Patent US3137770A successfully refreshed from Google Patents.
US3137770A
Expired / Lapsed
US
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Telephone call holding arrangement
Assignee: AT&T Inc
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Filing: 1961-11-17
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Granted: 1964-06-16
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Expires: 1981-11-17
Abstract
No abstract record available.
Inventors
- 👤 Michael E Doyle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 21:15
CPC Classifications
H; H04; H04Q; H04Q3/00
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
83 words
IN A TELEPHONE SYSTEM HAVING AUTOMATIC SWITCHING EQUIPMENT OPERATED TO ESTABLISH AN INTERCONNECTION BETWEEN A CALLING LINE AND A CALLED LINE AND RELEASABLE TO DISESTABLISH A SAID INTERCONNECTION; HOLDING MEANS OPERATED INCIDENT TO THE ESTABLISHMENT OF A SAID INTERCONNECTION TO HOLD SAID EQUIPMENT OPERATED, SAID HOLDING MEANS BEING RELEASABLE TO RELEASE SAID EQUIPMENT; A TELEPHONE DIAL FOR TRANSMITTING DIFFERENT SIGNALS ON SAID CALLED LINE; AND CIRCUIT MEANS RESPONSIVE TO A PARTICULAR SIGNAL FROM SAID DIAL FOR AUTOMATICALLY DISCONNECTING SAID CALLED LINE FROM SAID
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) | 1967-06-16 | 1967-12-16 | 1968-06-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-06-16 | 1971-12-16 | 1972-06-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-06-16 | 1975-12-16 | 1976-06-16 | $7700.00 | Window Closed / Lapsed |