A force-limiting device (4) for a seat belt device which has at least two parts (5, 11, 15) controlled with a frequency-dependent, defined movement, wherein the parts (5, 11,15) moving relative to one another feature gearings (8, 10, 18, 19) engaging into each other and the frequency-dependent, controlled movement occurs such that at least one of the parts (5, 11, 15) executes a feed movement (V) with respect to the other part (5, 11,15) with an undulating motion (Q) perpendicular to the feed movement (V) in which the gearings (8, 10, 18, 19) alternatingly engage and disengage, by means of which a force limited belt extraction is facilitated. Wherein means are provided with which the required force for movement of the parts (5, 11, 15) toward one another can be automatically increased after a preset belt extraction length.