end portion of the 2 nd external tooth portion 324 to the 2 nd external tooth portion 324 covered with the insulator 4. In the 2 nd external tooth portion 324, the wire is wound in the clockwise direction opposite to the inner coil portion 51. Then, the wire winds around and advances in the 2 nd external tooth portion 324 once in the radial direction. Thereby, the 2 nd outer coil portion 53 having 2 winding layers is formed on the 2 nd outer tooth portion 324.

The conductive wire wound around the 2 nd outer coil part 53 is drawn out from the left side of the 2 nd outer tooth part 324 to the upper surface of the cover part 40 of the insulator 4 as the 3 rd lap 50 c. After the 3 rd lap 50c is caught by the projection 41, it is pulled to the left of the radially inner end of the 3 rd outer tooth 325.

The conductor continuous from the 3 rd lap 50c starts to be wound around the 2 nd outer tooth 324 covered with the insulator 4 from the left side of the radially inner end portion of the 3 rd outer tooth 325. In the 3 rd outer tooth 325, the wire is wound in the counterclockwise direction like the inner coil part 51. Then, the wire is wound once in a radial direction in the 3 rd outer tooth 325. Thereby, the 3 rd outer coil part 54 having 2 winding layers is formed on the 3 rd outer tooth part 325.

The conductive wire wound around the 3 rd outer coil part 54 is drawn out from the right side of the 3 rd outer tooth part 325 to the upper surface of the cover 40 of the insulator 4 as the 4 th lap 50 d. The 4 th jumper 50d is pulled to the left of the radially outer end of the inner tooth portion 321 after being hung on the projection 41.

The wire continuous from the 4 th lap 50d starts to be wound around the inner tooth portion 321 covered with the insulator 4 from the left side of the radially outer end portion of the inner tooth portion 321. In the inner tooth 321, the wire is wound in the counterclockwise direction. Then, the wire is wound to advance to the radially inner side. Thereby, the inner coil portion 51 having 4 winding layers is formed on the inner tooth portion 321.

By hanging the wires on the protruding portion 41 of the insulator 4, the

lap wirings

50a, 50b, 50c, 50d spanning the inner coil portion 51, the outer coil portion 52, and the

outer coil portions

52 and 53, and 54 from each other are easily formed.

In the coil unit 5, the inner coil portion 51, the 1 st outer coil portion 52, the 2 nd outer coil portion 53, and the 3 rd outer coil portion 54 are formed by 1 wire. That is, the inner coil portion 51 and the plurality of

outer coil portions

52, 53, and 54 are formed of 1 wire.

When the wire is stretched between the coil portions, the wire is caught by the protruding portion 41, and thereby winding disorder such as slackening of the wire in each coil portion is suppressed. By winding the conductive wire as described above, both the winding start side end portion and the winding end side end portion of the conductive wire can be positioned radially inward of the teeth 32. This facilitates the work of mounting the lead on the wiring board 7.

As described above, in the coil unit 5, the inner coil portion 51, the 1 st outer coil portion 52, and the 3 rd outer coil portion 54 are wound in the counterclockwise direction. On the other hand, the 2 nd outer coil portion 53 is wound in the clockwise direction. That is, the winding directions of the wires of the

outer coil portions

323, 324, 325 adjacent in the circumferential direction are opposite to each other. Each tooth 32 has 1

inner tooth

321 and 3

outer teeth

323, 324, and 325 arranged in a row in the circumferential direction. The winding direction of the lead wire of the outer coil portion 53 disposed at the circumferential center is opposite to the winding direction of the lead wire of the inner coil portion 51.

By configuring the teeth 32 in this manner, the flow of the magnetic force generated by the inner coil portion 51 and the

outer coil portions

52, 53, and 54 can be smoothed. This can increase the output torque of the motor 200.

< 4.6 Wiring substrate 7 >

The motor 200 includes a wiring substrate 7, and the wiring substrate 7 is formed with a wiring for supplying a current to the coil portion 5. As shown in fig. 2, the wiring board 7 is disposed axially below the stator 2. As described above, in the stator 2, the inner coil portion 51 has more winding layers than the

outer coil portions

52, 53, and 54. Therefore, in the stator 2, the thickness of the radial outer side is thinner than that of the inner side. That is, a gap is formed between the lower portions of the

outer coil portions

52, 53, and 54 and the impeller casing 301 axially below the stator 2. The wiring board 7 is disposed in the gaps below the

outer coil portions

52, 53, and 54.

Since the wiring board 7 is disposed axially below the

outer coil portions

52, 53, and 54 and the electronic components are housed in the gaps between the lower portions of the

outer coil portions

52, 53, and 54 and the impeller housing 301, the thickness of the motor 200 in the axial direction can be reduced. This can reduce the thickness of the motor 200 in the axial direction. A detection element, such as a hall element or a hall sensor, for detecting the magnetism of the rotor magnet 13 of the rotor 1 to detect the rotation angle (speed) of the rotor 1 is mounted on the wiring substrate 7. Since the wiring board 7 is disposed radially outward of the stator 2, the detection element can be disposed in the vicinity of the rotor magnet 13. This enables the position of the rotor 1 to be detected with high accuracy.

< 4.7 details of the motor 200 >

As shown in fig. 2, the rotor 1 is mounted to the rotor mounting portion 307 of the impeller housing 301. The rotor 1 may be fixed to the rotor mounting portion 307 by press-fitting the rotor case 12 into the rotor mounting tube portion 309 of the rotor mounting portion 307, or may be fixed by a fixing method such as adhesion or welding.

Then, after the wiring board 7 is attached to the base portion 101 of the column 100, the stator 2 is attached to the column 100. The impeller housing 301 is rotatably mounted on the support 100 provided with the stator 2 and the wiring board 7 via the bearing 6. At this time, the rotor magnet 13 radially faces the

external teeth

323, 324, 325 of the teeth 32 of the stator 2.

Then, by supplying a current to the coil part 5, the inner coil part 51, the 1 st outer coil part 52, the 2 nd outer coil part 53, and the 3 rd outer coil part 54 are excited. The rotor 1 is rotated by the attractive and repulsive forces of the

outer coil portions

52, 53, 54 and the rotor magnet 13.

< 4.8 excitation of coil part 5 >

The state of the magnetic force when the current flows through the coil portion 5 having the winding direction shown above will be described with reference to the drawings. Fig. 7 is a diagram illustrating flows of magnetic forces generated when current flows through the inner coil portion and the outer coil portion of the tooth portion. In fig. 7, the flow of the magnetic force is indicated by arrows. The magnetic force is generated by supplying an electric current to the coil portion 5. In fig. 7, a current flowing from the 1 st outer coil part 52 to the 2 nd outer coil part 53 is provided. Thereby, the radially inner sides of the inner coil part 51, the 1 st outer coil part 52, and the 3 rd outer coil part 54 are excited to N-poles. The radially outer side of the 2 nd outer coil portion 53 is excited to the N pole.

In the connecting portion 322, a portion where the internal tooth portion 321 and the 2 nd external tooth portion 324 are connected is an S pole. In the connection portion 322, the portion where the 1 st outer tooth 323 and the 3 rd outer tooth 325 are connected is an N-pole. The magnetic beam flows from the N pole toward the S pole. Therefore, in the connection portion 322, the magnetic force flows from the portion where the 1 st and 3 rd

outer teeth

323 and 325 are connected to each other to the portion where the inner teeth 321 and the 2 nd outer teeth 324 are connected to each other. As shown in fig. 7, the flow of the magnetic force is symmetrical about the center line in the tooth portion 32. Here, the symmetry also includes substantial symmetry.

The tooth portion 32 has a structure in which 2-stage teeth are arranged in the radial direction on the inner tooth portion 321 and the

outer tooth portions

323, 324, and 325. This can narrow the interval between the

external teeth

323, 324, 325 disposed on the outer periphery of the stator 2. Therefore, the teeth can be increased without increasing the outer diameter of the stator core 3. This increases the number of windings of the coil of each phase, and can increase the output torque of the motor 200 without increasing the size of the stator 2 (motor 200).

Further, the flow of the magnetic force in the coupling portions 322 of the teeth 32 can be adjusted by winding the wire in a direction different from that of the inner coil portion 51 only for the 2 nd outer coil portion 53 formed on the 2 nd outer tooth portion 324 which is the circumferentially inner outer tooth portion among the 3 outer tooth portions. That is, when the stator core 3 is used, the magnetic force generated in the inner coil portion 51 can be effectively utilized, and the magnetic force generated in the coil portions 5 formed in the tooth portions 32 can be increased. This can increase the output torque of the motor 200.

In the tooth portion 32, the connection portion 322 has an inclined portion 3221. This allows the magnetic force flowing in the connecting portion 322 to flow smoothly, and prevents the magnetic force from leaking to the outside of the tooth portion 32. Therefore, the magnetic force generated in the coil section 5 can be efficiently used. This can increase the output torque of the motor 200.

In the stator of the present embodiment, the number of windings of the teeth can be increased without increasing the outer diameter of the stator core. Thus, in the case of motors having the same outer shape and size, a larger torque can be output by using the stator of the present embodiment. In addition, in the case of a motor that outputs the same torque, the stator can be made smaller, and therefore the motor itself can be made smaller.

That is, by using the stator of the present embodiment, the output torque can be increased without increasing the outer shape of the motor. Further, the motor can be downsized while maintaining the output torque.

< 5. variants, etc. >

A modified example of the stator of the present invention will be described with reference to the drawings. Fig. 8 is a plan view showing a modification of the stator core. The core back 31a of the stator core 3a shown in fig. 8 is different in structure from the core back 31 of the stator core 3. Otherwise, the stator core has the same structure as the stator core 3 shown in fig. 5 and the like. Therefore, in the stator core 3a, the same reference numerals are given to substantially the same portions as the stator core 3, and detailed description of the same portions is omitted.

The core back 31a of the stator core 3a shown in fig. 8 has 9 separable core backs 312, which are the same number as the teeth 32. The split core back 312 is formed of the same member as the tooth portion 32. The member including the tooth portion 32 and the split core back portion 312 is referred to as a split core 33. Further, 1 divided core back 312 is connected to 1 tooth 32, but the present invention is not limited thereto. For example, 1 divided core back 312 may be connected to a plurality of teeth 32.

That is, the core back portion 31a is formed by connecting a plurality of divided core back portions 312 in the circumferential direction, and at least 1 tooth portion 32 is connected to the radially outer side of the divided core back portions 312.

The stator core 3a is formed by combining 9 divided cores 33 in the circumferential direction. The stator core 3a can be divided into 9 divided cores 33. By configuring the tooth portion 32 to include the inner tooth portion 321, the connecting portion 322, the 1 st outer tooth portion 323, the 2 nd outer tooth portion 324, and the 3 rd outer tooth portion 325, the number of the connecting portions of the divided cores can be reduced as compared with the case where the stator core is divided into teeth. This reduces errors due to the accumulation of dimensional tolerances, and improves productivity.

The motor of the present invention is widely used not only as an air blower but also as a power source for rotating a rotating body.

The embodiments of the present invention have been described above, but the present invention is not limited to the above. The embodiments of the present invention can be variously modified without departing from the gist of the invention.

Industrial applicability

The air supply device of the present invention may be used for a circulator. And, for example, may be used as a power source for an unmanned aerial vehicle. In addition, the present invention can be widely applied to a device using an airflow generating an axial flow. The motor of the present invention can be used as a power source for supplying a rotational force to the outside, in addition to the blower.

Claims

1. A stator, having:

a stator core; and

a coil portion formed by winding a wire around a portion of the stator core,

wherein,

the stator core has:

an annular iron core back; and

a plurality of teeth connected to the core back at a radially outer side and arranged in a circumferential direction,

each of the tooth portions has:

an inner tooth portion extending radially outward from a radially outer surface of the core back portion;

a connection portion connected to a radially outer end of the inner tooth portion and extending in a circumferential direction; and

3 or more outer teeth extending radially outward from a radially outer surface of the coupling portion and arranged in a circumferential direction,

the coil portion includes:

an inner coil portion formed by winding a conductive wire around the inner tooth portion; and

a plurality of outer coil portions formed by winding a conductive wire around the outer teeth portions,

in each of the teeth, the inner coil part and the plurality of outer coil parts are formed of 1 wire.

2. The stator according to claim 1,

the winding directions of the conductive wires of the circumferentially adjacent outer coil portions are mutually opposite directions.

3. The stator according to claim 1 or 2,

the number of the inner teeth portions is smaller than that of the outer teeth portions.

4. The stator according to claim 1 or 2,

each of the tooth portions has:

1 inner tooth portion; and

3 outer teeth arranged in a circumferential direction,

the winding direction of the wire of the outer coil portion arranged at the circumferential center is opposite to the winding direction of the wire of the inner coil portion.

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

the circumferential both ends of the coupling portion have inclined portions that incline toward the circumferential center side of the coupling portion as they go radially inward.

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

the core back is formed by connecting a plurality of divided core backs along the circumferential direction,

at least 1 tooth is connected to the radially outer side of the back of the divided core.

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

the stator further has an insulator covering the stator core,

the insulator covers at least one of axial end surfaces of the coupling portion of the stator core,

the insulator has a protruding portion protruding in the axial direction in a portion covering the coupling portion.

8. The stator according to any one of claims 1 to 7,

the inner coil part and the outer coil part are each formed by winding a conductive wire in a plurality of layers,

the number of layers of the windings of the inner coil part is greater than the number of layers of the windings of the outer coil part.

9. A motor, comprising:

the stator of any one of claims 1 to 8; and

and a rotor that is radially opposed to the stator and is supported to be rotatable with respect to the stator.

10. An air supply device includes:

the motor of claim 9; and

an impeller attached to the rotor.