Patent US3520284A successfully refreshed from Google Patents.
US3520284A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Internal combustion engine air intake
Assignee: Dr Ing HCF Porsche AG
•
Filing: 1968-06-03
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Granted: 1970-07-14
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Expires: 1988-06-03
Abstract
No abstract record available.
Inventors
- 👤 Karl Ruoff
- 👤 Leopold Jantschke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 19:37
CPC Classifications
F; F02; F02M; F02M35/00; F02M35/10; F02M35/10091; F02M35/10144; F02B; F02B75/00; F02B75/16; F02B75/18; F02B75/22; F02B75/24; F02B75/243; F02M35/10006; F02M35/10026; F02M35/10039; F02M35/104; F02M35/116; F02M35/1165; F02M35/10209; F02M35/10216; F05; F05C; F05C2225/00; F05C2225/08
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1078919A
Cited
GB283224A
Cited
US2382244A
Cited
US2730339A
Cited
US2871841A
Cited
US2869526A
Cited
US2909165A
Cited
US2916027A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-07-13 | 1974-01-12 | 1974-07-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-07-13 | 1978-01-12 | 1978-07-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-07-13 | 1982-01-12 | 1982-07-14 | $7700.00 | Window Closed / Lapsed |