JP2004260951A - Permanent magnet type motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a permanent magnet type motor capable of realizing lower eddy current loss with efficient work. <P>SOLUTION: The permanent magnet type motor comprises a rotor where a permanent magnet 1 is arranged on its surface. A plurality of grooves 2 are axially provided on the surface of the permanent magnet 1 of the rotor. So, the eddy current loss that occurs on the surface of the permanent magnet 1 is reduced. A resin coating 3 is applied on the surface of the permanent magnet 1 including the groove 2. Thus, the mechanical strength of the permanent magnet 1 is assured while oxidation of the permanent magnet 1 is prevented. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a permanent magnet type electric motor having a rotor having a permanent magnet disposed on a surface.
[0002]
[Prior art]
In this type of conventional motor, the shape of the permanent magnet attached to the rotor is determined for the purpose of reducing cogging torque and reducing harmonic components of induced voltage. Further, the surface treatment of the permanent magnet is determined based on environmental resistance. Therefore, the harmonic eddy current loss generated on the surface of the permanent magnet is determined by the current waveform of the driver.
Conventionally, in order to reduce the eddy current loss generated on the surface of the permanent magnet, the rotor is configured by dividing the permanent magnet into a plurality of parts and arranging them in the axial direction (for example, see Patent Document 1).
[0003]
[Patent Document 1]
JP-A-11-252835 (FIG. 1)
[0004]
[Problems to be solved by the invention]
However, such a conventional technique has a problem in that the number of permanent magnets is increased, alignment and fixing of magnetic poles are troublesome, and work efficiency is poor.
The present invention has been made in order to solve such a problem, and an object of the present invention is to provide a permanent magnet type electric motor capable of efficiently reducing eddy current loss.
[0005]
[Means for Solving the Problems]
In order to solve the above problem, the present invention provides a permanent magnet type motor having a rotor having a permanent magnet disposed on a surface thereof, wherein a plurality of grooves are provided in an axial direction on a surface of the permanent magnet of the rotor. Things.
Further, the surface of the permanent magnet including the groove is coated with a resin.
[0006]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIG.
FIG. 1 is a perspective view of a permanent magnet showing an embodiment of the present invention.
In the present invention, as shown in FIG. 1, a plurality of grooves 2 are provided in a permanent magnet 1 disposed on a surface of a rotor in an axial direction to divide the surface of the permanent magnet.
By doing so, a large loop of the eddy current flowing on the surface of the permanent magnet can be cut off, and the eddy current is reduced. Particularly in the case of harmonics, the eddy current is concentrated on the surface due to the skin effect, so that the effect is large.
Since the number of the permanent magnets 1 does not change, no special pole alignment is required, and only the grooves are formed, the working efficiency is extremely high as compared with the related art.
In this embodiment, the resin coating 3 is applied to the surface of the permanent magnet 1 including the groove 2 by using a resin having a high electric resistance. By doing so, the mechanical strength of the permanent magnet 1 is ensured, and the oxidation of the permanent magnet 1 is prevented.
[0007]
【The invention's effect】
As described above, the present invention has the following effects.
(1) By providing grooves on the surface of the permanent magnet, eddy current loss generated on the surface of the permanent magnet can be reduced.
(2) By applying a resin coating to the surface of the permanent magnet including the groove, it is possible to secure the mechanical strength of the permanent magnet and prevent oxidation of the permanent magnet.
[Brief description of the drawings]
FIG. 1 is a perspective view of a permanent magnet according to an embodiment of the present invention.
[Explanation of symbols]
1 permanent magnet 2 groove 3 resin coating

Claims (2)

In a permanent magnet type motor having a rotor having a permanent magnet disposed on a surface,
A permanent magnet type electric motor, wherein a plurality of grooves are provided in a surface of a permanent magnet of the rotor in an axial direction. The permanent magnet type electric motor according to claim 1, wherein a surface of the permanent magnet including the groove is coated with a resin.

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