| 摘要 |
<p>PURPOSE:To enhance detection accuracy by calculating the average values of two detection signals by discriminating the signal of a part where the effect of a back flow does not reach on the basis of the difference between two detection signals corresponding to the predetermined cycle of a sampling cycle. CONSTITUTION:When an engine is within a low rotation high load region, an air sucking cycle T(=30/N wherein N is the number of rotations of the engine) is divided into (n)(= an even number between 10-100) equal sampling cycles DELTAt and a sucked air flow rate at every sampling cycle DELTAt is read as a detection signal Qa on the basis of the flow velocity detected by a hot wire element and the detection signals q1, q2 corresponding to the predetermined cycle of the detection signal Qa, for example, the half cycle T/2 of the cycle T. The signal difference di=q1-q2 between both signals q1, q2 is operated and, in the case of the absolute value of the signal difference di < predetermined value ds, the sucked air flow rate is operated and detected as Q=(q1+q2)/2. In the case of difference di > value ds, the signal difference di-1 of the signal previous by the cycle DELTAt is operated. When the codes of the differences di, di-1 are different, the sucked air flow rate Q can be detected from the average value of the detection signals q1, q2.</p> |
