EXHAUST GAS PURIFIER FOR ENGINE

摘要

PURPOSE:To enable an engine to always maintain an excellent emission property by correcting a fuel supply rate to the increasing side or the quantity of secondary air to the decreasing side after the quantity of secondary air is acceleratedly increased when the secondary air supplied to an exhaust system moves from a nonsupply area to a supply area. CONSTITUTION:A feedback control means 11 for controlling a fuel supplying means 10 is provided so that an air-fuel ratio of exhaust gas detected by an air-fuel ratio detecting means 4 may be set to a specified air-fuel ratio. And a feedback stopping means 13 is provided so that it stops control operation performed by a feedback control means 11 and corrects fuel supply rate to the increasing side when an accelerating condition is detected by an acceleration detecting means 12. Further, a correction means 14 is provided so that it outputs a correction signal to the fuel supply means 10 or a secondary air supplying means 8, and corrects the secondary air/fuel ratio of the exhaust gas to be introduced into a catalytic device 3 to the rich side by increasing the fuel supply rate or decreasing the quantity of secondary air at the time of starting the feedback after correcting the accelerating fuel when the secondary air moves from a non-supply area to a supply area.