Patents by Inventor Leonard William Kingswell

Leonard William Kingswell 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).

  • Data transmission system between telephone subscriber location and telephone exchange location during idle telephone condition
    Patent number: 4059727
    Abstract: An electrical data transmission system employs a telephone line to transmit data from a subscriber data equipment to a telephone exchange data equipment when the telephone line is idle. A first idle line sensing means is associated with the subscriber equipment and is operable to connect the line to the subscriber equipment when the line is idle and to disconnect the line from the subscriber equipment when the line is busy. A second idle line sensing means is associated with the exchange data equipment and is operable to connect the line to the exchange equipment when the line is idle and to disconnect the line from the exchange equipment when the line is busy.
    Type: Grant
    Filed: January 3, 1977
    Date of Patent: November 22, 1977
    Assignee: The Post Office
    Inventors: Leonard William Kingswell, Oliver Charles Matthews