Measurement of Motion Accuracy and Improvement of Machining Accuracy on Ultra-high Precision NC Machine Tools by Using Cross Grid Encoder Test

摘要

The Cross Grid Encoder is a two-dimensional position detector superior to conventional optical scales in terms of flexibility on measurement paths. In the circular interpolation tests, the measurement with small radii and/or high feed rates is available by using this system, which the Ball Bar test can't afford. In addition, the complicated paths which consist of interpolated lines and circles are also available, it is possible to obtain the beneficial information for the improvement of the motion accuracy. In this paper, several measurement results are shown on the motion accuracy of a ultra-high-precision grinding machine, and the causes which deteriorate the motion accuracy are discussed. It is also shown that the motion errors can be decreased by adjusting and improving the machine structure.