Patent US2322526A successfully refreshed from Google Patents.
US2850033A
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US
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Automatic air vent valve
Assignee: NL Industries Inc
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Filing: 1953-05-05
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Granted: 1958-09-02
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Expires: 1973-05-05
Abstract
No abstract record available.
Inventors
- 👤 Norman F Hartle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:17
CPC Classifications
F; F24; F24D; F24D19/00; F24D19/08; F24D19/082; F24D19/083; F24D19/085; F24D19/087; F16; F16K; F16K31/00; F16K31/001; Y; Y10; Y10T; Y10T137/00; Y10T137/2931; Y10T137/3003; Y10T137/3084
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1365768A
Cited
US2331431A
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US2493604A
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US2601216A
Cited
US2713871A
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US2727001A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-09-01 | 1962-03-03 | 1962-09-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-09-01 | 1966-03-03 | 1966-09-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-09-01 | 1970-03-03 | 1970-09-02 | $7700.00 | Window Closed / Lapsed |