Patent US4574228A successfully refreshed from Google Patents.
US4574228A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Current controlled motor drive circuit
Assignee: International Business Machines Corp
•
Filing: 1984-12-07
•
Granted: 1986-03-04
•
Expires: 2004-12-07
Abstract
Abstract A switching regulator causes a supply voltage to be intermittently chopped to provide energy pulses in a lowpass filter circuit. The lowpass filter circuit includes a capacitor which is being charged by the chopped energy pulses and whose output is used to drive a low voltage stepper motor. The duty cycle of the energy pulses is a function of the average value of the stepper motor coil current. By correlating the duty cycle of the energy pulses with the average current in the motor coil a relatively high torque is provided to drive the motor during a startup phase and is automatically adjusted to meet the running requirements of the particular stepper motor.
Inventors
- 👤 Larry A. Blue
- 👤 David E. Conner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 12:41
CPC Classifications
H; H02; H02P; H02P8/00; H02P8/04; H02P8/10; H02P8/12
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
130 words
A circuit arrangement for driving a motor comprising: first means operable for generating a DC voltage signal; a chopper circuit means operable for correlating the voltage signal with an input drive signal and to output a modified DC voltage signal whose on-to-off time ratio is being dictated by a duty cycle of the input drive signal; a filtering means operable for averaging the modified DC voltage signal and for supplying the averaged voltage signal to the motor; a second means coupled to said motor and operable for monitoring current flow therethrough and for providing an error signal representative of said current; and a third means responsive to the error signal and operable to generate and output the input drive signal whose duty cycle is being controlled by the error signal.
Claim 2
Dependent Claim
130 words
A circuit arrangement for driving a motor comprising: first means operable for generating a DC voltage signal; a chopper circuit means operable for correlating the voltage signal with an input drive signal and to output a modified DC voltage signal whose on-to-off time ratio is being dictated by a duty cycle of the input drive signal; a filtering means operable for averaging the modified DC voltage signal and for supplying the averaged voltage signal to the motor; a second means coupled to said motor and operable for monitoring current flow therethrough and for providing an error signal representative of said current; and a third means responsive to the error signal and operable to generate and output the input drive signal whose duty cycle is being controlled by the error signal.
Claim 3
Dependent Claim
28 words
The circuit arrangement of claim 1 wherein the error signal generated by the second means represents the average value of current flowing in the windings of said motor.
Claim 4
Dependent Claim
176 words
A circuit arrangement for driving a motor comprising: first means operable for generating a DC voltage signal; a chopper circuit means, including a switching transistor, a diode being connected to the collector lead of said transistor a first resistor being connected to the base lead and a second resistor interconnecting the emitter lead to the base lead, with said chopper circuit means being operable for correlating the voltage signal with an input drive signal and to output a modified DC voltage signal whose on-to-off time ratio is being dictated by a duty cycle of the input drive signal; a filtering means operable for averaging the modified DC voltage signal and for supplying the averaged voltage signal to the motor; a second means coupled to said motor and operable for monitoring current flow therethrough and for providing an error signal representative of the average value of said current; and a third means responsive to the error signal and operable to generate and output the input drive signal whose duty cycle is being controlled by the error signal.
Claim 5
Dependent Claim
176 words
A circuit arrangement for driving a motor comprising: first means operable for generating a DC voltage signal; a chopper circuit means, including a switching transistor, a diode being connected to the collector lead of said transistor a first resistor being connected to the base lead and a second resistor interconnecting the emitter lead to the base lead, with said chopper circuit means being operable for correlating the voltage signal with an input drive signal and to output a modified DC voltage signal whose on-to-off time ratio is being dictated by a duty cycle of the input drive signal; a filtering means operable for averaging the modified DC voltage signal and for supplying the averaged voltage signal to the motor; a second means coupled to said motor and operable for monitoring current flow therethrough and for providing an error signal representative of the average value of said current; and a third means responsive to the error signal and operable to generate and output the input drive signal whose duty cycle is being controlled by the error signal.
Claim 6
Dependent Claim
21 words
The circuit arrangement of claim 1 wherein the filtering means includes an inductive coil being connected in series with a capacitor.
Claim 7
Dependent Claim
20 words
The circuit arrangement of claim 1 wherein the second means includes integrating means for integrating the current through the windings.
Claim 8
Dependent Claim
20 words
The circuit arrangement of claim 5 wherein the integrating means includes a resistive means connected in parallel with a capacitor.
Claim 9
Dependent Claim
15 words
The circuit arrangement of claim 1 wherein the third means includes a pulse width modulator.
Claim 10
Dependent Claim
153 words
An improved circuit arrangement for adjusting the volage generated from a power supply and providing a controlled signal for energizing the coils of a stepper motor, said improved circuit arrangement comprising; first means for monitoring current flowing through the coils and for generating a signal representative of said current; second means responsive to said signal and operable for generating a second signal with variable duty cycle; chopper circuit means connected to the power supply and operable for correlating the signal outputted from said power supply with the second signal to provide a chopped DC voltage signal whose on-off time ratio is being dictated by the second signal with variable duty cycle; and means operable for processing the chopped DC voltage signal and to store an adjustable charge operable for supplying a high torque for initiating motion in said motor and for supplying a lower torque when motion is being established in said motor.
Claim 11
Dependent Claim
153 words
An improved circuit arrangement for adjusting the volage generated from a power supply and providing a controlled signal for energizing the coils of a stepper motor, said improved circuit arrangement comprising; first means for monitoring current flowing through the coils and for generating a signal representative of said current; second means responsive to said signal and operable for generating a second signal with variable duty cycle; chopper circuit means connected to the power supply and operable for correlating the signal outputted from said power supply with the second signal to provide a chopped DC voltage signal whose on-off time ratio is being dictated by the second signal with variable duty cycle; and means operable for processing the chopped DC voltage signal and to store an adjustable charge operable for supplying a high torque for initiating motion in said motor and for supplying a lower torque when motion is being established in said motor.
Claim 12
Dependent Claim
104 words
A circuit arrangement for driving a motor comprising: first means operable for generating a DC voltage signal; a chopper circuit means operable for correlating the voltage signal with an input drive signal and to output a modified DC voltage signal; a filtering means operable for averaging the modified DC voltage signal and for supplying the averaged voltage signal to the motor; a second means coupled to said motor and operable for monitoring current flow therethrough and for providing an error signal representative of said current; and a third means responsive to the error signal and operable to generate and output the input drive signal.
Claim 13
Dependent Claim
104 words
A circuit arrangement for driving a motor comprising: first means operable for generating a DC voltage signal; a chopper circuit means operable for correlating the voltage signal with an input drive signal and to output a modified DC voltage signal; a filtering means operable for averaging the modified DC voltage signal and for supplying the averaged voltage signal to the motor; a second means coupled to said motor and operable for monitoring current flow therethrough and for providing an error signal representative of said current; and a third means responsive to the error signal and operable to generate and output the input drive signal.
References Cited (Backward Citations)
US3742330A
Cited
US4431955A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-03-03 | 1989-09-02 | 1990-03-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-03-03 | 1993-09-02 | 1994-03-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-03-03 | 1997-09-02 | 1998-03-04 | $7700.00 | Window Closed / Lapsed |