On-board detection of state of IC engine exhaust catalyser - increasing lean-rich cycle until exhaust gas probe signal indicates noticeable change to determine oxygen@ storage capacity

摘要

The periodically alternating occurrence of oxygen excess (lean) and deficit (rich) in normal operation is successively and symmetrically, i.e. whilst maintaining the average value, increased until the change in the mixture composition is noticeable in the signal of an exhaust gas probe. The oxygen storage capacity is evaluated from the size of the increase. If the capacity is no longer sufficient a catalyser fault signal is generated. USE/ADVANTAGE - For reducing harmful internal combustion engine emissions. Does not have uncertainty of conventional techniques and enable reliable evaluation of catalyser quality.