GB2553370A

GB2553370A - A noise-reducing device for a vehicle

Info

Publication number: GB2553370A
Application number: GB1615111.0A
Authority: GB
Inventors: Nourzad Delphnine; Bees David; Dodu Maelle; Slater Barry; Parsons Bill
Original assignee: Jaguar Land Rover Ltd
Current assignee: Jaguar Land Rover Ltd
Priority date: 2016-09-06
Filing date: 2016-09-06
Publication date: 2018-03-07
Also published as: GB201615111D0

Abstract

A noise-reducing device 10 for a vehicle wheel (40, see fig 4) comprises at least one element 12 arranged to be secured around a region of the wheel that is configured to form part of a tyre cavity; at least one cavity 18 formed in the at least one element, the or each cavity having an opening 70 to provide communication between the or each cavity and the tyre cavity; and at least one fastening member (54, see fig 3) arranged to secure the at least one element around a region of the wheel; wherein the or each cavity is arranged to define at least in part a chamber that acts as a Helmholtz resonator when the device is installed onto the wheel; and the at least one cavity has a width substantially corresponding to the width of the or each element. The device may comprise at least two elements. The fastening device may encircle the or each element and may apply inward radial force to press the or each element on the wheel. The wheel may also comprise an upstand (45) arranged to provide an abutment surface for the device.

Description

(71) Applicant(s):

Jaguar Land Rover Limited (Incorporated in the United Kingdom)

Abbey Road, Whitley, Coventry, Warwickshire, CV3 4LF, United Kingdom (72) Inventor(s):

Delphnine Nourzad David Bees Maelle Dodu Barry Slater Bill Parsons (74) Agent and/or Address for Service:

JAGUAR LAND ROVER

Patents Department W/1/073, Abbey Road, Whitley, Coventry, Warwickshire, CV3 4LF, United Kingdom (56) Documents Cited:

EP 2783879 A1 WO 2005/021291 A1 JP 2015067051 A JP 2004148978 A (58) Field of Search:

INT CL B60B, B60C Other: EPODOC, WPI

EP 1698494 A1 WO 2001/023195 A1 JP 2009214613 A (54) Title of the Invention: A noise-reducing device for a vehicle Abstract Title: A noise-reducing device for a vehicle tire (57) A noise-reducing device 10 for a vehicle wheel (40, see fig 4) comprises at least one element 12 arranged to be secured around a region of the wheel that is configured to form part of a tyre cavity; at least one cavity 18 formed in the at least one element, the or each cavity having an opening 70 to provide communication between the or each cavity and the tyre cavity; and at least one fastening member (54, see fig 3) arranged to secure the at least one element around a region of the wheel; wherein the or each cavity is arranged to define at least in part a chamber that acts as a Helmholtz resonator when the device is installed onto the wheel; and the at least one cavity has a width substantially corresponding to the width of the or each element. The device may comprise at least two elements. The fastening device may encircle the or each element and may apply inward radial force to press the or each element on the wheel. The wheel may also comprise an upstand (45) arranged to provide an abutment surface for the device.

FIGURE 2

At least one drawing originally filed was informal and the print reproduced here is taken from a later filed formal copy.

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FIGURE 7

A NOISE-REDUCING DEVICE FOR A VEHICLE

TECHNICAL FIELD

The present disclosure relates to a noise-reducing device for a vehicle. Particularly, but not exclusively, the invention relates to a device for reducing tyre cavity noise. Aspects of the invention relate to a device, to a wheel and to a vehicle.

BACKGROUND

It has been an aim in the automotive industry to produce lightweight vehicles, with a view to improving the fuel efficiency of such vehicles, reduce emissions and reduce costs. However, this reduction in weight has contributed to an increase in powertrain and road noise levels inside the vehicle. Accordingly, an important marketing and design concern for modern vehicles is to reduce the level of noise and vibration that is experienced by the occupants.

There are many sources of noise in a vehicle, but as engines become more refined and produce less noise, the contribution of road I tyre interactions becomes more noticeable. In modern vehicles, as the vehicle speed exceeds 40km/h, these road / tyre interactions become the dominant source of interior noise and vibration.

There are two significant contributors to the interior noise related to road/tyre interactions: external noise generated by vibration of the tyre on the road surface; and tyre cavity noise (TCN). TCN originates from resonance of the air column inside the tyre cavity as the tyre wall vibrates due to contact with the road surface. TCN is tonal in nature; that is to say it has one prominent frequency. Depending on the tyre size, TCN often occurs at frequencies between 180 and 250 Hz.

It is known for tyres to contain foam to reduce TCN. However, this is an expensive solution, particularly as the noise-reducing foam must necessarily be replaced when the tyre is changed.

Known noise-reducing devices either require the shape of the wheel to be modified fairly extensively such that it complements the shape of the noise-reducing device, allowing the device to be attached to the wheel or require the noise-reducing device to have components for positioning the device on the wheel. Such modifications are both costly and time1 consuming. Furthermore, this arrangement precludes retrofitting of noise-reducing devices to existing wheels, thereby limiting implementation of the devices.

It is against this background that the present invention has been devised.

SUMMARY OF THE INVENTION

Aspects and embodiments of the invention provide a noise-reducing device, a wheel and a vehicle as claimed in the appended claims.

According to an aspect of the invention, there is provided a noise-reducing device for a vehicle wheel, the device comprising: at least one element arranged to be secured around a region of the wheel that is configured to form part of a tyre cavity; at least one cavity formed in the at least one element, the or each cavity having an opening to provide communication between the or each cavity and the tyre cavity; and a fastening member arranged to secure the or each element around the region of the wheel; wherein the or each cavity is arranged to define at least in part a chamber that acts as a Helmholtz resonator when the device is installed onto the wheel; and the at least one cavity has a width substantially corresponding to the width of the or each element.

This aspect of the invention provides the advantage that the noise-reducing device is self-retaining on a wheel. In addition, the device of the present invention is advantageously light in weight and is sized so as to avoid intruding on the other components. Since the at least one cavity has a width substantially corresponding to the width of the or each element, the device is advantageously lighter than known devices. In particular, the width of the or each element of the device may be sized primarily in dependence on the size of the cavity which they define without the need for the or each element to comprise additional features extending laterally therefrom for locating the device with respect to a rim of the wheel.

The or each cavity may be defined by a concavity in the or each element, and wherein a perimeter of the or each concavity is arranged to seal against a surface of the wheel when the device is fitted to the wheel so that the surface of the wheel and the or each concavity together define the or each chamber, in use. Alternatively, the or each cavity may be closedbacked to define a self-contained chamber.

The device may comprise a fastening member arranged to encircle the or each element and to apply inward radial force to press the elements onto the wheel, in use. In some embodiments, the device comprises at least two elements. The or each element may comprise a circumferential groove arranged to receive the fastening member. The device may comprise a further fastening member. The device may comprise a further circumferential groove adapted receive the further fastening member.

In an embodiment, the or each opening may be formed on a respective protrusion that extends into the or each cavity, and wherein the or each protrusion is provided with a passage which communicates with the respective opening. The or each opening may be flush with an outer surface of the device. Each element may comprise the same number of cavities. Each element may be substantially identical.

The invention also provides a wheel comprising a noise-reducing device as described above. The wheel may comprise an upstand arranged to provide an abutment surface for the noise-reducing device. The wheel may also comprise a damping layer and/or an adhesive layer between the device and the wheel. In another aspect, the invention also provides a wheel comprising a wheel comprising an upstand arranged to provide an abutment surface for a noise-reducing device.

The invention also provides a vehicle comprising the noise-reducing device or the wheel described above.

In a further aspect, the invention provides a method of reducing tyre cavity noise, the method comprising: locating the or each element of a noise-reducing device as described above around a region of the wheel that is configured to form part of a tyre cavity, comprising positioning the or each element in abutment with an upstand of the wheel; securing the or each element around the region of a wheel such that the or each element forms a loop when secured to the wheel; and using the or each element to define at least in part a chamber that acts as a Helmholtz resonator when the device is installed. The method may also comprise the step of sealing a perimeter of a cavity formed in one of the elements against a surface of the wheel to define the chamber.

Within the scope of this application it is expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, in the claims and/or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination. That is, all embodiments and/or features of any embodiment can be combined in any way and/or combination, unless such features are incompatible. The applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to amend any originally filed claim to depend from and/or incorporate any feature of any other claim although not originally claimed in that manner.

BRIEF DESCRIPTION OF THE DRAWINGS

One or more embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

Figure 1 is a perspective view of a vehicle incorporating a noise-reducing device;

Figure 2 is a perspective view of a noise-reducing device in accordance with an embodiment of the present invention, including magnified views of two portions of the noise-reducing device;

Figure 3 is a view of the noise-reducing device of Figure 2 installed on a wheel of a vehicle;

Figure 4 is a perspective view of the noise-reducing device of Figure 2 installed on a wheel of a vehicle;

Figure 5 is a magnified view from the side of a portion of the noise-reducing device of Figure 2 installed on a wheel of a vehicle;

Figure 6 is a cross-section view of the noise-reducing device of Figure 2 installed on a wheel of a vehicle; and

Figure 7 is a perspective view of a section of the noise-reducing device of Figure 2, showing an embodiment of an attachment mechanism of the device.

DETAILED DESCRIPTION

Referring to Figure 2, a noise-reducing device 10 in accordance with an embodiment of the present invention is shown. The noise-reducing device 10 is generally annular in form and attaches around a vehicle wheel (not shown). The noise-reducing device 10 is open-backed and cooperates with the wheel to create chambers that act as Helmholtz resonators to damp vibration of an air column defined within a tyre cavity, the tyre cavity being defined as the volume enclosed by the surface of the wheel rim and the interior surface of a fitted tyre.

Certain noise-reducing devices that fit to the vehicle wheel are known and such devices typically rely on Helmholtz resonators as vibration dampers. It is also known to use Helmholtz resonators to reduce noise in exhaust and air intake systems.

In its simplest form, a Helmholtz resonator includes a hollow main body defining an internal chamber, the chamber having a single outlet that is formed in a protruding neck extending from the main body. A well-known example of Helmholtz resonance is the sound generated when air is blown across the top of an empty bottle. A Helmholtz resonator has a natural resonant frequency, known as the Helmholtz frequency, which is dependent on a number of parameters, for example the length of the neck or the volume of the cavity.

The invention relates to a noise-reducing device which acts as a Helmholtz resonator device when fitted to awheel.

Referring to Figure 1, there is shown a vehicle 90 provided with front and rear wheels having tyres, each wheel being provided with a noise-reducing device of an embodiment of the invention.

The noise-reducing device 10 may be formed of a single element 12 or from multiple elements, for example from two halves. In the embodiment shown in Figure 2, the noise-reducing device 10 is formed from a single element 12 that is sized to fit around a wheel in use. As will be explained later, the element 12 may be fastened to the wheel in different ways.

The width of the device 10 is relatively small compared with its radius, and is less than the width of the wheel. An inner surface 20 of the noise-reducing device 10 is provided with concavities 18. In the embodiment shown in Figure 2, each concavity 18 occupies almost a quarter of the overall circumference of the device 10. These concavities 18 are separated by sealing members 22 that define the perimeters of the concavities 18.

The concavities 18 may take many different shapes and their cross-sections may vary around the circumference of the device 10 so as to tailor the vibration response of the device 10 as required.

Each concavity 18 includes a single opening 70 that provides communication between the concavity 18 and the outer surface 16 of the device 10. The opening 70 of the device 10 is flush with the outer surface 16, while on the inner surface 20 a protrusion into the concavity 18 defines a neck 28 on which the opening is located.

As noted above, the wall of the noise-reducing device 10 has an opening 70 to allow air to pass between the tyre cavity and the chamber via the neck 28. The neck 28 is defined by a box-like protrusion that extends axially into a chamber along the inner surface 20 of the noise-reducing device 10.

The opening 70 to the neck 28 on the outer surface 16 of the noise-reducing device 10 is flush with that surface 16. This provides a degree of protection from ingress of fluids such as puncture sealant or water, which could otherwise alter the sonic characteristics of the resonator.

The length and cross-sectional area of the opening 70 and/or neck 28 are relevant parameters for determining the Helmholtz frequency. Therefore, the resonator can be tuned to a desired frequency, typically the TCN frequency, by varying the relevant lengths or crosssectional areas. In other embodiments, the form of the neck 28 may be adapted to improve the sound absorption capacity of the resonator. For example, opposing walls of the opening 70 may be parallel or the walls may be angled to form a tapered neck.

As noted above, the wall of the noise-reducing device 10 has an opening 70 to allow air to pass between the tyre cavity and the chamber via the neck 28. The neck 28 is defined by a box-like protrusion that extends axially into the chamber along the inner surface 20 of the noise-reducing device 10. The edges of the protrusion are rounded for ease of manufacturing. A central bore (not shown) is formed in the neck 28 and provides communication between the chamber and the tyre cavity.

The opening 70 to the neck 28 on the outer surface 16 is flush with that surface 16. This provides a degree of protection from ingress of fluids such as puncture sealant or water, which could otherwise alter the sonic characteristics of the resonator.

The length and cross-sectional area of the bore (not shown) of the neck 28 are both relevant parameters for determining the Helmholtz frequency. Therefore, the resonator can be tuned to a desired frequency, typically the TCN frequency, by varying the length or cross-sectional area of the bore (not shown). In other embodiments, the form of the neck 28 may be adapted to improve the sound absorption capacity of the resonator. For example, in this embodiment opposing walls of the bore (not shown) are parallel, but in other embodiments the walls may be angled to form a tapered neck.

Noise-reducing devices 10 in accordance with embodiments of the present invention allow reduction of the TCN close to its source, preventing transfer of noise to the vehicle cabin (not shown). As noted above, the air column inside the tyre cavity vibrates due to the vibration of the tyre wall caused by contact with the road surface. This establishes a standing wave inside the tyre cavity with the characteristic frequency of the TCN. Since the Helmholtz resonators of the noise-reducing device 10 are tuned to the same frequency as the TCN, they exhibit Helmholtz resonance in response to this excitation. Each Helmholtz resonator acts to damp the vibration of the air column by acting as a simple harmonic oscillator. By analogy with a mass on a spring, the air within the chamber behaves like the spring and the air within the neck 28 behaves like the mass. The oscillations of the air column are therefore damped and the TCN is reduced.

To maximise the effectiveness of the noise-reducing device 10 at a particular frequency, in this embodiment all of the resonators are identical. Alternatively, dissimilar resonators may be tuned to the same frequency if desired through control of the relevant parameters. In other embodiments, the resonators may be tuned to different frequencies, allowing the device to reduce noise across a range of frequencies in order to handle variations in the TCN frequency caused by changes in temperature, for example. This may be achieved by varying any one or more of the relevant parameters of the resonators; such as the resonator chamber volume or length of the resonator neck 28.

Around the edge of a concavity 18 a channel (not shown) is formed on the inner surface 20 of the noise-reducing device 10. A sealing member 22 is received in the channel and is used to ensure an airtight seal between the noise-reducing device 10 and the wheel (not shown). This seal maintains the resonance characteristics of each of the chambers so that each Helmholtz resonator remains tuned to the TCN frequency. Ensuring firm contact between the noise-reducing device 10 and the wheel also prevents rattle of the device 10.

The sealing material may be a rubber O-ring or may be provided in the form of a layer of foam or adhesive covering the surface area in contact with the wheel. The sealing material may form the sealing member 22 after being injection moulded into the device 10, for example using twin-shot injection, or using overmoulding. In closed-backed embodiments, no seal is required as the chambers are self-contained. However, foam or adhesive material may still be used between the device 10 and the wheel to minimise transmission of vibration.

Referring to Figure 3, the device 10 of Figure 2 is shown encircling a wheel of a vehicle. As will be familiar to the skilled reader, the wheel includes a roughly cylindrical central portion 42 with radially enlarged lips 44a, 44b at either side, those lips 44a, 44b being arranged to hold a tyre (not shown).

As shown in Figure 3, the wheel includes a region of the wheel 40 that that is configured to form part of a tyre cavity. The region of the wheel 40 is located between the radially enlarged lips 44a, 44b.

The profile of the central portion 42 of the wheel 40 is slightly tapered and as such, the circumference of the wheel 40 on the outboard side 46 is smaller than the circumference on the inboard side 48. The wheel 40 also includes a tyre pressure monitoring system (TPMS) 50, which protrudes from the curved surface 52 of the wheel 40 at a point close to the outboard lip 44a.

The interior circumference and profile of the noise-reducing device 10 are arranged to correspond to the circumference and taper of the central portion 42 of the wheel 40. Therefore, when the device 10 is installed around the wheel 40, the inner surface 20 of the device 10 seals against the surface 52 of the central portion 42 of the wheel 40, thus enclosing a volume of air within each concavity 18. This creates four separate resonance chambers when the device 10 is retained against the wheel 40.

As the device 10 forms a continuous ring, it cannot fall off the wheel 40 once assembled. Moreover, as the device 10 is sized for a close fit with the wheel 40, it will generally maintain its position on the wheel 40 once installed. In this way, the device 10 is self-retaining on the wheel 40.

It is noted that, as the noise-reducing device 10 is open-backed, the concavities 18 are not closed to form resonance chambers until the device is attached to the wheel 40. The noisereducing device 10 therefore cooperates with the wheel 40 to create the partially closed volumes that are required for Helmholtz resonance. In this way, the noise-reducing device 10 of this embodiment of the invention can be more lightweight and less costly to manufacture than the closed cell resonator arrangements known from the prior art.

In alternative embodiments the device may be closed-backed, in which case the resonance chambers are formed integrally as part of the device rather than in conjunction with the wheel 40. In comparison with the open-backed arrangement described above, a closedbacked arrangement provides benefits such as increased strength and robustness, along with easier installation by virtue of the fact that there is no need to ensure a seal around the concavities as with the open-backed design. Furthermore, as with the open-backed arrangements, a closed-back embodiment also has the advantage that the noise-reducing device 10 is self-retaining on the wheel 40, in that the wheel 40 does not require modification in order to support the device.

Open-backed arrangements can be manufactured using injection moulding or extrusion moulding, for example, whereas blow moulding may be required for a closed-backed arrangement.

Referring to Figure 4, the noise-reducing device 10 of Figure 4 is shown attached to a wheel 40 of a vehicle. It will be appreciated by a person skilled in the art that connection of the noise-reducing device 10 to the wheel 40 can be realised in many different ways. For example, a fastening member 54 may fit into at least one groove 24 on the exterior surface 16 of the device 10 to ensure that the device 10 is held firmly against the surface 52 of the wheel 40. The fastening member 54 is arranged to encircle the device 10 and to apply inward radial force to press the device 10 onto the wheel 40.

In the embodiment shown in Figure 4, there are two grooves 24 on the exterior of the noise-reducing device 10, each of which is adapted to receive a fastening member 54 to ensure that the device 10 is held firmly against the surface 52 of the wheel 40. Furthermore, the presence of two grooves 24 on the device 10 results in the device 10 having a raised central circumferential section 14 along its entire length. The fastening member 54 is arranged to encircle the device 10 and to apply inward radial force to press the device 10 onto the wheel 40. The ends of the fastening member 54 may have a buckle or cable tie strap mechanism, or they may be fused or bonded together.

The fastening member 54 may be comprised of any suitable material. In one embodiment, the fastening member 54 is made of stainless steel. In another embodiment, the fastening member 54 is a jubilee clip.

In one embodiment, the fastening member 54 is fastened to the noise-reducing device 10 using spot welding. The gap between the ends of the device 10 (best seen in Figure 3) allows space for such spot welding. Spot welding is generally used where the straps are formed of steel.

Figure 5 shows a magnified view of a portion of the noise-reducing device 10 installed on a wheel 40 of a vehicle. It can be seen that the noise-reducing device 10 is adjacent to the TPMS 50, which protrudes from the curved surface 52 of the wheel 40 at a point close to the outboard lip 44a.

Figure 6 shows the assembly of Figure 4, namely the noise-reducing device 10 installed on the wheel 40, in axial cross-section. As can be seen, the device 10 is held against the central portion 42 of the wheel 40, with an outer edge or abutment surface 30 of the noisereducing device 10 abutting an upstand 45.

In various previous noise-reducing devices, a flange or spacer is used to position the device on a wheel. However, this can be disadvantageous, for example at high speeds where an imbalance may be created.

Advantageously, the upstand 45 may be used to position the noise-reducing device 10 on the wheel 40. In particular, this provides benefits to an automated process of positioning the noise-reducing device 10 on the wheel 40, as the upstand 45 allows fast and effective positioning of the noise-reducing device 10 without the need for further components on the noise-reducing device 10, allowing its size and weight to be reduced.

Additionally, since the upstand 45 allows the size of the noise-reducing device 10 to be reduced, the noise-reducing device 10 can be adjacent to the TPMS 50 rather than overlapping and/or encircling it.

In some embodiments of the invention, the noise-reducing device 10 is formed from two elements or halves that connect at diametrically opposed points on the device 10. It will be appreciated that although such elements of the device are referred to as ‘halves’ of the device, the two parts need not be identical nor form exact halves in shape, size nor mass of the whole device. The connection between the two sections may be realised in many different ways. Each half may be a band of plastics material formed as a half-ring, such that the two halves together create a continuous ring. The width of the device 10 is relatively small compared with its radius, and is less than the width of the wheel.

In the embodiment shown in Figure 7, the noise-reducing device 10 is formed from two elements that connect at diametrically opposed points on the device 10. The outer surface 16 of each element 12 of the noise-reducing device 10 includes a depression 80 extending from its connecting edge 82. When the connecting edges 82 of the two halves 12 of the device 10 are abutted against one another the depressions 80 align, forming a single continuous recess 81 spanning the joint 84 on the outer surface 16 of the device 10. This recess 81 has a generally hourglass shape and an attachment piece 86 or clip 86 of complementary shape is provided to fit inside the recess 81. By virtue of the clip’s 86 hourglass shape, the two elements 12 of the device 10 cannot be pulled apart when the clip 86 is inserted. The fastening member 54 fits over the clip 86 to hold it in place in the recess 81.

Additionally or alternatively, one element 12 of the device 10 may be provided with pins (not shown) extending from the connecting edge 82 and the other element 12 with holes (not shown) to receive said pins, to enhance the integrity of the joint 84.

Providing the noise-reducing device 10 in two ‘halves’ 12 allows easy installation to a wheel 40 and the abutment surface 30 facilitates reliable locating of the device 10 on the wheel 40.

It will be appreciated by a person skilled in the art that the embodiments of the present invention described above could be modified to take many other alternative forms without departing from the inventive concept defined by the claims. For example, an adhesive band or foam could be provided underneath the device to decouple it from the wheel vibrations.

Claims

1. A noise-reducing device for a vehicle wheel, the device comprising:

at least one element arranged to be secured around a region of the wheel that is configured to form part of a tyre cavity;

at least one cavity formed in the at least one element, the or each cavity having an opening to provide communication between the or each cavity and the tyre cavity; and a fastening member arranged to secure the at least one element around a region of the wheel;

wherein the or each cavity is arranged to define at least in part a chamber that acts as a Helmholtz resonator when the device is installed onto the wheel; and the at least one cavity has a width substantially corresponding to the width of the or each element.

2. The device of claim 1, wherein the device comprises at least two elements.

3. The device of claim 1 or claim 2, wherein the or each cavity is defined by a concavity in the at least one element, and wherein a perimeter of the or each concavity is arranged to seal against a surface of the wheel when the device is fitted to the wheel so that the surface of the wheel and the or each concavity together define the or each chamber, in use.

4. The device of claim 1 or claim 2, wherein the or each cavity is closed-backed to define a self-contained chamber.

5. The device of any of claims 1 to 3, wherein the fastening member is arranged to encircle the or each element and to apply inward radial force to press the or each element onto the wheel, in use.

6. The device of claim 5, wherein the or each element comprises a circumferential groove arranged to receive the fastening member.

7. The device of claim 5 or claim 6, wherein the device comprises a further fastening member arranged to encircle the or each element and to apply inward radial force to press the or each element onto the wheel, in use.

8. The device of claim 7, wherein the device comprises a further circumferential groove arranged to receive the further fastening member.

9. The device of any preceding claim, wherein the or each opening is formed on a respective protrusion that extends into the or each cavity, and wherein the or each protrusion is provided with a passage which communicates with the respective opening.

10. The device of any preceding claim, wherein the or each opening is flush with an outer surface of the device.

11. The device of any preceding claim, wherein each element comprises the same number of cavities.

12. The device of claim 11, wherein each element is substantially identical.

13. A wheel comprising a noise-reducing device according to any preceding claim.

14. The wheel of claim 13, wherein the wheel comprises an upstand arranged to provide an abutment surface for the noise-reducing device.

15. The wheel of claim 13 or claim 14, comprising a damping layer and/or an adhesive layer between the device and the wheel.

16. A vehicle comprising the noise-reducing device of any of claims 1 to 12, or the wheel of any one of claims 13 to 15.

17. A noise-reducing device, a wheel or a vehicle substantially as described herein, with reference to the accompanying figures.

18. A method of reducing tyre cavity noise, the method comprising:

locating the or each element of a device according to any of claims 1 to 12 around a region of the wheel that is configured to form part of a tyre cavity, comprising positioning the or each element in abutment with an upstand of the wheel;

securing the or each element around the region of a wheel such that the or each element form a loop when secured to the wheel; and using the or each element to define at least in part a chamber that acts as a Helmholtz resonator when the device is installed.

19. The method of claim 18, comprising sealing a perimeter of a cavity formed in one of the elements against a surface of the wheel to define the chamber.

Intellectual

Property

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Application No: Claims searched:

GB1615111.0

1-19