Secondary air supply device for engine exhaust system

摘要

Secondary air fed to the exhaust system of an engine is controlled by controllably venting the secondary air passing through a secondary air supply conduit leading to the exhaust system using a diaphragm unit operated valve. Vacuum applied to the diaphragm unit is controlled by cooperation of the venturi vacuum and the pressure differential between two interior portions of the secondary air supply conduit to supply the exhaust system with an appropriate amount of secondary air to the exhaust gas amount.