Patents by Inventor Douglas Kalvelage

Douglas Kalvelage 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).

  • Variable resistance tracton sled for skaters
    Publication number: 20050023779
    Abstract: A sled type device consisting of a rigid platform 16 supported by a multitude of flexible filaments 18A, 18B, 18C and 18D. It is pulled by a skater for strengthening purposes. The filaments are attached to the platform in a way that causes downward pressure to vary the number of filaments touching the skating surface. The skater is connected to the sled by a rope and pulley harness that effectively eliminates sideways forces from being transmitted by the skater to the sled.
    Type: Application
    Filed: June 24, 2004
    Publication date: February 3, 2005
    Inventor: Douglas Kalvelage