Research On Dynamic Pressure Assisted Small Tool Polishing Technology

With the increasing demand of optical components,new polishing technology based on traditional small grinding head polishing technology has been put forward,and the means for polishing optical components are more and more abundant.However,in order to obtain optical elements with higher surface quality,a single polishing method is still difficult to meet the actual needs,which often requires a variety of polishing methods to assist each other.Therefore,it is of great significance to explore and study the composite polishing method and process.Based on the traditional polishing technology of small grinding head and the principle of hydrodynamic pressure,this paper puts forward the hydrodynamic pressure assisted polishing technology of small grinding head,and makes a tentative exploration and Research on this technology.Firstly,based on Preston equation,the removal function characteristics of traditional small grinding head in horizontal rotation and planetary motion mode are analyzed,and on this basis,the removal function model of ring polishing head in horizontal rotation and planetary motion mode used in dynamic pressure assisted small grinding head polishing is established,and the influence of eccentricity and central aperture size of polishing head on the removal function profile is discussed in detail.The theoretical basis of parameter selection is provided for the structural design of subsequent polishing device and polishing head.Then,the flow field model of polishing area is established.The pressure field and velocity field in the flow field are analyzed by fluent.The pressure and velocity distribution of the fluid in the polishing area are obtained.Finally,based on the numerical analysis results and the hypothesis of Preston equation,the removal function model of the dynamic pressure assisted polishing of small grinding head is obtained.After that,the structure design of planetary moving polishing device and polishing tool head is completed.Based on the finite element analysis theory,the static analysis and the modal analysis of the whole supporting structure are carried out for each main part of the polishing device,and the optimization of the original structure is completed based on the analysis results.At the same time,the calculation and selection of key parts of polishing device and the design of control scheme are completed.Finally,in order to realize the automatic control of polishing system,the process control software of polishing system is developed based on C # language.On this basis,the polishing experimental platform was built,and the effect of process parameters such as grinding head down pressure,speed ratio and eccentricity on the surface roughness of the workpiece after polishing was explored.The experimental results show that the material removal efficiency of dynamic pressure assisted small grinding head polishing is better than that of traditional peripheral fluid feeding polishing.