Cutting edge height measurement of a rotary cutting tool by a laser displacement sensor

This paper proposed a high speed and a high accuracy measurement method for the cutting edge height of a rotary cutting tool with respect to the reference surface on the tool by using a laser triangulation displacement sensor. In the measurement, not only the displacement output but also the light intensity output of the laser displacement sensor, which corresponds to the intensities of the laser beam reflected from the cutting tool surface, are acquired when the laser displacement sensor scans across the cutting edge. To remove the influence of the width of the cutting edge, the cutting edge height is determined from the sensor displacement output when the sensor light intensity output reaches to the maximum. It has been confirmed by theoretical analysis, computer simulation and experiment that the proposed method is effective even when the width of the cutting edge is smaller than the diameter of the laser spot of the sensor.