Patents by Inventor Robert Carter Johnstone

Robert Carter Johnstone 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).

  • Method and spinning apparatus having a multiple-temperature control arrangement therein
    Patent number: 5866050
    Abstract: A method and apparatus for spinning filaments of a polymeric material includes a first temperature control arrangement for heating a spin pack to a first predetermined reference temperature greater than the predetermined polymer inlet temperature such that the temperature across a polymer filter holder and the spinneret plate in the spin pack is substantially uniform, whereby the temperature of the filaments emanating from the spinneret plate is substantially uniform. A plate assembly having at least one polymer flow passage therein is disposed between the outlet of the pump and the inlet of the spin pack. A second temperature control arrangement for independently controlling the temperature of the plate assembly to a second predetermined reference temperature is provided.
    Type: Grant
    Filed: February 6, 1997
    Date of Patent: February 2, 1999
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Leland Luper Krauss, Duncan Douglas McCabe, Robert Carter Johnstone, Robert Carl Boger