Patent US4298996A successfully refreshed from Google Patents.
Patent US2037880A successfully refreshed from Google Patents.
US2037880A
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Assignee: HARTZELL INDUSTRIES
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Filing: 1933-11-17
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Granted: 1936-04-21
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Expires: 1953-11-17
Abstract
No abstract record available.
Inventors
- 👤 Charavay Frederick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:36
CPC Classifications
F; F04; F04D; F04D29/00; F04D29/26; F04D29/28; F04D29/281; F04D29/282
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) | 1939-04-21 | 1939-10-21 | 1940-04-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1943-04-21 | 1943-10-21 | 1944-04-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1947-04-21 | 1947-10-21 | 1948-04-21 | $7700.00 | Window Closed / Lapsed |