EP0134404A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method and apparatus for target deactivation and reactivation
Assignee: Knogo Corp
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Filing: 1984-05-08
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Granted: —
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Expires: 2004-05-08
Abstract
Abstract Targets (14) mounted on objects (12) for detection by a magnetic type theft detection system are deactivated in a target deactivator (26) which has magnet assembly made up of spaced apart magnets with alternately opposed poles extending in a plane and guide walls (36, 38) extending perpendicular to the plane. Targets (14) are reactivated by a reactivator (46) having a magnet (52) mounted thereon and arranged to be slid along the target (14).
Inventors
- 👤 Michael N. Cooper
- 👤 Peter A. Pokalsky
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 06:44
CPC Classifications
G; G08; G08B; G08B13/00; G08B13/22; G08B13/24; G08B13/2402; G08B13/2405; G08B13/2408; G08B13/2411
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
146 words
A target deactivator (26, 64) for deactivating a target (14, 62) used in a magnetic type theft detection system, said target comprising a thin elongated strip (20) of magnetically soft, high permeability and easily saturable magnetic material and having laminated thereto a deactivation element (22) of magnetically hard, low permeability magnetic material, said target deactivator comprising a permanent magnet assembly (40, 72) made up of a plurality of permanent magnets (42, 72) lying in a flat plane with their poles arranged to form a line of spaced apart alternate north and south poles, support means (26, 66) for supporting said permanent magnet assembly and guide means (36, 38, 68, 70) for allowing relative movement of an object (12, 60) on which said target is mounted and said support means in a direction perpendicular to said flat plane while said target is maintained parallel to said plane.
Claim 2
Dependent Claim
146 words
A target deactivator (26, 64) for deactivating a target (14, 62) used in a magnetic type theft detection system, said target comprising a thin elongated strip (20) of magnetically soft, high permeability and easily saturable magnetic material and having laminated thereto a deactivation element (22) of magnetically hard, low permeability magnetic material, said target deactivator comprising a permanent magnet assembly (40, 72) made up of a plurality of permanent magnets (42, 72) lying in a flat plane with their poles arranged to form a line of spaced apart alternate north and south poles, support means (26, 66) for supporting said permanent magnet assembly and guide means (36, 38, 68, 70) for allowing relative movement of an object (12, 60) on which said target is mounted and said support means in a direction perpendicular to said flat plane while said target is maintained parallel to said plane.
Claim 3
Dependent Claim
50 words
A target deactivator according to claim 1 wherein said support means (26) is formed as the bottom surface (34) of a cavity in a housing (32) and said guide means is formed as the side walls (36, 38) of said cavity, said side walls extending perpendicular to said bottom surface.
Claim 4
Dependent Claim
37 words
A target deactivator according to claim 1 wherein said support means comprises a flat base (34, 36) and wherein said guide means comprises at least one wall (36, 38, 68, 70) extending perpendicularly up from said base.
Claim 5
Dependent Claim
34 words
A target deactivator according to claim 1 wherein said permanent magnet assembly (40, 72) comprises magnetic crystals oriented in a polymer binder and permanently magnetized with spaced apart alternate north and south magnetic poles.
Claim 6
Independent Claim
124 words
A method of deactivating a target (14, 62) used in a magnetic type theft detection system, said target comprising a thin elongated strip (20) of magnetically soft, high permeability and easily saturable material and having laminated thereto a deactivation element (22) of magnetically hard, low permeability magnetic material, said method comprising the steps of maintaining along a flat plane, a pattern of spaced apart alternate magnetic fields and, while maintaining said target and plane parallel to each other, moving one toward the other until said magnetic fields cause the formation of corresponding magnetic poles in said deactivation element and thereafter separating said deactivation element and said plane in a direction perpendicular thereto until the deactivation element is outside the influence of the magnetic fields.
Claim 7
Independent Claim
124 words
A method of deactivating a target (14, 62) used in a magnetic type theft detection system, said target comprising a thin elongated strip (20) of magnetically soft, high permeability and easily saturable material and having laminated thereto a deactivation element (22) of magnetically hard, low permeability magnetic material, said method comprising the steps of maintaining along a flat plane, a pattern of spaced apart alternate magnetic fields and, while maintaining said target and plane parallel to each other, moving one toward the other until said magnetic fields cause the formation of corresponding magnetic poles in said deactivation element and thereafter separating said deactivation element and said plane in a direction perpendicular thereto until the deactivation element is outside the influence of the magnetic fields.
Claim 8
Dependent Claim
28 words
A method of deactivating a target (14, 62) according to claim 5 wherein said target is moved toward said plane and thereafter is moved away from said plane.
Claim 9
Dependent Claim
33 words
A method of deactivating a target according to claim 5 wherein said target (14, 62) is mounted on an object (12, 60) and said object is moved toward and away from said plane.
Claim 10
Dependent Claim
94 words
A method of deactivating a target (14, 62) according to claim 5 wherein said target is mounted on one surface of a rectangular object (12, 60) and said spaced apart magnetic fields are maintained by permanent magnets (42, 72) arranged on a flat base (34, 66) adjacent a wall (36, 38, 68, 70) which extends perpendicular to said base and wherein said rectangular object is positioned against said wall with said target facing and extending along said magnets and is moved along said wall to move said target toward and away from said magnets.
Claim 11
Dependent Claim
147 words
A target reactivator (46, 76) for reactivating elongated magnetic targets (14, 62) used in theft detection systems and which have been deactivated by a pattern of spaced apart alternate magnetic fields emanating from a deactivation element (22) of magnetically hard low permeability material lying adjacent and extending continuously along the target and affixed with the target to an object (12, 60) being protected by the target, said reactivator comprising a magnet (52, 80) and a holder (46, 76) supporting said magnet, said holder being configured to be guided along said object in a direction along the length of the target with the poles of the magnet extending along the length of the target whereby the deactivation element become subjected to the field of said magnet and said pattern of spaced apart magnetic fields becomes erased by movement of said holder as it is guided along said object.
Claim 12
Dependent Claim
147 words
A target reactivator (46, 76) for reactivating elongated magnetic targets (14, 62) used in theft detection systems and which have been deactivated by a pattern of spaced apart alternate magnetic fields emanating from a deactivation element (22) of magnetically hard low permeability material lying adjacent and extending continuously along the target and affixed with the target to an object (12, 60) being protected by the target, said reactivator comprising a magnet (52, 80) and a holder (46, 76) supporting said magnet, said holder being configured to be guided along said object in a direction along the length of the target with the poles of the magnet extending along the length of the target whereby the deactivation element become subjected to the field of said magnet and said pattern of spaced apart magnetic fields becomes erased by movement of said holder as it is guided along said object.
Claim 13
Dependent Claim
28 words
A target reactivaor according to claim 9 wherein said magnet is a magnet assembly (52) having a plurality of spaced apart alternate magnetic poles extending in a plane.
Claim 14
Dependent Claim
63 words
ll. A target reactivator according to claim 9 wherein said holder comprises a U-shaped member (50) which fits over the bottom surface of a rectangular carton (12) and slides along the bottom surface (16) of the carton and wherein said magnet is mounted in the base of said member to slide along a target (14) mounted on said bottom surface of said carton.
Claim 15
Independent Claim
122 words
A method of reactivating an elongated magnetic target (14, 62) used in a theft detection system and which has been deactivated by a pattern of spaced apart alternate magnetic fields emanating from a deactivation element (22) of magnetically hard low permeability material lying adjacent the target and affixed with the target to an object (12, 60) being protected by the target, said method comprising the steps of positioning a magnet (52, 80) with its poles extending in a plane closely adjacent and parallel to the plane of the target so that the deactivation element is in the field of the magnet and moving the magnet along the target to erase the pattern of spaced apart alternate magnetic fields from said deactivation element.
Claim 16
Independent Claim
122 words
A method of reactivating an elongated magnetic target (14, 62) used in a theft detection system and which has been deactivated by a pattern of spaced apart alternate magnetic fields emanating from a deactivation element (22) of magnetically hard low permeability material lying adjacent the target and affixed with the target to an object (12, 60) being protected by the target, said method comprising the steps of positioning a magnet (52, 80) with its poles extending in a plane closely adjacent and parallel to the plane of the target so that the deactivation element is in the field of the magnet and moving the magnet along the target to erase the pattern of spaced apart alternate magnetic fields from said deactivation element.
Claim 17
Dependent Claim
43 words
A method of reactivating an elongated magnetic target according to claim 12 wherein said magnet is moved along the target by suppoting said magnet in a holder (50, 76) and guiding the holder along an edge of the object parallel to the target.
Claim 18
Dependent Claim
27 words
A method of reactivating an elongated magnetic target according to claim 13 wherein the poles of said magnet are maintained in a direction lengthwise of said target.
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