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US3553669A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gain increasing alarm system
Assignee: Individual
•
Filing: 1967-11-16
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Granted: 1971-01-05
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Expires: 1987-11-16
Abstract
Abstract AN AUDIO SENSITIVE ALARM IS DISCLOSED BY WHICH AN ALARM IS ACTIVATED IF THE AUDIO LEVEL IN A ROOM BEING MONITORED EITHER FALLS BELOW A SELECTED LEVEL OR RISES ABOVE ANOTHER SELECTED LEVEL, AND SUBSEQUENTLY CONTINUES FOR MORE THAN TWO SECONDS OR AGAIN RISES ABOVE THE SELECTED LEVEL MORE THAN TWO SECONDS AFTER THE FIRST RISE AND LESS THAN THIRTY SECONDS AFTER THE FIRST RISE. CONTROLLED RECTIFIER AND TRIODE TRANSISTOR CIRCUITS ARE PROVIDED TO DETECT THE SELECTED RISE OR FALL OF AUDIO LEVEL AND TO CONTROL SEVERAL RELAYS. TIME DELAYS ARE PROVIDED BY CAPACITOR DISCHARGE CIRCUITS.
Inventors
- 👤 James K Merchant
- 👤 Robert Obenour
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 08:32
CPC Classifications
G; G08; G08B; G08B13/00; G08B13/16; G08B13/1654; G08B13/1672
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-01-04 | 1974-07-06 | 1975-01-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-04 | 1978-07-06 | 1979-01-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-04 | 1982-07-06 | 1983-01-05 | $7700.00 | Window Closed / Lapsed |