Patents by Inventor David K. Hooper

David K. Hooper 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).

  • Composite railroad tie
    Patent number: 4034913
    Abstract: An improved railroad tie constructed of a metal sheath with angled walls braced longitudinally, vertically, and laterally and reinforced by a filling of concrete, the sheath structure being especially adapted for spring-type rail securing devices bridging the side walls of the shell. Hand-hold recesses are provided at the ends to facilitate manual handling of the ties.
    Type: Grant
    Filed: February 26, 1976
    Date of Patent: July 12, 1977
    Inventor: David K. Hooper