REDUCING AGENT FEEDER FOR EXHAUST EMISSION CONTROL CATALYST

摘要

PROBLEM TO BE SOLVED: To provide a reducing agent feeder for an exhaust emission control catalyst, improving fuel consumption by controlling such that a liquid reducing agent is maintained at a minimum appropriate temperature.

SOLUTION: A reducing agent tank 33 stores the liquid reducing agent supplied to the exhaust system 19 of an engine 15. A heat exchanger 35 is supplied with engine cooling water heated by heat exchange with the engine 15 and heats the liquid reducing agent in the reducing agent tank 33 through heat storage fluid 32. A radiator 18 cools the engine cooling water routed through the heat exchanger 35 and circulates it to the engine 15. The amount of engine cooling water returned from the engine 15 to the radiator 18 by bypassing the heat exchanger 35 is proportionally adjusted in a reducing direction by a solenoid proportional valve 38 when the amount of engine cooling water returned from the engine 15 to the radiator 18 through the heat exchanger 35 is proportionally adjusted in an increasing direction. A controller 43 adjusts the solenoid proportional valve 38 based on the temperature of the liquid reducing agent detected by a temperature detector 41 and controls the temperature of the liquid reducing agent constant.

COPYRIGHT: (C)2010,JPO&INPIT