Abstract: The invention relates to a hydraulic control device for a priority, first hydraulic consumer and a subordinate, second hydraulic consumer, pressure medium being deliverable to the first or the second consumer via a first or a second metering diaphragm. A pressure scale which allows a constant pressure difference to be adjusted above the first metering diaphragm is mounted upstream from the first metering diaphragm. For this purpose, said pressure scale is provided with a valve piston encompassing a first control edge, by means of which a first flow area between a feeding duct and the first metering diaphragm can be controlled. A second pressure scale which can be impinged upon in the closing direction by control pressure prevailing in a control chamber while being impinged upon in the opening direction by the pressure applied downstream from the second measuring diaphragm is mounted downstream from the second measuring diaphragm.

Abstract: A hydraulic control arrangement is disclosed for the control of a consumer, comprising at least one mechanically operated continuously adjustable distribution valve with a subsequent LUDV pressure compensator down the line. In order to lock the consumer the control arrangement is provided with a spring holding the pressure compensator piston in a closed position. Furthermore, the LS line carrying the highest load pressure of all consumers is connected to a reservoir by means of a flow regulator, wherein the pump control may also be relieved by the flow regulator in the sense of a reduction of the pumped volume. According to the invention, the LUDV pressure compensator is pressure-compensated by means of a nozzle through which a connection between the LS line and a portion of the pressure medium flow path downstream of the pump and upstream of the outlet of the pressure compensator is generated. Said nozzle is preferably integrated in the pressure compensator piston.

Abstract: What is disclosed is a hydraulic control arrangement for a mobile equipment, such as for a backhoe loader or a wheel loader, wherein a working tool of the equipment is adapted to be actuated by means of a hydraulic cylinder whose pressure chambers may jointly be connected with a hydraulic accumulator 14 for attenuating pitching oscillations of the working tool.

Abstract: What is disclosed is a control arrangement for an equipment, in particular a wheel loader or a backhoe loader having a shovel mounted articulatedly at a boom, wherein the control arrangement enables a control of the shovel by means of a control pressure of a boom control unit, so that the latter may be taken into a target position during lowering of the boom or while the boom is taken into a floating condition.

Abstract: The invention relates to a hydraulic control system for providing at least one hydraulic consumer with a pressure medium. Said system comprises an LS pump system and a metering port for adjusting the pressure medium volume flow rate towards the consumer. The LS line is connected to a pressure medium sink via a current regulator. The invention is characterized in that the current regulator can be adjusted depending on the pump rate in order to modify the pressure drop at the metering port.

Abstract: On a work appliance, an extension arm is held rotatably, and a scoop is held rotatably on the extension arm. The actuation of the extension arm and of the scoop takes place in each case by means of a hydraulic cylinder. Each cylinder is assigned a valve which controls the flow of pressure medium from a pump to the cylinder and from the latter to the tank. A rotational movement of the extension arm entails a change in the angular position of the top edge of the scoop, this change having an adverse effect during the raising of the extension arm, particularly when the scoop is full.

Abstract: What is disclosed is a hydraulic control system for controlling a hydraulic consumer actuating a working tool of a mobile equipment that is provided with oscillation damping means for attenuating oscillations during braking of the working tool. In accordance with the invention, the oscillation damping means comprise two pilot-controlled shut-off valves arranged in opposite directions, that are positioned in a connecting line between a pressure medium supply and a pressure medium drain. The shut-off valves are subjected to the pressure in the drain and in the delivery, respectively, in the opening direction, and also to this pressure and to the force of a spring in the closing direction. Following a predetermined initial stroke of a regulator of the control system, the pressure acting on the drain-side shut-off valve in the closing direction may be reduced, so that the latter is opened by the pressure in the drain, and the connecting line between delivery and return is opened.

Abstract: What is disclosed is a hydraulic control system for a mobile equipment, in particular for a wheel or backhoe loader, wherein a shovel is linked to a boom. The angular position of the shovel may be kept constant through the intermediary of an orientation control device during a pivoting movement of the boom relative to the axles of the equipment. In accordance with the invention, the orientation control device is realized such that in the event of a change of a pre-set angular position, a control signal is generated through a pilot control device, whereby a shovel control unit may be controlled in such a manner that the shovel is again returned into its predetermined angular position.

Abstract: A hydraulic control arrangement is disclosed for the load pressure independent control of a consumer, comprising a distribution valve forming an inlet metering orifice, a corresponding individual pressure compensator, a stop valve provided for each consumer connection which may be released by means of a pilot valve and an anti-cavitation valve by means of which pressure medium can be drawn from a reservoir to avoid cavitation. According to the invention, the distribution valve and the stop valves are arranged along two parallel axes, while the axes of the two pilot valves are arranged perpendicularly to these two axes. The anti-cavitation valves in turn extend perpendicularly to the axes of the distribution valves, the stop valves and the anti-cavitation valves.

Abstract: Hydraulic control arrangement for a mobile equipment What is disclosed is a control arrangement for an equipment, in particular a wheel loader or a backhoe loader having a shovel mounted articulatedly at a boom, wherein the control arrangement enables a control of the shovel by means of a control pressure of a boom control unit, so that the latter may be taken into a target position during lowering of the boom or while the boom is taken into a floating condition.

Abstract: Hydraulic control arrangement for a mobile equipment What is disclosed is a hydraulic control arrangement for a mobile equipment, such as for a backhoe loader or a wheel loader, wherein a working tool of the equipment is adapted to be actuated by means of a hydraulic cylinder whose pressure chambers may jointly be connected with a hydraulic accumulator 14 for attenuating pitching oscillations of the working tool.

Abstract: The invention relates to a power control unit for a hydrostatic piston engine, the volumetric flow of which can be varied by a control unit (5). An operating pressure prevailing in the control unit (5) is controlled by a power regulating valve (9), which is connected to the control unit (5) by a feeder pipe (12). A non-return valve (15) and a throttle point (14) arranged parallel thereto are provided in the feeder pipe (12).

Abstract: A hydraulic control arrangement is disclosed for the control of a consumer, comprising at least one mechanically operated continuously adjustable distribution valve with a subsequent LUDV pressure compensator down the line. In order to lock the consumer the control arrangement is provided with a spring holding the pressure compensator piston in a closed position. Furthermore, the LS line carrying the highest load pressure of all consumers is connected to a reservoir by means of a flow regulator, wherein the pump control may also be relieved by the flow regulator in the sense of a reduction of the pumped volume. According to the invention, the LUDV pressure compensator is pressure-compensated by means of a nozzle through which a connection between the LS line and a portion of the pressure medium flow path downstream of the pump and upstream of the outlet of the pressure compensator is generated. Said nozzle is preferably integrated in the pressure compensator piston.

Abstract: A hydraulic control arrangement is disclosed for the load-independent control of a consumer with a continuously adjustable distribution valve having a pressure compensator down the line. According to the invention, the pressure compensator has a single-sided damping such that the movement in the opening direction is damped and the movement in the closing direction is substantially undamped. Furthermore, a control arrangement is disclosed in which a load-holding function is integrated in the pressure compensator.

Abstract: A valve assembly for load pressure-independent control of consumers is disclosed, which includes a main valve having a directional element and a metering throttle part. The valve assembly includes a shut-off valve for leakage-free shutting off of a work line leading to the consumer. This shut-off valve is designed with a pilot valve whereby a pressure chamber of the shut-off valve acting in the closing direction may be relieved towards a tank or a low-pressure source. The pilot valve is, in accordance with the invention, controlled open by a main slide of the main valve.

Abstract: A hydraulic control arrangement is disclosed for the load pressure independent control of a consumer, comprising a distribution valve forming an inlet metering orifice, a corresponding individual pressure compensator, a stop valve provided for each consumer connection which may be released by means of a pilot valve and an anti-cavitation valve by means of which pressure medium can be drawn from a reservoir to avoid cavitation. According to the invention, the distribution valve and the stop valves are arranged along two parallel axes, while the axes of the two pilot valves are arranged perpendicularly to these two axes. The anti-cavitation valves in turn extend perpendicularly to the axes of the distribution valves, the stop valves and the anti-cavitation valves.

Abstract: What is disclosed is a pilot apparatus whereby at least two mechanically operable control valves and two electrically or electro-hydraulically operable control valves may be driven. The pilot apparatus comprises a pivoted lever having two handles, on each of which a switching element for driving the electrically/electro-hydraulically operable control valves is provided.

Abstract: A valve assembly for load pressure-independent control of consumers is disclosed, which includes a main valve having a directional element and a metering throttle part. The valve assembly includes a shut-off valve for leakage-free shutting off of a work line leading to the consumer. This shut-off valve is designed with a pilot valve whereby a pressure chamber of the shut-off valve acting in the closing direction may be relieved towards a tank or a low-pressure source. The pilot valve is, in accordance with the invention, controlled open by a main slide of the main valve.

Abstract: A hydraulic control arrangement which is provided for the demand-feed-regulated supply of pressure medium to preferably a plurality of hydraulic consumers by proportionally adjustable directional valves. There are hydraulic pumps by which pressure medium can be conveyed in a quantity corresponding to the demand into a common inflow line leading to the directional valves. A first demand-feed regulator is assigned to the first hydraulic pump and a second demand-feed regulator to the second hydraulic pump. The two demand-feed regulators are capable of being acted upon, with the effect of increasing the pressure medium quantity discharged into the inflow line by the corresponding hydraulic pump, by a spring and, on a first active surface, by the pressure in a load-signaling line and, with the effect of reducing the pressure medium quantity discharged into the inflow line by the corresponding hydraulic pump, on a second active surface, by a pump pressure.

Abstract: A hydraulic distributor that has a regulating balance including a housing hollowed in the distributor body and containing coaxially a fixed central core. A tubular plunger is interposed sliding freely, coaxially, between the core and the housing and co-operates with a lateral orifice connected to a working orifice. The core and the plunger define between them an annular chamber. The plunger has a first radial annular surface subjected to the highest charge pressure (LS) and a second annular surface subjected to the pressure of the intake fluid. A central passage in the core constitutes a first orifice emerging at one end of the housing exposed to the highest charge pressure (LS). A second orifice emerges in the annular chamber and a third orifice is located opposite the other end of the housing and remains closed by the plunger as long as the charge pressure of the distributor is below the highest charge pressure (LS).