Patents by Inventor Friedrich-Wilhelm Hoefer

Friedrich-Wilhelm Hoefer 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).

  • Valve arrangement for controlling the flow of hydraulic fluid to and from a user
    Patent number: 4176685
    Abstract: An arrangement for controlling the flow of a hydraulic fluid between a pump, a user and a fluid reservoir includes a main control slide, an auxiliary control slide accommodated in a compartment provided in one end of the main control slide, a flow-regulating valve arranged in parallel to the main control slide between the pump and the fluid reservoir and a holding valve arranged in a pressure conduit section between the main control slide and the user. The main control slide is shiftably received in a bore which has a plurality of annular chambers arranged therealong. The main control slide has a plurality of lands separated by respective recesses, the lands, depending on the position of the main control slide, establishing or interrupting the communication between the respective chambers.
    Type: Grant
    Filed: February 9, 1978
    Date of Patent: December 4, 1979
    Assignee: Robert Bosch GmbH
    Inventors: Friedrich-Wilhelm Hoefer, Walter Gerschwitz, Guenther Schwerin