Patent US3048991A successfully refreshed from Google Patents.
US3548472A
Expired / Lapsed
US
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Ignition plug and method for manufacturing a center electrode for the same
Assignee: Hitachi Ltd
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Filing: 1968-11-14
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Granted: 1970-12-22
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Expires: 1988-11-14
Abstract
No abstract record available.
Inventors
- 👤 Hisashi Urushiwara
- 👤 Hiroshi Morino
- 👤 Misao Suzuki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 16:26
CPC Classifications
H; H01; H01T; H01T21/00; H01T21/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2208030A
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US2296033A
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US2321840A
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US2360287A
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US2415138A
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US2717438A
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US2449403A
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US2542903A
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US3356882A
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US3452235A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-12-21 | 1974-06-22 | 1974-12-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-12-21 | 1978-06-22 | 1978-12-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-12-21 | 1982-06-22 | 1982-12-22 | $7700.00 | Window Closed / Lapsed |