JP2003174743A - Rotary machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To attain restraint of loss due to eddy current and little heat dissipation even if a bulk material is used in a rotor. <P>SOLUTION: A bulk material flat plate 52 is divided into a plurality of portions in a condition insulated by insulation film to restrain loss due to eddy current. A thermal conduction sheet 54 is provided between the bulk material flat plates 52, thus attaining satisfactory heat dissipation. <P>COPYRIGHT: (C)2003,JPO

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 that reduces loss due to eddy currents and improves heat transfer when a bulk material is used for a rotor.

[0002]

2. Description of the Related Art Conventional synchronous motors include reluctance motors whose rotors are composed only of laminated cores, and permanent magnet motors whose rotors have permanent magnets (including cases where magnets are embedded in laminated cores). . Applications of this synchronous motor include, for example, electric vehicles (including so-called hybrid vehicles), and high-speed rotation is achieved.

Conventionally, in reluctance motors or permanent magnet motors (embedded magnets), laminated electromagnetic steel sheets have been used for laminated cores in order to reduce iron loss. However, since the electromagnetic steel plate is expensive, it has been attempted to use a relatively inexpensive bulk material (soft magnetic material such as S45C) as a material to replace the electromagnetic steel plate.

Regarding the permanent magnet motor, a technique of dividing the permanent magnet in order to suppress the generation of eddy current and prevent thermal demagnetization is disclosed in, for example, Japanese Patent Laid-Open Nos. 2000-245085 and 2000-228838. It is described in the official gazette. Further, in a rotor in which the entire rotor is composed of permanent magnets, it is possible to alternately stack thin plate-shaped permanent magnets and soft magnetic materials in the rotor structure.
No. 50545.

[0005]

In a reluctance motor or a permanent magnet motor (embedded magnet type), if a bulk material is used for the rotor, iron loss increases and heat generation increases accordingly. Further, in a permanent magnet motor (embedded magnet type), when a permanent magnet is used for the rotor, if heat due to iron loss is transferred to the permanent magnet, magnet demagnetization may occur. However, in the past, stacking of bulk materials to reduce iron loss and stacking of magnets to prevent demagnetization of magnets due to heat have been carried out. No way to dissipate the heat was known.
Therefore, an object of the present invention is to provide a rotating electric machine that can solve the above problems. That is, it is an object of the rotating electric machine of the present invention to take measures against heat radiation in the rotor.

[0007]

That is, the present invention relates to a rotating electric machine including a rotor having a laminated core in which soft magnetic materials insulated from each other are laminated, and a heat generator is provided between the soft magnetic materials. A heat conductive member having conductivity is provided.

According to this, the loss due to the eddy current can be reduced, and the heat conducting member can be further improved by providing the heat conducting member between the soft magnetic materials.

Further, the present invention further includes a plurality of permanent magnets embedded by being divided into holes provided in the laminated core, and the heat conducting member is provided between the divided permanent magnets. May be.

According to this, since the heat generated by the loss in the soft magnetic material is transmitted through the heat conducting member and released, it is possible to suppress the demagnetization of the permanent magnet due to the heat.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described through embodiments of the invention.

[First Embodiment] FIG. 1 is a plan view showing a schematic configuration of a rotary electric machine 10 according to a first embodiment. Rotating electric machine 1
0 has a rotor 20 and a stator 30.

The rotor 20 has a shaft 40 rotatable about a rotation axis, a disc-shaped laminated core 50 (details will be described later) provided around the shaft 40, and a laminated core 50.
The permanent magnets 60 are embedded in the circumferential direction of the. The permanent magnet 60 may be divided into a plurality of pieces, and may be an integral member having the same thickness as the laminated core 50.

The stator 30 has a laminated core 32 made of an electromagnetic steel plate. A coil (not shown) is wound around the slots 34 and the teeth 36 of the laminated core 32.

FIG. 2 is a sectional view of the rotary electric machine 10 taken along the line AA ′ in FIG. The laminated core 50 is formed by laminating a plurality of flat plates (bulk material flat plates 52) of bulk materials (soft magnetic materials such as S45C) coated with an insulating film in the direction of the rotation axis G, and between the bulk material flat plates 52. 54 (for example, a silicon-based material) is provided. Note that reference numeral 38
Indicates the coil end of the coil wound around the laminated core 32.

As described above, the cost can be reduced by using the bulk material instead of the electromagnetic steel plate for the rotor.
Further, since the bulk material flat plate 52 is divided into a plurality of pieces while being insulated by the insulating film, the loss due to the eddy current is reduced, and the heat conduction sheet 54 is provided between the bulk material flat plates 52. As a result, heat dissipation can be further improved.

Here, the number of bulk material flat plates 52 (the number of divisions)
The verification result about is shown. FIG. 3 shows a graph showing the relationship between the number of divisions and the loss ratio. The loss ratio indicates a relative loss in each division number based on the loss when the division number is one. The loss ratio P indicates the loss ratio when a conventional electromagnetic steel plate is used for the rotor. From this graph, it is understood that when the number of divisions is about 16, the loss is reduced to the same level as the loss ratio of the conventional electromagnetic steel sheet. Therefore, as the structure of the rotor 20, the bulk material flat plate 52 is provided in a predetermined amount (for example, 1
It is preferable to use 6 or more sheets.

[Second Embodiment] FIG. 4 is a sectional view of a rotary electric machine 12 according to a second embodiment. The basic configuration of the rotary electric machine 12 of the present embodiment is the same as the configuration of the rotary electric machine 10 of the first embodiment, and the same portions will be denoted by the same reference numerals and description thereof will be appropriately omitted. The rotor 20 of the rotating electric machine 12 includes a permanent magnet 6
0 is divided into a plurality, and between the divided permanent magnets 60,
It has a structure in which a heat conductive sheet 80 is provided.

As a result, the heat generated by the loss in the flat plate 52 of the bulk material is transmitted through the heat conductive sheet 80 and released, so that the demagnetization of the permanent magnet 60 due to the heat can be suppressed.

In the above embodiment, the permanent magnet motor in which the permanent magnet is embedded in the laminated core has been described as an example, but the reluctance motor having no permanent magnet in the rotor is shown in the first embodiment. A laminated core in which a bulk material having an insulating film and an insulating sheet are alternately laminated may be used.

[0021]

As is apparent from the above description, according to the present invention, in the laminated core of the rotor of the rotary electric machine, the loss due to the eddy current can be reduced and the thermal discharge property can be improved.

Further, by providing a heat conductive sheet between the divided permanent magnets, the heat conductivity can be further improved.

[Brief description of drawings]

FIG. 1 is a plan view showing a schematic configuration of a rotary electric machine 10 according to a first embodiment.

FIG. 2 is a cross-sectional view of the rotary electric machine 10 taken along the line AA ′ of FIG.

FIG. 3 is a graph showing the relationship between the number of divisions and the loss ratio.

FIG. 4 is a sectional view of a rotary electric machine 12 according to a second embodiment.

[Explanation of symbols]

10, 12 rotating electric machine, 20 rotor, 30 stator,
32 laminated core, 34 slots, 36 teeth, 38
Coil end, 40 shaft, 50 laminated core, 5
2 flat plate of bulk material, 54 heat conductive sheet, 60 permanent magnet, 80 heat conductive sheet.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H02K 19/10 H02K 19/10 A 5H622 21/14 21/14 M 29/00 29/00 Z (72) Inventor Toshimitsu Takahashi 1st Toyota-cho, Toyota-shi, Aichi F-term in Toyota Motor Corporation (reference) 5H002 AA03 AA10 AB01 AD00 5H019 AA04 CC03 DD01 EE14 5H609 BB03 BB12 PP02 PP07 QQ23 RR58 RR69 RR69 BB06 PP02 PP13 BB06 PP02 PP13 5H621 GA01 HH01 JK11 5H622 AA06 CA02 CB03 PP03 PP07

Claims (2)

[Claims] 1. A rotary electric machine including a rotor having a laminated core formed by laminating soft magnetic materials insulated from each other, wherein a heat conductive member having thermal conductivity is provided between the soft magnetic materials. A rotating electrical machine characterized by being. 2. The heat conduction member is further provided between the divided permanent magnets, further comprising a plurality of divided permanent magnets embedded in holes provided in the laminated core. The rotating electrical machine according to claim 1.