US2531802A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Filter and valve mechanism
Assignee: Individual
•
Filing: 1944-11-30
•
Granted: 1950-11-28
•
Expires: 1964-11-30
Abstract
No abstract record available.
Inventors
- 👤 Robert Q Boyer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 17:18
CPC Classifications
B; B01; B01D; B01D35/00; B01D37/00; Y; Y10; Y10T; Y10T137/00; Y10T137/8593; Y10T137/86493; Y10T137/86501; Y10T137/87153; Y10T137/87571; Y10T137/87676; Y10T137/87684
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US743652A
Cited
US887268A
Cited
US945193A
Cited
US1338782A
Cited
US1605652A
Cited
US2197995A
Cited
US2212733A
Cited
US2129055A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-11-27 | 1954-05-29 | 1954-11-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-11-27 | 1958-05-29 | 1958-11-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-11-27 | 1962-05-29 | 1962-11-28 | $7700.00 | Window Closed / Lapsed |