Natural characteristics analysis and experimental test of spiral bevel gear pair in the tractor transmission system

Yuan Chen,Xudong Mou

doi:10.1177/16878140211037120

Abstract

Spiral bevel gear is widely used in various mechanical transmission systems, such as tractor transmission system. Because it is mainly used in the heavy-load conditions, it would most likely resonate within the rated speed, resulting in tooth fatigue damage. In this paper, based on the principle of meshing and gear tooth machining, the spherically involute tooth profile equation of spiral bevel gear is deduced and the precise modeling method based on the CATIA is studied. The natural frequency and modal shape under free vibration are obtained by the finite element method (FEM), the influence of web thickness and web hole on the natural frequency of driven gear plate is analyzed as well. In addition, the experimental modal of bevel gear pair is carried out based on a multiple-reference impact test, Modal Assurance Criterion (MAC) is calculated, the three-dimensional modeling accuracy and the finite element analysis reliability are verified. The results show that the error between the measured frequency of bevel gear pair and the calculated frequency of the finite element simulation are both within 5%, and the MAC is above 0.8. The fourth-order natural frequency is the most sensitive to the web thickness, the second-order natural frequency is the most sensitive to the web hole.

Highlights

Spiral bevel gear occupies several strong points like good carrying capacity, and it is widely used in aerospace engineering, precision machine tools, and other modern mechanical transmission fields
It can be seen from the table that the first order is 3423.5 Hz, and the error between the test frequency and the finite element method (FEM) simulation frequency is less than 5%, the Modal Assurance Criterion (MAC) values are all greater than 0.83, so the correlation between the modal shape is very high
The natural characteristics of spiral bevel gear depends on the structural parameters, and have a low impact on the operating conditions, so the change of web structure will have a great impact on the natural frequency and mode

Summary

Introduction

Spiral bevel gear occupies several strong points like good carrying capacity, and it is widely used in aerospace engineering, precision machine tools, and other modern mechanical transmission fields. An analysis of vibration characteristics of a spiral bevel gear is made with the purpose of finding out the weakness and avoiding resonance failure, thereby improving the service life of spiral bevel gear. It has an important research significance and application value for the spiral bevel gear structural design. In his spiral bevel gear modeling, Litvin et al.[1,2] replaced nonconjugate tooth surfaces for conjugated tooth surfaces in spiral bevel gears, and the conjugated surfaces were generated by two conical surfaces. Shi et al.[6] derived the tooth profile equation of noncircular bevel gear according to the generation

Objectives

Findings

Conclusion