The FEM Analysis Of Dynamic And Static Characteristics Of High Speed Motorized Spindle

High speed machining (HSM) is a promising technology for significantly increasing productivity and reducing production costs. Development of high-speed spindle technology is strategically critical to the implementation of HSM. Compared to conventional spindles, and motorized spindles are equipped with built-in motors for better power transmission and balance to achieve high-speed operation.However, the built-in motor introduces additional mass to the spindle shaft, besides, since its very high working speed, some high-speed rotational effects, including centrifugal forces and gyroscopic moments on the spindle shaft can not be ignored in the analysis as is done in conventional spindle, thus complicating its mechanical-dynamic behaviors.This thesis presents some integrated models to study the dynamic and static characteristics of the motorized spindle in FEM based on the software ANSYS. Specific details of the thesis are as follows:(1) The structure of the high-speed motorized spindle is well studied, besides, two key parameters, the span between the two pairs of bearings as well as the interference depth between motor rotor and the shaft, needed at the stage of designing are analyzed in detail to find the optimal value or range of the design sets.(2) By modeling and studying force characteristics of Angular Contact ball bearing based on Hertz Contact Law, the static rigidity of bearing used in motorized spindle is calculated considering the variation of the contact angle with the effect of the axial preload. In addition, the damping coefficient of the bearings needed in the dynamic characteristics analysis is solved according to the experiential formula.(3) A FEM model of the motorized spindle is established in ANSYS, which is applied to solve the static rigidity of motorized spindle. Also, the influence of preload on the static rigidity of motorized spindle is studied in detail.(4) The general dynamic model of the motorized spindle is set up to research on its dynamic characteristics in theory with an eye to high-speed rotational...