| 摘要 |
<p>While the high energy density acquisition of a magnet is effective for smaller size and weight of an outer rotor motor or a permanent magnet field type DC motor and an improvement in torque density, torque pulsation, armature reaction, or the like deteriorates. If slot-less (core-less) construction is used in order to eliminate the torque pulsation and the armature reaction, the magnetoresistance is increased in a motor magnetic circuit. In order to solve the problems, an annular magnet which opens in the direction opposite to the direction in which a U shaped segment created in a unidirectional magnet field opens is used to thereby obtain a continuously changing anisotropic distribution in the range of angles of 0 to 90 degrees with an inner periphery direction tangent line and energy density (BH)max = 160 to 186 kJ/m3,which is applied.</p> |
