Abstract
An optical measurement method based on an auto-collimator has been studied for radial error measurements of miniature ultra-high-speed spindles for miniature machine tools. This measurement method has advantages in an applicability to a small target attached to the spindle axis, a little susceptibility to electric noises and a high-speed response in comparison to other measurement methods. In this paper, the basic principle of the optical measurement method for the spindle rotation accuracy and the configuration of the trial measuring device are described, and then the measurement results of a miniature ultra-high-speed spindle with a maximum rotational speed of 200 krpm are shown.
