Patent US4796012A successfully refreshed from Google Patents.
US4796012A
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US
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Perimeter surveillance system with sectional inhibition
Assignee: LEV ADVANCED DETECTION SYSTEMS Ltd
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Filing: 1987-03-27
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Granted: 1989-01-03
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Expires: 2007-03-27
Abstract
Abstract An improved perimeter surveillance system employs multiple intrusion sensors distributed in the field and amplifiers associated therewith. Apparatus is provided for selectably inhibiting an alarm indication from a given sensor in response to electromagnetic interference detected thereat without necessarily inhibiting the operation of alarm indications from other sensors.
Inventors
- 👤 Mordechai Schechter
- 👤 Moshe Barkay
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:54
CPC Classifications
G; G08; G08B; G08B13/00; G08B13/22; G08B13/24; G08B13/2491
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
66 words
An improved perimeter surveillance system comprising: a plurality of intrusion sensors distributed in a region to be protected; respective amplifier means associated with said plurality of intrusion sensors; and means for inhibiting an alarm indication output of an amplifier means associated with an intrusion sensor in response to simultaneous detection of electromagnetic interference detected thereat, without inhibiting the operation of other amplifier means in the system.
Claim 2
Dependent Claim
66 words
An improved perimeter surveillance system comprising: a plurality of intrusion sensors distributed in a region to be protected; respective amplifier means associated with said plurality of intrusion sensors; and means for inhibiting an alarm indication output of an amplifier means associated with an intrusion sensor in response to simultaneous detection of electromagnetic interference detected thereat, without inhibiting the operation of other amplifier means in the system.
Claim 3
Dependent Claim
15 words
Apparatus according to claim 1 and wherein said intrusion sensors comprise buried wire loop sensors.
Claim 4
Dependent Claim
37 words
Apparatus according to claim 2 and wherein said amplifier means associated with each intrusion sensor is operative to activate auxiliary apparatus, such as searchlights, cameras and audio alarms in response to sensed intrusion at said intrusion sensor.
Claim 5
Dependent Claim
30 words
Apparatus according to claim 2 and wherein additional intrusion sensors are connected in series to the buried wire loop sensor so as to define additional protection in given intrusion zones.
Claim 6
Dependent Claim
27 words
Apparatus according to claim 2 and also comprising means for providing shielding between the amplifier means and the earth to prevent false alarms due to earth fields.
Claim 7
Dependent Claim
37 words
Apparatus according to claim 1 and wherein said amplifier means associated with each intrusion sensor is operative to activate auxiliary apparatus, such as searchlights, cameras and audio alarms in response to sensed intrusion at said intrusion sensor.
Claim 8
Dependent Claim
27 words
Apparatus according to claim 1 and also comprising means for providing shielding between the amplifier means and the earth to prevent false alarms due to earth fields.
References Cited (Backward Citations)
US32468A
Cited
USRE32468E
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-01-03 | 1992-07-04 | 1993-01-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-01-03 | 1996-07-04 | 1997-01-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-01-03 | 2000-07-04 | 2001-01-03 | $7700.00 | Window Closed / Lapsed |