Investigation on Meshing Stiffness, Load Distribution, and Dynamic Characteristics of a Three-Dimensional Compliance Gear-Hollow Shaft-Bearing System

Abstract

The design of hollow shafts is a common method in lightweight gear transmission systems, increasing the flexibility of the shaft. However, traditional models usually make the assumption of a rigid shaft or neglect the intricate effects of shaft flexibility on the contact characteristics of gear tooth pairs, which results in inconsistencies between model predictions and real-world observations. To settle this problem, a new three-dimensional analytical finite element model of a compliance gear-hollow shaft-bearing system is proposed. The proposed method considers the flexible effects of the hollow lightweight shaft, bearing, local contact between gear pairs, gear tooth, and the foundation. It enables the study of load distribution and time-varying meshing stiffness (TVMS) affected by hollow lightweight shafts. Based on the established dynamic model, the dynamic characteristics of the gear-hollow shaft-bearing system are analyzed. To validate the effectiveness of the proposed method, both the finite element method (FEM) and experimental methods are employed. Results demonstrate the correctness of the proposed method in evaluating the effect of hollow lightweight shafts on nonuniform load distribution, TVMS, and nonlinear dynamic characteristics. This evaluation yields better performance when compared to traditional methods that overlook the hollow lightweight shaft. It is inferred that this study can offer a theoretical basis for the design of hollow lightweight shafts in the gear transmission system.