JPWO2007083724A1 - Gap winding type motor - Google Patents

Abstract

The purpose of the present invention is to provide a gap winding motor that has a rotor structure that is capable of increasing the volume and halving the number of permanent magnets, reducing costs, shortening the bonding time, and having excellent workability and reliability. To do. A stator having an armature winding formed by winding a plurality of air-core-shaped coils (3) for forming a rotating magnetic field on the inner peripheral surface of a cylindrical stator core (2), and the stator and magnetism Provided with a permanent magnet (4) which is provided on a rotor core (9) arranged concentrically through a static gap, has a plurality of magnetic poles with different polarities alternately, and is divided into arcs In a gap winding type motor composed of a child and a single unit of a plurality of divided permanent magnets (4), an N-pole magnetized portion (5) and an S-pole magnetized with N-pole and S-pole two-pole magnetization. A non-magnetized part (8) for suppressing cogging is provided between the N pole magnetized part (5) and the S pole magnetized part (6).

Description

  The present invention relates to a brushless DC motor used as a drive motor in an industrial field such as FA or OA or a drive motor of an electric vehicle, and in particular, forms a rotating magnetic field in an annular stator core without magnetic salient poles (slots). TECHNICAL FIELD The present invention relates to a smooth armature winding type motor that is equipped with an armature winding for a so-called gap winding type motor.

Conventionally, a brushless DC motor used as a drive motor in an industrial field such as FA or OA, or in recent years as a drive motor for an electric vehicle, having a rotating magnetic field on an annular stator core without magnetic salient poles (slots). A smooth armature winding type motor having an armature winding formed by winding a plurality of forming air-core coils, a so-called gap winding type motor, is as shown in FIGS. 3 is a front sectional view of a conventional gap winding motor, and FIG. 4 is an enlarged front sectional view of an electromagnetic part of the gap winding motor of FIG.
In the drawing, 1 is a frame, 2 is a stator core, 3 is an air-core coil, 4 is a permanent magnet, 5 is a north pole of the permanent magnet, 6 is a south pole of the permanent magnet, 7 is a gap between the permanent magnets, 9 Is a rotor core, 10 is a shaft, and 11 is a magnetic air gap.
The stator of the gap winding motor includes a stator core 2 formed in a cylindrical shape by laminating silicon steel plates, and a thin insulating layer provided on the inner peripheral surface of the stator core 2 to ensure a required withstand voltage. The armature winding is formed by winding a plurality of air-core-shaped coils 3 for forming a rotating magnetic field, which are wound in a concentrated manner via a wire, at equal intervals. The armature winding is molded or impregnated with resin and is fixed integrally with the stator core 2.
Further, the rotor is disposed concentrically with the stator and the magnetic gap 11 and is fitted to the outer peripheral surface of the shaft 10 and fixed to the rotor core 9. And a plurality of magnetic poles having different polarities alternately, and composed of, for example, a rare earth permanent magnet 4 divided in an arc shape,
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The rotor is rotatably supported via a bearing (not shown) between the rotor and the stator.
Here, the N-pole 5 and S-pole 6 magnets constituting the permanent magnet 4 are bonded and fixed to the outer periphery of the rotor core 9 at regular intervals with a fixed gap 7 by a jig or the like. The number of permanent magnets is determined by the basic slot combination. In general, when it is desired to minimize the volume of the electromagnetic part, the number of permanent magnets is large. (For example, refer to Patent Documents 1 and 2).
Japanese Patent Laid-Open No. 2002-159152 (Specification, page 3, FIG. 1) Japanese Patent Laid-Open No. 2002-191146 (Specification, page 2, FIG. 1)

In the conventional gap winding motor, the number of permanent magnets further increases because the number of magnetic poles required increases as the outer diameter increases. If the number of permanent magnets is increased and subdivided, the volume of the permanent magnet itself becomes smaller, but generally the small volume of the magnet alone causes an increase in cost, and the mounting work when positioning and bonding the magnet to the rotor or The inspection after installing the magnet required a lot of time, and the productivity was poor. Further, when the number of magnets increases, it is easy to pick up the influence of the shape error of the magnet alone, the magnet mounting error, etc., and there is a problem related to reliability.
The present invention has been made in view of such problems, and can increase the volume and quantity of permanent magnets, reduce the cost, shorten the bonding time, and improve workability and reliability. An object of the present invention is to provide a gap winding motor having an excellent rotor structure.

In order to solve the above problems, the present invention is configured as follows.
According to a first aspect of the present invention, there is provided an electric machine in which a cylindrical stator core and a plurality of air-core-shaped coils for forming a rotating magnetic field are wound around either the inner peripheral surface or the outer peripheral surface of the stator core. A stator composed of a rotor winding, a rotor core disposed concentrically with the stator and a magnetic gap, and a plurality of magnetic poles provided on the rotor core and having different polarities alternately. In addition, in the gap winding type motor provided with a rotor composed of a permanent magnet divided in an arc shape, the single piece of the plurality of divided permanent magnets is attached in two poles of N pole and S pole. It is characterized by having a magnetized N-pole magnetized part and S-pole magnetized part.
The invention according to claim 2 is the gap winding type motor according to claim 1, wherein a non-magnetized portion for suppressing cogging is provided between the N-pole magnetized portion and the S-pole magnetized portion. It is characterized by being.

According to the first aspect of the present invention, since the number of permanent magnets can be halved, the time required for attaching the permanent magnets to the rotor core or the inspection after attaching the magnets can be reduced, and the productivity is improved. . In addition, since the number of magnets is halved, the shape error of the magnet alone, the magnet mounting error, and the like are suppressed, so that the reliability is improved. Moreover, since the adhesion area per permanent magnet increases, the adhesion strength increases and the reliability improves. Furthermore, since the weight per permanent magnet increases, the cost can be reduced.
According to the second aspect of the invention, the balance between the N pole and the S pole by the permanent magnet becomes uniform at an arbitrary position, and the cogging torque can be suppressed.

Front sectional view of a gap winding motor showing a first embodiment of the present invention Fig. 1 is an enlarged front sectional view of the electromagnetic part of the gap winding motor of Fig. 1. Front sectional view of a conventional gap winding motor Fig. 3 is an enlarged front sectional view of the electromagnetic part of the gap winding motor of Fig. 3.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Frame 2 Stator core 3 Air core-shaped coil 4 Permanent magnet 5 N pole magnetized part 6 S pole magnetized part 7 Permanent magnet gap 8 Non-magnetized part 9 Rotor core 10 Shaft 11 Magnetic air gap part

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a front sectional view of a gap winding motor showing a first embodiment of the present invention, and FIG. 2 is an enlarged front sectional view of an electromagnetic part of the gap winding motor of FIG. In this embodiment, an example of an inner rotor type gap winding motor having 20 poles and 15 coils is shown. Note that the description of the same constituent elements of the present invention as those of the prior art is omitted, and only different points will be described.

The present invention is different from the prior art as follows.
That is, the single unit of the plurality of divided permanent magnets 4 is provided with N-pole and S-pole two-pole magnetization, and has an N-pole magnetized portion 5 and an S-pole magnetized portion 6. This is that a non-magnetized part 8 for suppressing cogging is provided between the magnetic part 5 and the S pole magnetized part 6.

Next, assembly of the magnet will be described.
In this embodiment (FIGS. 1 and 2), an example of an inner rotor type gap winding motor having 20 poles in the field and 15 coils in the armature is shown, and the slot combination is the same as the prior art. There is no change, and the permanent magnet 4 of this embodiment has a total of 10 divided magnets, and 1 divided magnet corresponds to 2 poles, and only the size and quantity of the permanent magnets change compared to the conventional technology. is doing.
The rotor, after machining the shaft 10, cleans the surface and fits the rotor core 9 formed of laminated steel plates on the shaft, and then applies an adhesive (not shown) to the rotor core 9. Then, the plurality of divided permanent magnets 4 are fixed on the rotor. Magnetization of the magnet may be either a method in which a divided magnet magnetized before bonding is directly bonded to the shaft, or a method in which an unmagnetized divided magnet is bonded to the shaft and then magnetized. In this case, the rotor is a surface magnet type rotor, and is not attached between the N-pole magnetized portion 5 and the S-pole magnetized portion 6 of the one-part magnet constituting the permanent magnet so that the cogging torque is minimized. Although the magnetic part 8 is provided so that an appropriate interval can be obtained, a skew is provided by shifting the plurality of divided permanent magnets 4 in the circumferential direction along the axial direction of the rotor for other cogging torque countermeasures. You may comprise.
In addition, in a surface magnet type rotor, when receiving a large centrifugal force like a motor for high speed rotation, as a fixing method for obtaining strength, a thin-walled outer periphery of a permanent magnet arranged and fixed on the rotor surface is used. The ring member may be press-fitted and fixed, or may be fixed by a wedge between permanent magnet gaps arranged at equal intervals. Recently, thin-walled ring members include materials with high tensile strength, such as carbon fiber reinforced plastic (CFRP) and titanium. If these can be molded into a ring shape and press-fitted onto the rotor surface, the rotation speed will be greater. Can be obtained, and the characteristics of the motor can be improved and the manufacture can be facilitated.

  The gap winding motor of the present invention is capable of increasing the volume and halving the number of permanent magnets, reducing the cost, shortening the bonding time, and having a rotor structure with excellent workability and reliability. The present invention can be applied to a brushless DC motor used as a drive motor in an industrial field such as FA or OA or a drive motor of an electric vehicle.

Claims (2)

A stator composed of a stator core and an armature winding formed by winding a plurality of air-core-shaped coils for forming a rotating magnetic field around either the inner peripheral surface or the outer peripheral surface of the stator core;
A permanent magnet that is concentrically arranged with the stator and a magnetic gap between the stator and a plurality of magnetic poles that are provided on the rotor core and have different polarities alternately, and is divided into arcs A rotor composed of
In the gap winding type motor with
The gap winding type motor according to claim 1, wherein each of the plurality of divided permanent magnets has an N-pole magnetized portion and an S-pole magnetized portion subjected to N-pole and S-pole magnetization.   2. The gap winding motor according to claim 1, wherein a non-magnetized portion for suppressing cogging is provided between the N-pole magnetized portion and the S-pole magnetized portion.

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