JPH04127860A - Magnetizer for electric rotating machine - Google Patents

Abstract

PURPOSE:To impart a predetermined magnetizing wave-form on an object to be magnetized by producing a parallel field having high flux density by means of a superconducting magnet and then introducing the parallel field to a rare earth metal object to be magnetized by means of a magnetizing yoke. CONSTITUTION:When an object is magnetized, a pair of arched objects 16 to be magnetized are disposed vertically in the object holding section 26 of a magnetizing yoke 22 and then the magnetizing yoke 22 is disposed on the inside of a superconducting magnet 20 with a magnetizing core 24 being disposed between the pair of objects 16. When the superconducting magnet 20 is excited to produce high density magnetizing flux 32, the magnetizing flux 32 passes through the inside of the superconducting magnet 20 in parallel therewith while being guided by the magnetizing yoke 22. At that time, the superconducting magnet 20 prevents leakage of the magnetizing flux 32 through Meissner effect. Since the magnetizing flux is introduced, as it is, to the object to be magnetized the object is fully magnetized with high flux density.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetizing device for a rotating electrical machine, and particularly to a magnetizing device for a rotating electrical machine for magnetizing a rare earth isotropic magnet.

[Prior Art] Today, as magnetic materials used in magnets, rare earths and the like, which require a large coercive force for magnetization, are often used. In particular, magnets made of rare earth materials are often attached to the stator side of rotating machines such as motors and generators.

However, in order to magnetize such rare earth metals, it is necessary to
A uniform high magnetic flux density with a high magnetomotive force on the order of 50 km/hr is required.

For this reason, there was a problem in that conventional magnetizing devices could not satisfactorily fully magnetize the magnet (magnetization rate of 100%).

FIG. 5 shows an example of a conventional inner tube type magnetizing device, in which a coil 0 is arranged inside a motor M,
The stator side magnets 12, 12 made of rare earth or the like are magnetized from the inside.

[Problem to be solved by the invention] However, this conventional device does not generate enough magnetic flux,
Moreover, since only non-uniform magnetic flux densities can be obtained, there is a problem in that it is difficult to obtain a uniform high magnetic flux density that is necessary to reliably magnetize rare earth elements.

In particular, in a rotating electric machine such as a DC motor, the stator side magnet 12 is formed in an arc shape. Therefore, even if such arc-shaped magnets 12 are made of a magnetic material other than rare earth, if they are inserted into an inner tube using the prior art, each magnet 12 will be attached to both ends as shown in A in FIG. It is only magnetized in an uneven trapezoidal pattern with a peak and a slightly concave center.
The ideal shape of a beautiful sine curve as shown in B in the figure (
I could only fully magnetize it by turning. This caused a problem in that a large cogging torque was generated in the motor, increasing the vibration of the motor.

In addition, as another magnetization technique, an outer tube type magnetization device that magnetizes the magnet from the outside of the motor is also known. However, even if four magnets are attached using this technology, the magnetic flux will be concentrated in the center as shown in C in Figure 6, resulting in a pattern where the magnetic field strength is too small and the effective amount of magnetic flux is insufficient. A decrease in torque was unavoidable.

As another vibration reduction measure, it is known to use vibration isolating material such as rubber in the bracket part of the motor, but in this case, it becomes a problem as it increases the price of the motor. was.

Furthermore, as a recent example, as shown in Japanese Unexamined Patent Application Publication No. 63-260118, it is known that a cylindrical magnet with radial anisotropy is improved by a method of magnetization. In order to obtain a smooth magnetic flux distribution by partially magnetizing a part of the magnet, a decrease in maximum torque was unavoidable.

The present invention has been made in view of such conventional problems, and its purpose is to enable full magnetization of a rare earth isotropic magnet with a high magnetic flux density and to provide an ideal magnetic force distribution. It is possible to reduce the vibration of rotating electric machines without reducing the output.
An object of the present invention is to provide a magnetizing device for a rotating electric machine that can reduce noise.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a magnetizing device for a rotating electric machine that magnetizes a rare earth magnetized body to form an isotropic magnet for a stator of a rotating electric machine. A superconducting magnetic field generator that generates a parallel magnetic field with a high magnetic flux density using a superconducting magnet, and a superconducting magnetic field generator disposed within a parallel magnetic field with a high magnetic flux density generated from the superconducting magnet, and which transmits this parallel magnetic field to the rare earth magnetized body. a magnetizing yoke disposed within or between the magnetized body, and controlling a magnetic path so that the parallel magnetic field with high magnetic flux density passes through the magnetized body in accordance with a predetermined magnetization waveform. A magnetized core that applies a predetermined magnetizing waveform to a magnetized body.

[Function] In the magnetizing device for a rotating electrical machine having the above configuration, a superconducting magnet is used to generate a parallel magnetic field with a high magnetic flux density, and a magnetizing yoke is used to apply this parallel magnetic field to a rare earth magnetized body. lead. At this time, the Meissner effect, which is one of the superconducting phenomena, prevents leakage of magnetic flux to the outside, and the generated parallel magnetic field is guided to the magnetized object while maintaining a state of high magnetic flux density.

The present invention controls the high magnetic flux density parallel magnetic field guided to the magnetized object using a magnetized core placed within the magnetized object or between the magnetized objects, and It is characterized by applying a predetermined magnetization waveform.

As a result, it is possible to fully magnetize the magnetized object with high magnetic flux density, and also to achieve magnetization in an ideal magnetization pattern.As a result, there is no reduction in output, and the vibration and vibration of the rotating electric machine are reduced. It is possible to reduce noise.

Furthermore, the invention of claim (2) fully magnetizes the magnetized body in a pattern close to an ideal sinusoidal waveform even when the magnetized body has an arc shape like a stator-side magnet of a rotating electric machine. It becomes possible.

[Example] Next, a preferred example of the present invention will be described in detail based on the drawings.

FIG. 1 is a diagram showing a motor magnetizing device according to an embodiment of the present invention.

This motor magnetizing device magnetizes a rare earth isotropic magnet 18 such as samarium, cerium, neodymium, etc.
A superconducting magnet 20 for magnetization, a magnetization yoke 22,
A magnetized core 24 is provided.

The superconducting magnet 20 generates a large magnetic flux for magnetizing the rare earth isotropic magnet 18, and is designed to generate a parallel magnetic field with a high magnetic flux density.

The magnetizing yoke 22 is disposed inside the superconducting mucket 20 to guide a parallel magnetic field with a high magnetic flux density from the superconducting mucket 20. The magnetized yoke 22 has a magnetized body holding portion 26 approximately in the center thereof, and the magnetized body 16 is housed within this magnetized body holding portion 26 . This magnetized body 16 has an arc shape. Further, the magnetized body holding section 26 is formed into a cylindrical shape so that two arcuate magnetized bodies 16 can be disposed at upper and lower positions while maintaining close contact with each other.

Furthermore, in this embodiment, the thickness tl of the portions located on both left and right sides of the magnetized body holding portion 26 is set smaller than the thickness t2 of the magnetized body 16.

The magnetized core 24 is arranged between the magnetized bodies 16 in the magnetized body holding section 26 .

The magnetized core 24 also includes a circular center portion 28 and an arcuate magnetized body contact portion 30 that protrudes above and below the circular center portion 28 and comes into close contact with the magnetized body 16 .

The range θ of the contact surface 32 of the magnetized body contact portion 30 with respect to the magnetized body 16 is set smaller than the magnetization range α of the magnetized body 16. Further, the circular center portion 28 is
The radius r1 is set to be shorter than the distance r2 from the center of the central portion 28 to a line X connecting the ends of the upper and lower magnetized body contact portions 30.

Furthermore, a non-magnetic material 34 is disposed in a portion of the magnetized object holding section 26 other than the magnetized core 24.

Next, a state in which the magnetized body 16 is magnetized using the motor magnetizing device will be described.

First, a pair of arc-shaped magnetized bodies 16 were arranged at upper and lower positions in the magnetized body holding portion 26 of the magnetizing yoke 22, and a magnetized core 24 was arranged between the pair of magnetized bodies 16. In this state, the magnetizing yoke 22 is disposed inside the superconducting magnet 20.

Next, when the superconducting magnet 20 is energized and excited to generate a high-density magnetizing magnetic flux 32, this magnetizing magnetic flux 3
2 are guided in parallel inside the superconducting magnet 20 by the magnetizing yoke 22 and pass through it.

At this time, the superconducting magnet 20 prevents the leakage of the magnetizing magnetic flux 32 to the outside due to the Meissner effect, which is the origin of the superconducting phenomenon. Therefore, the generated magnetizing magnetic flux 32 is directly guided to the magnetized body 16.

Further, the magnetizing magnetic flux 32 guided to the magnetized body 16 tries to pass through the magnetized core 24 in parallel to the exit (lower end) side, but the magnetized body contact portion 30 of the magnetized core 24 The range θ of the contact surface is set smaller than the magnetization range α of the magnetized body 16, and moreover, in the central part of the magnetized body 16 where the magnetized core 24 is in contact, Since both ends of the magnetized body contact portion 30 face the center of the magnetized core 24 in a sector shape, the magnetizing magnetic flux 32 guided parallel to the magnetized body 16 is constricted in a sector shape at a predetermined angle and radially directed. pass through.

On the other hand, the magnetized core 24 is not in contact with the both ends, and moreover, due to the presence of the non-magnetic material 34, the non-magnetic material 34
Although the nearby magnetizing magnetic flux 32 is slightly attracted to the magnetized core 24, it proceeds in the complete radial direction, and as it goes to the edge of the magnetized object 6, it becomes deviated from the center of the magnetized core 24. As it goes further to the end, it is pulled by the magnetizing yoke 22 and begins to move in a slightly reverse radial direction.

In this case, since the thickness tl of the portions located on both left and right sides of the magnetized object holding portion 26 is set smaller than the thickness t2 of the magnetized object 16, a large amount of the magnetizing magnetic flux 32 is attached. There is no flow to both the left and right sides of the magnetic body holding portion 26, and therefore a large amount of the magnetizing magnetic flux 32 can be prevented from flowing in the opposite direction to the radial direction on both sides of the magnetized body 16.

Further, the center portion 28 of the magnetized core 24 has a radius of “1”.
Since the distance from the center of the central portion 28 to the line magnetic flux 32
It is possible to prevent the magnet from being drawn to the magnetized core 24 more than necessary and flowing in the radial direction.

As described above, according to the present invention, even when the magnetized body 16 has an arc shape like a stator side magnet of a motor, it is possible to fully magnetize it in an almost ideal pattern. . Therefore, the magnetized magnet has a typical magnetization pattern of a sine waveform as shown in C in FIG.

FIG. 2 shows a state in which the rare earth isotropic magnet 8 thus formed is incorporated into a DC motor, in which numeral 36 is a rotor and numeral 38 is a yoke. The magnet 18 is
As shown by the arrows in the figure, the lines of magnetic force are oriented in the radial direction at the center, and the lines of force are gradually directed outward at both ends, resulting in a sine waveform as shown in C in Figure 6. . Therefore, the cogging torque can be significantly reduced without reducing the maximum torque of the DC motor, and the vibration of the DC motor during rotation can be reduced, resulting in smooth motor rotation.

Another embodiment of the invention is shown in FIGS. 3 and 4.

In this embodiment, a cylindrical magnetized body 40 is disposed within the magnetized body holding portion 26 of the magnetizing yoke 22 arranged inside the superconducting macnet 20, and the magnetized body 40 is placed inside the magnetized body 40. A cylindrical magnetized core 42 is provided in contact with the inner surface of the magnetic body 40.

FIG. 4 shows a state in which the magnet 44 formed in this manner is assembled into a motor. In this case, the lines of magnetic force run in parallel from above to below, as shown by the arrows in the figure. In addition, in the figure, 46 is a rotor, and 48 is a yoke.

Note that the present invention is not limited to the above embodiments,
Various modifications can be made within the scope of the invention.

For example, in the embodiment, two types of magnetized cores 24
．． Although the case where magnetization is carried out using 42 has been described, the case is not limited to the above example, and magnetization in various states can be achieved by changing the shape of the magnetization core.

Further, although the magnetizing yoke 22 is integral, it may have a divided shape, and furthermore, it is also possible to set the thickness tl of the left and right portions of the magnetized body holding portion 26 to zero.

Furthermore, in the embodiment, the superconducting magnet 20
Although the description has been made taking as an example the case where the magnetizing yoke 22 is located inside the superconducting magnet 20, the present invention is not limited to this. For example, in the case where the parallel magnetic field generated by the superconducting magnet 20 is guided using a cylindrical superconducting guide part, the magnetizing yoke 22 may be arranged within this superconducting guide part.

[Effects of the Invention and Invention] As explained above, according to the present invention, there is provided a magnetizing device for a rotating electrical machine that can easily fully magnetize a rare earth-based magnetized material at a high magnetic flux density. There is an effect that can be obtained.

In particular, according to the present invention, by controlling the magnetization waveform of the magnetized object by the shape of the magnetizing core within the magnetized object or between the magnetized objects, magnetization is achieved in an ideal magnetization pattern. As a result, the vibration of rotating electric machines can be reduced without reducing the output.
This has the effect of reducing noise.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing a magnetizing device for a rotating electric machine according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of a motor using a magnet formed by the magnetizing device for a rotating electric machine of FIG. 1, FIG. 3 is a sectional view showing a magnetizing device for a rotating electrical machine according to another embodiment of the present invention, and FIG. 4 is a sectional view of a motor using magnets formed by the magnetizing device for a rotating electrical machine of FIG. 3. , FIG. 5 is a sectional view showing a conventional magnetizing device, and FIG. 6 is a characteristic diagram showing a magnetization pattern by the magnetizing device. 16.40...Magnetized body, 18.44...Magnet, 2
0... Superconducting magnet, 22... Magnetizing yoke, 2
4.42... Magnetizing core, 32... Magnetic flux for magnetization. Agent: Patent attorney, Futsuo (and 2 others)

Claims (2)

[Claims] (1) Superconductivity, which uses a superconducting magnet to generate a parallel magnetic field with high magnetic flux density, in a magnetizing device for rotating electrical machines that magnetizes rare earth magnetized materials to form isotropic magnets for rotating electrical machine stators. a magnetic field generator, a magnetizing yoke disposed within a high magnetic flux density parallel magnetic field generated from the superconducting magnet and guiding this parallel magnetic field to the rare earth magnetized body, and a magnetized yoke within the magnetized body or between the magnetized bodies. a magnetizing core that is arranged in a magnetic field and controls a magnetic path so that the high magnetic flux density parallel magnetic field passes through the magnetized object in accordance with a predetermined magnetization waveform; A magnetizing device for a rotating electrical machine characterized by imparting a magnetic waveform. (2) In claim (1), the magnetized core has a contact surface with the magnetized body set to be smaller than a magnetization range of the magnetized body, and the magnetic flux of the magnetized body is weak at both ends and becomes central. 1. A magnetizing device for a rotating electric machine, characterized in that the magnetizing device is formed to obtain a magnetizing waveform that gradually becomes stronger as the temperature increases.