| With the distinctive structures and the mechanical chemical、thermal,diamond has a wide range of application in many fields of science and technology.Especially,in the field of ultra-precision machining,the diamond is considered the best ideal cutting tool material.In the grinding process and the changing impacts mainly are from the vibration of grinding machine,these interferences will make relative motion between the lapped diamond tools and grinding disc.So diamond tools can not achieve the required processing precision,controlling of such vibration is very difficult because it itself has brought great force wave propagation in the processing of diamond grinding,if we only improve the accuracy of precision machine tool and inhibitory effects of the vibration,the deep complexity of the equipment and the cost of the equipment will very high.In order to reduce the influence of vibration,this paper invent the flexible floating diamond grinding device,this device introduced the elastic beam and the elastic cushion,the rigid systems will be replaced by a rigid-flexible coupling system thought the elastic beam and the elastic cushion,which strengthened the damping effect of elastic system and consumed much vibration and eliminate the influence the vibration and impact produce to surface quality of diamond grinding.But the process parameters will change,the contact load between the diamond and grinding disk also will change by the influence of the grinding speed and pressure,the installation error and the flatness error because of the elastic cushion deformation produce the jump of the diamond.So this paper main research the influence factors of the vibration in the grinding process through the experiment and simulation.Started from the diamond grinding mechanism,firstly,establish the two dimensional coupling system and analyses the vibration of the diamond surface,then introduces briefly the influence factors of the vibration in the grinding process.In order to measure acceleration,this paper set up the experimental platform of diamond experiment and signal acquisition equipment,studied the different stiffness,different load,different rotational speeds to the influences of the diamond vibration and use orthogonal experimental design to analyzes the three factors and the relationship between them. Secondly,it introduces the relationship between the contact load and the diamond vibration,and is reflected by the stiffness K3of the two-dimensional coupling system,then establish the contact stiffness K3with the the non-damped case and the damped case.Calculate each parameter value of the single freedom degree system through experiment,such as K1K2C1C2,Then combined the experiment with Matlab/Simulink,it calculates contact stiffness K3and measures its values while tested by using theoretic conclusion,the impact of the contact pressure and the elastic beam on the contact load.Finally,Analyze the influence of the relative acceleration on the contact load,then it use the change of the contact stiffness to response the vibration and impact to surface quality of diamond grinding by the experiment.The elastic floating grinding machine is established through the physical screen model established by the using of Pro/E and imported Multi-body dynamics to software ADAMS and define the parameters of the attribute information、constraint、drive、the contact parameters of the model.The finite element model neutral files of the elastic beam and the elastic cushion are generated by the Auto/Flex module function,then construct the rigid-flexible coupling model and verify through experiment.The displacement of the diamond directly affects the grinding quality,the effect of the length of the rotational speeds,the jump of the grinding disk and the irregularity of grinding plate on the displacement of the diamond is obtained by dynamics simulations.Finally it use the change of the displace to response the vibration and impact to surface quality of diamond grinding by the experiment. |
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