| The injector is composed of nozzle and many other components, which is one of the most important parts that decide the performance of the engine. The performance directly affects the economy, power performance and emission behavior. The matched running-in must be carried out before using for the purpose of getting quality at high level. We must do the study and development in detection device and system used for matched running-in.Based on the VI technology, the thesis develops the automatic detection system according to the actual needs. It pays emphases on the running-in of limited times, detecting the supply pressure of oil and the abstraction of character about the pressure wave.First, it realizes the intercommunication between Matlab and Digital Oscilloscope through the RS-232 serial interface. We use Matlab to read the data collected by Digital Oscilloscope and do wavelet transform, from which we can get signal bandwidth. It affords the bases for later development. Second, we design the circuit of signal adjustment according to the bandwidth of the signal frequency and dispose the analog signal before it is collected by data collection card. Third, we put the signal into computer by ADVANTECH data acquisition card PCI-1710HG. We apply Matlab in wavelet transform, abstract characters of the pressure signal through digital filtering and time domain analysis. It affords bases to judge the performance of the products. The time of running-in will be displayed in LED real-timely. The data collected will be stored in ACCESS data base for people to print, browse and so on. It realizes the function of the virtual oscilloscope through the playback of the wave shape by Matlab and Matcom.The experiment results indicate that the system has good stability, reliability and maintainability, avoids the subjective factors, reduces labor intensity and saves cost. It means a lot to production, detection and study of the injector.
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