Study On Complete Machine Dynamical Analysis Of Ultra-high Speed Grinder And Experiment

As ultra-high speed grinder is developed in high speed, high accuracy and high efficiency direction, dynamic characteristic of high-speed grinder has been becoming increasingly demanding. Dynamic design method is needed to upgrade the competitive power of ultra-high speed grinder. Accurate dynamic model is the foundation of dynamic analysis and dynamic design of ultra-high speed grinder, while the key factor of establishing an accurate dynamic model of ultra-high speed grinder is the treatment of the joint.The dynamic characteristic of ultra-high speed grinder has great influence on the dynamic characteristic of the machine tool.Ultra-high speed grinder and joint are research objects in this paper. Influence of the joint on dynamic characteristic of machine tool is analyzed using both theory and test method, then structural improvement and optimization on the main components of the machine tool is also made.The main contents of this paper are as following:(1) Ultra-high speed grinding technology, ultra-high grinder, research methods and status on guide joint are summarized. Research method combined with theoretical research, dynamic test and finite element analysis is proposed. Formulation of ultra-high speed grinding force is introducted. Grinding force and unbalanced inertia force in ultra-high speed grinding process is elaborated. The complete machine static analysis of ultra-high speed grinder is completed.(2) Establish the dynamic model of the joint of the ultra-high speed grinder. Dynamic characteristic parameters of joint are calculated used by Yoshimura method. Modal analysis of FEM of ultra-high speed grinder is made. Natural frequencies and corresponding mode shapes are obtained. Calculation of harmonic response analysis of FEM is made. Weak links of dynamic characteristics are found by analyzing.(3) Dynamic test is made on prototype of the ultra-high speed grinder. The first22-order natural frequency and its parameters of each modal are obtained. Rationality of FEM of ultra-high speed grinder is verified. Meanwhile; great influence of joint on the dynamic characteristic of machine tool is also verified.(4) Static and dyanmic analysis on the machine tool bed and column of ultra-high speed grinder is made. Weak links of these components are found. Influence of bed and column on the trends of dynamic characteristics is examined. Direction of improvement of bed and column is cleared. Structural improvement and optimization on these components are made to furthermore improve the characteristic of ultra-high speed grinder.