A device for maintaining a hydraulic supply of a utility vehicle includes a hydraulic pump, which is adjustable in terms of its delivery volume via a pressure control inlet, for feeding hydraulic fluid to a hydraulic circuit, a pressure accumulator that can be charged from the hydraulic circuit via a check valve, a pressure connection between the hydraulic circuit and the pressure control inlet of the hydraulic pump being producible via a sensor line by means of a charging valve, and a supply connection between the pressure accumulator and the hydraulic circuit being producible by means of a discharging valve, by virtue of the check valve being bypassed.

The invention relates to a pressure-limiting device designed to be installed in a system comprising a first line (11) and a second line (12) that can comprise pressurised oil, as well as comprising a discharge and/or booster line (10). The device also comprises a pressure selector (130, 150) in the form of a cage defining two seats (132, 134) and two pressure relief valves (160, 180). The limiting device is characterised in that it further comprises at least one means (170, 172; 190, 192) for regulating a pressure relief valve, disposed on the outside of an axial end of the pressure selector (150), in the form of a cage that allows the loading of the associated pressure relief valve to be regulated.

A hydraulic drive for executing a linear movement includes a motor, a pump, a lifting cylinder having the one linearly movable piston and a cylinder housing with at least one first connection and at least one second connection, a spring arranged such that the piston can be extended or retracted when the spring is in the relaxed state, and at least one first valve with which the first connection and the second connection of the cylinder housing can be fluidly connected. At least one second valve connected in parallel with the first valve is further provided, wherein the first valve has a maximum volumetric throughflow which is greater than the maximum volumetric through-flow of the second valve.

An apparatus and a system directed to an improved hydraulic circuit for use on implements powered by separate motorized vehicle such as a tractor. The apparatus and system include an implement, such as a bale processing or stacking device, configured with wheels to be a towed vehicle, with the towed vehicle configured to be conveyed by a tow vehicle. Additionally, a hydraulic pump on the tow vehicle is coupled to one or more accumulators on the towed device to provide hydraulic power at varying rates as needed by one or more mechanical operations of the implement vehicle. A hydraulic circuit including check and block valves in concert with a pressure switch on the implement device obtains hydraulic power from the tow vehicle from a hydraulic pump located on the tow vehicle via one or more hydraulic transfer lines from the tow vehicle to the implement.

A valve section includes a pressure channel, a load pressure signaling channel, a compound load pressure channel, a spool valve, a pressure compensator, a first and a second hydraulic connection and a first line connecting the pressure channel to the spool valve. The pressure compensator is disposed in the first line. A first pressure signal via a first pilot control line and a third pressure signal are applied to the pressure compensator on the closing side. A second pressure signal via a second pilot control line and a fourth pressure signal are applied to the pressure compensator on the opening side. A fifth pilot control line branches off between the pressure compensator and the spool valve and is connected to the second pilot control line. A first hydraulic resistor is disposed in the fifth pilot control line and a second hydraulic resistor is disposed in the second pilot control line.