Vehicle wheel rim and method for improving the energy efficiency of a vehicle wheel rim

Abstract

A vehicle wheel rim comprises: - a main body (2) comprising a peripheral bead seat (3), defining in the rim a groove for seating a vehicle tyre, a centre flange (4) for coupling the rim to a vehicle wheel hub and a centre portion (5) for connecting the peripheral bead seat (3) to the centre flange (4), the centre portion (5) having at least one air flow opening (7), - at least one panel (8), coupled to the opening (7), movable between a closed position (P1), where it closes at least part of said opening (7) thereby obstructing an air flow through the opening, and an open position (P2), where said opening (7) is accessible and allows the air to flow through, a drive unit (9), coupled to the panel (8) and configured to move said panel (8) between the closed position (P1) and the open position (P2) as a function of a temperature variation in the drive unit (9), the drive unit (9) comprising an actuator (10), made of a shape memory alloy, configured to vary its length as a function of the temperature variation and to exert a predetermined force, the drive unit (9) comprising a transmission apparatus (11) adapted to transmit said force from the actuator (10) to said panel (8) to move it between the closed position (P1) and the open position (P2), the actuator (10) having a respective first end (10A), fixed to the centre portion (5) and a second end (10B) fixed to the transmission apparatus (11).

Description

DescriptionTitle of Invention: VEHICLE WHEEL RIM ANDMETHOD FOR IMPROVING THE ENERGY EFFICIENCY OF A VEHICLE WHEEL RIMTechnical Field

[0001] This invention relates to a vehicle wheel rim and to a method for improving the energy efficiency of a vehicle wheel rim.Background Art

[0002] Generally speaking, it is important for vehicles, in particular sports vehicles, to have wheel rims with multiple openings to ensure that the brake system, which overheats when the brakes are applied, is cooled by the air flowing through the openings.

[0003] Usually, the rims have a plurality of spokes which define a plurality of openings in the wheel rim.

[0004] Such openings allow air to flow through when the vehicle is moving.

[0005] The air flow allows the brake system to be cooled.

[0006] Disadvantageously, however, when the vehicle is moving, these openings produce a large amount of aerodynamic resistance which impacts negatively on the performance of the vehicle.

[0007] There is therefore a need to overcome the drawbacks of prior art solutions.Aim of the invention

[0008] The aim of this invention is to at least meet the above-mentioned need by providing a wheel rim and a method which can ensure adequate cooling of the brake system while at the same time improving the performance of the vehicle.

[0009] At least said aim is achieved by the invention as characterized in the independent claims.

[0010] The dependent claims correspond to possible different embodiments of the invention.

[0011] According to an aspect of it, this disclosure relates to a vehicle wheel rim.

[0012] The wheel rim comprises a main body comprising a peripheral bead seat, defining in the rim a groove for seating a vehicle tyre, a centre flange for coupling the rim to a vehicle wheel hub and a centre portion for connecting the peripheral bead seat to the centre flange.

[0013] The centre portion has at least one air flow opening.

[0014] Advantageously, the opening allows air to flow through, which is of fundamental importance when the wheel rim is in use.

[0015] In particular, when the wheel rim is in use, the opening ensures that enough air flows through it to cool the brake system of the vehicle.

[0016] When the vehicle is braked, the brake system overheats and the heat must be dissipated in order to prevent the brake system from reaching excessively high temperatures.

[0017] The air which enters through the opening of the wheel rim allows removing the heat and cooling the brake system.

[0018] In an example, the centre portion has a plurality of openings to allow the air to flow through.

[0019] The wheel rim comprises at least one panel, coupled to the opening, movable between a closed position, where it closes at least part of said opening, thereby obstructing an air flow through the opening, and an open position, where the opening is accessible and allows the air to flow through the opening.

[0020] When the brakes are applied, and thus when the brake system is active, it is fundamental that the air flow be allowed to pass through the opening in order to cool the brake system if the temperature conditions of the brake disc so require.

[0021] This is made possible when the panel is at the open position and the air flow can pass through the opening of the wheel rim substantially undisturbed.

[0022] If the brake system is active but does not determine an increase in the temperature of the drive unit, the panel remains at the closed position.

[0023] If the vehicle is in motion and the brake system is not active, being able to close the opening with the panel allows reducing the aerodynamic resistance created by the opening of the wheel rim.

[0024] When the panel is at the closed position, the wheel rim is substantially closed or solid.

[0025] Advantageously, positioning the panel at the closed position allows reducing the aerodynamic resistance, varying the aerodynamic load of the vehicle provided by the wheel rim and improving the performance of the vehicle.

[0026] The wheel rim comprises a drive unit coupled to the panel.

[0027] Advantageously, the drive unit allows moving the panel.

[0028] In particular, the drive unit is configured to move said panel between the closed position and the open position as a function of a temperature variation in the drive unit.

[0029] In other words, if the temperature of the drive unit varies, the drive unit itself is configured to move the panel between the closed position and the open position.

[0030] The temperature variation is generally caused by the vehicle brake system being activated or not activated.

[0031] When the brake system is activated, it heats up and causes the components near it, including the drive unit, to heat up as well.

[0032] When the drive unit heats up, the panel is moved to the open position by the drive unit itself.

[0033] According to an aspect, the drive unit can move the panel to intermediate positions between the closed position and the open position.

[0034] Such intermediate positions are adopted as a function of the temperature of the drive unit.

[0035] As the air flows through the opening, the brake system cools and, consequently, the drive unit also cools.

[0036] As the drive unit progressively cools, the panel is moved to the intermediate positions until it reaches the closed position.

[0037] Following the cooling of the drive unit, the panel is moved from the open position to the closed position by the drive unit itself.

[0038] The drive unit comprises an actuator, made of a shape memory alloy, configured to vary its length as a function of the temperature variation and to exert a predetermined force.

[0039] In other words, the actuator exerts a pushing action which is transmitted to the panel so as to move it from the closed position to the open position.

[0040] According to an aspect, the actuator is longer when it is in a heating-up condition than when it is not in a heating-up condition.

[0041] In other words, when the actuator is heated, it is longer than when it is not heated.

[0042] The drive unit comprises a transmission apparatus adapted to transmit the force from the actuator to the panel to move it between the closed position and the open position.

[0043] The panel may be movable between the open position and the closed position by rotation.

[0044] The transmission apparatus may thus be configured to rotate the panel between the open position and the closed position.

[0045] According to an aspect, the transmission apparatus is configured to move the panel to intermediate positions between the closed position and the open position.

[0046] In particular, the transmission apparatus is configured to move the panel to intermediate positions between the closed position and the open position.

[0047] The actuator has a respective first end fixed to the centre portion and a respective second end fixed to the transmission apparatus.

[0048] According to an aspect, the drive unit comprises an elastic opposing element, coupled to the transmission apparatus.

[0049] The elastic opposing element is configured to oppose the force exerted by the actuator.

[0050] Therefore, in order to move the transmission apparatus, the actuator has to overcome the resistance exerted by the opposing element.

[0051] Following a temperature variation, the actuator changes its length between a first length (when not heated) and a second length (reached when the actuator itself heats up).

[0052] If the actuated is heated and has the second length, it exerts a force such as to overcome the resistance of the elastic opposing element and to move the transmission apparatus so as to bring the panel to the open position.

[0053] As the actuator cools down as a result of the air flowing through the opening, its length is reduced until reaching the first length and the elastic opposing element moves the transmission apparatus so as to bring the panel to the closed position.

[0054] According to an aspect, the elastic opposing element has a respective first end fixed to the centre portion and a respective second end fixed to the transmission apparatus on the opposite side with respect to the second end of the actuator.

[0055] According to an aspect, the actuator has, along one direction, a second length when the panel is at the open position, and a first length when the panel is at the closed position.

[0056] In a preferred example, the first length is less than the second length.

[0057] In an example, the actuator has a spring structure.

[0058] The transmission apparatus may comprise a transmission element.

[0059] The transmission element may be disposed between the actuator and the elastic opposing element.

[0060] The actuator is configured to move the transmission element between a first position, where the panel is at the open position, and a second position, where the panel is at the closed position.

[0061] The transmission apparatus comprises a rod having a first end and a second end, both fixed to the panel.

[0062] The rod may be coupled to the actuator by the transmission element.

[0063] The transmission element is configured to rotate the rod about an axis.

[0064] Advantageously, the rod allows the movement of the drive unit and, in particular, of the transmission apparatus to be transmitted efficiently to the panel.

[0065] According to an aspect, the first end of the rod is fixed to the panel by a first connecting element and the second end of the rod is fixed to the panel by a second connecting element.

[0066] In an example, the centre portion comprises a plurality of spokes extending between the peripheral bead seat and the centre flange.

[0067] Each pair of spokes defines an air flow opening.

[0068] The actuator may have its respective first end fixed to a first spoke of the pair of spokes which define the air flow opening.

[0069] The elastic opposing element may have its respective first end fixed to a second spoke of the pair of spokes which define the air flow opening.

[0070] According to an aspect of it, this disclosure relates to a method for improving the energy efficiency of a wheel rim.

[0071] The method comprises:

[0072] - providing a rim comprising a main body comprising a peripheral bead seat, defining in the rim a groove for seating a vehicle tyre, a centre flange for coupling the rim to a vehicle wheel hub and a centre portion extending between the peripheral bead seat and the centre flange, the centre portion having at least one air flow opening, and the rim comprising at least one panel coupled to the opening;

[0073] - moving the panel, as a function of a temperature variation, between a closed position, where it closes at least part of the opening, thereby obstructing the air flow, and an open position, where the opening is accessible and allows the air to flow through it.

[0074] Advantageously, moving a panel to open and close an opening of the wheel rim allows improving the energy efficiency of the wheel rim.

[0075] In the case of high temperatures, the panel is moved so as to make the opening accessible to allow dissipating the heat which accumulates in the wheel rim.

[0076] As the temperature falls, the panel can be moved so as to close the opening and thus reduce the aerodynamic resistance of the wheel rim.Brief description of the drawings

[0077] The main features of the invention are more apparent from the detailed description which follows, with reference to the accompanying drawings which illustrate a preferred embodiment of the invention purely by way of non-limiting example, and in which:

[0078] - Figure 1 shows a perspective view of a wheel rim in a first configuration, according to this disclosure;

[0079] - Figure 2 shows a perspective view of a wheel rim in a second configuration, according to this disclosure;

[0080] - Figure 3 shows a perspective view of a wheel rim in a first configuration, according to this disclosure;

[0081] - Figure 4 shows a detail from Figure 3, according to this disclosure.

[0082] Detailed description of preferred embodiments of the invention

[0083] With reference to the accompanying drawings, and in particular Figure 1, the numeral 1 denotes a vehicle wheel rim.

[0084] In particular, the disclosure relates to a wheel rim for a sports car, preferably an electric vehicle.

[0085] The wheel rim 1 comprises a main body 2 which comprises a peripheral bead seat 3, a centre flange 4 and a centre portion 5 for connecting the peripheral bead seat 3 to the centre flange 4.

[0086] The peripheral bead seat 3 defines in the rim a groove for seating a vehicle tyre.

[0087] The centre flange 4 allows coupling the rim 1 to a vehicle wheel hub.

[0088] The centre portion 5 has at least one opening 7 to allow air to flow through it.

[0089] In an embodiment, the centre portion 5 comprises a plurality of spokes 6.

[0090] The spokes 6 extend between the peripheral bead seat 3 and the centre flange 4.

[0091] As illustrated in Figure 2, an opening 7 is defined between every two spokes 6.

[0092] Preferably, the centre portion 5 thus has a plurality of openings 7.

[0093] The rim 1 comprises at least one panel 8 associated with the opening 7.

[0094] The panel 8 is movable between a closed position Pl and an open position P2.

[0095] At the closed position Pl, the panel 8 closes at least part of the opening 7 thereby obstructing an air flow through the opening 7.

[0096] At the open position P2, the panel 8 is positioned so that the opening 7 is accessible and allows the air to flow through it.

[0097] The rim 1 comprises a drive unit 9.

[0098] As illustrated in Figures 3 and 4, the drive unit 9 is coupled to the panel 8.

[0099] The drive unit 9 is configured to move the panel 8 between the closed position Pl and the open position P2 as a function of a temperature variation in the drive unit 9 itself.

[0100] In a preferred embodiment, the panel 8 is movable between the open position P2 and the closed position Pl by rotation.

[0101] In an embodiment, the drive unit 9 comprises an actuator 10.

[0102] The actuator 10 is made of a shape memory alloy.

[0103] Shape memory materials are metallic materials which, after being deformed, have the ability of returning to their original shape when subjected to specific thermal conditions.

[0104] The actuator 10 is configured to vary its length as a function of the temperature variation in the drive unit 9.

[0105] For example, activation of the brake system of the vehicle causes the drive unit 9 and the actuator 10 to heat up.

[0106] Preferably, as illustrated in Figure 4, the actuator 10 has a spring structure.

[0107] The actuator 10 has, along a direction D, a first length when the panel 8 is at the closed position Pl, and a second length when the panel 8 is at the open position P2.

[0108] The actuator 10 is configured to exert a predetermined force as a result of the variation in its length.

[0109] The drive unit 9 comprises a transmission apparatus 11 adapted to transmit said force from the actuator 10 to the panel 8 to move it between the closed position Pl and the open position P2.

[0110] Preferably, the transmission apparatus 11 is configured to move the panel 8 to intermediate positions between the closed position Pl and the open position P2.

[0111] In particular, the transmission apparatus 11 is configured to move the panel 8 to intermediate positions between the closed position Pl and the open position P2 as a function of the variation in the length of the actuator 10.

[0112] As a result of the variation in its length, the actuator 10 is thus configured to exert a predetermined force on the transmission apparatus 11.

[0113] The actuator 10 has a respective first end 10A, fixed to the centre portion 5 and a second end 10B fixed to the transmission apparatus 11.

[0114] In an embodiment, the actuator 10 has its respective first end 10A fixed to a first spoke 6 of the pair of spokes 6 that define the air flow opening 7.

[0115] The transmission apparatus 11 is configured to rotate the panel 8 between the open position P2 and the closed position Pl.

[0116] Preferably, the drive unit 9 comprises an elastic opposing element 12 coupled to the transmission apparatus 11.

[0117] The elastic opposing element 12 is configured to oppose the force exerted by the actuator 10.

[0118] The elastic opposing element 12 has a respective first end 12A fixed to the centre portion 5 and a respective second end 12B fixed to the transmission apparatus 11 on the opposite side with respect to the second end 10B of the actuator 10.

[0119] In a preferred embodiment, the transmission apparatus 11 comprises a transmission element 13.

[0120] The transmission element 13 is interposed between the actuator 10 and the opposing element 12.

[0121] In particular, the end 10B of the actuator 10 is joined to the transmission element 13, and the end 12B of the opposing element 12 is joined to the transmission element 13.

[0122] The actuator 10 is configured to move the transmission element 13 between a first position, where the panel 8 is at the open position P2, and a second position, where the panel 8 is at the closed position Pl.

[0123] The transmission element 10 allows force to be transferred between the actuator 10 and the opposing element 12.

[0124] In a preferred embodiment, the transmission apparatus 11 comprises a rod 14 having a first end 14A and a second end 14B, both fixed to the panel 8.

[0125] In an embodiment, the elastic element 14 has its respective first end 14A fixed to a second spoke 6 of the pair of spokes 6 that define the air flow opening 7.

[0126] The rod 14 is coupled to the actuator 10 by the transmission element 11.

[0127] The transmission element 11 is configured to rotate the rod 14 about an axis A14.

[0128] The first end 14A of the rod is fixed to the panel 8 by a first connecting element15A and the second end 14B of the rod is fixed to the panel 8 by a second connecting element 15B.

[0129] Also an object of this disclosure is a method for improving the energy efficiency of a wheel rim.

[0130] The method comprises providing a wheel rim 1 comprising a main body 2 comprising the peripheral bead seat 3, which defines in the rim a groove for seating a vehicle tyre, a centre flange 4 for coupling the rim to a vehicle wheel hub and a centre portion 5 extending between the peripheral bead seat 3 and the centre flange 4.

[0131] The centre portion 5 has at least one opening 7 to allow air to flow through it, and the wheel rim comprises at least one panel 8 which is coupled to the opening 7.

[0132] The method comprises moving the panel 8, as a function of a temperature variation, between a closed position Pl, where it closes at least part of the opening 7, thereby obstructing the air flow, and an open position P2, where the opening 7 is accessible and allows the air to flow through it.

[0133] In an embodiment, the method comprises moving the panel 8 from the closed position Pl to the open position P2 as a result of a rise in the temperature.

[0134] In an embodiment, the method comprises moving the panel 8 from the open position P2 to the closed position Pl as a result of a drop in the temperature.

[0135] In an embodiment, the method comprises moving the panel 8 between the closed position Pl and the open position P2 by means of a drive unit 9 which comprises an actuator 10 made of a shape-memory alloy.

Claims

Claims

1. A vehicle wheel rim, said rim comprising:- a main body (2) comprising a peripheral bead seat (3), defining in the rim a groove for seating a vehicle tyre, a centre flange (4) for coupling the rim to a vehicle wheel hub and a centre portion (5) for connecting the peripheral bead seat (3) to the centre flange (4), the centre portion (5) having at least one air flow opening (7),- at least one panel (8), coupled to the opening (7), movable between a closed position (Pl), where it closes at least part of said opening (7) thereby obstructing an air flow through the opening, and an open position (P2), where said opening (7) is accessible and allows the air to flow through,- a drive unit (9), coupled to the panel (8) and configured to move said panel (8) between the closed position (Pl) and the open position (P2) as a function of a temperature variation in the drive unit (9), the drive unit (9) comprising an actuator (10), made of a shape memory alloy, configured to vary its length as a function of the temperature variation and to exert a predetermined force, the drive unit (9) comprising a transmission apparatus (11) adapted to transmit said force from the actuator (10) to said panel (8) to move it between the closed position (Pl) and the open position (P2), the actuator (10) having a respective first end (10A), fixed to the centre portion (5) and a second end (10B) fixed to the transmission apparatus (11).

2. The rim according to claim 1, wherein the transmission apparatus(11) is configured to move the panel (8) to intermediate positions between the closed position (Pl) and the open position (P2).

3. The rim according to any one of the preceding claims, wherein the panel (8) is movable by rotation between the open position (Pl) and the closed position (P2), the transmission apparatus (11) being configured to rotate said panel between the open position and the closed position.

4. The rim according to any one of the preceding claims, wherein the drive unit (9) comprises an elastic opposing element (12), coupledto the transmission apparatus (11) and configured to oppose the force exerted by the actuator (10).

5. The rim according to claim 4, wherein the elastic opposing element (12) has a respective first end (12A) fixed to the centre portion (5) and a respective second end (12B) fixed to the transmission apparatus (11) on the opposite side with respect to the second end (10B) of the actuator (10).

6. The rim according to any one of the preceding claims, wherein the actuator (10) has, along a direction (D), a first length when the panel (8) is at the closed position (Pl), and a second length when the panel (8) is at the open position (P2).

7. The rim according to any one of the preceding claims, wherein said actuator (10) has a spring structure.

8. The rim according to any one of the preceding claims, wherein said transmission apparatus (11) comprises a transmission element (13), said actuator (10) being configured to move said transmission element (13) between a first position, where the panel (8) is at the open position (P2), and a second position, where the panel (8) is at the closed position (Pl).

9. The rim according to claim 8, wherein the transmission apparatus(11) comprises a rod (14) having a first end (14A) and a second end (14B), both fixed to the panel (8), said rod (14) being coupled to the actuator (10) by the transmission element (13), the transmission element (13) being configured to rotate said rod (14) about an axis (A 14).

10. The rim according to claim 9, wherein the first end (14A) of the rod (14) is fixed to the panel (8) by a first connecting element (15A) and the second end (14B) of the rod is fixed to the panel (8) by a second connecting element (15B).

11. The rim according to any one of the preceding claims, wherein the centre portion (5) comprises a plurality of spokes (6) extending between the peripheral bead seat (3) and the centre flange (4), each pair of spokes (6) defining an air flow opening (7).

12. The rim according to claim 11, wherein the actuator (10) has its respective first end (10A) fixed to a first spoke (6) of the pair of spokes (6) that define the air flow opening (7).

13. The rim according to claims 12 and 5, wherein the elastic element(12) has its respective first end (12A) fixed to a second spoke (6) of the pair of spokes (6) that define the air flow opening (7).

14. A method for improving the energy efficiency of a vehicle wheel rim, comprising:- providing a rim (1) comprising a main body (2) comprising a peripheral bead seat (3), defining in the rim (1) a groove for seating a vehicle tyre, a centre flange (4) for coupling the rim (1) to a vehicle wheel hub and a centre portion (5) for connecting the peripheral bead seat (3) to the centre flange (4), the centre portion (5) having at least one air flow opening (7), and the rim (1) comprising at least one panel (8) coupled to the opening (7),- moving the panel (8), as a function of a temperature variation, between a closed position (Pl), where it closes at least part of said opening (7), thereby obstructing the air flow, and an open position (P2), where said opening (7) is accessible and allows the air to flow through it.

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