A Study on Design Optimization of Spur Gear Set

In this article, a profile modification approach is adopted for the design of a spur gear set to minimize the contact stress and optimize the weight. An altered tooth sum method is used to reduce the hertizian contact stress along the path of contact. Four case studies are performed for the spur gear set with specific center distance and tooth sum of 90 (±5). A multi-objective optimization problem is formulated with contact stresses along path of contact and weight of gear set as the design objectives. This nonlinear-constrained optimization problem has been addressed by mean of the particle swarm optimization algorithm. Six design variables related to gear geometry and material property are used in this optimization and all the imposed constraints are satisfied at the optimal solution. Gear and pinion surface temperatures are below flash temperature, indicating protection against scoring wear. Specifically, a lighter gear with less contact stress and adequate scoring resistance is reported in this study. Furthermore, a CAD model is developed by means of optimized design parameters so as to check the geometric interference and practical feasibility of the design.