Spindle motor and disk drive device
AssigneeTokyo Parts Industrial Co., Ltd.
InventorMasahiro Nishidate
Life of this patent
Estimating the term…
Abstract
Problem: With a simple constitution, to cause a spindle motor rotor to be eccentric in a pickup moving direction and to improve axial run-out caused by clearance between a rotating shaft and bearing. Means for Solving the Problems: A magnetic cap 40 is attached to an end 7e of a bearing 7 of a spindle motor M so as to cover an end face 7f. A ceiling 41 of the magnetic cap 40 is an annular magnetic material in which a lid 40g and opposing face 40a protruding therefrom are continuous, and the opposing face 40a works with an annular magnet 13 attached to the rotor to generate an attraction force F that causes the rotor R to be eccentric. The opposing face 40a is formed so as to be linearly symmetrical with respect to the axis line Y, which is the pickup movement line.
Claims3
A spindle motor for rotatably driving a disk-shaped recording medium using a brushless motor, the spindle motor comprising a rotor on which is provided an annular magnet on a surface orthogonal with the rotating shaft at a position concentric with the rotating shaft, and a stator on which is provided a cylindrical bearing supporting the rotating shaft, wherein the annular magnetic has an annular part having the same radius as the rotor side end of the bearing, on the bearing rotor end side there is attached an annular magnetic material covering such end part and opposing the annular part, and the magnetic material is formed as a projection such that between the bearing end and annular portion of the annular magnet a portion thereof projects toward the annular magnet side.
A disk drive device comprising a spindle motor rotatably driving a disk-shaped recording medium using a brushless motor and a read head moving along a first axis line orthogonally intersecting the central axis of rotation of the spindle motor, wherein the spindle motor comprises a rotor on which is provided an annular magnet on a surface orthogonal with the rotating shaft at a position concentric with the rotating shaft, and a stator on which is provided a cylindrical bearing supporting the rotating shaft, the annular magnetic has an annular part having the same radius as the rotor side end of the bearing, on the bearing rotor end side there is attached an annular magnetic material covering such end part and opposing the annular part, the magnetic material is formed as a projection such that between the bearing end and annular portion of the annular magnet a portion thereof projects toward the annular magnet side, and this projection is orthogonal with the rotation axis line, and is formed to be symmetrical along the first axis line, which is parallel with the disk-shaped recording medium, and to be asymmetrical with respect to a second axis line that intersects the rotating axis line at right angles.
Dependencies are inferred from the claim text.