US2809810A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat exchange apparatus
Assignee: United Aircraft Products Inc
•
Filing: 1954-10-22
•
Granted: 1957-10-15
•
Expires: 1974-10-22
Abstract
No abstract record available.
Inventors
- 👤 Jr Frank E Carroll
- 👤 Groote Raymond S De
- 👤 Robert E Hall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 04:27
CPC Classifications
F; F01; F01M; F01M5/00; F01M5/005; F01M5/007
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US447285A
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US1599370A
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US1633759A
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GB310157A
Cited
US1934496A
Cited
US1999237A
Cited
US2034235A
Cited
US2291637A
Cited
US2460754A
Cited
US2545966A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-10-14 | 1961-04-15 | 1961-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-10-14 | 1965-04-15 | 1965-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-10-14 | 1969-04-15 | 1969-10-15 | $7700.00 | Window Closed / Lapsed |