Patent ID: 8640451

Claim:
An engine control device comprising: at least one variable displacement hydraulic pump which is driven by an engine; at least one hydraulic actuator which is driven by discharge pressure oil from the variable displacement hydraulic pump; a control valve which controls the pressure oil discharged from the variable displacement hydraulic pump and supplies and discharges the pressure oil to and from the hydraulic actuator; and pump displacement detecting means for detecting a pump displacement of the variable displacement hydraulic pump, wherein the engine control device is characterized by further comprising command means for selecting and commanding one of command values that can be variably commanded, and setting means for setting a first target engine speed in accordance with a command value commanded by the command means, and setting a second target engine speed which is lower than the first target engine speed based on the set first target engine speed, wherein when the pump displacement detected by the pump displacement detecting means increases and exceeds a first predetermined pump displacement when the engine is controlled at an engine speed which is lower than the first target engine speed based on the second target engine speed, a target engine speed is changed from the second target engine speed to a third target engine speed which is higher than the second target engine speed and which is equal to or lower than the first target engine speed.