Patents by Inventor Johan A. Sparenberg

Johan A. Sparenberg 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: 5312228
    Abstract: Ship's propeller having a propeller blade having a leading edge and a trailing edge and a free end, and end plates at the free end extending transversely of the blade on both sides of the blade. The line of attachment to the blade of each of the end plates has a chord length less than the chord length of the blade end and the lines of attachment of the end plates overlap each other partly, one end plate extending to the blade leading edge and the other end plate extending to the blade trailing edge. The end plates have airfoil configuration and have leading edges that extend outwardly and rearwardly of the blade with respect to the direction of movement of the blade.
    Type: Grant
    Filed: February 26, 1992
    Date of Patent: May 17, 1994
    Assignee: Stichting Voor De Technische Wetenschappen
    Inventors: Karel De Jong, Jacob De Vries, Johan A. Sparenberg