JP2001112193A - Motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem of a maximum magnetic field strength H being not applied to the surface of a rotor because the magnetic field strength H has an angle with reference to a magnetic flux density B, when the direction of the magnetic flux density B and that of the magnetic field strength H do not always agree, and when the magnetic field strength H differs according to the kind of a material or the magnitude of the magnetic flux density B, i.e., when teeth are continued to be directed toward the central direction of the rotor in a motor in conventional cases. SOLUTION: In this motor, a rotor 1 is provided, and a stator 2 which is arranged so as to face the rotor 1 is provided. The angle of inclination of a magnetic field strength H, passing a part between a tooth 6 and a tooth 6, is formed at a nearly identical angle with reference to the radial direction which passes the center of the rotor 1, and the iron loss of the motor is low by making use of the magnetic field strength efficiently.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotor, in which the inclination angle of teeth of a stator is substantially the same as the direction of a magnetic field, thereby suppressing torque ripple, reducing iron loss, reducing copper loss, and improving efficiency. The present invention relates to an effective electric motor.

[0002]

2. Description of the Related Art A conventional synchronous motor is shown in FIG. A rotor 51, disposed on the outer periphery of the rotor,
A stator 52 having a primary conductor 55 wound in each slot 54 and a shaft 53, and a gap 5 is provided between the rotors 51 so that the rotor 51 can rotate.
7 are provided. The rotor 51 has a permanent magnet 58 attached to the outer peripheral surface thereof. At this time, the stator 52
The teeth 56 are directed toward the center of the rotor 51 and have no inclination angle.

[0003]

According to recent research,
As shown in FIG. 2, it is known that the directions of the magnetic flux density B and the magnetic field strength H do not always match, and differ depending on the type of material and the magnitude of the magnetic flux density B. In other words, if the teeth are oriented toward the center of the rotor as in a conventional motor, the maximum magnetic field strength H is not applied to the surface of the rotor because the magnetic field strength H is at an angle to the magnetic flux density B. .

[0004] In view of the fact that the directions of the magnetic flux density B and the magnetic field strength H do not always coincide with each other, an object of the present invention is to provide a motor that is driven to rotate with high efficiency.

[0005]

SUMMARY OF THE INVENTION Accordingly, the present invention provides an electric motor having a rotor and a stator arranged opposite to the rotor, wherein the inclination angle of the teeth and the magnetic field strength H passing through the teeth is set to the above-mentioned value. The rotor is formed to have substantially the same angle with respect to the radial direction passing through the center of the rotor, and it is intended to provide a motor with low iron loss by effectively utilizing the magnetic field strength.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An electric motor according to the present invention comprises a rotor,
A stator disposed opposite to the rotor, wherein the teeth of the stator are inclined with respect to a radial direction passing through the center of the rotor, and the inclination angle α of the teeth is
Is substantially the same as the angle difference β between the direction of the magnetic field passing through the teeth and the direction of the magnetic flux density. Since the magnetic field strength H is perpendicular to the outer periphery of the rotor, the magnetic field strength can be used effectively. Furthermore, a plurality of teeth of the stator are inclined,
Other teeth may be configured to go straight to the rotor.

Further, the electric motor of the present invention includes a rotor and a stator disposed opposite to the rotor, and a slot between the slots is inclined with respect to a radial direction passing through the center of the rotor. The inclination angle α ′ of the inter-slot portion is driven by an induction method in which the angle difference β ′ between the direction of the magnetic field passing through the inter-slot portion and the magnetic flux density direction is substantially the same, and the magnetic field intensity H generated from the rotor is You can enter the inside of the vertical. Further, it is preferable that the inter-slot portion is inclined in the rotation direction of the rotor.

[0008]

FIG. 1 shows an embodiment of a synchronous motor having a permanent magnet. Stator 2, rotor 1 and shaft 3
And a gap 7 is provided between the stator 2 and the rotor 1 so that the rotor 1 can rotate. A primary winding 5 is provided in each slot 4. The rotor 1 has a permanent magnet 8 attached to its outer peripheral surface. Also,
The teeth 6 have an inclination angle β with respect to a straight line 11 passing through the center of the rotor 1. The straight line 12 is a center line where the teeth 6 are directed to the outer peripheral surface of the rotor 1 and is a straight line passing through the middle of the adjacent slots 4.

Primary winding 5 in which stator 2 is distributed-wound
Then, a magnetic flux is generated in the stator 2 by passing a current. This magnetic flux passes through the gap 7 from the teeth 6 of the stator 2 and forms a magnetic path in the rotor 1. Since the magnetic flux passes through the shortest distance, the magnetic flux passing through the teeth 6 is oriented in a direction perpendicular to the rotor 2.

The feature of this embodiment is that the teeth 6 are inclined with respect to the outer periphery of the rotor 1 at an inclination angle α in the rotation direction of the rotor 1.

FIG. 3 shows the structure of a conventional motor.
The direction of the teeth is the same as the radial direction passing through the center of the rotor. In such a configuration, the magnetic field density B is the same as the teeth direction, but the direction of the magnetic field strength H is inclined with respect to the magnetic field density B by an angle α. This angle α is inclined in the direction opposite to the rotation direction of the rotor, and varies depending on the material of the teeth.
° inclination.

In this embodiment, as shown in FIG.
Is inclined in the rotation direction of the rotor 1 so that the magnetic field strength H
In a direction perpendicular to the outer periphery of the rotor 1,
Since the direction of the magnetic field strength H is the same as the direction of the teeth 6, the inclination angle β of the teeth 6 is determined by the magnetic field strength H and the magnetic flux density B.
Is approximately the same (| α−β | <5 °), the maximum magnetic field strength H can be input to the surface of the rotor 2. As a result, a large magnetic field is generated with a small current, so that the iron loss can be reduced with respect to the magnitude of the torque.

Although the electric motor shown in the embodiment can rotate in both forward and reverse directions, it is preferable that the electric motor rotates mainly in the forward direction (R direction).
Because it is difficult for the direction of the teeth to move in accordance with the rotation of the rotor, it is preferable that the teeth rotate in one direction.

The winding of the stator may be either concentrated winding or distributed winding. Further, the stator may be a stator and a split core obtained by connecting a stator core 81 as shown in FIG.

(Embodiment 2) Embodiment 2 is an electric motor as shown in FIG. 5, in which a plurality of teeth 21 are inclined at an inclination angle β, and the other teeth 22 are not inclined. Perpendicular to the surface. The inclination angle of the teeth may be different between the main winding part and the auxiliary winding part in the single-phase motor.

(Embodiment 3) Embodiment 3 is an electric motor as shown in FIG. 6, in which a secondary conductor 31 is embedded in a rotor. The teeth 6 have the inclination angle of a straight line 12 having an inclination angle β with respect to a straight line 11 passing through the center of the rotor 1. Similar effects can be obtained with an induction motor as with a synchronous motor.

Further, the secondary conductor 31 is inclined by 31 with respect to a radial straight line 32 passing through the center of the rotor by an inclination angle β ′, and the inclination angle β ′ is determined by the magnetic flux intensity H and the magnetic flux density B generated in the secondary conductor. And the angle difference α ′ may be substantially the same, and the magnetic flux intensity H may be input perpendicularly to the inner circumference of the stator 2.

[0018]

As described above, according to the present invention, at least one of the teeth portion of the stator and the slot portion of the rotor is formed to have substantially the same inclination angle as the magnetic field direction with respect to the radial direction passing through the center of the rotor. Therefore, the reduction of the magnetic loss can suppress torque ripple, reduce iron loss, reduce copper loss, and improve efficiency.

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of the present application.

FIG. 2 is a conceptual diagram showing an angle difference between a magnetic flux density B and a magnetic field strength H.

FIG. 3 is an enlarged view of the teeth of FIG. 1;

FIG. 4 is an enlarged view of the teeth of FIG. 2;

FIG. 5 is a plan view of the second embodiment.

FIG. 6 is a plan view of the third embodiment.

FIG. 7 is a plan view of another electric motor according to the third embodiment.

FIG. 8 is a plan view of a split core of the stator.

FIG. 9 is a sectional view of a conventional electric motor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rotor 2 Stator 3 Axis 4 Slot 5 Primary winding 6 Teeth 7 Gap 8 Permanent magnet 9 Secondary conductor

Claims (8)

[Claims] 1. A stator comprising: a rotor; and a stator disposed opposite to the rotor, wherein teeth of the stator are inclined with respect to a radial direction passing through a center of the rotor, and an inclination angle α of the teeth is An electric motor having substantially the same angle as the angle difference β between the direction of the magnetic field passing through the teeth and the direction of the magnetic flux density. 2. The electric motor according to claim 1, wherein the teeth are inclined in a rotation direction of the rotor. 3. A plurality of stator teeth are inclined,
2. The electric motor according to claim 1, wherein the other teeth travel straight with respect to the rotor. 4. A rotor comprising: a rotor; and a stator disposed to face the rotor, wherein an inter-slot portion of the rotor is inclined with respect to a radial direction passing through a center of the rotor.
An electric motor driven by an induction method in which the inclination angle α ′ of the inter-slot portion is substantially the same as the angle difference β ′ between the direction of the magnetic field passing through the inter-slot portion and the direction of the magnetic flux density. 5. The electric motor according to claim 4, wherein the inter-slot portion is driven by an induction method inclined in the rotation direction of the rotor. 6. A compressor comprising the electric motor according to claim 1 or 4, wherein the electric motor performs a compression operation. 7. An air conditioner comprising the electric motor according to claim 1 or 4 and performing heat exchange by the electric motor. 8. A fan device comprising the motor according to claim 1 or 4, wherein the motor rotates a propeller in only one direction.