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:
May. 31, 1994
Filed:
Mar. 30, 1992
Terumitsu Okamoto, Tokyo, JP;
Tomoaki Nakamura, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
A magnetic disk apparatus detects servo information on a magnetic disk which includes a plurality of concentric tracks which are provided with an alternate arrangement of data areas and servo areas. The apparatus includes a servo ID detecting circuit which generates a first detection signal when a servo area including an identification signal is detected and a data reproducing circuit which generates a second detection signal when read data pulses are detected on the signal reproduced from the magnetic disk. Sampling pulses are generated when the second detection signal indicates that the generation of read data pulses has terminated, while the first detection signal indicates the presence of the identification signal. The positional error of the magnetic head of the magnetic disk apparatus with respect to the target track of the magnetic disk is determined from the servo information of the signal reproduced from the magnetic disk in synchronism with the sampling pulses.