In order to provide an adjustment device (1), which can be driven in rotation about a longitudinal axis (2), for adjusting a cutting tool, comprising a cutting tool carrier element (3) mounted for carrying out an adjusting movement (6), a drive unit (13, 13b) for driving the cutting tool carrier element (3) and a circuit carrier element (200), which has a surface region facing the drive unit (13, 13b), for forming at least one electronic control circuit (500, 510, 520, 530) provided for controlling the drive unit (13, 13b), 13b), which allows an improved compact design so that instabilities of the main drive element, in particular a tool spindle, are better avoided and the machining space is better utilised, it is proposed that two surface points (600, 610) of the surface area (220) can be connected outside the circuit carrier element (200) by a connecting straight line (620), the end points of which are the surface points (600, 610).

A cutting head operated by a centrifugal force according to an embodiment of the present invention includes: an external housing that is rotatable; an internal housing installed within the external housing so as to be able to advance and retreat in a diameter direction, advanced toward a cut surface of a workpiece positioned outside the external housing by a centrifugal force according to rotation of the external housing, and retreated in a direction that becomes distant from the cut surface by an elastic member while the centrifugal force disappears; and a cutting tool unit provided in the internal housing and processing a groove in the cut surface while being advanced and retreated by a micro advance and retreat member.

A cutting head operated by a centrifugal force according to an embodiment of the present invention includes: an external housing that is rotatable; an internal housing installed within the external housing so as to be able to advance and retreat in a diameter direction, advanced toward a cut surface of a workpiece positioned outside the external housing by a centrifugal force according to rotation of the external housing, and retreated in a direction that becomes distant from the cut surface by an elastic member while the centrifugal force disappears; and a cutting tool unit provided in the internal housing and processing a groove in the cut surface while being advanced and retreated by a micro advance and retreat member.

In order to provide an adjustment device (1), which can be driven in rotation about a longitudinal axis (2), for adjusting a cutting tool, comprising a cutting tool carrier element (3) mounted for carrying out an adjusting movement (6), a drive unit (13, 13b) for driving the cutting tool carrier element (3) and a circuit carrier element (200), which has a surface region facing the drive unit (13, 13b), for forming at least one electronic control circuit (500, 510, 520, 530) provided for controlling the drive unit (13, 13b), 13b), which allows an improved compact design so that instabilities of the main drive element, in particular a tool spindle, are better avoided and the machining space is better utilised, it is proposed that two surface points (600, 610) of the surface area (220) can be connected outside the circuit carrier element (200) by a connecting straight line (620), the end points of which are the surface points (600, 610).