Patent US3697844A successfully refreshed from Google Patents.
US3697844A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Full wave dc motor control
Assignee: General Electric Co
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Filing: 1970-07-28
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Granted: 1972-10-10
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Expires: 1990-07-28
Abstract
Abstract A motor control circuit for use with a direct current motor. The control circuit includes means for generating and comparing a signal representative of the actual speed of the motor and a reference signal which has a component thereof indicative of the IR voltage of the armature and which further takes into account the field weakening effect of direct current motors to provide complete IR compensation over the entire range of motor speeds.
Inventors
- 👤 Edward H Dinger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 10:02
CPC Classifications
H; H02; H02P; H02P7/00; H02P7/06; H02P7/18; H02P7/24; H02P7/28; H02P7/285; H02P7/292; H02P7/293; Y; Y10; Y10S; Y10S388/00; Y10S388/90; Y10S388/902; Y10S388/903
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
153 words
A control for a motor having an armature comprising means for energIzing the armature of said motor from an alternating voltage source by means controlling the periods of conductivity of a current from said source through said armature, means for providing a reference voltage which is adjustable to an initial value proportional to a desired motor speed, means for sensing and providing a speed voltage representative of the instantaneous speed of said armature, means for comparing said sensed speed voltage and said reference voltage to provide a control signal, means to modify the speed of the motor in accordance with said control signal, and means to provide compensation for the differing effect of armature IR voltage drop at differing motor speeds comprising means for modifying said reference voltage from said initial value to a final value as a function of both said armature current and said initial adjusted value of said reference voltage.
Claim 2
Dependent Claim
153 words
A control for a motor having an armature comprising means for energIzing the armature of said motor from an alternating voltage source by means controlling the periods of conductivity of a current from said source through said armature, means for providing a reference voltage which is adjustable to an initial value proportional to a desired motor speed, means for sensing and providing a speed voltage representative of the instantaneous speed of said armature, means for comparing said sensed speed voltage and said reference voltage to provide a control signal, means to modify the speed of the motor in accordance with said control signal, and means to provide compensation for the differing effect of armature IR voltage drop at differing motor speeds comprising means for modifying said reference voltage from said initial value to a final value as a function of both said armature current and said initial adjusted value of said reference voltage.
Claim 3
Dependent Claim
24 words
Apparatus according to claim 1 wherein said means for providing an adjustable reference voltage comprises a voltage divider whose setting determines the adjustment value.
Claim 4
Dependent Claim
54 words
Apparatus according to claim 2 wherein said means for providing an adjustable reference voltage comprises a potentiometer connected across a source of constant, unidirectional voltage through a circuit providing a voltage signal proportional to armature current and means for applying the signal developed at the movable tap of said potentiometer to said comparing means.
Claim 5
Dependent Claim
38 words
Apparatus as defined in claim 1 and further including means to synchronize the activation of said means for modifying the periods of conductivity of current through such armature with a zero voltage point of such alternating voltage source.
Claim 6
Dependent Claim
46 words
Apparatus as defined in claim 4 and further including means to delay the activation of said means for modifying the periods of conductivity of current through such armature for a predetermined number of electrical degrees after said zero voltage crossing point of such alternating voltage source.
Claim 7
Dependent Claim
30 words
Apparatus as defined in claim 5 and including means for limiting the current flow through such armature and interrupting said current flow upon said current flow exceeding a predetermined value.
Claim 8
Dependent Claim
61 words
Apparatus as defined in claim 6 and wherein said means for comparing the sensed speed voltage and the reference signal is a transistor having an emitter, a base and a collector, said speed voltage being applied to the emitter of said transistor, said reference voltage being applied to the base of said transistor and the control signal appearing at said collector.
Claim 9
Dependent Claim
25 words
Apparatus as defined in claim 7 and wherein said means for controlling the periods of conductivity of current through such armature includes a controlled rectifier.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-10-10 | 1976-04-10 | 1976-10-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-10 | 1980-04-10 | 1980-10-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-10 | 1984-04-10 | 1984-10-10 | $7700.00 | Window Closed / Lapsed |