Patent ID: 6252319
Filing Date: 2001-06-26
Classification: G11B,H02K

Abstract:
A disk rotating mechanism comprisinga rotation shaft;a turntable which is mounted to the rotation shaft and on which a disc-shaped recording medium is placed;a spindle motor for rotating the rotation shaft, andautomatic aligning means for causing the center of gravity of a composite rotating body consisting of the rotation shaft, the turntable, the spindle motor, and the disc-shaped recording medium to be positioned in the rotation axis during rotation;wherein said automatic aligning means comprises a case body made of a non-magnetic material and formed as a flat cylinder with one end surface closed, a plurality of balance members freely moving in the inner space of the case body, and an attracting magnet attracting the balance members when the rotation is stopped, the closed end surface of the case body constituting the table portion of the turntable; whereinsaid automatic aligning means is provided in the outer periphery with respect to said spindle motor and wherein the case body is formed integrally with said rotor case of said spindle motor; and whereinthe inner peripheral surface of the case body of said automatic aligning means is formed as a round recessed surface; and whereinan inner peripheral surface formed as a recessed rounded surface of said outer periphery, and having a smaller curvature than that of said balance members enclosed in said movement space;so that when said balancing members are in contact with said recessed rounded surface, said balance members are also in point contact with each other.