Production of anisotropic resin magnet

Abstract

Abstract PURPOSE:To improve use life of a metal mold and enhance magnetic properties of a product with a small magnetomotive force by a method wherein a metal mold having a core of ferromagnetic material and a non-magnetic plate thicker than a product is used for the production of an anisotropic resin magnet by injection molding in a magnetic field. CONSTITUTION:A lower mold plate 2 of an injection molding machine is fitted with an electromagnet 3 and a magnetic pole 4, on which is fixed a metal mold consisting of ferromagnetic mold plates 8-10,12,13 and a non-magnetic mold plate 11. The plate 11 to constitute a product portion is set thicker than a product cavity, and the metal mold is provided therein with a core 16 of ferromagnetic material having a thickness corresponding to the increment of thickness. With a magnetic field developed in a cavity 6 by the electromagnet 3, a mixture of a magnet powder and a resin is injection molded to form a product. Wear of the plate 11 is reduced because the core 16 is applied with a part of the mold fastening force. Magnetic properties of the product magnet can be improved because the magnetic field in the cavity can be strengthened.

Inventors

• 👤 Takeshi Anpo
• 👤 Takahiro Motone

Bibliographic Details