The increasing diffusion of plastic gears in many industrial sectors makes it necessary to have a better knowledge of the bending strength properties of teeth in order to ensure an adequate design process. However, technological development has not gone hand in hand with the standard development necessary to carry out an optimized design process. To date, the specific standards for plastic gears refer mainly to design and calculation methods for the metal gears. So, the possible optimization strategy for the tooth root geometrical profile is also driven by the typical metal production processes. This paper presents an innovative approach, supported by an analytical procedure, to design optimized plastic gear wheels. The results obtained by the analytical approach is compared to the standardized one to highlight similarities and discrepancies. The goodness of the proposed results is verified also through finite element numerical analysis. The goal of the paper is to provide the designer with an analytical approach useful to optimize the root geometry design of plastic gears for lower root bending stress.

塑料齿轮在许多工业领域的日益普及使得有必要更好地了解齿的弯曲强度特性，以确保适当的设计过程。然而，技术发展并没有与执行优化设计过程所需的标准发展齐头并进。迄今为止，塑料齿轮的具体标准主要是指金属齿轮的设计和计算方法。因此，齿根几何轮廓的可能优化策略也由典型的金属生产工艺驱动。本文提出了一种创新方法，在分析程序的支持下，设计优化的塑料齿轮。将分析方法获得的结果与标准化方法进行比较，以突出相似性和差异。所提出的结果的优良性也通过有限元数值分析得到验证。本文的目标是为设计人员提供一种分析方法，用于优化塑料齿轮的齿根几何设计，以降低齿根弯曲应力。