Hydraulic directional control valve for load-independent control of a hydraulic consumer, especially of a mobile machine

摘要

The invention is based on a hydraulic directional valve which is used for load-independent control of a hydraulic consumer, in particular of a mobile machine, with regard to direction and speed. Hydraulic directional control valves of this type are known, the control slide of which can move axially in a slide bore of a valve housing can assume a total of four positions different from the connection of the connections. In a blocking function position, the consumer connections of the directional valve are blocked against the inlet connection and against the outlet connection. In a floating function position, the inlet connection is shut off, while the two consumer connections are fluidly connected to the inlet connection. In two directional function positions of the control slide, one consumer connection is fluidly connected to the inlet connection and the other consumer connection is fluidly connected to the outlet connection. In the known hydraulic directional valves, if one assumes that the control spool is in a rest position, the floating function position takes place in a directional function position of the control spool. DOLLAR A This is disadvantageous in certain applications since, in order to reach the swimming function position, a directional function position has to be crossed and uncontrolled movements of a hydraulic consumer can occur. This is prevented if, according to the invention, the hydraulic directional valve is designed ...