| 摘要 |
PROBLEM TO BE SOLVED: To improve a filing property, to minimize a quality variation and to reduce a cost for manufacturing by providing a magnet inside a central core of a mold. SOLUTION: A magnet 2 is provided inside a central core 1 of a mold which forms through holes for a core. A preserving box 3 for material powder is transferred just above a powder filing part of the mold. Then the bottom of the preserving box 3 is made in an opening state, the powder falls by own weight and is filed inside the mold. Next the central core 1 is elevated until all magnet including part is invaded in the preserving box 3 and the material powder made of magnetic powder is attached to the magnet including part of the central core 1. After that the central core 1 is descended to the original position and a predetermined volume of the material powder is mandatory supplied in the mold without forming bridges. Then the preserving box 3 is returned to the original position. Next, compression molding by vertically pressing by an upper punch 4 and a lower punch 5 is made while a magnetic field being impressed. By the means a filing property is improved and a quality variation of forms, sizes and so on is minimized.
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