Patent ID: 7404291
Filing Date: 2008-07-29
Classification: F01N,Y02T

Abstract:
1. An exhaust gas purifying apparatus for an internal combustion engine, comprising: a filter provided in an exhaust system of said engine for trapping particulates in exhaust gases; an atmospheric temperature sensor that detects an atmospheric temperature; an exhaust gas temperature sensor that detects an exhaust gas temperature of said engine; a pressure difference sensor for detecting a pressure difference between an upstream side pressure of said filter and a downstream side pressure of said filter; non-frozen state determining means for determining a non-frozen state of said pressure difference sensor based on a first parameter corresponding to the detected exhaust gas temperature of said engine and a second parameter corresponding to the detected atmospheric temperature; and abnormality determining means for determining an abnormality of said filter using a determination result obtained by said non-frozen state determining means.