Method and apparatus for deactivating targets used in electromagnetic type article surveillance systems
First Claim
1. Apparatus for deactivating an electromagnetic article surveillance system target of the type comprising an elongated strip of magnetically soft, easily saturable magnetic material and an adjacent elongated strip of high coercivity, magnetically hard material, said apparatus comprising a solid element having a convexly curved outer surface and incorporating therein a plurality of permanent magnets arranged to produce in a plane adjacent said surface a pattern of variously directed magnetic fields such that along at least one given line in that plane, the magnetic fields are discontinuous, said curved outer surface of said solid element being rollable along a second surface and over a target affixed to said second surface.
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Accused Products
Abstract
A deactivator for deactivating targets used in electromagnetic article surveillance systems comprises a solid element with a convexly curved outer surface, e.g., a cylinder and a plurality of permanent magnets which form a patter of variously directed magnetic fields is a plane adjacent the surface. The curved surface of the deactivator is rolled over a target to be deactivated. The magnets are also arranged in adjacent layers with the magnets of one layer extending in a different direction from the magnets of the other layer to form a composite magnetic pattern which is discontinuous in all directions.
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Citations
16 Claims
- 1. Apparatus for deactivating an electromagnetic article surveillance system target of the type comprising an elongated strip of magnetically soft, easily saturable magnetic material and an adjacent elongated strip of high coercivity, magnetically hard material, said apparatus comprising a solid element having a convexly curved outer surface and incorporating therein a plurality of permanent magnets arranged to produce in a plane adjacent said surface a pattern of variously directed magnetic fields such that along at least one given line in that plane, the magnetic fields are discontinuous, said curved outer surface of said solid element being rollable along a second surface and over a target affixed to said second surface.
- 11. A method for deactivating an electromagnetic article surveillance system target of the type comprising an elongated strip of magnetically soft, easily saturable magnetic material and an adjacent elongated strip of high coercivity, magnetically hard material, said method comprising the steps of positioning, on a surface which contains a target, a solid element having a convexly curved outer surface and incorporating therein a plurality of permanent magnets arranged to produce, in a plane adjacent said curved outer surface, a pattern of variously directed magnetic fields such that along at least one given line in that plane the magnetic fields are discontinuous, and rolling said element along its said convexly curved outer surface and over the first mentioned surface in a manner such that said curved surface comes into contract with and thereafter moves away from said target.
- 14. A target deactivator for deactivating an electromagnetic article surveillance system target used of the type comprising a thin elongated strip of magnetically soft, easily saturated magnetic material and an adjacent elongated strip of high coercivity, magnetically hard low material, said target deactivator comprising a plurality of permanent magnets arranged so as to form in a continuous plane a pattern of magnetic fields which are discontinuous in every direction along said plane.
Specification