| 摘要 |
PURPOSE:To permit to effect stabilized control by a method wherein the value of wave height or the average value of a vibration wave of an internal-combustion engine in a predetermined operating area is compared with the maximum and minimum values of predetermined desired value and fail-safe control is effected when a range within the minimum and maximum values has been exceeded. CONSTITUTION:In the operating area, such as the area of idling operation for example, a waveform V1 is provided except the case in knocking area when a knock sensor 5 has a normal sensibility, therefore, the value of wave height of a signal A from a waveform shaping circuit 12 is supplied to a MCU9 through a sample hold means 13 and the value is compared with the maximum value VN1 and the minimum value VN2 of the desired value. In this case, the waveform V1 is within the range of limit values, therefore, a normal knock restricting control is effected. When the signal K from the knock sensor 5 is deviated from said range of limit values, it is judged that the sensibility of the knock sensor 5 is not suitable for the practical use and the predetermined fail-safe control is effected. |
