Patent US3133994A successfully refreshed from Google Patents.
US3133994A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Conference circuit for telephone switching systems
Assignee: AT&T Inc
•
Filing: 1962-03-08
•
Granted: 1964-05-19
•
Expires: 1982-03-08
Abstract
No abstract record available.
Inventors
- 👤 Zarouni Alfred
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 14:14
CPC Classifications
H; H04; H04M; H04M3/00; H04M3/42; H04M3/56; H04Q; H04Q3/00; H04Q3/0004
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
98 words
IN COMBINATION IN A CROSSBAR TELEPHONE SWITCHING SYSTEM, A SUBSCRIBER''S LINE, A CONFERENCE CIRCUIT HAVING PERMANENTLY CONNECTED THEREWITH AN INPUT BRANCH AND A PLURALITY OF OUTPUT BRANCHES, MEANS FOR ESTABLISHING A CONNECTION FROM SAID SUBSCRIBER''S LINE TO SAID INPUT BRANCH OF SAID CONFERENCE CIRCUIT, MEANS CONNECTED TO SAID INPUT BRANCH RESPONSIVE TO FURTHER SIGNALS TRANSMITTED FROM SAID SUBSCRIBER''S STATION FOR INITIATING A CALL ON ANOTHER BRANCH, AND MEANS FOR TRANSMITTING SUBSEQUENT CALL SIGNALS FROM SAID SUBSCRIBER''S STATION THROUGH SAID CONFERENCE CIRCUIT TO ESTABLISH A CONNECTION THROUGH SAID CROSSBAR SWITCHING SYSTEM TO SAID OTHER BRANCH OF SAID CONFERENCE CIRCUIT.
Claim 2
Dependent Claim
98 words
IN COMBINATION IN A CROSSBAR TELEPHONE SWITCHING SYSTEM, A SUBSCRIBER''S LINE, A CONFERENCE CIRCUIT HAVING PERMANENTLY CONNECTED THEREWITH AN INPUT BRANCH AND A PLURALITY OF OUTPUT BRANCHES, MEANS FOR ESTABLISHING A CONNECTION FROM SAID SUBSCRIBER''S LINE TO SAID INPUT BRANCH OF SAID CONFERENCE CIRCUIT, MEANS CONNECTED TO SAID INPUT BRANCH RESPONSIVE TO FURTHER SIGNALS TRANSMITTED FROM SAID SUBSCRIBER''S STATION FOR INITIATING A CALL ON ANOTHER BRANCH, AND MEANS FOR TRANSMITTING SUBSEQUENT CALL SIGNALS FROM SAID SUBSCRIBER''S STATION THROUGH SAID CONFERENCE CIRCUIT TO ESTABLISH A CONNECTION THROUGH SAID CROSSBAR SWITCHING SYSTEM TO SAID OTHER BRANCH OF SAID CONFERENCE CIRCUIT.
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) | 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 |