The Research On Structure And Static & Dynamic Characteristics Of Electric Spindle Unit

High speed machining technology brought a far-reaching technological revolution to the machinery manufacturing, achieved significant economic benefits in actual production. The developing and application of high-speed machining technology must have excellent high-speed CNC machine tools, and high-speed motorized spindle unit to a large extent determines the high-speed machine tool performance, Thus there are great value and significance to study the structure of the high-speed motorized spindle unit, the static and dynamic performances which direct effects on the Machining accuracy and machining quality.In this paper, the key technology(bearings, lubrication, dynamic balancing, interference fit) of the high-speed spindle unit structure are studied with theoretical analysis and calculation combine with the electric spindle for turning, testing and verifiing the spindle unit structure design is reasonable; Analysing the rotation accuracy of spindle unit from the spindle, bearings, assembly process and so on. The directed assembly process is studyed and the method to get higher rotation accuracy is proposed;The rigidity of the spindle unit is analysed with theoretical calculation and finite element analysis, verifing the established three-dimensional finite element model of the spindle unit is rationality, analysing the specific measures to improve the stiffness of the spindle unit; The transfer matrix method and the finite element method are introduced in detail, and the finite element software ANSYS is regarded as the core method to analysis the dynamic characteristics of spindle unit by comparing two methods. The low natural frequencies and corresponding mode shape of the motorized spindle unit are calculated, analysing the harmonic response of the spindle unit. The displacement response of spindle key parts(the front surface of spindle, the midpoint of the rotor) are studied, determining the structure of spindle unit has a good dynamic performance, the rationality of the spindle unit design is validated.In this paper, the structure and static & dynamic performances are studied for the example of the electric spindle for turning. The method has certain practical and reference for use, and provide a valuable references to the electric spindle unit on the structure design and performance analysis.