OPERATING CIRCUIT OF CONSTRUCTION EQUIPMENT

摘要

PROBLEM TO BE SOLVED: To prevent a wrong operation in an operating circuit that uses an operating lever of turning and boom swing in common and has a mode in which pilot pressure is switched via a selector valve. SOLUTION: This operating circuit comprises a changeover switch 51 for supplying a switching signal to the selector valve, pressure switches 21a and 21b for detecting whether or not the pilot pressure is introduced from a remote control valve 19, and a changeover control circuit 18 for switching a switching destination of the selector valve 17 to a boom swing cylinder 15 side when the changeover switch 51 outputs the switching signal, and for holding the switching destination at the boom swing cylinder 15 side when the pilot pressure is detected by the pressure switches 21a and 21b.