| 摘要 |
PURPOSE:To assure the stabilization of high magnetic performance and the enhancement of the mechanical strength by a method wherein the surface of a magnet is coated with a reinforcement layer comprising compound resin wherein the surface of a magnet layer is filled up with resin monomer or inorganic filler while the wall thickness of the layer is specified not to exceed 0.8mm. CONSTITUTION:Magnet powder or pure iron needle powder surface processed by a coupling agent and a resin are heated for kneading and then crushed respectively to make pellet A and pellet B. Then, the pellet A is heated in a cylinder 1a and the molten kneaded products 3a are driven by a screw 4a passing through strong magnetic pins 8 and a non-magnetic intermediate die 6 to be extruded into a strong magnetic die 7. The intermediate pins 8 and the die 7 are impressed with magnetic field (H indicates the impressed directions of magnetic field) by a coil 5 while the magnet powder arranges the magnetization accelerating axes radially in the radius direction. Simultaneously, the pellet B is heated in another cylinder 1b and the molten kneaded products 3b are extruded to coat the former molten kneaded products 3a so that an anisotropic magnet layer 11a and a reinforcement layer 11b may closely be solidified. Through these procedures, the stabilization of the magnetic performance and the enhancement of the mechanical strength can be assured thereby enabling the thin wall coating to be attained. |
