| Gear transmission is the most widely used transmission form in all kinds of equipment,its system’s dynamics behavior and vibration characteristics directly impact on the overall performance and reliability of processing of mechanical equipment.However,gear transmission system the influence of the time-varying parameter is essentially a multi degree of freedom nonlinear system for the influence of the time-varying parameter,the nonlinear vibration mechanism of the complex gear transmission system is not yet clear;at the same time the existence of the gear backlash also seriously affected the transmission accuracy.Therefore with respect to the researches of the nonlinear dynamic characteristics of gear transmission system,to guarantee the precision of the transmission system response and safe operation of all has the vital significance.Based on the backlash of gear transmission stability strongly affected,this paper presents a double worm gear and worm precision transmission system,in the workbench the realization of the aim of eliminate backlash,precise transmission,and combined with the gear dynamics,nonlinear vibration,the finite element analysis and other theories and methods,to make a study on nonlinear dynamics features of precision transmission system.The main researches work is as follows:First of all,according to the application background,the structure characteristics to introduce double worm gear and worm of precision transmission system in detail,and according to its own eliminating the backlash principle to launch comprehensive description to offer designing a new type of anti-backlash institutions research idea and reference value;At the same time,explain the causes leading to vibration analysis of gear transmission system and the influence mechanism of research direction for the subsequent dynamic analysis.Second,by using ANSYS software,and the dynamic modal analysis,getting the double worm gear and worm anti-backlash mechanism with the intrinsic characteristics of the corresponding vertical workbench for reference;Further comparative analysis of both-natural frequency and vibration mode,the discussion of draw resonance frequency,lay a foundation for the research of nonlinear vibration.And then,Under the assumption of certain prerequisite conditions,application concentrate quality standard established dynamic model of double worm gear and worm anti-backlash mechanism,list the nonlinear dynamic equation system,by further simplifying operation,parameter setting and dimensionless equations,derive the differential equation of nonlinear analysis of the system,for the similar model of gear transmission system equations are set up to provide the reference;according to the transmission system of general condition,uses the method of numerical integration in the MATLAB simulation to obtain the time course of the system diagram,phase diagram and the spectrum diagram,provide a theoretical basis to confirm its nonlinear dynamic performance;further selected meshing damping and time-varying meshing stiffness as the research object,by comparing the dynamic response under different numerical change,to analyze the influence of specific laws,provide valuable reference for the parameter optimization of the gear transmission system.The last,based on LS-DYNA gears dynamic contact simulation analysis,completed the construction of gear pair geometry analysis model;and introduces in detail the matters needing attention in the process of pretreatment and analysis,to solve the simulation to obtain the gear tooth surface dynamic contact stress nephogram,mesh point contact stress and tooth root the time course of the effective stress diagrams,analysis of the reasons set forth sharp fluctuations tooth contact force and the root of effective stress,the maximum stress values obtained data may provide a basis for gear fatigue life estimation.This paper response the double-precision worm gear drive system as the study object,with its nonlinear dynamic response as the research focus,set up the nonlinear dynamic model of the transmission system and to solve;the conclusion of the study to determine the double-precision worm gear drive system dynamic response characteristics provide an important basis,at the same time to solve the problem of the optimization of gear transmission system stability has a specific reference value. |
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