MACHINE TOOL DISPLACEMENT CORRECTING APPARATUS

摘要

The history of function values of the spindle speed of a main spindle in each past time-range based on the present point of time is stored in a history data table (22D). Correction coefficients are stored in a correction coefficient table (22C) in advance in relation to the storage positions in the history data table (22D). Each storage position and correction coefficient is read from the correction coefficient table (22C), and the function value of the spindle speed of the main spindle which corresponds to the storage position is read from the history data table (22D). A correction value is calculated on the basis of the sum of the products of the function value and correction coefficient for each storage position, and an NC instruction position is corrected by this correction value.