Patents by Inventor Dexter Smith

Dexter 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).

  • Electronic cancellation of DC motor noise
    Patent number: 6259224
    Abstract: An active attenuation system for a DC motor which yields global vibration reduction of slot or other motor induced tonals at the plate on which the motor is mounted without modifying the construction of the motor. The system comprises one or more vibration sensors, a signal synchronized to the slot rate or other motor induced tonal rate, an electronic adaptive controller and the means to supply the control signal into the motor field and/or armature current.
    Type: Grant
    Filed: October 18, 1996
    Date of Patent: July 10, 2001
    Assignee: Noise Cancellation Technologies, Inc.
    Inventors: Dexter Smith, Joseph Schwartz, Eldon W. Ziegler, Jr.
  • Low cost controller
    Patent number: 5627746
    Abstract: A simple, low cost active noise cancellation system employing a delay and actuator estimator (35), a gain determination (34), a gain (33) and speaker (36) that cancels stationary random noise such as that encountered on a rangehood fan.
    Type: Grant
    Filed: March 1, 1995
    Date of Patent: May 6, 1997
    Assignee: Noise Cancellation Technologies, Inc.
    Inventors: Eldon W. Ziegler, Jr., Dexter Smith, Michael P. McLoughlin