Patents by Inventor Marius Constantijn

Marius Constantijn 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).

  • Wheelchair which is provided with a swivel castor
    Patent number: 5984333
    Abstract: A wheelchair with adjustable swivel castors is described. The wheelchair includes a mechanism to limit the swivel range of the castors. The swivel range may be limited manually or automatically as a function of the terrain or the speed of the chair.
    Type: Grant
    Filed: June 19, 1997
    Date of Patent: November 16, 1999
    Assignee: Ligtvoet Products B.V.
    Inventors: Marius Constantijn, Arnoldus V. Vorst