Thomas Milton Horning

US Patent:

42141940, Jul 22, 1980

Filed:

Dec 2, 1977

Appl. No.:

5/856649

Inventors:

Thomas Horning - San Fernando CA

Assignee:

Data Products Corporation - Woodland Hills CA

International Classification:

H02K 3700

US Classification:

318696

Abstract:

A method for driving stepping motors, typically used in digital hard copy printers, can be employed wherein the phased stator coils of the stepping motor are energized in an overlapping relationship. In addition, the voltage or current applied to the stator coils in a stepping motor may be driven in a pulsed manner such that certain portions of the energized duration are characterized by a higher driving current or voltage. By virtue of the simultaneous activation of the adjacent phases of the stator coils, quasi-equilibrium positions may be created between the equilibrium positions in a stepping motor with the result that a smoother and more uniform angular accelerations and decelerations can be obtained. Circuitry conducive to a digital application to practice the method of the present invention employs a multiple bit shift register driven by a decoder and which in turn drives a plurality of operational amplifiers. Another operational amplifier coupled to the decoder provides a controlled current source.