The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 08, 1993
Filed:
Jan. 29, 1991
Yoshio Chiba, Kanagawa, JP;
Sony Corporation, Tokyo, JP;
Abstract
A disc driving apparatus comprises a motor, a turntable which is rotated by a driving force of the motor and supports a disc on one side thereof, a fixed supporting portion for rotatably supporting the turntable, and magnetic means for always generating a predetermined magnetic attracting or repulsive force between the other side of the turntable and the fixed supporting portion which faces the other side of the turntable. A unidirectional urging force is always applied to the turntable by the magnetic means in the axial direction, so that even if an external vibration exists, when a force which is applied to the turntable by the vibration is equal to or less than the urging force, the turntable does not move in the axial direction. Thus, the interval between the disc supported on the turntable and a pickup does not change by the vibration, and an erroneous recording or reading of a signal can be avoided.