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. 16, 1993
Filed:
Feb. 15, 1990
Applicant:
Inventor:
Samuel Montean, Blaine, MN (US);
Assignee:
Minnesota Mining and Manufacturing Company, Saint Paul, MN (US);
Primary Examiner:
Int. Cl.
CPC ...
H01F / ;
U.S. Cl.
CPC ...
335284 ; 335306 ; 340572 ;
Abstract
A multiple magnet assembly for magnetizing a magnetizable element of a desensitizable electromagnetic article surveillance marker, in which each successive assembly provides at a working surface a magnetic field of the same polarity but decreasing intensity. Any demagnetization effect attributable to reverse or back fields associated with one assembly are overcome by magnetization produced by a subsequent assembly, thus allowing markers having magnetizable elements with significantly different coercivee forces to be magnetized by the same apparatus.