An apparatus and associated method for operating a machine tool having a selectively movable turret and a tool mounted to the turret. A cover is configured to be removably secured to the turret and sized so that the cover encloses the tool when the cover is secured to the turret. Turret control logic includes computer instructions stored in a computer memory and executable by a computer processor to limit movement of the turret when the cover is secured to the turret.

A machine tool includes: a lower tool rest on which a plurality of tools are mounted; a motor provided at the lower tool rest, for rotating a rotating tool when the rotating tool is mounted on the lower tool rest; and a tool holder attached to the lower tool rest, for detachably holding the tool. The tool holder has a clamping mechanism portion operating between a clamping state of clamping the tool and an unclamping state of unclamping the tool, as a result of transmission of motive power generated at the motor. With such a configuration, the clamping mechanism portion for automatically clamping and unclamping the tool held in the tool holder on the tool rest is provided with a simple configuration.

The present invention relates to a tool carrier 62 for a machine tool, in particular a lathe, having a rotary shaft drive for a numerically controllable rotary shaft B for rotating the tool carrier 62, a first tool turret head 62A carrying tools, rotatably mounted around a first turret axis, and a second tool turret head 62B carrying tools, rotatably mounted around a second turret axis, the first tool turret head 62A and the second tool turret head 62B being positioned on opposite sides of the tool carrier 62 with respect to the axis of rotation of the rotary shaft B. The present invention also relates to a machine tool, in particular a lathe, having a tool carrier 62 of this type.

In a tool exchanger apparatus of a machine tool including a turret which turns around an axis inclining with respect to a vertical direction and which conveys tools, forces applied to tool gripping portions are calculated from a resultant force of a centrifugal force, gravity and an inertial force applied to each of the tools, using a weight and a position of each of the tools and a turning speed and a turning acceleration of the turret for each of turning phases when the turret turns, and the turning speed and the turning acceleration of the turret are determined for each of the turning phases.