Method for positioning a center point on a geometric axis in a machine tool

A method for positioning a centre point of a second machine tool unit of a machine tool on a geometric axis of a first machine tool unit of the machine tool, wherein the second machine tool unit has a circular path that is concentric with the centre point, is scannable and lies on a circular cylindrical surface, and wherein the first machine tool unit has a component that is rotatable about an axis of rotation coincident with the geometric axis, comprising

• arranging a measuring unit on the first machine tool unit in a defined manner relative to the geometric axis and establishing by means of the measuring unit the position of the circular path in a geometric plane, defined by the circular path, relative to the geometric axis, ascertaining the position of the circular path ascertained by means of the measuring unit by establishing the positions of three measurement points arranged at defined angular spacings from one another over the circular path relative to the geometric axis, calculating the position of the centre point of the circular path in the geometric plane relative to the geometric axis and a reference direction running through the geometric axis on the basis of the positions of the measurement points and the known radius of the circular path, and calculating adjustment paths in the geometric plane, which are associated with the adjustment directions, for positioning the centre point on the geometric axis by using machine tool-based adjustment directions of the machine tool units relative to one another, and moving the machine tool units relative to one another in accordance with these adjustment paths.