Method and device for measuring a surface profile

A method for measuring a surface profile of a workpiece, said method comprising the following steps:

• during measurement, a measuring carriage (15) is moved in a straight line at a distance from the workpiece surface (11) in a moving direction (x);
• a free probe end (40) of a probe tip (25) fastened to the measuring carriage (15) rests on the workpiece surface (11) to be measured with a measuring force (Fm) and glides over the workpiece surface (11) along moving direction (x);
• a deflecting value (s) is detected, said deflecting value describing the deflection (zT) of the probe end (40) in a measuring direction (z) extending transversely to moving direction (x);
• and,
• a measuring force change value (Fdyn) describing the actual change of the measuring force (Fm) between the probe end (40) and the workpiece surface (11) is determined independent of the deflecting value (s);
• providing a pre-specified measuring force target range (Fo, Fu) for the measuring force value (Fm), whereby an exact measurement can occur within said range;
• and,
• generating a previously specifiable static contact force (Fstat) between the probe end (40) and the workpiece surface (11).

Measuring device (10) for measuring a surface profile of a workpiece, said device comprising,

• a measuring carriage (15) having a plurality of carriage positions, the measuring carriage (15) during measurement carried by and movable via a carriage drive (16) in a straight line at a distance from the workpiece surface in a moving direction (x),
• a probe tip (25) provided on the measuring carriage (15), a free probe end (40) of said probe tip (25) in operative position resting on the workpiece surface (11) to be measured with a measuring force (Fm) and the free probe end (40) being deflectable in a measuring direction (z) transverse to the moving direction (x),
• a measured value receiver (45) in operative arrangement with the probe tip (25) and for detecting a deflecting value (s) describing a deflection (zT) of the probe end (40) in the measuring direction (z),
• an analyzing unit (21) in operative arrangement with the carriage drive (16) and the measured value receiver (45), the analyzing unit (21) for determining a measuring force change value (Fdyn) describing the change of the measuring force (Fm) between the probe end (40) and the workpiece surface (11) as a function of the deflecting value (s), the analyzing unit (21) is provided with a pre-specified measuring force target range (Fo, Fu) for the measuring force value (Fm), whereby an exact measurement can occur within said range, the analyzing unit (21) for generating a measuring error signal when the measuring force value (Fm) is outside the measuring force target range (Fo, Fu), and,
• a force setting device (35) that can be activated by the analyzing unit (21) is provided, said force setting device (35) for generating a previously specifiable static contact force (Fstat) between the probe end (40) and the workpiece surface (11).