Patent US2672813A successfully refreshed from Google Patents.
US2672813A
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Method of firing electric detonators and circuit therefor
Assignee: Hercules Powder Co
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Filing: 1948-04-01
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Granted: 1954-03-23
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Expires: 1968-04-01
Abstract
No abstract record available.
Inventors
- 👤 Willard P Conner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:16
CPC Classifications
F; F42; F42D; F42D1/00; F42D1/04; F42D1/045; F42D1/05
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1310568A
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US730246A
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US850972A
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US1133183A
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US1757288A
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US1769203A
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GB590489A
Cited
US2448020A
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US2493662A
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US2474335A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-03-22 | 1957-09-21 | 1958-03-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-03-22 | 1961-09-21 | 1962-03-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-03-22 | 1965-09-21 | 1966-03-23 | $7700.00 | Window Closed / Lapsed |