Pneumatic tire

Abstract

To provide an advanced noise attenuating pneumatic tire.SOLUTION: A pneumatic tire 1 comprises: two spaced apart beads 3; a tread portion 10; a pair of sidewalls 2 extending radially inward from axially outer edges of the tread portion defining tread width to join the respective beads; a carcass 9; an inner liner 13 covering the carcass and defining a tire cavity when mounted on a rim; and a plurality of layers made of open-cell noise attenuating foam strip material 30 mounted by stacking on the inner liner and arranged in a radially lower region of the tread portion of the tire cavity, where each layer has axial width from 20% to 80% of the tread width and radial thickness from 5% to 20% of the tread width, and the plurality of layers as a whole fills from 8% to 40% of volume of the tire cavity.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention is directed to pneumatic tires containing a noise-damping foam strip material. Further, the present invention is directed to a method of manufacturing a tire.

Background Art

[0002] Tires generate noise during driving. In the art, it is known to attenuate at least a portion of the noise by including a foamed material within the tire cavity, thereby attenuating the noise in the tire cavity. An example of such a noise-damping material is described in U.S. Patent Application Publication No. 20120125507A1, where a single layer of rubber foam is applied to the inner liner of the tire. However, a relatively thick layer results in internal strain in the foamed material due to bending and flexing, which can cause fatigue cracks and thus provides limited durability. In other examples, as in U.S. Patent Publication No. 20110030865A1, the tire is almost completely filled with foam. Filling essentially the entire tire cavity with foam is expensive and can also have an adverse effect on the driving performance of the tire as well as its cooling characteristics. Attenuating noise has become even more important recently in view of the increasing number of electric vehicles, which generate very low engine noise and, correspondingly, do not significantly mask tire noise. Since tire noise is more prominent in the operation of electric vehicles, such vehicles should be optimally equipped with tires that generate very little noise so that the tire noise is not apparent. In today's world, the long-felt need for tires continues, which is to generate lower noise levels during operation, and the demand for advanced noise cancellation technology for pneumatic tires is higher than ever. However, there remains significant room for improvement in this tire technology field.

Summary of the Invention

Problems to be Solved by the Invention

[0003] A first object of the present invention is to provide an advanced noise-reducing pneumatic tire. Another object of the present invention is to provide a relatively easy-to-produce advanced noise-reducing pneumatic tire that can be produced at a commercially viable cost. Yet another object of the present invention is to provide an advanced noise-reducing tire having a flexible noise-reducing system that can be adapted to different tires, particularly different tire sizes. Yet another object of the present invention is to provide a pneumatic tire provided with a foam noise attenuator, enabling a more homogeneous weight distribution and / or having less tension within the damping material. The scope of the present invention is defined by the independent claims. Preferred embodiments are recited in the dependent claims as well as in the following description.

Means for Solving the Problems

[0004] Accordingly, in a first aspect of the present invention, there is provided a pneumatic tire, the pneumatic tire including two spaced bead portions, a tread portion, a pair of sidewalls extending radially inward from the axial outer edges of the tread portion defining a tread width and coupling to respective ones of the beads, a carcass, and an inner liner covering the carcass and defining a tire cavity. Further, the tire includes a plurality of layers formed of a continuous foam noise-reducing foam strip (material) laminated and attached to the inner liner and disposed in a region radially below the tread portion of the tire cavity, each layer having an axial width ranging from 20% (preferably 30%) to 80% of the tread width and a radial thickness ranging from 5% to 20% of the tread width, and the plurality of layers as a whole filling from 8% (preferably 15%) to 40% of the volume of the tire cavity.

[0005] Providing a plurality of layers of the foam strip material stacked, or in other words, provided in a stacked manner or arrangement, on the one hand allows the use of the same or similar strip materials depending on the desired level of noise attenuation, and on the other hand allows the use of the same or similar materials for different tire sizes. Furthermore, the inventors have found that the desired amount of the foam material in the tire cavity constitutes a good compromise between material cost, the covered space and / or damping properties. The open-cell damping material is much more suitable for attenuating noise and / or vibration than the closed-cell foam material. In particular, the acoustic attenuation of the tire cavity resonance is supported by the noise attenuation characteristics of the present invention. However, the open-cell noise attenuation foam material should not be understood herein as simply constituting a three-dimensional net and covering a completely reticulated foam substantially free of bubbles or bubble walls. Such materials can have relatively good ventilation properties but are not suitable for attenuating noise. Furthermore, the latter materials are relatively expensive. Another advantage of the present invention lies in the possibility of having a plurality of relatively thin layers arranged in a stacked manner instead of one thick layer. This helps to fix one or more ends of the plurality of layers in an easier way, and the strain and / or bending force is limited due to the flexibility of each layer. The curvature of the tire is more easily followed by the plurality of layers, and each of the plurality of layers has a different length (depending on the surface to which it is attached). This also results in an easier installation procedure and reduces the risk of the foam strip loosening from the inner liner. The risk of rupture of the strip material due to the forces during installation and / or use during the life of the tire is reduced.

[0006] In one embodiment, the open-cell noise attenuation material has a density of from 0.01 g / cm 3 to 1 g / cm 3 , and optionally from 0.02 g / cm 3 to 0.5 g / cm 3 . Such materials have been found to be particularly interesting. In other embodiments, the open-cell noise-damping foam strip material contains 55% to 95% (or preferably 60% to 90%) of open cells (of all the cells) in the material. Open cells can be understood as cells having at least one opening. In other words, open cells are not completely closed or not completely surrounded by cell walls. Closed-cell foams are not included in the above range because most of the cells of this foam type are independent. Completely or almost completely reticulated foams have few walls and rather form a continuous lattice, so neither falls within that range. Whether a cell is open (i.e., closed) can be determined, for example, by optical microscopy, SEM, or NMR. The cell size typically ranges from 10 μm to 1 mm (maximum diameter).

[0007] In other embodiments, the density of the first layer of open-cell noise-damping foam strip material in contact with the inner liner is lower than the density of the second layer of open-cell noise-damping foam strip material attached to the first layer. A higher density can improve acoustic attenuation, but allows for lower heat conduction and can have a negative impact on the durability of the foam and / or the tire. An open-cell noise-damping foam strip material with a lower density can improve heat conduction but has more limited acoustic attenuation properties. In still other embodiments, the foam material can be composed of one or more of the following: polyurethane foam, polyethylene foam, foamed rubber, etc. Suitable polyurethane foams are typically produced by the polymerization of diisocyanates and polyols in the presence of a suitable foaming agent. In the practice of this invention, a wide variety of rubber foams can be utilized, and natural rubber, synthetic polyisoprene rubber, polybutadiene rubber, nitrile rubber, and styrene-butadiene rubber foams are commonly used. Such foamed rubbers are typically produced by foaming natural or synthetic rubber latex with a chemical foaming agent. Chemical foaming agents are typically azo compounds such as azodicarbonamide, hydrazine compounds, carbohydrazide, tetrazole, nitroso compounds, and / or carbonates such as sodium bicarbonate. In other embodiments, the open-cell noise attenuation foam strip material is adapted and / or used for attenuating tire cavity noise, particularly in the range of 100 Hz to 300 Hz, or in the range of 100 Hz to 200 Hz, or in the range of 200 Hz to 300 Hz. In other embodiments, the open-cell noise attenuation foam strip material does not include (essentially) a reticulated foam.

[0008] In still other embodiments, the plurality of layers are formed by strips that are laminated and wound in a spiral. The advantage of such an embodiment is its adaptability for application in mass production. In still other embodiments, the first layer of the plurality of layers has a first butt joint disposed at a first circumferential position of the tire cavity, and the second layer of the plurality of layers has a second butt joint disposed at a second circumferential position of the tire cavity, and the second circumferential position is different from the first circumferential position. In other words, each layer can be made of a single piece of foam strip material, and the single piece of foam strip material is provided circumferentially within the tire cavity and is closed at its two ends by butt joints. If a tire having only a single layer of foam strip material (not according to the present invention) has only one butt joint, the result is an imbalance in the position of the joint. Having a plurality of laminated layers and having butt joints in different circumferential directions (or angles) helps to reduce such an imbalance.

[0009] In other embodiments, the position of the second butt joint of the second layer is offset (or rotated) circumferentially by 100° to 260° from the angular position of the first butt joint of the first layer, and optionally, is arranged at an angular position between 130° and 230°. This reveals that an essentially opposite arrangement may be particularly interesting, for example, to avoid imbalance. Further, the joints arranged at the bottom of the stack of multiple layers are protected by the upper multiple layers since the joints are not provided at the same angular positions. Thereby, the probability of loosening of the entire foam strip is further reduced as compared to providing one relatively thick strip.

[0010] In yet other embodiments, the plurality of layers have one or more of an axial width of 50% to 70% of the tread width, a radial thickness of 5% to 15% of the tread width, and optionally, as a whole, filling 20% to 40% of the volume of the tire cavity. This combination of parameters has been found by the inventors to be more desirable. This does not necessarily mean that all layers have the same width and / or thickness (for a wider range). As referred to herein, the term tire cavity is understood as the volume (in particular not mounted and in a non-inflated state) surrounded by the inner liner of the tire and is understood as the volume closed by a (virtual) circumferential ring-shaped plane that contacts the radially innermost edges of both bead portions.

[0011] In other embodiments, the plurality of layers are arranged essentially parallel to the equatorial plane of the tire and each has a length covering at least 80%, preferably at least 90% or 99% of the inner circumference of the tire. In particular, the plurality of layers may be arranged continuously, laminated, or wound spirally. In yet other embodiments, the number of the plurality of layers is two to four layers, preferably two or three layers. This number can provide a good balance between the flexibility required for installing the layers and the amount of work. In yet other embodiments, the first layer attached to the inner liner is longer than the second layer attached to the first layer. In particular, the length of the radially innermost circumferential surface of the second layer is smaller than the length of the radially innermost circumferential surface of the first layer. Since both layers have different lengths, the pressure on the strip material is smaller than in the case of having a single relatively thick layer in the radial direction. In yet other embodiments, the first foam strip layer attached to the inner liner has an axial width that is smaller than the second layer that is laminated (or, in other words, radially inward) to the foam strip layer attached to the inner liner. Such embodiments can help improve the cooling of the tire's tread and / or crown regions as less insulating material is directly attached to the inner liner. Preferably, the second layer has a width that is at least 20% larger than the first layer attached to the inner liner and, optionally, at most 50% larger than the first layer. Such an arrangement is not possible with an off-the-shelf foam strip material when using only a single layer.

[0012] In yet other embodiments, at least two of the plurality of layers are mechanically connected (or shaped to fit), in other words, the plurality of layers are connected to each other along the length of the plurality of layers. This allows for the avoidance of adhesive materials and adhesives, thereby reducing the environmentally friendly ground contact surface and simplifying production. Preferably, the connection is essentially continuous over the length of the strip. In yet other embodiments, the layers are mechanically connected by one or more. It is a double-tail connection, a hook-and-loop (registered trademark) connection, or other surface fastener connection, a plastic pin having lateral protrusions at both ends that extends through the plurality of layers and holds the plurality of layers as a whole. A double-tail connector may generally cover a T-shaped connector.

[0013] In yet other embodiments, at least one of the plurality of layers has a butt joint that is mechanically connected on its joining side. This can also help avoid adhesion. For example, the above-described means for connection can be used. In yet other embodiments, the tire does not include a sealing material, and in particular, the inner liner does not include a sealing material. In yet other embodiments, the plurality of layers are interconnected with each other by at least one. For example, an adhesive, a hook-and-loop fastener connection tape such as Velcro tape, an adhesive tape, a double-sided adhesive tape, a plastic connector, a plastic screw. In yet other embodiments, the radially outermost foam strip material layer is attached to the inner liner by at least one of a sealing material and an adhesive. When the tire has a seal on the inner liner within the tire cavity, this sealing material can be used as an adhesive.

[0014] In yet other embodiments, at least one of the plurality of layers is coated with a metal. The metal coating helps to keep heat away from hot spots. This is particularly interesting for the surface of the layer facing the inner liner of the tire and / or attached to the inner liner. The metal coating can be done by various methods such as metallization, galvanic coating, sputtering, chemical vapor deposition and / or foil coating. In yet other embodiments, at least two of the layers have one or more of the same radial thickness and the same radial width, and the plurality of layers are made of the same material as needed. Such parameters help to reduce costs and / or facilitate attachment. In an embodiment, the tire is one of a truck tire, a bus tire, and a passenger car tire. In particular, a vehicle having a closed passenger compartment can obtain the benefits of the present invention because it can reduce the noise level in the passenger's passenger compartment. For example, the tire is a bus tire with a rim size of 22.5 inches.

[0015] In a second aspect of the present invention, a tire rim assembly (or wheel) is provided, the assembly including a rim and a tire attached to the rim, the tire including two spaced beads, a tread portion, and a pair of sidewalls extending radially inwardly from the axial outer edge of the tread portion and joining to the respective beads, the axial outer edge of the tread portion defining a tread width, a carcass, and an inner liner covering the carcass and surrounding the tire cavity as a whole with the rim. Further, the tire includes a plurality of layers, the plurality of layers being a continuous foam noise attenuation foam strip material laminated and attached to the inner liner, inside the tire cavity in a radially inner region of a lower portion of the tread portion, a single layer having an axial width of 30% to 80% of the tread width and a radial thickness of 5% to 20% of the tread width, and the plurality of layers filling 15% to 45% of the volume of the tire cavity as a whole.

[0016] In a third aspect of the present invention, a method of manufacturing a foam-damped pneumatic tire is provided, the method including the steps of providing a pneumatic tire having a tire cavity, attaching a first layer of a continuous foam noise attenuation foam strip material circumferentially to the inner liner of the tire, and attaching a second layer of a continuous foam noise attenuation foam strip material to the first layer. In one embodiment, the method further includes the step of attaching a third layer on the second layer. In other embodiments, the method further includes the steps of providing a first strip of the continuous foam noise attenuation foam strip material, attaching the first strip circumferentially to the inner liner of the tire, and, optionally, closing the first strip at its two ends by butt joints. In other embodiments, the method further comprises providing a second strip of the closed-cell noise attenuating foam strip material, circumferentially attaching the second strip to the first strip, and optionally closing the second strip at its two ends by butt joints, where optionally the second strip is shorter than the first strip.

[0017] In other embodiments, the butt joint of the second layer is disposed at an angular position offset (or rotated) circumferentially from the angular position of the first butt joint of the first layer, in the range of 100° to 260°, and optionally in the range of 130° to 230°. In other embodiments, a strip of closed-cell noise attenuating foam strip material is provided, the strip is longer than the inner circumference of the tire, the strip is applied spirally parallel to the equatorial plane of the tire, and the strip is applied in a stacked manner to form at least two (or at least three) layers of the closed-cell noise attenuating foam strip material in the radial direction. The terms damping and dampening are considered interchangeable within the scope of the present disclosure. It is emphasized that one or more aspects, embodiments, or features thereof can be combined with each other within the scope of the present invention. The structure, operation, and advantages of the present invention will become more apparent upon consideration of the following description in conjunction with the accompanying drawings.

Brief Description of the Drawings

[0018]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Mode for Carrying Out the Invention

[0019] FIG. 1 is a schematic cross-sectional view of a tire 1 for a bus or truck. The tire 1 includes a tread 10, an inner liner 13, a belt structure including a plurality of belt plies 12, a carcass ply 9, two sidewalls 2, and two bead regions 3 including a bead filler apex 5 and beads 4. The carcass ply 9 includes a pair of axially opposed ends 6, each of which is combined with each of the beads 4. Each axially end 6 of the carcass ply 9 may be folded around each bead 4 to a position fixing each axially end 6. The folded portion 6 of the carcass ply 9 can engage the axially outer surface of the two flippers 8 and the axially inner surface of the two chippers 7. As shown in FIG. 1, the illustrated tread 10 has four circumferential grooves 20, each groove essentially defining a U-shaped opening within the tread 10. According to a first embodiment of the present invention, the tire 1 includes two (laminated) layers 30 of noise damping foam strip material. They are attached radially inside the inner liner 13 and are preferably attached by a 5900 series including adhesives such as Henkel's Loctite® (registered trademark), for example 5900, 5910, and 5970. Both layers 30 are arranged circumferentially essentially parallel to the equatorial plane EP of the tire 1. The radial direction r, the circumferential direction c, and the axial direction a are shown for ease of reference. However, it should be noted that the shown directions of the axial direction a and the circumferential direction c do not limit the present invention. The volume covered by the two layers 20 is, according to the present invention, at least 8% (preferably 15%) of the tire cavity volume, but less than 40% of the latter. The volume of the tire cavity is understood as the volume surrounded by the inner liner of the tire (in particular, not mounted and in a non-inflated state) and is understood to be closed by a (virtual) circumferential ring-shaped surface that contacts the radially innermost edges of both bead portions 3. That surface is schematically shown in FIG. 1 by a dashed line connecting to the radially innermost edge of the tire 1.

[0020] As shown in FIG. 5, each layer of the multi-layer may be wound in the circumferential direction, and each layer 30 may have a butted joint 31. Preferably, the butted joints of different layers 30 are not provided at the same angle, and for example, as shown in FIG. 5, they are attached facing each other (shifted by 180 degrees in the circumferential direction). For clarity, such a tire 1 is not shown in FIG. 5. The axial direction a is shown at the center of the plurality of layers 30 arranged in the circumferential direction. Alternatively, as shown in FIG. 6, the plurality of layers 30' can also be laminated and wound in a spiral. This limits the number of joints and simplifies the attachment. As in other embodiments, the plurality of layers 30' may be, for example, adhered to each other. Alternatively, an adhesive tape or other means such as, for example, a Velcro connection may be used. Further options are described in the context of other embodiments.

[0021] The embodiment of FIG. 1 proposes a plurality of tire components including, for example, apex 5, chipper 7 and flipper 8, but such components are not essential for the present invention. Also, the folded end of the carcass ply 9 is not necessary for the present invention and may terminate axially inside the bead 4 rather than axially outside the bead 4 through the opposite side of the bead region 3. The tire can, for example, also have more or fewer than four grooves and can have a different number of belt plies than those shown.

[0022] Figure 2 shows another embodiment of a tire 101 having a plurality of layers 103, 103' of a continuous bubble noise attenuation foam strip material. For ease of reference, the same reference numerals as in FIG. 1 are used for other elements of the tire 101. The same is true for FIGS. 3 and 4. In contrast to the embodiment of FIG. 1, FIG. 2 shows a first layer 103 of a continuous bubble noise attenuation foam strip material having a first axial width and a second layer 103' of a continuous bubble noise attenuation foam strip material having a second axial width greater than that of the first layer 103. This arrangement may help improve the cooling of the tire in the region below the tread 10. This effect can be further improved by providing a continuous bubble noise attenuation foam strip material in which layer 103 has a lower density than layer 103'. Thus, layer 103' has better noise attenuation characteristics than layer 103, while allowing better cooling of the tread region than the arrangement shown in FIG. 1.

[0023] FIG. 3 shows yet another embodiment according to the present invention, wherein the tire 110 has four layers 130 of a continuous bubble noise attenuation foam strip material. The first layer 130 is attached to the inner liner 13 by a sealant layer 11. Thus, the sealant layer 11 acts as an adhesive. Sealants are typically used, for example, to seal punctures in the tread 10 by screws or nails. Such sealant materials are typically very adhesive and are known to those skilled in the art. Instead of adhering the plurality of layers 130 to each other, the plurality of layers 130 are connected to each other by a double-tail connection. In particular, each layer 130 has a male element on one side and a female element on the opposite side for mechanically interconnecting or fitting the plurality of layers to each other. Preferably, such interconnecting elements are provided in the central region of the plurality of layers 130. This modular system facilitates the addition of a plurality of layers depending on the actual tire. In this embodiment, adhesives are completely avoided.

[0024] Figure 4 shows another embodiment according to the invention, where the tire 111 has three layers 133 that are also mechanically interconnected by double-tail connectors. In this embodiment, the male double-tail connector element of the first layer 133 is adhered to the inner liner 13 of the tire. This configuration has the advantage that the male element has an axial width that is smaller than the overall axial width of the first layer 133, creating a distance between the male element and most of the surface of the layer 133 facing the inner liner 13 below the tread. This generates slots between the first layer 133 and the inner liner 13, improving the cooling characteristics in the example shown. The first layer 133 has female double-tail connector elements on the surface of the layer 133 opposite the surface where the male connector is located. In other words, the female connector is provided radially inside the layer 133, while the male connector is provided radially outside the layer 133. The same may be applied respectively to one or more layers attached to the first layer 133.

[0025] Modifications of the present invention are possible in light of the provided description. In any case, the above embodiments and examples should not be understood in a limiting sense. In particular, the features of the above embodiments may be replaced with each other or combined.

Claims

1. Two spaced bead portions (3), a tread portion, a pair of sidewalls (2) extending radially inwards from the axial outer edges of the tread portion defining the tread width and joining to respective said bead portions (3), a carcass (9), an inner liner (13) covering the carcass (9) and defining a tire cavity, a plurality of layers (30, 30’, 103, 103’, 130, 133) of a continuous cellular noise attenuation foam strip material laminated and attached to the inner liner (13) and disposed in a region of the tire cavity radially below the tread portion, an inflated tire comprising: each of said layers (30, 30’, 103, 103’, 130, 133) having an axial width of 20% to 80% of the tread width and a radial thickness of 5% to 20% of the tread width, and said plurality of layers (30, 30’, 103, 103’, 130, 133) as a whole filling 8% to 40% of the volume of the tire cavity, a first layer of said plurality of layers (30, 30’, 103, 103’, 130, 133) having a first butt joint (31) disposed at a first circumferential position of the tire cavity, a second layer of said plurality of layers having a second butt joint (31) disposed at a second circumferential position of the tire cavity, said second circumferential position being different from said first circumferential position, and the position of said second butt joint of said second layer being disposed at an angular position offset circumferentially between 100° and 260° from the angular position of said first butt joint of said first layer, an inflated tire.

2. The open cell noise dampening foam strip material has a density of 0.01 g / cm ３ to 1 g / cm ３ 2. The pneumatic tire of claim 1, having a density in the range of:

3. Said plurality of layers (30, 30’, 103, 103’, 130, 133) having an axial width in the range of 50% to 70% of the tread width, having a radial thickness in the range of 5% to 15% of the tread width, and / or filling 20% to 40% of the volume of the tire cavity as a whole, characterized by having one or more of the above, the inflated tire according to claim 1 or 2.

4. Each of said plurality of layers (30, 30', 103, 103', 130, 133) is arranged essentially parallel to the equatorial plane (EP) of said tire and / or has a length covering at least 80% of the inner circumference of said tire, a pneumatic tire according to any one of claims 1 to 3.

5. The first foam strip material layer (103) attached to said inner liner (13) has an axial width smaller than that of the second foam strip material layer (103') laminated on said first foam strip material layer (103) attached to said inner liner (13), a pneumatic tire according to any one of claims 1 to 4.

6. At least two of said plurality of layers (130) are mechanically connected to each other along their lengths, said connection being essentially continuous over the length of the foam strip material between the two laminated layers and / or said plurality of layers are mechanically connected by one or more of double-tail connections, one or more jigsaw connections, surface fasteners, plastic rivets, and plastic screws, a pneumatic tire according to any one of claims 1 to 5.

7. At least one of said plurality of layers has a butted joint (31) mechanically connected on its facing surface side, a pneumatic tire according to any one of claims 1 to 6.

8. Said plurality of layers (30, 30', 103, 103', 130, 133) are connected to each other by at least one of an adhesive, a surface fastener tape, an adhesive tape, a double-sided adhesive tape, a plastic rivet, and a plastic screw and / or the outermost foam strip material layer in the radial direction is attached to said inner liner (13) by at least one of a sealant material and an adhesive, a pneumatic tire according to any one of claims 1 to 7.

9. At least one of said plurality of layers (30, 30', 103, 103', 130, 133) is coated with metal, a pneumatic tire according to any one of claims 1 to 8.

10. The pneumatic tire according to any one of claims 1 to 9, characterized in that at least two plural layers (30, 30', 103, 103', 130, 133) include one or more of the same radial thickness, the same radial width, and the same foam strip material.

11. The pneumatic tire according to any one of claims 1 to 10, characterized in that the tire is a bus tire with a rim size of 22.5 inches.

12. The pneumatic tire according to any one of claims 1 to 11, characterized in that the continuous foam noise attenuation foam strip material is composed of one or more of the following materials: polyurethane foam, polyethylene foam, and foamed rubber.

13. A method for manufacturing a foam-damped pneumatic tire, particularly a method for manufacturing a foam-damped pneumatic tire according to any one of claims 1 to 12, the method comprising the steps of: providing a pneumatic tire having at least a tire cavity; attaching a first layer of a continuous foam noise attenuation foam strip material circumferentially to an inner liner (13) of the tire; and attaching a second layer of a continuous foam noise attenuation foam strip material to the first layer.

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