A rotary electrical machine comprises: a stator core; a rotor core arranged at the inner periphery of this stator core; a bracket connected with one end of the stator core; a first bearing arranged by means of the bracket; a frame and a housing connected with the other end of the stator core; a second bearing arranged by means of the housing; a ventilation fan provided between the rotor core and the first bearing, with vanes provided on the outside in the axial direction; a rotor shaft that is freely rotatably supported by the first bearing and second bearing; an inlet provided in the frame or the housing; and an outlet provided in the frame or the housing.