Optimal fluid dynamic bearing for use in spindle motor, has radial bearings arranged at distances in platform, where bearing includes parameter relating to shaft diameter, bearing length and load factor for determining bearing friction loss

摘要

The bearing has a shaft (16) rotatably mounted on a bearing hole of a bearing bush (14) around a rotational axis (24) and includes a diameter (D-shaft). The shaft includes a hard platform (38) that runs perpendicular to the axis, and a bearing gap (20) runs between upper surfaces of the hole and shaft. A set of radial bearings (18a, 18b) includes a bearing length (L-URB), and is arranged at certain distances (L-lower, L-upper) in the platform, where the bearing includes a friction parameter relating to the shaft diameter, bearing length and load factor for determining bearing friction loss. An independent claim is also included for a spindle motor for driving a storage disk drive, comprising a stator.