Patent ID: 7059771

Claim:
A motor with fluid dynamic pressure bearing comprising: a dynamic pressure bearing member; a rotary shaft that is rotatively supported by the dynamic pressure bearing; a rotary member that is joined to the rotary shaft, the rotary member is rotatively driven by electromagnetic drive force; an expanded diameter section that is provided on the dynamic pressure bearing member and is extended in a radial direction; a fallout preventing member that is provided on the rotary member and overlaps the expanded diameter section of the dynamic pressure bearing member in an axial direction to prevent the rotary shaft from falling out of the dynamic pressure bearing member; a concave section that is formed in a part of the rotary member and opposes one end surface of the expanded diameter section of the dynamic pressure bearing member in the axial direction; and an annular projection portion formed in a radially inner part of the concave section, projecting toward the other side in the axial direction and surrounding a rotary axis to form a bore where one end of the rotary shaft is fixed by joining an inner peripheral surface of the bore to an outer peripheral surface of the rotary shaft to form a joint section.