Patent US3601075A successfully refreshed from Google Patents.
Patent EP0446910A1 successfully refreshed from Google Patents.
EP0446910A1
Expired / Lapsed
EP
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Theft detection apparatus and flattened wire target and method of making same
Assignee: Knogo Corp
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Filing: 1991-03-13
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Granted: —
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Expires: 2011-03-13
Abstract
Abstract Items of merchandise are protected from shoplifting or theft by affixing to them special responder targets, which are formed by drawing a material of high magnetic permeability into a thin wire and thereafter rolling the wire into a flattened strip and annealing the strip and severing the strip into individual lengths. The flattened strip may be positioned on an adhesively coated base strip (42) and covered by a peel strip (50). Slug-like deactivation elements (48) of hard magnetic material may be positioned along the strip for deactivating it.
Inventors
- 👤 Peter Y. Zhou
- 👤 Thomas P. Solaski
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 07:24
CPC Classifications
G; G08; G08B; G08B13/00; G08B13/22; G08B13/24; G08B13/2402; G08B13/2405; G08B13/2408; G08B13/2411; G08B13/2428; G08B13/2437; G08B13/244; G08B13/2442; G11; G11B; G11B23/00; G11B23/02; G11B23/023; G11B33/00; G11B33/02; G11B33/04; G11B33/0405; G11B33/0488
Claims Analysis
Total Claims: 57
Claim 1
Independent Claim
94 words
A magnetic type electronic theft detection apparatus comprising means (14, 22) for generating an alternating magnetic interrogation field in an interrogation zone (19), means (16, 24) for detecting magnetic response fields having predetermined characteristics in said interrogation zone and responder targets (32) mounted on protected items (30) which must be carried through said interrogation zone when taken from a protected area, said responder targets each comprising an elongated strip (45) of an easily saturable magnetic material which has been pressed to change its cross-section and heat treated thereafter to substantially increase its magnetic permeability.
Claim 2
Dependent Claim
20 words
A magnetic type electronic theft detection apparatus according to claim 1, wherein said strip has been pressed by cold rolling.
Claim 3
Dependent Claim
26 words
A magnetic type electronic theft detection apparatus according to claim 2, wherein said strip has been rolled from a round cross-section to a flattened cross-section (62a).
Claim 4
Dependent Claim
30 words
A magnetic type electronic theft detection apparatus according to claim 1, wherein said strip has been maintained free of stresses in all directions other than in the direction of pressing.
Claim 5
Dependent Claim
34 words
A magnetic type electronic theft detection apparatus according to claim 4, wherein said easily saturable magnetic material from which said strip has been pressed is wire (62) which has been drawn and heat treated.
Claim 6
Dependent Claim
24 words
A magnetic type electronic theft detection apparatus according to claim 1, wherein said easily saturable material is a nickel-iron alloy containing about 80% nickel.
Claim 7
Dependent Claim
34 words
A magnetic type electronic theft detection apparatus according to claim 6, wherein said alloy contains one or more metals taken from the group consisting of copper, titanium, niobium, vanadium, molybdenum, chromium and mixtures thereof.
Claim 8
Dependent Claim
27 words
A magnetic type electronic theft detection apparatus according to claim 6, wherein said alloy contains from 2% to 8%, by total weight of the alloy, of copper.
Claim 9
Dependent Claim
25 words
A magnetic type electronic theft detection apparatus according to claim 6, wherein said alloy contains about 5% by total weight of the alloy, of copper.
Claim 10
Dependent Claim
18 words
A magnetic type electronic theft detection apparatus according to claim 6, wherein said alloy contains about 4% molybdenum.
Claim 11
Dependent Claim
21 words
A magnetic type electronic theft detection apparatus according to claim 4, wherein said easily saturable magnetic material is Permalloy wire (62).
Claim 12
Dependent Claim
45 words
A magnetic type electronic theft detection apparatus according to claim 11, wherein said flattened strip (62a) has been heat treated by annealing same at a temperature of at least 650 degrees Centigrade in an annealing atmosphere for a duration of at least one half hour.
Claim 13
Dependent Claim
44 words
A magnetic type electronic theft detection apparatus according to claim 11, wherein said flattened strip (62a) has been heat treated by annealing same at a temperature of at least 850 degrees Centigrade in an annealing atmosphere for a duration of at least one minute.
Claim 14
Dependent Claim
47 words
A magnetic type electronic theft detection apparatus according to claim 11, wherein said flattened strip (62a) has been heat treated by annealing same in an atmosphere consisting essentially of one of the group of dissociated ammonia, dry hydrogen, an inert gas, a mixture thereof and a vacuum.
Claim 15
Dependent Claim
34 words
A magnetic type electronic theft detection apparatus according to claim 4, wherein said strip (62a) has been flattened from wire (62) having a diameter of between 0.005 and 0.010 inches (0.13 and 0.25 mm).
Claim 16
Dependent Claim
30 words
A magnetic type electronic theft detection apparatus according to claim 4, wherein said strip (62a) has been flattened from wire (62) having a diameter of about 0.008 inches (0.20 mm).
Claim 17
Dependent Claim
27 words
A magnetic type electronic theft detection apparatus according to claim 16, wherein said strip (62a) has been flattened to a thickness of about 0.002 inches (0.05 mm).
Claim 18
Dependent Claim
29 words
A magnetic type electronic theft detection apparatus according to claim 5, wherein said wire (62) has been flattened by rolling same between a pair of rolls at room temperature.
Claim 19
Dependent Claim
29 words
A magnetic type electronic theft detection apparatus according to claim 5, wherein said wire (62) has been flattened to a thickness of about one fourth of its original diameter.
Claim 20
Dependent Claim
83 words
A responder target (32) for use in a magnetic theft detection system of the type in which an alternating magnetic interrogation field is generated in an interrogation zone and magnetic responses produced by a responder target passing through said interrogation zone are detected and, in response thereto, an alarm is actuated, said target (32) comprising an elongated strip (45) of an easily saturable magnetic material which has been pressed to change its cross-section and heat treated thereafter to substantially increase its magnetic permeability.
Claim 21
Dependent Claim
17 words
A responder target according to claim 20, wherein said strip (45) has been pressed by cold rolling.
Claim 22
Dependent Claim
22 words
A responder target according to claim 21 wherein said strip (45) has been rolled from a round cross-section to a flattened cross-section.
Claim 23
Dependent Claim
27 words
A responder target according to claim 20, wherein said strip (45) has been maintained free of stresses in all directions other than in the direction of pressing.
Claim 24
Dependent Claim
31 words
A responder target according to claim 23, wherein said easily saturable magnetic material from which said strip (45) has been pressed is wire (62) which has been drawn and heat treated.
Claim 25
Dependent Claim
20 words
A responder target according to claim 20 wherein said easily saturable material is a nickel-iron alloy containing about 80% nickel.
Claim 26
Dependent Claim
30 words
A responder target according to claim 25, wherein said alloy contains one or more metals taken from the group consisting of copper, titanium, niobium, vanadium, molybdenum, chromium and mixtures thereof.
Claim 27
Dependent Claim
23 words
A responder target according to claim 25, wherein said alloy contains from 2% to 8%, by total weight of the alloy, of copper.
Claim 28
Dependent Claim
21 words
A responder target according to claim 25, wherein said alloy contains about 5%, by total weight of the alloy, of copper.
Claim 29
Dependent Claim
14 words
A responder target according to claim 25, wherein said alloy contains about 4% molybdenum.
Claim 30
Dependent Claim
17 words
A responder target according to claim 23, wherein said easily saturable magnetic material is Permalloy wire (62).
Claim 31
Dependent Claim
41 words
A responder target according to claim 30, wherein said flattened strip (45) has been heat treated by annealing same at a temperature of at least 650 degrees Centigrade in an annealing atmosphere for a duration of at least one half hour.
Claim 32
Dependent Claim
40 words
A responder target according to claim 30 wherein said flattened strip (45) has been heat treated by annealing same at a temperature of at least 850 degrees Centigrade in an annealing atmosphere for a duration of at least one minute.
Claim 33
Dependent Claim
43 words
A responder target according to claim 30, wherein said flattened strip (45) has been heat treated by annealing same in an atmosphere consisting essentially of one of the group of disassociated ammonia, dry hydrogen, an inert gas, a mixture thereof and a vacuum.
Claim 34
Dependent Claim
30 words
A responder target according to claim 23, wherein said strip (45) has been flattened from wire (62) having a diameter of between 0.005 and 0.010 inches (0.13 and 0.25 mm).
Claim 35
Dependent Claim
26 words
A responder target according to claim 23, wherein said strip (45) has been flattened from wire (62) having a diameter of about 0.008 inches (0.20 mm).
Claim 36
Dependent Claim
23 words
A responder target according to claim 35, wherein said strip (45) has been flattened to a thickness of about 0.002 inches (0.05 mm).
Claim 37
Dependent Claim
25 words
A responder target according to claim 24, wherein said wire (62) has been flattened by rolling same between a pair of rolls at room temperature.
Claim 38
Dependent Claim
29 words
A responder target electronic theft detection apparatus according to claim 24, wherein said wire (62) has been flattened to a thickness of about one fourth of its original diameter.
Claim 39
Independent Claim
87 words
A method of making a responder target for use in a magnetic theft detection system of the type in which an alternating magnetic interrogation field is generated in an interrogation zone and magnetic responses produced by a responder target passing through said interrogation zone are detected and, in response thereto, an alarm is actuated, said method comprising the steps of pressing an elongated strip of an easily saturable magnetic material to change its cross-section and thereafter heat treating the pressed strip to substantially increase its magnetic permeability.
Claim 40
Dependent Claim
16 words
A method according to claim 39, wherein said pressing is done by cold rolling said strip.
Claim 41
Dependent Claim
28 words
A method according to claim 40, wherein said strip initially has a round cross-section and said rolling is carried out to change said strip to a flattened cross-section.
Claim 42
Dependent Claim
29 words
A method of making a responder target according to claim 39, wherein said strip is maintained free of stresses in all directions other than in the direction of pressing.
Claim 43
Dependent Claim
26 words
A method of making a responder target according to claim 42, wherein said easily saturable magnetic material is wire which has been drawn and heat treated.
Claim 44
Dependent Claim
24 words
A method of making a responder target according to claim 39, wherein said easily saturable material is a nickel-iron alloy containing about 80% nickel.
Claim 45
Dependent Claim
29 words
A method according to claim 44, wherein said alloy contains one or more metals taken from the group consisting of copper, titanium, niobium, vanadium, molybdenum, chromium and mixtures thereof.
Claim 46
Dependent Claim
22 words
A method according to claim 44, wherein said alloy contains from 2% to 8%, by total weight of the alloy, of copper.
Claim 47
Dependent Claim
20 words
A method according to claim 44, wherein said alloy contains about 5%, by total weight of the alloy, of copper.
Claim 48
Dependent Claim
18 words
A method of making a responder target according to claim 44, wherein said alloy contains about 4% molybdenum.
Claim 49
Dependent Claim
20 words
A method of making a responder target according to claim 42, wherein said easily saturable magnetic material is Permalloy wire.
Claim 50
Dependent Claim
43 words
A method of making a responder target according to claim 49, wherein said flattened strip is heat treated by annealing same at a temperature of at least 650 degrees Centigrade in an annealing atmosphere for a duration of at least one half hour.
Claim 51
Dependent Claim
36 words
A method according to claim 49 wherein said flattened strip is heat treated by annealing same at a temperature of at least 850 degrees Centigrade in annealing atmosphere for a duration of at least one minute.
Claim 52
Dependent Claim
41 words
A method according to claim 49 wherein said flattened strip has been heat treated by annealing same in an atmosphere consisting essentially of one of the group of dissociated ammonia, dry hydrogen, an inert gas, a mixture thereof and a vacuum.
Claim 53
Dependent Claim
32 words
A method of making a responder target according to claim 42, wherein said strip has been flattened from wire having a diameter of between 0.005 and 0.010 inches (1.13 and 0.25 mm).
Claim 54
Dependent Claim
28 words
A method of making a responder target according to claim 42, wherein said strip has been flattened from wire having a diameter of about 0.008 inches (0.020 mm).
Claim 55
Dependent Claim
26 words
A method of making a responder target according to claim 54, wherein said strip has been flattened to a thickness of about 0.002 inches (0.05 mm).
Claim 56
Dependent Claim
28 words
A method of making a responder target according to claim 43, wherein said wire has been flattened by rolling same between a pair of rolls at room temperature.
Claim 57
Dependent Claim
28 words
A method of making a responder target according to claim 43, wherein said wire has been flattened to a thickness of about one fourth of its original diameter.
References Cited (Backward Citations)
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