| 摘要 |
PURPOSE:To effectively utilize an output, by enabling the output of an engine in each mode to be changed along an equal horsepower curve, in the case of the engine in which absorptive torque of a variable displacement oil hydraulic pump is changed in accordance with each mode by switching a preset output of the engine into plural modes. CONSTITUTION:An engine 1, driving variable displacement pumps 2a, 2b to supply their delivery oil to actuators 3a, 3b through valves 4a, 4b, controls each pump 2a, 2b by servomotors 5a, 5b through control valves 6a, 6b connected with a delivery side of the pumps. Each servomotor 5a, 5b is controlled by a control unit 7 in accordance with an operational condition of the engine. Here the control unit 7 is constituted so as to control an output of the engine in each mode to be changed along an equal horsepower curve in an equal fuel consumption range when absorptive torque of said pumps 2a, 2b is changed in accordance with each mode by switching a preset output of the engine 1 into plural modes. |
