JPS60214517A - Manufacture of ring permanent magnet magnetized in radial direction - Google Patents

Abstract

PURPOSE:To offer a ring permanent magnet in extremely simple means by radially magnetizing a permanent magnet which is made a closed ring and magnetized in transverse direction in the shape of a small piece or a widened shape consisting of a ring shape. CONSTITUTION:A ring or cylindrical permanent magnet 14 formed of cobalt samarium powder with an elastomer is fixed at the forward end of an arc contact 12 and is magnetized in the radial direction to generate magnetic field which traverses between the arc contacts 10 and 12 as shown by an arrow in the drawing. If the permanent magnet 14 is made of a bendable material, the magnet may be rolled into a ring in a cage 16 inserted inside of the back of the arc contact 12 and the smaller diameter part of the cage 16 may be inserted in the hole inside of the permanent magnet 14 to hold the permanent magnet and simultaneously to protect from arc.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method of manufacturing a radially magnetized annular permanent magnet.

(Prior Art) Permanent magnets play an important role in the field of electrical technology, and as their materials and performance improve, their potential applications continue to expand.

The application method disclosed in French Patent No. 2,480,028 is a magnetic blowing method that rotates the arc of an electric switch. One of the embodiments described in this patent uses radially magnetized annular or hollow cylindrical permanent magnets.

(Problems to be Solved by the Invention) However, in manufacturing such an annular permanent magnet f, a serious problem arises, especially when the magnet is an alloy of ferrite g and cobalt rare earth.

In other words, when manufacturing such a permanent magnet, before the sintering process, in order to ensure magnetization in the desired magnetization direction, the raw material powder must be placed in a magnetic field raised to 3 and compacted. have to start from. That is, special equipment and advanced skills are required.

The object of the invention is to provide a method for realizing a radially magnetized annular permanent magnet with extremely simple means.

(Means and effects for solving the problem) The manufacturing method according to the present invention first creates an expanded-shaped magnet magnetized in the transverse direction, and then creates a magnet based on this expanded-shaped magnet. It is characterized by the realization of a radially magnetized howler.

In the present invention, it is difficult to apply pressure and magnetize the magnet while it is in an annular shape, and this difficulty is naturally solved by making a magnet with an expanded shape. This work was carried out based on the fact that the magnet can be used in the structure of a tm-shaped magnet made using a tm-shaped magnet.

In the first embodiment of the present invention, the magnet is made into a small piece and its ends are brought into contact with each other to form an annular shape. It may be a polyhedron whose entire surface is flat, and the polyhedrons may be combined to form a polygon that has an overall annular shape. The presence of a gap between the contact surfaces of the joined pieces has no effect on the properties of the permanent magnet since the direction of magnetization is radial.

That is, the magnetization direction is parallel to the contact surface of the small piece.

Of course, the number of small pieces constituting the annular permanent magnet may be arbitrary.
By increasing the number, in the case of a polygon, it can be made closer to an annular shape.

In another embodiment according to the invention, the magnet is made of a flexible material and the annular shape is achieved by rolling it up and inserting it into a holding cage.

Such flexible magnets are made from a powder paste molded with known extomers. The magnetic force of such a flexible magnet is inferior to that of the hard magnet formed by abutting small pieces as described above.

According to the present invention, it is possible to extremely easily obtain a radially magnetized annular permanent magnet itself, which is constructed by arranging small pieces in an annular shape with their ends touching each other. Further, the permanent magnet obtained by the method of the present invention is extremely suitable as a permanent magnet for arc rotation in a rotary magnetic blowing type electric switch.

(Examples) Other advantages and features of the present invention will be made clearer by detailed description of examples along with the accompanying drawings in which examples are shown, but the present invention is not limited only to these examples. It's not something you can do.

FIG. 1 is a simplified cross-sectional view showing a contact of an electric switch equipped with a magnetically blown permanent magnet according to the present invention, FIG. 2 is a cross-sectional view taken along line T in FIG. A simplified perspective view of a permanent magnet in the middle of winding, FIG. 4 is a sectional view showing another embodiment in the same manner as FIG. 2, and FIG. 6 is a perspective view showing a small piece of a magnet, FIG. 6 is a sectional view showing yet another embodiment similar to FIG. 2, and FIG. 7 is a permanent magnet used in the embodiment shown in FIG. 6. FIG. 8 is a perspective view showing a small piece similar to FIG. 5, and FIG. 8 is a plan view showing a method of manufacturing the small piece of FIG.

FIG. 1 shows the arc contact 10.12 of the switch disclosed in the above-mentioned Fuchns patent specification. A permanent magnet 14 is placed inside one of the arc contacts 12. The permanent magnet 1 is annular or hollow cylindrical.
4 is fixed to the front end face portion of the arc contact 12, and is magnetized in the radial direction so as to generate a magnetic field that crosses between the arc contacts 10 and 12, as indicated by the arrow in the figure. There is. In the embodiments shown in FIGS. 2 and 6, the permanent magnet 14 is made of a flexible material, so that it is rolled into a cage 16 fitted behind and inside the arc contact 12 to form an annular shape. It can be done. A small diameter portion of the cage 18 may be fitted into the hole inside the permanent magnet 14 to hold the permanent magnet and at the same time protect it from the action of the arc. Permanent magnet 14
For example, it is made by molding cobalt samarium powder together with elastomer. In this case, a rectangular strip-shaped piece with a cross section mt- corresponding to the cross-sectional area of the permanent magnet 14 is compression molded in a transverse magnetic field, and then this molded powder is sintered, which is anisotropic. The method is the same as the method for manufacturing permanent magnets in general. This material, especially compression-molded elastomers, has the property of being flexible or deformable, so it can be magnetized in the radial direction by winding up a broken strip as shown in Figure 6. It becomes possible to realize an annular permanent magnet 14 that has a similar shape.

When flexibility is required, there are naturally restrictions on the selection of materials for making the permanent magnet 14, but
The other embodiments shown in FIGS. 4 and 5 overcome that limitation.

That is, the permanent magnet shown in FIG.
．． 22 and 24 are in contact at their respective ends.

Each small piece has the same shape and forms part of an annular shape, and both ends are formed by surfaces parallel to the radial direction. small piece 2
0.22.24 are made from powder by the method described above and are penetrated in the transverse direction, and these are placed in the holding cage 1 (S, 1
8 and forms a radially magnetized annular permanent magnet. The gaps between adjacent pieces 20, 22, 24 are extremely small and have no effect on the radial field strength. There are no difficulties in the manufacture of the pieces 20, 22, 24, and their expanded shape makes it possible to apply pressure forces and magnetic fields.

A third embodiment of an annular, more precisely hexagonal, permanent magnet 14 is shown in FIGS. 6-8.

In this embodiment, the small pieces are hexahedral, and six pieces of the same shape are combined to form a permanent magnet 14t. These small pieces 26 to 66 come into contact with each other to form an annular contact surface 68.
The ends are cut diagonally to form a .

These contact surfaces 68 all extend in the radial direction.

9- Not only do the hexahedral small pieces 26 to 56 all have the same shape, but also the faces facing each other in the transverse direction are flat, making manufacturing and magnetization easier.

Each small piece can be manufactured from the beginning in the desired shape of a trapezoid, but it is also possible to first form a parallelepiped bar and cut the end obliquely to form the contact surface 68, as shown in FIG. .

The pieces 26-56 abut each other to form a regular hexagon and are held by the cage 16.18. In order to obtain a permanent magnet that is more nearly annular, the number of contact surfaces, that is, the number of small pieces, may be increased beyond six, and the pieces may be held by any known method other than the illustrated embodiment. The good news is also obvious.

Fourth, the strips can, for example, be glued together to form a radially magnetized integral part.

When using the manufacturing method shown in FIGS. 6 to 8 to make permanent magnets of various different dimensions, it is sufficient to change the dimensions of the constituent pieces.

The manufacturing method according to the present invention as described above is particularly suitable for manufacturing hetero-10-tropic magnets from powder.
It is clear that it may also be applied to other types of magnets.

(Effects of the Invention) The present invention has the effect of providing a method for manufacturing a radially magnetized annular permanent magnet by extremely simple means without requiring special equipment or the skills of a high-class concubine.

[Brief explanation of the drawing]

1 is a simplified cross-sectional view of a contact of an electrical switch having a magnetically blown permanent magnet according to the invention; FIG. 2 is a cross-sectional view taken along line I-1 in FIG. 1; FIG. is a simplified perspective view of a permanent magnet in the middle of winding, FIG. 4 is a sectional view showing another embodiment in the same manner as FIG. 2, and FIG. 5 is a diagram showing the embodiment shown in FIG. FIG. 6 is a sectional view showing a further embodiment similar to FIG. 2, and FIG. 7 is a perspective view showing a small piece of a permanent magnet used in the embodiment shown in FIG. 5 is a perspective view showing a small piece of the permanent magnet used, and FIG. 8 is a plan view showing a method of manufacturing the small piece of FIG. 7. 14: Annular permanent magnet 20, 22.24: Small piece 26, 28.30.32.34.66: Small piece 68: Contact surface Patent applicant Nissin Electric Co., Ltd. Representative Ue 1) Ku -

Claims (8)

[Claims] (1) A magnet that is spread out and magnetized in the transverse direction is manufactured, and based on this spread out magnet, magnetization is performed in the radial direction and an annular shape is created. A method of manufacturing a magnetized annular permanent magnet. (2) A small piece that forms part of an annular shape is magnetized in the transverse direction, and each end of the core piece is brought into contact to form a closed ring shape, and it is magnetized in the radial direction. A method of manufacturing a radially magnetized annular permanent magnet according to claim 1. (3) The radius according to claim 2, wherein the small piece forming part of the annular shape is in the form of a part of a circular arc, and the end portion extends between planes in the radial direction. A method for manufacturing a circular permanent magnet magnetized in a direction. (4) The small piece forming part of the annular shape is hexahedral, and the end slope of the small piece extends within the radial plane of the annular body formed by combining the small pieces. A method of manufacturing a radially magnetized annular permanent magnet according to claim 2. (5) The small piece that forms part of the annular form shall be made of a hexahedral straight bar with parallel surfaces, magnetized in the transverse direction, and the slopes at both ends of the piece shall be formed by cutting. A method for manufacturing a radially magnetized annular permanent magnet according to claim 4. (6) The radially magnetized magnet according to any one of claims 2 to 5, wherein all the small pieces forming part of the annular shape have the same shape and dimensions. A method for manufacturing annular permanent magnets. (7) The small pieces forming part of the 3J-shaped form are anisotropic permanent particles made of agglomerated cobalt-samarium powder, which is obtained by press-molding the powder in an induced magnetic field and then sintering it. A method for manufacturing a radially magnetized annular permanent magnet according to any one of claims 2 to 6 regarding magnets. (8) The magnet is made of a flexible material, and is wound around the magnet to form a ring-shaped body magnetized in the radial direction. How to create permanent magnets.