Structural Strength Finite Element Analysis Of CVT Ball-Keyway

Along with the improvement of living, the amount of the vehicle is increasingyear by year. As a result, the environmental pollution and the energy crisis becomethe focus that being regarded by the whole world. The design of transmissiondirectly affects the AFE Automobile Fuel Economy, power performance and thegas emission. Because the Continuously Variable Transmission (CVT) can matchwith the engine best and can improve the AFE Automobile Fuel Economy, powerperformance. Metal V-belt CVT is regarded as the best structure, because of itsbrief makeup, easily manipulation and excellent performance. Metal V-belt CVT isdeveloping better and better, and has fine developing fore-ground and capaciousMarket Space.As the perfect transmission system, Metal V-belt CVT is applied more andmore. As the necessary structure of CVT to transfer force, the ball-Keyway'sperformance (such as: stiffness) affect the performance of the whole car. In order toensure the contact stress on ball-Keyway of the drive shaft and the driven shaft, thefollowing steps are done:1. On the basis of a great deal of reference literature home and abroad, theapplication on vehicle of Metal V-belt CVT are briefly expound, as well as thedevelopment and the foreground of CVT. Emphasize the principle of Metal V-beltCVT, the basic structure and the key components, further more detailedly expoundthe components and the structure of the aiming object (ball-Keyway).2. On the basis of the reference literature, basic concepts of FEA and the sortsof nonlinear issue (including material nonlinear, geometry nonlinear and thecontact nonlinear issues) are introduced. The difficulty of the contact nonlinearissue, the quest process and the quest means are the focuses being introduced.3. By simply the 3-dimension model of the ball-Keyway structure of the drive,driven shaft of the Metal V-belt CVT in UG, partition the 3-dimension model of thekey components utilizing Altair/Hypermesh, then introduce the element typeapplied to the discrete 3-dimension model and the criterion to control the elementquality. After importing the FEA model into ANSYS, constraint the model, applyboundary constraint, define material for the model and define the contact pair. Thenintroduce the contact element adopted detailedly. By now, the FEA model of theball-Keyway has been set up.4. By reason of the difficulty to certain the load on the steel-ball when thedrive, driven shaft rotate, the paper simulate the variety of the steel-ball load whichvarying with the rotation of the shaft, and the curve of the load varying as aconclusion is presented. Besides calculating the contact stress and the stressdistributing of each contact pair of the ball-Keyway, the comparison and analysis ofthe results are carried through. As the results indicate ,the following conclusion aregot: (1) for either keyway of the drive, driven shaft, the contact stress on thesteel-ball near the conical wheel are greater than the contact stress on the steel-ballfar from the conical wheel. (2)Even under the fixed velocity ratio and torque, thecontact stress on either keyway is fluctuant periodically with the rotation of theshaft. (3) The greatest contact stress occurs on the driven shaft, during thetransmission process.At last, the factors that cause the results error are discussed and qualitativeanalyzed. The conclusion can provide reference for the Structural Optimization ofthe ball-Keyway of the drive, driven shaft of the CVT.