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US2221346A
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Air diffusing means
Assignee: Chicago Pump Co
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Filing: 1938-07-13
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Granted: 1940-11-12
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Expires: 1958-07-13
Abstract
No abstract record available.
Inventors
- 👤 Jr Augustus C Durdin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 14:30
CPC Classifications
C; C02; C02F; C02F3/00; C02F3/02; C02F3/12; C02F3/20; B; B01; B01F; B01F23/00; B01F23/20; B01F23/23; B01F23/231; B01F23/23105; B01F23/2311; B01F23/23114; B01F23/231142; B01F23/231143; B01F23/2312; B01F23/23123; B01F23/23115; B01F23/231151; B01F23/23126; B01F23/231265; Y; Y02; Y02W; Y02W10/00; Y02W10/10
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1943-11-12 | 1944-05-13 | 1944-11-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1947-11-12 | 1948-05-13 | 1948-11-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1951-11-12 | 1952-05-13 | 1952-11-12 | $7700.00 | Window Closed / Lapsed |