JPH11275781A - Structure of stator of motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the size of a motor and prevent torque drop, by building up a stator core from a cylindrical outside core and a plurality of divided cores, which are so fixed on the inner surface of the outside core as to be adjacent to each other in the circumferential direction, and each of which is provided with a tooth section to be wound with a coil. SOLUTION: A stator core 6 is constituted of a cylindrical outside core 8 and a plurality of divided cores 9, which are so fixed on the inner surface of the outside core 8 as to be adjacent to each other in the circumferential direction, and each of which has a tooth 9e to be wound with a coil. Due to this structure, while the cores 9 are of a divided structure allowing each tooth 9e to be easily wound with a coil, the outside core 8 to which the divided cores 9 are fixed forms a magnetic path. Therefore, required magnetic flux can be secured without increasing the size of the outer diameter of the brushless motor 1 or reducing a slot area.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of motors used for electric components of vehicles.

[0002]

2. Description of the Related Art In general, among such motors, there is a so-called brushless motor in which a stator having a coil wound around a stator core is disposed on the outer peripheral side of a rotor having a permanent magnet. In this case, it is common practice to divide the stator core for each tooth and integrate the divided cores by welding. However, since there is a possibility that a loss may be caused by welding, as shown in FIG. 7, the applicant assigns a plurality of divided cores 14 divided for each tooth 14a.
Are arranged in the circumferential direction on the inner peripheral surface portion of the cylindrical aluminum case 15 and fixed by an adhesive.

[0003]

In the motor having the split core structure, the case to which the split core is fixed is made of aluminum as described above, so that no magnetic circuit is formed. Is smaller than the outer diameter of the motor. In such a split core structure, in order to secure the same magnetic flux as that of a normal core structure that is not divided in the circumferential direction, the diameter of the stator core is set to the diameter of the stator core of the normal core structure. It is necessary to set equal or to set the volume of the slot smaller than the slot volume of the normal core structure. However, when the diameter of the stator core is set equal,
The split core structure has a problem that the diameter of the motor is increased by the thickness of the case as compared with the normal core structure, which leads to an increase in the size of the motor. On the other hand, when the volume of the slot is set to be small, there is a problem that the resistance of the coil becomes large, so that the copper loss increases, and the torque of the motor decreases. was there.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has been made in order to solve these problems, and has a stator core provided on the outer peripheral side of a rotor having a permanent magnet. In a motor having a stator with coils wound thereon, the stator core is fixed to a cylindrical outer peripheral core and an inner peripheral surface of the outer peripheral core in a circumferentially adjacent state, It is configured using a plurality of split cores having teeth portions around which coils are wound. By doing so, the cylindrical outer peripheral core to which the divided cores are fixed also forms a magnetic circuit without causing loss due to welding while having the divided core structure, The required magnetic flux can be secured without increasing the outer diameter of the motor or reducing the slot area. In this case, the outer peripheral side core and the divided core are formed by laminating a plurality of steel thin plate-shaped core members in the axial direction of the rotor, so that the outer peripheral side core and the divided core are integrated into a good magnetic circuit. To form Further, the split core is oriented in an outer peripheral side portion fixed to the outer peripheral side core, an inner peripheral side portion facing the outer peripheral portion of the rotor with an air gap, and a radial direction connecting these both side portions. The outer peripheral side portions of the divided cores, which are constituted by a connecting portion and are further circumferentially adjacent to each other, are fixed to the outer peripheral side core in a state of abutting each other, so that the divided cores can be easily positioned. In addition, the circular diameter accuracy can be made high.

[0005]

Next, an embodiment of the present invention will be described with reference to the drawings. In the drawings, reference numeral 1 denotes a brushless motor. The brushless motor 1 includes a rotor 3 having a permanent magnet 2, a stator 4 disposed on an outer peripheral side of the rotor 3, and a rotation detector for detecting rotation of the rotor 3. It is composed of a member device such as the sensor 5.

The stator 4 includes a stator core 6, a coil 7 wound around the stator core 6, and the like. The stator core 6 further includes a cylindrical outer core 8 and an inner core 8. It is composed of a plurality of divided cores 9 fixed to the peripheral surface in a state of being adjacent to the peripheral direction.

The outer peripheral side core 8 is formed by laminating a plurality of thin plate-shaped core members 8a formed by punching out an electromagnetic steel plate in the axial direction of the rotor 3, and bonding the laminated core members 8a to each other by means of an appropriate fixing means such as a boss, caulking or rivets. The outer core 8 forms an outer shell of the brushless motor 1.

The split core 9 is made of a thin plate-shaped core material 9 formed by stamping out an electromagnetic steel sheet, like the outer peripheral side core 8.
a are laminated integrally in the axial direction of the rotor 3 and integrally fixed by appropriate fixing means such as bonding, bossing caulking, and rivets. An outer peripheral side portion 9b adhered to the surface portion, an inner peripheral side portion 9c facing the outer peripheral portion of the rotor 3 with a predetermined air gap, and a radial direction connecting the two side portions 9b and 9c. A connecting part 9d is provided, and the connecting part 9d and the inner peripheral side part 9c form a tooth 9e around which the coil 7 is wound.

A coil 7 is wound around the teeth 9e of each of the divided cores 9, and the outer peripheral portions 9b of the divided cores 9, 9 which are adjacent in the circumferential direction abut against each other. The stator core 6 is formed by sequentially adhering to the inner peripheral surface of the stator core 6. In the stator core 6 formed in this manner, the magnetic flux is applied to the divided cores 9 adjacent in the circumferential direction as shown by arrows in FIG.
To the split core 9 and from the split core 9 to the outer peripheral core 8
Flows to In the present embodiment, the coil 7 is wound around each tooth 9e and then connected, but the coil 7 may be wound after the stator core 6 is integrated. Reference numeral 10 denotes an insulator (insulating material) interposed between the coil 7 and the outer peripheral side portion 9b and the inner peripheral side portion 9c of the split core 9.

In the configuration described above, the stator core 6 is fixed to the outer peripheral core 8 having a cylindrical shape and the inner peripheral surface of the outer peripheral core 8 in a circumferentially adjacent state, and the coil 7 is fixed. It is configured using a plurality of split cores 9 having wound teeth 9e. As a result, the outer peripheral core 8 to which the split core 9 is fixed also forms a magnetic circuit while having a split core structure so that the coil 7 can be easily wound around the teeth 9e. The required magnetic flux can be ensured without increasing the outer diameter of the device 1 or reducing the slot area.

The divided core 9 is fixed to the outer peripheral core 8 with the outer peripheral portions 9b of the divided cores 9 adjacent in the circumferential direction abutting on each other. In addition, the positioning of the split core 9 can be easily performed, and the accuracy of the circular diameter can be increased.

In addition, the outer core 8 is divided
In the same manner as described above, the magnetic steel sheet is formed by laminating a plurality of sheets formed by punching out an electromagnetic steel sheet. Furthermore, the degree of design freedom of the shape of the outer peripheral core 8 is increased as compared with the case where the outer peripheral core is manufactured by forging, and, for example, through bolts as in the second embodiment shown in FIG. The outer peripheral core 11 in which the through hole 11a is formed, or the inner peripheral surface of the outer peripheral core 12 having a polygonal shape as in the third embodiment shown in FIG. Things can be easily manufactured. Here, in the third embodiment, the outer peripheral surface of the outer peripheral side portion 13a of the split core 13 is:
It is formed in a flat shape corresponding to the inner peripheral surface of the outer peripheral side core 12, so that the positioning and fixing of the split core 13 can be performed more easily.

Further, in the above-described embodiment, both the dividing core and the divided core are formed by using an electromagnetic steel sheet. However, the present invention is not limited to this. The side core can also be configured to improve the magnetic properties by using a non-oriented silicon steel sheet. Such a design change can be appropriately changed according to the application of the brushless motor 1 and the like. Of course you can.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view of a brushless motor.

FIG. 2A is a perspective view of a split core, and FIG. 2B is a perspective view of a split core wound with a coil.

FIG. 3 is a perspective view of an outer peripheral side core.

FIG. 4 is a plan view of a stator.

FIG. 5 is a sectional view of a stator core from which coils are omitted.

FIG. 6A is a perspective view of an outer peripheral core showing a second embodiment, and FIG. 6B is a perspective view of an outer peripheral core and a split core showing a third embodiment.

FIG. 7 is a sectional view of a stator core having a split core structure using an aluminum case.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Brushless motor 2 Permanent magnet 3 Rotor 4 Stator 6 Stator core 7 Coil 8 Outer side core 8a Core material 9 Split core 9a Core material 9b Outer side part 9c Inner side part 9d Connecting part 9e Teeth

Claims (3)

[Claims] 1. A motor having a stator in which a coil is wound around a stator core disposed on an outer peripheral side of a rotor having a permanent magnet, wherein the stator core comprises a cylindrical outer peripheral core, and the outer peripheral core. And a plurality of split cores having teeth portions around which coils are wound and which are fastened to the inner peripheral surface portion of the motor in a circumferentially adjacent state. 2. The motor stator structure according to claim 1, wherein the outer peripheral side core and the divided cores are formed by laminating a plurality of thin steel core members in the axial direction of the rotor. 3. The split core according to claim 1, wherein the split core includes an outer circumferential portion fixed to the outer circumferential core, an inner circumferential portion facing the outer circumferential portion of the rotor with an air gap, and both sides thereof. A stator structure for a motor, comprising a radially-directed connecting portion for connecting the portions, wherein the outer peripheral side portions of the divided cores adjacent in the circumferential direction are fixed to the outer peripheral core in a state of abutting each other.