Machine tool and control apparatus of the machine tool

A control apparatus of a machine tool comprising:

• a workpiece holding unit to hold a workpiece;
• a tool rest to hold a cutting tool for cutting the workpiece;
• a feeding unit to feed the cutting tool toward the workpiece in a predetermined feeding direction via relative movement between the workpiece holding unit and the tool rest;
• a repetitive movement unit to repetitively move the workpiece holding unit and the tool rest in a mutually relative manner by repeating the relative movement in the feeding direction at a first speed and a second speed that are mutually different;
• and
• a rotating unit to relatively rotate the workpiece and the cutting tool;
• wherein the machine tool is capable of machining the workpiece via the relative rotation between the workpiece and the cutting tool and via the feeding of the cutting tool toward the workpiece with the repetitive movement;
• and
• wherein the repetitive movement unit is configured so that the cutting tool performs one repetitive movement with respect to multiple relative rotations between the workpiece and the cutting tool and so that a rotation angle of the relative rotation during the relative movement at the second speed is smaller than a rotation angle of the relative rotation during the relative movement at the first speed in one repetitive movement.