Patent ID: 7934369
Filing Date: 2011-05-03
Classification: F01N,Y02T

Abstract:
1. An exhaust gas purifying apparatus for an internal combustion engine, comprising: a recoverable type exhaust gas purifying device provided in an exhaust passage; a reducing agent addition device for adding a reducing agent into the exhaust passage upstream of the exhaust gas purifying device; an operation control device for controlling operation of the reducing agent addition device such that the reducing agent is added into the exhaust passage in a recovering process of the exhaust gas purifying device; a pressure obtaining device for obtaining a pressure in the exhaust passage downstream from the reducing agent addition device and upstream from the exhaust gas purifying device; and a diagnosing device for diagnosing the reducing agent addition device based on the pressure obtained by the pressure obtaining device at an estimate arrival-time when the reducing agent added from the reducing agent addition device is estimated to arrive at the exhaust gas purifying device in a case the operation of the reducing agent addition device is controlled by the operation control device such that the reducing agent is added into the exhaust passage.