US2681153A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of discharging a filter
Assignee: Proportioneers Inc
•
Filing: 1950-01-20
•
Granted: 1954-06-15
•
Expires: 1970-01-20
Abstract
No abstract record available.
Inventors
- 👤 Henry N Armbrust
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 03:30
CPC Classifications
B; B01; B01D; B01D29/00; B01D29/50; B01D29/52; B01D29/11; B01D29/13; B01D29/15; B01D29/62; B01D29/66; B01D35/00; B01D35/14; B01D35/147; B01D2201/00; B01D2201/04; B01D2201/0469; B01D2201/0476; B01D37/00; B01D37/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1120629A
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US1771928A
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US1992101A
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US2230174A
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US2300849A
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US2401039A
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US2390494A
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US2423172A
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US2468603A
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US2496370A
Cited
US2562730A
Cited
US2570132A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-06-14 | 1957-12-14 | 1958-06-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-06-14 | 1961-12-14 | 1962-06-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-06-14 | 1965-12-14 | 1966-06-15 | $7700.00 | Window Closed / Lapsed |