Patents by Inventor Habib G. Rai

Habib G. Rai 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).

  • Patent number: 5462618
    Abstract: A method of forming a pultruded shaped composite material comprising carbon fiber having a diameter not greater than 0.001 inch aligned linearly with a degree of waviness defined by an average amplitude to length (A/L) ratio of less than 0.9 percent in a matrix is formed around the fiber and solidified or cured into a rigid form that will not melt during subsequent processing steps to prevent an increase in waviness during subsequent processing steps. The compressive strength of the composite material approaches the tensile strength of the material. The matrix material consists essentially of a resin present in the range of about 10 to 50 percent by volume of the composite material. The A/L ratio is determined by measuring the distribution of angularity found in the aligned carbon fibers in a selective cross section cut at five degrees to the fiber plane, wherein the standard deviation for a 300 sample angularity measurement is not greater than 0.88 degrees.
    Type: Grant
    Filed: June 2, 1994
    Date of Patent: October 31, 1995
    Assignee: Bell Helicopter Textron Inc.
    Inventors: Charles W. Rogers, David A. Crane, Habib G. Rai
  • Patent number: 5324563
    Abstract: A pultruded shaped composite material of carbon fiber having a diameter not greater than 0.001 inch aligned linearly with a degree of waviness defined by an average amplitude to length (A/L) ratio of less than 0.9 percent, the matrix formed around the fiber and solidified or cured into a rigid form that will not melt during subsequent processing steps to prevent an increase in waviness during subsequent processing steps. The matrix material consists essentially of a resin present in the range of about 10 to 50 percent by volume of the composite material. The A /L ratio is determined by measuring the distribution of angularity found in the aligned carbon fibers in a selective cross section cut at five degrees to the fiber plane, wherein the standard deviation for a 300 sample angularity measurement is not greater than 0.88 degrees.
    Type: Grant
    Filed: March 23, 1993
    Date of Patent: June 28, 1994
    Assignee: Bell Helicopter Textron Inc.
    Inventors: Charles W. Rogers, David A. Crane, Habib G. Rai