DEVICE FOR EXHAUST GAS CLEANING DEVICE FAULT DIAGNOSIS Russian patent published in 2017 - IPC F01N3/08 F01N3/20 

FIELD: engines and pumps.

SUBSTANCE: fault diagnosis device comprises an exhaust gas cleaning device positioned in an exhaust passage of internal combustion engine and including a SCR catalyst; a feeding device supplying an additive, such as ammonia, to an exhaust gas cleaning device; EGR device providing recirculation of exhaust gas part from the exhaust passage on the downstream side of the additive feeding position into the inlet channel; obtaining means for obtaining the amount of NO_x inflow in the exhaust gas cleaning device using a parameter indicating the operating state of the internal combustion engine; a diagnostic tool for diagnosing a fault in the exhaust gas cleaning device using the calculated NO_x influx as a parameter; and correction means for upward correction of the calculated amount of NO_x inflow according to the amount of the additive recycled together with the exhaust gas when a exhaust gas portion is recirculated.

EFFECT: higher accuracy of fault diagnosis.

4 cl, 6 dwg