Patent US991841A successfully refreshed from Google Patents.
Patent US716653A successfully refreshed from Google Patents.
Patent US2809528A successfully refreshed from Google Patents.
US2809528A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for determining the vertical in an aircraft
Assignee: Individual
•
Filing: 1952-02-06
•
Granted: 1957-10-15
•
Expires: 1972-02-06
Abstract
No abstract record available.
Inventors
- 👤 Serson Paul Horne
- 👤 Mack Stanley Zaner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 15:44
CPC Classifications
G; G01; G01C; G01C19/00; G01C19/02; G01C19/44; Y; Y10; Y10T; Y10T74/00; Y10T74/12; Y10T74/1218
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US2382993A
Cited
US2440189A
Cited
US2598672A
Cited
US2497614A
Cited
US2608867A
Cited
US2553217A
Cited
US2597151A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-10-14 | 1961-04-15 | 1961-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-10-14 | 1965-04-15 | 1965-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-10-14 | 1969-04-15 | 1969-10-15 | $7700.00 | Window Closed / Lapsed |