Electric fan unit comprising: a casing defining a passage for an air flow, having an inlet and an outlet, and comprising a central support positioned between said inlet and outlet, a fan mounted on said central support and rotatable about its own axis of rotation (z), a shutter comprising a system of slats movable between a configuration in which the passage is completely open and a configuration in which it is completely closed, and a centrifugal regulator having - a base element connected rotationally to the fan, - an axially movable actuator member connected for operation to the system of slats in order to move them towards their maximum opening configuration when the fan is activated, - at least two articulated arms (52, 54) connecting the actuator member to the base element, each of said articulated arms including a centrifugal weight and being movable by centrifugal force in such a way as to cause the axial advance or retraction of said actuating member, and - a slidable coupling (84, 86) to guide the axial translational movement of the actuating member relative to the base element; said electric fan unit being characterized in that it comprises an axle connected fixedly to said central support, on which said fan is mounted rotatably, said axle defining the axis of rotation (z) of the fan and having a through cavity within which a rotating shaft is coaxially housed, a front end of this shaft being connected fixedly to said fan, while a rear end of the shaft is connected fixedly to said base element of the centrifugal regulator, said base element being mounted rotatably on the axle, on the opposite side of the central support from said fan. a casing defining a passage for an air flow, having an inlet and an outlet, and comprising a central support positioned between said inlet and outlet, a fan mounted on said central support and rotatable about its own axis of rotation (z), a shutter comprising a system of slats movable between a configuration in which the passage is completely open and a configuration in which it is completely closed, and a centrifugal regulator having - a base element connected rotationally to the fan, - an axially movable actuator member connected for operation to the system of slats in order to move them towards their maximum opening configuration when the fan is activated, - at least two articulated arms (52, 54) connecting the actuator member to the base element, each of said articulated arms including a centrifugal weight and being movable by centrifugal force in such a way as to cause the axial advance or retraction of said actuating member, and - a slidable coupling (84, 86) to guide the axial translational movement of the actuating member relative to the base element; - a base element connected rotationally to the fan, - an axially movable actuator member connected for operation to the system of slats in order to move them towards their maximum opening configuration when the fan is activated, - at least two articulated arms (52, 54) connecting the actuator member to the base element, each of said articulated arms including a centrifugal weight and being movable by centrifugal force in such a way as to cause the axial advance or retraction of said actuating member, and - a slidable coupling (84, 86) to guide the axial translational movement of the actuating member relative to the base element; said electric fan unit being characterized in that it comprises an axle connected fixedly to said central support, on which said fan is mounted rotatably, said axle defining the axis of rotation (z) of the fan and having a through cavity within which a rotating shaft is coaxially housed, a front end of this shaft being connected fixedly to said fan, while a rear end of the shaft is connected fixedly to said base element of the centrifugal regulator, said base element being mounted rotatably on the axle, on the opposite side of the central support from said fan.