Patents by Inventor David Peter Rule

David Peter Rule 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).

  • Extrusion die assembly
    Patent number: 6409491
    Abstract: Disclosed is an improved extrusion die assembly for controlling the flow of polymer in a melt extrusion process. The die assembly is useful for extruding low molecular weight polymer melts.
    Type: Grant
    Filed: February 2, 2001
    Date of Patent: June 25, 2002
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Kenneth Wayne Leffew, David Peter Rule