Investigation of dynamic response on the system stability for an integrated spindle unit
Keywords:
Spindle dynamics; Stability; Bearing contact forces; Timoshenko beam element; Solid modeling; Bearing preload.Abstract
This work presents a combined model of high acceleration end-mill spindle system by
considering the dynamics of angular contact ball bearings and cutting forces. At first the
spindle unit is analyzed by taking into consideration the centrifugal as well as the gyroscopic
conditions using Timoshenko finite aspect model. Hertz bearing contact forces are
considered at the front and back end of the spindle. Frequency response functions at the
tooltip are obtained for the dynamic spindle model which leads to plot the stability lobe
diagrams for the vertical end mill system. Furthermore an optimization study is carried out at
design stage for the bearing system and the rotor position for maximizing the chatter
vibration free cutting operation at the desired depth of cut and speed. Bearing contact forces
are considered in the model using the Hertz contact theory. For this integrated spindle-tool
unit the frequency responses are arrived at the tool-tip end. Further to validate the model, the
entire integrated unit is developed in SOLIDWORKS and its dynamic response has been
studied.
