| 摘要 |
PROBLEM TO BE SOLVED: To provide a machine tool capable of detecting accurately clamping and unclamping of a tool holder by a clamp mechanism arranged on the main shaft.SOLUTION: A machine tool 1 includes a main shaft 10 having a clamp mechanism 30 and a clamp detection device 40 detecting clamping and unclamping of a tool holder 2 by the clamp mechanism 30. The clamp mechanism 30 is configured so that the tool holder 2 is clamped when the draw bar 31 inserted into the main shaft 10 moves backward. The clamp detection device 40 comprises a sensor 41 detecting a position of the draw bar 31 when the clamp mechanism 30 clamps or unclamps the tool holder 2, storage means 51 of storing a position of the draw bar 31 and relative displacement calculation means 52 of calculating a displacement magnitude between a newly detected position of the draw bar 31 and a previously detected position of the draw bar 31. |
