Cycling helmet with high aerodynamic efficiency

Abstract

An aerodynamic cycling helmet is described, comprising a shell developed along a longitudinal direction, from a front area to a rear area, the said rear area extending beyond an inner portion of the shell provided with an occipital support of the head, the said shell being symmetrical with respect to a longitudinal plane of symmetry containing the longitudinal direction and extended in two opposing side walls from a temporal area and the area of the ear to the rear area. On each of the side walls, the helmet is provided with a respective air intake, which is open and passing through the shell and the shell includes in the rear area, within the shell, respective surfaces for channelling the flow of air that are capable of straightening, parallel to the longitudinal direction, the air flow derived from each of the air intakes and of channelling the flow, within the shell, in the direction of the rear area of the shell.

1 . An aerodynamic cycling helmet comprising a shell developed along a longitudinal direction (X), from a front area to a rear area, the rear area extending beyond an inner portion of the shell provided with an occipital support of the head, the shell being symmetrical with respect to a longitudinal plane of symmetry (S) containing the longitudinal direction (X) and being extended in two opposing side walls extending from a temporal area and the area of the ear to the rear area, the shell having a transverse cross-section of greatest dimension transverse to the longitudinal direction, such cross-section being defined by the intersection of the shell with a plane (M) perpendicular to the longitudinal plane of symmetry (S) and perpendicular to the longitudinal direction (X), -comprising on each of the side walls, a respective air intake, which is open and passing through the shell, located in an area of the shell between the transverse cross-section of greatest dimension and the rear portion of the shell, essentially behind the occipital support area, and by the fact that the shell comprises in the rear area, and within the shell, respective surfaces for channelling the flow of air, capable of straightening, parallel to the longitudinal direction (X), the air flow derived from each of the intakes and of channelling this flow, within the shell, in the direction of the rear area of the shell, so as to impart to the current of the flow, as it exits the shell, a directional component that is predominantly axial, parallel to the longitudinal direction (X). 
     
     
         2 . The cycling helmet according to  claim 1 , wherein, starting from each of the air intakes and extending in the interior of the shell, there is a respective surface portion for channelling the air flow, derived from the corresponding air intake, in the direction of the rear area, cooperating, in the function of straightening the air flow, with a directional tailpiece provided at the centre of the rear area of the shell, the tailpiece having a symmetrical shape with respect to the plane of longitudinal symmetry (S) and comprising opposing faces developed parallel to the plane of symmetry (S), each of the faces cooperating with the corresponding channelling surface portion facing it, to straighten the air flow derived from the corresponding air intake as it exits the rear area of the helmet. 
     
     
         3 . The cycling helmet according to  claim 2 , wherein each channelling surface portion has an extrados surface profile that diverges from the course of the shell profile contiguous with it, starting from the corresponding air intake in the direction of the rear area, so as to define, in the rear area of the shell, together with the directional tailpiece, the shell outlet section for the air flow derived from the corresponding air intake and straightened by the channelling surfaces. 
     
     
         4 . The cycling helmet according to  claim 3 , wherein the profile of the extrados surface of each of the channelling surface portions is conceived as a wing profile, of the type prescribed according to the NACA classification. 
     
     
         5 . The cycling helmet according to  claim 1 , wherein the sectional profile of each of the air intakes develops in a plane perpendicular to the longitudinal direction of extension (X) of the helmet. 
     
     
         6 . The cycling helmet according to  claim 2 , comprising an extension element of the directional tailpiece, which is removably attached to the tailpiece at its free extremity, to increase the surface breadth of the corresponding faces of the directional tailpiece. 
     
     
         7 . The cycling helmet according to  claim 1 , comprising in the front area of the shell at least a first pair of ventilation apertures, passing through the thickness of the shell and made symmetrical with respect to the longitudinal plane of symmetry (S), the ventilation apertures being capable of being selectively shut off by a closure element capable of being removably attached to the ventilation apertures. 
     
     
         8 . The cycling helmet according to  claim 7 , wherein the closure element has a shape such that it is flush with the outer surface of the shell, when attached to close the ventilation apertures. 
     
     
         9 . The cycling helmet according to  claim 7 , wherein there is a second pair of ventilation apertures, passing through the thickness of the shell, provided in the rear area of the shell, symmetrical with respect to the longitudinal plane of symmetry (S). 
     
     
         10 . The cycling helmet according to  claim 1 , including on the extrados surface of the shell a dorsal ridge extending longitudinally from the front anterior area in the direction of the rear area, which has a symmetrical shape and arrangement with respect to the longitudinal plane of symmetry (S) of the helmet. 
     
     
         11 . The cycling helmet according to  claim 1 , wherein provision is made for a visor capable of being removably attached to the front area of the shell. to  12 . The cycling helmet according to  claim 8 , wherein there is a second pair of ventilation apertures, passing through the thickness of the shell, provided in the rear area of the shell, symmetrical with respect to the longitudinal plane of symmetry (S).