JP2536882Y2 - Rotating electric machine - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotating electric machine, and more particularly to a rotating electric machine taking measures against cogging torque.

[0002]

2. Description of the Related Art Generally, a rotating electric machine such as a DC motor has an armature core provided with a salient pole portion and a groove for winding provided opposite to a field portion at a predetermined interval. Widely used. However, this type of DC motor
Due to the large difference in magnetic resistance between the salient pole portion and the winding groove, there is a problem that when the rotor is rotated, the magnetic flux pulsates and generates cogging torque. Had been taken.

FIG. 5 shows an example of such a conventional DC motor. This DC motor has a stator 10
0 and the rotor 200. And the stator 1
00 is provided with a ring-shaped magnet 10 functioning as a field portion.

[0004] The rotor 200 is configured to function as an armature, and specifically has a core 14 provided with a winding 12 rotatably disposed thereon.

The core 14 is formed by laminating a plurality of core sheets, and is formed between salient pole portions 16 facing the magnet 10 at a predetermined interval. It has a groove 18 for the winding 12.

[0006] Then, by supplying a current to the windings 12 of the core 14 in order, an electromagnetic interaction with the magnet 10 is generated so that a continuous rotation torque can be obtained.

However, in such an electric motor, the core sheets are simply laminated in the same direction to form the core 14, so that the salient pole portions 16 and the grooves between the salient pole portions 16 are formed. 18, the magnetic resistance pulsates due to the rotation of the core 14, and the output torque of the motor fluctuates due to the pulsation of the magnetic flux to generate cogging torque, thereby causing vibration and noise. there were.

Therefore, conventionally, by changing the shape of a core called a skew core as shown in FIG. 6, a change in magnetic resistance is eliminated, and occurrence of cogging torque is prevented. The skew core 20 is formed by laminating a plurality of core sheets 22 punched into the same shape one by one by rotating them at a constant angle in the same direction, and twisting the grooves 24 obliquely with respect to the axial direction. This suppresses the pulsation of the magnetic flux due to the rotation of the core 14.

[0009]

However, the conventional motor using such a skew core 20 has the following problems. In the motor using the skew core 20, the groove 24 is twisted obliquely with respect to the direction of the rotor rotation axis.
For this reason, there is a problem that the length of the groove 24 becomes longer and the winding becomes longer, and the output torque of the rotor decreases accordingly. If the groove 24 is twisted obliquely with respect to the direction of the rotation axis, the winding operation becomes extremely difficult when applying the winding, and particularly in the case of a small motor having a small core lamination thickness, the winding operation becomes extremely difficult. There was a problem. Furthermore, in the electric motor using the skew core 20, the core slot is oblique to the magnet, and it is necessary to rectify where the magnetic flux is large, so that the rectification state of the brush deteriorates and the brush life is shortened. There was also.

The present invention has been made in view of the above problems, and an object of the present invention is to suppress the generation of cogging torque by smoothing the change in the magnetic resistance between the salient pole portion of the core and the groove for winding. Moreover, the output torque is maintained by shortening the groove for the winding, the winding work is facilitated, and when a brush is used, the commutation state is improved so that the brush life can be improved. It is to provide an electric machine.

[0011]

To achieve the above object, a rotating electric machine according to the present invention is provided with a field part provided on one of a rotor side and a stator side and a field part provided on the other side of the rotor side or the stator side. And an armature, wherein the armature comprises:
A core having a salient pole portion and a groove for winding disposed opposite to the field portion at a predetermined interval, and a field portion facing surface of the salient pole portion is convex at a central portion with respect to the concave portion. It is characterized in that it is formed as an uneven step surface in which the area ratio of the part is large and the area ratio of the convex part to the concave part is small at both ends in the circumferential direction.

[0012]

The surface area of the salient pole portion facing the magnetic field has a large area ratio of the convex portion to the concave portion at the center portion and a small area ratio of the convex portion to the concave portion on both sides in the circumferential direction. The size of the winding groove, one side of the salient pole part in the circumferential direction, and the center of the salient pole part become smaller in order, and from the center of the salient pole part to the other side of the salient pole part, the groove for the winding And the magnetic resistance gradually changes.

Therefore, the magnetic resistance does not change abruptly during rotation of the rotor, so that the generation of cogging torque can be suppressed, and vibration and noise can be eliminated.

Further, in the present invention, since the winding groove of the armature core can be formed along the direction of the rotor rotation axis, the winding groove is shortened to maintain the output torque, and furthermore, The winding operation can be facilitated, and the rectification state of the brush can be improved to improve the life of the brush.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings.

[0016]First embodiment  1 and 2 show a DC motor according to an embodiment of the present invention.
It is shown.

This DC motor includes a stator 100 forming a field portion and a rotor 200 forming an armature.

In the stator 100, a plurality of arc-shaped magnets 30 constituting a field portion are arranged in an annular shape.

The rotor 200 includes an armature core 32. The armature core 32 is rotatably supported at predetermined intervals in the magnets 30 arranged in an annular shape. And this armature core 32 is a magnet 3
And a plurality of salient pole portions 34 facing the inner surface of the main body 0 at a predetermined interval, and a winding groove 36 formed between the salient pole portions 34. The winding 38 is applied to the base of each salient pole section 34 via the.

Surface 4 of salient pole portion 34 facing magnet 30
2, a convex portion 44 is formed so as to intersect the rotation axis direction. Thereby, the facing surface 40 is
It is formed as an uneven step surface provided with one convex portion 44 in an oblique direction, and the convex portion 4 with respect to the concave portion 46 is formed at the central portion 42.
4 is large, and the area ratio of the convex portion 44 to the concave portion 46 at both ends in the circumferential direction is small.

Accordingly, the resistance of the magnetic circuit formed between the magnet 30 and the core 32 is greatest at the groove 36, slightly reduced at both circumferential ends of the salient poles 34 adjacent thereto, and further reduced. The configuration can be such that it becomes smallest at the central part 42 of the pole part 34.

Further, in this embodiment, the steps at the both ends in the circumferential direction of the convex portion 44 are formed gently, and the magnetic resistance is also gradually changed from this surface.

In this embodiment, the configuration in which the magnetic resistance is gradually changed as described above prevents generation of cogging torque when the core 32 rotates, and eliminates generation of vibration and noise. Can be.

In forming the core 32,
The position of the protrusions 44 is slightly shifted from the end side, for example, five core sheets 50 are stacked, and the stacked core sheets 50 for each of the five sheets are inverted and combined to obtain the protrusions 44 having the above-described shape. Can be formed.

Further, since the groove 36 of the core 32 is formed in parallel with the direction of the rotation axis, it is possible to solve the problem as in the conventional skew core.

[0026]Second embodiment  FIG. 3 shows a second embodiment of the present invention. This embodiment
, The magnet facing surface 40 of the salient pole portion 34
The number of convex portions 44-1 and 44-2 are provided. The convex
The parts 44-1 and 44-2 are arranged adjacent to each other in the rotation axis direction,
In addition, in the central portion 42, the
It is formed by distributing it to the left and right positions. And the convex
The left or right adjacent portion of 44-1 and 44-2 is a concave portion 46.
It is formed.

As described above, also in this embodiment, the magnet facing surface 40 has a large area ratio of the convex portion 44 to the concave portion 46 at the central portion 42 and an area ratio of the convex portion 44 to the concave portion 46 at both ends in the circumferential direction. Is formed, the magnetic resistance of the core 32 becomes the same as in the first embodiment.
The portion of the groove 36 is the largest, and the salient pole portion 34
Slightly smaller at both ends in the circumferential direction of the
The configuration is such that it is the smallest at the portion.

As described above, by gradually changing the magnetic resistance, it is possible to prevent the occurrence of cogging torque during the rotation of the core 32, and to eliminate the occurrence of vibration and noise.

In this embodiment, the core 32
Is a plurality of sheets, for example, 10 sheets in this embodiment.
The core sheets 50 having the same shape and having the convex portions 44 are superimposed five by five, and the laminated core sheets 50 for each of the five sheets are inverted, combined, and laminated. By forming a single sheet, the convex portion 44 having the above-described shape can be easily formed.

In this embodiment, when the magnetic resistance of the core 32 is changed more gradually and continuously,
For example, as shown in FIG.
It is only necessary to arrange a plurality of convex portions 44-1, 44-2, 44-3 continuously so as to intersect with the direction of the rotation axis to form an uneven step surface.

It should be noted that the present invention is not limited to the above embodiment, and various implementations are possible within the scope of the present invention. For example, in the above-described embodiment, an electric motor has been described as an example, but the present invention is not limited to this, and can be applied to, for example, a generator.

Further, in each of the embodiments described above, the case where the convex portions 44 extending in the oblique direction are formed in a row on the magnet facing surface 40 has been described as an example. However, the present invention is not limited to this, and the present invention is not limited thereto. The portions 44 are provided in a plurality of rows in parallel as necessary, so that the change in magnetoresistance can be made more gradual.

In the above embodiment, the case where the armature is provided on the rotor side and the field portion is provided on the stator side has been described as an example. However, the present invention is not limited to this, and the armature may be provided with a stator if necessary. And the field portion may be provided on the rotor side.

[0034]

As described above, according to the rotating electric machine of the present invention, the area of the salient pole portion facing the magnetic field portion has a large area ratio of the convex portion to the concave portion at the center portion, and the concave portions at both ends in the circumferential direction. Is formed as a concave-convex step surface in which the area ratio of the convex portion to the convex portion is small, so that the magnitude of the magnetic resistance of the core is the same as the winding groove, one side in the circumferential direction of the salient pole portion, It becomes smaller in order, and further increases sequentially from the center of the salient pole part to the other side of the salient pole part, the groove for winding, so when the rotor is rotated,
This has the effect of gradually changing the magnetic resistance of the core, suppressing the occurrence of cogging torque, and eliminating vibration and noise.

Further, since the winding groove for the core can be formed along the axial direction, the winding groove can be shortened to maintain the output torque and facilitate the winding operation. Can,
There is also an effect that the rectification state of the brush can be improved and the life of the brush can be improved.

[Brief description of the drawings]

FIG. 1 is an enlarged sectional view showing a main part of an electric motor according to an embodiment of the present invention.

FIG. 2 is an enlarged perspective view showing a salient pole portion of the core of FIG. 1;

FIG. 3 is a perspective view corresponding to FIG. 2 showing another embodiment of the present invention.

FIG. 4 is a perspective view showing a modified example of the salient pole portion of the core shown in FIG.

FIG. 5 is a sectional view showing a conventional electric motor.

FIG. 6 is a side view showing a state of a conventional skew core.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 30 Magnet 32 Core 34 Salient pole part 36 Groove 38 Winding 40 Opposing surface 42 Central part 44 Convex part
AS009902

Claims (2)

(57) [Scope of request for utility model registration] A field part provided on one of a rotor side and a stator side; and an armature provided on the other side of the rotor side or the stator side, wherein the armature is provided with respect to the field part. A core having a salient pole portion and a groove for winding disposed opposite to each other at a predetermined interval; and a field portion facing surface of the salient pole portion has a large area ratio of a convex portion to a concave portion at a central portion. A rotating electric machine characterized in that the rotating electric machine is formed as an uneven step surface in which the area ratio of the convex portion to the concave portion is small at both ends in the circumferential direction. 2. The device according to claim 1, wherein the field portion is formed as a ring-shaped magnet provided on a stator side, and the core of the armature is provided on a rotor side at a predetermined distance from the magnet. A rotating electrical machine comprising a salient pole portion and a groove for winding, which are opposed to each other.