| 摘要 |
PURPOSE:To prevent the fuel from over rich at the time of possible error sensing of the intake air amount of forming a by-pass leading from the intake air amount sensor till a throttle valve, and by introducing fresh air directly from this by-pass passage during extra low rotation of engine or in the event of stall after no-load charging. CONSTITUTION:A by-pass 8 to introduce fresh air to the engine through an intake air amount sensor 2 and a throttle valve 3 is formed in the intake passage 1 of the engine, and a solenoid operated valve 10 operating under command from a control circuit 9 is interposed in this passage 8. This control circuit 9 has comparators 12-14, into which the output from a number-to-revolutions sensor 11 is placed in, and there a comparison is performed of actual number-of-revolutions signal with the output signals from a setting value generator 15 which gives out respective setting values N1-N3 (N1<N2<N3). The output of an OR circuit 18 is impressed to the valve 10 through a mono-multi 21 and an amplifier 22 upon processing the outputs of each comparator 12-14 with the OR circuit 18, AND circuit 19 and mono-multi 20. |
