Sequential operation of linear boom cranes Hydraulic cylinders

摘要

The present invention relates to a sequential hydraulic cylinder of a straight type boom cranes, comprising a direction switching valve (1) for switching the direction of a flow path, a cylinder part (2) operated by supplying pressure oil from the switching valve (1) And a sequential control section 3 for sequentially controlling the operation of each cylinder section 2. The cylinder section 2 is connected to piston rods 4a and 4b to which one side is fixed and cylinder housings 5a and 5b And the piston rods 4a and 4b are in the form of a double structure having outer piston rods 6a and 6b and inner piston rods 7a and 7b, And the valve block 14 of the sequential operation portion 3 is connected to the first-stage cylinder housing 5a, And the piston rod 4b of the two-stage cylinder is fixed to the valve block 14, The structure of the valve 14 and the valves 16 and 17 provided in the block 14 can increase the cross-sectional area of the flow path, thereby simplifying the structurally enlarged forward and rearward valves and structures, Thereby increasing the cross-sectional area of the flow passage and reducing the hydraulic pressure loss.