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:
Sep. 27, 2005
Filed:
Feb. 06, 2003
Takahiro Inoue, Odawara, JP;
Kiyotada Itou, Odawara, JP;
Kazuhisa Shishida, Odawara, JP;
Shinji Matsushita, Odawara, JP;
Takao Horiguchi, Odawara, JP;
Takahiro Inoue, Odawara, JP;
Kiyotada Itou, Odawara, JP;
Kazuhisa Shishida, Odawara, JP;
Shinji Matsushita, Odawara, JP;
Takao Horiguchi, Odawara, JP;
Hitachi Global Storage Technologies Japan, Ltd., Odawara, JP;
Abstract
In a disk drive, since high-frequency repeatable runout (RRO) components own low correlative relationships between adjoining tracks, a servo control system of a magnetic head is followed to the high-frequency RRO components, and thus, in the worst case, there is a possibility that data which have been previously recorded on these tracks are destroyed. To avoid this problem, both a tracking type repetitive control unit which is followed to low-frequency RRO components, and a rejection type repetitive control unit which cancels the high-frequency RRO components are provided in a following control loop in order that the following control system is not unnecessarily followed to the high-frequency RRO.