US2490093A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Speed control of phonograph motors
Assignee: Dictaphone Corp
•
Filing: 1944-02-08
•
Granted: 1949-12-06
•
Expires: 1964-02-08
Abstract
No abstract record available.
Inventors
- 👤 Frederick W Roberts
- 👤 John H Trevitt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:28
CPC Classifications
G; G11; G11B; G11B19/00; G11B19/20; G11B19/28; Y; Y10; Y10S; Y10S388/00; Y10S388/907; Y10S388/913
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US1157823A
Cited
US1778465A
Cited
US2100715A
Cited
US2192050A
Cited
US2303786A
Cited
US2375158A
Cited
US2362650A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1952-12-05 | 1953-06-06 | 1953-12-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-12-05 | 1957-06-06 | 1957-12-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-12-05 | 1961-06-06 | 1961-12-06 | $7700.00 | Window Closed / Lapsed |