Patents by Inventor Walter R. Andrews, Jr.

Walter R. Andrews, Jr. 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).

  • Process of making high strength, low shrinkage polyamide yarn
    Patent number: 5240667
    Abstract: An improved process for making high tenacity polyamide yarn of the type including the coupled steps of spinning, drawing the yarn at least about 5.OX in stages, the final draw stage employing final stage draw rolls which are heated to above about 200.degree. C., relaxing the yarn by advancing the yarn onto at least one tension letdown roll, and winding up the yarn. The improved process includes heating the yarn tension letdown roll to above about 200.degree. C., rotating the tension letdown roll at a peripheral speed which is at least about 11% less than the peripheral speed of the final stage draw rolls, and contacting the yarn between the final stage draw rolls and the tension letdown roll with tension control means for increasing the tension on the yarn advancing onto the tension letdown roll.
    Type: Grant
    Filed: November 13, 1991
    Date of Patent: August 31, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Walter R. Andrews, Jr., Marion R. De Witt, Jr.
  • Dip penetration regulators for tire yarns
    Patent number: 5096778
    Abstract: A polyamide yarn having on the surface of the polyamide yarn a hydrophobic organic ester dip penetration regulator having a melting point greater than 27.degree. C. and convertible by conventional means into a tire cord having low stiffness and high air permeability and a process for making polymeric tire yarns is disclosed.
    Type: Grant
    Filed: November 9, 1989
    Date of Patent: March 17, 1992
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Walter R. Andrews, Jr., Fleming H. Day
  • Process for making a tire cord using yarns containing a dip penetration regulator
    Patent number: 4900496
    Abstract: A polyamide yarn having on the surface of the polyamide yarn a hydrophobic organic ester dip penetration regulator having a melting point greater than 27.degree. C. and convertible by conventional means into a tire cord having low stiffness and high air permeability and a process for making polymeric tire yarns is disclosed.
    Type: Grant
    Filed: July 22, 1988
    Date of Patent: February 13, 1990
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Walter R. Andrews, Jr., Fleming H. Day