JP2797754B2 - Magnetization method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetizing method.

[0002]

2. Description of the Related Art In a conventional magnetizing method, as is known as a magnetizing method of a permanent magnet, an electric charge is accumulated in a high-voltage and large-capacity capacitor, and a large current is applied to a coil wound around a soft magnetic yoke so that the magnet is magnetized. As is known as a method using a magnetized yoke for magnetizing or a method for magnetizing a magnetic drum or a magnetic disk, a floating magnetic head is brought close to a magnetic drum or a magnetic disk, which is a magnetic recording medium, and a gap portion of the floating magnetic head is used. A method of magnetizing a magnetic drum by generating a magnetic field has been used.

[0003]

However, in the case of magnetizing using a magnetizing yoke among the above-mentioned prior arts, even if a small-diameter and long magnetic material-containing member is to be magnetized at a fine pitch, it is magnetized. Since the coil wound on the yoke has a small diameter and a long length, it is difficult to secure an ampere turn required for magnetization. Particularly, when the minimum magnetization reversal pitch is 0.5 [mm] or less, the magnetic material-containing member may be damaged. Magnetization was extremely difficult. In addition, as a means for magnetizing the ferromagnetic layer at a fine pitch, it is easy to infer that a magnetic head such as that used in magnetic recording is used. It takes a long time to magnetize the member, which leads to an increase in the cost of the member containing the magnetic material, and the contact between the magnetic head and the ferromagnetic layer for a long period of time causes the magnetic head to crash, resulting in mass production. In addition, there is a problem that only low magnetization can be performed.

Accordingly, the present invention is to solve such a problem, and an object of the present invention is to provide a magnetization method capable of magnetizing a large area in a short time. Still another object is to provide a magnetizing method which is low cost, has high durability and is excellent in mass productivity. Still another object is to provide a magnetizing method capable of generating a sufficient magnetizing magnetic field even at a minute pitch. Still another object is to provide a small-sized and easy-to-handle magnetizing device using the magnetizing method of the present invention.

[0005]

A magnetizing method according to the present invention is a method for magnetizing a magnetic material-containing member having a ferromagnetic layer at least in the vicinity of a surface thereof, wherein the movable permanent magnet has at least a pair of N poles and S poles. A magnetic circuit member that forms a magnetic circuit extending from the N pole to the S pole; and a gap disposed in the magnetic circuit member, and moving the movable permanent magnet member to form a gap in the magnetic circuit member. An alternate magnetic field is generated to magnetize the ferromagnetic layer to a plurality of poles while moving the magnetic material-containing member relative to the gap.

Further, the magnetization method of the present invention is characterized in that at least the ferromagnetic layer of the magnetic material-containing member is elastically deformable. Further, the magnetizing method of the present invention includes the steps of:
It is characterized by being magnetized at a magnetization pitch of 0 μm or less.

[0007]

According to the above configuration of the present invention, even if the magnetic material is long, the gap width of the gap portion of the magnetic circuit member can be increased to achieve a long magnetizing at one time. It is also possible to uniformly magnetize the magnetized object at a fine pitch according to the gap length of the gap part of the circuit member. Particularly for the magnetized pitch, control the relative movement speed of the movable permanent magnet member or the magnetized object By doing so, it is possible to magnetize at a desired magnetization pitch. In addition, the movable permanent magnet member is moved to generate an alternating magnetic field in the gap of the magnetic circuit member, and the magnetic substance-containing member can be relatively moved with the gap to magnetize the magnetized object to a plurality of poles, Energy required for magnetization can be reduced to save energy. Further, since the magnetic circuit member, the permanent magnet member, and the driving means have a basic configuration, a simple and inexpensive magnetizing device having a simple structure can be manufactured.

Further, according to the above configuration of the present invention, at least the ferromagnetic layer of the magnetic substance-containing member, which is the magnetic substance to be magnetized, has an elastically deformable thin plate shape, rubber shape, or belt shape. A stable contact state between the magnetic circuit member and the object to be magnetized is maintained, and a magnetic field sufficient to magnetize the ferromagnetic layer can be stably supplied even with a minute pitch magnetization.

Hereinafter, the present invention will be described in detail with reference to examples.

[0010]

FIG. 1 is a schematic view showing a magnetizing method according to an embodiment of the present invention. An elastic layer 11 is formed concentrically around a shaft 10 and a ferromagnetic layer 12 is formed on the elastic layer 11. The shaft 10, the elastic layer 11, and the ferromagnetic layer 12 constitute a magnetic substance-containing member 13, which is a material to be magnetized. On the other hand, a cylindrical movable permanent magnet member 14 having a plurality of magnetic poles (four pairs of N poles and S poles in FIG. 1) and a magnetic circuit extending from the N pole to the S pole of the movable permanent magnet member 14 are formed. The magnetizing device is constituted by a magnetic circuit member 15 having a gap portion 16 and the movable permanent magnet member 14 is moved to generate an alternating magnetic field in the gap portion of the magnetic circuit member. While the magnetic material-containing member 13 is in close proximity or close contact with the gap 16 of the magnetic circuit member 15, the magnetic material-containing member 13 and the movable permanent magnet member 14 are respectively rotated to generate an alternating magnetic field in the gap 16. The magnetic material-containing member 13 is magnetized by moving the magnetic material-containing member 13 relative to the gap 16. Here, the magnetic material containing member 13 is M
In the case of split magnetization at the poles, the rotation speed A [rpm] of the magnetic material containing member 13 and the rotation speed B [r] of the movable permanent magnet member 14
pm] and the number of magnetic poles C of the movable permanent magnet member 14,
Although it is set so as to satisfy M = B * C / A, the magnetic material-containing member 13 and the movable permanent magnet member 14 may be rotated in a stepwise manner at a constant speed. However, if the gap length of the gap portion 16 is equal to or less than the magnetization reversal pitch of the magnetic material-containing member 13, it is possible to uniformly magnetize the entire circumference of the magnetic material-containing member 13. By appropriately selecting the relative speed with respect to the movable permanent magnet member 14, a desired number of magnetic poles can be obtained. The gap width (in the direction perpendicular to the paper) of the gap portion 16 is not affected by inductance, unlike the case of a magnetized yoke or a magnetic head, and therefore depends on the length of the magnetic substance-containing member 13 which is a material to be magnetized. It can be long. Therefore, it is possible to magnetize at a fine pitch of about several tens [μm] using the magnetizing method as shown in FIG. For example, when the long magnetic material-containing member 13 having a small diameter of 20 [mm] and a length of 220 [mm] is magnetized, a length of 2 [mm] with a magnetization reversal pitch of 30 [μm] is obtained.
Magnetization could be divided into about 2100 poles in the circumferential direction over 20 [mm].

FIG. 2 is a schematic view showing a magnetizing method according to another embodiment of the present invention. The magnetic material-containing member 23 is obtained by forming a ferromagnetic layer 22 on a sheet-like substrate 21. On the other hand, a movable permanent magnet member 24 in which a plurality of magnets 28 (eight magnets in FIG. 2) are fixed on a soft magnetic back yoke 29, and a non-magnetic material disposed around the movable permanent magnet member 24. A fixed sleeve 27 having the above structure and a magnetic circuit member 25 which is disposed on the fixed sleeve 27 and forms a magnetic circuit extending from the N pole to the S pole of the movable permanent magnet member 24 and has a gap 26 in the magnetic circuit. The magnetic device is configured to move the movable permanent magnet member 24 to generate an alternating magnetic field in the gap of the magnetic circuit member. In a state where the magnetic material-containing member 23 is close to or in close contact with the gap 26 of the magnetic circuit member 25, the magnetic material-containing member 23 and the movable permanent magnet member 24
Are respectively moved or rotated to generate an alternating magnetic field in the gap 16 and the magnetic substance-containing member 23 is moved to the gap 2.
6, the magnetic material-containing member 23 can be magnetized, and several tens [μ]
[m] can be formed at a magnetization reversal pitch of about [m]. For example, a magnetic stripe can be formed at a magnetization reversal pitch of about 50 [μm] on a magnetic sheet having a ferromagnetic layer equivalent to A4 paper size.

FIG. 3 is a schematic view showing a magnetizing method according to still another embodiment of the present invention.
Ferromagnetic layer 3 made of thin rubber magnet on cylindrical substrate 31
2 is formed. On the other hand, a plurality of magnets 38 (FIG.
A permanent magnet member 34 in which two magnets are fixed on a soft magnetic back yoke 39, and a movable permanent magnet member 34.
Forming a magnetic circuit from the N pole to the S pole of the magnetic circuit member 35 having a gap 36 in the magnetic circuit, thereby forming a magnetizing device, and moving the movable permanent magnet member 34 to form a gap in the magnetic circuit member. To generate an alternating magnetic field. The magnetic material-containing member 33 and the movable permanent magnet member 34 are rotated or reciprocated, respectively, in a state where the magnetic material-containing member 33 is brought into close or close contact with the gap 36 of the magnetic circuit member 35 at a predetermined interval by the pressing member 37. The magnetic material-containing member 33 is magnetized by generating an alternating magnetic field in the gap 36 and moving the magnetic material-containing member 33 relative to the gap 36. With the configuration shown in FIG. 3, even a magnetic material-containing member having a hard surface such as a magnetic drum can be stably magnetized at a fine pitch. For example, when the magnetic material-containing member 13 formed of a barium ferrite resin bound magnet having a diameter of 32 [mm], a length of 10 [mm] and a ferromagnetic layer of 0.8 [mm] in thickness is magnetized. At a magnetization reversal pitch of 0.5 mm, about 200 poles could be magnetized in the circumferential direction.

In FIG. 1, a shaft 10 is made of a metal having high rigidity such as stainless steel or aluminum, or a resin having relatively high rigidity such as a resin mixed with fiber. Also, the elastic layer 11
Is made of natural rubber, silicone rubber, urethane rubber, butadiene rubber, chloroprene rubber, neoprene rubber, isoprene rubber, NBR, etc., and the elastic layer is used in the form of rubber, foam, sponge, etc. An elastomer containing a styrene resin, a vinyl chloride resin, a polyurethane resin, a polyethylene resin, a methacrylic resin, or the like can be used. The thickness of the elastic layer 11 is 500 [μm]
In this manner, contact magnetization can be performed by elastic deformation.

1 to 3, the ferromagnetic layers 12, 2
Known materials for magnetic recording materials and magnet materials can be used for Nos. 2 and 32. More specifically, Fe, Ni, C
a magnetic material containing at least one element of o, Mn, and Cr, for example, γ-Fe ₂ O ₃ , Ba-Fe, N
i-Co, Co-Cr, Mn-Al, or the like can be used, and can be formed by coating, plating, sputtering, or the like.
When the magnetic field generating layer is formed by dispersing the ferromagnetic layer in a resin, the flexibility can be improved.
When the thickness is reduced to [μm] or less, preferably around 10 [μm], sufficient flexibility for contact magnetization can be obtained. Similar magnetic materials can be used for the movable permanent magnet member 14 and the magnets 28 and 38, but higher magnetic flux densities can be obtained by using rare earth magnets.

1 to 3, the magnetic circuit member 15,
25, 35 and the back yokes 29, 39 are formed by using a soft magnetic material having high magnetic permeability, for example, pure iron, permalloy, permendur, silicon steel, or the like.
6, 26 and 36 can generate a higher leakage magnetic flux density. The gap lengths of the gaps 16, 26, and 36 are as follows:
An area smaller than 1 [mm], which is close to the limit of the magnetization pitch of the magnetized yoke, and larger than about 10 [μm], at which a sufficient leakage magnetic flux density and response speed can be obtained with a magnetic head, is preferable. Typically, 10 [μm] to 500 [μm]
[m].

In addition to the above-described embodiment, the structure of the magnetic substance-containing member, which is a magnetized object, is not limited to a cylindrical shape, but may be a thin plate shape or a belt shape. The desired magnetization pattern can be selected by adjusting the shape of the gap of the magnetic circuit member, the configuration of the magnetic circuit, or adjusting the relative movement direction between the magnetic material-containing member and the gap, and the like. In addition to the magnetization in which the N and S poles appear alternately in the circumferential or axial direction, various magnetizations such as the spiral in which the N and S poles appear alternately, the lattice-like magnetization, etc. It is possible. Further, the magnetization direction can be not only horizontal magnetization but also vertical magnetization by adopting a magnetic circuit configuration in which magnetic flux passes in the thickness direction of the ferromagnetic layer. Further, in FIGS. 1 to 3, arrows indicate the rotation direction or the movement direction of each member, but do not limit the present invention, and other descriptions do not limit the present invention.

Although the embodiments have been described above, the present invention is not limited to the above-described embodiments, but can be used to form a magnetic pattern of a position detecting device using a magnetic material, a magnetic field generating member of an electromagnetic driving device, and a conveyance using a magnetic force. It can be applied to devices and the like, in particular, an electrophotographic developing device using a magnetic developer, a cleaning device, a transport device, a magnetic encoder for detecting a minute position, a driving device (motor, etc.) using a magnetic force, a magnetic card It is advantageous if applied to the creation of a magnetic pattern or the like.

[0018]

As described above, according to the present invention, it is possible to uniformly magnetize a large-area magnetized object at a fine pitch in a short time, and to variably select the magnetization pitch. is there.
In addition, since a magnetic field is generated from the permanent magnet, no special device is required for generating the magnetic field, and an energy-saving, compact, and inexpensive magnetizing device can be provided.

Further, according to the above configuration of the present invention, by forming at least the ferromagnetic layer of the magnetic substance-containing member which is the magnetic substance to be elastically deformable, the magnetic circuit member and the magnetic substance can be formed. Is maintained, and a magnetic field sufficient to magnetize the ferromagnetic layer can be stably supplied even with a minute pitch of magnetization.

Therefore, according to the magnetizing method of the present invention, there is an excellent effect that it is possible to provide a magnetizing device which is small in cost, has high durability, is excellent in mass productivity, and is small and easy to handle.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a magnetizing method according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing a magnetizing method according to another embodiment of the present invention.

FIG. 3 is a schematic view showing a magnetizing method according to still another embodiment of the present invention.

[Explanation of symbols]

 12, 22, 32 Ferromagnetic layer 13, 23, 33 Magnetic substance-containing member 14, 24, 34 Movable permanent magnet member 15, 25, 35 Magnetic circuit member 16, 26, 36 Void portion

Claims (3)

(57) [Claims] 1. A method of magnetizing a magnetic material-containing member having a ferromagnetic layer at least near a surface, comprising:
A movable permanent magnet member having a pole and an S pole, a magnetic circuit member forming a magnetic circuit from the N pole to the S pole, and a gap disposed in the magnetic circuit member; Magnetizing the magnetic circuit member to generate an alternating magnetic field in a gap portion of the magnetic circuit member, and magnetizing the ferromagnetic layer to a plurality of poles while relatively moving the magnetic material-containing member with the gap portion. Method. 2. The magnetizing method according to claim 1, wherein at least the ferromagnetic layer of the magnetic material-containing member is elastically deformable. 3. The method according to claim 1, wherein the ferromagnetic layer has a thickness of 500 μm or less.
2. The magnetizing method according to claim 1, wherein the magnetizing is performed by a switch.
Law.