US1780294A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat-exchanging apparatus
Assignee: SHAWPERKINS Manufacturing Co
•
Filing: 1929-02-01
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Granted: 1930-11-04
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Expires: 1949-02-01
Abstract
No abstract record available.
Inventors
- 👤 Jr Archibald H Davis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 12:04
CPC Classifications
F; F28; F28F; F28F9/00; F28F9/02; F28F9/0236; F28F9/0241; F28F1/00; F28F1/02; Y; Y10; Y10S; Y10S165/00; Y10S165/051; Y10S165/052; Y10S165/053; Y10S165/057
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1933-11-03 | 1934-05-05 | 1934-11-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1937-11-03 | 1938-05-05 | 1938-11-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1941-11-03 | 1942-05-05 | 1942-11-04 | $7700.00 | Window Closed / Lapsed |