JP2001054270A - Counterposed type motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a counterposed type motor for reducing eddy current loss in a magnetic pole piece and for saving power. SOLUTION: A projecting part 21 that becomes the core of a stator yoke 13 or a magnetic pole piece 15 that is mounted to the core of a rotor part are divided into a plurality of semi-magnetic-pole pieces 15a and 15b for each pole in an example, while opposing the magnet of a rotor or stator part. Also, instead of division, a cutout, a through-hole, a bend, or the like may be adopted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a pole piece mounted on a core of a starter section or a rotor section in a surface facing motor in which a stator section and a rotor section are arranged so as to overlap on the same axis.

[0002]

2. Description of the Related Art FIG. 6 is a diagram showing a cross-sectional structure of a surface-facing motor disclosed in Japanese Patent Application Laid-Open No. 62-95953.
In the figure, the surface facing type motor is divided into a stator part A and a rotor part B. In the stator section A, a winding coil 53 is wound around a core 52 formed on a stator yoke 51. The stator yoke 51 is fixed to the housing 54, and the end face of the core 52 is a pole piece 55. Rotor part B
Then, the magnet 57 is fixed to the rotor yoke 56. The rotor yoke 56 is fixed to a shaft 58, and the shaft 58 is held by the housing 54 via bearings 59, 60.

In the surface facing type motor having such a structure, the core 52 is protruded into the winding coil 53 and the magnet 57
By reducing the distance (gap) between them, the magnetic flux collection efficiency is increased and a high torque can be obtained.
In order to further increase the torque, a core 52 having a core with a flange is also known (Japanese Patent Laid-Open No. 62-25 / 1987).
858).

[0004] Such a core 52 and a stator yoke 51
By using pressed parts for the integration of the core 52, the integration of the core 52 and the pole piece 55, and the core with a flange, the cost can be reduced.

[0005]

By the way, in a conventional motor having a circumferentially opposed core, iron cores are laminated to reduce power consumption by reducing eddy current loss. On the other hand, in the face-to-face type motor, a pole piece having a large area may be formed on the face of the rotor section facing the magnet in order to increase the magnetic flux collection efficiency. However, this pole piece is easily affected by eddy current loss. , Which hinders power saving.

An object of the present invention is to provide a surface-facing motor that can reduce eddy current loss in a pole piece and save power.

[0007]

In order to achieve the above object, according to the first aspect of the present invention, a magnetic pole piece attached to a stator portion or a core of a rotor portion facing a magnet of the rotor portion or the stator portion is provided. Divide into multiples for each pole. This can reduce the eddy current generated in the direction perpendicular to the magnetic flux that changes in the pole piece. The direction of division may be a circumferential direction, a radial direction, or any other direction, and the number of divisions may be divided into two for each pole or three.
It may be divided into two or more.

According to the second aspect of the present invention, the pole piece attached to the core of the stator or the rotor portion facing the magnet of the rotor or the stator portion has a cutting portion extending from the outer periphery to the inside for each pole. Provide a notch. This can reduce the eddy current generated in the direction perpendicular to the magnetic flux that changes in the pole piece.

Further, according to the present invention, a through hole is provided for each pole in a pole piece attached to the stator or the core of the rotor facing the magnet of the rotor or the stator. This can reduce the eddy current generated in the direction perpendicular to the magnetic flux that changes in the pole piece.

The notch and the through hole may be formed at the same time. Further, at least one of a notch or a through hole may be formed in each of the plurality of divided magnetic pole pieces.

Further, in the invention according to claim 4, the magnetic pole piece attached to the hollow core of the stator portion or the rotor portion facing the magnet of the rotor portion or the stator portion has the two-folded portion bent for each pole. Fit into the hollow core and fix. This can reduce the eddy current generated in the direction perpendicular to the magnetic flux that changes in the pole piece.

[0012]

Embodiments of the present invention will be described below. The face-to-face type motor according to the present invention is obtained by improving the shape of the pole piece attached to the core.
1, the winding coil 53 and the pole piece 55) are mainly shown. Also,
The present embodiment will be described using an example in which a stator yoke and a core are integrally formed.

FIG. 1 is an exploded view showing a main part of a first embodiment of a surface-facing motor according to the present invention. The part shown in the lower part of FIG. 1 shows the stator yoke 13 in which the convex portion 21 serving as a core is formed by press bending. The components shown in the center of FIG. 1 show a bobbin 22 mounted on the projection 21 of the stator yoke 13 and the winding coil 12 wound around the bobbin 22. The part shown in the upper part of FIG. 1 shows the pole piece 15 fixed to the projection 21 of the stator yoke 13 on which the winding coil 12 is mounted. The stator yoke 13 is formed by bending a metal annular ring having the same diameter and width, and includes a convex portion 21 and a central hole 2 of a bobbin 22.
It has a side portion 13a that supports the convex portion 21 that enters the 2a, and a support portion 13b on which the bobbin 22 is placed.

The magnetic pole piece 15 collects magnetic flux in opposition to a magnet of a rotor section (not shown), and has a configuration in which one pole is divided into two parts in an angular direction (circumferential direction). That is, the pole piece 15 is a set of two pieces for each pole, and the half pole piece 1 divided into two pieces in one projection 21.
5a and 15b are fixed such that the divided space 15c is located at the center of the convex portion 21. In addition, two half-pole pieces 15a and 15b and a protrusion 2 of the stator yoke 13 are provided for each pole.
1 is fixed by screwing, welding, bonding or the like.

By dividing the magnetic pole piece 15 into a plurality of parts for each pole, an eddy current generated on a plane perpendicular to the direction of the changing magnetic flux generated by the magnet of the rotating rotor portion is divided by the divided space 15c. The eddy current has a small shape, and the total eddy current loss is reduced. In addition,
The generation of the eddy current loss is caused by the separation space 1 that separates each pole piece 15.
It is also prevented by the presence of 5d. As the magnetic pole piece 15 having such a function, a configuration in which a notch, a through hole, or the like is provided may be used in addition to the configuration in which the magnetic pole piece 15 is divided into a plurality in the circumferential direction. An example is shown in FIG.

FIG. 2A shows a single pole piece 15 corresponding to one projection 21, in which a notch 23 extending from the outer periphery of the pole piece 15 to the inside is formed. The position and direction of the notch 23 are not particularly limited, and may be other than those shown in the drawings. FIG. 2B also shows a single pole piece 15.
And a plurality of notches 23 and through holes 24 are provided in the pole piece 15.
FIG. 2C shows the magnetic pole piece 15 divided into a plurality in the radial direction. Circumferential division, radial division,
Notches and through holes can be used in any combination.

FIG. 3 shows an example in which the stator of the first embodiment is applied to a motor.

The motor 11 has a stator portion A and a rotor portion B
It is mainly composed of The stator portion A includes a stator yoke 13 and a winding coil 12 arranged around the protrusion 21.
, Bobbin 22, pole piece 15, stator yoke 13
Are mounted on the base plate 16, a bearing holder 17, and a bearing 18 for bearing the rotation of the rotor unit 13. The rotor portion B includes a rotor yoke 31 serving as a back yoke made of a magnetic material, a donut-shaped magnet 32, a shaft 33, and a connecting portion 34 for connecting the shaft 27 and the rotor yoke 25.

The motor 11 has a high magnetizing force due to the convex portions 21 of the stator yoke 13 and has a high driving force. In addition, since the pole piece 15 is divided in the circumferential direction or the radial direction, or is provided with a notch or a through hole, eddy current loss is reduced. Further, since the stator yoke 13 is formed by press-molding one metal material, the manufacture is easy.

FIG. 4 is an exploded view of a main part of a second embodiment of the surface-facing motor according to the present invention. The lower part of FIG. 4 shows the stator yoke 13 in which the standing portion 25 serving as a core is formed by punching and bending. The two standing portions 25 are formed in parallel for each pole. Above the stator yoke 13, a standing portion 25 of the stator yoke 13 is provided.
1 shows a winding coil 12 wound around a bobbin 22 mounted on the bobbin. 4 shows the pole piece 15 fixed to the upright portion 25 of the stator yoke 13 on which the winding coil 12 is mounted.

The magnetic pole piece 15 has a two-folded portion 26 bent from the center, and the two-folded portion 26 is fitted and fixed between two upright portions 25. That is, the distance between the two upright portions 25 formed in parallel is
(Double the thickness of the pole piece 15), and is set so that it can be fixed only by press-fitting the pole piece 15, for example.

The magnet 32 has a donut shape and is multipolar magnetized alternately in the NS in the radial direction, and is fixed inside the rotor yoke 31. The rotor unit including the magnet 32 and the rotor yoke 31 has the same configuration as the rotor unit 13 of the motor to which the configuration of the first embodiment is applied.

FIG. 5 shows a state in which the winding coil 12 and the pole piece 15 are mounted on the stator yoke 13. FIG. 5 (A)
5B is a plan view, FIG. 5B is a front view, and FIG.
(C) shows the pole piece 15 on the standing portion 25 of the stator yoke 13.
FIG. 7 is a partial cross-sectional view showing a state in which the two-fold part 26 is fitted. Thus, the eddy current generated in the pole piece 15 can be significantly reduced only by forming the folded portion 26 on the pole piece 15. Further, by forming an insulating film on the contact surface 27 of the two-fold part 26 or inserting an insulator, the pole piece 15 can be substantially divided into two.

The bobbin 22 is connected to the stator yoke 13
The bobbin 22 is placed on the stator yoke 13 by abutting the flange portion of the bobbin 22 on the center side portion and the outer peripheral side portion. Also,
The width of the pole piece 15 in the circumferential direction on the center side is substantially the same as the width of the bobbin 22, and the width on the outer peripheral side is larger than the width of the bobbin 22 as shown in FIG. The width of the hole 13c is larger than the width of the hole 13c after the formation of the portion 25, and the size is such that the hole 13c is completely covered after the formation. In addition, the notch or the through-hole shown in the first embodiment may be provided in the pole piece 15 on the surface of the rotor portion facing the magnet, in addition to the folded portion 26.

Although each of the above embodiments is an example of a preferred embodiment of the present invention, the present invention is not limited to this, and various modifications may be made without departing from the spirit of the present invention. It is possible. For example, the projection 21 serving as a core for fixing the pole piece 15 is an integrally formed part obtained by press-bending the stator yoke 13 in the above description, but a separate core may be attached to the stator yoke 13. Further, in each embodiment, all the pole pieces are divided or notches or through holes are provided in all the pole pieces, but only some of the pole pieces are divided or some of the pole pieces are divided. Notches or through holes may be provided only on one piece.

The motor of the present invention is a motor in which the rotational force is increased while maintaining the goodness of the surface-facing motor, and is suitable for application to a brushless motor for a pump. Further, the present invention may be applied to a brushless motor other than a pump, or may be applied to a kind of brushless motor, such as a stepping motor. In addition, a magnet is installed in the stator section instead of the rotor section, and the pole piece 15 is provided in the rotor section.
Can also be applied to a motor provided with.

[0027]

As described above, in the surface facing type motor according to the first aspect of the present invention, by dividing the pole piece, the changing magnetic flux and the eddy current generated on the plane perpendicular to the direction are reduced.
Power saving can be achieved.

Further, the surface facing type motor according to claim 2 is
By forming the notch in the outer peripheral portion of the pole piece, eddy current can be similarly reduced and power can be saved. Further, in the surface-facing motor according to the third aspect, by providing a through hole in the pole piece, eddy current can be similarly reduced and power can be saved.

By appropriately combining the division of the pole piece, the notch formed in the outer peripheral portion, and the through hole,
Further, eddy current can be reduced, and power can be saved.

The surface facing motor according to claim 4 is
By providing the magnetic pole piece with a folded part and fitting it into the hollow core and fixing it, the eddy current can be similarly reduced and power can be saved. In addition, press-fitting can be employed for fixing, which facilitates assembly.

[Brief description of the drawings]

FIG. 1 is an exploded configuration diagram showing a stator section in a first embodiment of a surface-facing motor according to the present invention.

FIG. 2 is a diagram showing another configuration example of the pole piece in the first embodiment of FIG. 1;

FIG. 3 is a cross-sectional view showing an overall configuration of a surface-facing motor using the stator shown in FIG.

FIG. 4 is an exploded configuration diagram showing a stator section and its periphery in a second embodiment of the surface-facing motor according to the present invention.

5A and 5B are diagrams showing a state in which a winding coil and a pole piece are mounted on a stator yoke according to the second embodiment of FIG. 4, wherein FIG. 5A is a plan view, FIG. 5B is a front view, and FIG. () Is a partial sectional view around the pole piece.

FIG. 6 is a diagram showing a cross-sectional configuration of a conventional surface-facing motor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 12 Winding coil 13 Stator yoke 15 Magnetic pole piece 21 Convex part (core) 22 Bobbin 23 Notch 24 Through hole 25 Standing part 26 Folded part 31 Rotor yoke 32 Magnet A Stator part B Rotor part

Continuation of the front page F term (reference) 5H019 AA04 CC02 DD01 EE01 5H621 GA02 GA12 GB03 GB10 HH05 JK05 JK18 JK19 5H622 CA01 CA05 CB05 PP03 PP19

Claims (4)

[Claims] 1. A surface-facing motor in which a stator portion and a rotor portion are arranged so as to overlap on the same axis, wherein a magnetic pole attached to the core of the stator portion or the rotor portion facing the rotor portion or the magnet of the stator portion. The surface-facing motor is characterized in that the piece is divided into a plurality of parts for each pole. 2. A surface-facing motor in which a stator portion and a rotor portion are arranged so as to overlap on the same axis, wherein a magnetic pole attached to the stator portion or a core of the rotor portion facing the rotor portion or a magnet of the stator portion. The surface-facing motor is characterized in that the piece has a notch extending from the outer periphery to the inside for each pole. 3. A surface-facing motor in which a stator portion and a rotor portion are arranged so as to overlap on the same axis, wherein a magnetic pole attached to the stator portion or the core of the rotor portion so as to face the rotor portion or the magnet of the stator portion. A surface-facing type motor, wherein each piece has a through hole for each pole. 4. A surface-facing motor in which a stator portion and a rotor portion are disposed so as to overlap on the same axis, wherein the motor is attached to the stator portion or the hollow core of the rotor portion so as to face the rotor portion or the magnet of the stator portion. A surface-facing motor, wherein the magnetic pole piece has a configuration in which a folded portion that is bent for each pole is fitted into the hollow core.