THERMAL DISPLACEMENT CORRECTION DEVICE OF MACHINE TOOL

PROBLEM TO BE SOLVED: To relatively accurately estimate a thermal displacement amount, in a thermal displacement correction device of a machine tool which estimates the thermal displacement amount of a structure of the machine tool, and corrects thermal displacement at a processing point.SOLUTION: A thermal displacement correction device 90 of a machine tool 1 comprises: a temperature sensor 70 which detects a representative temperature and a non-representative temperature of a structure of the machine tool 1; a standard temperature acquisition part 91 which acquires a standard representative temperature being a representative temperature by the sensor 70 when the structure is in a standard state, and a standard non-representative temperature being a non-representative temperature in the case that a state that a shape of the structure is within a range of a prescribed geometric tolerance is designated as the standard state of the structure when the representative temperature is a prescribed temperature; a reference temperature derivation part 92 which derives the standard non-representative temperature as a reference non-representative temperature when the structure is in the standard state, and the standard representative temperature is a prescribed temperature; and an FEM analysis part 95 which performs a structural analysis in a finite element method with the reference non-representative temperature which is derived by the reference temperature derivation part 92 as a reference temperature.SELECTED DRAWING: Figure 2 【課題】工作機械の構造体の熱変位量を推定し、加工点における熱変位を補正する工作機械の熱変位補正装置において、熱変位量の推定を比較的高精度に行うことを目的とする。【解決手段】工作機械１の熱変位補正装置９０は、工作機械１の構造体の代表温度および非代表温度を検出する温度センサ７０と、代表温度が所定温度である時に、構造体の形状が所定の幾何公差の範囲内となる状態を構造体の標準状態と定義する場合、構造体が標準状態であるときの代表温度である標準代表温度および非代表温度である標準非代表温度を、温度センサ７０によって取得する標準温度取得部９１と、構造体が標準状態であり、かつ、標準代表温度が所定温度であるときの標準非代表温度を基準非代表温度として導出する基準温度導出部９２と、基準温度導出部９２によって導出された基準非代表温度を基準温度として、有限要素法における構造解析を行うＦＥＭ解析部９５と、備えている。【選択図】 図２