DRIVE CONTROL DEVICE FOR DRAGLINE WORKING MACHINE

摘要

PROBLEM TO BE SOLVED: To keep proper a load working on a winch of a dragline working machine. SOLUTION: A click 11c is made to bite into the ground by winding up and driving a main winding drum 6a in accordance with winding-up manipulated variable of a main winding lever 16B and consequently by pulling a bucket 11 to the side of a working machine by winding up a drag rope 6b. Hereby, a control signal is output from a controller 20 to an electromagnetic proportional decompression valve 18 when a main winding load L main detected by pressure sensors 31B, 31D provided in the front and the back of a hydraulic motor 12B exceeds a load Lmax set by a load setter 34. Consequently, a hoist rope 5b is wound up and the bucket 11 rises, and biting of the bucket 11 is avoided.