Stepper motor control circuit
AssigneeBeloit Corporation
InventorRoger C. Brendemuehl
Life of this patent
Estimating the term…
Abstract
A stepper motor control circuit for a step motor and step motor control which has substantially higher efficiency than the motors and the control circuits of the prior art and which uses a chopper current control and phase control for each of the two phases of a two phase step motor and wherein each phase has two separate windings that are magnetically coupled together. The invention provides a three step switching sequence which produces different current paths in each step so that a higher operating efficiency is achieved than circuits in the prior art.
Claims13
A stepper motor control circuit for a stepper motor having at least a single phase comprising a pair of windings magnetically coupled together and joined together at first ends thereof, a direct current motor power supply with one terminal connected to a reference potential, a first electronic switch connected between the other terminal of said motor power supply and said first ends of said pair of windings, a chopper control connected to said first electronic switch to control it, a first resistor with one side connected to said reference potential, a second electronic switch connected between the second end of one of said pair of windings and the second side of said first resistor, a third electronic switch connected between said second end of said first resistor and the second end of the second of said pair of windings, a phase switching control receiving input step pulses connected to said second and third electronic switches to turn them on and off and a sensing circuit connected to said second electronic switch and said first resistor so as to sense the voltage drop across said first resistor and supplying an output to said chopper control, a second resistor connected between said reference potential and the second end of the second of said pair of windings.
Dependencies are inferred from the claim text.