A hydraulic lifting device for a chassis of a mobile device has a valve block, a pump, a tank, a first cylinder device and a second cylinder device. The first cylinder device and the second cylinder device can be selectively pressurized by the pump or connected to tank via the valve block. The first cylinder device is connected to the pump via at least one primary non-return valve disposed in the valve block. The second cylinder device is connected to the pump via at least one secondary non-return valve disposed in the valve block. The valve block has at least one pressure accumulator downstream of the at least one secondary non-return valve in the flow direction from the pump to the second cylinder device. Furthermore, a chassis with such a lifting device and to a mobile device with a chassis is provided.

A system has a hydraulic circuit configured to control a position of an attachment of the system and a control system configured to perform operations that include receiving an input indicative of a center of gravity of the attachment and controlling a flow rate of fluid directed through the hydraulic circuit based on the center of gravity.

An electric-powered fail-safe actuator for use with a valve, where the actuator stores potential energy for conversion to kinetic energy to close or open the valve to the fail-safe position.

A solenoid driven actuator system includes a first solenoid having at least one pressure input and a pressure outlet downstream from the at least one pressure input. The system includes a second solenoid having at least one pressure input and a pressure outlet downstream from the at least one pressure input. The system includes a pressure-switching valve operatively coupled to the first and second solenoids. The system includes an actuator operatively coupled to the pressure outlet of the second solenoid.

A solenoid driven actuator system includes a first solenoid having at least one pressure input and a pressure outlet downstream from the at least one pressure input. A second solenoid has at least one pressure input and a pressure outlet downstream from the at least one pressure input. A transfer solenoid operatively coupled to the first and second solenoids. An actuator valve operatively coupled to a pressure outlet of the transfer solenoid.

A work vehicle includes a lifting mechanism to control at least one of a height and a posture of a work machine connected to the work vehicle. The lifting mechanism is able to control at least one of the height and the posture by using a hydraulic drive. The work vehicle includes an oil-temperature acquirer to acquire an oil temperature to be used for the hydraulic drive, a maximum oil amount setter to set a maximum oil amount according to the oil temperature acquired by the oil-temperature acquirer, the maximum oil amount being a maximum value of a supply amount of oil used to drive the hydraulic drive, and a hydraulic drive controller to control the hydraulic drive below the maximum oil amount set by the maximum oil amount setter.

An electric-powered fail-safe actuator for use with a valve, where the actuator stores potential energy for conversion to kinetic energy to close or open the valve to the fail-safe position.

Systems, methods and devices are described providing a selective hydraulic or electrically powered prime mover that is a bi-directional power unit system, including movement within a device used to compress and/or expand a fluid and provide fluid movement. The use of a hydraulic power unit is involved and comprises at least a pump or other fluid moving device, a first set of selective control valves delivering pressurized fluid to the device(s), and a second set of selective control valves returning unpressurized fluid from the device(s), a reservoir comprising a compensator tank, a port for operation at ambient pressure, and a pressure measuring device measuring ambient pressure allowing for unbalanced flow to and from the device as well as thermal expansion or compression. The use of a multiport and in some cases a swashplate pump that incorporates the features and functions of several valves for the system is also described.

Valve arrangement for influencing a fluid flow for a fluid consumer, having a first valve group with which a first actuator is associated, having a second valve group with which a second actuator is associated, the first valve group and second valve group being associated in a first functional position as a parallel circuit with a first fluid line in a first functional position and are associated with a second fluid line in a second functional position as a series circuit, the first valve group or second valve group being designed for actuating the respective other actuator in the first functional position and being designed for switching off the respective other actuator in the second functional position.

To generate a setpoint signal to stroke a valve during a partial-stroke test, a first target is determined for the setpoint signal based at least on a travel displacement threshold, the travel displacement threshold corresponding to a desired extent of travel of the valve during the partial-stroke test; the setpoint signal is ramped from an initial value to the first target, during a first time interval; subsequently to the first time interval, the setpoint signal is maintained at the first target during a second time interval; a second target is determined for the setpoint signal based at least on the initial value; and during a third time interval subsequent to the second interval, the setpoint signal is ramped from the first target to the second target in a direction opposite to the ramping of the setpoint signal during the first time interval.