Spindle Housing Design Parameter Optimization Considering Thermo-Elastic Behaviour

Abstract

This paper presents a simulation method for predicting thermo-elastic behaviours of spindle-bearing system and an optimization procedure for housing design parameters in relation to various spindle-bearing operating and surrounding conditions such as assembling tolerance, geometric dimension, cooling condition and thermal deformation. The numerical formulation of transient thermo-elastic behaviours as a function of major spindle-bearing system design parameters is developed using the design of experiment methodology. The spindle-bearing analysis program has also been suggested in this paper. The suggested modelling and optimization method not only considers thermal deformation or heat transfer, but eventually it includes the nature of thermo-elastic interaction within spindle, bearing, housing and surrounding conditions in terms of formulating the objective function describing thermo-elastic characteristics such as friction moment, heat generation, contact mechanism, thermal displacement, assembly tolerance change, bearing internal clearance and spindle stiffness change and the dynamically changing operating conditions of the spindle. In order to substantiate the method, this paper shows a numerical example of formulation and optimization results for spindle housing design parameters with consideration of thermo-elastic behaviours as the thermal displacement, the preload increase, and the preload fluctuation.