Design And Analysis Of Dynamic And Static Characteristics Of High-speed Motorized Spindle For Turning

High speed machining technology which based on the high speed cutting theory is a new creative technology that could meet the requirements of high precision,high speed and high efficiency in modern manufacturing field.Since twenty-first Century,with the rapid development of high speed machining technology,it plays a more and more important role in the field of modern manufacturing.High-speed motorized spindle is a symbol technology of high speed machining technology,and its capability determines the quality of the high speed machining machine tool.In order to ensure the manufacturing quality,it is very necessary to study the structure and the characteristics of dynamic and static of high-speed motorized spindle.Turning is one of the most widely used tools in the field of NC machine.In this paper,high-speed motorized spindle for turning is the research object.And the key parameters,the design of the overall structure,the dynamic and static characteristics of the motorized spindle are studied in the paper.The specific research contents are as follows:First of all,the paper determines the index parameters of spindle according to the market research and designs development route according to the index parameter.Meanwhile,the paper designs the spindle which includes the design of motor,bearing selection,configuration,preload and lubrication,cooling system design,dynamic balance design,etc.And all of the design is based on the overall layout of the system.In addition,the paper designs and checks the key parameters,such as the design of the shaft diameter,span and motor interference.Secondly,in order to verify the rationality of the structural design,the static stiffness of the theoretical calculation and finite element analysis are completed.At the same time,the relationship between the bearing preload and the static stiffness of the main shaft is also explored.Besides,the dynamic characteristics of high-speed motorized spindle are analyzed by ANSYS.The natural frequencies and modes of the first six orders are obtained by the modal analysis.Then the corresponding critical speed is calculated.And the response displacement with frequency variation curve through Harmonic response analysis is got.For verifying the rationality of the design,the paper analyzes the response displacement of the key parts of the motorized spindle and it is concluded that resonance will not occur in the spindle speed range.Meanwhile,it puts forward some measures to improve the dynamic characteristics according to the results of the analysis.Finally,the spindle components are assembled based on the theoretical design of turning high-speed motorized spindle.The paper builds the testing platform for the spindle.Then,some tests analyses of high-speed motorized spindle are carried out by using the existing experimental equipment to further verify the rationality of the design of the spindle.The tests are composed of the static stiffness,rotation precision,the effect of the cooling system and so on.Therefore,the rationality of the design is verified,which provides a reference for the optimization design of the motorized spindle and the following tests.