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US3504801A
Expired / Lapsed
US
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Spaced wall type,reverse osmosis filter assembly
Assignee: United States Department of the Army
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Filing: 1969-07-25
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Granted: 1970-04-07
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Expires: 1989-07-25
Abstract
No abstract record available.
Inventors
- 👤 Nelson E Alexander
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 13:15
CPC Classifications
B; B01; B01D; B01D61/00; B01D61/02; B01D61/08; B01D63/00; B01D63/08; B01D63/082; B01D63/0822
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US3133132A
Cited
US3456805A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-04-06 | 1973-10-06 | 1974-04-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-04-06 | 1977-10-06 | 1978-04-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-04-06 | 1981-10-06 | 1982-04-07 | $7700.00 | Window Closed / Lapsed |