| 摘要 |
<p>PURPOSE:To perform cooperation work of two actuators efficiently by supplying working oil of the 2nd hydraulic circuit directly to an actuator of the 1st hydraulic circuit. CONSTITUTION:A return side 27a of a relief valve 27 in a 2nd hydraulic circuit 20 and a pressure port 6a of a switching valve 6 of a water pump 7 in a 1st hydraulic circuit 9 are made to flow together via a confluence line 30. In the case a switching valve 2 is switched to the pump 7 side, the working oil sent from the 1st and 2nd hydraulic pumps 1, 2 may also be made to flow together to be supplied to the water pump 7. In case the switching valve 2 is switched to a swing cylinder 3 side, the water pump 3 may be concurrently operated with the swing cylinder 3.</p> |
