Production method of radial alignment type ring magnet mold and radial alignment type ring magnet

摘要

PROBLEM TO BE SOLVED: To provide a ring magnet molding die capable of suppressing the influence of a radial direction thickness at a recessed part and a projected part on the size of a radial orientation magnetic field and uniformizing the filling density of magnetic powder inside the ring magnet in the case of radial orientation magnetic field molding of a ring magnet provided with the recessed and projected parts on a peripheral surface.;SOLUTION: For the ring magnet molding die 2, a ring-like cavity 5 for supplying the magnetic powder is formed and the cavity 5 has the recessed and projected parts on its peripheral surface. The cavity 5 is formed of a cylindrical cavity formed by being surrounded by the ferromagnetic body 3a of a die 3 and a core 4 composed of the ferromagnetic body and the recessed and projected parts of a non-magnetic ring 3c composed of a non-magnetic body provided on the peripheral surface of the ferromagnetic body 3a inside the cavity.;COPYRIGHT: (C)2005,JPO&NCIPI