US3484559A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Interstage signalling system using discrete currents or voltages
Assignee: Post Office
•
Filing: 1966-07-28
•
Granted: 1969-12-16
•
Expires: 1986-07-28
Abstract
No abstract record available.
Inventors
- 👤 Donald Frank Rigby
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 06:18
CPC Classifications
H; H04; H04Q; H04Q3/00; H04Q3/42
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US2087405A
Cited
US2493256A
Cited
US2559601A
Cited
US2693504A
Cited
US2620400A
Cited
US2590262A
Cited
US2807671A
Cited
US2999227A
Cited
US3009021A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-12-15 | 1973-06-16 | 1973-12-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-12-15 | 1977-06-16 | 1977-12-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-12-15 | 1981-06-16 | 1981-12-16 | $7700.00 | Window Closed / Lapsed |