Method and apparatus for controlling a servo motor using a stepp

Details Method and apparatus for controlling a servo motor using a stepp Method and apparatus for controlling a servo motor using a stepp

1999-02-16

1999-08-10

Ip, Paul

Electricity: motive power systems

Positional servo systems

With particular motor control system responsive to the...

318696, 318687, H02P 800

Patent

active

059363711

ABSTRACT:
An improved DC servo motor driver circuit is provided that is based upon a readily available conventional stepper motor driver integrated circuit (IC). The IC's current "Sense" line that is usually connected to a low value resistor is instead tied to DC common or to ground. The IC's "Comparator" input, which is usually connected to the current Sense line, is connected to a pulsing input signal that provides the comparators with an appropriate voltage to make the comparators believe that more current is required at the very times the remaining portions of the circuit are attempting to provide current to the DC servo motor. An RC circuit is provided at the IC's "Pulse Time" input so that the monostable timer is properly triggered. An ASIC provides the proper logic signals to not only control the direction of the DC servo motor, but also to provide pulses of an appropriate frequency and duty cycle to emulate a pulse-width modulator. The direction signal is connected to the "Phase" input, and the pulse-width modulated signal is provided to interface circuitry that drives the Comparator and Pulse Time inputs. The output transistors in an H-bridge driver stage within the stepper motor driver IC are controlled so as to provide pulse-width modulated voltage pulses across the motor winding of the DC servo motor, such that this DC servo motor can operate exactly as if it were being driven by an integrated circuit that was specifically designed to act as a DC servo motor driver circuit. The average current supplied over time to the DC servo motor is directly related to the duty cycle of the pulse-width modulated voltage pulses across its winding, which in turn is directly related to the duty cycle of the main input control signal.

REFERENCES:
patent: 4084122 (1978-04-01), Gettings
patent: 4176272 (1979-11-01), Powers
patent: 4203678 (1980-05-01), Nordstrom et al.
patent: 4340848 (1982-07-01), Hanagatta et al.
patent: 4412166 (1983-10-01), Crider et al.
patent: 4613806 (1986-09-01), Majewski
patent: 4721896 (1988-01-01), Klinger
patent: 4739346 (1988-04-01), Buckley
patent: 4829222 (1989-05-01), Hallenbeck et al.
patent: 4859923 (1989-08-01), Malka et al.
patent: 5038088 (1991-08-01), Arends et al.
patent: 5087867 (1992-02-01), Kruppa
patent: 5177422 (1993-01-01), Kataoka et al.
patent: 5185627 (1993-02-01), Hartman
patent: 5264770 (1993-11-01), Coutu
patent: 5329214 (1994-07-01), Williamson et al.
patent: 5347300 (1994-09-01), Futagawa
patent: 5708578 (1998-01-01), Stoddard et al.
patent: 5710499 (1998-01-01), Carvajal
patent: 5757398 (1998-05-01), Anderson
patent: 5859518 (1999-01-01), Vitunic

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