| 摘要 |
PURPOSE:To enable accurate measurement of air intake, by forcibly setting the flow rate for the minimum flow rate value when there is undershoot in the deceleration to bring the measured value close to the actual value. CONSTITUTION:A flowmeter 24 is made up of a vortex generating body 26 set in an intake tube 16 located on the downstream of an air cleaner 18 and on the upstream of a throttle valve 20 and a vortex detecting unit 28. On the other hand, an input port 55 is connected to a comparator 40 to receive an air intake data and further, inputs engine state signals for the revolutions, water temperature of the engine and the like to control a fuel injection valve 22. then, as each signal is sent from the flowmeter 24, a counter is set for 100 msec, for example. If there is any undershoot, the counter will not be set for a long time. So, an interrupt routine is provided which is adapted to be executed at a time interval of, for instance, 4 msec, sufficiently shorter than the period of the undershoot. As a result, as the value of the counter becomes less than 0, the frequency of the pulse signal is fixed at the minimum value thereby calculating the air intake value corresponding thereto. |
