Patent ID: 8576512

Claim:
A spindle motor, comprising: a stationary unit; and a rotary unit supported to rotate about a center axis extending in an up-and-down direction; wherein the stationary unit includes a base member, an armature positioned above the base member, and a circuit substrate arranged on a lower surface of the base member and electrically connected to a coil of the armature; the rotary unit includes a magnet arranged in an opposing relationship with the armature; the base member includes a base groove portion arranged on the lower surface of the base member, at least one base through-hole extending through the base member from an upper surface of the base member toward the lower surface of the base member, and a first insulating sheet portion arranged on a bottom surface of the base groove portion; a lead wire extending from the coil is led out into the base groove portion through the base through-hole and connected to a land portion of the circuit substrate; and the base through-hole has a diameter which is different depending on the direction in which it extends, the base through-hole includes a major axis extending in a direction in which the diameter of the base through-hole becomes largest and a minor axis extending in a direction in which the diameter of the base through-hole becomes smallest, and the base through-hole includes a portion of an edge of the first insulating sheet portion arranged on the lower surface of the base member to intersect the major axis of the base through-hole and to cover a portion of the base through-hole.