| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a pump control device of a construction machine which can effectively make use of engine output and which does not result in a decrease in the amount of work even when three variable displacement hydraulic pumps are used and the discharge pressure of one of the three hydraulic pumps is reduced by a pressure-reducing valve, and when the input torque of the other two hydraulic pumps is reduced. <P>SOLUTION: The pump control device of a construction machine is provided with a torque correction amount output part T2, a standard torque output part T1, and a calculation part. The torque correction amount output part T2 outputs the correction torque amount of a second pump based on a discharge pressure Pd3 of a third pump which is detected by a pressure detection means 30. Then the standard torque output part T1 outputs the standard torque values of the first and second pumps based on a target revolution number of a prime mover instructed by the instruction means. The calculation part calculates a torque control instruction pressure based on the output values Td3, Te, and the torque control instruction pressure increases the input torque of the second pump. Then the torque control instruction pressure is fed to the variable mechanism of the regulator for the second pump as an external instruction pressure, thus the input torque of the first and second pumps are not reduced more than necessary. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
