Brushless motor, and disk drive equipped with the same

A brushless motor comprising:

• a rotor rotatable about a rotation axis and including a shaft centered on the rotation axis;
• a turntable in a generally disk shape mounted directly or indirectly to the shaft and allowing a disk with a mounting hole formed at its center to be mounted thereonto;
• and a rotor magnet rotating integrally with the turntable and the shaft;
• a bearing supporting the shaft in a rotatable manner;
• a housing having a tube portion with an inner peripheral surface onto which the bearing is fixed;
• and
• a stator facing the rotor magnet with a space therebetween and generating a rotational magnetic field, wherein
• the housing has, on an upper and outer surface of the tube portion, a retaining claw projecting radially outwards,
• the turntable has a central concave portion in a concave shape opened axially downwards, the central concave portion housing at least an upper end of the tube portion,
• the turntable is attached with a retaining member radially outside the central concave portion,
• the retaining member includes:
• a mounting base attached to the turntable;
• and
• a plurality of retaining pieces arranged axially below the retaining claw and projecting radially inwards from a radially outer end of the retaining claw in a state where the rotor is mounted onto the housing,
• when the rotor is mounted onto the housing, due to contact between the plurality of retaining pieces and the retaining claw, outer peripheral portions of the plurality of retaining pieces are inclined axially downwards and inner peripheral portions of the plurality of retaining pieces in contact with the retaining claw are inclined axially upwards, and
• when the rotor moves axially upwards with respect to the housing and the plurality of retaining pieces contact the retaining claw, contact between the outer peripheral portions of the plurality of retaining pieces and the turntable restricts axially downward inclination of the inner peripheral portions of the plurality of retaining pieces.