A fan and a ventilation group comprising the fan

Abstract

An axial fan has an axis of rotation and includes a hub including a bottom wall and a lateral wall extending from the bottom wall and having a peripheral edge on an opposite side with respect to the bottom wall along the axis of rotation; the fan includes a plurality of blades extending from the lateral wall externally of the hub and at least a fin internally of the hub and including an end portion projecting axially beyond the bottom wall and the lateral wall forming a cup-shaped structure of the hub, the fan including an end portion projecting axially beyond the peripheral edge externally of the hub.

1 . An axial fan having an axis of rotation and comprising
 a hub comprising a bottom wall and a lateral wall extending from the bottom wall and having a peripheral edge on an opposite side with respect to the bottom wall along the axis of rotation, the bottom wall and the lateral wall forming a cup-shaped structure of the hub, the fan comprising   a plurality of blades extending from the lateral wall externally of the cup-shaped structure;   at least a fin internal of the cup-shaped structure for generating, in use, a tangential flow of air internally of the hub, the fan being characterised in that the fin comprises an end portion projecting beyond the peripheral edge externally of the hub.   
     
     
         2 . The fan according to  claim 1  wherein the fin has a first portion extending from the lateral wall towards the inside of the hub, the end portion being defined by an at least partial extension of the first portion. 
     
     
         3 . The fan according to  claim 2  wherein the first portion is parallel to the axis of rotation. 
     
     
         4 . The fan according to  claim 1  wherein the fin comprises a second portion extending from the bottom wall towards the inside of the hub. 
     
     
         5 . The fan according to  claim 4  wherein the second portion extends radially from the axis of rotation. 
     
     
         6 . The fan according to  claim 1 , wherein the end portion extends mainly parallel to the axis of rotation. 
     
     
         7 . The fan according to  claim 1 , wherein the hub has a plurality of through-holes at a zone connecting the bottom wall and the lateral wall. 
     
     
         8 . The fan according to  claim 1 , wherein the end portion has an internal edge facing internally of the hub and an external edge, facing externally of the hub, the external edge being positioned at a radial distance from the from the axis of rotation that is less than a radial distance of the lateral wall from the axis of rotation. 
     
     
         9 . The fan according to  claim 1 , wherein the hub, the blades and the fin are made in a single part by moulding. 
     
     
         10 . A ventilation group comprising
 a fan and a support shroud of the fan,   the fan comprising an electric motor and a fan actuated by the electric motor the electric motor comprising a casing, a cap for closing the casing and a shaft to which the fan is connected,   the shroud comprising a support ring of the electric motor having an external annular wall, the ventilation group being wherein the fan is of the type according to  claim 1  and the electric motor is at least partly housed internally of the hub.   
     
     
         11 . The ventilation group according to  claim 10  wherein the external annular wall delimits, with the electric motor, an annular channel, the end portion of the fin being at least partly inserted in the annular channel. 
     
     
         12 . A ventilation group according to  claim 10 , wherein the shaft comprises an end portion, protruding from the casing on the opposite side from the cap, to which the hub of the fan is connected, the external annular wall extending axially up to the cap on the opposite side with respect to the fan. 
     
     
         13 . The ventilation group according to  claim 10  wherein the external annular wall has a radial dimension that is equal to the radial dimension of the hub.