Optimization Design Of Clutch Damping System On One Small Vehicle

Drive line system of FR vehicle is working with multi degree of freedom,torsional vibration transmit through the structure and air then cause body panel vibration,gearbox rattle problem and so on,it's the main problem of vehicle NVH.Clutch torsional vibration damper as an important damping parts of transmission system,it play an important role by reasonable parameters matching and calibration to improve the NVH problems of drive line.This paper taking a economical FR MPV vehicle as the research object,in view of the subjective evaluation of the interior noise problem,a torsional vibration model of the drive line was built for analysis.Based on the mathematical models with 13 degrees of freedom,and taking gear 3 and gear 5 WOT working condition for example,the natural frequency of free vibration and vibration mode of system was analysed,the results show that the 2,3 order natural frequency of system are close to the 2,3,4 order frequency of engine,the 2,4 order frequency of engine are the main order,there is a resonance risk in drive line.Model was also used to take forced vibration analysis,the analysis shows that in gear 3 WOT condition,the drive line system resonance when the engine speed is 1916 RPM,the frequency which corresponds to the 2 order natural frequency of drive line,and in condition of gear 5 WOT there is no risk of resonance.At last,the vibration data was collected by Rotec torsional vibration analysis system,and compare the measurement results with the model simulation results,verify the accuracy of the model analysis.Then the influence of changed clutch parameter by forced vibration was discussed,and compared the influence by nine groups of different stiffness and damping of clutch by forced vibration,the results showed that under the increase of stiffness but with the same damping value,the damping effect of clutch become worse and the corresponding resonance speed of system also increase.But in the case of constant stiffness values and increase the damping value will reduce the torsion vibration peak of drive line,but excessive increased of damping value will influence the performance of torsional vibration in high speed range.At last,the improving direction of clutch was got by simulation analysis,and introduce the big angle of platen as improvement scheme,then validates the effectiveness of the measures by simulation and real vehicle test comparation,provides a certain reference value for the traditional clutch design.