the following a preferred simplified embodiment is described of a variant of a furhter development of the device according to the invention the same operational parts have again been given the same reference numerals the slide housing shown in fig6 has a number of special features compared to that of fig3 this housing slides on two round slide rails 25 39 in a cylinder which are also round the cleaning water is again controlled by a valve 42 in the pipe 10 the pipe 41 of the disinfecting liquid is in the form of an overflow pipe without valve and is connected to the tank 23 which in this case is pressureless and contains the disinfecting liquid in the front part facing the seat under the cover of the slide housing 26 a first and second wiper 48 48 39 are provided for the circumferential direction of the seat they are again fastened to carriers the second carrier 49 39 being extended downwards and in addition carrying a support roller 50 39 this support roller 50 39 rests on shafts 51 51 39 supported at their ends which are fastened to the brackets 51 34 attached to the carrier 49 in the rear part of the slide housing 26 a wetting element 70 is provided which replaces the spraying device for the disinfecting liquid fig3 fig4 this wetting element is supplied with disinfecting liquid from the pressureless tank 23 whenever the wetting element 70 is positioned at a lower level than the level of the liquid in the tank 23 i e in.