Mechanics Modeling And Stability Analysis Of Variable Section Scroll Milling

Because of the complex profile design,the milling process of the variable cross-section scroll plate,which is the core component of the scroll compressor,is more complicated and more difficult than that of the ordinary equal cross-section scroll plate.Whether the milling parameters are reasonable or not determines whether the variable cross-section scroll produced by milling meets the requirements of both quality and accuracy.From the point of view of milling stability,the following aspects are studied in order to obtain more efficient and stable milling parameters.(1)Firstly,according to the characteristics of different types of scroll profile,three segments of base circle involute are selected as the processing object of this variable cross-section scroll milling experiment,and its geometric model is established.Based on the instantaneous rigid force model,considering the profile characteristics of variable cross-section scroll plate,a milling force model suitable for variable cross-section scroll disc milling is established.(2)Design four factors and five levels of variable cross-section scroll milling test program,combined with experimental equipment conditions for actual milling,The dynamic milling force data collected from milling experiments are sorted out and the average milling force is calculated.The average milling force coefficient is obtained by means of the average milling force coefficient method.(3)Based on the vibration data of the milling experiments,the vibration response curve of the milling chatter system in the milling process is obtained by optimizing calculation of the data analysis software,and the relative static state in the concerned frequency band is calculated according to the curve.The modal parameters are closer to the actual processing process.(4)Using the classical spring oscillator model to simplify the variable cross-section scroll milling system,considering the regeneration effect,the differential equation of the variable cross-section scroll milling vibration is established,and the mathematical relationship between the axial shear depth and the spindle speed is deduced.(5)On the basis of milling chatter theory and milling parameters calculated previously,according to the process of lobe drawing,the stability lobe diagram of variable cross-section scroll disc milling process is drawn by means of MATLABprogramming,and then the high-efficiency and stable processing parameters are identified by the size of stable region by changing the specific parameters,so as to select more efficient and stable processing parameters for the actual milling process.Provides the reference basis.