A control system includes a cylinder pressure data acquisition unit that acquires cylinder pressure data indicating a pressure of operating oil of a hydraulic cylinder; an operation amount data acquisition unit that acquires operation amount data of an operating device; a pump flow rate calculation unit that calculates a first pump flow rate indicating a flow rate of the operating oil discharged from a first hydraulic pump and a second pump flow rate indicating a flow rate of the operating oil discharged from a second hydraulic pump in a splitting state in which a passage is closed based on the cylinder pressure data and the operation amount data; and a pump control unit that controls the first hydraulic pump and the second hydraulic pump based on the first pump flow rate and the second pump flow rate.

A operator supporting electrohydraulic drive and control system based on, position sensors (8) (9), a electronic control unite ECU (2), a recovery, storing and re-use system for energy, and with actuator (3) (4) and the drive control valve (6) (7) bolted together in one (3+6) (4+7) unite and with the valve (6) (7) independently of the ECU (2) is controlling effective use of pump capacity and recovery of energy and with control of speed for low speeds, or prevented speed by valves (6) (7) or pump (10) (10a) (11) (11a) displacement and for higher speed with control of deplacement of pumps and motors and with valves (6) (7) at the same time controlled to be fully open.

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 refuse vehicle includes a chassis and a vehicle body. A variable displacement pump is positioned within the vehicle body and is configured to pump hydraulic fluid from a hydraulic fluid reservoir into a high pressure line of a hydraulic circuit. A lifting system on the vehicle includes at least one actuator in fluid communication with the variable displacement pump, which delivers pressurized hydraulic fluid from the hydraulic fluid reservoir to the actuator through the high pressure line to adjust a position of the actuator. A valve is positioned downstream of the variable displacement pump. In a first valve position, the valve restricts flow outward from the high pressure line. In a second valve position, the valve directs fluid from the high pressure line into a lower pressure line to reduce a hydraulic pressure within the high pressure line and adjust an output parameter of the variable displacement pump.

In general, certain embodiments of the present disclosure provide an electro-hydrostatic actuator comprising a piston assembly and a hydraulic cylinder. The piston assembly, having a piston head and a piston rod extending from the piston head, is located and movable within the hydraulic cylinder. The hydraulic cylinder includes a hydraulic fluid chamber region including a piston side chamber and a rod side chamber, a reservoir for storing hydraulic fluid located within the hydraulic cylinder which is in fluid communication with the hydraulic fluid chamber region. The electro-hydrostatic actuator includes a hydraulic pump system for moving hydraulic fluid in the reservoir and the hydraulic fluid chamber region, the hydraulic pump system in fluid communication with a flow control network in a hydraulic cylinder boss for controlling a direction and flow magnitude of hydraulic fluid within the hydraulic fluid chamber region, and an electric motor for driving the hydraulic pump system.

A hydraulic control system for a machine is provided. The hydraulic control system includes a fluid reservoir and a pump motor. The pump motor is fluidly coupled to the fluid reservoir. The pump motor is configured to provide pressurized fluid and to receive fluid to provide a power output to the shaft. The hydraulic control system further includes an actuator and an accumulator fluidly coupled to the pump motor and the actuator. The hydraulic control system further includes an accumulator valve and a controller. The accumulator valve is fluidly coupled between the accumulator and the pump motor. The controller is in communication with the pump motor and the accumulator valve. The controller is configured to detect an operator command to operate the power source; determine pressure at the accumulator; and selectively move the accumulator valve to fluidly connect the accumulator with the pump motor.

A valve block arrangement configured as a closed center system includes at least one main spool for controlling a hydraulic consumer. The main spool is configured to open and close at least one pressure medium connection between a hydraulic pump and the consumer in controlled, continuous fashion and, in at least one embodiment, is electrically activated. A bypass flow path with a cut valve branches off between the adjustable, hydraulic pump and the main spool. The cut valve is configured to open and close a pressure medium connection between the hydraulic pump and a tank in controlled, continuous fashion. The cut valve is electrically activatable.

A load-controlled hydraulic supply for a utility vehicle includes a variable-displacement pump supplied with hydraulic fluid from a hydraulic reservoir. The variable-displacement pump has a mechanically actuable control slide for changing a volume flow delivered. An electrical actuator is configured to actuate the control slide. A controller is configured to control the electrical actuator in accordance with a determined load requirement on a consumer side.

The present invention relates to an electronically controlled valve for a variable displacement pump, a hydraulic pump and a hydraulic pump system with switchable control functions. Multiple control functions of different types of hydraulic pumps can be implemented via one single electronically controlled valve combined with control elements and sensors. The hydraulic pump systems can be easily integrated into the overall application systems for intelligent control.

Disclosed are a device and a method for controlling a hydraulic pump in a construction machine, the method including: checking whether a dynamic characteristic of an engine deviates from a predetermined permissible range when a load is applied to the hydraulic pump and a pump load reaches pump torque required by the hydraulic pump; when the dynamic characteristic of the engine deviates from the predetermined permissible range, applying a pump load to the hydraulic pump so as to increase the pump torque to predetermined torque with a predetermined change rate; collecting information which is generated when the pump load is applied; generating a new torque change rate map by generating a torque change rate for each load section based on the information collected in the information collecting step; and updating an existing torque change rate map to the new torque change rate map generated in the map data generating step.