The determination of tooth bending strength is a basic issue in gear design. This work presents the change of nominal tooth root stress of external toothed, cylindrical gears depending on the geometry used. The nominal tooth root stress is analyzed with using finite element simulations. The numerical calculations are executed in Abaqus. The imported geometries are produced by our own program in MATLAB. The boundary conditions to the models are defined accordance with the most significant analytical methods used in practice. This approach allows mapping direct correlation analysis by these calculations. The optimization of computational capacity used is also considered. In addition to the examination of the significant tooth stress value of symmetrical element pairs, the position of the critical cross-section is also analyzed. The effect of the asymmetric design of the tooth profile on the nominal tooth root stress is also presented in our investigations. The purpose of the numerical simulations carried out here is to determine the effect of the coast side angle on the magnitude of the significant tooth root stress and the position of the critical cross-section.

The calculation of mesh stiffness with required accuracy is essential for determining the contact characteristics of gear pairs. The easiest approximation of the relative stiffness for the basic profile geometries is the so-called single stiffness. Standardized and analytical methods for the determination of the single and mesh stiffness of gears are used to achieve design goals considering the load capacity and the vibration excitation characteristics. Such methods involve the formulas of ISO 6336-1:2006 based on experimental relationships and the equations of Weber and Banaschek based on mechanical calculations. In this paper, guidelines are given to refine the analytical calculations. Our goal is to present the impact of the change of the applied pressure angle, module, load, rim thickness and tooth number on the maximal single stiffness. The profile geometry of the gears is generated with our program in MATLAB. The profile of gears is calculated by the tool geometry and the kinematics of production. The geometry is imported into Abaqus. The sensitivity of the models to different parameters is examined and compared to those obtained by analytical calculations. The benchmarks for the single stiffness are the two most widely used analytical calculation methods in Europe such as ISO 6336-1:2006 formulas and Weber and Banaschek equations.

The present work deals with the geometry dependence of the nominal tooth root stress of external toothed, cylindrical gears. The profile geometries required to perform the calculations are derived by our own program in MATLAB. Finite element simulations are executed in Abaqus. When designing the models, the geometric constraints of each tooth crown were optimized, keeping in mind the accuracy of the simulation. In addition to the analysis of the significant tooth stress value of symmetrical element pairs, special emphasis is placed on the development of the position of the critical cross-section. The numerical results obtained are also compared with the most significant standardized methods used in practice. The effect of the asymmetric design of the tooth profile on the nominal tooth root stress is reviewed in our investigations. The purpose of the numerical simulations carried out here is to determine the effect of the coast side angle on the dominant tooth root stress. In the evaluation of the results, the location of the critical cross-section, in addition to the magnitude of the stress, is also considered.