Patents by Inventor Robert Biornstad

Robert Biornstad 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 for minimizing fiber distortion during fabrication of one-piece composite barrel section
    Patent number: 8691037
    Abstract: A method for fabricating a one-piece composite fuselage section that minimizes out-of-plane fiber distortion. This is accomplished by fabricating a mandrel having a coefficient of thermal expansion in the hoopwise direction that is sufficiently greater than that of the laid-up composite ply assembly. As a result of this differential in the coefficients of thermal expansion in the hoopwise direction, the laid-up composite ply assembly is stretched circumferentially as the mandrel expands radially during cure, thereby eliminating or reducing out-of-plane fiber distortion. At the same time, the mandrel and part being fabricated should have substantially the same coefficient of thermal expansion in the lengthwise direction. As the outer surface of the mandrel increases in circumference, the circumferentially oriented reinforcing fibers of the inner plies are stretched, while the circumferentially oriented reinforcing fibers of the outer plies do not reduce in circumference and thus do not form waves or wrinkles.
    Type: Grant
    Filed: December 14, 2006
    Date of Patent: April 8, 2014
    Assignee: The Boeing Company
    Inventors: William H. Ingram, Jr., Kenneth M. Dull, Robert Biornstad
  • Method for minimizing fiber distortion during fabrication of one-piece composite barrel section
    Publication number: 20100024964
    Abstract: A method for fabricating a one-piece composite fuselage section that minimizes out-of-plane fiber distortion. This is accomplished by fabricating a mandrel having a coefficient of thermal expansion in the hoopwise direction that is sufficiently greater than that of the laid-up composite ply assembly. As a result of this differential in the coefficients of thermal expansion in the hoopwise direction, the laid-up composite ply assembly is stretched circumferentially as the mandrel expands radially during cure, thereby eliminating or reducing out-of-plane fiber distortion. At the same time, the mandrel and part being fabricated should have substantially the same coefficient of thermal expansion in the lengthwise direction. As the outer surface of the mandrel increases in circumference, the circumferentially oriented reinforcing fibers of the inner plies are stretched, while the circumferentially oriented reinforcing fibers of the outer plies do not reduce in circumference and thus do not form waves or wrinkles.
    Type: Application
    Filed: December 14, 2006
    Publication date: February 4, 2010
    Inventors: William H. Ingram, JR., Kenneth M. Dull, Robert Biornstad