Patent ID: 8206276

Claim:
A machine tool comprising: a headstock provided with a main spindle, wherein the main spindle rotates with a tool being attached to an extremity thereof, the headstock being installed so as to be movable in an X-axis direction as a direction different from a direction of a longitudinal axis, corresponding to a Z-axis, of the main spindle; a tool post mounted on the headstock so as to be movable relative to the headstock in the direction of the Z-axis, wherein a tool can be attached to and detached from an extremity of the tool post by movements including said movement of said tool post in the Z-axis direction relative to the headstock; and a tool change unit configured so as to be movable relative to the headstock in the Z-axis direction and configured to change the tool attached to the main spindle with another tool after the extremity of the main spindle has been moved to a predetermined tool change position, and wherein when the extremity of the tool post is positioned in said predetermined tool change position, which is the same position where the tool attached to the main spindle is changed, said positioning of the extremity of the tool post in the predetermined tool changing position occurring by the movement of the headstock in the X-axis direction, and also by the movement of the tool post in the Z-axis direction, said tool change unit performs a change of the tool attached to the tool post with another tool by a tool change operation via movement of the tool change unit relative to the headstock in the Z-axis direction to remove the attached tool from the tool post and also to place another tool at the tool post for attachment thereto, which tool change operation is the same as that for the main spindle, whereby the change of the tool attached to the main spindle and the change of the tool attached to the extremity of the tool post are performed by said tool change unit and at said same tool change position.