JPS583366B2 - Manufacturing method of inductance element - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing an inductance element that applies a magnetic bias by inserting a permanent magnet into a magnetic core gap, and more particularly to a method for manufacturing an inductance element using a permanent magnet consisting of a plurality of magnet pieces. be.

Depending on the usage of the inductance element, direct current and alternating current may be used, and in this case, the magnetic core of the inductance element is used in a state close to magnetic saturation, and the magnetic permeability of the magnetic core is also extremely low. In many cases, the characteristics of the magnetic core cannot be used effectively.

To compensate for this, a method is used to effectively utilize the characteristics of the magnetic core by incorporating a permanent magnet into a part of the magnetic circuit of the soft magnetic core and applying a magnetic bias in the opposite direction to the DC magnetic field in advance to cancel out the DC magnetic field. is taken.

Ferrite magnets have a very large internal resistance of 10@4 Ω·cm or more, so they are used as permanent magnets for magnetic bias sources.

However, since ferrite magnets have low magnetic properties,
A large magnet is required to provide a large magnetic bias, which causes the inductance element to become large.

Therefore, to obtain a large magnetic bias, metal magnets such as alnico permanent magnets or rare earth cobalt magnets are required.

However, the magnetic core of the inductance element is 104Ω.
・Soft ferrite with high resistance of cm or more, such as N
i-Zn ferrite and Ou-Ni-Zn ferrite are used, but the metal magnet that provides the magnetic bias has low resistance depending on its material, so when alternating current is passed through the coil of the inductance element, vortices occur at the magnetic core in the magnetic circuit. Although current loss is relatively small, eddy current loss is large in the permanent magnet portion, which generates heat and changes the temperature of the entire inductance element, which can change the characteristics of the magnetic core.

The present invention provides a method for manufacturing an inductance element that eliminates the above-mentioned drawbacks, in which a permanent magnet is divided into a plurality of permanent magnet pieces, and the permanent magnet pieces are arranged on the air gap surface of the magnetic core of the inductance element. It is characterized by sandwiching the permanent magnet pieces, fixing the magnet pieces from the outer periphery of the permanent magnet pieces, and magnetizing the magnet pieces.

In an inductance element in which a permanent magnet is inserted into the magnetic core gap, electrical conduction between the permanent magnet segments can be reduced by using a permanent magnet group in which divided permanent magnet pieces are arranged in this permanent magnet part. This makes it possible to suppress the generation of eddy currents within the permanent magnet to an extremely low level.

In this way, the divided permanent magnet pieces must be fixed to the gap surface of the magnetic core so that the magnetization direction of each piece of the permanent magnet is aligned.

However, arranging them in this way would cause the same polarity to repel them, making it impossible to fit them within a given area.

Furthermore, the pieces of the permanent magnet overlap each other and cannot be arranged in an orderly manner.

Therefore, in the present invention, a group of permanent magnet pieces is arranged on the magnetic core gap surface and sandwiched between the magnetic cores, and the group of magnet pieces is fixed from the outer periphery of the group of permanent magnet pieces to prevent it from moving, and then the magnet pieces are magnetized. It is.

The present invention will be explained below based on Examples.

Fig. 1 is a front view of an inductance element manufactured according to the present invention, and Fig. 2 is an A-A of the inductance element in Fig. 1.
FIG.

FIG. 3 is a front view of another embodiment of the present invention.

In Figures 1 and 2, 1 is an E-type magnetic core made of soft ferrite, and the central leg 2 of this magnetic core 1 is slightly shorter than the outer leg 3, and there is a gap between the opposing parts of the central legs 2. It is occurring.

A divided permanent magnet piece 4 is inserted into this gap,
A winding frame 7 around which a coil 6 is wound is assembled on the outside with a thin plate 5 of an appropriate thickness interposed therebetween.

To manufacture this inductance element, a permanent magnet is divided into permanent magnet pieces 4.

The permanent magnet pieces 4 are arranged on opposing surfaces of the magnetic core 1 and sandwiched between the opposing magnetic cores.

Next, the group of permanent magnet pieces is fixed from the outer periphery with a thin plate 5, a winding frame 7 is assembled, and a coil 6 is wound.

Next, a sufficiently strong magnetic field is applied from the outside to magnetize this permanent magnet.

Also, the central leg 2 of the upper magnetic core 1 incorporates the winding frame 7 around which the coil 6 is wound, the permanent magnet piece group, and the winding frame 7 around which the coil 6 is wound.
The permanent magnet group can also be fixed by inserting a thin plate 5 into the gap between the two.

As shown in FIG. 3, in another embodiment of the present invention, divided magnet pieces 10 are lined up opposite the outer legs 9 of the magnetic core 8 and fixed from the outer periphery with a thin plate 11.

As explained above, the method for manufacturing an inductance element according to the present invention allows the permanent magnets of the magnetic bias source to be arranged in an orderly manner, and the assembly of the inductance element is extremely easy, resulting in a large industrial effect.

Furthermore, the manufactured inductance element has a small eddy current loss in the permanent magnet portion, making it possible to use a metal magnet that can provide a large magnetic bias.

[Brief explanation of the drawing]

FIG. 1 is a front view of an inductance element manufactured according to the present invention, and FIG. 2 is an A-A of the inductance element in FIG. 1.
FIG. FIG. 3 is a front view of another embodiment of the invention. 1, 8...Magnetic core, 4,10...Magnet piece, 5,11...Thin plate.

Claims (1)

[Claims] 1. In manufacturing an inductance element in which a permanent magnet is inserted into a magnetic core gap, a plurality of magnet pieces are arranged on the magnetic core gap surface,
A method of manufacturing an inductance element, which comprises sandwiching the magnet pieces between magnetic cores, fixing the magnet pieces from the outer periphery of the magnet pieces, and then magnetizing the magnet pieces.