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. 24, 1989
Filed:
Sep. 08, 1987
Applicant:
Inventors:
Jun Ide, Furukawa, JP;
Tomoo Iizumi, Furukawa, JP;
Assignee:
Alps Electric Co., Ltd., , JP;
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B / ; G11B / ;
U.S. Cl.
CPC ...
360 7813 ; 360 75 ; 318696 ;
Abstract
A magnetic disk drive device includes a rotatable disk. The disk has at least data tracks and guard band tracks. The data is previously recorded on the data tracks in the reversed magnetization form, whereas no data is recorded on the guard band track. While the magnetic head seeks the data from the tracks, the data is detected at first from the data track. This position where the first data is detected is recognized as a zero track. The magnetic head data seeking is performed based upon this zero track which is electronically detectable.