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:
Oct. 13, 1987
Filed:
Jun. 19, 1985
Takamichi Fuke, Furukawa, JP;
Chiaki Aikawa, Furukawa, JP;
Takashi Watanabe, Furukawa, JP;
Yuichi Hishi, Miyagi, JP;
Alps Electric Co., Ltd., , JP;
Abstract
A disk recording-reproducing device having a carriage with a read/write head, a screw shaft to shift the carriage with an engaging element through coupling between a spiral groove of the screw shaft and the engaging element, and a stepping motor to rotate the screw shaft. The spiral groove is composed of a number of groove portions each with a straight bottom whose angle of lead is substantially zero degree that are displaced successively, circumferentially and axially. Preferably, the screw shaft has plane portions for its positioning, and a rotor of the stepping motor has magnetization points being set correspondingly to the lines of the groove portions.