Patent US4723638A successfully refreshed from Google Patents.
Patent US3385356A successfully refreshed from Google Patents.
US3385356A
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Heat exchanger with improved extended surface
Assignee: Individual
•
Filing: 1967-05-18
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Granted: 1968-05-28
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Expires: 1987-05-18
Abstract
No abstract record available.
Inventors
- 👤 Dalin David
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:46
CPC Classifications
F; F24; F24H; F24H1/00; F24H1/22; F24H1/24; F24H1/26; F24H1/28; F24H1/282; B; B23; B23K; B23K20/00; B23K20/22; B23K20/227; F24H3/00; F24H3/02; F24H3/06; F24H3/10; F24H3/105; F24H9/00; F24H9/0005; F24H9/001; F24H9/0026; F28; F28F; F28F1/00; F28F1/10; F28F1/12; F28F1/124; F28F1/24; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/4935; Y10T29/49377; Y10T29/49378
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1971-05-28 | 1971-11-27 | 1972-05-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-05-28 | 1975-11-27 | 1976-05-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-05-28 | 1979-11-27 | 1980-05-28 | $7700.00 | Window Closed / Lapsed |