Abstract: An axial fan with reversible flow direction comprises a rotor (11), which is driven by a variable speed-controlled driving motor (14) and is provided with adjustable rotor blades (13) fitted around a rotational axis. The rotor (11) is preceded by an inlet stator (15) and followed by a downstream stator (16), which are each provided with guide vanes (17, 18). The guide vanes (17, 18) of the inlet stator (15) and the downstream stator (16) are designed so as to be mirror-symmetrical to the radial center plane of the rotor (11) and may be adjusted at an angle to the direction of flow in such a way that—when the flow direction is reversed—the inlet stator (15) takes on the function of a downstream stator and the downstream stator (16) takes on the function of an inlet stator.

Abstract: A method and apparatus for lubricating the bearings associated with rotor mounted variable pitch type blades in axial flow fans.