Patent US3312787A successfully refreshed from Google Patents.
US3312787A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Signaling system
Assignee: Stromberg Carlson Corp
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Filing: 1963-10-17
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Granted: 1967-04-04
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Expires: 1983-10-17
Abstract
No abstract record available.
Inventors
- 👤 Adam A Jorgensen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 22:56
CPC Classifications
H; H04; H04M; H04M19/00; H04M19/02; H04M19/026
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
94 words
IN A SIGNALING SYSTEM, A TWO CONDUCTOR SIGNALING CHANNEL, A D.C. POTENTIAL SOURCE CONNECTED ACROSS ONE END OF SAID TWO CONDUCTOR CHANNEL, A SOURCE OF A.C. SIGNALS, CONTROL MEANS FOR SELECTIVELY APPLYING SAID A.C. SIGNALS TO SAID TWO CONDUCTOR CHANNEL IN SERIES WITH SAID D.C. POTENTIAL SOURCE AT SAID ONE END THEREOF, RINGER MEANS CONNECTED ACROSS SAID TWO CONDUCTOR CHANNEL RESPONSIVE TO AND CAPABLE OF PASSING ONLY SAID A.C. SIGNALS, A DIRECT CURRENT RESPONSIVE DEVICE, SWITCH MEANS ACTUATABLE TO SELECTIVELY DISCONNECT SAID RINGER MEANS AND CONNECT SAID DIRECT CURRENT RESPONSIVE DEVICE ACROSS SAID TWO
Claim 2
Dependent Claim
94 words
IN A SIGNALING SYSTEM, A TWO CONDUCTOR SIGNALING CHANNEL, A D.C. POTENTIAL SOURCE CONNECTED ACROSS ONE END OF SAID TWO CONDUCTOR CHANNEL, A SOURCE OF A.C. SIGNALS, CONTROL MEANS FOR SELECTIVELY APPLYING SAID A.C. SIGNALS TO SAID TWO CONDUCTOR CHANNEL IN SERIES WITH SAID D.C. POTENTIAL SOURCE AT SAID ONE END THEREOF, RINGER MEANS CONNECTED ACROSS SAID TWO CONDUCTOR CHANNEL RESPONSIVE TO AND CAPABLE OF PASSING ONLY SAID A.C. SIGNALS, A DIRECT CURRENT RESPONSIVE DEVICE, SWITCH MEANS ACTUATABLE TO SELECTIVELY DISCONNECT SAID RINGER MEANS AND CONNECT SAID DIRECT CURRENT RESPONSIVE DEVICE ACROSS SAID TWO
References Cited (Backward Citations)
US3192323A
Cited
US3059058A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1970-04-03 | 1970-10-03 | 1971-04-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-04-03 | 1974-10-03 | 1975-04-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-04-03 | 1978-10-03 | 1979-04-04 | $7700.00 | Window Closed / Lapsed |