Patents by Inventor Thomas Derek Lindon

Thomas Derek Lindon 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).

  • Hydraulic actuator controls
    Patent number: 4031813
    Abstract: A device for controlling a hydraulic actuator comprises two servo loops having in common a fluid pressure operated main valve and an electrically operated pilot valve for controlling the main valve. One of the servo loops is for flow control and contains a flow transducer for producing an electrical feedback signal responsively to fluid flow to the actuator and a comparator for comparing the flow feedback signal with a first electrical input signal. The other servo loop is for force control and contains pressure transducing means for producing an electrical feedback signal responsively to the pressure drop across the actuator and a second comparator for comparing the force feedback signal with a second electrical input signal.
    Type: Grant
    Filed: October 3, 1974
    Date of Patent: June 28, 1977
    Assignee: Sperry Rand Limited
    Inventors: Ronald Bernard Walters, Peter Michael Hamey, John Anthony Gordon Hammond, Thomas Derek Lindon