| 摘要 |
<p>PROBLEM TO BE SOLVED: To eliminate deterioration of positioning accuracy due to change of length of a ball screw and length of a basis due to heat, thereby to improve machining accuracy of a machine tool or the like.SOLUTION: A movable body 3 driven by a ball screw 12 is disposed on a basis 26 by means for supporting one end of the ball screw 12 rotatably and movably in an axial direction, and a displacement detector 24 for detecting displacement of one end of the ball screw and a temperature detector 27 for detecting temperature of the basis are disposed. Based on the measurement values measured by them, an actual thermal displacement amount of the ball screw is calculated, not a tinsel thermal displacement amount, thereby positioning control can be performed correctly.</p> |
