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:
Mar. 22, 1994
Filed:
Oct. 19, 1992
Takashi Kawabe, Hitachi, JP;
Moriaki Fuyama, Hitachi, JP;
Shinji Narishige, Mito, JP;
Masatoshi Tsuchiya, Hitachi, JP;
Eiji Ashida, Hitachiota, JP;
Makoto Morijiri, Hitachi, JP;
Hideki Yamazaki, Hitachi, JP;
Yutaka Sugita, Tokorozawa, JP;
Hiroshi Fukui, Hitachi, JP;
Tadayuki Iwakura, Hitachi, JP;
Makoto Aihara, Hitachi, JP;
Makoto Saito, Tokyo, JP;
Shunichiro Kuwatsuka, Odawara, JP;
Hiroshi Ikeda, Odawara, JP;
Yokuo Saitoh, Kanagawa, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A magnetic disc apparatus includes a magnetic disc for recording information; a thin film magnetic head including a magnetic pole structure having an upper magnetic pole tip and a lower magnetic pole tip arranged to provide a magnetic gap at respective end portions thereof for writing and reading information in and from the magnetic disc; a device for rotating the magnetic disc; and a device for positioning the thin film magnetic head; the upper and lower magnetic pole tips having different contours at the respective end portions as viewed from a side confronting the magnetic disc wherein the difference (.DELTA.CW in .mu.m) in the width, along the magnetic gap, of the upper magnetic pole tip and the width, along the magnetic gap, of the lower magnetic pole tip satisfies the relation