INTERNAL COMBUSTION ENGINE WITH CONTROL SYSTEM FOR SECONDARY AIR SUPPLY

摘要

An exhaust pressure responsive flow control valve is disposed in a secondary air supply passageway leading from the atmosphere to engine exhaust system. The valve has a valve member of a material which is movable by influence of magnetic fields and an electromagnet means for urging the valve member toward a valve closed position upon passing of electric current therethrough. First circuit means is provided which permits a relatively large current through the electromagnet when the exhaust gas temperatures are so high as to overheat the exhaust reactor or converter closing the valve to block secondary air supply through the passageway. Second circuit means is provided which permits a relatively small current through the electromagnet at normal stable operating conditions of the engine to restrict secondary air supply. At acceleration when a relatively large amount of secondary air is required no current is permitted through the electromagnet to open the valve.