JP2001333562A - Coreless axial gap motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coreless axial gap motor, capable of improving efficiency by eliminating a difference in magnetic flux interlinking at respective conductors of a winding, thereby suppressing loss. SOLUTION: This motor consists of a retaining member (70) for retaining a plurality of phases of windings (71 to 73) and a hollow and disc-shaped rotor core (21). At the surface of the rotor core (21), a plurality of permanent magnets (22) are fixed. The permanent magnets (22) includes a rotor (2), which is rotatable in the presence of the retaining means (70) and a prescribed gap. The windings (71 to 73) are formed of a linear member provided with the plurality of conductors.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art FIGS. 4A and 4B show the structure of a conventional axial gap type motor. FIG. 4A is a plan sectional view of a permanent magnet of a rotor viewed from an axial direction, and FIG. It is. This axial gap type motor includes a stator 1, two rotors 2 and 2, a rotating shaft 3, and the like.

The stator 1 has a hollow disk shape having a diameter of 200 mm.
On both sides of a stator core 11 of about mm, 24 slots (grooves) 12 are provided at regular intervals in the circumferential direction. These slots 12 are used for the stator core 11
Respectively, penetrates from the inner circumference to the outer circumference of the stator core 11 so as to form a radial shape on the surface. A coil (winding) is wound around these slots 12 as described later. The two rotors 2 and 2 are each provided with eight permanent magnets 2 having a fan shape on the surface of a rotor core 21 having a hollow disk shape.
2, and each permanent magnet 22 is magnetized with N poles and S poles alternately arranged. In the two rotors 2 facing each other, the N pole and the S pole are arranged so as to face each other.

[0004] The stator 1 and the rotors 2 are, for example, 1 mm.
The slots 12, that is, the coils and the permanent magnets 22, are arranged so as to have a gap 4 of about the same degree. The rotating shaft 3 is fitted into the hollow portion of the rotor core 21, and the rotating shaft 3 is inserted into the hollow portion of the stator core 11. The stator 1 and the rotors 2 and 2 are housed in a frame 5, and the outer peripheral portion of the stator 1 is fixed to the inner wall surface of the frame 5. Further, a bearing 6 for rotating the rotating shaft 3 is provided in an opening of the frame 5 through which the rotating shaft 3 is inserted. As a result, the rotors 2 and 2 can rotate with respect to the stator 1 with the gaps 4 respectively. For example, a fan or the like for an air conditioner is attached to the tip of the rotating shaft 3.

FIG. 5 is a partial cross-sectional view in the radial direction of the axial gap motor, in which the permanent magnet 22 is divided into two poles.
That is, it is a diagram showing a quarter of the stator 1 and one rotor 2. 5, the same parts as those in FIG. 4 are denoted by the same reference numerals. One of a U-phase coil 101, a V-phase coil 102, and a W-phase coil 103 is inserted into and wound around each slot 12 formed in the stator core 11 of the stator 1.

[0006] As shown in FIG.
2 and 103 are wound around the corresponding two slots 12, respectively, and the two slots are separated from each other by three slots. These coils 10
The coils 1, 102, and 103 are wound in two stages vertically in the axial direction of the stator core 11 so that the upper and lower coils do not electrically contact each other. In this case, both upper and lower
In the circumferential direction of the stator core 11, the U-phase coil 101, V
The phase coil 102 and the W-phase coil 103 are wound in this order.

In the axial gap type motor having the above-described configuration, the coils 101, 102,
A magnetic field is generated by passing an electric current through 103, and a magnetic attraction and repulsion between the stator 1 and each of the permanent magnets 22 generates a torque. Rotates with.

[0008]

In the conventional axial gap type motor having the above-described structure, since the stator core is provided, there is a problem that iron loss occurs and efficiency is deteriorated. Therefore, a coreless axial gap type motor that does not use a stator core has been considered.

FIG. 6 is a sectional view showing a coil portion of an axial gap type motor. FIG. 6A shows a core structure provided with a stator core, and FIG. 6B shows a coreless structure provided with no stator core. FIG. The coreless structure shown in FIG. 6B has an advantage that there is no iron loss generated in the core structure of FIG. 6A, but since there is no core through which the magnets pass intensively, the magnetic flux is directly linked to the coil. Intersect.

FIG. 7 is a diagram showing parallel conductors in a coil having the coreless structure. When one turn is formed of a parallel conductor composed of a plurality of conductors (conductors) in order to increase the cross-sectional area of the coil and reduce copper loss, as shown in FIG. The area (the area shown by the oblique line rising upward) A1 is different from the area (the area shown by the oblique line falling downward) B1 formed by the loop formed by the outer conductor B (B1> A1). For this reason, a difference occurs in the magnetic flux linked to each conductor constituting the parallel conductor, and when the motor is rotating, a potential difference occurs in each conductor of the parallel conductor, a circulating current flows, and a problem occurs that loss occurs. is there.

SUMMARY OF THE INVENTION An object of the present invention is to provide a coreless axial gap motor in which loss is reduced and efficiency is improved by eliminating a difference in magnetic flux linked to each conductor of a winding.

[0012]

In order to solve the above-mentioned problems and achieve the object, a coreless axial gap motor according to the present invention is configured as follows.

A coreless axial gap motor according to the present invention comprises a holding means for holding windings of a plurality of phases, and a rotor core having a hollow disk shape. A plurality of permanent magnets are fixed on the surface of the rotor core. The permanent magnets are provided with a rotor rotatable with a predetermined gap between the permanent magnets, and the winding is formed of a linear member formed by twisting a plurality of conductors.

[0014]

FIG. 1 is a view showing a structure of a coreless axial gap motor according to an embodiment of the present invention. FIG. 1 (a) is a sectional plan view of a permanent magnet of a rotor viewed from an axial direction. (B) is a developed sectional view of the side surface. In FIG. 1, the same parts as those in FIG. 4 are denoted by the same reference numerals. The coreless axial gap motor includes a stator 1, rotors 2, 2, a rotating shaft 3, and the like.

In FIG. 1, a disk-shaped molded winding 7 is provided instead of the above-described stator 1, and the outer peripheral portion of the molded winding 7 is fixed to the inner wall surface of the frame 5. Other configurations are the same as those in FIG. 4, and the rotors 2 and 2 can rotate with the gap 4 existing with respect to the mold winding 7. 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 partial cross-sectional view in the radial direction of the axial gap type motor. The permanent magnets 22 are divided into two poles, that is, the mold winding 7 and the rotor 2, respectively.
FIG. 4 is a diagram showing a quarter of a second rotation; 2, the same parts as those in FIG. 1 are denoted by the same reference numerals. In the molded winding 7, a plurality of coils 71, 72, 73 previously wound in a ring shape so as to have the same shape as the coil (winding) wound in the slot 12 shown in FIG. Have been.

The coils 71, 72 and 73 are held in two stages in the radial direction of the stator 1 so as to correspond to the respective rotors 2 and 2 so that the upper and lower coils are not in electrical contact with each other. I have. In this case, the U-phase coil 71, the V-phase coil 72, and the W-phase coil 73 are held in the circumferential direction of the molded winding 7 in the upper and lower stages in this order.

Each coil 71, 7 in the molded winding 7
As the 2,73 conductors (conductors), stranded copper wires (Litz wires) formed by thin wires are used. Also, the molding material 70
Is made of a casting resin (resin). An example of this resin is a heat-curable epoxy casting resin filled with a filler and having a curing temperature of 75 to 80 ° C / 2 to 3H + 105.
C./2 to 3H, 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 70.

In the coreless axial gap motor having the above configuration, each coil 7
When a current is passed through 1, 72, 73, a magnetic field is generated,
Magnetic flux passes through the mold winding 7. A torque is generated by magnetic attraction and repulsion between the mold winding 7 and each of the permanent magnets 22 with this, and the rotors 2 and 2 rotate together with the rotating shaft 3.

FIG. 3 is a diagram showing conductors in the coil having the coreless structure. Each of the above coils 71, 72, 7
In FIG. 3, one turn of the coil is formed by twisting (twisting) a plurality of conductors (conductors) to form a more linear shape, thereby forming a loop formed by the conductors A and B as shown in FIG. Make the same area C (shaded area). For this reason,
There is no difference in the magnetic flux linking these conductors, and when the motor is rotating, no potential difference occurs in these conductors and no circulating current flows. Furthermore, the magnetic powder is mixed with the molding material of the molding winding to make it easier to pass magnetic flux. This reduces losses and increases motor efficiency.

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.

[0023]

According to the coreless axial gap type motor of the present invention, the winding is composed of a linear member in which a plurality of conductors are twisted. The difference in the intersecting magnetic flux disappears. As a result, it is possible to prevent a potential difference between the conductors of the winding, and to eliminate the circulating current flowing between the conductors, thereby reducing the loss and improving the efficiency.

[Brief description of the drawings]

FIG. 1 is a view showing a structure of a coreless axial gap type motor according to an embodiment of the present invention, wherein (a) is a plan sectional view of a permanent magnet of a rotor viewed from an axial direction, and (b) is a side view of the permanent magnet. FIG.

FIG. 2 is a partial cross-sectional view in the radial direction of the coreless axial gap motor according to the embodiment of the present invention.

FIG. 3 is a diagram showing conductors in a coil having a coreless structure according to the embodiment of the present invention.

4A and 4B are diagrams showing a structure of an axial gap type motor according to a conventional example, wherein FIG. 4A is a plan sectional view of a permanent magnet of a rotor viewed from an axial direction, and FIG.

FIG. 5 is a partial cross-sectional view in the radial direction of an axial gap type motor according to a conventional example.

FIG. 6 is a cross-sectional view showing a coil portion of an axial gap type motor according to a conventional example, in which (a) shows a core structure provided with a stator core, and (b) shows a coreless structure provided with no stator core. FIG.

FIG. 7 is a diagram showing parallel conductors in a coil having a coreless structure according to a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Stator 11 ... Stator iron core 12 ... Slot 2 ... Rotor 21 ... Rotor iron core 22 ... Permanent magnet 3 ... Rotation shaft 4 ... Gap 5 ... Frame 6 ... Bearing 7 ... Mold winding 70 ... Mold materials 71-73 … Coils (windings)

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5H603 AA07 BB09 BB14 CA01 CA05 CB02 CC04 CC06 CC14 CC17 CD01 CD21 CE01 EE02 5H604 BB13 CC01 CC04 CC12 DA15 DB02 PE06 5H621 BB07 GA02 GA07 GA12 GA14 GB03 HH01 JK02 JK05 JK07

Claims (1)

[Claims] The present invention comprises a holding means for holding windings of a plurality of phases, a rotor core having a hollow disk shape, and a plurality of permanent magnets fixed to the surface of the rotor core. A coreless axial gap motor, comprising: the holding unit; and a rotor rotatable with a predetermined gap therebetween, wherein the winding is formed of a linear member formed by twisting a plurality of conductors. .