Research Of Control Svstem Of Automotive Engine Timing Chain Wear Test Rig

With the development and expanding of automobile industry, more and more cars with higher performance have been produced. As the key component of cars, automobile engine to a large extent decides the performance level of them. Timing system is the time control unit of valve mechanism, which plays an important role in the operation of engines. Now, timing belts are gradually replaced by timing chains in foreign, and the domestic automobile manufacturers have developed more engines with timing chains adopted. However, there still exists a large gap between domestic level and foreign level in the research and production of timing chains, and presently exiting test equipment for timing chains is very poor. Therefore, it’s significant to develop new and integrated automobile timing chain wear test rig. This thesis mainly focuses on design and experiment of automobile engine timing chain wear test rig control system.In the first chapter, the basic operation principles of automobile engines and its valve mechanism were introduced, the function and development status of timing chain were stated. Then, the research status of timing chain wear and relative test technology were reviewed. Finally, the main content of this thesis was presented.In the second chapter, the mechanical structure of automobile engine timing chain wear test rig developed by our lab, and its primary parts were respectively discussed in detail.In the third chapter, the hardware part of automobile engine timing chain wear test rig control system was designed. Firstly, the overall design scheme of control system was identified. Then, the automotive control based on S7-200PLC and the acquisition of signal based on variable sensors were stated.In the fourth chapter, the software of automobile engine timing chain wear test rig was developed. The ladder diagram procedures programmed in STEP7-Micro/WIN was introduced in the form of flow diagram. And the SCADA and HMI of control system developed in ForceControl V7.0were stated.In the fifth chapter, to verify the effectiveness of the whole automobile engine timing chain wear test rig control system, a completed experiment scheme was made, which contained constant speed test and variable speeds test, and the test results of different experiments were compared and analyzed.In the sixth chapter, the thesis work was summarized and the further work was discussed.