An apparatus includes a housing, a piston, an input cavity, a first actuating shaft, a first output cavity, and a second output cavity. The housing comprise an input port, a first output port, a second output port, a first end, a second end, a first wide wall having a first internal surface, and a chamber at least partially defined by the first end and the first internal surface. The piston is able to actuate along the first internal surface of the first side wall. The input cavity is in fluid communication with the input port. The first output cavity is in fluid communication with the first output port. The second output cavity is in fluid communication with the second output port. The first actuating shaft is fixed to the piston and helps fluidly isolate the first output port from the second output port.

A fluid system includes a variable-speed and/or a variable-torque pump to pump a fluid, at least one proportional control valve assembly, an actuator that is operated by the fluid to control a load, and a controller that establishes a speed and/or torque of the pump and a position of the at least one proportional control valve assembly. The pump includes at least one fluid driver that provides fluid to the actuator, which can be, e.g., a fluid-actuated cylinder, a fluid-driven motor or another type of fluid-driven actuator that controls a load. Each fluid driver includes a prime mover and a fluid displacement assembly. The fluid displacement assembly can be driven by the prime mover such that fluid is transferred from the inlet port to the outlet port of the pump.

A safe hydraulic drive system and process, comprising at least one first cylinder chamber and a second, separate cylinder chamber which are connected to one another via a connecting line to form a fluid-filled hydraulic circuit, and a hydraulic drive for conveying the fluid from one cylinder chamber, via the connecting line, into the other cylinder chamber in which the connecting line is arranged. The connecting line has at least one parallel system, between the hydraulic drive and one of the two cylinder chambers, including at least one first sub-connection with at least one first stop valve and a second sub-connection with a baffle arranged therein. The connecting line, excluding the second sub-connection, has a first flow resistance and the second sub-connection has a second flow resistance due to the baffle arranged therein, which is greater than the first flow resistance for the fluid, wherein the drive system is provided with at least one open first stop valve in normal mode and with a closed first stop valve in safe mode for conveying the fluid, and a suitably high second flow resistance has been selected so that a maximum permissible speed for a piston rod is not exceeded in safe mode, even when an external force acts on the drive system in the direction of movement of the piston rod.

An electropneumatic positioner for a pneumatic actuator to operate a control device of a processing plant can include two modular pneumatic slots and a pneumatic control output. The two modular pneumatic slots can engage with a respective modular pneumatic component. The two pneumatic slots and the pneumatic components can be modularly matched to one another such that their respective pneumatic interfaces merge into one another when a pneumatic slot is engaged. The pneumatic control output can output a pneumatic control pressure signal to the pneumatic actuator. The two modular pneumatic slots and the pneumatic control output can form a pneumatic series connection.

A hydraulic drive system for operating a hydraulic cylinder in first and second movement profiles. A hydraulic drive unit includes first and second hydraulic machines, each with first and second connections. In the first movement profile, a first cylinder chamber of the hydraulic cylinder is fluidly connected to a first fluid reservoir and a second cylinder chamber is fluidly connected to the second connection of the second hydraulic machine. In the second movement profile, the first connection of the first hydraulic machine is connected to the second connection of the second hydraulic machine.

A method for storing and reusing hydraulic energy in a machine is disclosed. The method includes transferring the hydraulic energy from an actuator to an upstream side of a motor pump via a first valve, during a normal mode. The method includes directing excess hydraulic energy from a downstream side of the motor pump to an accumulator by opening an accumulator valve and closing a bypass valve, during an energy saving mode. The method includes retrieving stored hydraulic energy from the accumulator to the upstream side of the motor pump by opening the accumulator valve, during an energy discharging mode.

A load-controlled hydraulic supply for an attachment attached to an agricultural tractor includes a hydraulic high-pressure source providing a volume flow in a supply line, a pressure-compensated control valve including an actuation device for adjusting the volume flow in the supply line, a return line leading to a hydraulic reservoir, and a load-indicating line. The volume flow is adjusted based on pressure feedback prevailing at the load-indicating line.

A linear actuator system includes a linear actuator and at least one integrated pump assembly connected to the linear actuator to provide fluid to operate the linear actuator. The integrated pump assembly includes a pump with at least one fluid driver comprising a prime mover and a fluid displacement assembly to be driven by the prime mover such that fluid is transferred from a first port of the pump to a second port of the pump. The pump assembly also includes two valve assembles to isolate the pump from the system. The linear actuator system also includes a controller that establishes at least one of a speed and a torque of the at least one prime mover to exclusively adjust at least one of a flow and a pressure in the linear actuator system to an operational set point.

A linear actuator system includes a linear actuator and an integrated pump assembly connected to the linear actuator to provide fluid to operate the linear actuator. The integrated pump assembly includes a pump with two fluid drivers, each fluid driver comprising a prime mover and a fluid displacement assembly to be driven by the prime mover such that fluid is transferred from a first port of the pump to a second port of the pump. The pump assembly also includes two valve assembles to isolate the pump from the system. The linear actuator system also includes a controller that establishes the pump in a normal mode of operation in which the prime movers are independently driven and switches to a fail-safe mode of operation in which only one prime mover is operated.

A hydraulic drive device for cargo handling vehicle has: a tank; a pump for drawing in a hydraulic oil from the tank and supplying the hydraulic oil to hydraulic cylinders; an electric motor for driving the pump; a solenoid-controlled proportional valve disposed between an inlet port of the pump and a bottom chamber of an up-and-down hydraulic cylinder and configured to open with a valve travel depending upon a control input of a descent control of an up-and-down control member; a pressure compensation valve disposed between a branch portion located between the pump and the solenoid-controlled proportional valve and the tank and configured to open with a valve travel depending upon a pressure difference between pressures upstream and downstream of the solenoid-controlled proportional valve; and a valve disposed between the pressure compensation valve and the tank and configured to be switched between an open position and a close position.