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:
Aug. 31, 1993
Filed:
Jun. 21, 1990
Shigeyoshi Saito, Odawara, JP;
Yuji Hata, Odawara, JP;
Takuji Ogawa, Odawara, JP;
Jyousei Shimizu, Odawara, JP;
Tsuyoshi Takahashi, Odawara, JP;
Masahiko Sega, Hiratuka, JP;
Kazuo Ono, Odawara, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A method of recording a servo signal on each track of a magnetic disk includes a first signal for demagnetizing the magnetic disk and a second signal for forming the servo signal. The recording width (core width) of the magnetic head is made greater than the width of the track. Parts for recording signals and not recording signals are set in each track. The first and second signals are selected and recorded in the signal recording part, thereby to form the servo signal. Current to be conducted to the magnetic head is cut in the part for not recording signals, and the track is skipped to the next part for recording signals. When the recording of the track has ended, the magnetic head is moved to the next track, and the above steps are repeated.