Patents by Inventor Marshall Daly

Marshall Daly 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: 4628153
    Abstract: A stand-alone keyphone system that is designed to be installed at any location where it is desired that a plurality of telephone lines be available to each of many user points. The system operates independently of all other systems and without the need for a KSU or a central control unit. Each system allows a plurality of telephone lines to be connected and operated simultaneously and a plurality of systems may be connected within each installation with minimal loading of telephone lines. The system comprises, within a single housing, a DTMF telephone set and a key adapter set that further comprises all the mechanical and electronic circuits to operate the system including a switching subsystem and hold circuit subsystem. The system incorporates a hold pushbutton for placing any of the telephone lines on hold, a set of four telephone line accessing pushbuttons; and a set of line status LED's that indicate if the corresponding line is idle, ringing, busy or holding.
    Type: Grant
    Filed: December 17, 1984
    Date of Patent: December 9, 1986
    Inventor: Marshall Daly