Patent US2521699A successfully refreshed from Google Patents.
US2521699A
Expired / Lapsed
US
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Heat-treating gear
Assignee: Ohio Crankshaft Co
•
Filing: 1946-03-05
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Granted: 1950-09-12
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Expires: 1966-03-05
Abstract
No abstract record available.
Inventors
- 👤 Francis S Denneen
- 👤 William C Dunn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 04:00
CPC Classifications
C; C21; C21D; C21D9/00; C21D9/32
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1878458A
Cited
GB416928A
Cited
DE630844C
Cited
GB445425A
Cited
US2240494A
Cited
US2067549A
Cited
US2178201A
Cited
US2398085A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-09-11 | 1954-03-13 | 1954-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-09-11 | 1958-03-13 | 1958-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-09-11 | 1962-03-13 | 1962-09-12 | $7700.00 | Window Closed / Lapsed |