Dynamic Analysis Of Ultra-precision Machine Tools And Basic Vibration Isolation Technology Research Under The Action Of Environmental Micro-vibration

Ultra-precision machining technology is the supporting technology of modern high-end equipment manufacturing,and continuously improving the machining quality is the primary goal in this field.The main factors affecting machining quality are the dynamic characteristics of the ultra-precision processing machine tool and the micro vibration of the environment.This article mainly studies from the following aspects:(1)The computational fluid dynamics method is used to study the dynamic characteristics of air-static pressure spindle system.To solve the negative grid problem when the large-scale dynamic grid of the air static pressure spindle system is modeled,this paper based on the ANSYS? ICEM CFD ? software,combined with the multiblock method and structured grid method Establish the gas film grid model.The dynamic grid technique is used to analyze the influence of the inlet diameter,inlet pressure,gas film thickness,and rotation speed on the linear stiffness and angular stiffness of the air static pressure spindle system.(2)The effectiveness of the dynamic model is verified by comparing the dynamic characteristics of the machine tool obtained by numerical simulation with the modal test results.In addition,because there is a big difference when white noise is used as a power spectrum to simulate real-world micro-vibration,this paper measures the microvibration data on the outside of the machine tool foundation and generates environmental micro-vibration acceleration power spectrum density to simulate the environmental vibration excitation.Then studies the vibration response of the spindle under the environmental vibration excitation.The results shows that the spindle vibration response reach to 0.309?m.(3)The basic vibration isolation technology of ultra-precision machine tools is explored,which is a two-level vibration isolation scheme.The first level uses a mass concrete block including a damping material cushion,and the second level uses a piezoelectric stack actuator and an air spring.The strategy control is fuzzy PID adaptive control.The simulation results show that: compared with passive vibration isolation,the vibration isolation effect of this vibration isolation scheme is greatly improved,which vibration isolation rate actieve as high as 80%.