Gear Stress And Deformation In The Accurate Analysis Of Finite Element Modeling Study

On the basis of analysis of gear teeth strength, gear power capacity rating and profile correction, as well as vibration and noise of gearing, are studied. In view of accurate model, it is significant to investigate the deflection and stresses of engaging teeth precisely.On root stresses and teeth compliance, the advances in different calculi commented comparatively, then applied prospect of Finite Element Method (FEM) in the field is emphasized. Some principal techniques of accurately modeling in FEM for gear failures are developed systematically. Chief studies are conducted as follows. According to fundamentals of engagement of tooth profiles, exact equations of meshing teeth profiles are derived. Geometrical model of gear teeth with complex boundary is posed, by which compound modeling with APDL and MATLAB , based on full-text data file. The studies in view of the whole gear show the theoretical limitations of "expanding" initial boundary. The new "effective boundary", determined by equivalent stresses and deflection , is proposed. Criterion of loading position, including effective machining error and integrated compliance of gear teeth, is presented. Taking into account comprehensive stiffness, load sharing ratio of the central tooth in a meshing cycle , is calculated. Judgment of plane elasticity issues how to choose, in FEM analysis of spur gear strength, is put forward.According to the above studies, the distributing rules of root stresses and teeth compliance are investigated comparatively, and the results testifying the reliability of the model. Notable influence of hob tip radii to root stresses and teeth compliance proved, empirical formula proposed by Filiz should be corrected. Then including the affection of "superimposed stress when two teeth gearing", load-history of root stresses and teeth compliance of central tooth is researched relatively.Based on the numerical solution of teeth compliance by load -history analysis, and considering the error and distortion of gear teeth, the standard of the point situated at corner contact is probed and the impact forces, from the point situated at corner contact to theoretical lineHIof action, are calculated accurately. After viscoelastic oblique impact model founded, the formula of lash friction coefficient is deduced. The studies of other researches interpreted and inducted, three friction models in factual mesh period, including corner contact, are proposed, then the calculi of friction coefficient corresponding each model.