JPS6054408A - Toroidal magnet - Google Patents

Abstract

PURPOSE:To obtain a large energy product by forming a toroidal metal magnet thin body. CONSTITUTION:A magnetic field is applied to a metal magnet thin body 1 and thereby it is magnetized in the width direction indicated by arrow 2. It is wound cylindrically in order to obtain a toroidal magnet. In this case, when plate thickness of thin body 1 is sufficiently smaller than the width of sheet, magnetization can be reduced as compared with magnetization in the width direction. Therefore, a cylindrical magnet having a sufficiently small height can be formed and a variety of cylindrical toroidal magnet can be formed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to permanent magnets, and particularly to cylindrical so-called toroidal magnets.

[Technical background of the invention and its problems]

Permanent magnets can generally be classified into cast magnets, powder sintered magnets, compacted powder magnets, rubber magnets, and the like. When making cylindrical magnets from these magnets, cast magnets, sintered magnets, and compacted magnets are machined into the desired shape from block materials, or processed or formed after forming using a mold of the desired shape. , post-sintering processing, etc. are used, and in the case of rubber magnets, sheet magnets are wound in a toroidal shape.

However, in the former type of magnet, the magnet alloy is generally brittle and difficult to process. Another drawback is that magnetization in the radial direction is difficult. In the case of the latter magnet, the energy product is small and it is not practical.

[Purpose of the invention]

The present invention has been made in order to eliminate the drawbacks mentioned in (1) and (2) above, and it is possible to easily manufacture a cylindrical toroidal magnet having a large energy product and an arbitrary shape, and furthermore, it is easy to magnetize in the radial direction. The purpose is to provide a toroidal magnet.

[Summary of the invention]

The inventors have discovered that the object can be achieved by winding a thin metal magnet in a toroidal manner.

When making a cylindrical magnet magnetized in the radial direction, a magnetic field is applied in the entrance direction to the thin metal magnet (1) as shown perspectively in Figure 1, and the magnetic field is applied in the width direction of the arrow (2). It was magnetized. This is rolled into a cylindrical shape to obtain a desired cylindrical nodroidal magnet (3) as shown in FIG. At this time, if the thickness of the thin metal magnet (1) is made sufficiently smaller than the width of the sheet, demagnetization will not occur with respect to magnetization in the width direction. Therefore, a cylindrical magnet with a sufficiently small height h can be manufactured, and various cylindrical toroidal magnets can be manufactured. Usually, a thin metal magnet can be produced by processing a magnet alloy into a thin plate shape or directly forming a molten alloy into a thin plate shape.

Toroidal metal magnet materials made from thin sheets according to the present invention include Pt-Co-magnet, Fe-0
An r-Co magnet, a rare earth magnet, an Au-Co magnet, etc. can be used.

[Embodiments of the invention]

Example 1 Nd in the atomic range as a metal magnet material! I6 Pe7o
A thin alloy body was produced using the Oki roll method shown in FIG.

In the figure, Oυ is the container, 0 is the induction heating coil, and o3 is the induction heating coil.
1 indicates the nozzle, and (the circle indicates the roll. At this time, the roll diameter was 150φ and the rotation speed was 500 rpm. The obtained thin body (1) was in the form of a ribbon with a thickness of about 100 μm. Line diffraction revealed that it was amorphous.

This was wound around a ring having an outer diameter of 20φ to produce a toroidal core as shown in FIG. 2 (17). After heat-treating this at 300°C for 30 minutes, we magnetized it in the height direction and measured the magnetization, and found that the residual magnetic flux density was 6.5 kG%, and the coercive force was 6.5000 e.
value was obtained, confirming that it was a permanent magnet.

Example 2 Fe-25Cr-10Co-0,58i alloy in Example 1
It was produced using the same method as . The shape of the obtained thin body was a tape having a thickness of about 100 μm and a width of about 30111111 mm. X-ray diffraction revealed that it was crystalline and had a single alpha phase.

As shown in Figure 1, a magnetic field of 5 kOe was applied in the width direction of the tape, and the tape was cooled slowly from 640°C to room temperature at a cooling rate of 20"07 hours. After that, it was magnetized in the width direction and the magnetization curve was As a result of the measurement, we obtained a residual magnetic flux density of 14 kG, a coercive cuff of 000e, and a maximum energy product of 5.8 MGOe.By winding this around a ring with an outer diameter of 2oφ, it was magnetized in a more radial direction as shown in Figure 2. Moreover, we were able to obtain a magnet with a high energy product of 5.8 M GOe.

Similar experiments were also conducted on Pt--Co magnets and Au--Co magnet alloys, and high-performance toroidal magnets were successfully obtained.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a thin metal magnet used in the toroidal magnet of the present invention, FIG. 2 is a perspective view of the toroidal magnet of the present invention,
FIG. 3 is a perspective view showing an example of a manufacturing apparatus for a thin metal magnet used in the present invention.

Claims (4)

[Claims] (1) A toroidal magnet characterized by a thin metal magnet wound in a toroidal shape. (2) The toroidal magnet according to claim 1, wherein the thickness of the thin metal magnet is 200 μm or less. (3) The toroidal magnet according to claim 2, wherein the thin metal magnet is produced by ultra-quenching the thin metal magnet from a molten state. (4) The toroidal magnet according to claim 1, 2, or 3, wherein the toroidal magnet is magnetized in the radial direction.