| 摘要 |
PROBLEM TO BE SOLVED: To accurately correct the thermal displacement of a machine tool under the full operating condition by estimating the thermal displacement amount in the transient state after the change of the number of revolution by means of an exclusive method. SOLUTION: The temperature of a main spindle 3 is digitized and measured by a temperature measuring device 8 on the basis of the outputs of temperature sensors 6, 7 and recorded as the time series data into a temperature recording device 9. A thermal displacement estimating calculator 10 estimates the thermal displacement amount on the basis of the immediate value of the measured temperature in the steady state in which the temperature is saturated, and the thermal displacement amount is estimated on the basis of the time series data of the last time by the time constant ratio of the temperature to the thermal displacement with time in the transient state after the number of revolutions is changed. An NC device 11 corrects the thermal displacement of the main spindle 3 by the correction amount based on the thermal displacement estimated value. |
