Patent US4064443A successfully refreshed from Google Patents.
US4064443A
Expired / Lapsed
US
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Control system for D.C. motor
Assignee: Ricoh Co Ltd
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Filing: 1975-12-02
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Granted: 1977-12-20
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Expires: 1995-12-02
Abstract
Abstract In the control system, the motor is supplied power in the form of a pulse train. The width of each pulse of the pulse train is modulated through the comparison between a reference voltage and the counter e.m.f. of the motor immediately prior to feeding of each pulse of the pulse train into the motor.
Inventors
- 👤 Isao Yamada
- 👤 Isamu Shibata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 10:57
CPC Classifications
H; H02; H02P; H02P7/00; H02P7/06; H02P7/18; H02P7/24; H02P7/28; H02P7/285; H02P7/29; H02P7/291; Y; Y10; Y10S; Y10S388/00; Y10S388/907; Y10S388/915
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
146 words
A control system, for a d.c. motor supplied by a pulse train, comprising, in combination, generating means generating a first pulse train; differentiating means differentiating said first pulse train to produce a trigger pulse train; means, responsive to each pulse of said trigger pulse train and to a respective control signal, producing respective pulses which, together, constitute a second pulse train for supply to the motor; a reference voltage source; means comparing the reference voltage and the counter e.m.f. of the motor, prior to feeding each pulse of said second pulse train into the motor, to produce said control signal, AND gate means having an output connected to the motor; a first input connected to said generating means, and a second input; and an inverter having an input connected to said producing means and an output connected to said second input of said AND gate means.
Claim 2
Dependent Claim
146 words
A control system, for a d.c. motor supplied by a pulse train, comprising, in combination, generating means generating a first pulse train; differentiating means differentiating said first pulse train to produce a trigger pulse train; means, responsive to each pulse of said trigger pulse train and to a respective control signal, producing respective pulses which, together, constitute a second pulse train for supply to the motor; a reference voltage source; means comparing the reference voltage and the counter e.m.f. of the motor, prior to feeding each pulse of said second pulse train into the motor, to produce said control signal, AND gate means having an output connected to the motor; a first input connected to said generating means, and a second input; and an inverter having an input connected to said producing means and an output connected to said second input of said AND gate means.
References Cited (Backward Citations)
US3488756A
Cited
US3588654A
Cited
US3683253A
Cited
US3783360A
Cited
US3694721A
Cited
US3883786A
Cited
US3976926A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-12-19 | 1981-06-20 | 1981-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-12-19 | 1985-06-20 | 1985-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-12-19 | 1989-06-20 | 1989-12-20 | $7700.00 | Window Closed / Lapsed |