Patent US3284575A successfully refreshed from Google Patents.
US3284575A
Expired / Lapsed
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Threshold responsive isolation for party telephone lines
Assignee: Stromberg Carlson Corp
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Filing: 1963-12-09
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Granted: 1966-11-08
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Expires: 1983-12-09
Abstract
No abstract record available.
Inventors
- 👤 Kal W Howard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 09:01
CPC Classifications
H; H04; H04M; H04M1/00; H04M1/68; H04M1/70; H04Q; H04Q5/00; H04Q5/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
90 words
A PARTY TELEPHONE LINE COMPRISING IN COMBINATION, A PAIR OF TELEPHONE WIRES, A DIRECT CURRENT VOLTAGE SOURCE, A PLURALITY OF STATION SETS EACH HAVING A HOOK SWITCH FOR CONNECTING THE SET BETWEEN SAID WIRES, AND A VOLTAGE THRESHOLD DEVICE CONNECTED BETWEEN EACH OF THE SETS AND THE SAME ONE OF THE WIRES WHICH BREAKS DOWN TO PASS CURRENT WHEN ENCOUNTERING SUBSTANTIALLY THE ENTIRE VOLTAGE FROM THE SOURCE BUT REMAINS NON-CONDUCTIVE WHEN ENCOUNTERING ONLY THE POTENTIAL DROP ACROSS THE LINE DUE TO CURRENT FLOW THROUGH THE STATION SET FROM SAID SOURCE.
Claim 2
Dependent Claim
90 words
A PARTY TELEPHONE LINE COMPRISING IN COMBINATION, A PAIR OF TELEPHONE WIRES, A DIRECT CURRENT VOLTAGE SOURCE, A PLURALITY OF STATION SETS EACH HAVING A HOOK SWITCH FOR CONNECTING THE SET BETWEEN SAID WIRES, AND A VOLTAGE THRESHOLD DEVICE CONNECTED BETWEEN EACH OF THE SETS AND THE SAME ONE OF THE WIRES WHICH BREAKS DOWN TO PASS CURRENT WHEN ENCOUNTERING SUBSTANTIALLY THE ENTIRE VOLTAGE FROM THE SOURCE BUT REMAINS NON-CONDUCTIVE WHEN ENCOUNTERING ONLY THE POTENTIAL DROP ACROSS THE LINE DUE TO CURRENT FLOW THROUGH THE STATION SET FROM SAID SOURCE.
References Cited (Backward Citations)
US1899014A
Cited
US2841647A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-11-07 | 1970-05-09 | 1970-11-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-11-07 | 1974-05-09 | 1974-11-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-11-07 | 1978-05-09 | 1978-11-08 | $7700.00 | Window Closed / Lapsed |