Fatigue Life Analysis Of Thermal Structure Coupling Of Clutch Diaphragm Spring

In the actual use of the process of diaphragm spring clutch,because the temperature is higher in front of transmission box body,and the clutch is separated and combined with repeated sliding,which leads to the temperature rise of the clutch,Which makes the diaphragm spring are affected by temperature,so fatigue failure occurs in advance,which seriously affects the safety and reliability of the automobile.Therefore,it is of great significance to study the real life of diaphragm spring under various factors.In this paper,the parametric modeling of clutch cover assembly is carried out in workbench,the temperature field of diaphragm spring is established under different temperature conditions,finite element method is used to simulate of thermal structure coupling of the diaphragm spring,the stress-deformation curves of diaphragm spring under different temperature conditions are analyzed,and obtain the fatigue damage point of the diaphragm spring,using the method of nominal stress analysis,considering the influence factors of the fatigue life,modified S-N curve of material,obtain the S-N curve of the diaphragm spring,and the fatigue life of the diaphragm spring under different temperature conditions is calculated by the stress value of finite element analysis.On the basis of the stress distribution in the structure simulation of the nonlinear contact,using DOE optimization analysis module in workbench,by response surface analysis,obtain the influence of different structure parameters on the fatigue life of the diaphragm spring,finally obtain the structure parameters of the least fatigue life of the diaphragm spring by the nonlinear programming optimization algorithm.The mechanical system,measuring and controlling system of the clutch diaphragm spring fatigue life test bench is designed,The program of host computer and slave compute is completed.the test bench is powered by the Schneider servo motor,and the rotary motion is converted to linear motion by an electric cylinder to simulate the release bearing to realize the separation of the clutch.Test bench using Advantech IPC as the host computer system,using LabWindows as software development platform to develop measurement and control software to realize data measurement and control of test stand,using Schneider m218 as the slave system to control the rotation of the servo motor.the host system and the slave system communicate by Ethernet,heating the clutch by hot-air gun,to simulate the temperature field of diaphragm spring,the stress values near the fatigue failure point of diaphragm spring under different temperature conditions are measured by sticking strain gauges on the diaphragm spring separation finger,The fatigue life of diaphragm spring is calculated by S-N curve.finally using test bench complete fatigue life test of diaphragm spring when the separation distance is 6mm,the simulation results are verified.