HYDRAULIC CONTROL CIRCUIT SYSTEM

摘要

SPECIFICATION HYDRAULIC CONTROL CIRCUIT SYSTEM A hydraulic control circuit system comprises first and second double-acting cylinders, a hydraulic pump for supplying the double-acting cylinders with pressure oil, and directional control valves respectively associated with the cylinders for controlling the supply of pressure oil to the latter. The hydraulic control circuit system has a circuit for independently operating the individual cylinders and also a circuit for causing the rod advancing and retracting actions of the first cylinder to be followed by the rod advancing and retracting actions of the second cylinder. The system is applied to the hydraulic control circuit of, e.g., a front loader for controlling a hydraulic cylinder used for lifting and lowering the loader arm and another hydraulic cylinder used for turning the bucket pivotally connected to the free end of the arm. In that case, the system ensures that the upward and downward movements of the arm are followed by the turning of the bucket so as to prevent the load in the bucket from spilling, which would be otherwise caused by the tilting of the bucket with respect to the horizontal.