Patent US2979897A successfully refreshed from Google Patents.
US2979897A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ullage compensators for pressurizing systems
Assignee: North American Aviation Corp
•
Filing: 1954-04-26
•
Granted: 1961-04-18
•
Expires: 1974-04-26
Abstract
No abstract record available.
Inventors
- 👤 Walter R Studhalter
- 👤 Lowell M Miller
- 👤 Weldon O Bergreen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 13:11
CPC Classifications
B; B64; B64G; B64G1/00; B64G1/22; B64G1/40; B64G1/402; F; F02; F02K; F02K9/00; F02K9/42; F02K9/44; F02K9/50
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US2546055A
Cited
US2663320A
Cited
US2648196A
Cited
US2638932A
Cited
US2634577A
Cited
US2611393A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-04-17 | 1964-10-17 | 1965-04-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-04-17 | 1968-10-17 | 1969-04-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-04-17 | 1972-10-17 | 1973-04-18 | $7700.00 | Window Closed / Lapsed |