Patent ID: 7634961

Claim:
A hydraulic circuit for a construction machine comprising: a hydraulic actuator; a control valve of a hydraulic pilot type, the control valve controlling the operation of the hydraulic actuator; at least one pilot line guiding a pilot pressure to at least one pilot port of the control valve; at least one pressure-reducing valve supplying a secondary pressure according to an operation amount of operating means to the pilot line as the pilot pressure; a pilot hydraulic source serving as a primary-pressure source of the pressure-reducing valve; a pump line supplying the primary pressure from the pilot hydraulic source, without bleed-off for pressure limitation, to the at least one pressure-reducing valve; a first throttle disposed upstream of the pressure-reducing valve for reducing the primary pressure that is supplied from the pilot hydraulic source to the pressure-reducing valve; a bleed-off line connected to the at least one pilot line and connecting the pilot line with a tank; and a second throttle disposed in the bleed-off line for moderating a rise in the pilot pressure that is supplied to the pilot port of the control valve.