US2562699A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Filter and method of backwashing same
Assignee: Permutit Co
•
Filing: 1949-06-17
•
Granted: 1951-07-31
•
Expires: 1969-06-17
Abstract
No abstract record available.
Inventors
- 👤 Cooperson Norman
- 👤 Albert W Kingsbury
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 20:45
CPC Classifications
B; B01; B01D; B01D37/00; B01D37/02; B01D29/00; B01D29/11; B01D29/31; B01D29/33; B01D29/50; B01D29/52; B01D29/62; B01D29/66; B01D29/661; B01D29/88; B01D29/90; B01D29/96; B01D2201/00; B01D2201/04; B01D2201/043; B01D2201/0446; B01D2201/28; B01D2201/287
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1040090A
Cited
US1246850A
Cited
US1263226A
Cited
US1359162A
Cited
US2347927A
Cited
US2423172A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-07-30 | 1955-01-29 | 1955-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-07-30 | 1959-01-29 | 1959-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-07-30 | 1963-01-29 | 1963-07-31 | $7700.00 | Window Closed / Lapsed |