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US1220486A
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US
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Self-excited direct-current dynamo-electric machinery.
Assignee: BBC Brown Boveri AG Switzerland
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Filing: 1912-02-12
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Granted: 1917-03-27
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Expires: 1932-02-12
Abstract
No abstract record available.
Inventors
- 👤 Paul Amsler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 16:46
CPC Classifications
H; H02; H02K; H02K21/00; H02K21/12; H02K21/22
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1920-03-26 | 1920-09-25 | 1921-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1924-03-26 | 1924-09-25 | 1925-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1928-03-26 | 1928-09-25 | 1929-03-27 | $7700.00 | Window Closed / Lapsed |