Abstract
This study was performed to examine a method of clarifying the net output of high-speed or light duty spindles that is generally difficult to measure using conventional methods.To determine the relationship between windage(air friction) loss and rotational speed, a disc was attached to an electric motor-driven aerostatic bearing spindle with very low bearing friction loss. The windage(air friction) loss was calculated from the electric input currency and the voltage. The measured windage (air friction)loss was comparable to the theoretically calculated loss with hydrodynamics. Using the disc the windage(air friction) loss of which was clarified, it was possible to determine the net output of spindles, such as air turbine-driven or large bearing loss spindles.
