US2589672A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Closed fluid-operated free-pump system with two parallel tubings within a third tubing
Assignee: DRESSER EQUIPMENT Co
•
Filing: 1949-05-16
•
Granted: 1952-03-18
•
Expires: 1969-05-16
Abstract
No abstract record available.
Inventors
- 👤 Clarence J Coberly
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 13:59
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/12
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1616773A
Cited
US1630902A
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US1765921A
Cited
US2100560A
Cited
US2230830A
Cited
US2277181A
Cited
US2338903A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-03-18 | 1955-09-17 | 1956-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-03-18 | 1959-09-17 | 1960-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-03-18 | 1963-09-17 | 1964-03-18 | $7700.00 | Window Closed / Lapsed |