Patent attributes
Machine-tool thermal displacement correcting device having: a tool-temperature estimating unit for recognizing—based on identification data obtained from a controller for designating, out of tools stowed in the tool-changer tool magazine, an exchange-target tool—the directly-after-use temperature of the ID'd tool, and estimating the tool temperature directly before use, based on the recognized directly-after-use tool temperature and on lapsed time, obtained from the controller, since previous use of the ID'd tool, and for estimating, based on the estimated directly-before-use tool temperature and on the spindle temperature, during-use temperature of the tool; a correction determining unit for estimating, based on the estimated during-use tool temperature, axial thermal displacement of the tool, and determining a correction amount for canceling out the displacement; and a correction executing unit for carrying out correction based on the determined correction amount.