| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To prevent the excessive rotation of a traveling motor in single-traveling composite operation by dividing traveling composite operation for carrying out traveling operation and working operation at the same time into single-traveling composite operation and double-traveling composite operation. <P>SOLUTION: This hydraulic control device for a construction machine is configured to obtain a second pressure oil supply state of supplying a part of discharge oil from a first pump 19 to the traveling side through a communicating passage 30 while driving working actuators 6, 7, 8, 12 by the first pump 19 and driving both traveling motors 10, 11 by a second pump 20 in double-traveling composite operation out of the traveling composite operation, and to obtain a third pressure oil supply state of closing the communicating passage 30 from the second pressure oil supply state and supplying the discharge oil from the first pump 19 to the traveling motors 10, 11 and the discharge oil from the second pump 20 to the working actuators 6, 7, 8, 12 independently in single-traveling composite operation. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
