Patent US2500837A successfully refreshed from Google Patents.
Patent US2820339A successfully refreshed from Google Patents.
US2820339A
Expired / Lapsed
US
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Turbo-charged internal combustion engines and methods of starting and operating them
Assignee: Nordberg Manufacturing Co
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Filing: 1952-03-31
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Granted: 1958-01-21
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Expires: 1972-03-31
Abstract
No abstract record available.
Inventors
- 👤 Grieshaber Emil
- 👤 Paul S Shirley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 07:46
CPC Classifications
F; F01; F01L; F01L13/00; F01L13/0015; F01L9/00; F01L9/10; F01L9/11; F02; F02D; F02D23/00; F16; F16L; F16L13/00; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2067288A
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US2097883A
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US2090877A
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US2281987A
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US2401188A
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US2444644A
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US2578028A
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US2602434A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-01-20 | 1961-07-22 | 1962-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-01-20 | 1965-07-22 | 1966-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-01-20 | 1969-07-22 | 1970-01-21 | $7700.00 | Window Closed / Lapsed |