Patents by Inventor Joseph L. Tyrrell

Joseph L. Tyrrell 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).

  • Electrostatic tablet writing stylus
    Patent number: 4158747
    Abstract: An improved device for capacitively detecting signals generated in a writing table by a grid of conductive wires that produce a varying electrostatic field near its surface to be picked up through a stack of paper with the table functioning as one plate of a capacitor, and a conductive stylus as the other plate. The improvement consists of grounding the stylus, which has an extended body portion surrounded by a tubular member, extending the tubular member to a point very near the stylus tip where it functions as the second plate of a capacitor, and connecting the tubular member to a preamplifier mounted in the device.
    Type: Grant
    Filed: June 26, 1978
    Date of Patent: June 19, 1979
    Assignee: Telautograph Corporation
    Inventors: Alex M. Muller, Joseph L. Tyrrell
  • Memo transmitter
    Patent number: D244036
    Type: Grant
    Filed: May 4, 1976
    Date of Patent: April 12, 1977
    Assignee: Telautograph Corporation
    Inventor: Joseph L. Tyrrell