US2731709A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making internally finned heat exchanger tubes
Assignee: Brown Fintube Co
•
Filing: 1950-09-18
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Granted: 1956-01-24
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Expires: 1970-09-18
Abstract
No abstract record available.
Inventors
- 👤 Hugh L Gaddis
- 👤 Glenn W Myers
- 👤 Oral S Welsh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:36
CPC Classifications
F; F28; F28F; F28F13/00; F28F13/06; B; B21; B21C; B21C37/00; B21C37/06; B21C37/15; B21C37/22; B21C37/225; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/4935; Y10T29/49377; Y10T29/49378; Y10T29/49384
Claims Analysis
Total Claims: 0
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-01-23 | 1959-07-25 | 1960-01-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-01-23 | 1963-07-25 | 1964-01-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-01-23 | 1967-07-25 | 1968-01-24 | $7700.00 | Window Closed / Lapsed |