Patents by Inventor N. Rodger Williamson

N. Rodger Williamson 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: 8884532
    Abstract: An improved lighting control for a luminaire operates an LED luminaire so that its relay opens and closes at or very near the zero current cross-over point so as to reduce the in-rush current to the luminaire, and, if the relay contacts do become stuck, the photo control senses the sticking and electronically vibrates the relay to free its contacts.
    Type: Grant
    Filed: May 25, 2012
    Date of Patent: November 11, 2014
    Assignee: Ripley Lighting Controls, LLC
    Inventors: Richard S. Jones, Dale Thomas, Hal Adair, N. Rodger Williamson, III
  • Publication number: 20130313979
    Abstract: An improved lighting control for a luminaire operates an LED luminaire so that its relay opens and closes at or very near the zero current cross-over point so as to reduce the in-rush current to the luminaire, and, if the relay contacts do become stuck, the photo control senses the sticking and electronically vibrates the relay to free its contacts.
    Type: Application
    Filed: May 25, 2012
    Publication date: November 28, 2013
    Inventors: Richard S. Jones, Dale Thomas, Hal Adair, N. Rodger Williamson, III
  • Patent number: 6218797
    Abstract: A crossing guard maintenance system is disclosed for use with a disabled crossing guard control system. The crossing guard control system has a motor mechanically coupled to a crossing guard arm and a counterweight arm. The motor is used for moving the crossing guard arm between up and down positions. The maintenance system includes a function switch for alternating between normal and maintenance modes of the system. In maintenance mode, a diode is electrically connected to the motor to form a motor/diode circuit that provides a path for current when the polarity of the motor is reversed and it operates as a generator. The maintenance system also includes an electrical power source connected to a momentary switch for providing power to the motor. A method for using the maintenance system is also disclosed for use in repairing a disabled crossing guard mechanism.
    Type: Grant
    Filed: October 1, 1999
    Date of Patent: April 17, 2001
    Assignee: Union Switch & Signal, Inc.
    Inventors: N. Rodger Williamson, Charles R. Drafts
  • Patent number: 5747954
    Abstract: A highway crossing gate control circuit is provided which minimizes the "pumping" oscillation of a highway crossing gate arm which is driven up by a permanent magnet motor. A preferred embodiment of the control circuit utilizes a p-channel MOSFET in a power down module of the control circuit to restrict power from being applied to the motor when the gate arm is in an up position and is intended to be held in the up position by a hold clear device which acts as a mechanical break. Provision is included for dynamic braking on the gate arm moving downward after an initial drive down mode.
    Type: Grant
    Filed: January 30, 1997
    Date of Patent: May 5, 1998
    Assignee: Union Switch & Signal Inc.
    Inventors: Richard S. Jones, N. Rodgers Williamson, Jr.