Drive control method of hydraulic actuator of construction machine

A drive control method of hydraulic actuator for construction machine, including an electronic swing operation lever;

• an electronic working device operation lever;
• a variable displacement hydraulic pump;
• a swing motor and a hydraulic cylinder that is driven by hydraulic fluid of the hydraulic pump;
• first electric, proportional control valves at an inlet line and an outlet line of the swing motor for supplying and discharging the hydraulic fluid of the hydraulic pump, respectively;
• second electric proportional control valves at an inlet line and an outlet line of the hydraulic cylinder for supplying and discharging the hydraulic fluid of the hydraulic pump, respectively;
• and a controller to which operation signals are inputted by operating the swing operation lever and the working device operation lever, the method comprising;
• judging whether or not the swing operation lever and the working device operation lever are in combined operations;
• calculating a required pressure of the hydraulic cylinder corresponding to the operation amount of the swing operation lever;
• calculating a required flow rate of the hydraulic cylinder corresponding to the operation amount of the working device operation lever, and a required flow rate of the swing motor corresponding to the operation amount of the swing operation lever;
• calculating valve opening areas of the first and second electric proportional control valves at the inlet and outlet lines of the hydraulic cylinder or the swing motor using the required pressure and flow rate of the hydraulic cylinder and the swine motor, respectively;
• and,
• calculating electric current values inputted to the first and second proportional control valves at the inlet and outlet lines by comparing the valve opening areas of the first and second electric proportional control valves at the inlet and outlet lines with a predetermined data or a value of data table, respectively.