JPH053115A - Multipolar magnetized permanent magnet - Google Patents

Abstract

PURPOSE:To obtain a small type cylindrical multipolar permanent magnet on which the number of poles in axial direction is increased. CONSTITUTION:The title multipolar magnetized permanent magnet is constituted in such a manner that a sector permanent magnet group 1c, which is formed by alternately adhering a sector permanent magnet 1a, which is magnetized in radial direction so that the bore side becomes N-pole and the outside diameter side becomes S-pole, and a sector permanent magnet 1b, which is magnetized in the direction opposite to the above, is formed into a cylindrical magnet 1d by joining the above-mentioned magnets together in such a manner that the adjacent magnetic poles in circumferential direction are the same pole or the different pole, and that the adjacent poles in axial direction (and circumferential direction) are different poles from each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-pole magnetized permanent magnet. More specifically, it relates to a cylindrical multi-pole magnetized permanent magnet in which adjacent magnetic poles in the axial direction have different polarities.

[0002]

2. Description of the Related Art As a cylindrical multi-pole magnetized permanent magnet in which adjacent magnetic poles in the axial direction have different polarities, those shown in FIG. 4 or FIG. 5 have been conventionally known.

In the structure shown in FIG. 4, the ring-shaped permanent magnet 3a is magnetized in the radial direction so that the inner diameter side is the N pole and the outer diameter side is the S pole, and conversely, the inner diameter side is the S pole and the outer diameter. By alternately bonding the ring-shaped permanent magnets 3b of the same size magnetized in the radial direction so that the side becomes the N pole, adjacent magnetic poles in the axial direction are formed in a cylindrical shape so as to be different poles from each other. The multi-pole magnetized permanent magnet 3c.

However, in such a cylindrical multi-pole magnetized permanent magnet, since a ring-shaped permanent magnet having a small diameter cannot be obtained due to the size limit of the magnetizing machine, the diameter of the magnet is eventually reduced. There is a problem that a cylindrical permanent magnet cannot be obtained.

Further, the one shown in FIG. 5 has N on the inner diameter side.
A ring in which poles and S poles are alternately magnetized, and the different poles are alternately magnetized on the outer diameter side corresponding to the poles so that adjacent magnetic poles in the circumferential direction are different from each other. -Shaped permanent magnets 4a and the same ring-shaped permanent magnets 4b whose circumferential positions are shifted so that adjacent magnetic poles in the axial direction are different poles from each other are alternately adhered to form a cylindrical multi-pole attachment. It is a magnetic permanent magnet 4c.

However, in such a cylindrical multi-pole magnetized permanent magnet, the thickness of the ring-shaped permanent magnet cannot be reduced so much due to the limit of strength, so that the thickness is always above a certain level. That is, unless the axial length of the cylindrical permanent magnet is increased, the number of bonded ring-shaped permanent magnets cannot be increased, in other words, the number of poles in the axial direction cannot be increased. ing.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a cylindrical multi-pole magnetized permanent magnet which is small in size and has an increased number of poles in the axial direction.

[0008]

The object of the present invention is as follows.
A fan shape in which a fan-shaped permanent magnet that is magnetized in the radial direction so that the inner diameter side is the N pole and the outer diameter side is the S pole and a fan-shaped permanent magnet that is magnetized in the opposite direction are alternately bonded in the axial direction. (1) A multi-pole magnetized permanent magnet formed by adhering the permanent magnet group in the circumferential direction so that adjacent magnetic poles in the axial direction have different polarities, or (2) magnetized in the opposite direction. This is achieved by a multi-pole magnetized permanent magnet that is alternately bonded in the circumferential direction with the formed fan-shaped permanent magnet group, and is formed into a cylindrical shape so that adjacent magnetic poles in the axial direction and the circumferential direction have different polarities. .

The mode (1) above is shown in FIG. That is, the fan-shaped permanent magnet 1a is magnetized in the radial direction so that the inner diameter side becomes the N pole and the outer diameter side becomes the S pole, and conversely, the inner diameter side becomes the S pole and the outer diameter side becomes the N pole in the radial direction. The magnetized fan-shaped permanent magnets 1b are alternately bonded in the axial direction to form a fan-shaped permanent magnet group 1c. In this fan-shaped permanent magnet group 1c, adjacent magnetic poles in the axial direction are different from each other. A plurality of them are adhered so that adjacent magnetic poles in the circumferential direction have the same polarity, and are formed into a cylindrical shape to form a multi-pole magnetized permanent magnet 1d.

Further, in the above-mentioned mode (2), the fan-shaped permanent magnets 2a and 2b similar to those in the case (1) are used, and the fan-shaped permanent magnets 2a and 2b are alternately bonded in the axial direction to bond them with the fan-shaped permanent magnet group 2c. To change the magnetic field to form a fan-shaped permanent magnet group 2d in a magnetized state. In these fan-shaped permanent magnet groups 2c and 2d, adjacent magnetic poles in the axial direction are different from each other, and when the fan-shaped permanent magnet group is formed of an odd number of fan-shaped permanent magnets. In the magnet groups 2c and 2d, the numbers of the magnets 2a and 2b are opposite. They are alternately bonded so that adjacent magnetic poles in the circumferential direction have different polarities, and are formed into a cylindrical shape.
Let be e.

The fan-shaped permanent magnets (groups) are bonded to each other by
Using a guide jig made of a non-magnetic material, the adhesive coated surfaces are adhered to each other and pressed from both sides.

The fan-shaped permanent magnets 1a, 1b and 2a, 2b used in the above (1) or (2) are, for example, as shown in FIG.
It is obtained by the method as shown in.

First, the unmagnetized cylindrical permanent magnet 1e is radially cut in the axial direction to form a plurality of fan-shaped objects 1f, 1f ', 1
f, ... After arranging these fan-shaped objects in close contact with each other so that the inner peripheral surface side 10 and the outer peripheral surface side 11 thereof are staggered, they are magnetized with an N pole and an S pole. It is installed between devices 14 and 15 and magnetized in the radial direction.

Thus, the fan-shaped article 1h is magnetized in the radial direction so that the inner diameter side is the N pole and the outer diameter side is the S pole.
And, conversely, a fan-shaped object 1i magnetized in the radial direction so that the inner diameter side is the S pole and the outer diameter side is the N pole,
By further cutting these in the radial direction, fan-shaped permanent magnets 1a (2a) and 1b (2b) are obtained.

Further, the fan-shaped objects 1f, 1f ', 1f, ...
.. can be individually magnetized in the radial direction without having the cutting surfaces closely arranged as described above.

[0016]

Industrial Applicability The fan-shaped permanent magnet magnetized in the radial direction is used as the minimum component, and it is possible to reduce the diameter and the thickness, and the magnetic poles adjacent to each other in the axial direction are different from each other. To form a fan-shaped permanent magnet group, and to form a multi-pole magnetized permanent magnet by bonding them in a cylindrical shape so that adjacent magnetic poles in the circumferential direction have the same or different poles. Since the obtained cylindrical multi-pole magnetized permanent magnet can have a small diameter by reducing the diameter and thickness of the fan-shaped permanent magnet, and the interval between the poles in the axial direction can be reduced, Even if the number of poles in the axial direction is increased, the length is not increased.

Further, such a cylindrical multi-pole magnetized permanent magnet is attached to the tip of a spinning nozzle and is effectively used for manufacturing a magnetic hollow fiber or the like.

[Brief description of drawings]

FIG. 1 is an explanatory diagram illustrating the order of a first aspect of the present invention.

FIG. 2 is an explanatory diagram that follows the order of the second aspect of the present invention.

FIG. 3 is an explanatory diagram for following a sequence for obtaining a fan-shaped permanent magnet used in each of the first and second aspects of the present invention.

FIG. 4 is an explanatory diagram that follows the order of one aspect of a known technique.

FIG. 5 is an explanatory diagram that sequentially follows another aspect of the known technique.

[Explanation of symbols]

1a Fan-shaped permanent magnet 1b Fan-shaped permanent magnet 1c Fan-shaped permanent magnet group 1d Cylindrical multi-pole magnetized permanent magnet 2a fan-shaped permanent magnet 2b fan-shaped permanent magnet 2c Fan-shaped permanent magnet group 2d fan-shaped permanent magnet group 2e Cylindrical multi-pole magnetized permanent magnet

Claims (4)

[Claims] 1. A fan-shaped permanent magnet magnetized in the radial direction so that the inner diameter side is the N pole and the outer diameter side is the S pole, and a fan-shaped permanent magnet magnetized in the opposite direction are alternately arranged in the axial direction. A multi-pole magnetized permanent magnet in which a group of bonded fan-shaped permanent magnets are bonded in the circumferential direction, and are formed in a cylindrical shape so that adjacent magnetic poles in the axial direction have different polarities. 2. A fan-shaped permanent magnet that is magnetized in the radial direction so that the inner diameter side is the N pole and the outer diameter side is the S pole, and a fan-shaped permanent magnet that is magnetized in the opposite direction are alternately arranged in the axial direction. The adhered fan-shaped permanent magnet groups are alternately adhered in the circumferential direction to the fan-shaped permanent magnet groups magnetized in the opposite direction, and the adjacent magnetic poles in the axial direction and the circumferential direction have different polarities. A multi-pole magnetized permanent magnet formed in a cylindrical shape. 3. An unmagnetized cylindrical permanent magnet is radially cut in the axial direction and divided into a plurality of fan-shaped objects, which are N poles on the inner diameter side and S poles on the outer diameter side, or the opposite. 2. A fan-shaped permanent magnet, which is N-pole on the inner diameter side and S-pole on the outer diameter side, and which is magnetized in the opposite direction. 2. The multi-pole magnetized permanent magnet according to 2. 4. A plurality of fan-shaped objects obtained by cutting an unmagnetized cylindrical permanent magnet radially in the axial direction so that the inner peripheral surface side and the outer peripheral surface side thereof are staggered. The multi-pole magnetized permanent magnet according to claim 3, wherein a sector-shaped permanent magnet is used, which is obtained by arranging the cutting surfaces in close contact with each other, magnetizing them in the radial direction, and further cutting them in the radial direction.