Dynamic Analysis Of Non-circular Gear Motors

Non-circular gear has the characteristics of smooth transmission,compact structure,as well as achieve the motion equilibrium and regular variable motion easily.The application of non-circular gear on the hydraulic motor can equip the motor with advantages of small volume,large displacement,oil proof and others.But because of the constant change of non-circular gear's pressure angle,engaging force and central distance,it's hard to conduct the kinetic study.The previous research is only limited to non-circular gear with two external meshing.The paper puts forward the higher-order elliptic gear on the basis of balance the radical force and increases motor displacement,and carries on the research concerning the vibration characteristics of the elliptic planetary system.First of all,in this paper,the structure of elliptic planetary gear system,meshing principles of gear and the motion relationship of gear train are studied.The paper adopts the numerical analysis method to deduce the curvilinear equation of sun wheel and annular gear,and the way to draw other gears' pitch curve by using the cubic spline interpolation by knowing curvilinear equation in the gear train.Also,the paper develops the interactive interface to parametric design of the elliptic planetary gear structure,so as to achieve the function that obtain different elliptic gear pitch curve by simply inputting relevant parameters.Secondly,the paper establishes the torsional vibration mechanical model in the system based on the dynamic performance of elliptic gear system and theory of service life,and studies the exciting vibration factors in the model,such as the shape and structure of the gear,the output speed of the sun rotor,the time-varying stiffness,the overall error and the gear pair gap.Thirdly,the paper uses the displacement on the mesh line as independent variable to deduce specific oscillatory differential equation of elliptic gear,and solve the equation by using high accuracy Runge-Kutta method.It takes 6-8 orders elliptic planetary gear system as an example,uses the method of linear approximation method to analysis the time-domain response,phase diagram,frequency spectrum,etc,and researches the dynamic response of the system,further analyzes the influence of damping and revolving speed on dynamic response.Finally,in regard to the characteristics of non-circular gears,the paper accomplishes the machining simulation,code generation and transmission of non-circular gears by using the wire cutting simulation software,and finally implements the machining.The paper applies the interpolation method and parameter of section curves in the GUI interface to simplify the design process of elliptic gear.The established dynamics model and differential equation are applicable to all the planetary gear systems of variable central moment.In addition,the paper simplifies the machining process of non-circular gear by using wire cutting simulation software.The results of dynamic analysis in this paper provides a theoretical foundation for the vibration of non-circular gears,as well as the noise detection and vibration mitigation measures of non-circular gears.