Patents Assigned to Herrn Georg Pletzer
  • Patent number: 7490421
    Abstract: A method for producing ground surfaces with a hydraulic excavator including a shovel applicable to the surface of the ground, and a lifting cylinder for lifting and lowering the excavator equipment. The lifting cylinder of the excavator equipment is actively connected with at least one work pump via a control device actuated by the operator; and whereby the lifting cylinder is lifted, lowered or blocked depending on the switching position of the control device. For compensating the weight of the excavator equipment and for adjusting an approximately constant pressure of application of the shovel to the surface of the ground as the excavator equipment is moving and working, the lifting side of the lifting cylinder, upon actuation of an actuating element, is automatically acted upon by an adjustable compensation pressure by supplying or evacuating a hydraulic medium.
    Type: Grant
    Filed: July 13, 2000
    Date of Patent: February 17, 2009
    Assignee: Herrn Georg Pletzer
    Inventors: Georg Pletzer, Joachim Waegner, Heinrich Lackenberg