PURPOSE: To obtain an easily magnetized permanent magnet having a high magnetic flux density, excellent mechanical strength and excellent assembling quality, by configuring the permanent magnet out of not less layers than two which are respectively the injection body layer made of a rare earth magnetic powder and a resin binder and a ferromagnetic substance layer.
CONSTITUTION: A magnetic substance ring 5 is engaged with a cavity part 8 of a metal mold 6, and after a magnetic field is applied to the metal mold 6, the molten liquid of nylon whereinto an Sm2CO17 based magnetic powder is highly filled is injected into the cavity part 8. The magnetic substance ring 5 is made of a ferromagnetic substance. While the ferromagnetic substance is classified into the easily magnetized material called soft magnetic material and the highly coersive force material called hard magnetic material, the soft magnetic material is used for the magnetic substance ring 5. After the molten liquid of nylon is injected into the cavity part 8, it is solidified in a cooled way, and an injection body 1 is formed. The injection body 1 and the magnetic substance ring 5 are fastened to each other. Subsequently, after the molded product is taken out from inside the metal mold 6, it is demagnetized, and thereafter, it is magnetized.
| JPH04313293 | MOLDING OF ELECTRONIC APPARATUS |
| JP4930793 | Composite container |
| JPS63109026 | FORMING MACHINE |
FUJIWARA MASATO
SHIMODA TATSUYA
| JP46024236A | ||||
| JPS56114309A | 1981-09-08 | |||
| JPS559587B2 | 1980-03-11 |