Patent ID: 8446059

Claim:
A spindle motor for use with a storage disk drive apparatus, the spindle motor comprising: a stator unit; and a rotor unit supported to be rotatable about a central axis with respect to the stator unit; wherein the stator unit includes: a stator arranged around the central axis; a base portion including a through hole passing therethrough in a direction parallel or substantially parallel to the central axis, and arranged on a lower side of the rotor unit in the direction parallel or substantially parallel to the central axis; and a circuit board attached to a lower surface of the base portion, and including a connection portion to which a conductive wire from the stator is connected after passing through the through hole; the lower surface of the base portion includes: a central region centered on the central axis; a peripheral region arranged around the central region, and positioned at a level higher than a level of the central region in the direction parallel or substantially parallel to the central axis; and a recess portion arranged in the central region and recessed upwards; the connection portion of the circuit board is accommodated within the recess portion; the recess portion includes a protrusion arranged to protrude downwards from a bottom surface of the recess portion; and a position of a distal portion of the protrusion is located at a level higher than a position of a lowermost surface region of the central region and lower than a position of the bottom surface of the recess portion in the direction parallel or substantially parallel to the central axis.