Viable alternative to a tactile probe for an increasing number of high precision CMM applications.

For scanning purposes, the probe head is moved relative to the workpiece until the probe pin touches the surface point with a defined scanning force.

As the sensing head (20) is moved, the sensing element (22) is kept in contact with the contour (25) by generating a defined scanning force with the aid of an actuator (62).

According to one aspect of the invention, the scanning force is set on the basis of acceleration (105, 134) of the sensing element (22) relative to the sensing head (20).

Viable alternative to a tactile probe for an increasing number of high precision CMM applications.

The tactile sensing ridge (37) is designed to be contacted with the frame (15).

The probe pin has a defined position of rest relative to the probe head base.

In a method for scanning a surface point on a workpiece, a probe head having a probe head base and a probe pin, which can be moved relative to the probe head base, is provided.

As the sensing head (20) is moved along the contour (25), measured position values (28-32) of the sensing head (20) and deflections (70) of the sensing element (22) relative to the sensing head (20) are determined.

Furthermore, the means for measuring the position of the probe element (4) operates in a contact free manner.

The probe needle (25) extends parallel to the longitudinal housing axis (15) and has a probing end constructed as a probe tip (27).

It does not include other types of probing systems, such as those used in scanning mode or non-contacting probing systems.

The tones are controlled by touching an elongate sensor array (3).

Said tracer unit can be brought into interaction with the bumps and dents of the cam (24, 26) by means of at least one tracing element (30).

The tracing of said lens includes a first tracing step prior to locking said lens on the trimming means and a second tracing step subsequent to the locking step.