JPH0543749U - Rotor of rotating magnetic field type motor - Google Patents

Abstract

(57) [Summary] [Purpose] To reduce the leakage flux generated in the gap between the permanent magnet and the pole plate flange. [Structure] A rotor fixed to a rotating shaft by sandwiching a plurality of axially magnetized permanent magnets with a magnetic pole plate having a flange portion that is unevenly distributed in the rotating direction, and a space is provided around the outer periphery of the rotor. In a rotating magnetic field type electric motor having a stator arranged in parallel, a thin auxiliary permanent magnet is fixed to the inner peripheral surface of the flange portion of the magnetic pole plate facing the outer peripheral surface of the permanent magnet with a gap. Has the same polarity as the polarity that flows to the pole plate on the side where the flange portion is fixed.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a rotor for a rotating magnetic field type motor, and particularly to improve a rotor having a claw pole type magnetic pole plate to reduce leakage flux.

[0002]

[Prior Art]

 Conventionally, an electric motor having a rotor as shown in FIG. 5 has been proposed as a rotating magnetic field type electric motor having a claw pole type magnetic pole plate in the rotor of this type. (Japanese Utility Model Laid-Open No. 61-195762) In the rotor 1 of the electric motor, the permanent magnets 3a and 3b magnetized in the axial direction are fixed to the outer periphery of the rotary shaft 2 and the permanent magnets are provided between the permanent magnets. The sandwiched magnetic pole plates 4a to 4d are fixed, and the outer peripheral flange portions of these magnetic pole plates are unevenly distributed in the rotational direction to form magnetic poles.

In the electric motor including the rotor 1, as shown in FIGS. 6 and 7, the rotor 1 is arranged inside a ring-shaped stator 5, and the inner peripheral surface of the stator 5 is spaced by a predetermined distance. The winding 7 is housed in the recess 6 formed by opening the core 7, and the iron core 8 on the end surface of the side wall of the recess is positioned at the required intervals on the flanges of the magnetic pole plates 4a to 4d that are unevenly distributed in the rotation direction.

In the above motor, the main magnetic flux X flows from the permanent magnetic pole plates 3a, 3b through the magnetic pole plates 4a, 4b, 4c, 4d to the iron core 8 as shown by the solid lines in FIGS. The rotating magnetic field generated from the line 7 causes a force to rotate the rotor 1.

[0005]

[Problems to be solved by the device]

 However, the magnetic pole plates 4a to 4d are provided with a flange portion 4-II that bends in the axial direction at the outer peripheral end of the disk portion 4-I that contacts the permanent magnets 3a and 3b, and the flange portion 4-II faces the iron piece 8. Therefore, since the inner peripheral surface of the flange portion 4-II faces the outer peripheral surfaces of the permanent magnets 3a and 3b, leakage magnetic flux is generated. That is, the leakage flux Y shown by the dotted line in the figure is generated from the magnetic pole plates 4a, 4d where the N pole magnetic flux flows to the S pole side of the permanent magnetic pole plates 3a, 3b, and similarly, the magnetic pole plate 4b where the S pole magnetic flux flows. , 4c, a leakage magnetic flux Y is generated from the N pole side of the permanent magnetic pole plates 3a, 3b.

When the leakage magnetic flux Y increases, the main magnetic flux X for rotating the rotor decreases, and as a result, the output of the rotating magnetic field type motor decreases.

In order to reduce the leakage magnetic flux, the amount of leakage can be reduced by widening the gap L between the opposing outer peripheral surface of the permanent magnet and the inner peripheral surface of the flange portion of the magnetic pole plate. If the gap L is widened, there is a problem that the electric motor becomes large. In order to widen the gap L without increasing the size of the motor, it is necessary to reduce the diameter of the permanent magnet. In this case, the absolute value of the amount of magnetic flux decreases, so the output also decreases. That is, in order to increase the output while keeping the outer diameter of the electric motor constant, it is necessary to increase the diameter of the permanent magnet to minimize the gap L with the magnetic pole plate. As described above, there arises a problem that the amount of leakage magnetic flux increases.

The present invention has been made to solve the above-mentioned problems, and eliminates the generation of leakage flux in the gap between the outer peripheral surface of the permanent magnet and the inner peripheral surface of the flange portion of the magnetic pole plate, thereby reducing the size of the motor. And higher output.

[0009]

[Means for Solving the Problems]

 That is, according to the present invention, a plurality of permanent magnets magnetized in the axial direction are sandwiched between magnetic pole plates having flanges that are unevenly distributed in the rotational direction, and the rotor is fixed to the rotational shaft. In a rotating magnetic field type motor having stators arranged at intervals, a thin auxiliary permanent magnet is fixed to an inner peripheral surface of a flange portion of a magnetic pole plate facing the outer peripheral surface of the permanent magnet with a gap, The polarities of the auxiliary permanent magnets are the same as the polarities flowing on the pole plate on the side where the flange is fixed, thereby providing a rotor.

The auxiliary permanent magnet may be formed as an arc-shaped piece fixed along the inner peripheral surface of each flange portion. Further, as a ring shape, they are fixed to the inner peripheral surfaces of the flange portions of different magnetic pole plates which are arranged at intervals on the peripheral surface in the same axial direction. In that case, the ring-shaped auxiliary permanent magnet is magnetized by changing the polarity at intervals in the circumferential direction so that the portion having the same polarity as the polarity flowing to the fixed magnetic pole plate is located on the fixed surface of the magnetic pole plate. Is set to. Further, auxiliary permanent magnets that are adjacent to each other in the axial direction may be mounted in contact with each other, or may be arranged with a gap.

[0011]

[Action]

 As described above, an auxiliary permanent magnet is attached to the inner peripheral surface of the flange of the magnetic pole plate that faces the outer peripheral surface of the permanent magnet, and the polarity of the auxiliary permanent magnet is the same as the polarity of the magnetic flux flowing through the flange fixing side. By doing so, it is possible to reduce the leakage of the magnetic flux flowing through the pole plate.

[0012]

【Example】

 Hereinafter, the present invention will be described in detail with reference to the embodiments shown in the drawings. In the first embodiment shown in FIGS. 1 and 2, a first permanent magnet 11A and a second permanent magnet 11B, which are axially magnetized, are provided on the outer peripheral surface of the rotary shaft 10 in the first to fourth portions made of iron or the like. It is fixed in the axial direction while being sandwiched by magnetic pole plates (core poles) 12A to 12D. As shown in the figure, the first and second permanent magnets 11A and 11B have the same magnetism S on the adjacent side and the magnetism N on the opposite side.

As shown in FIG. 1, the first to fourth magnetic pole plates 12A to 12D are provided with protrusions 14 extending in the radial direction at intervals of 90 degrees on the outer peripheral portion of a disk portion 13 that sandwiches a permanent magnet. An outer peripheral flange portion 15 is provided that is bent in the axial direction from the outer peripheral end of the projecting portion 14. The outer peripheral flange portion 15 has a shape in which the flange portions 15 of the first magnetic pole plate 12A and the fourth magnetic pole plate 12D in which the disk portion 13 is in contact with the same polarity N are bent inwardly close to each other, and the same polarity S is used. The flange portions 15 of the second magnetic pole plate 12B and the third magnetic pole plate 12C that are in contact with the disk portion 13 and that are in contact with the disk portion 13 are bent outwardly away from each other.

On the inner peripheral surface of each flange portion 15 facing the outer peripheral surfaces of the permanent magnets 11A and 11B with a gap C therebetween, an auxiliary permanent magnet formed of an arc-shaped thin width piece so as to cover the entire inner peripheral surface. 16 is fixed. These auxiliary permanent magnets 16 are set so that the flange fixing side (that is, the outer peripheral surface of the auxiliary permanent magnet 16) has the same polarity as the main magnetic flux flowing through the pole plate, and the inner peripheral surface side has the opposite polarity. There is. That is, the auxiliary permanent magnet 16 is magnetized in the circumferential direction, and the auxiliary permanent magnet 16A fixed to the inner peripheral surface of the flange portion 15 of the first magnetic pole plate 12A and the fourth magnetic pole plate 12D has the N pole on the outer peripheral surface side, The inner surface is the S pole. Further, the auxiliary permanent magnet 16B fixed to the inner peripheral surfaces of the flange portions of the second magnetic pole plate 12B and the third magnetic pole plate 12C has the S pole on the outer peripheral surface side and the N pole on the inner peripheral surface side.

A stator 21 is installed at a required interval on the outer periphery of a rotor 20 that integrally includes the rotary shaft 10, the permanent magnets 11A and 11B, the magnetic pole plates 12A to 12D, and the auxiliary permanent magnet 16. The winding wire 22 is housed in the recess 21 that is open to the inner peripheral surface, and the iron core 23 on the tip of the side wall of the recess 21 is arranged on the outer peripheral surface of the flange portion 15 at a predetermined interval.

In the rotating magnetic field type motor having the above structure, the main magnetic flux X flows from the permanent magnets 11 A and 11 B through the magnetic pole plates 12 A to 12 D to the iron core 23 as in the conventional example, and the rotation generated from the winding 22 is generated. The rotor 20 is rotated by the magnetic field.

In the above electric motor, the leakage flux generated in the gap C between the permanent magnets 11A, 11B and the flange portion 15 of the magnetic pole plates 12A to 12D is attached to the auxiliary permanent magnet 16 on the inner peripheral surface of the flange portion 15, Since the magnetic pole plate fixed side of the permanent magnet 16 has the same polarity as the magnetic flux flowing through the magnetic pole plate, the leakage magnetic flux can be significantly reduced. Therefore, it is possible to increase the main magnetic flux flowing in the iron 23 and realize high output.

3 and 4 show a second embodiment of the present invention, in which the auxiliary permanent magnet has a ring shape. That is, the ring-shaped auxiliary permanent magnet 30A is fixed to the inner peripheral surfaces of the flange portions 15 of the first magnetic pole plate 12A and the second magnetic pole plate 12B located on the peripheral surface in the same axial direction, and the third magnetic pole plate is also fixed. A ring-shaped auxiliary permanent magnetic pole 30B is fixed to the inner peripheral surfaces of the flange portion 15 of the fourth magnetic pole plate 12D and 12C.

The ring-shaped auxiliary permanent magnets 30A and 30B are magnetized by changing the polarity at intervals in the circumferential direction so as to have the same polarity as the polarity of the flange portion 15 to be fixed. That is, in the auxiliary permanent magnet 30A, the outer peripheral surface is the N pole at the fixing portion with the flange portion of the first magnetic pole plate 12A, and the outer peripheral surface is the S pole at the fixing portion with the flange portion of the second magnetic pole plate 12B. .

Further, the ring-shaped auxiliary permanent magnets 30A and 30B are fixed to the flange portion with a gap between adjacent surfaces.

In the second embodiment described above, since the auxiliary permanent magnet has a ring shape, the number of parts can be reduced and the mounting labor can be reduced, but it is necessary to change the polarity in the circumferential direction to magnetize.

[0022]

[Effect of the device]

 As apparent from the above description, in the present invention, the auxiliary permanent magnet is attached to the inner peripheral surface of the flange portion of the magnetic pole plate facing the permanent magnet with a gap, and the flange fixed side of the auxiliary permanent magnet is attached to the magnetic pole plate. Since it has the same polarity as the magnetic flux flowing through the magnetic flux, the magnetic flux leaking from the magnetic pole plate to the permanent magnetic pole can be reduced. Therefore, the magnetic flux flowing to the stator core can be increased, and the output of the electric motor can be increased. Further, since it is not necessary to widen the gap between the flange portion of the magnetic pole plate and the permanent magnet, the size of the electric motor can be reduced.

[Brief description of drawings]

FIG. 1 is a front view showing a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a front view showing a second embodiment of the present invention.

FIG. 4 is a sectional view taken along line IV-IV in FIG.

FIG. 5 is a cross-sectional view of a rotor including a conventional claw pole type magnetic pole plate.

FIG. 6 is a front view of a rotating field type electric motor including the rotor shown in FIG.

7 is a sectional view taken along line VII-VII of FIG.

[Explanation of symbols]

 10 rotating shaft 11A, 11B permanent magnet 12A-12D magnetic pole plate 13 disk part 15 flange part 16, 30A, 30B auxiliary permanent magnet

Front Page Continuation (72) Inventor Masahiro Takeda 390 Umeda, Kosai City, Shizuoka Prefecture Asmo Stock Company In-house (72) Inventor Kiyoshi Tamada 390 Umeda, Kosai City, Shizuoka Prefecture Asmo Stock Company In-house

Claims (1)

[Scope of utility model registration request] 1. A plurality of permanent magnets magnetized in the axial direction,
A rotating magnetic field type electric motor comprising: a rotor, which is sandwiched between magnetic pole plates having flange portions that are unevenly distributed in the rotational direction, and is fixed to a rotating shaft; and a stator which is arranged on the outer periphery of the rotor with a space therebetween. A thin auxiliary permanent magnet is fixed to the inner peripheral surface of the flange portion of the magnetic pole plate facing the outer peripheral surface of the magnet with a gap, and the polarity of the auxiliary permanent magnet is the same as the polarity flowing to the magnetic pole plate on the fixed side of the flange portion. A rotor of a rotating magnetic field type motor characterized by having a polarity.