Robert Boschgmbh

Friedrich-Wilhelm Hoefer

Walter Gerschwitz

Guenther Schwerin

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. The chambers include a switching chamber which communicates with the flow-regulating valve, an input chamber which communicates with the pump, and a control chamber which is arranged between the switching chamber and the input chamber and communicating with the user through the pressure conduit section. The main control slide has an adjustable throttle which influences the flow of the hydraulic fluid between the input chamber and the control chamber. The main control slide is shiftable between an energizing and a deenergizing position through a neutral position and has a first land which interrupts the communication between the switching and control chambers in the energizing position, and a second land which interrupts such communication in the de-energizing position of the main control slide. The first land is arranged at a region of the main control slide which bounds the compartment accommodating the auxiliary control slide.

Growing community of inventors

Ditzingen, Germany

Friedrich-Wilhelm Hoefer