Design Of Feeding System And Its Positioning Accuracy Of Cylinder And Cylinder Head Horizontal Machining Center

The machining quality of car engine cylinder block and cylinder head have a direct impact of engine power, fuel consumption and exhaust emissions, performance of feed system is one of key factors affecting the processing quality. By taking the horizontal feed system of car engine cylinder block, cylinder head machining center as the research example, the driving mode and the structure layout of the feed system were studied by computer simulation software. Then, the positioning error of the dual-screw-driving feed system was studied based on the dynamic modeling, simulation and thermal error test.Based on dynamics theory, equivalent models of the feed system were established, the equivalent transfer function of servo system and mechanical drive system were derived, and the key factors affecting the stability of the system was found. These provided a basis for the study of structure layout design and the positioning error of servo feed system.The natural frequency of mechanical system was chose as the optimization goal to do the finite element analysis. By taking the horizontal feed system of car engine cylinder block, cylinder head machining center as the research example, simulation models of single-screw-driving and dual-screw-driving were established, through the modal analysis of the driving mode of two kinds of vibration mode and natural frequency, got the optimal structure layout of the feed system.Based on the dynamics model, simulation models of dual-screw-driving were established based on MATLAB/Simulink. By taking the horizontal feed system of car engine cylinder block, cylinder head machining center as the research example, analyzed the key factors which affecting the positioning accuracy of the feed system; Then, nonlinear friction model was established to analyze the vulnerabilities of mechanical transmission system.Considering the complex heat transfer characteristics of the temperature field of feed system, it was difficult to accurately analyze its thermal characteristics and error by theoretical modeling and simulation. By taking the horizontal feed system as the research object, a kind of thermal error test system was established, screw temperature field and thermal error was studied. At the same time, integrated forecast model was established based on the experimental data, provided a reference for the later thermal error compensation.