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:
May. 20, 1980
Filed:
Feb. 13, 1978
Jean L Guilgue, Vendome, FR;
Metalimphy, Paris, FR;
Abstract
A method for identifying an article provided with a coded magnetic member comprising creating a detection zone by supplying an exciter coil with exciting alternating current, passing the article with the coded magnetic member through the detection zone to produce at least one signal from the coded magnetic member and detecting the derived signal using a detector coil to determine the code of the magnetic member. The magnetic member is provided with at least one of a plurality of elements made of magnetic alloys each having a different hysteresis loop and a code value is assigned to each type of alloy. The code value of each of the elements is decoded by measuring the phase shift of the signal derived using the detector coil relative to the phase of the exciting alternating current. This phase shift is indicative of the type of alloy and of the code value assigned thereto.