| 摘要 |
PURPOSE:To facilitate multipolar magnetization of a high coercive force magnet, and to realize high magnetic flux density inside of a resin-bonded rare-earth cobalt magnet when the device is to be injection molded by a method wherein thickness of the magnet is made to be specified value or less. CONSTITUTION:Thickness of a resin-bonded rare-earth cobalt magnet is made to 0.8mm. or less as to enable to perform easily multipolar magnetization of the magnet to be manufactured according to the injection molding method. For example, a material obtained by kneading R2TM17 magnetic powder of 60vol% and nylon 6 of 40vol% is made as raw material, a radially anisotropic magnet of 18mm. outer diameter, 5mm. height, 0.5 or 0.8mm. thickness is manufactured according to the magnetic field injection molding method, and is magnetized to 24 poles by a pulse magnetizer. The reason why thickness is limited to 0.8mm. or less is because width per one pole required for the present magnet is 2mm. or less, and moreover coercive force of the magnet is 7KOe or more, and sufficient magnetization can not be attained when thickness is not made to 1/3 or less even at the lowest. |
