HYDRAULIC SYSTEM FOR HEAVILY EQUIPPED OPTIONAL DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a hydraulic system for a heavily equipped optional device miniaturizing a control valve assembly to reduce a prime cost and a production cost by supplying an operating fluid to the optional device without changing the structure of the control valve assembly in the case of additionally mounting the optional device to a crawler type small excavator.;SOLUTION: The hydraulic system for heavy equipment provided with a pilot pump at a main control valve is provided with a straight advancing travel control valve C4 for allowing the operating fluid discharged from a plurality of hydraulic pumps P2, P3 to join to be distributed and supplied to right and left traveling motors and cutting off the operating fluid supplied to the traveling motors when switching to the supply of pilot signal pressure Pil, and an optional device control valve C5 switched simultaneously with the straight advancing travel control valve C4 by the pilot signal pressure Pil to control the operating fluid supplied to another optional device A from the hydraulic pump P3 on one side.;COPYRIGHT: (C)2004,JPO&NCIPI