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US3420052A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Combination exhaust muffler and heater
Assignee: Boeing North American Inc
•
Filing: 1967-03-08
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Granted: 1969-01-07
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Expires: 1987-03-08
Abstract
No abstract record available.
Inventors
- 👤 Frank S Miller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 17:34
CPC Classifications
F; F01; F01N; F01N5/00; F01N5/02; F01N1/00; F01N1/08; F02; F02M; F02M1/00; F02M2700/00; F02M2700/43; F02M2700/4302; F02M2700/434; F02M2700/4342; F02M2700/4345; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2618355A
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US2361133A
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US2541973A
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US2940249A
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US2833368A
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US2878888A
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US3043098A
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US3189122A
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US3375898A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-01-07 | 1972-07-08 | 1973-01-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-01-07 | 1976-07-08 | 1977-01-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-01-07 | 1980-07-08 | 1981-01-07 | $7700.00 | Window Closed / Lapsed |