Patents by Inventor Doris Lynn Davis

Doris Lynn Davis 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).

  • Interchange sealing device and method
    Patent number: 5918638
    Abstract: A sealing apparatus for providing a sealing engagement with an internal surface of a pipe in order to plug the pipe. The apparatus has a pair of plate members. A sealing member with a pair of flanges is positioned between the pair of plate members. A rod passes through the two plate members and the sealing member. A coupling assembly is connected to one of the plate members for releasably engaging a plunger. A method for plugging a pipe including the steps of disposing the sealing assembly in a pipe; and moving one of the plate members towards the other plate members such that the pair of flanges move outwardly and towards each other to sealably engage the internal surface of the pipe to plug the same.
    Type: Grant
    Filed: May 2, 1997
    Date of Patent: July 6, 1999
    Inventor: Doris Lynn Davis
  • Sealing unit
    Patent number: D411612
    Type: Grant
    Filed: May 5, 1997
    Date of Patent: June 29, 1999
    Inventor: Doris Lynn Davis