JP2001333555A - Slot-less radial gap motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a slotless radial gap motor capable of preventing iron loss and torque ripples for increasing efficiency. SOLUTION: This motor comprises a stator (1), consisting of a cylindrical stator core (11), windings (41, 42, 43) of a plurality of phases mounted on the inner-periphery side of the stator core (11), a retaining member (61) retaining the windings (41, 42, 43) on the inner periphery of the stator core (11), and a rotor (2) which is disposed at a hollow section of the stator (1), and formed by affixing a plurality of permanent magnets (22) on the stator (1) side of a rotor core (21) rotatably, in the presence of the retaining member (61) and a prescribed gap.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slotless radial gap motor using a permanent magnet for a rotor.

[0002]

2. Description of the Related Art FIG. 3 is a perspective view showing the structure of a conventional radial gap type motor. This radial gap type motor includes a stator 1, a rotor 2, and a rotating shaft 3.

The stator 1 has a cylindrical stator core 11.
Has a structure in which a plurality of columnar tooth portions 12 are provided on the inner peripheral surface of the. The plurality of teeth 12 are provided at equal intervals in the circumferential direction of the stator core 11, whereby slots (grooves) 13 are formed between adjacent teeth 12.

[0004] Since the longitudinal direction of each tooth portion 12 is the axial direction of the stator core 11, the shape of each slot 13 is also a column shape whose longitudinal direction is the axial direction of the stator core 11. Further, since the cross-sectional shape of each tooth portion 12 is wide at the distal end, the cross-sectional shape of each slot 13 is a semi-closed slot with a narrowed distal end. Since 12 teeth 12 are provided, slots (grooves) 13 are provided.
Are also 12. In these slots 13,
A coil (winding) 4 is wound as described later.

The stator core 11 has a laminated structure of magnetic steel sheets. That is, the stator core 11 has a structure in which a plurality of thin electromagnetic steel sheets 14 having a plurality of teeth and forming a hollow disk shape are laminated in the axial direction of the rotating shaft 3 and are welded at a plurality of locations on the side. .

The rotor 2 has a cylindrical rotor core 21.
Is formed by adhering four permanent magnets 22 each having a columnar shape having a fan-shaped cross section on the peripheral side surface of each of the permanent magnets.
The poles and S poles are alternately arranged and magnetized. Rotor 2
Are inserted into the hollow portion of the stator 1 so as to have a gap 5 of, for example, about 1 mm with each tooth portion 12 of the stator 1. The rotating shaft 3 is fitted into the hollow portion of the rotor core 11.

With such a structure, the rotor 2 can rotate with respect to the stator 1 with the gap 5 remaining.
For example, a fan or the like for an air conditioner is attached to the tip of the rotating shaft 3.

FIG. 4A is a cross-sectional view of the radial gap type motor, and FIG. 4B is a diagram showing an arrangement relation and connection state of each coil. 4, the same parts as those in FIG. 3 are denoted by the same reference numerals. One of a U-phase coil 41, a V-phase coil 42, and a W-phase coil 43 is inserted into and wound around each slot 13 formed by each tooth portion 12 of the stator 1.

As shown in FIGS. 4A and 4B, each of the coils 41, 42 and 43 is wound around two corresponding slots 13, and the two slots are three slots. Minutes away. And
These coils 41, 42, 43 are wound in two stages in the radial direction of the stator 1 such that the upper and lower coils are not in electrical contact with each other. In this case, in both the upper and lower stages, in the circumferential direction of the stator core 11, the U-phase coil 41,
The V-phase coil 42 and the W-phase coil 43 are wound in this order.

In the radial gap type motor having the above-described configuration, a magnetic field is generated by passing a current through each of the coils 41, 42, 43 of the stator 1, and the magnetic flux is fixed to the respective teeth 12 of the stator 1. Pass through the child iron core 11. A torque is generated by magnetic attraction and repulsion between the stator 1 and each of the permanent magnets 22 with this, and the rotor 2 rotates together with the rotating shaft 3.

[0011]

In the conventional radial gap type motor having the above-described structure, an eddy current loss is generated in the tooth portion, so that there is a problem that iron loss occurs and efficiency is deteriorated. In addition, since the slot is provided, there is a problem that torque ripple increases.

It is an object of the present invention to provide a slotless radial gap type motor that prevents iron loss and torque ripple and improves efficiency.

[0013]

SUMMARY OF THE INVENTION In order to solve the above problems and achieve the object, a slotless radial gap motor according to the present invention is configured as follows.

(1) A slotless radial gap type motor according to the present invention comprises: a stator having a cylindrical stator core; a plurality of phase windings provided on an inner peripheral side of the stator core; A holding member for holding a winding on the inner peripheral surface of the stator core, and disposed in a hollow portion of the stator,
A plurality of permanent magnets are attached to the stator side of the rotor core, and the rotor is configured to include the holding member and a rotor rotatable with a predetermined gap.

(2) A slotless radial gap motor according to the present invention is the motor described in (1) above, and the holding member is made of a molding material.

(3) A slotless radial gap motor according to the present invention is the motor described in (1) or (2) above, and magnetic powder is mixed in the holding member.

[0017]

FIG. 1 is a perspective view showing a structure of a slotless radial gap type motor according to an embodiment of the present invention. In FIG. 1, the same parts as those in FIG. 3 are denoted by the same reference numerals. The slotless radial gap motor includes a stator 1, a rotor 2, and a rotating shaft 3.

The stator 1 has a cylindrical stator core 11.
And the stator core 11 has a laminated structure of electromagnetic steel sheets. That is, the stator core 11 has a structure in which a plurality of thin electromagnetic steel plates 14 having a hollow disk shape are laminated in the axial direction of the rotating shaft 3 and are welded at a plurality of locations on the side. On an inner peripheral surface of the stator core 11, a cylindrical molded winding 6 described later is provided.

The rotor 2 has a rotor core 21 having a cylindrical shape.
Is formed by adhering four permanent magnets 22 each having a columnar shape having a fan-shaped cross section on the peripheral side surface of each of the permanent magnets.
The poles and S poles are alternately arranged and magnetized. Rotor 2
Are inserted into the hollow portion of the stator 1 so as to have a gap 5 of, for example, about 1 mm from the mold winding 6. The rotating shaft 3 is fitted into the hollow portion of the rotor core 21.

With such a structure, the rotor 2 can rotate with the gap 5 existing with respect to the mold winding 6. For example, a fan or the like for an air conditioner is attached to the tip of the rotating shaft 3.

FIG. 2 is a cross-sectional view of the slotless radial gap type motor. In FIG. 2, the same parts as those in FIG. 4 are denoted by the same reference numerals. In the mold winding 6,
Coil (winding) wound around the slot shown in FIG.
A plurality of coils 41, 42, 43 wound in a ring shape in advance so as to have the same shape as the above are held by a molding material 61.

The arrangement relationship and connection state of the coils 41, 42, 43 are the same as those shown in FIGS. These coils 41, 42, 43 are held in two stages vertically in the radial direction of the stator 1, and the upper and lower coils are held so as not to be in electrical contact with each other. In this case, the U-phase coil 41, the V-phase coil 42, and the W-phase coil 43 are held in the circumferential direction of the stator core 11 in both the upper and lower stages in this order.

Each coil 41, 4 in the molded winding 6
A stranded copper wire (Litz wire) formed by a thin wire is used for the 2,43 conductive wires. The molding material 61 is a casting resin (resin). As an example of this resin,
It is a heat-curable epoxy casting resin filled with a filler, and has a curing temperature of 75 to 80C / 2 to 3H + 105C / 2.
３3H, and an insulation type of F type can be used. Further, magnetic powder (not shown) such as iron powder, nickel powder, amorphous, and ferrite is mixed in the molding material 61.

In the slotless radial gap type motor having the above-described structure, a magnetic field is generated by applying a current to each of the coils 41, 42, and 43 of the molded winding 6, and the magnetic flux is generated by the molded winding 6 and the stator. 1 stator core 11
Pass through. A torque is generated by a magnetic attraction force and a repulsion force between the stator core 11 and each of the permanent magnets 22 accompanying this, and the rotor 2 rotates together with the rotating shaft 3.

According to the present embodiment, since the stator is not provided with the teeth for winding the coil as in the related art, but is formed as a molded winding, the iron loss caused by the teeth can be eliminated. With this configuration, the magnetic flux passes through the molded winding evenly, but eddy current loss in the conductor can be eliminated because the wire is used as the conductor of the coil. Thus, eliminating the conventionally formed slots eliminates torque ripple and eliminates iron loss caused by the teeth, thereby increasing the efficiency of the motor. Also, it is considered that the provision of the mold winding increases the electromagnetic gap between the stator core 11 and each of the permanent magnets 22 and makes it difficult for magnetic flux to pass through. Mixing the powder makes it easier to pass the magnetic flux.

The slotless radial gap type motor of the present invention can be applied to, for example, a motor for driving an air conditioner compressor, an industrial servomotor, a motor for an electrically driven vehicle, and the like.

It should be noted that the present invention is not limited to only the above-described embodiment, and can be appropriately modified and implemented without changing the gist.

[0028]

According to the slotless radial gap type motor of the present invention, since there is no need to provide teeth for winding the winding around the stator, iron loss caused by the teeth can be prevented. In addition, since there is no slot, torque ripple can be prevented. Thereby, the efficiency of the motor is improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing the structure of a slotless radial gap motor according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the slotless radial gap motor according to the embodiment of the present invention.

FIG. 3 is a perspective view showing the structure of a radial gap type motor according to a conventional example.

FIG. 4 is a cross-sectional view of a radial gap type motor according to a conventional example, and a diagram showing an arrangement relationship and connection states of respective coils.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Stator 11 ... Stator iron core 12 ... Tooth part 13 ... Slot (groove) 14 ... Electromagnetic steel plate 2 ... Rotor 21 ... Rotor iron core 22 ... Permanent magnet 3 ... Rotating shaft 4 ... Coil 41 ... U-phase coil 42 ... V-phase coil 43 ... W-phase coil 5 ... Gap 6 ... Mold winding 61 ... Mold material

Claims (3)

[Claims] A stator comprising a cylindrical stator core; a plurality of phase windings provided on an inner peripheral side of the stator core; and a plurality of windings disposed on an inner peripheral surface of the stator core. A holding member for holding, arranged in a hollow portion of the stator, and configured by attaching a plurality of permanent magnets to the stator side of a rotor core, and rotating with a predetermined gap from the holding member. A slotless radial gap type motor, comprising: a rotor that can be used; 2. The slotless radial gap motor according to claim 1, wherein said holding member is made of a molding material. 3. The slotless radial gap motor according to claim 1, wherein magnetic powder is mixed into said holding member.