The Basic Common Technology Research On Numerical Control Machine Tool Clamping System

The rapid development of NC machine puts forward more strict requirements to cutting tool system continuously.The clamping system,as the important connection part of NC machine spindle and toolholder,affects the reliability of the connection,has serious influences on machining quality,efficiency and tool life.It has a great important value for developing high-performance NC machine toolholder clamping system independently and ensuring the safety of machine to study the basic common technology research on NC Machine tool clamping system,analyse the clamping force generation,amplification and transmission process and the effects of clamping system on tool system performance.This paper,on the basis of theoretical analysis,studies the characteristic of NC machine toolholder clamping system by combining the finite element numerical simulation with experiment.This paper analyses the basic characteristic of clamping mechanism and its effect on the performance of tool system.Then,an end face clamping force measurement method is put forward.Main work and research results of this paper are as follows:(1)This paper analyses the characteristics of typical toolholder clamping system.The force generation and transmission mode of clamping mechanism is studied as well.This paper analyses the clamping force amplification method and identifies the magnification.It is demonstrated that the outside up type clamping mechanism is more suitable for high speed cutting.(2)Based on the contact analysis method,established the contact analysis model of different tool system,analyzed the influence of contact clearance,contact stress of BT and HSK toolholder by the clamping force.Get the influence of the clamping force on end face contact stress,taper contact gap,the maximum contact stress and the non-contact area.It is of great value to control a reasonable clamping force.(3)Research the influence of tool system performance by the clamping system structure and the clamping force.Researches shoes that tool system with end face positioning have more outstanding performance.Get the influence of the clampingforce on tool system coupling stiffness and tool system ultimate load.It is of great necessity to choose the appropriate clamping system and reasonable clamping force to guarantee tool system excellent connection performance.(4)From the perspective of HSK toolholder clamping force magnification,this paper determines the force control method,points out that the biggest influence factor is friction coefficient of the wedges surface and finds the optimal value range by analyzing.(5)Designed an end face clamping force measuring mechanism of HSK toolholder.By analyzing the working principle of overseas clamping force measurement,this paper put forward a kind of end face clamping force measuring mechanism of HSK toolholder,solving the problem of toolholder end face clamping force measurement,providing technical support for the safety of high-speed machining.