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. 29, 1993
Filed:
Jul. 16, 1990
Kanji Wakabayashi, Kyoto, JP;
Hironori Tomita, Katano, JP;
Tohru Nakamura, Katano, JP;
Noboru Kikuchi, Hirakata, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
From the start of descending of a disk-shaped recording medium in a direction of approaching an objective lens in the optical axis direction by a loading mechanism until it is set at a specified position with respect to a spindle motor, a DC current is supplied to an optical axis direction driving coil through an evading current feeding circuit in a direction for a movable part to depart from the disk-shaped recording medium, and the movable part is located at the remotest position from the disk-shaped recording medium due to an electromagnetic force generated by the DC current flowing in the optical axis direction driving coil and a permanent magnet, so that the disk-shaped recording medium and the objective lens will not collide against each other even if an objective lens with a short working distance is used.