EXHAUST GAS RECIRCULATION CONTROL DEVICE FOR ENGINE OF WORKING MACHINE

摘要

PROBLEM TO BE SOLVED: To provide an exhaust gas recirculation control device for an engine of a working machine, actualizing the control of an EGR control valve corresponding to a current loaded condition of the engine with no fuel injection control assistance. SOLUTION: The control device comprises a bypass line 12 for guiding to a combustion chamber of the engine 1 part 15 of exhaust gas to be guided to an exhaust line 6 and the EGR control valve 17 for controlling the flow rate of the exhaust gas in the bypass line 12. It has a first computing means 25d1 for finding pump torque Tp and maximum engine toque Te and finding an engine load factor Tp/Te as the ratio of the pump torque Tp to the maximum engine torque Te, a second computing means 25d2 for finding a corresponding EGR factor from a relationship between a preset engine load factor and an EGR factor and the engine load factor found by the first computing means 25d1, and an output means 25b for outputting a drive control signal corresponding to the EGR factor found by the second computing means 25d2 to the EGR control valve 17. COPYRIGHT: (C)2005,JPO&NCIPI