Patents by Inventor Donald Hammond Rist

Donald Hammond Rist 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).

  • Speed control for electrically propelled traction vehicles
    Patent number: 4012677
    Abstract: An electrical propulsion control system for self-propelled traction vehicles of the type having a prime mover-driven electric generator supplying energy to traction motors and regulating means for maintaining the electrical output of the generator within desired limits, wherein the limit of generator output voltage is varied between zero and a predetermined maximum level as a function of desired vehicle speed.
    Type: Grant
    Filed: February 27, 1975
    Date of Patent: March 15, 1977
    Assignee: General Electric Company
    Inventors: Donald Hammond Rist, Barry Jay Turley
  • Prime mover speed responsive load control for electrically propelled traction vehicles
    Patent number: 3970858
    Abstract: An electrical propulsion control system for self-propelled traction vehicles of the type having a thermal prime mover-driven electric generator supplying energy to traction motors, wherein the electrical output of the generator is regulated within predetermined maximum voltage, current, and power limits and is independently reduced, without reducing the voltage or current limit, in response to the prime mover decelerating to speeds at which it is subject to bogging.
    Type: Grant
    Filed: February 27, 1975
    Date of Patent: July 20, 1976
    Assignee: General Electric Company
    Inventors: Donald Hammond Rist, Barry Jay Turley