Patents by Inventor Richard T. Rocheleau

Richard T. Rocheleau 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: 4243843
    Abstract: A method and apparatus for determining graphical coordinates includes a grid of parallel spaced conductors, a switch in series with each conductor, a cursor having an alternating magnetic field for inducing an electric current in conductors over which it is passed and means for selectively closing the conductor switches to enable induced current flow in only one conductor at a time. The change of phase of current between conductors on either side of the cursor resulting from a circular magnetic field is detected for registering a count in a counter indicative of a coarse cursor distance from an origin axis. A count equal to a fine measurement of the distance of the cursor from a proximate conductor is added to the coarse distance count to derive a graphic coordinate.
    Type: Grant
    Filed: February 22, 1979
    Date of Patent: January 6, 1981
    Assignee: Summagraphics Corporation
    Inventor: Richard T. Rocheleau