Patent US3057222A successfully refreshed from Google Patents.
Patent US3199008A successfully refreshed from Google Patents.
US3199008A
Expired / Lapsed
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Plural motor speed control by armature variation and relative load control
Assignee: Harnischfeger Corp
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Filing: 1961-09-01
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Granted: 1965-08-03
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Expires: 1981-09-01
Abstract
No abstract record available.
Inventors
- 👤 David W Stone
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 19:39
CPC Classifications
B; B66; B66C; B66C13/00; B66C13/18; B66C13/22; B66C13/23; B66C13/24; B66C13/52; B66C13/54; B66C2700/00; B66C2700/08; B66C2700/085; B66C2700/087
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
95 words
CONTROL APPARATUS FOR CONTROL OF THE SPEEDS OF TWO ELECTRIC MOTORS HAVING FIXED FIELD CIRCUITS AND VARIABLE ARMATURE CIRCUITS COMPRISING: FIRST AND SECOND ARMATURE POWER SUPPLY CIRCUITS FOR SAID FIRST AND SECOND MOTORS; FIRST AND SECOND SOURCES OF CONTROL SIGNAL VOLTAGE FOR SAID CIRCUITS, SAID CIRCUITS COMPRISING MEANS FOR SUBSTANTIALLY UNIFORMLY AFFECTING THE ARMATURE CIRCUITS AND THE ABSOLUTE SPEEDS OF BOTH MOTORS IN RESPONSE TO A SIGNAL FROM SAID FIRST SOURCE AND FOR DIFFERENTIALLY AFFECTING THE ARMATURE CIRCUITS AND THE ABSOLUTE SPEEDS OF BOTH MOTORS IN RESPONSE TO A SIGNAL FROM SAID SECOND SOURCE; AND
Claim 2
Dependent Claim
95 words
CONTROL APPARATUS FOR CONTROL OF THE SPEEDS OF TWO ELECTRIC MOTORS HAVING FIXED FIELD CIRCUITS AND VARIABLE ARMATURE CIRCUITS COMPRISING: FIRST AND SECOND ARMATURE POWER SUPPLY CIRCUITS FOR SAID FIRST AND SECOND MOTORS; FIRST AND SECOND SOURCES OF CONTROL SIGNAL VOLTAGE FOR SAID CIRCUITS, SAID CIRCUITS COMPRISING MEANS FOR SUBSTANTIALLY UNIFORMLY AFFECTING THE ARMATURE CIRCUITS AND THE ABSOLUTE SPEEDS OF BOTH MOTORS IN RESPONSE TO A SIGNAL FROM SAID FIRST SOURCE AND FOR DIFFERENTIALLY AFFECTING THE ARMATURE CIRCUITS AND THE ABSOLUTE SPEEDS OF BOTH MOTORS IN RESPONSE TO A SIGNAL FROM SAID SECOND SOURCE; AND
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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) | 1968-08-02 | 1969-02-01 | 1969-08-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-08-02 | 1973-02-01 | 1973-08-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-08-02 | 1977-02-01 | 1977-08-03 | $7700.00 | Window Closed / Lapsed |