A hydraulic system for a working vehicle includes a first hydraulic pump to deliver pilot fluid to a control valve for a hydraulic actuator whose highest load pressure acts on a first fluid passage, and a second hydraulic pump to deliver hydraulic fluid whose pressure acts on a second fluid passage. A hydraulic controller is operable to control a load-sensing (LS) differential pressure between the highest load pressure and a delivery pressure of the hydraulic fluid from the second hydraulic pump. A third fluid passage to which the second hydraulic pump delivers the hydraulic fluid branches to a fourth fluid passage for flow of the pilot fluid. A solenoid valve is operable to change a pilot pressure of the pilot fluid for the hydraulic controller, and a controller is configured or programmed to control the solenoid valve to adjust the pilot pressure to change the LS differential pressure.

A refuse vehicle includes a chassis, an energy storage device, a vehicle body, an electric power take-off system, and a hydraulic component. The energy storage device is supported by the chassis and is configured to provide electrical power to a prime mover. Activation of the prime mover selectively drives the refuse vehicle. The vehicle body is supported by the chassis, and includes an on-board receptacle for storing refuse therein. The electric power take-off system is positioned on the vehicle body, and includes an electric motor configured to drive a hydraulic pump to convert electrical power received from the energy storage device into hydraulic power. An amount of electrical power at least one of received by and provided to the electric motor is limited by a controller to control an output characteristic of the hydraulic pump. The hydraulic component is in fluid communication with the hydraulic pump and configured to operate using hydraulic power from the electric power take-off system.

A work vehicle includes computing system is configured to receive a first and seconds inputs associated with controlling an operation of first and second hydraulic loads. Furthermore, the computing system is configured to control the operation of the first or second flow control valve corresponding to the one of the first or second hydraulic loads associated with the greater hydraulic fluid pressure based on the corresponding received first or second input. Additionally, the computing system is configured to determine the first or second pressure of the hydraulic fluid being supplied to another of the first or second hydraulic loads. Moreover, the computing system is configured to control the first or second flow control valve corresponding to the other of the first or second hydraulic loads based on the corresponding received first or second input and the determined first or second pressure.

The present invention provides a construction machine equipped with a pressure accumulation device that accumulates return oil from an actuator, and that can implement both improvement in fuel efficiency with enhancement in workability. To achieve the foregoing, a controller sets an actuator upper limit output power that is an upper limit for an output power of the actuator according to a work mode selected by a work mode selection device, and controls a first control valve and a second control valve such that a sum of an output power of a hydraulic pump and an output power of the pressure accumulation device does not exceed the actuator upper limit output power.

A work vehicle a computing system configured to receive first and second input associated with controlling the operation of the first and second hydraulic load, respectively. Furthermore, the computing system is configured to control the operation of a first or second flow control valve corresponding to the one of the first or second hydraulic loads associated with the greater hydraulic fluid pressure such that the corresponding adjustable orifice is at a maximum flow position. Additionally, the computing system is configured to determine the first and second pressures of the hydraulic fluid being supplied to the first or second hydraulic loads. Moreover, the computing system is configured to control the operation of the first or second flow control valve corresponding to another of the first or second hydraulic loads based on the corresponding received first or second input and the determined first and second pressures.

The present disclosure relates to a hydraulic-electric coupling driven multi-actuator system and control method, and belongs to technical fields of hydraulic transmission and electro-mechanical transmission. The hydraulic-electric coupling driven multi-actuator system comprises one or more hydraulic-electric hybrid driven actuators, first inverters, control valves, centralized hydraulic units and control units, wherein the number of the first inverters and the number of the control valves are the same as that of the hydraulic-electric hybrid driven actuators; each hydraulic-electric hybrid driven actuator is correspondingly connected with one first inverter and one control valve; the centralized hydraulic units are connected with the control valves and configured to supply oil for the hydraulic-electric hybrid driven actuators and to perform power compensation; and the control units are respectively connected with the hydraulic-electric hybrid driven actuators, and each control unit is configured to control output torque of a first motor of the corresponding hydraulic-electric hybrid driven actuator based on pressure information of the hydraulic-electric hybrid driven actuator, such that pressure of driving cavities of the hydraulic-electric hybrid driven actuators is equal, which greatly reduces throttling loss caused by the load differences of the actuators.

Provided is a hydraulic machine. A pump pressurizes fluid using power provided by a power source. An actuator works using the pressurized fluid from the pump. A recovery part recovers energy from fluid discharged from the actuator. A first operator input device receives a desired input from an operator to select an eco-mode or a boost mode. The recovery part includes an accumulator storing hydraulic energy by receiving the fluid discharged from the actuator and an assist unit assisting the power source using the hydraulic energy stored in the accumulator. The controller controls the pump such that output power of the pump does not exceed Plmax when the eco-mode is selected or the assist unit does not assist the power source and that the output power does not exceed P2max when the boost mode is selected and the assist unit assists the power source, where Plmax < P2max.

A method for preventing prime mover stall for a work machine including a hydraulic system having a plurality of control valves served by a hydraulic pump. The method can include determining an actual required flow rate value for the plurality control valves and a total maximum flow rate to the plurality of control valves that will enable the prime mover to operate without stalling. The method can also include operating the plurality of control valves such that the combined total flow of the plurality control valves is at or below the total maximum flow rate such that the pump operates at a condition below which prime mover stall will occur. The method can also include setting a flow sharing allocated specific criteria in which the flow reduction takes place during a flow saturation condition for each of the plurality of control valves such that the total sum of the flow rates (calculated based on the criteria) is equal to or less than the total maximum flow rate.

A prime mover and hydraulic actuators, a hydraulic machine having a rotatable shaft engaged with the prime mover and having a plurality of working chambers, a hydraulic circuit extending between a group of working chambers of the hydraulic machine and the hydraulic actuators, each working chamber of the hydraulic machine having a low-pressure and a high-pressure valve regulating the flow of hydraulic fluid between the working chamber and a corresponding low-pressure manifold and a high-pressure manifold. The hydraulic machine controlling the low-pressure valves of the group of working chambers to select the net displacement of hydraulic fluid by each working chamber on each cycle of working chamber volume, and thereby the net displacement of hydraulic fluid by the group of working chambers, responsive to a demand signal, the apparatus further having a controller calculating the demand signal responsive to a measured property of the hydraulic circuit or an actuator.

A prime mover and a plurality of hydraulic actuators, a hydraulic machine having a rotatable shaft in driven engagement with the prime mover and comprising a plurality of working chambers, a hydraulic circuit extending between a group of one or more working chambers of the hydraulic machine and one or more of the hydraulic actuators, each working chamber of the hydraulic machine comprising a low-pressure valve which regulates the flow of hydraulic fluid between the working chamber and a low-pressure manifold and a high-pressure valve which regulates the flow of hydraulic fluid between the working chamber and a high-pressure manifold. The hydraulic machine being configured to actively control at least the low-pressure valves of the group of one or more working chambers to select the net displacement of hydraulic fluid by each working chamber on each cycle of working chamber volume, and thereby the net displacement of hydraulic fluid by the group of one or more working chambers, responsive to a demand signal, wherein the apparatus further comprises a controller configured to calculate the demand signal in response to a measured property of the hydraulic circuit or one or more actuators.