The present invention relates to a wheel for a tubeless tyre and intended to be mounted on a vehicle, particularly on a motor vehicle.

An object of the present invention is to implement a wheel for tubeless tyres of an innovative type.

This object and others are achieved according to the present invention by a wheel, the primary characteristics of which are defined in the annexed claim 1.

Further characteristics and advantages of the present invention will be clearly understood from the following detailed description, given purely by way of non- limiting example, with reference to the annexed drawings, in which:

Figure 1 is a partial sectional view (through an axial plane) of an exemplary embodiment of a wheel according to the present invention;

Figure 2 is a partial sectional view (through a radial plane) of the wheel illustrated in Figure 1 ;

Figure 2a is a schematic view from the arrangement of first (or second) holes located on the development of the lateral surface of a disc (or rim) first (or second) assembling region;

Figure 3 is a detailed view of a fixing device associated to the disc and rim of the wheel shown in Figure 2; and

Figure 4 is a longitudinally sectioned view of a connecting element of the fixing device shown in Figure 3.

With reference particularly to Figure 1, there is shown a preferred embodiment of a wheel 10 according to the present invention, and the rotational axis of which is indicated by the line X-X. By the term "axial" in the description and the claims of the present invention, reference is made to a direction parallel to the rotational axis X-X of the wheel 10.

By the term "radial" in the description and the claims of the present invention, reference is made to a direction perpendicular to the wheel 10 rotational axis X-X and passing through such rotational axis X-X.

By the term "transversal" in the description and the claims of the present invention, reference is made to a direction defined by a straight line intersecting in one point the rotational axis X-X.

By the term "circumferential" in the description and the claims of the present invention, reference is made to a region located on a circumference having the centre thereof lying in the rotational axis X-X of the wheel 10.

With reference particularly to Figure 1, there is illustrated a preferred embodiment of a wheel 10 according to the present invention, and the rotational axis of which is indicated by the line X-X.

The wheel 10 is intended for the use with a tubeless tyre (not shown) and to be mounted on a vehicle. In particular, the intended use of such wheel 10 is on a motor vehicle.

The wheel 10 comprises a disc 12, a rim or channel portion 14, and a plurality of fixing devices 16 connecting therebetween said disc 12 and rim 14.

The disc 12 is intended to be connected in the axial direction to a vehicle hub (details are not shown). In the embodiment illustrated, the disc 12 optionally has a plurality of radially outer openings 18 and a central opening 20, around which a plurality of holes 22 are obtained, by means of which the connection to the vehicle hub can take place. Furthermore, the radially outer end of the disc 12 has a first assembling portion 24 circumferentially arranged, and which is axially inwardly reversed. Preferably, the first assembling portion 24 has a plurality of first holes 26 which are circumferentially mutually spaced apart. The first holes 26 are through- holes, and advantageously have a circular-shaped section. As seen in Figure 3, radially moving from the outer part to the inner part with respect to the rotational axis X-X ₅ preferably such first holes 26 have an enlarged diameter initial part 27, and a reduced diameter end part 29. According to an alternative embodiment variation, the first holes 26 may also be blind at the end part 29.

The channel portion 14 is intended to be connected to a tubeless tyre (not shown) in a radial direction. In the illustrated embodiment, the channel 14 has a pair of circumferential flanges 28 which are located at the axial ends of such channel portion 14, and which are radially extending outwardly. The flanges 28 define a pair of seats 30 suitable to house the respective beads of the tubeless tyre (not shown), which is intended to be coupled to the wheel 10. Preferably, the channel portion 14 has a second circumferentially arranged assembling portion 32 which has a plurality of second holes 34 which are through-holes, and circumferentially mutually spaced apart. Such second assembling portion 32 is advantageously located in a zone which is radially inner than the channel portion 14 and which is axially arranged between the pair of seats 30. Preferably, the second assembling portion 32 is brought near to the seat 30, which is located in an axially outer portion. Advantageously, the second holes 34 have a circular-shaped section. As seen in Figure 3, radially moving from the outer part to inner part with respect to the rotational axis X-X ₅ the second holes 34 preferably have an enlarged diameter initial section 37 and a reduced diameter end section 39.

In the illustrated embodiment, the fixing devices 16 preferably comprise a connecting element 36 and a sealing member 38. According to what has been illustrated in Figures 3 and 4, the connecting element 36 has a substantially circular section, and preferably comprises an enlarged head or portion 40 having a maximum diameter, a middle portion 42 having an intermediate diameter, and an end portion 44 having a reduced diameter and an outer thread. Suitably, the enlarged head has an annular groove 48 (Figure 4) which separates the head 40 from the middle portion 42 of the connecting element 36.

The sealing member 38 is preferably a seal ring (also referred to as "O-ring") which is housed in the annular groove 48 of the connecting element 36.

As better seen in Figures 2 and 3, advantageously the first holes 26 are coaxial with the second holes 34 according to respective transversal directions relative to the rotational axis X-X. More preferably, the first holes 26 and the second holes 36 are mutually coaxial according to respective radial directions relative to the rotational axis X-X. The coupling of each of the first holes 26 with a respective second hole 34 takes place due to a respective securing device 16. More precisely, each connecting element 36 passes through a respective first hole 26 and a respective second hole 34, and contributes to mechanically couple the disc 12 and the rim 14.

Particularly, the initial section 37 of each second hole 34 accommodates the connecting element respective enlarged head 40. The end section 39 of each second hole 34, and- the initial portion 27 of the respective first hole 26 have the same diameter, and accommodate the respective connecting element 36 middle portion 42. The terminal portion 29 engages the inner thread thereof with the outer thread of the end portion 44 of the respective connecting element 36. As it shall be apparent to those of ordinary skill in the art, it can be devised to change the threaded coupling arrangement, which is obtained by way of the outer groove of the connecting element 36. In fact, alternatively, the externally grooved section can be replicated, for example, in the connecting element 36 middle portion 42. Furthermore, the inner thread which is complementary to the externally threaded portion of the connecting element 36 can be obtained in the respective second hole 34, rather than in the respective first hole 26. According to a further optional variation, the first hole 26 and the second hole 34 can be threaded along all the extension thereof.

Each sealing member 38 housed in the annular groove 48 ensures the fluid- tight sealing coupling between disc 12 and rim 14 through the first holes 26 and the second holes 34, avoiding that leakages of fluid from the tyre may occur. Particularly, each sealing member 38 seals the respective first hole 26 in which it is clamped between the respective enlarged head 40 of the associated connecting element 36 and the rim 14. In fact, as shown in Figure 3, when a tubeless tyre (not shown) is mounted on the wheel 10, the air contained therein tends to radially push the enlarged head 40 towards the inner part with respect of the rotational axis X-X, according to the arrows shown. Consequently, the enlarged head 40 tends to compress the sealing member 38, thus clamping it against the rim 14.

In this manner, a transversal (preferably radial) connection is obtained between disc 12 and rim 14, and which at the same time is fluid-tight.

According to an embodiment variation of the connecting element 36, the externally grooved length thereof can be of the self-drilling type, therefore the inner thread of the second hole 34 (and/or, optionally, the first hole 26) can be omitted.

Advantageously, as it may also be realized from Figure 1, in order to improve the load distribution in the structure of the wheel 10, in the first assembling region 24 each of the first holes 26 is axially offset relative to the preceding one. In this manner, as it shall be fully appreciated in the schematic view illustrated in Figure 2a, the first assembling holes 26 are arranged according to a first circumferential arrangement 26a and a second circumferential arrangement 26b which are mutually parallel and axially spaced apart, in order to obtains the above-mentioned axial offsetting. In this case, the same arrangement is clearly replicated for the second holes 34 in the second assembling region 32.

Naturally, the principle of the invention remaining the same, the embodiments and the constructional details may be widely varied with respect to what has been described and illustrated purely by way of a non-limiting example, without thereby departing from the scope of the invention as defined in the annexed claims.