Abstract:
In a calibration method for a surface texture measuring instrument which measures a surface of a workpiece and includes an arm that is supported to be swingable around a base point thereof and is provided with a contact point at an end for scanning the workpiece surface, the calibration method includes a measurement step for measuring a calibration gauge of which cross section contains a part of a substantially perfect circle, an assignment step for assigning the detection results, which are obtained in the measurement step, in an evaluation formula based on a circle equation in which the center coordinates of the calibration gauge are (xc, zc) and the radius is nullrnull, and a calibration step for calibrating each parameter based on the evaluation formula obtained in the assignment step.
Abstract:
A Stylus 1 is moved along the surface of a workpiece 20 and the surface texture of the workpiece 20 is measured based on the displacement of the stylus 1 in the Z direction. A spherical reference gage of known radius is measured with the stylus 1 in advance and radius values r of the tip sphere of the stylus 1 are calculated according to angle by subtracting the radius R of the reference gage from the measured values. The actual contour of workpiece 20 is calculated by using the radius values r as the correction data according to angle and subtracting the correction values according to angle from the measured data obtained by movement along the surface of workpiece 20.