Patent ID: 7779533
Filing Date: 2010-08-24
Classification: G08B,H01F,Y10T

Abstract:
1. A process for fabricating a sequence of non-deactivatable magneto-mechanical EAS markers, each marker having a marker resonant frequency, the process comprising: a. forming a plurality of cavities along a web of cavity stock, each of said cavities having a substantially rectangular, prismatic shape open on a large side and a lip extending substantially around the periphery of said opening of said cavity; b. cutting elongated resonator strips sequentially from a supply of magnetostrictive amorphous metal alloy using a resonator strip cutter system, said resonator strips having a resonator strip cut length; c. extracting at least one of said resonator strips from said resonator strip cutter system using an extractor that imposes a force on said resonator strips that that directs them away from said resonator strip cutter system and into said cavities; d. disposing at least one of said resonator strips in each of said cavities to provide a magnetomechanical element of said marker; e. affixing a lid to said lip to close said cavity and contain said magnetomechanical element therewithin; f. supplying bias elements from a supply of hard or semi-hard magnetic material; g. fixedly disposing a said bias element on said lid in registration with said magnetomechanical element; h. activating at least a portion of said markers by magnetizing said bias elements, whereby said activated markers are armed to resonate at said marker resonant frequency; i. measuring said marker resonant frequency of each of the markers in a preselected sample portion of said sequence, the markers of said sample portion having been activated in step (h); j. adaptively controlling said resonator strip cut length for resonator strips incorporated in subsequently produced markers of said sequence, said resonator strip cut length being adjusted to an updated resonator strip cut length determined from a difference between said measured marker resonant frequencies and a preselected target resonant frequency, whereby said difference for said subsequently produced markers is reduced; and k. repeating steps (i) and (j) through the course of said fabrication.