Performance And Structural Design Of Interchangeable Taper Sleeve High Speed Spindle/Shank Interface

The coupling performance of the spindle/shank of a high-speed machine tool directly affects machining accuracy and spindle end life.At high rotational speeds,the centrifugal expansion caused by the inner bore of the spindle causes the coupling stiffness of the spindle/holder to decrease and shift.The positioning accuracy of the tool is reduced;frequent tool change accelerates the wear of the spindle end.In view of the above problems,this paper proposes a new type of interchangeable taper sleeve high-speed spindle / tool holder interface structure,referred to as the new interface,and analyzes the performance of the new interface and structural design.The specific research content is as follows;Firstly,the geometric model of the structure of the new interface was constructed with the HSK tool holder interface standard,and the main structural parameters were determined.The design requirements and performance indicators of the new interface were determined.Secondly,under the premise of ensuring the joint stiffness of the combined spindle structure,the pre-tightening force of the screw is determined and the type of the screw is selected;under the premise of ensuring the positioning accuracy of the combined spindle structure,the interference of the positioning side of the new interface is determined;The finite element software analyzes the relationship between the contact stress of the taper and the end face of the shank as a function of the rotational speed,and optimizes the dimensional parameters of the interface by designing orthogonal tests.The finite element software is used to analyze the contact state of the shank cone and determine The interference of the shank gives the dimension of the spindle body,the front end of the spindle and the shank.Finally,the connection performance of the new interface is analyzed.The positioning accuracy of the new interface is analyzed.The radial stiffness and torsional stiffness of the new interface and HSK toolholder interface are compared and analyzed by finite element software.Under the premise of processing,the pre-tightening force of the rivet is determined;the average contact stress of the taper and the end face of the shank is calculated by the finite element software,and the limit rotation speed of the shank is determined.