Patent US4675655A successfully refreshed from Google Patents.
US4675655A
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Apparatus and method for marker verification
Assignee: Sensormatic Electronics Corp
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Filing: 1985-02-11
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Granted: 1987-06-23
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Expires: 2005-02-11
Abstract
Abstract A unit and method are provided for the short range scanning of magnetic markers. The scanning unit includes an antenna adapted to provide a narrow interrogation field of short overall range. Control circuitry is provided for establishing the applied magnetic interrogation field and detecting and processing the response signal of the marker. A light emitting diode then provides a signal to the operator indicating whether a response signal is received from the marker being interrogated. The scanning unit is also equipped with a ferromagnetic plate of high magnetic coercivity for producing a dc bias field and activating the marker.
Inventors
- 👤 Philip M. Anderson
- 👤 Richard C. Ujazdowski
- 👤 Jeffrey C. Urbanski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 20:56
CPC Classifications
G; G06; G06K; G06K7/00; G06K7/08; G06K7/082; G06K7/083; G06K7/086; G06K19/00; G06K19/06; G06K19/067
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
104 words
A short range scanning unit capable of (1) energizing a correctly oriented, closely coupled magnetomechanical marker that provides an identifiable signal in response to an applied magnetic interrogation field, and (2) detecting the response signal, comprising: antenna means including a drive and receive coil providing a narrow interrogation zone and short interrogation range; control means adapted to be manually triggered upon alignment of said scanning unit directly adjacent the marker to establish the applied magnetic interrogation field and to detect and process the response signal from the marker; and indicator means for indicating if a response signal is received from the marker being interrogated.
Claim 2
Dependent Claim
104 words
A short range scanning unit capable of (1) energizing a correctly oriented, closely coupled magnetomechanical marker that provides an identifiable signal in response to an applied magnetic interrogation field, and (2) detecting the response signal, comprising: antenna means including a drive and receive coil providing a narrow interrogation zone and short interrogation range; control means adapted to be manually triggered upon alignment of said scanning unit directly adjacent the marker to establish the applied magnetic interrogation field and to detect and process the response signal from the marker; and indicator means for indicating if a response signal is received from the marker being interrogated.
Claim 3
Dependent Claim
33 words
The scanning unit recited in claim 1, including a biasing means providing a dc magnetic bias field to activate the marker to produce an identifiable signal in response to an applied interrogation field.
Claim 4
Dependent Claim
23 words
The scanning unit recited in claim 2, wherein said biasing means is a ferromagnetic plate of high magnetic coercivity adjacent said antenna means.
Claim 5
Dependent Claim
48 words
The scanning unit recited in claim 1, wherein said antenna means includes a winding template of nonmetallic magnetic material of high magnetic coercivity providing a dc magnetic bias field for activating the marker to produce an identifiable signal, said drive and receive coil being wound around said template.
Claim 6
Dependent Claim
31 words
The scanning unit recited in claim 1, wherein said control means includes means for detecting a change in the induced voltage occurring at the mechanical resonance response frequency of the marker.
Claim 7
Dependent Claim
21 words
The scanning unit recited in claim 1, wherein said control means includes means for entering an interrogation code into the unit.
Claim 8
Dependent Claim
30 words
The scanning unit recited in claim 1, wherein said control means includes comparator means for comparing the actual target response signal of the marker being interrogated to a standard signal.
Claim 9
Dependent Claim
35 words
The scanning unit recited in claim 1, wherein said control means includes timing means for controlling the duration of establishing the interrogation field, the duration of detecting the response signal, and the time interval therebetween.
Claim 10
Dependent Claim
20 words
The scanning unit recited in claim 1, wherein said scanning unit is portable thereby allowing on-site marker interrogation and detection.
Claim 11
Independent Claim
122 words
A method utilizing a scanning unit for (1) energizing a correctly oriented, closely coupled magnetomechanical marker that provides an identifiable signal in response to an applied magnetic interrogation field, and (2) detecting the response signal of the marker at short range, and comprising the steps of; establishing a short range and narrow magnetic interrogation field for application to the closely coupled marker; aligning the scanning unit directly adjacent the marker prior to triggering the unit to interrogate the marker; detecting a change in the induced voltage occurring at the mechanical resonance response frequency of the marker; comparing the actual response signal of the interrogated marker to a standard signal; indicating if the standard response signal is received from the marker being interrogated.
Claim 12
Independent Claim
122 words
A method utilizing a scanning unit for (1) energizing a correctly oriented, closely coupled magnetomechanical marker that provides an identifiable signal in response to an applied magnetic interrogation field, and (2) detecting the response signal of the marker at short range, and comprising the steps of; establishing a short range and narrow magnetic interrogation field for application to the closely coupled marker; aligning the scanning unit directly adjacent the marker prior to triggering the unit to interrogate the marker; detecting a change in the induced voltage occurring at the mechanical resonance response frequency of the marker; comparing the actual response signal of the interrogated marker to a standard signal; indicating if the standard response signal is received from the marker being interrogated.
Claim 13
Dependent Claim
46 words
The method recited in claim 10 wherein said marker comprises multiple ribbons having resonance frequencies and said method includes the additional step of repositioning the scanning unit over the marker so as to allow the reading of the resonance frequencies of said multiple ribbons in sequence.
Claim 14
Dependent Claim
35 words
The method recited in claim 10, or 11 including the additional step of activating the marker to produce an identifiable signal by exposing the marker to a dc bias field generated in the scanning unit.
Claim 15
Dependent Claim
30 words
The method recited in claim 10, or 11 including the additional step of entering an interrogation code into the scanning unit prior to triggering the unit to interrogate the marker.
Claim 16
Dependent Claim
33 words
The method recited in claim 10, or 11 including the additional step of controlling the duration of establishing the interrogation field, the duration of detecting the response signal, and the time interval therebetween.
Claim 17
Dependent Claim
18 words
The method recited in claim 10, including the additional step of simultaneously reading resonance frequencies of ribbon markers.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-06-22 | 1990-12-22 | 1991-06-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-06-22 | 1994-12-22 | 1995-06-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-06-22 | 1998-12-22 | 1999-06-23 | $7700.00 | Window Closed / Lapsed |