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US2775772A
Expired / Lapsed
US
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Flush economizer
Assignee: Individual
•
Filing: 1954-04-26
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Granted: 1957-01-01
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Expires: 1974-04-26
Abstract
No abstract record available.
Inventors
- 👤 Robert H Clarke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:27
CPC Classifications
E; E03; E03D; E03D1/00; E03D1/02; E03D1/14; E03D1/142; Y; Y10; Y10S; Y10S4/00; Y10S4/01
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1784944A
Cited
US2168742A
Cited
US2241220A
Cited
US2214439A
Cited
US2514062A
Cited
US2532977A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-01-01 | 1960-07-02 | 1961-01-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-01-01 | 1964-07-02 | 1965-01-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-01-01 | 1968-07-02 | 1969-01-01 | $7700.00 | Window Closed / Lapsed |