Patents by Inventor Robert C. B. Smith

Robert C. B. Smith has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4985669
    Abstract: A multi-phase stepper motor in which one or more salient sensor poles and corresponding pick-up windings are employed to sense the actual position of the rotor. The rotor is of annular configuration and includes a first set of nonsalient rotor poles around its outer periphery and a second set of nonsalient rotor poles around its inner periphery, with the outer rotor poles being in magnetic flux relationship with the motor's stator poles and the inner rotor poles being in magnetic flux relationship with the sensor poles. A cylindrical housing of magnetic material surrounds the motor. An energizing circuit is provided to apply successive direct current pulses to the stator windings of the motor, and the pick-up windings are connected in a feedback circuit to adjust the applied pulses in accordance with the desired position of the rotor.
    Type: Grant
    Filed: July 13, 1989
    Date of Patent: January 15, 1991
    Assignee: Tri-Tech Inc.
    Inventor: Robert C. B. Smith