Patent US3559020A successfully refreshed from Google Patents.
US3559020A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric motor controller device for acceleration and deceleration
Assignee: Hitachi Ltd
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Filing: 1969-08-08
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Granted: 1971-01-26
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Expires: 1989-08-08
Abstract
Abstract A MOTOR CONTROLLER DEVICE COMRISING A MOTOR, IMPEDANCE MEANS FOR CONTROLLING THE ARMATURE CURRENT OF SAID MOTOR, A PLURALITY OF CONTACTOR MEANS SEQUENTIALLY CLOSED TO SHORT-CIRCUIT SAID IMPEDANCE MEANS AT EACH DESIRED SECTION THEREOF, FIELD CONTROL MEANS FOR CONTROLLING THE FIELD CONDITION OF SAID MOTOR, AND CONTROL MEANS FOR OPERATING AFTER A PREDETERMINED NUMBER OF SAID CONTACTOR MEANS ARE CLOSED, SAID FIELD CONTROL MEANS WHEN EACH OF THE REMAINING CONTACTOR MEANS IS CLOSED.
Inventors
- 👤 Fujimaro Imaizumi
- 👤 Tsutomu Ozawa
- 👤 Takasi Tsuboi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 08:31
CPC Classifications
H; H02; H02P; H02P7/00; H02P7/06; H02P7/18; H02P7/24; H02P7/28; H02P7/298; B; B60; B60L; B60L15/00; B60L15/10; B60L15/12; B60L2200/00; B60L2200/26; Y; Y02; Y02T; Y02T10/00; Y02T10/60; Y02T10/64; Y10; Y10S; Y10S388/00; Y10S388/907; Y10S388/917; Y10S388/92
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) | 1974-01-25 | 1974-07-27 | 1975-01-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-25 | 1978-07-27 | 1979-01-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-25 | 1982-07-27 | 1983-01-26 | $7700.00 | Window Closed / Lapsed |