Patents by Inventor Frederic Hagen

Frederic Hagen 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).

  • Water sports wheel
    Patent number: 3934291
    Abstract: A unitary hollow paddle wheel of a size to receive a person in upright position and composed of two circular pneumatic tubes connected in spaced relation by transverse members that also support a tread which is operated by the person within the wheel to propel the same in a forward or backward direction and through which the person may observe his progress.
    Type: Grant
    Filed: August 23, 1974
    Date of Patent: January 27, 1976
    Assignee: Douglas Leigh Research and Development Corporation
    Inventor: Frederic Hagen