| 摘要 |
PROBLEM TO BE SOLVED: To provide a control device of a hydraulic circuit and a control method of the hydraulic circuit, capable of keeping operability and flow rate characteristics of an actuator even when an engine speed mode is changed in a virtual bleed-off hydraulic system.SOLUTION: A control device of a hydraulic circuit includes a virtual discharge flow rate setting portion for setting a virtual discharge flow rate of a variable capacity pump to a prescribed value, an actuator flow rate calculating portion for determining the total estimated actuator flow rate to all of the actuators as a prescribed value determining a rotating speed of the variable capacity pump in advance, a bleed-off flow rate calculating portion for calculating a virtual bleed-off flow rate from all of direction control valves on the basis of control input to each direction control valve, and a pump control portion determining a virtual discharge pressure on the basis of the difference obtained by subtracting the total estimated actuator flow rate and the virtual bleed-off flow rate from the virtual discharge flow rate, and controlling the variable capacity pump on the basis of the virtual discharge pressure.SELECTED DRAWING: Figure 4 |
