PRODUCTION PROCESS FOR RING SHAPED RESIN BONDED MAGNET MEMBER

摘要

THERE IS PROVIDED A PROCESS OF PRODUCING A RING SHAPED RESIN BONDED MAGNETIC MEMBER BY MOLDING A FEED MIXTURE 24 WHICH CONTAINS A LUBRICANT AND A MAGNETIC POWDER COMPOSITE MADE OF MAGNETIC POWDER ANDA HEAT CURABLE RESIN COMPOSITIONS WHICH IS IN A SOLID STATE AT A ROOM TEMPERATURE. THE PROCESS IS CHARACTERIZED IN THAT (1) HEATING AN INNER PERIPHERAL SURFACE OF THE ANNULAR CAVITY 20 SO AS TO TRANSFER HEAT TO THE FEED MIXTURE 24 WHEREBY HEATING THE FEED MIXTURE TO A TEMPERATURE NOT LOWER THAN A SOFTENING TEMPERATURE AND BELOW A CURRING TEMPERATURE OF THE RESIN COMPOSITION, AND COMPRESSING THE FILLED FEED MIXTURE AFTER OR DURING THE HEATING; AND (II) COOLING THE INNER PERIPHERAL SURFACE SO AS TO TRANSFER HEAT FROM THE HEATED AND COMPRESSED FEED MIXTURE THROUGH THE INNER PERIPHERAL SURFACE, WHEREBY COOLING THE FEED MIXTURE TO A TEMPERATURE BELOW THE SOFTENING TEMPERATURE OF THE RESIN COMPOSITION SO AS TO OBTAIN A GREEN COMPACT HAVING A RING SHAPE.