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. 07, 1994
Filed:
May. 04, 1992
Kanji Wakabayashi, Kyoto, JP;
Hironori Tomita, Katano, JP;
Tohru Nakamura, Katano, JP;
Noboru Kikuchi, Hirakata, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A lens drive device for an optical information recording and/or reproducing head, which has a cylindrical lens holder for the support of an objective lens assembly and a tubular guide bearing receiving the lens holder for sliding and rotary motions in a direction parallel to and about the longitudinal axis of the lens holder. The device also has magnetic yokes positioned on respective sides of the guide bearing and each having tracking and focusing coils wound therearound. The lens holder has two permanent magnets embedded therein with their respective different poles exposed radially outwardly from a peripheral surface of the lens holder. The guide bearing has two windows defined therein at respective locations corresponding to the respective positions of the permanent magnets in the lens holder. When the focusing coils on the respective yokes are energized, the lens holder can be driven in a focusing direction parallel to the longitudinal axis of the lens holder, while when the tracking coils on the respective yokes are energized, the lens holder can be driven in a tracking direction generally perpendicular to the longitudinal axis of the lens holder.