Straight bevel gear is the main component of mechanical system. It has the characteristics of constant speed ratio, stable transmission and easy installation. It is often used in automobiles, machine tools and other mechanical power devices. In the meshing process of straight bevel gear, the teeth suddenly mesh in the tooth direction, which makes the system have impact, reduces the stability of the system, and causes vibration and noise. Therefore, exploring the transmission dynamic performance of spur bevel gear in differential plays a significant role in reducing vehicle vibration and improving the working efficiency of gear system.
At present, the main methods to reduce the vibration and noise generated by involute spur bevel gear transmission and improve the uneven distribution of tooth load are to improve the manufacturing accuracy of gear products, which greatly improves the requirements of manufacturing equipment and technology and greatly increases the production cost; Changing the gear structure, such as coating the gear surface, can improve the bearing capacity of the gear and reduce the system vibration and noise, but it will also increase the damping in the process of gear meshing; In addition, improving the lubrication mode and improving the installation and assembly quality can also reduce the vibration and noise to a certain extent, but the effect is not significant. At present, it has been proposed that the transmission performance of the gear system can be improved by reasonable tooth profile modification without increasing the production cost. Although these studies have achieved some results, there is no systematic theory on the influence of modification on the dynamic performance of gear transmission.
Based on the malleability of spur bevel gear structure, precision forging is one of the most common ways to manufacture spur bevel gear at present, but the precision of precision forging is not high, and the gear will produce elastic deformation after being loaded, which is more likely to lead to serious impact vibration and stress concentration during transmission, The tooth profile modification of bevel gear is an effective way to improve its transmission accuracy. Tooth profile modification is a key technology of great and far-reaching significance to improve the comprehensive working performance of gears. At present, many achievements have been made in the research of cylindrical gear modification technology, many tooth profile modification methods have been put forward, and a relatively systematic and complete modification theory has been formed. However, due to the particularity of bevel gear structure, the research on bevel gear modification technology is not very mature, especially the influence of modification on the dynamic meshing performance of bevel gear.
Some achievements have been made in the research of tooth modification technology. In view of these theoretical achievements, taking the automotive spur bevel gear as the research object, based on the formation principle of spatial spherical involute and gear dynamics theory, the accurate modeling of three-dimensional solid model of spur bevel gear before and after modification is completed by using SolidWorks software, and according to the established multi degree of freedom dynamic model of bevel gear, The dynamic simulation analysis model of straight bevel gear before and after modification is established, and the dynamic performance of bevel gear transmission before and after modification is analyzed according to different specific working conditions. Then, by comparing the vibration performance of bevel gear transmission system before and after modification, the influence law of different tooth shape modification parameters (modification length, modification amount and modification curve) on gear meshing performance can be summarized.
The research work has high guiding significance and practical value for improving the dynamic performance of spur bevel gear transmission, reducing the vibration and noise in the transmission process and obtaining good modification.