Patents by Inventor Jack Nordquist

Jack Nordquist 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).

  • Passive electronic damping for step motor
    Patent number: 6040676
    Abstract: Passive electronic damping apparatus for a step motor of the type having a number of phase windings, comprising: a respective transconductance amplifier coupled to each phase winding for producing a phase drive current in the winding in response to a position command; each transconductance amplifier exhibiting an output impedance characteristic; and a circuit for changing the amplifier output impedance to effect motor damping.
    Type: Grant
    Filed: January 22, 1997
    Date of Patent: March 21, 2000
    Assignee: Parker-Hannifin Corporation
    Inventors: Jack Nordquist, Mark J. Calahan, Timothy J. Damiano, Christopher M. Botka
  • Active electronic damping for step motor
    Patent number: 5847535
    Abstract: Apparatus for electronically producing a torque dependent signal for a plural drive phase synchronous step motor, without the use of an accelerometer or other external feedback device, includes a circuit for detecting respective instantaneous terminal voltage signals for at least two phases of the motor; another circuit for detecting respective instantaneous phase current signals for said at least two phases; and a signal processing circuit for combining the detected signals to produce said torque dependent signal.
    Type: Grant
    Filed: January 22, 1997
    Date of Patent: December 8, 1998
    Assignee: Parker-Hannifin Corporation
    Inventors: Jack Nordquist, Mark C. Calahan, Timothy J. Damiano, Christopher M. Botka