Hydraulic control device of a working machine

A hydraulic control device for a working machine comprising:

• a hydraulic pump driven by a power source;
• actuators operated by pressure oil discharged from the hydraulic pump, said actuators including a swing motor;
• a control valve for controlling a flow rate and a direction of the pressure oil discharged from the hydraulic pump;
• an operating member for switching and operating the control valve;
• a bleed-off oil path for bleeding off a part of the pressure oil supplied to said swing motor;
• a bleed-off amount adjusting means for adjusting a bleed-off amount provided in the bleed-off oil path;
• an operating amount detecting means for detecting an operating amount of the operating member;
• and
• a control means for setting the bleed-off amount according to the operating amount detected by the operating amount detecting means and controlling the bleed-off amount adjusting means according to the bleed-off amount set.