| Double Circular Arc Helical Gear has a strong contact bearing capacity, smooth transmission, easy processing and many other advantages, has been widely used in mining, metallurgy and other areas of the heavy-loading. The contact characteristics of Double Circular Arc Helical gearing was a very complicated process. The contact state of gear has great influence on meshing and dynamic performance, so the research on meshing relationship and contact performance of Double Circular Arc Helical Gear has both theoretical significance and practical value.In this dissertation, the contact characteristics of the Double Circular Arc Helical gearing are studied by using the GB12759-1991 Double Circular Arc Helical gear as the research object. Based on the meshing theory of the circular arc gear, differential geometry and elastic mechanics, combined with the geometrical characteristics and meshing characteristics of Double Circular Arc Helical Gear, and by using Pro/E, ANSYS, MATLAB and ADAMS carried on the analysis and simulation calculation From static mechanics, dynamics and gradually in-depth study.Paper’s main work includes:(1) The tooth surface equation of double circular arc cylindrical gears is derived. This paper described the characteristics of the double circular cylindrical gear meshing, and the meshing stiffness, contact stress was calculated. According to the tooth surface equation in Pro/E, wrote modeling program, and the modeling of the Double Circular Arc Helical Gear is accomplished.(2) Under static analysis module of ANSYS/Workbench, The author has carried on the research of Double Circular Arc Helical gearing along a line contact. By analysis the law of contact deformation and the influence of the radius difference of concave convex tooth on the contact stress, the value range of the radius difference of concave convex tooth under the contact stress was obtained. When the same load is applied to the contact point in the theoretical, studied of the variation of cloud contact stress, come with helix angle increases, the contact area from approximately elliptical, and gradually to approximate banana-shaped change, when the helix angle is further increased, the contact area expanded into approximately whale shape.(3) Based on the theory of multi-body dynamics, using ADAMS software to build the virtual prototype model of Double Circular Arc Helical gear meshing,to analyze the state of contact Double Circular Arc Helical gear in the process, we finally obtained the meshing force curve change over time curve, the driven wheel angular velocity curve change over time curve and spectral curve change over time curve. Also, We established a rigid--soft combination of Double Circular Arc Helical gearing calculation model based on dynamic contact analysis LS-DYNA explicit dynamic program to simulate the actual gear meshing, stress cloud listed under different meshing point, and for comparison with the static analysis, get the regularity of Double Circular Arc Helical gear meshing transmission, the simulation results intuitively clear.(4) Based on the theoretical analysis of the stress field method and fatigue, combined with the finite element method using ANSYS fatigue analysis module, we got Double Circular Arc Helical gear life under different stress levels. In this paper, the contact fatigue results provide a reliable basis for gear strength and prolong gear fatigue life.
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