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:
Feb. 20, 1979
Filed:
Mar. 30, 1977
Applicant:
Inventor:
Naohiro Hanaoka, Hachioji, JP;
Assignee:
Olympus Optical Co., Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
360118 ;
Abstract
An erase head comprises a magnetizable material which can be magnetized into a permanent magnet having N- and S-poles. The magnetization takes place in a manner such that one of the poles which is the first to be contacted by a magnetic medium to be erased is magnetized to produce a field strength which is less than the magnetic field strength produced by the other pole.