Patent US2956739A successfully refreshed from Google Patents.
US2956739A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Variable pitch impellers and closure seals therefor
Assignee: Individual
•
Filing: 1957-02-13
•
Granted: 1960-10-18
•
Expires: 1977-02-13
Abstract
No abstract record available.
Inventors
- 👤 Tothill Gordon Roy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 12:48
CPC Classifications
F; F04; F04D; F04D29/00; F04D29/26; F04D29/32; F04D29/34; F04D29/36; F04D29/362; F04D29/366; F04D29/364
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
USRE18957E
Cited
US913364A
Cited
US1610010A
Cited
US1689735A
Cited
US1656019A
Cited
US1765091A
Cited
US2133485A
Cited
US2133486A
Cited
US2200952A
Cited
US2225209A
Cited
CH299479A
Cited
US2383001A
Cited
US2383002A
Cited
US2383004A
Cited
FR1040606A
Cited
GB703458A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-10-18 | 1964-04-18 | 1964-10-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-10-18 | 1968-04-18 | 1968-10-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-10-18 | 1972-04-18 | 1972-10-18 | $7700.00 | Window Closed / Lapsed |