Structure Analysis And Improvement On Housing Of Metal V-belt Continuously Variable Transmission

Metal belt type continuously variable transmission (CVT) can realizecontinuously variable ratio in a wide range so that the vehicle can obtain the bestmatching between the driving system and engine，and achieve improvement of vehiclefuel economy. CVT housing supports the entire transmission system operation, whosereliability must be guaranteed. As we all know, strength, stiffness and vibrationcharacteristics directly all affect the reliability of CVT. Thus, it is very important toanalyze its strength, stiffness and modal.In this paper, the basis structure and working principle of CVT is illustrated.Thus the force between driving-driven pulleys and shafts, as well as load of bearings,is obtained, which provided the theory for further study. Secondly, A set of tensile testbench is designed according to the CVT front housing suspension structure and iscarried out tests for the original front housing suspension structure, and suspensionstructure is also analyzed based on finite element method (FEM) in the sameexperimental conditions. After that, comparing with the test data, the result of FEM isto a certain extent proved to be effective. And the suspension structure is improved onthe basis of FEM result. Both the FEM and the experimental results prove that theimprovement is very effective. Furthermore, mainly considering the bearing loadconditions, the present CVT housing is used to do the strength and stiffness finiteelement analysis. And the eight bearing housing inner surface deformation and stresschanges rule is obtained in different ratio. Further analysis on the coaxial degree dueto the influence of deformation is practiced, and the improvement of the housingwhere it is relatively weak is raised. Via the FEM analysis, the improvingmeasurement of housing is reasonable and effective. Finally, the modal analysis forthe CVT housing is achieved, thus the front ten natural frequencies and vibrationmode are obtained, which provide direct theoretical basis to housing structure design.These results provide significant references for the study of CVT housing crack andfracture, optimization design, and how to further improve the transmission efficiencyand expending lifespan of CVT.