JPS60930B2 - Manufacturing method for rolled magnets - Google Patents

Description

Detailed Description of the Invention The present invention changes the magnetic orientation between the magnetized poles by nearly 90 degrees, makes it possible to effectively utilize the flow of magnetic flux inside the magnet, and provides a roll-shaped magnet with a high magnetic flux density on the surface of the magnet. The present invention relates to a method of manufacturing a shaped magnet.

A conventional method for producing a roll-shaped magnet is to press-form ferrite powder and phosphorize it to obtain a roll-shaped magnet.

Roll-shaped magnets manufactured by such a method have the disadvantage that the shrinkage rate varies depending on the freezing conditions, it is difficult to obtain magnets with constant dimensions, and the shape is easily distorted.
In addition, the process is complex and easy to damage when handling.
This was also a significant disadvantage in terms of yield.

Furthermore, the magnetic flux density of the rolled magnet obtained by this method is as low as 1,100 to 1,150 Gauss, and the specific gravity is as large as 5.0, making it disadvantageous in terms of weight. This eliminates the drawbacks of

Hereinafter, one embodiment of the method for manufacturing a rolled magnet of the present invention will be described with reference to FIGS. 1 to 7.

First, as shown in Fig. 1, a mixture of scale-shaped ferrite particles 1 that have been subjected to magnetic anisotropy treatment and a soot material 2 of rubber or synthetic resin for bonding the ferrite particles 1 is placed between rotating rolls 3. through the sheet 4, and the ferrite particles 1
is oriented in the rolling direction of the sheet 4 to obtain an anisotropic sheet-like magnet material that exhibits ferromagnetism in the thickness direction A rather than the length direction B of the sheet 4, as shown in Figures 2a and b. . The thickness of this sheet 4 is 0.5 to 3. The magnetic orientation is uniform within the range of the enemy, 3. If it crosses the line, it becomes incomplete. As shown in FIG. 3, such a sheet 4 is wound around a cylindrical shaft 5, and the sheets are overlapped to obtain the required thickness.

Next, in accordance with the number of magnetic poles required to obtain the necessary magnetic field, from the outer direction, a jig 7 equipped with a cone-shaped protrusion 6 is moved in the radial direction at a position f that is the middle part of the magnetic poles, as shown in FIG. A pinch-shaped cut 8 is formed in the. This state is shown in FIG. When the smooth cut 8 is formed in this way, stress is applied to the ferrite particles 1 that are aligned in the circumferential direction along the sheet 4,
The magnetic orientation changes along the fusuma-like notch 8. Magnetization is
As shown in FIG. 6, when the magnetizing is done in alignment with the magnetic pole of the yoke IQ on the part 9 where the ferrite particles 1 are lined up along the circumferential direction, the magnetizing magnetic flux m is generated between the adjacent different poles. Since the magnetic flux can effectively flow inside and can also be used effectively on the magnetic surface and its intermediate part j, the case of the rolled magnet 11 in which the sheet 4 is simply wound around the shaft 5 shown in FIG. Compared to the fact that the effective magnetic flux ○ is only on the magnetic field surface, the surface magnetic flux density is increased, and a strong rolled magnet 12 can be obtained.

In addition, when the shaft 5 with the sheet 4 wound thereon is magnetized on the outer surface with a roll-shaped magnet used as a product, the magnetic flux density of the cut surface from the outside is 1100. ~1300 Gauss,
When magnetically applied to the inner face in a ring shape, the magnetic orientation is effective even if the shaft 5 is removed and a cut is made from the inner diameter face, and the magnetic flux density on the surface can also be made up to 1100 to 1300 Gauss.

Further, the surface magnetic flux density of the roll-shaped magnet 11 shown in FIG. 7, which was simply a rolled-up sheet 4, was 800 to 900 Gauss.

Furthermore, after applying the cut 8, by applying pressure from the outside of the roll to eliminate the gap formed by the cut 8, the leakage magnetic flux will be reduced, and the surface magnetic flux density will also be 1200~1
It can be increased up to 500 Gauss.

Although the notch 8 has been described as having a rectangular shape, any shape of the tip, such as not only a triangle but also a rectangular or semicircular shape, is effective for magnetic orientation and has almost the same effect. can be obtained.

As described above, according to the method for manufacturing a roll-shaped magnet of the present invention, when magnetizing on the same surface, effective magnetic flux flows throughout the magnet, so the surface magnetic flux density becomes high and the specific gravity becomes 3.5. The above-mentioned improvement in surface magnetic flux density enables weight reduction, and the use of composite magnetic materials makes it flexible and easy to process into any shape, making it easy to form both the inner and outer surfaces. It has many advantages, such as being magnetically visible and having a wide range of applications, and changing the orientation of the air after winding the sheet into a roll, making it easy to process and having little variation in processing. It is of great value.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram of the sheet manufacturing process showing an example of the method for manufacturing a rolled magnet of the present invention, and Figures 2a and b show the magnetic properties in the thickness direction and length direction of the sheet obtained by the same method. Figure 3 is a side view of the sheet winding process, Figure 4 is an explanatory diagram showing the notch forming process, Figure 5 is a side view of the sheet with the notch formed, and Figure 6 is the same serving process. A side view of the main parts of
FIG. 7 is a side view of the main part of the welding process of a roll magnet without notches. 1...Ferrite particles, 2...Medium 3...
...Roll "4... Sheet, 5... Shaft, 6...
...Protrusion, 7... Jig, 8... Cutting depth.
10... Magnetizing yoke, 12... Roll magnet. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7

Claims (1)

[Claims] 1 A mixture of ferrite particles and a medium bonding the ferrite particles is passed between rotating rolls, and a sheet in which the magnetically anisotropic ferrite particles in the medium are magnetically oriented in the rolling direction is wound into a roll, and then radiation A method for manufacturing a roll-shaped magnet characterized by forming notches in the direction and changing the magnetic orientation around the notches.