US3133995A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Call awaiting signal telephone circuits
Assignee: AT&T Inc
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Filing: 1961-09-18
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Granted: 1964-05-19
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Expires: 1981-09-18
Abstract
No abstract record available.
Inventors
- 👤 Zarouni Alfred
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:53
CPC Classifications
H; H04; H04Q; H04Q3/00; H04Q3/0004
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
103 words
IN COMBINATION, IN A TELEPHONE SWITCHING SYSTEM A TELEPHONE SUBSCRIBER''S LINE, TWO SETS OF SELECTABLE LINE TERMINAL APPEARANCES THEREFOR, MEANS FOR SELECTING EITHER OF SAID LINE TERMINAL APPEARANCES WHEN THEY ARE NOT BUSY, MEANS RESPONSIVE TO THE SELECTION OF EITHER OF SAID LINE TERMINAL APPEARANCES WHEN THE OTHER OF SAID LINE TERMINAL APPEARANCES AND SAID LINE ARE BUSY FOR TRANSMITTING A CALL-AWAITING TONE TO THE SUBSCRIBER''S LINE, AND MEANS RESPONSIVE TO THE TERMINATION OF THE BUSY CALL FOR INTERCONNECTING THE SUBSCRIBER''S LINE WITH THE SAID OTHER TERMINAL APPEARANCE, AND MEANS FOR THEREAFTER APPLYING RINGING CURRENT TO THE SUBSCRIBER''S LINE FOR CALLING THE SUBSCRIBER.
Claim 2
Dependent Claim
103 words
IN COMBINATION, IN A TELEPHONE SWITCHING SYSTEM A TELEPHONE SUBSCRIBER''S LINE, TWO SETS OF SELECTABLE LINE TERMINAL APPEARANCES THEREFOR, MEANS FOR SELECTING EITHER OF SAID LINE TERMINAL APPEARANCES WHEN THEY ARE NOT BUSY, MEANS RESPONSIVE TO THE SELECTION OF EITHER OF SAID LINE TERMINAL APPEARANCES WHEN THE OTHER OF SAID LINE TERMINAL APPEARANCES AND SAID LINE ARE BUSY FOR TRANSMITTING A CALL-AWAITING TONE TO THE SUBSCRIBER''S LINE, AND MEANS RESPONSIVE TO THE TERMINATION OF THE BUSY CALL FOR INTERCONNECTING THE SUBSCRIBER''S LINE WITH THE SAID OTHER TERMINAL APPEARANCE, AND MEANS FOR THEREAFTER APPLYING RINGING CURRENT TO THE SUBSCRIBER''S LINE FOR CALLING THE SUBSCRIBER.
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) | 1967-05-19 | 1967-11-18 | 1968-05-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-05-19 | 1971-11-18 | 1972-05-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-05-19 | 1975-11-18 | 1976-05-19 | $7700.00 | Window Closed / Lapsed |