US3765016A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Security system including means for polling the premises to be protected
Assignee: OCI Communcations Inc
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Filing: 1971-05-24
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Granted: 1973-10-09
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Expires: 1991-05-24
Abstract
Abstract A security system in which a central station is connected to a transmission loop having a plurality of series connected subscriber stations. Transmission and receiving means are located at the central station and each of the subscriber stations has means for receiving an interrogating signal from the central station and for responding with a signal indicating the condition of the alarm system at the subscriber location.
Inventors
- 👤 P Bert
- 👤 L Jedynak
- 👤 S Gulf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:37
CPC Classifications
G; G08; G08B; G08B26/00; G08B26/005; G08B29/00; G08B29/02
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
138 words
A security system including a central station, a transmission loop connected to said central station, a plurality of subscriber stations connected in series in said loop, transmission means at the central station for periodically sending interrogating signals to each subscriber station, sensing means at each subscriber station, means for providing a signal indicative of the condition of said sensing means, means at each subscriber station responding to the central station interrogating signals for sending a signal indicative of the condition of said sensing means, means for treating a fault on said transmission loop including a normally closed relay at each subscriber''s station connected in said loop, and means at each subscriber''s station responsive to and requiring periodic interrogating signals, for holding said relay in a closed position, and receiving means at the central station for said subscribers'' signals.
Claim 2
Dependent Claim
138 words
A security system including a central station, a transmission loop connected to said central station, a plurality of subscriber stations connected in series in said loop, transmission means at the central station for periodically sending interrogating signals to each subscriber station, sensing means at each subscriber station, means for providing a signal indicative of the condition of said sensing means, means at each subscriber station responding to the central station interrogating signals for sending a signal indicative of the condition of said sensing means, means for treating a fault on said transmission loop including a normally closed relay at each subscriber''s station connected in said loop, and means at each subscriber''s station responsive to and requiring periodic interrogating signals, for holding said relay in a closed position, and receiving means at the central station for said subscribers'' signals.
Claim 3
Dependent Claim
24 words
The circuit of claim 1 further characterized in that said transmission means includes means for transmitting said interrogating signals sequentially and at predetermined intervals.
Claim 4
Dependent Claim
24 words
The circuit of claim 1 further characterized by and including means at the central station for reversing the direction of transmission on said loop.
Claim 5
Dependent Claim
28 words
The circuit of claim 1 further characterized by and including address means at each subscriber station for comparing each interrogating signal with the address for that subscriber station.
References Cited (Backward Citations)
US3214734A
Cited
US3349374A
Cited
US3350580A
Cited
US3626403A
Cited
US3676878A
Cited
US3624649A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-08 | 1977-04-09 | 1977-10-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-08 | 1981-04-09 | 1981-10-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-08 | 1985-04-09 | 1985-10-09 | $7700.00 | Window Closed / Lapsed |