The invention relates to an air supply device (1) for a pneumatic spring system (9) of a vehicle, comprising an air filter as a processor (2) for incoming air, an inlet air line (3), an outlet air line (4), a compressor (5), and optionally an air drier (6), wherein the inlet air line (3) and the outlet air line (4) are decoupled by a first and a second check valve (7, 8) and the processor (2) is arranged between the compressor (5) and the first or second check valve (7, 8).