JPH04322413A - flexible permanent magnet - Google Patents

Abstract

PURPOSE:To obtain a permanent magnet having a large tensile strength and a magnetic force by inclusion, in addition to a long flexible main body of magnet, of a flexible line of magnet body buried within the main magnet body and extending in the longitudinal direction of the main magnet body or a covering material to cover the external surface of the main body of magnet. CONSTITUTION:A flexible permanent magnet 10 is formed in the shape of a round rod by a flexible long-length main body of magnet 12 which is formed in the long-length by a mixture of a permanent magnet material powder and flexible base material and a flexible line of magnet body 14 buried within the main body of magnet 12 and extending in the longitudinal direction thereof. The round rod type permanent magnet 10 may be used as a round rod type magnet magnetized in the diameter direction by magnetizing the permanent magnet material in the diameter direction. The permanent magnet 10 is formed as the line-shaped magnet or the permanent magnet 22 is provided with a covering material to have an enhanced tensile strength. Therefore, a magnetic force of a permanent magnet can be enhanced by increasing a ratio of contained permanent magnet material to the base material.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a long flexible permanent magnet made by mixing powdered permanent magnet material into a flexible base material such as rubber or soft synthetic resin and molding the mixture.

0002

[Prior Art] Powdered permanent magnet material is mixed into a flexible base material such as rubber or soft synthetic resin, the mixture is formed into a long piece by pressing, etc., and the permanent magnet material is magnetized. Elongated flexible permanent magnets are known.

[0003] However, this type of flexible permanent magnet generally has a large amount of powdered permanent magnet material mixed into the flexible base material, and therefore has low tensile strength and is easily broken. For this reason, conventionally, it is difficult to produce long flexible permanent magnets with small cross-sectional areas such as wires, rods, strings, ribbons, and sheets using extrusion molding machines. Further, even if such a long flexible permanent magnet can be manufactured, the flexible permanent magnet has low tensile strength and is easily broken. Furthermore, if the mixing ratio of the powdered permanent magnet material is reduced in order to increase the tensile strength of the flexible permanent magnet, the magnetic force of the permanent magnet will be reduced.

0004

SUMMARY OF THE INVENTION An object of the present invention is to increase both tensile strength and magnetic force.

[0005]

[Solution, action, effect] The flexible permanent magnet of the present invention has
In addition to a long flexible magnet body formed from a mixture of a powdered permanent magnet material and a flexible base material, a flexible magnet body is embedded in the magnet body and extends in the length direction of the magnet body. It includes a flexible linear body or a flexible non-magnetic covering covering the outer surface of the magnet main body.

According to the present invention, the tensile strength is increased by the linear body or the coated body, so even if the mixing ratio of the powdered permanent magnet material is increased, the tensile strength is high and it is difficult to break. Therefore, a permanent magnet with both high tensile strength and high magnetic force can be obtained. The permanent magnet material may be magnetized during molding of the flexible permanent magnet, or during actual use of the flexible permanent magnet.

The permanent magnet of the present invention may include only one of the linear body and the covering, or may include both. However, if the coating is provided, the powdery permanent magnet material present on the surface of the magnet body is surrounded by the coating body, so compared to conventional flexible permanent magnets in which the surface of the magnet body is not coated, The magnet has excellent water resistance, oil resistance, chemical resistance, abrasion resistance, etc.

As the flexible base material used in the present invention, synthetic rubber, natural rubber, soft synthetic resin, etc., which can be easily kneaded with the powdered permanent magnet material, can be used. In particular, the synthetic resin used as the flexible base material is preferably one that can be easily and inexpensively obtained in a form that can be easily kneaded with the powdered permanent magnet material, such as vinyl chloride resin.

The powdered permanent magnet material used in the present invention is preferably a magnet powder with high coercive force, such as ferrite magnet powder or rare earth metal magnet powder.

[0010] As the linear body used in the present invention, a long thread, string, ribbon, or flexible metal wire made of synthetic fibers, natural fibers, etc. can be used. On the other hand, as the material of the covering body, synthetic rubber, natural rubber, synthetic resin, cloth, etc. can be used. As the synthetic resin material for the covering, thermoplastic resins such as polyester resins, polyamide resins, polyurethane resins, polyolefin resins, vinyl chloride resins, fluororesins, vinyl acetate resins, etc. can be used.

The covering may be formed by directly forming a film layer on the outer surface of the main magnet, or by wrapping a cloth ribbon-like material or a synthetic resin film around the outer surface of the main magnet. It may also be formed by adhesion.

0012

[Example] First, an example of the flexible permanent magnet of the present invention will be described.

Referring to FIG. 1(A), a flexible permanent magnet 10 is made by mixing a powdered permanent magnet material and a flexible base material, and molding the mixture into a long length. With the flexible elongated magnet main body 12 and the flexible linear body 14 embedded within the magnet main body 12 and extending in the length direction of the magnet main body 12,
It is formed in the shape of a round bar.

Referring to FIG. 1(B), the flexible permanent magnet 16 is made by mixing powdered permanent magnet material and a flexible base material, and molding the mixture into a long length. With the flexible elongated magnet main body 18 and the flexible linear body 20 embedded within the magnet main body 18 and extending in the length direction of the magnet main body 18,
It is formed in the shape of a plate.

Referring to FIG. 1(C), the flexible permanent magnet 22 is made by mixing a powdered permanent magnet material and a flexible base material, and molding the mixture into a long length. It is formed in the shape of a round bar by a flexible magnet main body 24 and a flexible non-magnetic covering 26 that covers the outer surface of the magnet main body 24.

Referring to FIG. 1(D), the flexible permanent magnet 28 is made by mixing powdered permanent magnet material and a flexible base material, and molding the mixture into a long length. It is formed into a prismatic shape by a flexible magnet main body 30 and a flexible non-magnetic covering 32 that covers the outer surface of the magnet main body 30.

Referring to FIG. 1(E), the flexible permanent magnet 34 is made by mixing a powdered permanent magnet material and a flexible base material, and molding the mixture into a long length. A flexible magnet main body 36 , a flexible linear body 38 embedded in the magnet main body 36 and extending in the length direction of the magnet main body 36 , and a magnet main body 36
It is formed into a round bar shape by a flexible and non-magnetic covering 40 that covers the outer surface of the bar.

Referring to FIG. 1(F), the flexible permanent magnet 42 is made by mixing powdered permanent magnet material and a flexible base material, and molding the mixture into a long length. A flexible magnet main body 44 , a flexible linear body 46 embedded in the magnet main body 44 and extending in the length direction of the magnet main body 44 , and a magnet main body 44
It is formed into a prismatic shape by a flexible, non-magnetic covering 48 that covers the outer surface of the magnet.

The round bar-shaped permanent magnets 10, 22, and 34 are magnetized in the diametrical direction by magnetizing the permanent magnet material in the diametrical direction, for example, as shown in FIG. 1(G). It can be used as a round bar magnet. On the other hand, the plate-shaped or prismatic permanent magnets 16, 28, and 42 can be magnetized in the thickness direction by, for example, magnetizing one of them 16 in the thickness direction, as shown in FIG. 1(H). It can be used as a magnetic plate magnet or a prismatic magnet.

The tensile strength of the permanent magnets 10 and 16 is increased by the linear body, the permanent magnets 22 and 28 are increased by the coating, and the permanent magnets 34 and 42 are increased by the linear body and the coating. ing. Therefore, the ratio of the permanent magnet material to the base material can be increased, thereby making it possible to obtain a permanent magnet with a large magnetic force. Although one linear body may be buried within the magnet main body as in the illustrated example, it is preferable to embed a plurality of linear bodies within the magnet main body.

[0021] In the case of any of the permanent magnets, the above-mentioned materials can be used as the flexible base material, permanent magnet material, linear body, and covering body. In addition, when magnetizing the permanent magnet material, if rubber is used as a flexible base material, after vulcanization,
When using a synthetic resin, it is preferable to perform each step after curing. However, as described above, the permanent magnet material may be magnetized when the flexible permanent magnet is molded or when the flexible permanent magnet is actually used.

Next, an embodiment of the flexible permanent magnet manufacturing apparatus of the present invention will be described.

The manufacturing apparatus 50 shown in FIG. 2 uses a thermoplastic synthetic resin as a flexible base material and a linear body as a reinforcing material.

The mixture 52 of the synthetic resin and the unmagnetized powdery permanent magnet material is housed in an extruder 54 for thermoplastic synthetic resin, and the synthetic resin is molten in the extruder 54. It is continuously extruded from a crosshead type die 56. On the other hand, the linear body 58 is wound around a reel 60, is continuously supplied to the die 56 from behind, and is continuously extruded from the die 56 together with the mixture 52.

[0025] As a result, the mixture 52 and the linear body 58 are formed into a high-temperature elongated body having a predetermined cross-sectional shape, with the linear body 58 being embedded in the mixture 52. The elongated body extruded from the die 56 is passed through a cooling machine 62, a pulling machine 64, and a magnetizing machine 6.
6. It passes through a take-up machine 68 and is wound up by a wind-up machine 70. The extruded elongated body is moved by the extrusion force of the extruder 54, the suction force of the take-up machines 64 and 68, and the winding force of the winder 70.

In the moving process, the extruded high-temperature elongated body is first cooled to room temperature with water or the like in a cooler 62 to become a long flexible permanent magnet, and then in a magnetizer 66. By magnetizing the permanent magnet material, it becomes a magnetized elongated flexible permanent magnet.

The manufacturing apparatus 80 shown in FIG. 3 uses rubber as a flexible base material and a linear body as a reinforcing material. This manufacturing device 80 is a known extruder 8 for unvulcanized rubber.
A heating machine 84 for vulcanizing unvulcanized rubber is disposed between 2 and the cooling machine 62.

A mixture 86 of unvulcanized rubber and unmagnetized powdered permanent magnetic material is continuously extruded from a rubber crosshead die 88 of an extruder 82. On the other hand, the linear body 58 is continuously supplied from the reel 60 to the die 88 and is continuously extruded from the die 88 together with the mixture 86.

As a result, the mixture 86 and the linear body 58 are formed into an unvulcanized elongated body having a predetermined cross-sectional shape with the linear body 58 embedded in the mixture 86. The unvulcanized elongated body extruded from the extrusion port of the die 88 has its rubber component vulcanized in the heating machine 82, and then passes through the cooling machine 62, the take-off machine 64, the magnetizing machine 66, and the take-off machine 68. As a result, it is wound up by the winding machine 70 as a magnetized long flexible permanent magnet.

A manufacturing apparatus 90 shown in FIG. 4 forms a reinforcing covering made of thermoplastic synthetic resin on a molded long flexible magnet main body 92. Magnet body 92 can be produced, for example, in the apparatus of FIGS. 2 or 3 by not activating magnetizer 66 and is therefore not magnetized.

The synthetic resin 96 contained in the synthetic resin extruder 94 is continuously extruded in a molten state from a coating crosshead die 98 of the extruder 94. On the other hand, the magnet main body 92 is connected from the reel 100 to the heating machine 102.
The synthetic resin 96 is continuously supplied to a die 98 through the process, and is continuously extruded from the die 98 with a synthetic resin 96 coating formed thereon.

[0032] As a result, the magnet main body 92 and the synthetic resin 96
The magnet body 92 is formed into a long body having a predetermined cross-sectional shape and having a synthetic resin coating around the main body 92 of the magnet. The elongated body continuously extruded from the die 98 is passed through a cooling machine 62, a take-off machine 64,
By passing through a magnetizing machine 66 and a take-up machine 68, it is wound up by a winding machine 70 as a magnetized long flexible permanent magnet.

In the flexible permanent magnet manufactured by the manufacturing device 90, the magnet main body 92 itself is reinforced by a linear body embedded therein, and the outer peripheral surface of the magnet main body 92 is reinforced and protected by a covering. has been done. Also, the sheath is non-magnetic, so the magnetic circuit will not be shorted by the sheath.

The manufacturing apparatus 110 shown in FIG. 5 uses a thermoplastic synthetic resin as a flexible base material, and also molds the main part of the magnet and applies a reinforcing film made of the thermoplastic synthetic resin to the outer surface of the main part of the magnet. The formation of

A mixture 114 of thermoplastic synthetic resin and powdered permanent magnetic material is housed in an extruder 112 for synthetic resin.
is supplied from the extruder 112 to one socket of a two-layer extrusion die 116. In contrast, the reinforcing thermoplastic synthetic resin 1 housed in the synthetic resin extruder 118
20 is fed from the extruder 118 to the other receptacle of the die 116.

[0036] As a result, the mixture 114 and the synthetic resin 12
0 means that a high-temperature elongated body with a synthetic resin coating formed around a high-temperature magnet main body having a predetermined cross-sectional shape is the die 11.
It is continuously extruded from 6. The extruded elongated body is
It passes through a cooler 62, a take-up machine 64, a magnetizer 66, and a take-up machine 68, and then is wound up by a winder 70.

In the manufacturing apparatuses 90 and 110, when rubber is used instead of thermoplastic synthetic resin, an extruder for rubber is used instead of an extruder for synthetic resin, and the extruded long rubber A heating machine for vulcanizing the liquid may be placed before the cooling machine 62. In addition, if the flexible permanent magnet is not magnetized when molding the flexible permanent magnet, the above manufacturing apparatus 5
The magnetizer 66 at 0, 80, 90, and 110 may be deleted or the magnetizer 66 may not be operated.

The flexible permanent magnet of the present invention can not only be used in the same way as known flexible permanent magnets, such as sealing materials for the doors of electric refrigerators, but also can be used to attract and separate magnetic particles in liquids. It can be used as a magnet for attracting equipment, a guide magnet for transportation equipment that has a magnetic sensor, a magnet for displaying the magnetic material by cutting it to any length, adhering it to the surface of a magnetic material, etc. .

[Brief explanation of drawings]

FIG. 1 is a diagram showing an embodiment of a flexible permanent magnet of the present invention.

FIG. 2: First apparatus for manufacturing a flexible permanent magnet of the present invention.
It is a figure showing an example of.

FIG. 3: A second apparatus for manufacturing a flexible permanent magnet of the present invention.
It is a figure showing an example of.

FIG. 4: Third part of the apparatus for manufacturing a flexible permanent magnet of the present invention.
It is a figure showing an example of.

FIG. 5: A fourth apparatus for manufacturing a flexible permanent magnet of the present invention.
It is a figure showing an example of.

[Explanation of symbols]

10, 16, 22, 28, 34, 42 Flexible permanent magnet 12, 18, 24, 30, 36, 44 Magnet main body 1
4, 20, 38, 46 Linear body 26, 32, 40, 48 Covering body

Claims (3)

[Claims] Claim 1: A long flexible magnet body formed by molding a mixture of a powdered permanent magnet material and a flexible base material; A flexible permanent magnet comprising an elongated flexible linear body. 2. The flexible permanent magnet according to claim 1, further comprising a flexible and non-magnetic coating layer that covers the outer peripheral surface of the magnet main body. 3. A long flexible magnet body formed by molding a mixture of a powdered permanent magnet material and a flexible base material, and a flexible and non-magnetic coating that covers the outer surface of the magnet body. A flexible permanent magnet, including a body.