Abstract: An engine control device is provided including: detection units for detecting a driving state of a work machine using a generator, target engine speed setting units for causing, on the basis of the driving state, a target engine speed set for a case where electric power generation by the generator is OFF to be the same as a target engine speed set for a case where the electric power generation by the generator is ON, and engine target output calculation units for calculating an engine target output during electric power generation OFF that can be output at most when the electric power generation by the generator is OFF, and calculates an engine target output obtained by adding an output corresponding to an electric power generation amount by the generator to the engine target output when the electric power generation by the generator is ON.

Abstract: An engine control device is provided including a detection unit for detecting the operating state of a working machine; a no-load maximum speed computation unit for computing a no-load maximum speed being an engine speed to be increased to the maximum upon a load of the working machine being released, based on the operating state; a target matching speed computation unit for computing a target matching speed being an engine speed to be increased upon a load being applied to the working machine, separately from the no-load maximum speed, based on the operating state; a target engine output computation unit for computing target engine output EL that can be outputted to the maximum, based on the operating state; and an engine control unit for controlling the engine speed between the no-load maximum speed and the target matching speed under a restriction of the target engine output.

Abstract: An engine control device is provided including: detection units for detecting a driving state of a work machine using a generator, target engine speed setting units for causing, on the basis of the driving state, a target engine speed set for a case where electric power generation by the generator is OFF to be the same as a target engine speed set for a case where the electric power generation by the generator is ON, and engine target output calculation units for calculating an engine target output during electric power generation OFF that can be output at most when the electric power generation by the generator is OFF, and calculates an engine target output obtained by adding an output corresponding to an electric power generation amount by the generator to the engine target output when the electric power generation by the generator is ON.

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 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.