| 摘要 |
<p>PURPOSE: To obtain a heating type air flow rate measuring device having good measuring accuracy even to a dynamic air flow condition by providing output, memory and calculation means and also providing a correction means which corrects a reverse side air flow rate conversion function before the calculation means converts a reverse flow signal to an reverse air flow rate. CONSTITUTION: Reverse flow of an air flow in a passage is detected. Before correction of air flow rate to the reverse flow is executed, a reverse side air flow rate conversion function, i.e., a reverse flow map (flow rate map of the reverse side) for converting a signal from a heating resistor into the air flow rate is corrected. Then, the air flow rate upon the occurrence of the reverse flowing is corrected in two steps by utilizing the corrected reverse flow map. Thereby, it is possible to improve the measuring accuracy of a heating type air flow rate measuring device. Thus, the corrected reverse flow map that the map represented by static characteristics is changed beforehand to the map suitable for a dynamic air flow condition is used so that it is possible to obtain the heating type air flow rate measuring device having good measurement accuracy to the dynamic air flow condition.</p> |
