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:
Dec. 04, 1979
Filed:
Sep. 26, 1977
Geoffrey Bate, Boulder County, CO (US);
Larry P Dunn, Boulder County, CO (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A permanent magnet orients magnetic particles on a tape in a desired direction along the tape length (or, by rotating the magnet structure, at any desired angle to the tape length) while the tape moves past the magnet's gap. The magnet's poles are asymmetric about a time drawn through the gap center and perpendicular to the medium to first present an unfocused low intensity magnetic field to the tape followed by a narrowly focused high intensity field in the opposite direction, which latter field aligns a large proportion of the particles along desired parallel lines. Antennae attached to the pole pieces dissipate any additional undesired fields which might adversely affect the particle alignment achieved by the high intensity field.