Patent US2822757A successfully refreshed from Google Patents.
US2822757A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Two-zone pumping system and method
Assignee: Kobe Inc
•
Filing: 1955-03-07
•
Granted: 1958-02-11
•
Expires: 1975-03-07
Abstract
No abstract record available.
Inventors
- 👤 Clarence J Coberly
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 07:55
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/14
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US2304303A
Cited
US2499849A
Cited
US2499356A
Cited
US2499357A
Cited
US2589671A
Cited
US2780171A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-02-10 | 1961-08-12 | 1962-02-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-02-10 | 1965-08-12 | 1966-02-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-02-10 | 1969-08-12 | 1970-02-11 | $7700.00 | Window Closed / Lapsed |