Patent Application
20200147997
This patent application claims priority from Italian patent application no. 102018000010194 filed on Nov. 9, 2018, the entire disclosure of which is incorporated herein by reference.
The present invention relates to a wheel rim for a vehicle, in particular for a motor-vehicle, preferably for a motor-vehicle of the high-performance type, to which the following description will make explicit reference without thereby losing in generality.
As is known, a wheel rim is the part of the wheel, which connects the tire to the vehicle. In particular, the wheel rim and the tire thereof are normally housed in special compartments of the bodywork of the vehicle, called “wheel compartments” and delimited by arch-shaped bodywork parts known as “wheel arches”. Wheel rims of the known type have a central axis and generally comprise:
A wheel rim should be as light as possible, since it constitutes a non-suspended mass of the vehicle; thus, the wheel rim contributes to increasing the overall non-suspended mass, consequently increasing the inertia of the suspensions; basically, if the wheel rims are too heavy, the suspensions must manage greater weights and they are thus less reactive, with a consequent increase in the difficult of maintaining an optimum road grip, especially in the case of a high-performance motor-vehicle.
It should also be noted that an increase in the mass of the wheel rim determines a corresponding increase in the rotational inertia, which increases the resistance of the wheel to change the direction thereof, with effects on the responsiveness of the steering.
Another very important aspect, which must be considered in the design of a wheel rim, is the effect it has on the aerodynamics of the vehicle.
As is known, in high-performance motor-vehicles, the aerodynamics are studied to generate an elevated aerodynamic downforce (or rather an elevated aerodynamic thrust downwards) simultaneously trying to minimise the aerodynamic resistance on advancing. Consequently, the aerodynamic efficiency of a motor-vehicle is assessed according to the ratio between the aerodynamic downforce and the corresponding aerodynamic resistance on advancing: the higher this ratio is, the greater the aerodynamic efficiency of the motor-vehicle.
The wheels and with these the respective wheel rims have a significant impact on the aerodynamic resistance and thus the need is felt in the sector to adopt suitable measures to minimise the effects of such resistance.
Another problematic aspect, which must be considered in relation to the wheel rims of the known type for high-performance motor-vehicles, is the expulsion of air from the wheel compartments. For example, the radiators and the diffusers present in the front part of the motor-vehicle create airflows in the area of the respective wheels. Such flows generate an aerodynamic load on the front part of the motor-vehicle and ventilate the area of the wheels. However, the presence of the brake discs of the wheel rims and tires tends to close the wheel compartments, in use, with consequent difficulties in expelling the air entering such spaces; the result is a sort of “inflation” of the wheel compartments, with an increase in local pressure due to the fact that the speed of the air entering the wheel compartments is greater than that being expelled from the same.
Thus, the need is felt in the sector to improve the expulsion of air by the wheel rims during the travel of the vehicle in the forward direction.
It is an object of the present invention to produce a wheel rim for a vehicle, in particular for a motor-vehicle, which allows at least one of the aforesaid needs to be met in a simple and inexpensive manner.
According to the present invention, a wheel rim is made for a vehicle, in particular for a motor-vehicle, as claimed in claim 1 and in the claims dependent thereon.
The present invention also relates to a vehicle as claimed in claim 7.
The present invention will now be described with reference to the accompanying drawings, illustrating a non-limiting embodiment thereof, wherein:
A front portion of a vehicle is partially shown in
Each wheel compartment 5 is delimited at the side by an arch-shaped bodywork element known as a wheel arch 6.
The outer body 4 comprises, amongst other things, a front bonnet 7, a front bumper 8, two sides 9 (only one of which is partially visible) and including respective doors 10, and a windscreen 11. Furthermore, in the front area between the bonnet 7 and the bumper 8, one or more air intakes 12 can be present, which, together with respective openings 13 obtained in the wheel arch 6 adjacent thereto, allow, during the forward travel of the motor-vehicle 1, the generation of airflows, which cross the relative wheel compartment 5.
Further airflows towards the wheel compartments 5 are generated by the radiator (known in itself and not shown), which is usually placed at the front inside the engine compartment of the motor-vehicle 1, and/or by the diffuser (also known per se and not shown), positioned on the bottom of the motor-vehicle 1.
Some of the aforesaid air flows, which cross, for example, the front wheel compartment 5, placed on the left-side drive, and the respective wheel 3 are indicated by the arrows F in
With reference to the appended figures, each wheel 3 essentially comprises a wheel rim 15, made according to the teachings of the present invention and fixed, in use, in a known manner, to a relative suspension (also known and not shown) of the motor-vehicle 1, and a tire 16 mounted peripherally onto the wheel rim 15.
In particular, the wheel rim 15 has an axis A, coinciding, in use, with the axis of the wheel 3, and comprises:
As can be seen, in particular, in
Advantageously, the wheel rim 15 further comprises one or more projections 23, in this case shown in an equal number to the number of the spokes 20 protruding in a cantilever fashion towards the hub 17, starting from a radially innermost surface 24 of the peripheral ring 18, opposite to the radially outermost surface 19, and defining an airfoil 25 (see, in particular,
In particular, the flow of air across the wheel rim 15 as diverted by the projections 23 is shown by way of example, by the arrows F, in
As can be seen in the attached figures, each projection 23 is arranged in a position circumferentially interposed between two spokes 20 adjacent thereto.
Each projection 23 further has a configuration tapered towards the free end thereof, facing the hub 17.
With particular reference to
In greater detail, with reference to the rotation direction, in use, of the wheel rim 15 during the forward travel of the motor-vehicle 1 (anti-clockwise in
Each wheel rim 23 is delimited by a first curvilinear surface 28 facing the front opening 22 and by a second curvilinear surface 29 facing the rear opening 21; the airfoil 25 associated with each projection 23 has (FIG. 3a) a back 30 defined by the curvilinear surface 28 and a belly 31 defined by the curvilinear surface 29; the back 30 and the belly 31 mutually connecting the attack edge 26 to the output edge 27.
As can be seen in detail in
With reference to
As can be noted from
More specifically, as can be seen in
In this way, it is also possible to obtain the following further effects:
Finally, it is clear that modifications and variations can be made to the wheel rim 15 and to the motor-vehicle 1 described and illustrated here, without thereby departing from the scope of protection defined by the claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 102018000010194 | Nov 2018 | IT | national |
