| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a hydraulic control device used for a construction machine capable of suppressing or extinguishing the pulsation of pressure oil discharged from a hydraulic pump. <P>SOLUTION: The hydraulic control device for a construction machine comprises a plurality of hydraulic circuits each having a hydraulic pump, an actuator, and a first selector valve arranged between the hydraulic pump and the actuator, the hydraulic pump and the first selector valve of each hydraulic circuit connected to each other via a connection oil path, a communication oil path for interconnecting the connection oil paths of the hydraulic circuit parts, and a second selector valve for engaging and disengaging pressure oil with and from the communication oil path. The hydraulic pumps arranged in the hydraulic circuits discharge the pressure oil with predetermined mutual phase differences. The second selector valve is changed over into a shut-off position where part of the pressure oil in the communication oil path can be distributed in one or both directions when independently operating the hydraulic circuits. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
