US5130698A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Deactivatable anti-theft security strip
Assignee: Vacuumschmelze GmbH and Co KG
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Filing: 1991-02-25
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Granted: 1992-07-14
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Expires: 2011-02-25
Abstract
Abstract A deactivatable anti-theft security strip has a soft-magnetic constituent and a hard-magnetic constituent. The hard-magnetic constituent is used for two purposes. It is used first to stress the soft-magnetic constituent and thereby to promote a fast magnetic reversal, and it is also used to deactivate the strip by magnetization. The pre-stressed, soft-magnetic constituent produces defined, steep pulses even in the presence of a slow magnetic reversal, so that the anti-theft security strip is especially suited for alternating fields having low frequencies, for example 50 or 60 Hz.
Inventors
- 👤 Gerd Rauscher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 12:31
CPC Classifications
G; G08; G08B; G08B13/00; G08B13/22; G08B13/24; G08B13/2402; G08B13/2405; G08B13/2408; G08B13/2411; G08B13/2428; G08B13/2437; G08B13/2442
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
131 words
A deactivatable anti-theft security strip which is magnetically reversible in an alternating field of an examination zone thereby to generate pulses having characteristic harmonics in a reception coil, said security strip comprising: a soft-magnetic constituent and a hard-magnetic constituent formed into a composite elongated member with the soft-magnetic and hard-magnetic constituents mechanically supporting each other; said hard-magnetic constituent being demagnetized in an activated condition of said security strip; said soft-magnetic constituent having a coercivity field strength which is below the field strength of the alternating field in the examination zone; and said hard-magnetic constituent having a coercivity field strength which is higher than the field strength of the alternating field in the examination zone, whereby a defined Barkhausen effect is achieved in the magnetic reversal at said deactivatable anti-theft security strip.
Claim 2
Dependent Claim
131 words
A deactivatable anti-theft security strip which is magnetically reversible in an alternating field of an examination zone thereby to generate pulses having characteristic harmonics in a reception coil, said security strip comprising: a soft-magnetic constituent and a hard-magnetic constituent formed into a composite elongated member with the soft-magnetic and hard-magnetic constituents mechanically supporting each other; said hard-magnetic constituent being demagnetized in an activated condition of said security strip; said soft-magnetic constituent having a coercivity field strength which is below the field strength of the alternating field in the examination zone; and said hard-magnetic constituent having a coercivity field strength which is higher than the field strength of the alternating field in the examination zone, whereby a defined Barkhausen effect is achieved in the magnetic reversal at said deactivatable anti-theft security strip.
Claim 3
Dependent Claim
22 words
A deactivatable anti-theft security strip as claimed in claim 1 wherein said hard-magnetic constituent is magnetized for deactivating the anti-theft security strip.
Claim 4
Dependent Claim
33 words
A deactivatable anti-theft security strip is claimed in claim 2 wherein said magnetization of said hard-magnetic constituent for deactivation of said security strip is undertaken by a plurality of sections with different polarities.
Claim 5
Dependent Claim
41 words
A deactivatable anti-theft security strip as claimed in claim 1 wherein said elongated composite member has a length in millimeters which is at least approximately 4000 times as large as the cross section of the soft magnetic constituent in square millimeters.
Claim 6
Dependent Claim
36 words
A deactivatable anti-theft security strip as claimed in claim 1 wherein said hard-magnetic constituent is disposed at an exterior of said elongated member, and said soft-magnetic constituent is disposed in the interior of said elongated member.
Claim 7
Dependent Claim
33 words
A deactivatable anti-theft security strip as claimed in claim 1 wherein said composite member is formed by a wire consisting of said soft-magnetic constituent disposed inside a tube consisting of said hard-magnetic constituent.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-07-14 | 1996-01-13 | 1996-07-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-07-14 | 2000-01-13 | 2000-07-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-07-14 | 2004-01-13 | 2004-07-14 | $7700.00 | Window Closed / Lapsed |