Patents by Inventor David K. Wohlsdorf

David K. Wohlsdorf 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: 6336325
    Abstract: A hydrostatic loop dump valve for reducing the starting torque required for a hydrostatic unit includes a normally biased open dump valve connecting one or more of the system pressure lines to the reservoir. The dump valve(s) will automatically open and oil will drain out by gravity when the engine is not running. When the engine turns the hydrostatic unit at sufficient speeds to generate significant charge pressure, the dump valves will close and the unit will operate as normal. Thus, the input torque required to start the engine and the hydrostatic unit is minimized without damaging the hydrostatic unit.
    Type: Grant
    Filed: December 7, 1999
    Date of Patent: January 8, 2002
    Assignee: Sauer-Danfoss Inc.
    Inventors: Steven H. Gluck, David K. Wohlsdorf