Method for evaluating measurement (test) signals which are generated by scanning an incremental scale (roll, graduation) with a scanning unit, and a measuring instrument (heater) for carrying out this method

摘要

In a method for evaluating measurement signals which are obtained by scanning an incremental scale 1 with a scanning unit 2, at least two basically sinusoidal and mutually phase-shifted signals sin a, cos a are generated and evaluated by a computer 5. The direction of adjustment of the scanning unit with respect to the scale is determined, and signals specifying this direction of adjustment are applied to the computer 5. The measurement signals sin a, cos a are digitized in an AD converter 8 and fed to the computer. The scanning of at least one complete signal train (flow path) is used to determine correction values for standardizing the signals sin a, cos a with reference to amplitude, the DC voltage component and the phase angle, and the computer 5 is calibrated with these correction values so that it bases the interpolative calculation of signals corresponding to incremental fractions of the graduation on a corrected signal characteristic. The number of the full graduation increments of the scale contained in the measured distance is also measured in the computer and combined with the result of the interpolation calculation before the display value. IMAGE