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:
Nov. 28, 1989
Filed:
Dec. 28, 1988
Applicant:
Inventor:
Jun Ide, Furukawa, JP;
Assignee:
Alps Electric Co., Ltd., , JP;
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B / ; G11B / ;
U.S. Cl.
CPC ...
360 7814 ; 360 7708 ; 360 7808 ; 360 7813 ; 360 75 ; 318685 ;
Abstract
A method for restoring the head to the track 0 in a disk drive unit which utilizes a stepping motor to position the head, the method comprising positioning the head to a position outside track 0 by exciting the stepping motor; returning the head thereafter toward an inner side to detect a position where the track 0 is found wihin a cycle of an excitation phase of the stepping motor; positioning the head at a position separated from the outer-most track 0 by a preset number of steps; and then controlling a current ratio to effect an excitation on a preset excitation phase, thereby positioning the head to the position over the track 0.