US1904875A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat exchanger
Assignee: Ingersoll Rand Co
•
Filing: 1931-07-23
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Granted: 1933-04-18
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Expires: 1951-07-23
Abstract
No abstract record available.
Inventors
- 👤 Chester W Metzgar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:03
CPC Classifications
F; F28; F28F; F28F9/00; F28F9/22; Y; Y10; Y10S; Y10S165/00; Y10S165/355; Y10S165/40; Y10S165/401; Y10S165/416; Y10S165/42; Y10S165/905
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) | 1936-04-17 | 1936-10-17 | 1937-04-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1940-04-17 | 1940-10-17 | 1941-04-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1944-04-17 | 1944-10-17 | 1945-04-18 | $7700.00 | Window Closed / Lapsed |