Patent ID: 7610755

Claim:
A hydraulic control apparatus of a working machine having a hydraulic circuit, the circuit comprising: a hydraulic pump; a hydraulic actuator driven by the hydraulic pump as a driving source; a control valve for controlling supply and discharge of oil with respect to the hydraulic actuator; a relief valve for setting a maximum pressure of the hydraulic circuit; and a controller having: selecting means for selecting, as a flow rate command value, a smaller one of a pressure feedback control for controlling the pump flow rate based on a set pressure as a cutoff pressure and a pump pressure, and an ordinary control for controlling the pump flow rate based on operation information, and flow rate command value increasing means operative in a case that the pressure feedback control is selected by the selecting means, for increasing the flow rate command value with the passage of time, as compared to a flow rate command value under the pressure feedback control without the flow rate command value increasing means.