Abstract: Using a force-measuring balancing machine (1), the empirically determined permanent calibration is corrected in that the resonant frequencies (m) of the rotor (2) to be balanced are calculated, in a translatory direction and (?2) in a rotational direction, from the mass (mR) of a rotor (2) to be balanced, which is mounted in the balancing machine (1), the co-oscillating mass (Ms) of the bearing supports (3), the rigidity (c) of the bearing supports (3) and the spacing (L) of the rotor bearings, and a frequency response calculated from the resonant frequencies (?1, ?2) and the frequency (?) of the rotor (2) is introduced to the permanent calibration.

Abstract: The chuck includes a centering clamping member having a variable diameter, a radially extending clamping surface, which is adjacent to the centering clamping member, a movable clamping element, a first spring element, via which the centering clamping member can be moved into a clamping position, a second spring element, via which the clamping element can be loaded with a first force, a third spring element, via which the clamping element can be loaded with a second, higher force, and an axially movable actuating device by which the centering clamping member and the clamping element can be moved into a release position against the force of the first and third spring elements.