Patents by Inventor Hendrik Johannes Zwaan

Hendrik Johannes Zwaan 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).

  • Jet propulsion pump
    Patent number: 6533622
    Abstract: A jet propulsion pump (10) for use with watercraft includes a propeller (40) mounted on a shaft (42) for axial rotation, and a pump chamber (20) having a cylindrical inlet (30) and a downwardly inclined outlet (50) connected to an aperture (29) in the pump chamber (20). The propeller (40) is positioned within the cylindrical inlet (30). An outer wall portion (24) of the pump chamber (20) is outwardly spiralling from the cylindrical inlet (30) to assist flow of fluid entering the pump chamber (20) through the cylindrical inlet (30) and expelling from the pump chamber (20) at the downwardly inclined outlet (50).
    Type: Grant
    Filed: July 6, 2001
    Date of Patent: March 18, 2003
    Inventors: Hendrik Johannes Zwaan, Craig Zwaan
  • Paddle
    Publication number: 20010053641
    Abstract: A paddle for use with a kayak, canoe or similar watercraft is provided with a rotatable hand grip in the form of a sleeve, the sleeve being rotatable about a shaft of the paddle The rotatable hand grip is provided with a retaining means to retain the sleeve in a pre-determined location along the length of the shaft.
    Type: Application
    Filed: June 4, 2001
    Publication date: December 20, 2001
    Inventors: Hendrik Johannes Zwaan, Craig Zwaan