Patents by Inventor John Paul Buchanan

John Paul Buchanan 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: 4109185
    Abstract: A servo system, particularly well suited for use in a computerized numerical control system for a large machine tool, in which a plurality of axis controlling servo circuits are controlled by one computerized axis controller. As each controlled axis moves, an attached resolver's output is digitized to generate a digital position feedback signal which is compared to the desired position in the computer. The resultant error signal is converted to an analog voltage to control said axis motion. A digital clock and counter drives two digital to analog converters to create the two resolver inputs, and supplies timing signals to the computer, thus synchronizing the system.
    Type: Grant
    Filed: December 27, 1976
    Date of Patent: August 22, 1978
    Assignee: McDonnell Douglas Corporation
    Inventors: Stanley G. Froyd, Raymond C. Ue, John Paul Buchanan