| With the development of mechanical engineering, Equip and make, Petrochemical industry , Communications and transportation , Aero-Space and war industry of. national defence ,etc, such requisitions for high speed and high-accuracy machining center improve notably. And the dynamic characteristic is one of the most important indexes of machining centers. So, to improve the dynamic performance is significant.In order to guarantee the lathe has good moving rigidity , dynamic characteristic , precision keeping and processing technology quietly , need to carry on systematic dynamics analysis to the lathe during the process of designing and making the lathe, in order to can accurate discovery limit lathe dynamic weak link that performance raise rapidly, realize designing dynamically fast, in a flexible way, offer the basis with rational science for structural design of the lathe.It is the relative motion between cutter and work-piece that the processing course of the machining center. Work piece —The cutter makes up an elastic system, in fact is equivalent to the work piece —knife towers (the associations of the post and knife rest) makes up an elastic system. We know from forming process to process part if machining center cutter and work piece make the relative motion along ordered orbit, can get the ideal work piece outline form ; Otherwise difficult to get satisfy demand. The knife towers, as one of the elements of the elastic system, it influence part surface take shape accuracy , sport of orbit directly, so its quiet dynamic performance will influence the productivity of the machining accuracy , surface quality and lathe of the part directly. So study the dynamic characteristic of the knife towers and raise its ruggedized and stability is essential.There are several problems to be resolved on terms that studying about the stabilities and ruggedized of the knife towers.First, the quietly rigidity of the knife towers, namely on terms that meet the precision of limit, its structure shape is in the range permitting.Second, carry on dynamic analysis, such problems as the natural frequency, responding to the structure humorously ,etc.Third, on terms that meet demand of processing, optimize its structure.This paper adopts the way of dynamic design and carry through dynamics analysis above three respects and simulation on the structure system, predict and analysis the dynamic performance and modal characteristics of the structure, and improve them.This paper bases on theoretic analysis, the finite element analysis and kinetic simulation, and get out of its true dynamics characteristic, limit deformation picture of terms and ocular judges its deformation amount. Ask out the six stepses of modes,shake shape and natural frequency. And offered the theoretic basis and solution for achieving the design goal. The results are of denotation and practical value. |