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:
Jul. 07, 1992
Filed:
Jan. 16, 1990
Shigeki Koizumi, Yokoze, JP;
Hiroshi Oka, Chichibu, JP;
Canon Denshi Kabushiki Kaisha, Chichibu, JP;
Abstract
A disc drive unit for rotating a data storage disc such as an optical disc or a magnetic disc comprising a turntable for supporting and rotating the disc, and a motor for rotating the turntable. The turntable also functions as a rotor of the motor. At least one driving magnet is mounted on the turntable in opposing relationship with at least one coil of the motor. At least one attraction magnet for securely holding the disc in position on the turntable is securely mounted thereon. One yoke functions as yokes, each of which must be provided for each of two kinds of magnets. When the turntable is made of a plastic, at least one attraction magnet and/or at least one driving magnet is defined by partially magnetizing the turntable at at least one predetermined region thereof. The turntable is securely attached to the bearings so that it rotates about a shaft having one end securely fixed to a stationary portion of the motor. When rotating the disc, one of the bearings is used as a member for securely holding the disc in position on the turntable.