Patent US3439476A successfully refreshed from Google Patents.
US3439476A
Expired / Lapsed
US
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Gas purification apparatus
Assignee: CAV Ltd
•
Filing: 1967-11-24
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Granted: 1969-04-22
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Expires: 1987-11-24
Abstract
No abstract record available.
Inventors
- 👤 Basil Edward Knight
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:06
CPC Classifications
F; F01; F01N; F01N3/00; F01N3/08; F01N3/0892; B; B03; B03C; B03C3/00; B03C3/02; B03C3/04; B03C3/14; B03C3/15; B03C3/34; B03C3/66; B03C3/70; F01N3/10; F01N3/24; F01N3/38; Y; Y10; Y10S; Y10S55/00; Y10S55/30
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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DE533036C
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US1334231A
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GB120994A
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US1332981A
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FR701007A
Cited
US2726730A
Cited
US2659449A
Cited
GB758063A
Cited
US3116433A
Cited
US3033918A
Cited
US3238702A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-04-21 | 1972-10-21 | 1973-04-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-04-21 | 1976-10-21 | 1977-04-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-04-21 | 1980-10-21 | 1981-04-22 | $7700.00 | Window Closed / Lapsed |