Hot film type air flow quantity detecting apparatus applicable to vehicular internal combustion engine

摘要

In an apparatus for detecting airflow quantity applicable to a vehicular internal combustion engine, a slit is formed so that an insulating substrate is partitioned into a main substrate portion and a sub substrate portion. A first temperature sensitive resistor, a heat generated main resistor 31, and a second temperature sensitive resistor are formed on the main substrate portion in film forms in the order with respect to the forward air stream direction (A). A difference in the resistance values of the first and second temperature sensitive resistors 32 and 33 detects the air stream direction and detects the flow quantity according to a temperature variation (namely, the variation in resistance value) in the heat generated temperature sensitive main resistor due to the cooling caused by the intake air.