Compressed air control device for a source of compressed air on motor vehicles

A compressed air control device for a source of compressed air on motor vehicles, forming a unit of an electro-pneumatic unloader, an integrated electro-pneumatic multi-circuit control valve and an air-drier, comprising an inlet and an outlet provided in a common housing in which a chamber for the passage of compressed air is provided, the chamber being connected to the atmosphere via a controlled outlet valve in form of a safety valve in its opened position, a check valve being positioned downstream of the chamber, a means for alternatingly opening and closing the outlet valve and a plurality of control units of the same kind allocated to the respective circuits, the control units each comprising a check valve closing contrary to the flow direction and a means for controlled opening of the check valve. A mechanical-pneumatic unloader is integrated in addition to the electro-pneumatic unloader, the function of the mechanical-pneumatic unloader being locked in case of the source of compressed air being correctly supplied with power. The mechanical-pneumatic unloader is also designed as an on-off valve for the activation of a regeneration phase of the air-drier after the outlet valve being opened.