Patent ID: 6378303
Filing Date: 2002-04-30
Classification: E02F,F15B

Abstract:
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.