Patents by Inventor Roy Hartfield

Roy Hartfield 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).

  • Constant torque propeller mechanism
    Patent number: 8790081
    Abstract: A constant torque propeller mechanism allows a propeller to operate very efficiently in both takeoff and cruise flight conditions, which significantly improves aircraft performance. The constant torque propeller mechanism introduces a lightweight and passive propeller control system which requires no electrical power to operate, but at the same time improves the efficiency of the motor propeller combination over the flight envelope.
    Type: Grant
    Filed: November 3, 2008
    Date of Patent: July 29, 2014
    Assignee: Auburn University
    Inventors: Christoph Burger, Roy Hartfield