发明名称 |
Radially anisotropic ring R-TM-B magnet, its production method, die for producing it, and rotor for brushless motor |
摘要 |
A method for producing a radially anisotropic ring magnet having at least one axial groove on the inner surface comprises using a die comprising a cylindrical, magnetic core, a magnetic sleeve having an axial ridge in alignment with the groove on the outer surface and disposed on an outer peripheral surface of the core, and an outer, cylindrical die member defining a cavity for forming the ring magnet with the magnetic sleeve, and compression-molding magnet powder charged into the cavity while applying a magnetic field in a radial direction, and a radially anisotropic ring magnet substantially having a composition of R-TM-B, wherein R is at least one of rare earth elements including Y, TM is at least one of transition metals, and B is boron, having at least one axial groove on the inner surface, and magnetized such that centerlines between magnetic poles do not overlap grooves. |
申请公布号 |
US8937419(B2) |
申请公布日期 |
2015.01.20 |
申请号 |
US200812666245 |
申请日期 |
2008.06.23 |
申请人 |
Hitachi Metals, Ltd. |
发明人 |
Hirai Nobuyuki;Natsumeda Mitsutoshi |
分类号 |
H02K21/12;H01F1/057;H02K15/16;H01F41/02;H02K1/27;H02K15/03;H01F7/02 |
主分类号 |
H02K21/12 |
代理机构 |
Sughrue Mion, PLLC |
代理人 |
Sughrue Mion, PLLC |
主权项 |
1. A method for producing a radially anisotropic ring magnet having at least one axial groove on the inner surface, comprising using a die comprising a cylindrical, magnetic core, a magnetic core sleeve having an axial ridge in alignment with said groove on the outer surface and disposed around said magnetic core, and an outer, cylindrical, magnetic die member defining a cavity for forming said radially anisotropic ring magnet with said magnetic core sleeve, and compression-molding magnet powder charged into said cavity while applying a magnetic field in a radial direction. |
地址 |
Tokyo JP |