This paper discusses the research status of tooth modification technology, gear transmission dynamics theory and gear transmission dynamics simulation analysis at home and abroad. Through the establishment of accurate three-dimensional solid model and mathematical analysis model of spur bevel gear, the dynamic analysis of spur bevel gear transmission before and after modification is carried out, The situation and degree of tooth profile modification improving the dynamic behavior and vibration characteristics of gear transmission are discussed. The dynamic performance of spur bevel gear transmission system before and after modification is studied.
The research content mainly includes the following parts:
- Introduce the background, purpose and significance of the research. This paper discusses the principle of gear transmission modification and the related theories of gear transmission dynamics, summarizes the research status of gear transmission modification technology, gear transmission dynamics simulation analysis and gear transmission dynamics theory at home and abroad, and gives the main research contents.
- Based on the formation principle of spherical involute, the accurate three-dimensional solid model of modified involute spur bevel gear is established by using MATLAB and SolidWorks software, and the detailed modeling process and the determination method of gear modification parameters are given. This method eliminates the error of the model established by other approximate methods, and improves the model accuracy and modeling efficiency, The accuracy of the following dynamic simulation results is guaranteed.
- The method of gear transmission dynamics simulation analysis is discussed, and the steps and results of gear transmission dynamics research using romax designer software are given. The three-dimensional solid model of spur bevel gear established by SolidWorks is imported into the dynamic analysis software RomaxDesigner in STL (*. STL) file, and the specific working conditions of the model are set for static analysis and dynamic analysis. Through static analysis, the strength, service life and safety factor of gear teeth in the transmission process are obtained. Through these results, we can see whether the system can operate safely and reliably, and ensuring the normal operation of the system is the prerequisite for the dynamic analysis of gear transmission system. During the dynamic analysis of gear transmission system, the transmission error excitation is used to obtain the dynamic response results of gear transmission system (dynamic contact load, linear modal flexibility) by using the NVH analysis module of the software.
- Based on the theory of gear transmission dynamics, the vibration model of multi degree of freedom spur bevel gear pair is established. This model ignores the influence of the elastic deformation of box and support on the dynamic behavior of the system. In addition, the dynamic equation of straight bevel gear is listed according to the model, and the nonlinear parameters (time-varying meshing stiffness and tooth side clearance) in the dynamic equation are determined, and then the dynamic equation of bevel gear is simplified and solved. The establishment of bevel gear vibration model is not only the basic condition of gear transmission dynamic simulation analysis, but also conducive to the correct establishment of dynamic simulation model.
- According to the established torsional vibration model of bevel gear, the dynamic simulation model is established in RomaxDesigner, and the transmission error of straight bevel gear before and after modification is analyzed. Taking the transmission error as the excitation, the natural characteristics and vibration response curve of modified straight bevel gear transmission are obtained. By comparing the dynamic performance of straight bevel gear before and after modification, The influence law of tooth profile modification on the dynamic performance of gear transmission system is summarized to guide tooth profile modification and obtain better modification effect. In addition, this chapter discusses the basic problems of gear transmission dynamics (gear excitation type, dynamic characteristics, dynamic performance index).