| 摘要 |
Provided is a hydraulic drive system for a hydraulic working machine, which can surely set a delivery pressure at a preset value upon raising a temperature of exhaust gas to a temperature needed for combustion of particulate matter by increasing a load to be applied to an engine. In a non-operation state of the hydraulic working machine, a variable restrictor (19) is controlled by a controller (14) and a delivery pressure control valve (20) to increase a delivery pressure of a variable displacement hydraulic pump (4), so that the load to be applied to the engine is increased to raise the temperature of exhaust gas to the temperature needed for the combustion of the particulate matter. At this time, a controller (14) controls the delivery pressure control valve (20) such that a delivery pressure to be detected by a delivery pressure sensor (21) will conform with a preset reference delivery pressure. The reference delivery pressure has been set as a minimum pressure that can provide the exhaust gas with heat needed for the combustion of the particulate mater. |
