| 摘要 |
PURPOSE:To suppress a measured error within an allowable range at the low flow rate of fluid and the resistance of a flow course of a flow rate measuring range at its minimum at the high flow rate by closing a part of the flow course at the low flow rate and opening the flow course in accordance with the flow rate at the high flow rate. CONSTITUTION:A side wall 100 dividing an sucked air course is fitted to a throttle body 12, a flow rate sensor 104 is arranged on the flow course 102 and a stop valve 108 varying the quantity of sucked air flowing into the flow course 102 by interlocking with a throttle valve 22 is arranged in a flow course 106. A control device 80 calculates a correcting factor on the basis of detected outputs from an opening detecting switch 24 of the throttle valve 22 and an opening sensor 110 of the stop valve 108 and corrects the detcted output of the flow rate sensor 104 to calculate the volume of sucked air. When the volume of the sucked air is low, the measured error can be suppressed within the allowable range, and if the volume is increased, the resistance of the flow course is reduced by the stop valve 108, so that the volume of the sucked air into an engine can be measured highly accurately. |
