rotary knob wall section which recess is bounded by the rib 9 the stationary stop rib 8 of the overturning prevention device according to the invention can be arranged as shown in fig1 on the front of the front plate 2 for example welded adhesively bonded or otherwise nondetachably fastened to this in the context of the invention however the stop rib 8 can also be provided on the housing 3 containing the switching means 4 or u2014 as already mentioned above u2014 on a securing disc which in turn is arranged on the front plate of a switch panel the latter variant has the substantial advantage that the overturning prevention device according to the invention in turn consisting of ribs arranged on the rotary knob and on the securing disc and capable of striking one another can be adapted to known rotary switches or even mounted subsequently on already installed rotary switches without great expense thus commercial rotary switches can readily be equipped with the overturning prevention device according to the invention for which purpose in a first step the securing disc is then mounted on the front plate and the switch housing is then fastened thereto which can be.