US2594719A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Voice-frequency telephone signaling system
Assignee: Automatic Electric Laboratories Inc
•
Filing: 1946-04-25
•
Granted: 1952-04-29
•
Expires: 1966-04-25
Abstract
No abstract record available.
Inventors
- 👤 Beale Charles Edmund
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 20:45
CPC Classifications
H; H04; H04Q; H04Q3/00; H04Q3/0016
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2188461A
Cited
US2154776A
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GB489609A
Cited
US2302071A
Cited
US2424577A
Cited
US2407150A
Cited
US2383541A
Cited
US2374884A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-04-29 | 1955-10-29 | 1956-04-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-04-29 | 1959-10-29 | 1960-04-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-04-29 | 1963-10-29 | 1964-04-29 | $7700.00 | Window Closed / Lapsed |