Performance Research Of The Internal-Combustion Engine's Knock And The Knock Sensor

Knocking to the internal combustion engine (or striking to the piston) is one not ideal burning way. It will make the internal-combustion engine work violent, the power drop, the economy of the fuel become bad. Knock signal characteristic can be drawn by knock sensor and can be utilized to judge the knock to take place accurately and the knock's intensity size. It is great significant to utilized it to control the internal-combustion engine work in under the expectant knocking operating mode and it has the important application value and the project significance to enhance the internal combustion engine operating performance and lengthen the internal combustion engine service life by means of conducting the thorough research to the phenomenon of the internal combustion engine knock and the knock sensor.To offer the theory and experiment basis of the design of the knock sensor, analyzing from the theory, the function of the knock sensor is tested in this text. The knock production mechanism of signal, measure method and the knock signal characteristic are analyzed at first, and the theoretical foundation of digitized processing of the knock signal is discussed.Through the research of the knock sensor structure and operation principle, the knock sensor's main performance index have been analyzed in detail, the sensitivity, frequency responding, phase responding , range and so on the static and dynamic performance parameter.Carried on performance measure knock sensors, 4 type of 8 knocks sensor's responds function of the frequency sensitivity, linear degree, etc are measured and analyzed. Then deficiency of domestic knock sensor is found out and according to which the better performance has, one new-type of designing plan of knock sensor is designed to provide the development basis to speed up the productiondomesticization process of the knock sensor.The structure of the new designed sensor is very compact, the cost is relatively low and it is small to take up the space. Its signal does not need to amplify while measuring the signal of knock. So it is very suitable for domestic production.