Abstract: A compact hydraulic unit which can be used for cooling an electric motor sufficiently for continuous operation, having an annular cylindrical pressure medium container that has an outer external wall and an inner external wall as well as two end flanges, an electric motor that is sealed and is surrounded by the pressure medium container and cooled by a cooling air stream, and a hydraulic pump driveable by an electric motor. The pressure medium container fits closely around the electric motor and the inner external wall of the pressure medium container serves as a guide means for the cooling air stream flowing over the electric motor. By this, the entire volume of air flowing between the electric motor and the pressure medium container is fully utilized for cooling the electric motor and also flows closely along the housing of the motor over the winding heads of the electric motor that are located remotely from the single fan wheel.