Valve Train Dynamics Test System Development And Experiment Research

As an important part of the engine, the parts of valve train required good movement. To study dynamics of valve train played an important role in increasing engine power and reliability, improving fuel economy, reducing emissions and vibration noises of valve train. Valve train dynamics test is an essential part, and the test data is an important judgment in accordance with the valve train dynamic models, but there is rare dynamics test of the actual engine, test methods are not complete and enough rich. This paper based on the previous work, combined with engineering applications, developed the valve train dynamics test system and carried out test research in addition.The main contents and results are as follows.Designed valve train dynamics test system for a variety of engines, using a piezoelectric accelerometer to measure the valve acceleration, a laser sensor to measure the valve lift, timing belt as the drive link, to reduce the influence to dates from motor vibration in order to ensure test accuracy of the system.Based on the electrical environment of the valve train dynamics test systems, analyzed the sources of electromagnetic interference, and the electromagnetic compatibility design solved the electromagnetic interference problem effectively.Designed dynamic data acquisition and processing programs by Lab VIEW, the main features include digital filtering, multi-cycle average, zero drift elimination of acceleration and acceleration integral. The programs can complete the test data acquisition and post-processing quickly and accurately.Finished the test of the valve train dynamics of a typical engine to verify the function of the system, tested the stiffness of the valve train and the seating acceleration and analyzed the test date, found the main influences of valve seating characteristics are the actual valve seating position and the peak of acceleration. And the improvement measures were proposed for the valve train.