Thermal resistor type air flow measuring apparatus

摘要

The invention relates to a thermal resistor type air flow measuring apparatus for correcting properly the error caused by the pulsation in the intake pipe in detecting the air flow of the internal combustion engine, using a passage (11, 12, 14) in which a thermal resistor (3, 4) is placed inside the auxiliary air passage into which the reverse flow (24) hardly flows directly and preventing the error caused by the reverse flow, the existence of the reverse flow (24) is judged by the ratio of the amplitude to the mean value using the maximum value, the minimum value and the mean value of the forward air flow (23) waveform, as well as the error caused by the increase of the forward air flow (23) is corrected.