Patent US3187189A successfully refreshed from Google Patents.
US3187189A
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Contrarotating hydroelectric machines including two synchronous generators
Assignee: Library and Archives Canada
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Filing: 1962-11-20
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Granted: 1965-06-01
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Expires: 1982-11-20
Abstract
No abstract record available.
Inventors
- 👤 Johann H Lang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:34
CPC Classifications
F; F03; F03B; F03B15/00; H; H02; H02K; H02K7/00; H02K7/18; H02K7/1807; H02K7/1823; H02P; H02P23/00; H02P23/16; Y; Y02; Y02E; Y02E10/00; Y02E10/20
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
87 words
IN COMBINATION, A HYDROELECTRIC MACHINE HAVING CONTRAROTATING, AXIAL FLOW, COAXIAL WATER WHEELS OPERATING IN CLOSELY SPACED AXIAL RELATION IN A COMMON WATER STREAM AND A SHAFT EACH WATER WHEEL FOR DRIVING THE MACHINE, AND MEANS FOR CONTROLLING THE TORQUE RATIO OF SAID SHAFTS, AT LEAST ONE OF SAID WATER WHEELS HAVING VARIABLE PITCH BLADES, SAID TORQUE CONTROL MEANS COMPRISING MEANS FOR OBTAINING FOR EACH SHAFT A SIGNAL REPRESENTING THE TORQUE DEVELOPED THEREIN, MEANS FOR COMPRISING SAID SIGNALS TO OBTAIN A CONTROL SIGNAL REPRESENTING THE DIFFERENCE OF SAID
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-05-31 | 1968-11-30 | 1969-06-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-05-31 | 1972-11-30 | 1973-06-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-05-31 | 1976-11-30 | 1977-06-01 | $7700.00 | Window Closed / Lapsed |