Air flow rate measuring device for an internal combustion engine

摘要

An air flow rate measuring device for an internal combustion engine is disclosed. The air flow rate measuring device has a casing provided downstream from an air cleaner element for purifying intake air to the internal combustion engine, a duct connected fluidly to and downstream from the casing, and an air flow meter provided in said duct, for measuring an air flow rate taken into the internal combustion engine. A cross-sectional area of a connection portion between the casing and the duct, taken perpendicularly to the direction of air flow is the minimum cross-sectional area in the duct.