Intake air flow rate measuring device for internal combustion engine

摘要

A flow rate measuring device for an internal combustion engine with an unbalanced sensing vane pivotably disposed in an intake pipe upstream of a throttle valve, an actuating device having a pressure chamber and a movable diaphragm coupled to the sensing vane for actuating the same in response to a pressure applied to the pressure chamber, and a conduit communicating the pressure chamber with the intake pipe between the sensing vane and the throttle valve. The flow rate measuring device further has a pressure difference responsive valve responsive to a pressure difference across the sensing vane to compensate the pressure applied to the pressure chamber, whereby the pressure difference across the sensing vane can be kept constant irrespective of changes in the amount of intake air.