High Speed Machining spindles fulfill a great number of technical functions in a reduced and confined environment. In the aerospace industry, spindles have very high power and speed capabilities. The dm.N criterion, representing the criticality of the application for rolling bearings, is extremely high. It is therefore difficult to predict their coupled and complex behavior. This work aim at proposing a strictly minimal dynamic model to ease new spindle design and to optimize the cutting conditions in an industrial environment. In this context, a phenomenological approach is selected. First, a detailed model of the angular ball bearing is built. Dynamic effects on balls and macroscopic deformations of rings are included in the five degrees of freedom analytical model. A new exact analytical formulation of the stiffness matrix is proposed and validated. Then, the axial behavior of a spindle with double preload is updated. The experimental results are obtained with a new testing device designed to apply bidirectional axial loads on the spindle at any given speed. At the process‘s end, preload parameters are identified. More importantly new essential physical phenomena are found, enabling a better understanding of the complex and coupled axial behavior of the spindle: radial expansion of the bearing rings, the presence of a stroke limit, centrifugal axial shrinking and solid friction of preload device. Finally, an electromagnetic actuator is developed to study the three-dimensional behavior of the spindle. A time domain model of the spindle in Finite Elements is built including the complete updated bearing model. Simplifying hypotheses for the integration of the bearing model are studied. In the case of a stiff bending rotor and a high preload, a linear model of the bearing can be selected once the axial dynamic and non-linear equilibrium is reached. At the end, both numerical and experimental Frequency Response Functions are compared and analyzed. Frequency evolution and mode coupling with shaft speed are investigated thanks to the complete numerical model developed in this work.
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