| 摘要 |
PROBLEM TO BE SOLVED: To provide a positioning device which further properly detects an elongation amount of a ball screw, and can further improve positioning accuracy.SOLUTION: Distance detection means NXS which can detect an axial direction up to a tip of a ball screw NX is arranged at a position apart from the tip of the ball screw by an arbitrary distance being a position fixed to a base table, and temperature detection means SX which can detect a temperature of the base table BS is arranged at the base table BS. A base table reference length K at a reference temperature, and a ball screw reference length A at the reference temperature are stored in control means. Then, by using the base table reference length K, an elongation amount &Dgr;K which is acquired by calculation from the base table reference length K, and a detected temperature, and a detected distance &Dgr;X, a ball screw actual length A+&Dgr;A being a length from a reference position STX up to the other end of the ball screw NX is acquired, and a control amount of a drive motor MX which rotates the ball screw NX for positioning a movable body is corrected on the basis of the acquired ball screw length A+&Dgr;A, and the ball screw reference length A. |
