Vehicle wheel provided with an assembly carried by a wheel rim for adjusting the air pressure

Abstract

A vehicle wheel (1) has a rim (3), a tyre (4) defining an air chamber (5) together with the rim (3), and an assembly (20) for adjusting the air pressure in this chamber (5); the assembly (20) is provided with at least one compressor (21) 5 pneumatically connected to the chamber (5), and at least one reservoir (22) pneumatically connected to the compressor (21) to receive compressed air; the compressor (21) and the reservoir (22) are housed in respective compartments (30) that are defined by respective spokes (13) of the rim (3).

Description

[0001] "VEHICLE WHEEL PROVIDED WITH AN ASSEMBLY CARRIED BY A WHEEL

[0002] RIM FOR ADJUSTING THE AIR PRESSURE"

[0003] Cross-Reference to Related Applications

[0004] This Patent Appl ication claims priority from Italian Patent Application No . 102023000027819 filed on December 22 , 2023 , the entire disclosure of which is incorporated herein by reference .

[0005] Technical field

[0006] This invention relates to a vehicle wheel provided with an assembly for adj usting the air pressure inside its tyre , and this assembly is carried by the wheel rim .

[0007] In particular, this assembly includes a motorised compressor, driven to trans fer air into one or more reservoirs , while adj ustment valves manage air flows from the reservoirs to the air chamber in the tyre and from such air chamber to the compressor .

[0008] Background

[0009] In order to adj ust the internal pressure in tyres , solutions are known with a centralised on-vehicle architecture , which has a single reservoir and a single compressor, controlled by an appropriate control unit so as to be activated and feed compressed air into this reservoir . The reservoir is then connected to the wheels via respective conduits fitted with valves , which are also controlled by the above-mentioned control unit to adj ust the flow of compressed air : these valves are switched to inflate the tyre or discharge air from it towards the outside environment .

[0010] In addition, another valve pneumatically connects the compressor to the reservoir so that the two components can be isolated when required .

[0011] Compared to this type of centralised solution, it is preferable to adopt inflation and deflation systems that are arranged directly on the wheel , to reduce the number of components , reduce the space required on board the vehicle , and avoid passages of compressed air between a fixed part , i . e . the vehicle body, and a rotating part , i . e . the wheel .

[0012] In the context of these decentralised solutions , document EP0621144 discloses an example where a two-way compressor is provided on the wheel , which trans fers air between the air chamber in the tyre and an additional annular chamber, integrated in the wheel rim and defining a reservoir for storing air .

[0013] Another example disclosed by EP0621144 , namely the one in Figure 2 , involves the use of a one-way compressor and an additional pneumatic line , which connects the tyre air chamber with the rim integrated annular reservoir, in parallel with the compressor . A valve then manages the passage of air through this line to inflate the tyre .

[0014] In both these solutions , to adj ust the pressure in the tyre , air is exchanged between the air chamber and the reservoir integrated into the rim, without contamination by external air .

[0015] There is a need to refine this type of solution, especially with regard to the simpli fication of the rim structure where the air storage reservoir is located .

[0016] In particular, there is a need to find a solution that is relatively compact but does not negatively af fect the design and construction of the rim .

[0017] More speci fically, it is preferable to adopt a solution that is relatively easy to assemble , with a small number of components , and does not negatively af fect the aesthetic value of the rim .

[0018] In addition, it is preferable to adopt a solution in which the various components of the system for adj usting the pressure are arranged outside the tyre air chamber, for safety reasons .

[0019] One purpose of this invention is that of meeting the needs described above , preferably in a simple and / or ef fective and / or cost-ef fective way .

[0020] Summary

[0021] The above-mentioned purpose is achieved with a vehicle wheel as defined in claim 1 .

[0022] The dependent claims define particular embodiments of the invention . Brief Description of the Drawings

[0023] For a better understanding of this invention, preferred embodiments will be described below, by way of non-limiting example, with reference to the accompanying drawings, wherein :

[0024] Figure 1 illustrates, in front perspective, a vehicle wheel according to a preferred embodiment of this invention;

[0025] Figure 2 is a rear view of the wheel in Figure 1, with parts removed for clarity;

[0026] Figure 3 shows a detail of Figure 2 from a different viewpoint and on an enlarged scale;

[0027] Figure 4 is an enlarged view of a detail in Figure 3, from a different viewpoint;

[0028] Figure 5 illustrates some wheel components of the previous figures; and

[0029] Figure 6 is a simplified cross section obtained from a sectional plane on which the wheel axis lies.

[0030] Description of Embodiments

[0031] In Figure 1, reference number 1 indicates, as a whole, a vehicle wheel, which is partially illustrated.

[0032] The wheel 1 has an axis 2, coinciding, in use, with its rotation axis, and comprises a rim 3 and a tyre 4 (illustrated in dotted lines) , fitted on the rim 3 in such a way as to define, together with the latter, a chamber 5 that is filled with air and can be pressuri zed from the outside through a valve 6 . The valve 6 , a known type , is brought to a relative fixed position by the rim 3 .

[0033] In particular, the rim 3 has an outer annular wall 7 , which radially delimits the chamber 5 and is shaped to include an intermediate portion 8 and two shoulders 9 arranged at oppos ite axial ends of the rim 3 . These shoulders 9 protrude radially outwards from the intermediate portion 8 ; furthermore , at the shoulders 9 , the wall 7 defines two concave areas that are shaped so as to couple the tyre 4 beads , in a sealed manner, according to shapes and techniques that are known and not shown in detail .

[0034] The rim 3 comprises a central hub 12 and a plurality of spokes 13 j oining the central hub 12 to the outer annular wall 7 and, preferably, extending radially with respect to the axis 2 .

[0035] As shown in Figure 2 , the wheel 1 further comprises an assembly 20 for adj usting the pressure in the chamber 5 automatically, for example to keep it within a predetermined setpoint range , and / or to keep it as close as possible to a predetermined setpoint value , during use ( i . e . during vehicle travel ) .

[0036] The assembly 20 is carried by the rim 3 , on the wheel 1 , and therefore rotates together with the rim 3 around the axis 2 during use . As can be seen in detail in Figure 3 , the assembly 20 comprises at least one motorised compressor 21 , at least one reservoir 22 defining, within it , a chamber with a substantially fixed volume , separated from the chamber 5 and the external environment ; and at least one battery 22a ( shown in exploded view in Figure 4 ) for supplying electricity to the electric motor of the compressor 21 . In the preferred example shown, the battery 22a is carried by the same compressor 21 .

[0037] As shown in Figure 5 , the compressor 21 has an inlet port designed to communicate with the chamber 5 via a conduit 23 that passes through the wall 7 in such a way as to still ensure the fluid tightness of the chamber 5 . The configuration of the reservoir 22 is similar : the reservoir 22 has an outlet port des igned to communicate with the chamber 5 via a conduit 24 that passes through the wall 7 in such a way as to ensure the fluid tightness of the chamber 5 .

[0038] The assembly 20 also comprises a microprocessor 25 , which controls the electric motor of the compressor 21 in response to command signals emitted wirelessly by an emitter (not illustrated) placed in a fixed position on board the vehicle , and / or in response to operations performed by a control strategy stored in a memory forming part of the same microprocessor 25 . In the speci fic example shown, the microprocessor 25 is brought to a fixed position by the compressor 21 .

[0039] This architecture is therefore decentralised, as the assembly 20 is mounted on each of the wheels of the vehicle and has no pneumatic and / or electrical connections to the fixed parts of the vehicle .

[0040] More speci fically, the microprocessor 25 is configured to drive the compressor 21 motor and then activate the latter, e . g . in response to a control signal and / or a reference signal ( setpoint ) provided by the vehicle instrument panel , to send pressurised air from the chamber 5 to the reservoir 22 , but not vice versa .

[0041] According to a preferred aspect of this invention, in fact , the compressor 21 is one-way, i . e . it is constructed and assembled in such a way that it can only convey a flow of air in one direction ( from the chamber 5 to the reservoir 22 ) .

[0042] In particular, a valve or solenoid valve 26 is interposed between the chamber 5 and the inlet port of the compressor 21 , to prevent air leakage from the chamber 5 when the compressor 21 is switched of f . Alternatively, the valve 26 is integrated into the inlet port of the compressor 21 .

[0043] The assembly 20 also includes a solenoid valve 27 , which is arranged along the conduit 24 and switches in response to an electric command, sent by the microprocessor 25 in a not illustrated way, between

[0044] - a closed configuration, in which the reservoir 22 is pneumatically isolated from the chamber 5 , and

[0045] - an open configuration, to allow a flow of air from the reservoir 22 to the chamber 5 ( i . e . a flow in the opposite direction to that imposed by the compressor 21 ) .

[0046] The microprocessor 25 is preferably configured to also check the temperature of the air inside the chamber 5 , by at least one temperature sensor (not illustrated) , connected wirelessly or wired to communicate with the same microprocessor 25 , for a possible correction of the pressure of the air to be introduced / discharged and / or a possible correction of the setpoint values , depending on the temperature detected .

[0047] In addition, the microprocessor 25 is connected, wirelessly or wired, to communicate with at least one pressure sensor mounted on the wheel 1 and designed to detect the pressure in the chamber 5 . The pressure sensor can be of a known type , usually referred to as a TPMS . In other words , the microprocessor 25 interacts with this sensor to receive readings of the pressure values inside the chamber 5 .

[0048] The temperature and / or pressure sensors are usually installed at the valve 6 .

[0049] The control logics implemented in the microprocessor 25, and / or the control signals coming from a fixed control unit, on board the vehicle, are configured in such a way as to inflate and deflate the chamber 5, i.e. to adjust the air pressure inside it, preferably with such quantities / pressures of air that optimise adherence to the ground during use, depending also on the type of ground or according to a driver's command that is indicative of this type (e.g. on mud or sand the pressure should be reduced, while on asphalt the pressure should be higher to reduce rolling resistance) .

[0050] As mentioned above, the air in the chamber 5, previously supplied from outside through the valve 6, is pumped by the compressor 21 and transferred to the reservoir 22 in order to reduce the pressure, i.e. to deflate the tyre 4.

[0051] Similarly, by controlling the solenoid valve 27 that is placed at the outlet of the tank 22 (between the latter and the chamber 5) , a flow of air is allowed from the same reservoir 22 (at a higher pressure) to the chamber 5 (at a lower pressure) , and thus the pressure in the chamber 5 increases: in other words, the tyre 4 is inflated.

[0052] The microprocessor 25 is preferably configured with appropriate control logics to carry out diagnostics of the entire assembly 20 and then transmit information relating to any malfunctions and / or information relating to adjustment and stand-by steps between two successive adjustments to an on-board control unit ( and then to the instrument panel in the passenger compartment ) .

[0053] The assembly 20 also includes a system (not shown) for recharging electricity in the battery 22a . In particular, such a system is of the induction type and / or is arranged at an external surface of the wheel 1 to be coupled to the mains power supply, or to a vehicle power supply device ( e . g . a cigarette lighter device ) , only when the vehicle is stationary . Other charging systems can still be envisaged, for example by using the very rotation of the wheel 1 to generate power for the battery 22a .

[0054] During deflation, the pressure in the reservoir 22 increases more than the pressure in the chamber 5 decreases , with the same amount of air entering and respectively leaving, because the volumes in the reservoir 22 are smaller than in the chamber 5 , and the pressure in the reservoir 22 is much higher than that in the chamber 5 .

[0055] During inflation, by operating the solenoid valve 27 , the compressor 21 remains deactivated and the pressure in the reservoir 22 decreases .

[0056] With reference to Figures 3 and 4 , according to this invention, the compressor 21 and the reservoir 22 are behind the spokes 13 of the rim 3 , and thus in use are hidden from view by those spokes 13 .

[0057] In other words , each spoke 13 is bordered by a front surface 30 ( Figure 1 ) , which is arranged, in use , along the side of the vehicle and faces outwards , and by a rear surface 31 ( Figures 3 and 4 ) , which is opposite the front surface 30 and actually covers the compressor 21 and tanks 22 of the assembly 20 . In particular, the compressor 21 and reservoirs 22 are arranged in positions directly facing the rear surfaces 31 of the spokes 13 . More speci fically, the rear surface 31 of the spokes 13 performs a support function to fix the compressor 21 and tanks 22 , as will also be described below .

[0058] In particular, the compressor 21 and the reservoir 22 are configured to extend along respective axes 32 that are parallel to the radial directions in which the spokes 13 extend .

[0059] The compressor 21 and the reservoir 22 are preferably partially housed in respective recesses 33 , which are defined by the rear surfaces 31 . Therefore , the compressor 21 and reservoirs 22 partially protrude axially beyond the rear surface 31 , improving the compactness of the proposed solution . In particular, the recesses 33 extend substantially along the entire radial length of the spokes 13 .

[0060] In general , the rim 3 does not require any additional cover to conceal or cover the components of the assembly 20 .

[0061] As shown in Figures 3 and 5 , the attachment of the compressor 21 and reservoir 22 to the spokes 13 of the rim 3 preferably involves one or more screw or bolt couplings , identi fied by the reference number 36 . However, other fastening methods could be used . In particular, as shown in Figure 4 , a fastener 37 may be mounted astride the compressor 21 and / or reservoir 22 and in such a way as to snap-couple the ends 38 of the same fastener 37 to the edges of the corresponding spoke 13 , in order to provide a spring thrust directed towards the corresponding rear surface 31 .

[0062] With reference to Figure 6 , preferably a plug of damping material 39 is placed between the compressor 21 and the rear surface 31 to dampen vibrations during use . It is clear that the compression of the plug 39 opposes the elastic thrust exerted by the fastener 37 . Similarly, a plug of damping material can also be provided between the reservoir 22 and the corresponding rear surface 31 .

[0063] As shown in Figures 3 and 5 , the compressor 21 has a delivery port that communicates with the reservoir 22 via a conduit 40 that extends , at least in part , at the central hub 12 . The conduit 40 is arranged behind the spokes 13 and the central hub 12 , i . e . on the side of the rear surface 31 . In particular, one or more fasteners 41 are provided to hold the conduit 40 in a fixed position relative to the rear surface of the central hub 12 .

[0064] As mentioned above , the assembly 20 preferably comprises more than one reservoir 22 , each arranged behind a respective spoke 13 , separately from the others . In this preferred configuration, shown in the attached figures , the conduit 40 connects all the reservoirs 22 simultaneously with the delivery port of the compressor 21 , so it also performs a distributor function from the delivery port towards all the reservoirs 22 . In particular, the conduit 40 consists of several separate pipes , but could also be envisaged in the form of a continuous loop, e . g . in the form of a circle .

[0065] It is clear from the above that the proposed arrangement for the compressor 21 and reservoirs 22 allows the use of spokes 13 to support the assembly 20 and, at the same time , to protect these components from external agents or shocks .

[0066] Furthermore , the fact of having to install the assembly 20 on the wheel 1 does not negatively af fect the design of the structure of the wall 7 and spokes 13 , and / or the safety conditions during driving, since the various components (with the possible exception of the solenoid valves 26 and / or 27 ) are arranged outside the chamber 5 .

[0067] In terms of design and construction, the wall 7 only needs to be drilled for the passage of the conduits 23 and 24 . At the same time , the spokes 13 are af fected by marginal modi fications , compared to the known standard rim solutions , which are only necessary to be able to mount and support the components of the assembly 20 .

[0068] The conduits 23 , 24 and 40 , which connect the components to each other or to the internal cavity of the tyre 4 , are preferably coupled during assembly by quick coupling systems (not illustrated) , for ease of assembly and / or disassembly of the assembly 20 on the wheel 1 .

[0069] Furthermore , as mentioned above , the proposed solution allows for a simple solution with a relatively smal l number of components , as it does not require covers or other additional protective elements to be placed over the components of the assembly 20 , since the spokes 13 are used to cover and protect these components .

[0070] Other advantages are also clear to a person skilled in the art based on what is described above and what is illustrated in the attached figures .

[0071] Lastly it is clear that modi fications and variations may be made to the wheel 1 according to this invention without departing from the scope of protection defined by the attached claims .

[0072] In particular, the manner in which the components of the assembly 20 are coupled to the rim 3 may be di f ferent from those shown as examples .

[0073] Furthermore , the manner in which air is trans ferred from the reservoir 22 to the chamber 5 during inflation of the wheel 1 could take place in a di f ferent manner, for example by exploiting the passage defined by the compressor 21 itsel f ( and thus excluding the presence of the solenoid valve 27 and the conduit 24 ) .

Claims

CLAIMS1.- A vehicle wheel (1) extending along a central axis(2) and comprising:- a rim (3) comprising an outer annular wall (7) , a hub (12) , and a plurality of spokes (13) extending from said hub (12) to said outer annular wall (7) ,- a tyre (4) defining, together with said outer annular wall (7) , a chamber (5) which is filled with air and can be pressurized;- an assembly (20) for adjusting the air pressure in said chamber (5) , the assembly comprising: a) at least one compressor (21) having:(1) an inlet port suitable to be pneumatically connected to said chamber (5) , and(2) a delivery port; b) at least one reservoir (22) pneumatically connected to said delivery port for receiving compressed air from said compressor (21) and suitable to be pneumatically connected to said chamber (5) for transferring air to said chamber (5) ; characterized in that said reservoir (22) and said compressor (21) are arranged respectively behind a rear surface (31) of said spokes (13) so as to be covered by said spokes (13) .2.- The vehicle wheel according to claim 1, wherein said reservoir (22) and said compressor (21) are supported infixed positions by said spokes (13) .3.- The vehicle wheel according to claim 2, wherein said reservoir (22) and said compressor (21) are fixed to said rear surface (31) . 4.- The vehicle wheel according to any one of the preceding claims, wherein said reservoir (22) and said compressor (21) are partially housed in respective recesses (33) , defined by the rear surfaces (31) of said spokes (13) .5.- The vehicle wheel according to any one of the preceding claims, wherein said assembly comprises a plurality of reservoirs, each arranged behind a respective one of said spokes (13) and communicating with the other reservoirs and with the delivery port of said compressor (21) via a conduit (40) .

Images