Controller for machine tool

Abstract

A controller for a machine tool, capable of performing ultraprecision machining with high accuracy by performing correction allowing for a displacement of a spindle produced depending on a rotational speed. When the spindle is rotated at high speed, the cutting position of a tool attached to the spindle varies due to the influence of spindle fitting accuracy and of weight balance. By measuring the displacements in the X, Y and Z directions of the end of the tool attached to the spindle by means of non-contact displacement gauges, correction amounts are obtained in the manner associated with the rotational speed of the spindle, and stored in a storage device. In the process of machining, correction amounts are read depending on the speed of the spindle, and machining is performed according to program command values corrected using the correction amounts thus read. Even if the cutting position of the tool varies during high-speed rotation, machining is performed according to program command values corrected. Thus, ultraprecision machining can be carried out with high accuracy.

Dependencies are inferred from the claim text.