Abstract: In a work machine, a control unit controls a pilot control valve for controlling the opening area of a first direction switch valve in executing the combined operation to be less than or equal to that in executing a single operation. The combined operation represents an operation of simultaneously operating first and second actuators. The single operation represents an operation of operating only the first actuator. Further, the control unit determines the opening area of the first direction switch valve in the combined operation based on a hydraulic pressure detected by a hydraulic pressure detector unit.

Abstract: In a hydraulic excavator, a controller is configured to control output of an engine based on a first engine output torque line that defines an upper limit for engine output torque against engine rotation rate. The controller is configured to determine which of two operations, a high hydraulic load operation in which a work machine is subjected to a high hydraulic load and a low hydraulic load operation in which the work machine is subjected to a low hydraulic load, is being performed. When swinging for a revolving unit and the low hydraulic load operation for the work machine are being performed as a combined operation, the controller is configured to control the output of the engine based on a second engine output torque line. The second engine output torque line is an engine output torque line with a lower engine output torque than the first engine output torque line.

Abstract: A control unit is configured to calculate a target absorption torque of a hydraulic pump at which the engine output torque and the absorption torque of the hydraulic pump match a target matching rotation speed of the engine. The control unit is configured to refer to command data, calculate a command current value corresponding to the target absorption torque, and output a command signal of the calculated value to a pump control device. The control unit is configured to calculate the absorption torque at calibration points at which there is an equilibrium state in which the output horsepower of the engine and the absorption horsepower of the hydraulic pump are matched. The control unit is configured to acquire calibration information including the calculated absorption torque and the command current value output to the pump control device in the equilibrium state, and calibrate the command data based on the calibration information.

Abstract: A control unit is configured to calculate a target absorption torque of a hydraulic pump at which the engine output torque and the absorption torque of the hydraulic pump match a target matching rotation speed of the engine. The control unit is configured to refer to command data, calculate a command current value corresponding to the target absorption torque, and output a command signal of the calculated value to a pump control device. The control unit is configured to calculate the absorption torque at calibration points at which there is an equilibrium state in which the output horsepower of the engine and the absorption horsepower of the hydraulic pump are matched. The control unit is configured to acquire calibration information including the calculated absorption torque and the command current value output to the pump control device in the equilibrium state, and calibrate the command data based on the calibration information.

Abstract: In a hydraulic excavator, a controller is configured to control output of an engine based on a first engine output torque line that defines an upper limit for engine output torque against engine rotation rate. The controller is configured to determine which of two operations, a high hydraulic load operation in which a work machine is subjected to a high hydraulic load and a low hydraulic load operation in which the work machine is subjected to a low hydraulic load, is being performed. When swinging for a revolving unit and the low hydraulic load operation for the work machine are being performed as a combined operation, the controller is configured to control the output of the engine based on a second engine output torque line. The second engine output torque line is an engine output torque line with a lower engine output torque than the first engine output torque line.

Abstract: In a work machine, a control unit controls a pilot control valve for controlling the opening area of a first direction switch valve in executing the combined operation to be less than or equal to that in executing a single operation. The combined operation represents an operation of simultaneously operating first and second actuators. The single operation represents an operation of operating only the first actuator. Further, the control unit determines the opening area of the first direction switch valve in the combined operation based on a hydraulic pressure detected by a hydraulic pressure detector unit.