Patent US3306983A successfully refreshed from Google Patents.
US3306983A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Call transfer system
Assignee: AT&T Inc
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Filing: 1963-12-20
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Granted: 1967-02-28
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Expires: 1983-12-20
Abstract
No abstract record available.
Inventors
- 👤 James M Goodwin
- 👤 Richard L Hayes
- 👤 John W Loofbourrow
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 15:53
CPC Classifications
H; H04; H04M; H04M3/00; H04M3/42; H04M3/58; H04Q; H04Q3/00; H04Q3/0004
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
117 words
IN A TELEPHONE SWITCHING SYSTEM IN COMBINATION A FIRST SWITCHING CENTER, A SECOND SWITCHING CENTER CONNECTED TO SAID FIRST SWITCHING CENTER, A FIRST AND A SECOND SUBSCRIBER STATION CONNECTED TO SAID SECOND SWITCHING CENTER, AN INCOMING TRUNK CONNECTED TO SAID FIRST SWITCHING CENTER, MEANS RESPONSIVE TO CALLING SIGNALS TO ESTABLISH A COMMUNICATION PATH FROM SAID INCOMING TRUNK TO SAID FIRST SUBSCRIBER STATION THROUGH BOTH OF SAID SWITCHING CENTERS, MEANS CONTROLLED FROM SAID FIRST SUBSCRIBER STATION FOR TRANSMITTING VOICE FREQUENCY SIGNALS BACK THROUGH SAID SECOND SWITCHING CENTER TO SAID FIRST SWITCHING CENTER, AND MEANS AT SAID FIRST SWITCHING CENTER RESPONSIVE TO SAID VOICE FREQUENCY SIGNALS TO ESTABLISH A PATH FROM SAID INCOMING TRUNK TO SAID SECOND SUBSCRIBER STATION.
Claim 2
Dependent Claim
117 words
IN A TELEPHONE SWITCHING SYSTEM IN COMBINATION A FIRST SWITCHING CENTER, A SECOND SWITCHING CENTER CONNECTED TO SAID FIRST SWITCHING CENTER, A FIRST AND A SECOND SUBSCRIBER STATION CONNECTED TO SAID SECOND SWITCHING CENTER, AN INCOMING TRUNK CONNECTED TO SAID FIRST SWITCHING CENTER, MEANS RESPONSIVE TO CALLING SIGNALS TO ESTABLISH A COMMUNICATION PATH FROM SAID INCOMING TRUNK TO SAID FIRST SUBSCRIBER STATION THROUGH BOTH OF SAID SWITCHING CENTERS, MEANS CONTROLLED FROM SAID FIRST SUBSCRIBER STATION FOR TRANSMITTING VOICE FREQUENCY SIGNALS BACK THROUGH SAID SECOND SWITCHING CENTER TO SAID FIRST SWITCHING CENTER, AND MEANS AT SAID FIRST SWITCHING CENTER RESPONSIVE TO SAID VOICE FREQUENCY SIGNALS TO ESTABLISH A PATH FROM SAID INCOMING TRUNK TO SAID SECOND SUBSCRIBER STATION.
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) | 1970-02-27 | 1970-08-29 | 1971-02-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-02-27 | 1974-08-29 | 1975-02-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-02-27 | 1978-08-29 | 1979-02-28 | $7700.00 | Window Closed / Lapsed |