Patents by Inventor Piera G. Kelley

Piera G. Kelley 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: 5133005
    Abstract: A line powered telephoe is disclosed in which the telephone is not powered from a separate external source. The improved pay telephone is powered solely by loop current available on the telephone line from the central office. A rechargeable battery is provided to store excess loop current to enable operation of the pay telephone when not off-hook to the central office. Power consumption by components of the telephone is minimized by shutting down unnecessary functions on a selective basis to ensure that sufficient excess loop current is available to recharge the battery. In addition, an improved switched-capacitor circuit is disclosed to enable storage of electricity at a voltage potential higher than the off-hook line voltage to enable firing of standard high voltage relays for coin collection and coin return.
    Type: Grant
    Filed: February 15, 1991
    Date of Patent: July 21, 1992
    Assignee: Elcotel, Inc.
    Inventors: Eugene D. Kelley, Charles E. Murphy, Piera G. Kelley, Donald J. Munn