Patent US2771329A successfully refreshed from Google Patents.
US2771329A
Expired / Lapsed
US
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Composite piston ring
Assignee: Wilkening Manufacturing Co
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Filing: 1951-01-24
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Granted: 1956-11-20
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Expires: 1971-01-24
Abstract
No abstract record available.
Inventors
- 👤 Helmuth G Braendel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 22:51
CPC Classifications
F; F16; F16J; F16J9/00; F16J9/06; F16J9/061; F16J9/063
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US1359596A
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US1422780A
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GB520351A
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US2229578A
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US2235297A
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US2293450A
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GB560783A
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US2468980A
Cited
US2564744A
Cited
US2639205A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-11-20 | 1960-05-21 | 1960-11-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-11-20 | 1964-05-21 | 1964-11-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-11-20 | 1968-05-21 | 1968-11-20 | $7700.00 | Window Closed / Lapsed |