Patent ID: 7716920
Filing Date: 2010-05-18
Classification: F02D,F02M,Y02T

Abstract:
1. An engine exhaust gas purification device comprising: a filter provided in an exhaust passage of an engine, for trapping particulate matter contained in exhaust gas; a catalyst provided on at least one of an upstream side of the filter and a surface of the filter, for regenerating the filter; an EGR valve provided in an EGR passage linking an intake side and an exhaust side of the engine; an injector for injecting fuel into a cylinder of the engine; and control means for determining when the filter needs to be regenerated and for controlling the injector and the EGR valve; wherein, upon a determination that the filter needs to be regenerated, the control means forcibly regenerate the filter by controlling the injector to switch from performing normal injection when fuel injection is carried out to performing fuel injection that supplies unburned fuel components to the filter when fuel injection is carried out; and wherein the control means fully close the EGR valve during forcible regeneration while supplying unburned fuel components and open the EGR valve during forcible regeneration when fuel injection is not carried out, upon a request for speed reduction, so as to scavenge the EGR passage by air which is not mixed with fuel.