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US2974387A
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Tunnel kiln and continuous conveyor system
Assignee: Shenango China Inc
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Filing: 1958-04-21
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Granted: 1961-03-14
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Expires: 1978-04-21
Abstract
No abstract record available.
Inventors
- 👤 David E Tomkins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:35
CPC Classifications
F; F27; F27B; F27B9/00; F27B9/14; F27B9/20; F27B9/24; F27B9/243
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1630587A
Cited
US1271752A
Cited
US1636073A
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US1678251A
Cited
GB327486A
Cited
US2041176A
Cited
US2342440A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-03-13 | 1964-09-12 | 1965-03-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-03-13 | 1968-09-12 | 1969-03-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-03-13 | 1972-09-12 | 1973-03-14 | $7700.00 | Window Closed / Lapsed |