COMPRESSED AIR SYSTEM FOR THE AIR SUPLY OF LOAD VEHICLES

The invention relates to an air treatment system for the supply of compressed air in utility motor vehicles, having a plurality of compressed-air circuits connected to a main supply line (102), wherein a trailer and/or parking brake supply line (110) is connected to a supply line (108) of one or more other compressed-air circuits, and wherein, in the trailer and/or parking brake supply line (110), there is provided a valve arrangement (112) which automatically opens at a predefined supply pressure and which can additionally be pneumatically pilot-controlled into an open position. In said air treatment system, it is also provided that the valve arrangement (112) has a directional valve (114, 114'), which is open in a first valve position and which, in a second valve position, forms a check valve, said check valve opening in the direction of a trailer and/or parking brake supply port (23, 25) and being loaded in a closing direction by a preload spring (32), and has a flow transfer valve (OV23), which is positioned downstream of the directional valve (114, 114') and which opens at a predefined opening pressure.