| 摘要 |
PROBLEM TO BE SOLVED: To provide a construction machine capable of effectively generating back pressure, by preventing cavitation when operating specific hydraulic actuators with a simple circuit constitution. SOLUTION: This construction machine has a plurality of hydraulic actuators 1 to 4, operation levers 26 and 27 for operating the respective hydraulic actuators, a return oil passage 15 for returning return oil from the respective hydraulic actuators to a tank, regenerating lines 18 and 20 arranged in this return oil passage and resupplying a part of the return oil to the specific hydraulic actuators 2 and 4, a flow control valve 24 for controlling a regenerating flow rate resupplied to the hydraulic actuators by these regenerating lines, and a controller 25 for controlling this flow control valve. This controller 25 is characterized by being constituted so as to control the flow control valve 24 in the direction for increasing the regenerating flow rate as an operation quantity becomes large and reducing the regenerating flow rate by leaving delay time when stopping operation, when operating the operation levers 26 and 27 for operating the specific hydraulic actuators. COPYRIGHT: (C)2005,JPO&NCIPI |
