Papers by Keyword: Tooth Root Stress

Abstract: Gear offsets mesh in axial misalignment always leads to unevenness of load transferred contributing the impact of stress value and distribution along important critical path of the tooth root. Its happening due to overpress fitting when the gear is mounted onto the shaft as an interference hub fit. Current design methodology based on empirical model provide solution by approximation load factor fail to attributes in detailed regarding this phenomenon This paper determined to focus on this phenomenon in term of methodology to the stress distribution at the critical contact region of the tooth root of the gears. Pair of spur gear with real geometrical construction and condition was constructed with offset parameter. A moving load quasi-static model with a numerical FEM solution using ANSYS is presented with modification in loading variation. For verification, the stress value at the critical path of the tooth root is compared between standard high point single tooth contacts (HPSTC) loading to moving load model. As the result, a numerical FEM methodology to calculate the stress distribution of the gear tooth root in offset axial misalignment with moving load model approach is determined. The proposed method is also found reliable as an alternative solution to define an accurate load factor calculation compared to the approximation provided by the standard empirical procedure.

Abstract: The paper deals with the discussion how nominal spur tooth root stress of thin-rimmed gear determined in accordance with the standard ISO 6336-3:2006, method B, agrees with the results of the 3D FEM stress analysis. The procedure proposed by standard ISO for the tooth root stress calculation doesn’t identify the stress behaviour related to mutual affects of characteristic thin-rimmed gear geometrical parameters. Therefore, the 3D FEM analysis of tooth root stress has been performed for gear structures with middle and offset web with various rim and web thickness. The rim thickness has covered and slightly overcome the backup ratio defined by ISO procedure, while the web thickness has covered the range of practical interest.

Abstract: The paper presents a study on the tooth root, rim and web stresses of thin-rimmed spur gear structure with symmetrical web, based upon 3D FEM calculations. In order to identify some gear design directions, the effects of rim and web thickness on gear stress behaviour are investigated, and maximum stresses resulting from actual rim and web contribution are compared.