Procedure for monitoring the concentricity of a tool of a NC machine tool and NC machine tool with concentricity control

摘要

Procedure for monitoring the concentricity of a tool (3) of a NC machine tool (1), which can rotate around the Z axis, using a proximity sensor (4), where the tool (3) and the proximity sensor ( 4) they can move along the X, Y, and Z axes with respect to each other, characterized by the following steps (a) recording a distance characteristic curve (8) of the proximity sensor (4) with respect to the tool (3) at a predetermined position Z (Z0) of the tool (3) by relative displacement of the tool (3) and proximity sensor (4) in a direction (Y) at right angles to the tool axis ( Z); I (b1) place the tool (3) with respect to the proximity sensor (4) in a predetermined measurement position (X0, Y0, Zo) and store the measurement signals from the proximity sensor (4) in various rotation positions different from the tool (3) as reference signals, and (c1) for a control of concentricity of the tool (3): place the tool (3) again with respect to the proximity sensor (4) in the measurement position ( X0, Y0, Zo) predetermined, find out a difference between the current measurement signals of the proximity sensor (4) at the various different turning positions of the tool (3) and the stored reference signals, find out a concentricity deviation ( Δd) by means of the distance characteristic curve (8) from the difference, and check the tool (3) when overcoming a predetermined concentricity deviation; or (b2) place the tool (3) with respect to the proximity sensor (4) in a predetermined measurement position (X0, Y0, Zo) and store the distances of the tool (3) with respect to the proximity sensor (4 ) determined from these measurement signals by the distance characteristic curve (8) at several different rotational positions of the tool (3) as reference distances and (c2) for a control of concentricity of the tool (3): place the tool (3) again with respect to the proximity sensor (4) in the predetermined measurement position (X0, Y0, Zo), find out a concentricity deviation (Δd) from the difference between the actual distances of the tool (3), ascertained from the current measurement signals by the distance characteristic curve (8), with respect to the proximity sensor (4) at the various different turning positions of the tool (3) and the reference distances store and check tool (3) when a predetermined concentricity deviation is exceeded.