| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent extreme speed down of a main body side actuator by supplying sufficient hydraulic fluid flow amount to the main body actuator even when a pressure of an attachment circuit of a hydraulic excavator gets close to a relief pressure. SOLUTION: In an interlocking operation of an attachment of a hydraulic excavator and other main body side actuator, when pressure of an independent attachment circuit 37 controlling an attachment gets close to a relief pressure, a controller 71 detecting pressure increase condition thereof by a pressure sensor 66 switches an electromagnetic selector valve 68 to a passage connection condition and prioritized flow amount dividing from a pressure correction type flow divider valve 38 to an external passage 67 flows out to a tank 39 via the electromagnetic selector valve 68. A pump 33 increases discharge flow amount in proportion as discharge pressure decreases, much fluid flow is supplied to the main body side actuator main circuit 36 from an independent attachment circuit 37 to prevent an extreme delay of speed of main body side actuator.</p> |
