FR3125253A1 - ASSEMBLY WITH IMPROVED UNIFORMITY - Google Patents

Abstract

The invention relates to an assembly (A) of a tire (10) and of at least one additional layer (11) attached to the internal surface (18). The tire (10) comprises a retention device or an electronic component fixed by means for fixing the retention device. The additional layer (11) comprises a functional portion (56) and a compensation portion (58) having an average radial thickness of the additional layer (11) strictly less than the average radial thickness of the functional portion (56). The compensation portion (58) is circumferentially between circumferential ends (60, 62) of the compensation portion (58). The center of gravity (G) of a retention assembly (40) or of an electronic assembly comprising the retention device or the electronic component and the fixing means is positioned circumferentially between the circumferential ends (60, 62) and axially in or to the right of the compensation portion (58). Figure for abstract: Fig 1

Description

ASSEMBLY WITH IMPROVED UNIFORMITY

The present invention relates to an assembly of a tire and at least one additional layer. By tire is meant a tire intended to form an internal cavity by cooperating with a support element of a mounted assembly, this internal cavity being capable of being pressurized to a pressure greater than atmospheric pressure.

We know from the state of the art, in particular from WO2019/186069, a tire comprising a retention device comprising a housing for retaining an electronic component. This retention device is fixed to the internal surface by means for fixing the retention device, for example a layer of an adhesive composition. Such a retention device is capable of retaining the electronic component when the tire is rolling.

Another prior art tire comprises an electronic component fixed directly to the internal surface without it being necessary to use a retention device.

Nevertheless, due to the presence of the retention device, the tire has a lack of uniformity which generates vibrations in the vehicle equipped with the tire. These vibrations are even greater when an electronic component is arranged in the retention device. The same vibrations appear with the electronic organ attached directly to the internal surface.

Generally, a lack of uniformity appears at high speed under the effect of centrifugation and is caused by a localized defect in the tire. Such a localized fault may be an architectural or earth fault. On the one hand, the lack of uniformity appears at speeds all the more reduced as the localized defect is important. On the other hand, the lack of uniformity generates vibrations all the more important as the localized defect is important.

The vibrations associated with the presence of the retention device fixed to the internal surface or the vibrations associated with the presence of the electronic component directly fixed to the internal surface are absolutely not dangerous but nevertheless create unwanted discomfort for the passengers of the vehicle .

The aim of the invention is to reduce, or even eliminate, the discomfort described above.

Thus, the first subject of the invention is an assembly of a tire and of at least one additional layer, the tire comprising an internal surface delimiting at least in part an internal cavity of the tire intended to maintain the tire under pressure, the at least one additional layer being attached to the internal surface,
the tire comprising a retention device capable of retaining an electronic component, the retention device being fixed to the internal surface or to the additional layer by means for fixing the retention device to the internal surface or to the additional layer,
the additional layer comprising:
- a functional portion having a non-zero average radial thickness of the additional layer,
- a compensation portion having an average radial thickness of the additional layer strictly less than the average radial thickness of the functional portion and comprised circumferentially between first and second circumferential ends of the compensation portion,
the center of gravity of a retention assembly comprising the retention device and the means for fixing the retention device being positioned circumferentially between the first and second circumferential ends and axially in or in line with the compensation portion.

The second subject of the invention is an assembly of a tire and of at least one additional layer, the tire comprising an internal surface delimiting at least in part an internal cavity of the tire intended to maintain the tire under pressure, the at least one additional layer being attached to the internal surface, the tire comprising an electronic component, the electronic component being fixed to the internal surface or to the additional layer by means for fastening the electronic component to the internal surface or to the additional layer , the additional layer comprising:
- a functional portion having a non-zero average radial thickness of the additional layer,
- a compensation portion having an average radial thickness of the additional layer strictly less than the average radial thickness of the functional portion and comprised circumferentially between first and second circumferential ends of the compensation portion,
the center of gravity of an electronic assembly comprising the electronic component and the means for fixing the electronic component being positioned circumferentially between the first and second circumferential ends and axially in or in line with the compensation portion.

Thanks to the particular positioning of the retention assembly or of the electronic assembly with respect to the first and second circumferential ends, the assemblies according to the invention have little or no lack of uniformity.

Indeed, the inventors at the origin of the invention identified that the localized defect was a mass defect induced by the localized over-mass of the retention assembly, possibly comprising an electronic component retained in the retention device, or by the localized excess mass of the electronic assembly. In order to reduce or even eliminate this localized excess mass, the invention proposes to compensate for the mass of the retention assembly or of the electronic assembly by reducing locally, here in the compensation portion, the mass of the assembly formed by the additional layer and any means for attaching the additional layer to the internal surface. The slightest difference in mean surface mass between, on the one hand, the compensation portion and the retention assembly optionally comprising an electronic component retained in the retention device or the electronic assembly comprising the electronic component and, on the other hand , the functional portion thus makes it possible to reduce or even eliminate the localized mass defect and therefore to reduce the uniformity defect.

Thus, the invention makes it possible, for a given speed, to reduce the vibrations generated and therefore to gain in comfort. Alternatively or additionally, the invention makes it possible, for a given acceptable level of vibration, to increase the speed of the vehicle without discomfort.

In addition, the invention makes it possible to use relatively heavy electronic components, for example due to a relatively heavy battery, in particular in order to benefit from a relatively high autonomy, without this generating additional discomfort for a given speed. .

The first object of the invention relates to an assembly in which a retention assembly comprises a retention device optionally comprising an electronic component, the retention device making it possible to provide the interface between the optional electronic component and the internal surface or the additional layer.

The second object of the invention relates to an assembly in which the electronic component is directly fixed to the internal surface or to the additional layer without it being necessary to use a retention device.

In the case where the retention device or the electronic component is fixed to the internal surface and not to the additional layer, the compensation portion forms a circumferential discontinuity of the additional layer. Thus, the additional layer has, in the compensation portion, a total absence of additional layer.

The first and second circumferential ends correspond respectively to first and second azimuths corresponding respectively to first and second points of the compensation portion, the first and second points being the points of the circumferentially farthest compensation portion from one another. 'other. Thus, the first and second circumferential ends make it possible to consider the entire circumferential length of the compensation portion.

Each average radial thickness is determined by taking the average of the various thicknesses of the corresponding portion if said portion has a variable thickness, this variation possibly being in the axial and/or circumferential direction. It will be possible in particular, for example, to consider several sections and determine the average of the thicknesses in each section, then take the average of the averages determined for each section. In the case where said portion has a constant thickness, the thickness will simply be measured.

In accordance with the invention, the additional layer is attached to the internal surface. Thus, the additional layer is not molded with the tire but added to the tire once it has been molded and cured. The layer is additional in the sense that, without its presence, the tire can be used normally but without the advantages procured by the additional layer. The additional layer has one or more functions which is or are performed by the functional portion. The compensation portion, if it can also perform all or part of the function or functions, has the main role of compensating for the localized excess mass of the retention assembly or of the electronic assembly as explained above. Of course, the more the compensation portion has significant geometric characteristics, the more impacted will be the function(s) of the additional layer. Those skilled in the art will know how to size the compensation portion according to the desired compromise.

In the case where the average radial thickness of the compensation portion is substantially zero, it is obvious that no solid, liquid or viscoelastic material constitutes the compensation portion.

The tire of the assemblies according to the invention has a substantially toroidal shape around an axis of revolution substantially coinciding with the axis of rotation of the tire. This axis of revolution defines three directions conventionally used by those skilled in the art: an axial direction, a circumferential direction and a radial direction.

The total axial width of the functional portion, and in general of the additional layer, is the maximum axial width measured between the axial ends of the functional portion or of the additional layer. The axial ends form first and second planes substantially perpendicular to the axial direction and passing through first and second points of the functional portion or of the additional layer, the first and second points being the points of the functional portion or of the additional layer axially farthest from each other.

Similarly, the axial width of the compensation portion is the maximum axial width measured between the axial ends of the compensation portion. The axial ends of the compensation portion form first and second planes substantially perpendicular to the axial direction and passing through first and second points of the compensation portion, the first and second points being the points of the axially most distant from each other.

By positioned axially in the compensation portion, it is meant that the center of gravity is positioned axially between the axial ends of the compensation portion. By positioned axially in line with the compensation portion, it is meant that the center of gravity is positioned outside an axial portion between the axial ends of the compensation portion.

By axial direction is meant the direction substantially parallel to the axis of revolution of the tire, that is to say the axis of rotation of the tire.

By circumferential direction is meant the direction which is substantially perpendicular both to the axial direction and to a radius of the tire (in other words, tangent to a circle whose center is on the axis of rotation of the tire).

By radial direction is meant the direction along a radius of the tire, that is to say any direction intersecting the axis of rotation of the tire and substantially perpendicular to this axis.

The median plane of the tire (denoted M) means the plane perpendicular to the axis of rotation of the tire which is located at the axial mid-distance of the two beads and passes through the axial center of the crown reinforcement.

By equatorial circumferential plane of the tire is meant, in a meridian section plane, the plane passing through the equator of the tire, perpendicular to the median plane and to the radial direction. The equator of the tire is, in a meridian section plane (plane perpendicular to the circumferential direction and parallel to the radial and axial directions) the axis parallel to the axis of rotation of the tire and located equidistant between the radially most outside of the tread intended to be in contact with the ground and the radially innermost point of the tire intended to be in contact with a support, for example a rim.

By meridian plane is meant a plane parallel to and containing the axis of rotation of the tire and perpendicular to the circumferential direction.

By radially inner, respectively radially outer, is meant closer to the axis of rotation of the tire, respectively further from the axis of rotation of the tire. By axially inside, respectively axially outside, is meant closer to the median plane of the tire, respectively further from the median plane of the tire.

By bead is meant the radial portion of the tire intended to allow the attachment of the tire to a mounting support, for example a wheel comprising a rim. Thus, each bead is in particular intended to be in contact with a hook of the rim allowing it to be attached.

Any interval of values designated by the expression "between a and b" represents the range of values going from more than a to less than b (i.e. limits a and b excluded) while any interval of values designated by the expression “from a to b” means the range of values going from a to b (that is to say including the strict limits a and b).

The tires of the assemblies of the invention are preferably intended for passenger vehicles, including vehicles called "light trucks" in the United States, or vans as defined within the meaning of the standard of the European Tire and Rim Technical Organization or “ETRTO”, 2020. Such a tire has a section in a meridian section plane characterized by a section height H and a nominal section width SW within the meaning of the standard of the European Tire and Rim Technical Organization or “ETRTO », 2020. The values of SW and H are indicated on the tire sidewall marking, for example as defined according to the ETRTO manual, 2020.

Preferably, the tires for passenger vehicles to which the invention will advantageously be applied are such that the H/S ratio, expressed as a percentage, is at most equal to 90, preferably at most equal to 80 and more preferably at most equal to 70 and is at least equal to 20, preferably at least equal to 30, and the nominal section width SW is at least equal to 155 mm and more preferably at least equal to 175 mm and at most equal to 385 mm, of preferably at most equal to 325 mm. In addition, the hook diameter D, defining the diameter of the mounting rim of the tire, is at least equal to 12 inches, preferably at least equal to 16 inches and at most equal to 24 inches.

In the present application, when reference is made to a circumferential length of a portion of the assembly, this length will be measured as the curvilinear length measured on the outer surface of the tread of the tire of this portion of the assembly. and in the median plane of the tire. When reference is made to a circumferential length of a portion of the additional layer, this length will be measured as the curvilinear length measured on the radially outer surface of this portion of the additional layer and in the median plane of the tire. The length measured on this radially outer surface of the additional layer portion is substantially equal to the length measured on the inner surface of the tire in the median plane of the tire.

In a variant of the first object, the means for fixing the retention device comprise a layer of an adhesive composition radially interposed between the retention device and the internal surface or the additional layer.

In a similar variant of the second object, the means for fixing the electronic component comprise a layer of an adhesive composition radially interposed between the electronic component and the internal surface or the additional layer.

Such a layer of adhesive composition can be a polymeric composition, for example an adhesive of the cyanoacrylate type or even the adhesives described in WO2015165899. It is also possible to envisage using a composition also having functions other than that of the adhesion function, such as for example a self-sealing composition. This is particularly advantageous in the case where the additional layer itself comprises a self-sealing composition.

In another variant of the first object, the means for fixing the retention device comprise a portion of the additional layer arranged radially in line with the retention device.

In a similar variant of the second object, the means for fixing the electronic component comprise a portion of the additional layer arranged radially in line with the electronic component.

This variant will be used in particular, but not exclusively, in the embodiment in which the additional layer comprises a self-sealing layer. Indeed, most self-sealing compositions being sufficiently adherent, it is possible to dispense with using a layer of adhesive composition radially interposed between the retention device or the electronic component and the internal surface or the additional layer. In these other variants of the first and second objects, the portion of the additional layer arranged in line with the retention device or the electronic component consists of the portion in contact with the entirety of the retention device or the electronic component and arranged radially between the retention device or the electronic component and the internal surface.

In yet another variant of the first object, the retention device is integral with the internal surface.

In this variant, the fixing means comprise a material molded simultaneously with the internal surface and the retention device. Here the material of the retention device and the internal surface are identical. Such fastening means are described in particular in application PCT/US2019/068537.

In a first embodiment applicable to the first and second objects, the compensation portion forms a central recess in the additional layer arranged axially between:
- a first axial part of the functional portion,
- a second axial part of the functional portion,
over the entire circumferential length separating the first and second circumferential ends.

The central recess is delimited axially and circumferentially.

The compensation portion extends axially over a non-zero axial width of the additional layer that is strictly less than the total axial width of the additional layer and this, over the entire circumferential length of the compensation portion.

In a first preferred variant of this first embodiment, the center of gravity of the retention assembly or of the electronic assembly is positioned axially in the compensation portion, that is to say axially between the first and second axial ends of the compensation portion. In this first variant, the retention assembly or the electronic assembly is arranged axially in the central recess and allows easy positioning of the retention device or of the electronic component in the central recess during the manufacturing process, either in the case where the step of fixing the retention device or the electronic component is subsequent to the step of fixing the additional layer or in the case where the step of fixing the additional layer is subsequent to the step of fixing the retention device or the electronic component.

In a second variant of this first embodiment, the center of gravity of the retention assembly or of the electronic assembly is positioned axially in line with the compensation portion, that is to say axially outside an axial portion between the first and second axial ends of the compensation portion. In this second variant, the retention assembly or the electronic assembly is arranged axially outside the central recess.

In a second embodiment applicable to the first and second objects, the compensation portion forms a housing in the additional layer and extends axially over the entire axial width of the additional layer and this, over the entire circumferential length separating the first and second circumferential ends.

This embodiment leaves complete freedom on the axial positioning of the retention device without being constrained by the axial positioning of the additional layer. Thus, it will be possible to optimize certain performances of the tire associated with a particular axial positioning of the retention device, as for example in WO2016162345, independently of the axial positioning of the additional layer.

In a first variant of this second embodiment, the center of gravity of the retention assembly or of the electronic assembly is positioned axially in the compensation portion, that is to say axially between the first and second ends axial of the compensation portion which are here located on one or the first and second circumferential ends.

In a second variant of this second embodiment, the center of gravity of the retention assembly or of the electronic assembly is positioned axially in line with the compensation portion, that is to say axially outside an axial portion between the first and second axial ends of the compensation portion which are here located on one or the first and second circumferential ends.

In a third embodiment applicable to the first and second objects, the compensation portion forms a lateral recess in the additional layer arranged axially between:
- an axial part of the functional portion, and
- an axial part of the tire with no additional layer,
and this, over the entire circumferential length separating the first and second circumferential ends.

The lateral recess allows circumferential positioning with respect to the first and second circumferential ends and axial with respect to only one of the axial ends of the compensation portion. Thus, one benefits both from a relatively easy positioning of the retention device while leaving the possibility of optimizing to a certain extent certain performances of the tire associated with a particular axial positioning of the retention device as indicated in particular with reference to the second embodiment previously described.

The compensation portion extends axially over a non-zero axial width of the additional layer that is strictly less than the total axial width of the additional layer over the entire circumferential length of the compensation portion.

In a first variant of this third embodiment, the center of gravity of the retention assembly or of the electronic assembly is positioned axially in the compensation portion, that is to say axially between the first and second ends axial of the compensation portion.

In a second variant of this third embodiment, the center of gravity of the retention assembly or of the electronic assembly is positioned axially in line with the compensation portion, that is to say axially outside an axial portion between the first and second axial ends of the compensation portion.

Optionally and advantageously, in the case where the compensation portion has a substantially zero average radial thickness, the center of gravity of the retention assembly or of the electronic assembly is positioned:
- at a circumferential distance greater than or equal to D1/2, preferably 3 x D1/4 from the first circumferential end,
- at a circumferential distance greater than or equal to D2/2, preferably 3 x D2/4 from the second circumferential end,
D1 and D2 being respectively the circumferential distance between each first and second circumferential end and the middle of the circumferential distance separating the first and second circumferential ends from each other.

Thus, the center of gravity of the retention assembly or of the electronic assembly is brought closer circumferentially as much as possible to the center of gravity of the imaginary portion that would have been removed from the additional layer to form the compensation portion. Thus, the mass of the retention assembly or of the electronic assembly is compensated as precisely as possible in the circumferential direction.

Of course, even more preferentially, the center of gravity of the retention assembly or of the electronic assembly is substantially aligned circumferentially with the middle of the circumferential distance separating the first and second circumferential ends from each other. In other words, the center of gravity of the retention assembly or of the electronic assembly and the middle of the circumferential distance separating the first and second circumferential ends from each other have substantially the same azimuth.

In a variant in which the additional layer intrinsically has insufficient adhesion to the internal surface, the assembly comprises means for fixing the additional layer to the internal surface.

Optionally, the means for fixing the additional layer to the internal surface comprise a layer of an adhesive composition radially interposed between the additional layer and the internal surface. Such a layer of adhesive composition may be a layer of a polymeric composition, in particular an adhesive, for example as described in WO2015165899. It is also possible to envisage using a composition also having other functions, such as for example a self-sealing composition, such as for example described previously with reference to the means for fixing the retention device.

In another variant in which the additional layer intrinsically has sufficient adhesion to the internal surface, the additional layer is in direct contact with the internal surface. Direct contact means that no layer of adhesive composition is radially interposed between the additional layer and the internal surface. This variant will be used in particular, but not exclusively, in the embodiment in which the additional layer comprises a self-sealing layer. Indeed, most self-sealing compositions being sufficiently adherent to the internal surface, it is possible to dispense with using a layer of adhesive composition radially interposed between the additional layer of self-sealing composition and the internal surface.

In a preferred optional configuration, the retention device comprises means for retaining the electronic component on or in the retention device.

In a preferred variant, the means for retaining the electronic component on or in the retention device comprise a housing for retaining the electronic component in the retention device. In this preferred variant, the means for retaining the electronic component on or in the retention device advantageously comprise means for reversibly retaining the electronic component in the retention housing. Preferably, the reversible retention means comprising retention means by elastic clipping of the electronic component in the retention housing.

In another optional variant, the means for retaining the electronic component on or in the retention device comprise means for fixing the electronic component on or in the retention device. In this other variant, the fixing means advantageously comprise means for screwing the electronic component onto or into the retention device.

Optionally, in order to enable the user of the tire to obtain useful parameters, the electronic device is an electronic device for identifying the tire and/or for measuring at least one physical parameter of the internal cavity chosen from among the internal cavity gas pressure and the internal cavity gas temperature.

In one embodiment applicable to the first object, the retention assembly has no electronic component retained by the retention device. In this embodiment, the retention assembly then comprises the retention device, the fixing means but no electronic component retained in the retention device.

Optionally and advantageously, the mass of the retention assembly ranges from 1 g to 10 g, preferably from 2 g to 6 g and more preferably from 3 g to 5 g. Thus, the localized excess mass associated with the presence of the retention device alone and the fastening means is reduced as much as possible. Sufficient mass of the retention assembly guarantees sufficient mechanical strength.

Optionally and preferably, the difference between:
- the mass of a portion of the assembly of circumferential length L comprising a part of the additional layer devoid of the compensation portion, and
- the mass of a portion of the assembly of the same circumferential length L comprising part of the additional layer comprising the compensation portion and the retention assembly,
ranges from 0 g to 16 g, preferably from 3 g to 13 g and more preferably from 6 g to 10 g.

Thus, it is ensured that by subsequently adding an electronic component, the difference between the mass of the portion of the assembly comprising the functional portion and the mass of the portion of the assembly comprising the portion of compensation. We then ensure that when we add an electronic component, we will reduce the localized over-mass without creating a localized under-mass and therefore the localized defect. The difference in masses will be such that, for most speeds permitted on open roads, the vibrations generated will be imperceptible.

In another embodiment applicable to the first object, the retention assembly comprises an electronic member retained by the retention device. In this other embodiment, the retention assembly then comprises the retention device, the fastening means and also the electronic component retained in the retention device.

Optionally and advantageously, the mass of the retention assembly ranges from 7 g to 19 g, preferably from 9 g to 17 g and more preferably from 10 g to 15 g. Analogously to the previous embodiment, the localized excess mass associated with the presence of the retention assembly is reduced as much as possible and sufficient mechanical strength is guaranteed.

Optionally and preferably, the difference, in absolute value, between:
- the mass of a portion of the assembly of circumferential length L comprising a part of the additional layer devoid of the compensation portion, and
- the mass of a portion of the assembly of the same circumferential length L comprising part of the additional layer comprising the compensation portion and the retention assembly,
is less than or equal to 8 g, preferably 5 g and more preferably 2 g.

Thus, the difference between the mass of the portion of the assembly comprising the functional portion and the mass of the portion of the assembly comprising the compensation portion is reduced as much as possible, and this in the presence of the electronic component retained in the device. The localized excess mass and therefore the localized defect are then reduced, in the presence of the electronic component retained in the retention device. The difference in masses is such that, for most speeds permitted on open roads, the vibrations generated are imperceptible.

In one embodiment applicable to the second object, the mass of the electronic assembly ranges from 2 g to 25 g, preferably from 4 g to 20 g and more preferably from 6 g to 15 g.

Optionally and preferably, the difference, in absolute value, between:
- the mass of a portion of the assembly of circumferential length L comprising a part of the additional layer devoid of the compensation portion, and
- the mass of a portion of the assembly of the same circumferential length L comprising a part of the additional layer comprising the compensation portion and the electronic assembly is less than or equal to 8 g, preferably to 5 g and more preferably to 2g.

Analogously to the first object, the difference between the mass of the portion of the assembly comprising the functional portion and the mass of the portion of the assembly comprising the compensation portion and the electronic assembly is reduced as much as possible. The localized excess mass and therefore the localized defect are then reduced. The difference in masses is such that, for most speeds permitted on open roads, the vibrations generated are imperceptible.

In one embodiment of the additional layer, the additional layer comprises a tire cavity sound absorbing foam. Thus, the functional portion here is a cavity noise absorption portion of the tire. The absorption foam makes it possible to reduce or even eliminate the noise generated in the internal cavity of the tire. Examples of absorption foam are in particular described in EP1184207, EP1253025, EP1876038 or even EP3406462.

According to other optional and advantageous characteristics of this embodiment:
- the absorption foam has a density ranging from 10 to 100 kg.m-3,
- the average surface mass of the absorption foam ranges from 0.3 to 3.0 kg.m-2, preferably from 0.5 to 1.5 kg.m-2,
- the circumferential distance separating the first and second circumferential ends is less than or equal to 250 mm, preferably ranges from 50 to 200 mm.

In another embodiment of the additional layer, the additional layer comprises a self-sealing composition. Thus, the functional portion here is a self-sealing portion of the internal cavity of the tire. The self-sealing composition makes it possible, in the event of perforation of the tire due to a piercing object, to close the orifice created by the piercing object under the effect of the internal pressure of the tire. Indeed, under the effect of the internal pressure of the tire, the self-sealing composition is caused to flow into the outward air flow orifice, with a view to sealing it and restoring the inflation gas tightness. Numerous self-sealing compositions have been described in the state of the art, in particular in US4426468, EP1090069, WO99/62998, US4113799, US4115172, US4913209, US5085942, US5295525, FR2955587 and EP2167329.

Other embodiments of the additional layer can be envisaged without departing from the scope of the present invention. Thus, it is entirely possible to use an additional layer comprising a conventional elastomeric composition, for example such as those used for a tread.

In yet another embodiment, the assembly comprises first and second additional layers attached to the internal surface, at least one of the first and second additional layers comprising:
- a functional portion having a non-zero mean radial thickness of said additional layer,
- a compensation portion having an average radial thickness strictly less than the average radial thickness of the functional portion and comprised circumferentially between first and second circumferential ends,
the center of gravity of the retention assembly or of the electronic assembly being positioned circumferentially between the first and second circumferential ends of the compensation portion of said additional layer and axially in the compensation portion of said additional layer or axially at right of the compensation portion of said additional layer.

In a variant of the previous embodiment, the first additional layer comprising:
- a first functional portion having a non-zero mean radial thickness of the first additional layer,
- a first compensation portion having an average radial thickness strictly less than the average radial thickness of the first functional portion and comprised circumferentially between first and second circumferential ends,
the second additional layer comprising:
- a second functional portion having a non-zero mean radial thickness of the second additional layer,
- a second compensation portion having an average radial thickness strictly less than the average radial thickness of the second functional portion and comprised circumferentially between first and second circumferential ends,
the center of gravity of the retention assembly or of the electronic assembly being positioned circumferentially between the first and second circumferential ends of each first and second compensation portion and axially in each first and second compensation portion or axially in line with each first and second portion of compensation.

Advantageously, the or each additional strip extends circumferentially over at least 50% of the circumferential length of the internal surface, preferably at least 75%.

In certain embodiments, it is possible to envisage an assembly comprising several retention assemblies or several fixed electronic components, the center of gravity of at least one of the retention assemblies or one of the fixed electronic components being positioned circumferentially between the first and second ends circumferential and axially in the compensation portion or axially in line with the compensation portion. In certain variants, the additional layer comprising several compensation portions each having an average radial thickness of the additional layer strictly less than the average radial thickness of the functional portion and comprised circumferentially between first and second circumferential ends of said compensation portion, the center of gravity of several of the retention assemblies or of several of the fixed electronic components is positioned circumferentially between the first and second circumferential ends of one of the compensation portions and axially in said compensation portion or axially in line with said compensation portion .

Optionally and advantageously, the center of gravity of the retention assembly or of the electronic assembly is arranged circumferentially outside a circumferential junction zone chosen from:
- a circumferential junction zone between two circumferential ends of an internal sealing layer,
- a circumferential junction zone between two circumferential ends of at least one carcass layer,
- a circumferential junction zone between two circumferential ends of a tread.

Thus, superimposing the localized defect formed by the retention assembly or the electronic assembly on any other localized defects formed by the junction zones described above is preferably avoided. A junction zone can be formed by overlapping or else by butting two ends of the layer or of the strip in question.

In conventional and known manner, a tire comprises a crown, two beads, two sidewalls each connecting each bead to the crown and a carcass reinforcement anchored in each bead, the crown comprising a crown reinforcement and a tread, the carcass extending in each sidewall and in the crown radially internally to the crown reinforcement. The crown reinforcement is arranged radially inside the tread. The tire also conventionally comprises an internal sealing layer delimiting the internal cavity of the tire. In known manner, the carcass reinforcement comprises at least one carcass layer comprising reinforcing elements extending substantially parallel to each other from one axial edge to the other axial edge of the carcass layer. These reinforcing elements are preferably textile or metallic wire elements.

The invention will be better understood on reading the following description, given solely by way of non-limiting example and made with reference to the drawings in which:
- there is a view, in a meridian section plane, of an assembly according to a first embodiment of the first object of the invention,
- there is a side view of the section according to the meridian section plane of the ,
- there is a detail view in section III-III' of the assembly of the ,
- there is a sectional view of a tire retention assembly of the , isolated from the tire,
- there is a sectional view of two portions of the assembly of the ,
- there is a schematic view illustrating different junction zones of different layers of the tire of the ,
- Figures 7 to 10 illustrate steps of a manufacturing method according to a first embodiment of the assembly of the ,
- Figures 11 to 14 illustrate steps of a manufacturing method according to a second embodiment of the assembly of the ,
- Figures 15 to 19 illustrate steps of a manufacturing method according to a third embodiment of the assembly of the ,
- Figures 20 and 21 are views similar to those of Figures 1 and 2 respectively of an assembly according to a second embodiment of the invention,
- Figures 22 to 24 illustrate steps of a manufacturing method according to a first embodiment of the assembly of Figures 20 and 21,
- Figures 25 to 28 illustrate steps of a manufacturing method according to a second embodiment of the assembly of Figures 20 and 21,
- Figures 29 to 37 are views of assemblies according to other embodiments of the invention, and
- there is a view analogous to that of of an assembly in accordance with the second object of the invention.

In the figures, a mark X, Y, Z has been shown corresponding to the usual axial (Y), radial (Z) and circumferential (X) directions respectively of a tire.

In the following description, the measurements taken are taken on an unloaded and uninflated tire, possibly on a section of the tire in a meridian plane.

There is shown in Figures 1 to 3 an assembly A according to a first embodiment of the invention comprising a tire 10 and an additional layer 11. The tire 10 has a substantially toroidal shape around an axis of revolution substantially parallel to the axial direction Y. The tire 10 is intended for a passenger vehicle. In the various figures, the tire 10 is shown in new condition, that is to say not having been driven yet. The tire 10 comprises two sidewalls 30 bearing a marking indicating the size of the tire 10, as well as a speed index and a speed code. In this case, tire 10 has the marking 265/45R20 108Y.

With reference to the , the tire 10 comprises a crown 12 comprising a tread 14 intended to come into contact with the ground during rolling and a crown reinforcement 16 extending in the crown 12 in the circumferential direction X. The tire 10 comprises a layer internal sealing 17 carrying an internal surface 18 at least partially delimiting an internal cavity 19 intended to maintain the tire 10 under pressure once the tire 10 is mounted on a mounting support, for example a wheel.

The crown reinforcement 16 comprises a working reinforcement 20 and a hooping reinforcement 22. The working reinforcement 20 comprises at least one working layer and here comprises two working layers comprising a radially inner working layer 24 arranged radially at inside a radially outer working layer 26 . The hooping reinforcement 22 comprises at least one hooping layer and here comprises a hooping layer 28. The crown reinforcement 16 is surmounted radially by the tread 14. Here, the hooping reinforcement 22, here the layer hooping 28, is arranged radially outside the working reinforcement 20 and is therefore radially interposed between the working reinforcement 20 and the tread 14.

The two sides 30 extend the crown 12 radially inwards. The tire 10 further comprises two beads 32 radially inside the sidewalls 30. Each sidewall 30 connects each bead 32 to the crown 12.

The tire 10 comprises a carcass reinforcement 34 anchored in each bead 32, in this case forms a wrap around a circumferential reinforcement element 33, here a bead wire. The carcass reinforcement 34 extends radially in each sidewall 30 and axially in the crown 12, radially inside the crown reinforcement 16. The crown reinforcement 16 is arranged radially between the tread 14 and the reinforcement carcass 34. The carcass reinforcement 34 comprises at least one carcass layer 36 and here a single carcass layer 36.

The hooping layer 28, the working layers 24, 26 and the carcass layer 36 conventionally comprise textile or metallic wire reinforcement elements.

The tire 10 also comprises a retention assembly 40 comprising a retention device 42 capable of retaining an electronic component 44. The retention assembly 40 here comprises an electronic component 44 retained by the retention device 42. The electronic component 44 allows the identification of the tire as well as the measurement of the gas pressure and the gas temperature of the internal cavity 19. The retention assembly 40 also comprises means 46 for fixing the retention device 42 to the internal surface 18 or to the additional layer 11 and here to the internal surface 18. The fixing means 46 comprise a layer 48 of an adhesive composition radially interposed between the retention device 42 and the internal surface 18. The mass of the retention device 42 ranges from 1 g to 10 g, preferably from 2 g to 6 g and more preferably from 3 g to 5 g and is here equal to 3.5 g. The mass of the electronic component 44 is equal to 8.0 g. The mass of the fixing means 46 is equal to 0.1 g. The mass of the retention assembly 40, that is to say the mass of the retention device 42, of the electronic component 44 and of the means 46 ranges from 7 g to 19 g, preferably from 9 g to 17 g and more preferably from 10 g to 15 g and is here equal to 11.6 g.

With reference to the , the retention device 42 comprises means 43 for retaining the electronic component 44 on or in the retention device 42 comprising a housing 45 for retaining the electronic component 44 in the retention device 42. The retention means 43 comprise means 47 for reversible retention by elastic clipping of the electronic component 44 in the retention housing 45 comprising here a wall of revolution 49A provided with a retention rim 49B made of an elastic material.

The additional layer 11 is attached to the internal surface 18. The additional layer 11 comprises a foam 50 for absorbing the noise of the cavity of the tire 10. The absorption foam 50 has a density equal to 23 kg.m ^-3 thus than an average surface mass equal to 0.69 kg.m ^-2 . Assembly A comprises means 52 for attaching additional layer 11 to internal surface 18 and comprising a layer 54 of an adhesive composition radially interposed between additional layer 11 and internal surface 18. Additional layer 11 comprises a portion 56 functional, here providing the cavity noise absorption function, and a mass compensation portion 58 of the retention assembly 40.

The functional portion 56 has a section of substantially rectangular shape with a non-zero mean radial thickness EpFm and here equal to 30 mm and with a total axial width LaF=150 mm.

Compensation portion 58 is comprised circumferentially between first and second circumferential ends 60, 62 of compensation portion 58 and axially between first and second axial ends 66, 68 of compensation portion 58. Compensation portion 58 extends circumferentially over a circumferential length LoC and over an axial width LaC. Here, LoC is less than or equal to 250 mm, preferably ranges from 50 to 200 mm and here equal to 200 mm and LaC is strictly less than the total axial width LaF of the additional layer 11 over the entire circumferential length LoC of the compensation portion 58. Here LaC=60 mm. The compensation portion 58 forms a central recess 64 in the additional layer 11 arranged axially between a first axial part of the functional portion 70 and a second axial part of the functional portion 72 over the entire circumferential length LoC separating the first and second circumferential ends 60, 62. The average thickness EpCm of additional layer of the compensation portion 58 is strictly less than the average radial thickness EpFm. Here EpCm=0 mm. Thus, the compensation portion 58 forms a circumferential discontinuity.

We represented on the portions 74, 76 of assembly A having the same circumferential length L here equal to 400 mm. Portion 74 comprises part of additional layer 11 devoid of compensation portion 58. Portion 76 comprises part of additional layer 11 comprising compensation portion 58 and retention assembly 40 and here also part of the functional portion 56. The mass M1 of the portion 74 is here equal to 2130.7 g and comprises 2089.3 g of the mass of the tire 10 and 41.4 g of the mass of the additional layer 11. The mass M2 of the portion 76 is equal to 2134 g and comprises 2089.3 g of mass of tire 10, 33.1 g of mass of additional layer 11 and 11.6 g of mass of retention assembly 40. The difference in absolute value |M1- M2| between the masses M1 and M2 is less than or equal to 8 g, preferably to 5 g and here equal to 3.3 g. By lengthening or widening the compensation portion 58, one could imagine obtaining a difference |M1-M2| less than or equal to 2 g.

With reference to the schematic figure 6, the center of gravity G of the retention assembly 40 identified circumferentially by the azimuth AzG is arranged circumferentially outside the following circumferential junction zones: a circumferential junction zone between two circumferential ends of an internal sealing layer 17 identified circumferentially by the azimuth AzI, a circumferential junction zone between two circumferential ends of the carcass layer 36 circumferentially identified by the azimuth AzC and a circumferential junction zone between two circumferential ends of the strip bearing 14 identified circumferentially by the azimuth AzR.

With reference to the , the center of gravity G of the retention assembly 40 is positioned circumferentially between the first and second circumferential ends 60, 62 and axially in the compensation portion 58, that is to say axially between the first and second axial ends 66, 68 of the compensation portion 58. More specifically, the center of gravity G of the retention assembly 40 is positioned at a circumferential distance greater than or equal to D1/2, preferably 3D1/4 from the first circumferential end 60 and at a circumferential distance greater than or equal to D2/2, preferably 3D2/4 from the second circumferential end 62 with D1 and D2 being respectively the circumferential distance between each first and second circumferential end 60, 62 and the middle of the circumferential distance LoC separating the first and second circumferential ends 60, 62 from each other. Here, the center of gravity G of the retention assembly 40 is substantially aligned circumferentially with the middle of the circumferential distance LoC separating the first and second circumferential ends 60, 62 from each other. Furthermore, the center of gravity G of the retention assembly 40 is substantially aligned axially with the middle of the axial distance LaC separating the first and second axial ends 66, 68 from each other.

We will now describe a manufacturing method according to a first embodiment of the assembly A according to the first embodiment with reference to Figures 7 to 10 numbered in chronological order.

As illustrated on the , there is first of all an assembly A consisting of the single tire 10.

Prior to the steps of fixing the additional layer 11 and the retention device 42 described below, the method comprises a step of determining the azimuths AzI, AzR and AzC.

Then, with reference to the , prior to the step of fixing the additional layer 11 described below, the method comprises a step of applying an adhesive composition to the internal surface 18 so as to form the layer 54 of the adhesive composition intended to be radially interposed between the additional layer 11 and the internal surface 18. The step of applying the adhesive composition comprises a step of extruding the adhesive composition carried out via extrusion means (not shown) and a step rotation of the tire 10 relative to the extrusion means carried out during the extrusion step. As illustrated on the , the extrusion step is carried out so as to affix a discontinuous strip or bead 78 circumferentially. The circumferential discontinuity 80 of the strip or cord 78 is intended to coincide at least partially with the compensation portion 58 of the additional strip 11.

With reference to the , the method comprises a step of fixing the additional layer 11 to the internal surface 18 carried out so that, once the additional layer 11 fixed to the internal surface 18, the additional layer 11 comprises the functional portion 56 and the compensation portion 58. Here, the step of attaching the additional layer 11 comprises a step of winding an additional strip 82 over at most one circumferential turn, here exactly one circumferential turn, inside the internal cavity 19. The additional strip 82 has a circumferential length slightly greater than the circumferential length of the internal surface 18, a width equal to LaF and an average thickness equal to EpFm. Before the fixing step, the method comprises a step of cutting out a portion of the additional strip 82 so as to provide the compensation portion 58, in this case a rectangular portion of the additional strip 82 having a length circumferential LoC, a width equal to LaC and an average thickness EpFm. In order to provide the central recess forming the compensation portion 58, the cutting step is carried out so that the additional strip 82 is discontinuous circumferentially over a non-zero axial width LaC strictly less than the total axial width LaF of the strip strip 82. The cutting step thus includes a step of central hollowing out the additional strip 82.

Rather than a winding step, a step of fixing the additional layer 11 could be envisaged comprising a step of affixing the additional layer 11 in contact with the internal surface 18 by means of the fixing means 52 and, prior to the affixing step, a step of radial compression of the additional layer 11 in the form of a continuous ring as described in EP1574360.

Prior to the step of fixing the retention device 42 described below, the method comprises a step of applying an adhesive composition to the internal surface 18 and to a surface of the retention device 42 so as to form the layer 48 of the adhesive composition intended to be radially interposed between the retention device 42 and the internal surface 18. Prior to the step of fixing the device 42 described below, the method comprises a step of fixing the electronic component 44 in the retention device 42.

Still prior to the step of fixing the retention device 42, the method comprises a step of determining a reference azimuth, a function here of the azimuth of each first and second circumferential end 60, 62 as well as a step of determining a reference axial position depending on the axial position of each first and second axial end 66, 68. Then, the method comprises a step of determining a positioning azimuth AzG of the center of gravity G of the retention assembly 40 with respect to the reference azimuth as well as a step of determining an axial position of the center of gravity G of the assembly of gravity 40 with respect to the axial position of reference.

Then, with reference to the , the method comprises a step of fixing the retention device 42 to the internal surface 18 by means of the fixing means 46, here of the layer 48. This step of fixing the retention device 42 is therefore subsequent to the step fixing the additional layer 11.

The steps of fixing the additional layer 11 and the retention device 42 are carried out so that, once the additional layer 11 fixed to the internal surface 18 and the retention device 42 fixed to the internal surface 18, the center of gravity G of the retention assembly 40 is arranged circumferentially between the first and second circumferential ends 60, 62 and axially in the compensation portion 58, that is to say, in this first embodiment, axially between the first and second axial ends 66, 68.

In a variant, it is possible to imagine affixing a circumferentially continuous strip or bead 78 so as to form the layer 48 of the adhesive composition intended to be radially interposed between the retention device 42 and the internal surface 18 in addition to the layer 54 of the adhesive composition intended to be radially interposed between the additional layer 11 and the internal surface 18. Thus, in this variant, the fixing means 46 and the fixing means 52 comprise the same adhesive composition radially interposed between the additional layer 11, the retainer 42 and inner surface 18.

We will now describe a manufacturing method according to a second embodiment of the assembly A according to the first embodiment with reference to Figures 11 to 14 numbered in chronological order.

Unlike the method according to the first embodiment, and in particular in FIGS. 12 to 14, the step of fixing the additional layer 11 is subsequent to the step of fixing the retention device 42. In particular, prior to the step of fixing the additional layer 11, the method comprises a step of determining a reference azimuth depending on the azimuth AzG of the center of gravity G of the retention assembly 40 as well as a step of determining the an axial position of reference depending on the axial position of the center of gravity G of the retention assembly 40. Then the method comprises a step of determining a positioning azimuth of each first and second circumferential end 60, 62 with respect to at the reference azimuth AzG as well as a step of determining an axial position of each first and second axial end 66, 68 relative to the reference axial position.

As illustrated in FIGS. 12 and 13, in this second embodiment, the step of applying the adhesive composition to the internal surface 18 so as to form the layer 54 of the adhesive composition intended to be radially interposed between the layer additional 11 and the internal surface 18 is posterior to the step of fixing the retention device 42. Thus, it is possible to position the discontinuity 80 circumferentially and axially as a function of the reference azimuth AzG and of the reference axial position of the center of gravity G, the determination of which is made before the step of applying the adhesive composition to the internal surface 18.

We will now describe a manufacturing method according to a third embodiment of the assembly A according to the first embodiment with reference to Figures 15 to 19 numbered in chronological order.

Just as in the first embodiment, the step of fixing the retention device 42 is subsequent to the step of fixing the additional layer 11. But unlike the method according to the first embodiment, the method here comprises , prior to the step of cutting out the portion of the additional strip 82, here designated by the reference 84, so as to provide the compensation portion 58, a step of providing a pre-cut line 86 delimiting the compensation portion 58.

We will now describe an assembly according to a second embodiment of the invention with reference to Figures 20 and 21. The elements similar to the first embodiment are designated by identical references.

Unlike the assembly A according to the first embodiment, the compensation portion 58 of the assembly A according to the second embodiment forms a housing 64 in the additional layer 11 extending axially over the entire width axial length LaF of the additional layer 11 over the entire circumferential length LoC separating the first and second circumferential ends 60, 62. In this second embodiment, the center of gravity G of the retention assembly 40 is positioned axially in the compensation portion 58, that is to say axially between the axial ends 66, 68 of the compensation portion 58. It could also be envisaged that the center of gravity G of the retention assembly 40 be positioned axially at the outside of an axial portion 90 between the axial ends 66, 68 of the compensation portion 58, that is to say axially in line with the compensation portion 58. In addition, the addi 11 comprises here not a foam 50 for absorbing cavity noise but a self-sealing composition 51. It could alternatively be considered that the additional layer 11 is a foam 50 for absorbing cavity noise. Thus, due to its properties of adhesion to the internal surface 18, the additional layer is in direct contact with the internal surface 18, that is to say that no layer of adhesive composition is radially interposed between the additional layer 11 and the inner surface 18.

We will now describe a manufacturing method according to a first embodiment of the assembly A according to the second embodiment with reference to Figures 22 to 24 numbered in chronological order. This method is similar to the method according to the first embodiment described with reference to Figures 7 to 10 insofar as the step of fixing the retention device 42 is subsequent to the step of fixing the additional layer 11.

Nevertheless, taking into account the housing 64, the step of cutting out the additional strip 82 is here carried out so that the additional strip 82 is discontinuous circumferentially over the entire axial width of the additional strip LaF. The cutting step thus comprises a step of reducing the length of the additional strip 82 so that the additional strip 82 has a length, here 204 cm, strictly less than the circumferential length of the internal surface 18, here equal to 224 cm. .

It will also be noted that unlike the methods described with reference to FIGS. 7 to 19, the additional layer 11 is fixed directly in contact with the internal surface 18.

We will now describe a manufacturing method according to a second embodiment of the assembly A according to the second embodiment with reference to Figures 25 to 27 numbered in chronological order and to the .

Unlike the embodiments of the methods described with reference to the preceding figures, the step of fixing the additional layer 11 comprises a step of winding a strip or a cord 92 over several circumferential turns 94 at the inside the internal cavity 18 and here on 5 circumferential turns 94. In FIGS. 25 to 27, the winding of the first circumferential turn and of part of the second circumferential turn has been shown. One could also consider the simultaneous winding of the circumferential turns 94 so as to reduce the duration of the winding step.

Each circumferential turn 94 has the general shape of a ring which is distinct from the ring(s) formed by the other circumferential turn(s) 94 as shown in the . It could just as well be envisaged that the circumferential turns 94 form a spiral formed by tracanage and that the adjacent circumferential turns overlap axially in part on each other.

In order to form the compensation portion 58 during the winding step, each circumferential turn 94 is discontinuous circumferentially. In a variant not illustrated, one could imagine on the contrary that the circumferential turns are circumferentially continuous and that, in order to provide the compensation portion 58 after the winding step, the method comprises a step of cutting the wound strip or of the coiled cord 92. In yet another variant, one could imagine that some of the circumferential turns 94 and not all of the circumferential turns 94 are circumferentially discontinuous.

We will now describe assemblies A according to other embodiments with reference to the to 37. Elements similar to those described in the previous embodiments are denoted by identical references. In these embodiments, the additional layer 11 may indifferently comprise a tire cavity noise absorption foam 50 or else a self-sealing composition 51. In the description of these embodiments, we will limit ourselves, for reasons concisely, to the description of the specific elements and steps that differentiate these embodiments from the other embodiments previously described.

In the embodiment illustrated in the , the compensation portion 58 forms a lateral recess in the additional layer 11 arranged axially between an axial part 70 of the functional portion 56 and an axial part 71 of the tire 10 devoid of additional layer 11, and this over the entire circumferential length LoC separating the first and second circumferential ends 60, 62.

The compensation portion 58 extends axially over a non-zero axial width LaC of the additional layer 11 strictly less than the total axial width LaF of the additional layer 11 over the entire circumferential length LoC of the compensation portion 58.

In the embodiment illustrated in the , the median plane of the additional strip 11 is substantially coincident with the median plane M of the tire 10.

In the embodiment illustrated in the , the central recess forming the compensation portion 58 has the general shape of a cylinder of height equal to the mean radial thickness EpFm of the functional portion 56.

In the embodiment illustrated in the , assembly A comprises first and second additional layers 11A, 11B attached to internal surface 18. First additional layer 11A comprises a functional portion 56A as well as a circumferential discontinuity 64A comprised circumferentially between circumferential ends 61, 63 of the discontinuity 64A of the first additional layer 11A. The center of gravity G of the retention assembly 40 being positioned circumferentially outside the discontinuity 64A, the discontinuity 64A has no function of compensation for the localized excess mass of the retention assembly 40. The second additional layer 11B comprises a functional portion 56B having a non-zero average radial thickness of the second additional layer 11B and a compensation portion 58B having an average radial thickness strictly less than the average radial thickness of the functional portion 56B. Just as in the previous embodiments, the compensation portion 58B is comprised circumferentially between the first and second circumferential ends 60B, 62B. And just as in the previous embodiments, the center of gravity G of the retention assembly 40 is positioned circumferentially between the first and second circumferential ends 60B, 62B and axially in or to the right of the compensation portion 58B, here in the compensating part 58B.

In the embodiment illustrated in the , unlike the embodiment of the , the first additional layer 11A comprises, in addition to a functional portion 56A having a non-zero average radial thickness of the first additional layer 11A, a compensation portion 58A having an average radial thickness strictly less than the average radial thickness of the functional portion 56A and comprised circumferentially between first and second circumferential ends 60A, 62A.

The center of gravity G of the retention assembly 40 being positioned circumferentially between the first and second circumferential ends 60A, 62A of the compensation portion 58A and between the first and second circumferential ends 60B, 62B of the compensation portion 58B and axially in line with each compensation portion 58A, 58B, each compensation portion 58A, 58B has a function of compensation for the localized excess mass of the retention assembly 40.

In the embodiment illustrated in the , it is illustrated how to determine the first and second circumferential ends 60, 62 in this specific case but also in all cases. The first and second circumferential ends 60, 62 correspond respectively to first and second azimuths Az1, Az2 corresponding respectively to first and second points T1, T2 of the compensation portion 58, the first and second points T1, T2 being the points of the compensation portion 58 circumferentially furthest from each other. The points T3, T4 represented on the are certainly points of the compensation portion 58 but are not the points of the compensation portion 58 circumferentially farthest from each other. This determination of the circumferential ends is consistent with that used in the previously described embodiments.

In the embodiment illustrated in the , the additional layer 11 has a section whose width is variable and illustrates how to generally determine the first and second circumferential ends 60, 62 as explained with reference to , the first and second axial ends 66, 68 of the compensation portion 58 and the first and second axial ends 86, 88 of the functional portion 56.

The first and second axial ends 66, 68 form first and second planes Q1, Q2 substantially perpendicular to the axial direction and passing through first and second points P1, P2 of the compensation portion 58, the first and second points P1, P2 being the points of the compensation portion 58 axially farthest from each other. The points P3, P4 represented on the certainly axially delimit the compensation portion 58 but are not the points of the compensation portion 58 axially farthest from each other.

The first and second axial ends 86, 88 form first and second planes Q1', Q2' substantially perpendicular to the axial direction and passing through first and second points P1', P2' of the functional portion 56, the first and second points P1′, P2′ being the points of the functional portion 56 that are axially farthest from each other. The points P3', P4' represented on the certainly axially delimit the functional portion 56 but are not the points of the functional portion 56 axially farthest from each other.

This determination of the circumferential and axial ends is consistent with that used in the previously described embodiments.

In the embodiment illustrated in FIGS. 36 and 37, unlike the previous embodiments, the mean radial thickness EpCm of the compensation portion 58 is not substantially zero and here EpCm=1 mm whereas EpFm=4 mm . In addition, the retention device 42 is fixed not to the internal surface 18 but to the additional layer 11. Indeed, due to the very good intrinsic adhesion of the additional layer 11 of this embodiment, for example when the additional layer 11 comprises a self-sealing composition, the fixing means 46 of the retention device 42 comprise a portion 96 of the additional layer 11 arranged radially in line with the retention device 42. On the , the two circumferential ends 98, 99 of the portion 96 have been shown.

In this embodiment and unlike the previous embodiments, the additional layer 11 intrinsically having sufficient adhesion to the internal surface 18, the additional layer 11 is fixed directly in contact with the internal surface during the manufacturing process.

An embodiment of the second object of the invention will now be described with reference to the . Elements similar to the embodiments are designated by identical references.

In assembly A of this embodiment, the retention assembly is replaced by an electronic assembly 41, that is to say an electronic component 44 fixed directly to the internal surface 18 or directly to the additional layer 11 and fixing means 46 without it being necessary to use a retention device to retain the electronic component 44.

In such an assembly A, the mass of the electronic assembly 41, that is to say the mass of the electronic component 44 and the fixing means 46, ranges from 2 g to 25 g, preferably from 4 g to 20 g and more preferably from 6 g to 15 g and the difference, in absolute value, between:
- the mass of a portion of the assembly A of circumferential length L comprising a part of the additional layer 11 devoid of the compensation portion 58, and
- the mass of a portion of the assembly A of the same circumferential length L comprising part of the additional layer 11 comprising the compensation portion 58 and the electronic assembly 41
is less than or equal to 8 g, preferably 5 g and more preferably 2 g.

Here, the mass of the electronic assembly 41 is equal to 8.1 g and the difference |M1-M2| is equal to 0.2 g.

The assembly shown in the is obtained by a process similar to those previously described. Nevertheless, unlike the methods previously described, the method does not comprise a step of fixing the retention device 42 to the internal surface 18 or to the additional layer 11 by means of the fixing means 46 but, in the absence of retention device 42, a step of fixing the electronic component 44 to the internal surface 18 or to the additional layer 11, here to the internal surface 18, by means of the fixing means 46 of the electronic component 44 to the internal surface 18 or to the additional layer 11, here to the internal surface 18.

Similarly, the steps of fixing the additional layer 11 and the electronic component 44 are carried out so that, once the additional layer 11 fixed to the internal surface 18 and the electronic component 44 fixed to the internal surface 18 or to the additional layer 11, the center of gravity G of the electronic assembly 41 comprising the electronic component 44 and the fixing means 46 of the electronic component 44 is arranged circumferentially between the first and second circumferential ends 60, 62 and axially in or in line with the compensation portion 58.

The invention is not limited to the embodiments previously described.

Indeed, with the exception of the embodiment described with reference to the , all the previous embodiments can also be envisaged even in the absence of an electronic component retained in the retention device. Thus, it is possible to envisage an assembly in which the retention assembly has no electronic component retained by the retention device. In such an assembly, the mass of the retention assembly ranges from 1 g to 10 g, preferably from 2 g to 6 g and more preferably from 3 g to 5 g. For example, in a variant of the first embodiment in which the mass of the electronic component 44 is removed, the mass of the retention assembly is equal to 3.6 g. The difference M1-M2 in the absence of electronic device 44 ranges from 0 g to 16 g, preferably from 3 g to 13 g and is here equal to 4.7 g so that, if a user subsequently adds a device electronics 44, the difference |M1-M2| in the presence of the electronic device 44 remains weak enough to have an imperceptible lack of uniformity. By lengthening or widening the compensation portion 58, one could imagine obtaining a difference M1-M2 ranging from 6 g to 10 g.

Claims (15)

Assembly (A) of a tire (10) and of at least one additional layer (11), the tire (10) comprising an internal surface (18) delimiting at least in part an internal cavity (19) of the tire (10 ) intended to maintain the tire (10) under pressure, the at least one additional layer (11) being attached to the internal surface (18), the tire (10) comprising a retention device (42) capable of retaining an electronic component (44), the retention device (42) being fixed to the internal surface (18) or to the additional layer (11) by means (46) for fixing the retention device (42) to the internal surface (18) or to the additional layer (11), the additional layer (11) comprising:
- a functional portion (56) having a non-zero mean radial thickness (EpFm) of the additional layer (11),
- a compensation portion (58) having an average radial thickness (EpCm) of the additional layer (11) strictly less than the average radial thickness (EpFm) of the functional portion (56) and comprised circumferentially between first and second ends circumferential (60, 62) of the compensation portion (58),
the center of gravity (G) of a retention assembly (40) comprising the retention device (42) and the attachment means (46) of the retention device (42) being positioned circumferentially between the first and second circumferential ends ( 60, 62) and axially in or in line with the compensation portion (58). Assembly (A) of a tire (10) and of at least one additional layer (11), the tire (10) comprising an internal surface (18) delimiting at least in part an internal cavity (19) of the tire (10 ) intended to maintain the tire (10) under pressure, the at least one additional layer (11) being attached to the internal surface (18), the tire (10) comprising an electronic component (44), the electronic component (44 ) being fixed to the internal surface (18) or to the additional layer (11) by fixing means (46) of the electronic component (44) to the internal surface (18) or to the additional layer (11),
the additional layer (11) comprising:
- a functional portion (56) having a non-zero mean radial thickness (EpFm) of the additional layer (11),
- a compensation portion (58) having an average radial thickness (EpCm) of the additional layer (11) strictly less than the average radial thickness (EpFm) of the functional portion (56) and comprised circumferentially between first and second ends circumferential (60, 62) of the compensation portion (58),
the center of gravity (G) of an electronic assembly (41) comprising the electronic component (44) and the fixing means (46) of the electronic component (44) being positioned circumferentially between the first and second circumferential ends ( 60, 62) and axially in or in line with the compensation portion (58). Assembly (A) according to claim 1 or 2, in which:
- the fixing means (46) of the retention device (42) comprise a layer (48) of an adhesive composition radially interposed between the retention device (42) and the internal surface (18) or the additional layer (11) , Or
- the fixing means (46) of the electronic component (44) comprise a layer (48) of an adhesive composition radially interposed between the electronic component (44) and the internal surface (18) or the additional layer (11 ). Assembly (A) according to claim 1 or 2, in which:
- the fixing means (46) of the retention device (42) comprise a portion of the additional layer (11) arranged radially in line with the retention device (42), or
- the fixing means (46) of the electronic component (44) comprise a portion of the additional layer (11) arranged radially in line with the electronic component (44). An assembly (A) according to claim 1, wherein the retainer (42) is integral with the inner surface (18). Assembly (A) according to any one of Claims 1 to 5, in which the compensation portion (58) forms a central recess in the additional layer (11) arranged axially between:
- a first axial part (70) of the functional portion (56),
- a second axial part (72) of the functional portion (56),
over the entire circumferential length (LoC) separating the first and second circumferential ends (60, 62). Assembly (A) according to any one of Claims 1 to 5, in which the compensation portion (58) forms a recess in the additional layer (11) extending axially over the entire axial width (LaF) of the additional layer (11) over the entire circumferential length (LoC) separating the first and second circumferential ends (60, 62). Assembly (A) according to any one of Claims 1 to 5, in which the compensation portion (58) forms a lateral recess in the additional layer (11) arranged axially between:
- an axial part (70) of the functional portion (56), and
- an axial part (71) of the tire (10) without any additional layer (11),
over the entire circumferential length (LoC) separating the first and second circumferential ends (60, 62). Assembly (A) according to Claim 1 taken in combination with any one of Claims 3 to 8, in which the retention assembly (40) has no electronic component (44) retained by the retention device (42) . Assembly (A) according to the preceding claim, in which the difference between:
- the mass (M1) of a portion (74) of the assembly (A) of circumferential length L comprising a part of the additional layer (11) devoid of the compensation portion (58), and
- the mass (M2) of a portion (76) of the assembly (A) of the same circumferential length L comprising a part of the additional layer (11) comprising the compensation portion (58) and the retention assembly ( 40)
ranges from 0 g to 16 g, preferably from 2 g to 14 g and more preferably from 5 g to 11 g. Assembly (A) according to Claim 1 taken in combination with any one of Claims 3 to 8, in which the retention assembly (40) comprises an electronic member (44) retained by the retention device (42). Assembly (A) according to the preceding claim, in which the difference, in absolute value, between:
- the mass (M1) of a portion (74) of the assembly (A) of circumferential length L comprising a part of the additional layer (11) devoid of the compensation portion (58), and
- the mass (M2) of a portion (76) of the assembly (A) of the same circumferential length L comprising a part of the additional layer (11) comprising the compensation portion (58) and the retention assembly ( 40)
is less than or equal to 8 g, preferably 5 g and more preferably 2 g. Assembly (A) according to Claim 2 taken in combination with any one of Claims 3 to 8, in which the difference, in absolute value, between:
- the mass (M1) of a portion (74) of the assembly (A) of circumferential length L comprising a part of the additional layer (11) devoid of the compensation portion (58), and
- the mass (M2) of a portion (76) of the assembly (A) of the same circumferential length L comprising part of the additional layer (11) comprising the compensation portion (58) and the electronic assembly (41 )
is less than or equal to 8 g, preferably 5 g and more preferably 2 g. Assembly (A) according to any one of Claims 1 to 13, in which the additional layer (11) comprises a foam (50) for absorbing the sound of the cavity (19) of the tire (10). Assembly (A) according to any one of Claims 1 to 13, in which the additional layer (11) comprises a self-sealing composition (51).