ROTARY APPARATUS

摘要

PROBLEM TO BE SOLVED: To provide a rotary apparatus capable of making inductance of an armature coil smaller while suppressing increase of driving current. ! SOLUTION: A rotary apparatus comprises: a rotor on which a recording disk should be mounted; and a solid body which supports the rotor freely rotatably via a bearing. The solid body includes: a stator core 40 including a plurality of salient poles 40b in radial directions; and multi-phase coils formed by being wound around the plurality of salient poles 40b. The rotor includes a cylindrical magnet which opposes to the salient poles 40b in radial directions and has a plurality of magnetic poles on a surface on the salient poles 40b side in a circumferential direction. The salient pole 40b includes: a base part 40c around which coil is wound; and a tip part 40d which is provided closer to the cylindrical magnet than the base part 40c and has portion bulged in circumferential directions from the base part 40c. The salient pole 40b is formed such that