Patents by Inventor Stephan Lawitzki

Stephan Lawitzki 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: 4961476
    Abstract: The arrangement controls a friction element for limiting a rotational speed compensation between the axles of a two-axle or all-wheel-driven vehicle as a function of the difference of the medium wheel speeds of both axles (longitudinal speed difference). This longitudinal speed difference is compared with two driving-speed-dependent tolerance bands, the first tolerance band being determining for positive and the second tolerance band being determining for negative longitudinal speed differences. If the values of the longitudinal speed differences are above the first or below the second tolerance band, the limiting is increased; if the values are within the tolerance bands, the instantaneous limiting is maintained; and if the values are between the tolerance bands, the limiting is reduced. This arrangement may also be expanded to include an adaptation device of the limit criteria with respect to different tread radii of the wheels and a cornering correction device.
    Type: Grant
    Filed: March 30, 1989
    Date of Patent: October 9, 1990
    Assignee: Dr. Ing. h.c.F. Porsche AG
    Inventors: Lothar Witte, Norbert Stelter, Ulrich Appt, Rolf Geiger, Klaus-Gerhard Wolpert, Stephan Lawitzki
  • Patent number: D495981
    Type: Grant
    Filed: December 18, 2002
    Date of Patent: September 14, 2004
    Assignee: Dr. Ing. h.c.F. Porsche Aktiengesellschaft
    Inventors: Winfried Tölle, Ulrich Sauter, Stephan Lawitzki