REDUCER SUPPLY DEVICE AND CONSTRUCTION MACHINE WITH REDUCER SUPPLY DEVICE

摘要

PROBLEM TO BE SOLVED: To address a problem that there is no preventing the breaking of equipment due to the freezing of a reducer.SOLUTION: A reducer supply device 2 comprises: an injector 13 that injects a reducer to exhaust gas of an engine 11; a reducer tank 15 that stores the reducer injected by the injector 13; a reducer conduit 20 that connects the reducer tank 5 to the injector 13 and is heated by engine cooling water; and a reducer pump 14 that supplies the reducer from the tank 15 to the injector 13 through the reducer conduit 20. A controller 30 has a first condition that an injection command quantity is smaller than a command quantity F1, a second condition that a temperature of the engine cooling water is lower than a temperature T7, and a third condition that a temperature of outdoor air is lower than a temperature T8, and controls the reducer pump 14 to rotate reversely to return the reducer present within the reducer conduit 20 to the reducer tank 15 when the first condition and at least one of the second condition and the third condition are satisfied.SELECTED DRAWING: Figure 1