← Back to Patent Explorer
US5469142A Expired / Lapsed US ⏱️ 0.0 years remaining

Electronic article surveillance system having enhanced tag deactivation capacity

Assignee: Tyco Fire and Security GmbH
•
Filing: 1994-08-10
•
Granted: 1995-11-21
•
Expires: 2014-08-10
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract An electronic article surveillance tag deactivation system includes a transmitter, a receiver, a deactivation coil and a controller (microprocessor) for establishing time periods for operation of the transmitter, the receiver and the deactivation coil, and for selectively varying detection sensitivity of the receiver. Detection of a tag prior to deactivation is effected with the receiver at low sensitivity and redetection of the tag subsequent to deactivation is effected with the receiver at high sensitivity.

Inventors

  • 👤 Adam S. Bergman
  • 👤 Douglas A. Drew

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 19:32
CPC Classifications
G; G08; G08B; G08B13/00; G08B13/22; G08B13/24; G08B13/2402; G08B13/2405; G08B13/2414; G08B13/242

Claims Analysis

Total Claims: 24
Claim 1
Independent Claim 46 words
An electronic article surveillance tag deactivation system, comprising: (a) a transmitter; (b) a receiver; (c) a deactivation coil; and (d) control means for establishing time periods for operation of said transmitter, said receiver and said deactivation coil, and for selectively varying detection sensitivity of said receiver.
Claim 2
Dependent Claim 46 words
An electronic article surveillance tag deactivation system, comprising: (a) a transmitter; (b) a receiver; (c) a deactivation coil; and (d) control means for establishing time periods for operation of said transmitter, said receiver and said deactivation coil, and for selectively varying detection sensitivity of said receiver.
Claim 3
Dependent Claim 96 words
The system claimed in claim 1, wherein said control means sets a time period for operation of said transmitter, a successive first time period for operation of said receiver, a successive second time period upon the receiver's detection of a tag for operation of said deactivation coil, a successive third time period for operation of said transmitter and a successive fourth time period for operation of said receiver, said control means changing the receiver detection sensitivity from a first sensitivity in said successive first time period to a second sensitivity in said successive fourth time period.
Claim 4
Dependent Claim 16 words
The system claimed in claim 2, wherein said second sensitivity is higher than said first sensitivity.
Claim 5
Dependent Claim 27 words
The system claimed in claim 1, wherein said receiver comprises a variable gain amplifier and wherein said control means controls the gain of said variable gain amplifier.
Claim 6
Dependent Claim 16 words
The system claimed in claim 4, wherein said variable gain amplifier is a programmable gain amplifier.
Claim 7
Dependent Claim 32 words
A receiver for an electronic article surveillance tag deactivation system, said receiver receiving signals from tags and controllable to exhibit variable tag detection sensitivity independently of amplitudes of the received tag signals.
Claim 8
Dependent Claim 32 words
A receiver for an electronic article surveillance tag deactivation system, said receiver receiving signals from tags and controllable to exhibit variable tag detection sensitivity independently of amplitudes of the received tag signals.
Claim 9
Dependent Claim 20 words
The receiver claimed in claim 6, comprising a variable gain amplifier controllable to provide said receiver variable tag detection sensitivity.
Claim 10
Dependent Claim 16 words
The receiver claimed in claim 7, wherein said variable gain amplifier is a programmable gain amplifier.
Claim 11
Independent Claim 76 words
A method for deactivating electronic article surveillance tags, comprising the steps of: (a) establishing a tag detection field; (b) providing a receiver having at least first and second different tag detection sensitivities; (c) setting said receiver to said first tag detection sensitivity and, upon detection of a tag by said receiver, applying a tag deactivating field to said tag; (d) reestablishing said tag detection field; and (e) setting said receiver to said second tag detection sensitivity.
Claim 12
Independent Claim 76 words
A method for deactivating electronic article surveillance tags, comprising the steps of: (a) establishing a tag detection field; (b) providing a receiver having at least first and second different tag detection sensitivities; (c) setting said receiver to said first tag detection sensitivity and, upon detection of a tag by said receiver, applying a tag deactivating field to said tag; (d) reestablishing said tag detection field; and (e) setting said receiver to said second tag detection sensitivity.
Claim 13
Dependent Claim 30 words
The method claimed in claim 9, including the further step of providing an alert indication upon the receiver's detection of said tag when set at said second tag detection sensitivity.
Claim 14
Dependent Claim 40 words
The method claimed in claim 10, including the further step of establishing a time period for practice of said step of providing an alert indication upon said receiver detection of said tag when set at said second tag detection sensitivity.
Claim 15
Dependent Claim 22 words
The method claimed in claim 9 wherein said second tag detection sensitivity is selected to be higher than said first detection sensitivity.
Claim 16
Dependent Claim 19 words
The method claimed in claim 9 wherein said steps (a) and (d) are practiced by using the same transmitter.
Claim 17
Independent Claim 86 words
A method for deactivating electronic article surveillance tags, comprising the steps of: (a) establishing a tag detection field; (b) providing a receiver having at least first and second different tag detection sensitivities; (c) setting said receiver to said second tag detection sensitivity and, upon detection of a tag by said receiver, setting said receiver to said first tag detection sensitivity; and (d) upon redetection of said tag by said receiver when set to said first tag detection sensitivity, applying a tag deactivating field to said tag.
Claim 18
Independent Claim 86 words
A method for deactivating electronic article surveillance tags, comprising the steps of: (a) establishing a tag detection field; (b) providing a receiver having at least first and second different tag detection sensitivities; (c) setting said receiver to said second tag detection sensitivity and, upon detection of a tag by said receiver, setting said receiver to said first tag detection sensitivity; and (d) upon redetection of said tag by said receiver when set to said first tag detection sensitivity, applying a tag deactivating field to said tag.
Claim 19
Dependent Claim 44 words
The method claimed in claim 14, including the further steps of establishing a time period upon setting said receiver to said first detection sensitivity for said tag redetection and providing an alert indication upon the receiver's not redetecting said tag during said time period.
Claim 20
Dependent Claim 32 words
The method claimed in claim 14, including the further steps, practiced after completion of said step (d), of resetting said receiver to said second detection sensitivity and reestablishing said tag detection field.
Claim 21
Dependent Claim 30 words
The method claimed in claim 16, including the further step of providing an alert indication upon the receiver's detection of said tag when reset to said second tag detection sensitivity.
Claim 22
Dependent Claim 40 words
The method claimed in claim 17, including the further step of establishing a time period for practice of said step of providing an alert indication upon said receiver detection of said tag when set at said second tag detection sensitivity.
Claim 23
Dependent Claim 24 words
The method claimed in claim 16 wherein said steps of establishing and reestablishing said tag detection fields are practiced by using the same transmitter.
Claim 24
Dependent Claim 22 words
The method claimed in claim 14, wherein said second tag detection sensitivity is selected to be higher than said first detection sensitivity.

References Cited (Backward Citations)

US3938044A Cited
US4476459A Cited
US4881061A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1998-11-20 1999-05-22 1999-11-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-11-20 2003-05-22 2003-11-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2006-11-20 2007-05-22 2007-11-21 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag