Tyre comprising a durable stiffening structure comprising common anchoring points

Abstract

The invention relates to a tyre (10) comprising a stiffening structure (52) comprising first main and complementary stiffening elements (54C, 54D) extending continuously in the toroidal cavity (36) from the first sidewall (30A) and / or bead (32A) to the crown (12). The tyre (10) comprises a first radially inner anchoring point (56C) common to the first main and complementary stiffening elements (54C, 54D) in the first sidewall (30A) and / or bead (32A) and a first radially outer anchoring point (58C) common to the first main and complementary stiffening elements (54C, 54D) in the crown (12).

Description

Tyre comprising a durable stiffening structure comprising common anchoring points Technical fieldThe present invention relates to a tyre, notably for a passenger vehicle. The term “tyre” should be understood to mean a tyre casing intended to form a cavity by interacting with a mounting support, for example a rim, this cavity being capable of being pressurized to a pressure greater than atmospheric pressure. A tyre has a structure of substantially toroidal shape exhibiting symmetry of revolution about a main axis of the tyre, this main axis being coincident with the axis of rotation of the tyre.Prior artA tyre intended to be fitted to a passenger vehicle is known in the prior art and described in WO2020 / 128225. The tyre described comprises a crown extended radially inwards on either side of the midplane of the tyre respectively by first and second sidewalls and then by first and second beads intended to come into contact with a mounting support, for example a rim. Each first and second bead comprises a circumferential reinforcing element intended to allow the tyre to be attached to the mounting support.The tyre comprises an inner surface which delimits a toroidal inflation cavity of the tyre once the tyre is mounted on the mounting support.The tyre described in WO2020 / 128225 comprises a stiffening structure comprising first stiffening elements extending continuously in the toroidal cavity from the first bead to the crown and second stiffening elements extending continuously in the toroidal cavity from the second bead to the crown.Each first and second stiffening element is rigidly secured to each bead from which it extends by a bead interface between the stiffening element and a portion of the inner surface of the bead. Likewise, each first and second stiffening element is rigidly secured to the crown of the tyre by a crown interface between the stiffening element and a portion of the inner surface of the crown. Each bead and crown interface comprises a cushion made of an elastomer compound, positioned between the stiffening element and the corresponding portion of the inner surface.It was found that each bead and crown interface was subjected to tensile stress. Such interfaces are sensitive to repeated stresses which can lead to premature separation between the stiffening elements and the inner surface of the bead and / or the inner surface of the crown and therefore to premature wear-out of the stiffening structure.The durability of the tyre described in WO2020 / 128225 has been improved in WO2022 / 200715 and WO2022 / 200717 by anchoring each first and second stiffening element in the internal structure of the tyre. Nevertheless, the durability of the tyre described in WO2022 / 200715 and WO2022 / 200717, in particular the durability of the anchoring of the first and second stiffening elements in each first sidewall and / or bead and second sidewall and / or bead, although greatly improved compared to that of the tyre described in WO2020 / 128225, could be improved.The invention aims to improve the durability of the stiffening structure described in WO2020 / 128225, WO2022 / 200715 and WO2022 / 200717.Summary of the inventionThe invention relates to a tyre comprising a crown, first and second sidewalls each extending the crown radially inwards, first and second beads respectively extending the first and second sidewalls radially inwards, the tyre being provided with an inner surface delimiting a toroidal inflation cavity of the tyre, the tyre comprising a stiffening structure comprising:- at least a first main stiffening element extending continuously in the toroidal cavity from at least the first sidewall and / or bead to at least the crown, and being anchored in the first sidewall and / or bead and in the crown, - at least a first complementary stiffening element, distinct from said first main stiffening element, extending continuously in the toroidal cavity from at least the first sidewall and / or bead to at least the crown, and being anchored in the first sidewall and / or bead and in the crown,the tyre comprises a first radially inner common anchoring point common to said first main and complementary stiffening elements in the first sidewall and / or bead and a first radially outer common anchoring point common to said first main and complementary stiffening elements in the crown. As explained below, the invention works when it is applied to just one side of the tyre, in this instance at least on the side comprising the first sidewall and / or bead. According to advantageous embodiments, the invention is also applied to both sides of the tyre but this is not necessary to carry out the invention. In the present patent application, the use of the qualifier "first" is intended, in the absence of any other obvious interpretation, to associate the element qualified as "first" with the first sidewall and / or bead. Likewise, the use of the qualifier "second" is intended, in the absence of any other obvious interpretation, to associate the element qualified as "second" with the second sidewall and / or bead.Advantageously, the first sidewall and / or bead is arranged on the same side of the midplane of the tyre as the outer side of the tyre. Thus, the stiffening structure acts on the side of the tyre most subjected to stress loadings in the event of cornering stress loadings. Inner and outer sides mean that the tyre is designed such that one of its sides is arranged on the inside and the other one of its sides is arranged on the outside. This orientation imposed by the tyre manufacturer makes it possible to ensure that the tyre operates as expected. Specifically, the mounting of a tyre with an orientation different from the one imposed by the manufacturer could result in suboptimal behaviour of the vehicle. "Outer side" refers to the side of the tyre that is entirely visible from the outside of the vehicle when the tyre is fitted on the vehicle. "Inner side" refers to the side of the tyre that faces the wheel arch of the vehicle on which it is fitted. Generally, the tyre has a marking indicating the inner side and the outer side.In a preferred embodiment in which the stiffening structure performs its function on either side of the midplane of the tyre, thus ensuring homogeneous tyre behaviour, the stiffening structure comprises:- at least a second main stiffening element extending continuously in the toroidal cavity from at least the second sidewall and / or bead to at least the crown, and being anchored in the second sidewall and / or bead and in the crown, - at least a second complementary stiffening element, distinct from said second main stiffening element, extending continuously in the toroidal cavity from at least the second sidewall and / or bead to at least the crown, and being anchored in the second sidewall and / or bead and in the crown, the tyre comprises a second radially inner common anchoring point common to said second main and complementary stiffening elements in the second sidewall and / or bead and a second radially outer common anchoring point common to said second main and complementary stiffening elements in the crown.The presence of the main and complementary stiffening elements makes it possible to reduce local stresses on the one hand between the stiffening structure and the sidewall and / or bead at each radially inner common anchoring point and on the other hand between the stiffening structure and the crown at each radially outer common anchoring point, and therefore to improve the durability of the stiffening structure. Thus, such anchoring of the stiffening structure is significantly more robust than the bead interfaces described in WO2020 / 128225 or the anchoring described in WO2022 / 200715 and WO2022 / 200717, as shown by the comparative tests described at the end of this description. The inventors behind the invention postulate that with common anchoring points, the local stresses between the stiffening structure and the sidewall and / or bead and the crown are sufficiently reduced to avoid damaging the stiffening structure at the anchoring of the stiffening structure in the sidewall and / or bead and the crown. Furthermore, the presence of the radially inner and outer anchoring points makes it possible to maximize the number of main and complementary stiffening elements without necessarily providing too many radially inner and outer anchoring points, something which would weaken the stiffening structure and thus reduce the durability of the tyre, contrary to the desired effect."Anchored in a sidewall and / or bead and in the crown" means that the stiffening structure or stiffening element penetrates the sidewall and / or bead and the crown, in other words the stiffening structure or stiffening element passes through the inner surface so as to be anchored in a sidewall and / or bead and in the crown.An anchoring point is referred to as "common" because the main and complementary stiffening elements that pass through this common anchoring point are in contact with one another at this common anchoring point. Thus, the first main and complementary stiffening elements are in contact with one another at the first radially inner and outer common anchoring points. Likewise, the second main and complementary stiffening elements are in contact with one another at the second radially inner and outer common anchoring points.The toroidal inflation cavity is intended to be pressurized with an inflation gas once the tyre has been mounted on a mounting support, usually a rim.Among other advantages, the stiffening structure makes it possible to simultaneously increase the radial stiffness, axial stiffness and cornering stiffness of the tyre compared to a conventional tyre not comprising a stiffening structure, but also compared to tyres comprising other stiffening structures, such as that described in WO2017 / 005713. By increasing the radial stiffness, the stiffening structure limits the radial deformation of the crown during running, and in particular the camber, in other words the radial deformation, on the opposite side to the contact patch of the tread surface in contact with the ground. Thus, during running of the tyre, when the wheel turns, the stiffening structure makes it possible to limit the amplitude of the cyclic deformations of the tyre, and in particular of its tread, and therefore to limit the resultant dissipation of energy, thereby helping to reduce rolling resistance. Furthermore, under radial stress loading, the value of the contact patch is not modified, which makes it possible to keep the same grip performance as for the tyre described in WO2017 / 005713. By increasing the axial stiffness and cornering stiffness, the stiffening structure will help improve handling under transverse stress loading, for example when running with drift thrust. Furthermore, under transverse stress loading, the contact patch ensures a more uniform distribution of the contact pressures, thereby making it possible to increase transverse grip.Furthermore, the stiffening structure contributes at least partially to bearing the load applied to the tyre, such that this applied load is taken up jointly by the tyre, by virtue of its pneumatic stiffness and its intrinsic structural stiffness, and by the stiffening structure. Thus, when the tyre is subjected to a nominal radial load, a portion of the stiffening structure arranged opposite the contact patch is placed under tension. In some embodiments, conversely, a portion of the stiffening structure arranged in line with the contact patch is subjected to compressive buckling.The presence of the stiffening structure thus makes it possible to reduce the contribution of the tyre to load bearing and therefore to reduce its structural rigidity, for example by reducing the volume of the beads. To be specific, the beads of a conventional tyre dissipate a significant amount of energy, owing to their volume and the hysteretic nature of the elastomer compound from which they are made. Reducing the volume of the beads thus makes it possible to significantly reduce rolling resistance.The tyre according to the invention has a substantially toroidal shape about an axis of revolution substantially coincident with the axis of rotation of the tyre. 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 axial direction means the direction substantially parallel to the axis of revolution of the tyre, in other words the axis of rotation of the tyre.The circumferential direction means the direction that is substantially perpendicular both to the axial direction and to a radius of the tyre (in other words, tangent to a circle centred on the axis of rotation of the tyre).The radial direction means the direction along a radius of the tyre, in other words any direction that intersects the axis of rotation of the tyre and is substantially perpendicular to that axis.The midplane of the tyre, denoted M, means the plane perpendicular to the axis of rotation of the tyre which is situated axially mid-way between the two beads and passes through the axial middle of the crown reinforcement.The circumferential equatorial plane of the tyre, denoted E, means, in a meridian section plane, the plane passing through the equator of the tyre, perpendicular to the midplane and to the radial direction. The equator of the tyre 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 tyre and situated equidistantly between the radially outermost point of the tread that is intended to be in contact with the ground, and the radially innermost point of the tyre that is intended to be in contact with a support, for example a rim.The meridian plane means a plane that is parallel to and contains the axis of rotation of the tyre and is perpendicular to the circumferential direction.Radially inner / inside and radially outer / outside mean closer to the axis of rotation of the tyre and further away from the axis of rotation of the tyre, respectively. Axially inner / inside and axially outer / outside mean closer to the midplane of the tyre and further away from the midplane of the tyre, respectively. Bead means the radial portion of the tyre intended to allow the tyre to be attached to a mounting support, for example a wheel comprising a rim. Thus, each bead is notably intended to be in contact with a flange of the rim allowing it to be attached. The bead is thus delimited radially on the inside by the radially inner end of the tyre and radially on the outside by an axial straight line passing through the radially outermost point in contact with a standard rim as defined by the 2023 European Tyre and Rim Technical Organisation (ETRTO) standard.Sidewall means the radial portion of the tyre connecting the bead to the crown. The sidewall is delimited radially on the outside by an edge of the tread. The axial edges of the tread are determined on a tyre mounted on a nominal rim and inflated to the nominal pressure as defined in the 2023 ETRTO Standards Manual. The edges are arranged on either side of the midplane of the tyre and formed by lines substantially parallel to the circumferential direction of the tyre. If there is an obvious boundary between the tread and the sidewall of the tyre, the edges are determined easily. If the tread is continuous with respect to the sidewalls, the edges are usually determined by loading the tyre to 80% of its load capacity as defined in the 2023 ETRTO Standards Manual and the edges are identified as the axial limits of the tread in contact with the ground. The sidewall is delimited radially on the inside by an axial straight line passing through the radially outermost point in contact with a standard rim as defined by the 2023 European Tyre and Rim Technical Organisation (ETRTO) standard.Any range of values denoted by the expression "between a and b" refers to the range of values ranging from more than a to less than b (i.e. excluding the limits a and b), whereas any range of values denoted by the expression "from a to b" means the range of values ranging from a to b (i.e. including the strict limits a and b).The tyres of the invention are preferably intended for passenger vehicles as defined in the 2023 European Tyre and Rim Technical Organisation (ETRTO) standard. Such a tyre has a cross section in a meridian section plane that is characterized by a section height H and a nominal section width SW as defined in the 2023 European Tyre and Rim Technical Organisation (ETRTO) standard. The values of SW and H are marked on the tyre sidewall, for example as defined in the 2023 ETRTO Standards Manual.Preferably, the passenger vehicle tyres to which the invention will advantageously be applied are such that the ratio H / S, expressed as a percentage, is at most equal to 90 and is at least equal to 20, and the nominal section width SW is at least equal to 115 mm and at most equal to 385 mm. Moreover, the diameter at the flange D, defining the diameter of the rim on which the tyre is mounted, is at least equal to 12 inches and at most equal to 30 inches.Conventionally, in a tyre comprising a crown reinforcement and a carcass reinforcement, the crown comprises a tread intended to come into contact with the rolling surface and a crown reinforcement arranged radially inside the tread. The carcass reinforcement is anchored in each bead and extends radially in each sidewall and axially in the crown radially on the inside of the crown reinforcement. Conventionally, the crown reinforcement comprises at least one crown layer comprising reinforcing elements. These reinforcing elements are preferably textile or metal filamentary elements. In embodiments that make it possible to obtain performance aspects of tyres known as radial tyres as defined by the ETRTO, the carcass reinforcement comprises at least one carcass layer, said carcass layer comprising carcass filamentary reinforcing elements, each carcass filamentary reinforcing element extending substantially in a main direction that forms an angle, as an absolute value, ranging from 80° to 90°, with the circumferential direction of the tyre. As a variant, it is possible to have a variable angle ranging from 80° to 90° in at least part of the sidewall and strictly less than 80° in at least part of the crown.In an advantageous embodiment, the stiffening structure is not impervious to a tyre inflation gas. Thus, the stiffening structure allows the inflation gas to pass through. In other words, the stiffening structure does not delimit a secondary pressurized cavity of the tyre. "Not impervious” means that the stiffening structure is permeable to the inflation gas such that the pressure is homogeneous in the toroidal cavity at all times, and notably during inflation of the tyre.Advantageously, said first radially inner anchoring point common to said first main and complementary stiffening elements and said first radially outer common anchoring point common to said first main and complementary stiffening elements are arranged on the same side of the midplane of the tyre. Advantageously, said second radially inner common anchoring point common to said second main and complementary stiffening elements and said second radially outer common anchoring point common to said second main and complementary stiffening elements are arranged on the same other side of the midplane of the tyre. Thus, the portions extending on the one hand, between a radially inner anchoring point and a radially outer anchoring point located on the same side of the midplane and on the other hand, between a radially inner anchoring point and a radially outer anchoring point located on the other side of the midplane, do not cross, which makes it possible to limit axial buckling of the tread, in other words axial compression of the tread, notably when lateral stresses are high. Thus, on the one hand, an even contact patch is maintained, and on the other hand, the risk of damage to the crown reinforcement of the tyre is reduced, in particular by preventing compression of the various constituent elements of the crown reinforcement, for example the textile and metal filamentary reinforcing elements of the crown reinforcement.In order to distribute the forces over the whole of the stiffening structure, the stiffening structure comprising a plurality of first main stiffening elements distributed circumferentially in the toroidal cavity and a plurality of first complementary stiffening elements distributed circumferentially in the toroidal cavity, the tyre comprises a plurality of first radially inner common anchoring points and a plurality of first radially outer common anchoring points, each first radially inner and outer common anchoring point of the plurality of first radially inner and radially outer common anchoring points being common to first main and complementary stiffening elements of the plurality of first main and complementary stiffening elements. Optionally, the stiffening structure comprising a plurality of second main stiffening elements distributed circumferentially in the toroidal cavity and a plurality of second complementary stiffening elements distributed circumferentially in the toroidal cavity, the tyre comprises a plurality of second radially inner common anchoring points and a plurality of second radially outer common anchoring points, each second radially inner and outer common anchoring point of the plurality of second radially inner and radially outer common anchoring points being common to second main and complementary stiffening elements of the plurality of second main and complementary stiffening elements.In preferred and optional embodiments:- said first main stiffening element comprises a portion extending continuously in the toroidal cavity from said first radially inner common anchoring point common to said first main and complementary stiffening elements to said first radially outer common anchoring point common to said first main and complementary stiffening elements, - said first complementary stiffening element comprises a portion extending continuously in the toroidal cavity from said first radially inner common anchoring point common to said first main and complementary stiffening elements to said first radially outer common anchoring point common to said first main and complementary stiffening elements.Optionally:- said second main stiffening element comprises a portion extending continuously in the toroidal cavity from said second radially inner common anchoring point common to said second main and complementary stiffening elements to said second radially outer common anchoring point common to said second main and complementary stiffening elements, - said second complementary stiffening element comprises a portion extending continuously in the toroidal cavity from said second radially inner common anchoring point common to said second main and complementary stiffening elements to said second radially outer common anchoring point common to said second main and complementary stiffening elements. Advantageously, said portion of said first main stiffening element extends continuously in the toroidal cavity in a general direction substantially parallel to the general direction in which said portion of said first complementary stiffening element extends continuously in the toroidal cavity. Optionally, said portion of said second main stiffening element extends continuously in the toroidal cavity in a general direction substantially parallel to the general direction in which said portion of said second complementary stiffening element extends continuously in the toroidal cavity. This promotes maximum take-up of forces in the direction common to the portions of the main and complementary stiffening elements.In advantageous and optional embodiments, said portion of said first main stiffening element extending continuously in the toroidal cavity has a length Lp1 and said portion of said first complementary stiffening element extending continuously in the toroidal cavity has a length Lc1, Lp1 and Lc1 satisfying 0.90 ≤ Lp1 / Lc1 ≤ 1.10. Optionally, said portion of said second main stiffening element extending continuously in the toroidal cavity has a length Lp2 and said portion of said second complementary stiffening element extending continuously in the toroidal cavity has a length Lc2, Lp2 and Lc2 satisfying 0.90 ≤ Lp2 / Lc2 ≤ 1.10. Thus, the take-up of forces is distributed over time, meaning that the tyre functions gradually and / or responsively. In the case where Lp1 and Lc1 and / or Lp2 and Lc2 are different, initially the shortest stiffening element takes up the forces owing to its relatively short length. Then, subsequently, the longer stiffening element goes taut and in turn participates in taking up the forces, which helps make the tyre function gradually. In the case where Lp1=Lc1 and / or Lp2=Lc2, the main and complementary stiffening elements take up the forces simultaneously, which helps make the tyre function highly responsively. Those skilled in the art will select the configuration best suited to the use of the tyre.Optionally and advantageously, said portion of said first main stiffening element extending continuously in the toroidal cavity is in contact with said portion of said first complementary stiffening element extending continuously in the toroidal cavity or is at a distance from said portion of said first complementary stiffening element extending continuously in the toroidal cavity, this distance being less than or equal to the largest dimension of the cross sections of said portions of said first main and complementary stiffening elements. Optionally and advantageously, said portion of said second main stiffening element extending continuously in the toroidal cavity is in contact with said portion of said second complementary stiffening element extending continuously in the toroidal cavity or is at a distance from said portion of said second complementary stiffening element extending continuously in the toroidal cavity, this distance being less than or equal to the largest dimension of the cross sections of said portions of said second main and complementary stiffening elements. "In contact” means that there is at least one point of contact between the portions of the main and complementary stiffening elements.The cross section of a portion is the section of the portion in a plane substantially perpendicular to the main direction in which the portion extends. Thus, the volumetric bulk of the stiffening structure in the toroidal cavity is minimized, which makes it easier to handle the tyre, especially during mounting and repair operations, without risking damage to the stiffening structure. In order to further reduce the volumetric bulk of the stiffening structure in the toroidal cavity, said portion of said first main stiffening element extending continuously in the toroidal cavity is in contact with said portion of said first complementary stiffening element extending continuously in the toroidal cavity over at least 50%, preferably at least 75%, of the shortest length out of the lengths of said portions of said first main and complementary stiffening elements. Optionally, said portion of said second main stiffening element extending continuously in the toroidal cavity is in contact with said portion of said second complementary stiffening element extending continuously in the toroidal cavity over at least 50%, preferably at least 75%, of the shortest length out of the lengths of said portions of said second main and complementary stiffening elements. To see the proximity or contact of the main and complementary stiffening elements, the first and second beads will be separated in order to simulate mounting of the tyre on a measuring rim as per the 2023 European Tyre and Rim Technical Organisation (ETRTO) standard.Advantageously:- said first main stiffening element comprises a radially inner anchoring portion anchored in the first sidewall and / or bead and extending in the first sidewall and / or bead from said first radially inner common anchoring point common to said first main and complementary stiffening elements, - said first complementary stiffening element comprises a radially inner anchoring portion anchored in the first sidewall and / or bead and extending in the first sidewall and / or bead from said first radially inner common anchoring point common to said first main and complementary stiffening elements. Advantageously, said portion of each first main and complementary stiffening element extending continuously in the toroidal cavity extends said radially inner anchoring portion of each first main and complementary stiffening element, respectively. Optionally:- said second main stiffening element comprises a radially inner anchoring portion anchored in the second sidewall and / or bead and extending in the second sidewall and / or bead from said second radially inner common anchoring point common to said second main and complementary stiffening elements, - said second complementary stiffening element comprises a radially inner anchoring portion anchored in the second sidewall and / or bead and extending in the second sidewall and / or bead from said second radially inner anchoring point common to said second main and complementary stiffening elements. Optionally, said portion of each second main and complementary stiffening element extending continuously in the toroidal cavity extends said radially inner anchoring portion of each second main and complementary stiffening element, respectively. According to a first design of the radially inner anchoring portions: - said radially inner anchoring portion of said first main stiffening element extends from said first radially inner common anchoring point common to said first main and complementary stiffening elements to another first radially inner anchoring point of said first main stiffening element having a first azimuth circumferentially offset with respect to an azimuth of said first radially inner common anchoring point common to said first main and complementary stiffening elements,- said radially inner anchoring portion of said first complementary stiffening element extends from said first radially inner common anchoring point common to said first main and complementary stiffening elements to another first radially inner anchoring point of said first complementary stiffening element having a second azimuth circumferentially offset with respect to the azimuth of said first radially inner common anchoring point common to said first main and complementary stiffening elements, the azimuth of said first radially inner common anchoring point common to said first main and complementary stiffening elements being arranged circumferentially between the first azimuth and the second azimuth. According to an optional variant of the first design of the radially inner anchoring portions: - said radially inner anchoring portion of said second main stiffening element extends from said second radially inner common anchoring point common to said second main and complementary stiffening elements to another second radially inner anchoring point of said second main stiffening element having a first azimuth circumferentially offset with respect to an azimuth of said second radially inner common anchoring point common to said second main and complementary stiffening elements,- said radially inner anchoring portion of said second complementary stiffening element extends from said second radially inner common anchoring point common to said second main and complementary stiffening elements to another second radially inner anchoring point of said second complementary stiffening element having a second azimuth circumferentially offset with respect to the azimuth of said second radially inner common anchoring point common to said second main and complementary stiffening elements, the azimuth of said second radially inner common anchoring point common to said second main and complementary stiffening elements being arranged circumferentially between the first azimuth and the second azimuth. According to a second design of the radially inner anchoring portions, said radially inner anchoring portion of the first main stiffening element and said radially inner anchoring portion of the first complementary stiffening element are continuous with one another in such a way as to form a loop in the first sidewall and / or bead. Optionally, in the second design of the radially inner anchoring portions, said radially inner anchoring portion of the second main stiffening element and said radially inner anchoring portion of the second complementary stiffening element are continuous with one another in such a way as to form a loop in the second sidewall and / or bead. In some advantageous embodiments:- said first main stiffening element comprises a radially outer anchoring portion anchored in the crown and extending in the crown from said first radially outer common anchoring point common to said first main and complementary stiffening elements, - said first complementary stiffening element comprises a radially outer anchoring portion anchored in the crown and extending in the crown from said first radially outer common anchoring point common to said first main and complementary stiffening elements. Advantageously, said radially outer anchoring portion of each first main and complementary stiffening element extends said portion of each first main and complementary stiffening element, respectively, extending continuously in the toroidal cavity. Optionally:- said second main stiffening element comprises a radially outer anchoring portion anchored in the crown and extending in the crown from said second radially outer common anchoring point common to said second main and complementary stiffening elements, - said second complementary stiffening element comprises a radially outer anchoring portion anchored in the crown and extending in the crown from said second radially outer common anchoring point common to said second main and complementary stiffening elements.Optionally, said radially outer anchoring portion of each second main and complementary stiffening element extends said portion of each second main and complementary stiffening element, respectively, extending continuously in the toroidal cavity. In a first configuration of the radially outer anchoring portions:- said radially outer anchoring portion of said first main stiffening element extends in the crown from said first radially outer common anchoring point common to said first main and complementary stiffening elements to another first radially outer common anchoring point common to said first main and complementary stiffening elements, - said radially outer anchoring portion of said first complementary stiffening element extends in the crown from said first radially outer common anchoring point common to said first main and complementary stiffening elements to said other first radially outer common anchoring point common to said first main and complementary stiffening elements. Advantageously, said first radially outer common anchoring point common to said first main and complementary stiffening elements is axially offset from said other first radially outer common anchoring point common to said first main and complementary stiffening elements. Preferably, said first radially outer common anchoring point common to said first main and complementary stiffening elements and said other first radially outer common anchoring point common to said first main and complementary stiffening elements are arranged on either side of the midplane of the tyre.Optionally, in this first configuration of the radially outer anchoring portions:- said radially outer anchoring portion of said second main stiffening element extends in the crown from said second radially outer common anchoring point common to said second main and complementary stiffening elements to another second radially outer common anchoring point common to said second main and complementary stiffening elements, - said radially outer anchoring portion of said second complementary stiffening element extends in the crown from said second radially outer common anchoring point common to said second main and complementary stiffening elements to said other second radially outer common anchoring point common to said second main and complementary stiffening elements. Optionally, said second radially outer common anchoring point common to said second main and complementary stiffening elements is axially offset from said other second radially outer common anchoring point common to said second main and complementary stiffening elements. Optionally, said second radially outer common anchoring point common to said second main and complementary stiffening elements and said other second radially outer common anchoring point common to said second main and complementary stiffening elements are arranged on either side of the midplane of the tyre. In a second configuration of the radially outer anchoring portions:said radially outer anchoring portion of said first main stiffening element extends in the crown from said first radially outer common anchoring point common to said first main and complementary stiffening elements to another first radially outer anchoring point of said radially outer anchoring portion of said first main stiffening element having a first azimuth,said radially outer anchoring portion of said first complementary stiffening element extends in the crown from said first radially outer common anchoring point common to said first main and complementary stiffening elements to another first radially outer anchoring point of said radially outer anchoring portion of said first complementary stiffening element having a second azimuth circumferentially offset with respect to the first azimuth. Optionally, in this second configuration of the radially outer anchoring portions:said radially outer anchoring portion of said second main stiffening element extends in the crown from said second radially outer common anchoring point common to said second main and complementary stiffening elements to another second radially outer anchoring point of said radially outer anchoring portion of said second main stiffening element having a first azimuth,said radially outer anchoring portion of said second complementary stiffening element extends in the crown from said second radially outer common anchoring point common to said second main and complementary stiffening elements to another second radially outer anchoring point of said radially outer anchoring portion of said second complementary stiffening element having a second azimuth circumferentially offset with respect to the first azimuth. In a first configuration of the main and complementary stiffening elements, each first main and complementary stiffening element respectively forms a first continuous main and complementary stiffening element which meanders at least from the first sidewall and / or bead, passing through the crown. Optionally, each second main and complementary stiffening element respectively forms a second continuous main and complementary stiffening element which meanders at least from the second sidewall and / or bead, passing through the crown. This facilitates manufacture of the tyre and improves the robustness of the stiffening structure by doing away with the ends of said stiffening element to be anchored in each sidewall and / or bead and / or in the crown. In this first configuration, it is therefore possible to have a continuous stiffening element extending over the entire circumference of the tyre. Since said stiffening element of the stiffening structure is continuous, the transmission of forces between each sidewall and / or bead is improved, the transmission of forces thus being distributed over the tyre. Thus, the stiffening structure performs its function around the entire circumference of the tyre.According to a first variant of the first configuration of the main and complementary stiffening elements, said radially outer anchoring portion of said first main stiffening element is said radially outer anchoring portion of said second main stiffening element such that said first and second main stiffening elements form a continuous main stiffening element which extends continuously from the first sidewall and / or bead to the second sidewall and / or bead, passing through the crown, in such a way as to meander from the first sidewall and / or bead to the second sidewall and / or bead. In the same first variant, said radially outer anchoring portion of said first complementary stiffening element is said radially outer anchoring portion of said second complementary stiffening element such that said first and second complementary stiffening elements form a continuous complementary stiffening element which extends continuously from the first sidewall and / or bead to the second sidewall and / or bead, passing through the crown, in such a way as to meander from the first sidewall and / or bead to the second sidewall and / or bead.According to a second variant of the first configuration of the main and complementary stiffening elements, each first main and complementary stiffening element respectively forms a continuous main and complementary stiffening element which meanders between the first sidewall and / or bead and the crown. Again in this second variant, each second main and complementary stiffening element respectively forms a continuous main and complementary stiffening element which meanders between the second sidewall and / or bead and the crown. It is also possible to envisage a tyre in which the first variant of the first configuration of the main and complementary stiffening elements is only applied to the first and second main stiffening elements and the second variant is only applied to the first and second complementary stiffening elements. In a second configuration of the main and complementary stiffening elements, the first main and complementary stiffening elements form a first continuous stiffening element which meanders at least from the first sidewall and / or bead, passing through the crown. Also preferably, the second main and complementary stiffening elements form a second continuous stiffening element which meanders at least from the second sidewall and / or bead, passing through the crown. As in the first configuration of the main and complementary stiffening elements, this facilitates manufacture of the tyre and improves the robustness of the stiffening structure by doing away with the ends of said stiffening element to be anchored in each sidewall and / or bead and / or in the crown. According to a first variant of the second configuration of the main and complementary stiffening elements, said radially outer anchoring portion of said first main stiffening element is said radially outer anchoring portion of the second main stiffening element and said radially outer anchoring portion of said first complementary stiffening element is said radially outer anchoring portion of the second complementary stiffening element, such that said first and second main and complementary stiffening elements form a continuous stiffening element which extends continuously from the first sidewall and / or bead to the second sidewall and / or bead, passing through the crown, in such a way as to meander from the first sidewall and / or bead to the second sidewall and / or bead. According to a second variant of the second configuration of the main and complementary stiffening elements, the first main and complementary stiffening elements form a first continuous stiffening element which meanders between the first sidewall and / or bead and the crown and the second main and complementary stiffening elements form a second continuous stiffening element which meanders between the second sidewall and / or bead and the crown.In a third configuration of the main and complementary stiffening elements, it may be envisaged that each first main and complementary stiffening element extend from the first sidewall and / or bead to the crown and have an end in the first sidewall and / or bead. Likewise, it may be envisaged that each second main and complementary stiffening element extend from the second sidewall and / or bead to the crown and have an end in the second sidewall and / or bead.In a first variant of this third configuration, each first main and complementary stiffening element extends from the first sidewall and / or bead to the crown, and has one end in the crown. Likewise, it may be envisaged that each second main and complementary stiffening element extend from the second sidewall and / or bead to the crown and have an end in the crown.In a second variant of this third configuration, each first main and complementary stiffening element is each second main and complementary stiffening element, respectively, and extends from the first sidewall and / or bead to the second sidewall and / or bead, passing through the crown, and has an end in each first and second sidewall and / or bead.Each stiffening element according to one of the designs or configurations defined above may be characterized geometrically, in particular by its mean section Sm, this property not necessarily being identical for all the stiffening elements. The mean section Sm is the mean of the sections obtained by sectioning the stiffening element through all of the cylindrical surfaces coaxial with the tyre and radially inside the inner toroidal cavity. In the most frequent case of a constant section, the mean section Sm is the constant section of the stiffening element. The mean section Sm comprises a largest characteristic dimension Dmax and a smallest characteristic dimension Dmin, the ratio R=Dmax / Dmin of which is referred to as the aspect ratio. By way of examples, a stiffening element having a circular mean section Sm having a diameter equal to d, has an aspect ratio R=1, a stiffening element having a rectangular mean section Sm, having a length L and a width l, has an aspect ratio R=L / l, and a stiffening element having an elliptical mean section Sm, having a major axis D and a minor axis d, has an aspect ratio R=D / d.A first type of preferred stiffening element, with an aspect ratio R at most equal to 3, is said to be one-dimensional. In other words, a stiffening element is considered to be one-dimensional when the largest characteristic dimension Dmax of its mean section Sm is at most equal to 3 times the smallest characteristic dimension Dmin of its mean section Sm. A one-dimensional stiffening element exhibits filamentary mechanical behaviour, that is, it can only be subjected to tensile or compression forces along its mean line. This is why a one-dimensional stiffening element is usually referred to as a filamentary stiffening element. Among the components commonly used in the field of tyres, textile filamentary elements, made up of an assembly of textile elementary monofilaments, or metal cords, made up of an assembly of metal elementary monofilaments, can be considered to be one-dimensional stiffening elements, as their mean section Sm is substantially circular and so the aspect ratio R is equal to 1, therefore less than 3. A second type of stiffening element, with an aspect ratio R at least equal to 3, is said to be two-dimensional. In other words, a stiffening element is considered to be two-dimensional when the largest characteristic dimension Dmax of its mean section Sm is at least equal to 3 times the smallest characteristic dimension Dmin of its mean section Sm. A two-dimensional stiffening element exhibits membranous mechanical behaviour, that is, it can only be subjected to tensile or compression forces through its thickness defined by the smallest characteristic dimension Dmin of its mean section Sm. According to a first variant, a stiffening element with an aspect ratio R at least equal to 3 and at most equal to 50 is said to be a strap-type two-dimensional stiffening element. According to a second variant, a stiffening element with an aspect ratio R at least equal to 50 is said to be a film-type two-dimensional stiffening element.The materials that can be used for each stiffening element are as described in WO2022 / 200717. In one very advantageous embodiment, the or each first and / or second main and complementary stiffening element is respectively a first and / or second filamentary main and complementary stiffening element, preferably a first and / or second textile filamentary main and complementary stiffening element. Preferably, the filamentary stiffening elements are identical, in other words they have identical geometric characteristics and constituent materials.These filamentary stiffening elements are usually referred to as stays. The benefit of using filamentary stiffening elements is that they provide a low-mass, low-hysteresis stiffening structure. Using identical filamentary stiffening elements makes it possible to obtain uniform distribution of the forces between the stiffening elements."Textile" means that each filamentary stiffening element is non-metallic, for example made from a material selected from a polyester, a polyamide, a polyketone, a polyvinyl alcohol, a cellulose, a mineral fibre, a natural fibre, an elastomer material, or a mixture of these materials. Among polyesters, mention may be made, for example, of PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PBT (polybutylene terephthalate), PBN (polybutylene naphthalate), PPT (polypropylene terephthalate) or PPN (polypropylene naphthalate). Among polyamides, mention may be made of aliphatic polyamides such as polyamides 4-6, 6, 6-6 (nylon), 11 or 12 and of aromatic polyamides such as aramid. Preferably, the material is a polyester or an aliphatic polyamide.Advantageously, at least a portion of each main and / or complementary stiffening element is coated with at least one polymer layer, preferably with at least one adhesive layer. Such a layer of polymer composition makes it possible to limit the propagation of air and potential corrosive agents along the stiffening element and therefore into the structure of the tyre. The composition is referred to as a polymer composition because it is based on a polymer composition, this polymer composition possibly comprising one or more polymers, for example selected from thermoplastic polymers, thermosetting and / or crosslinkable polymers, elastomers, thermoplastic elastomers, and also fillers and other components usually used in the field of compositions for tyres.Preferably, the adhesive composition comprises a resin selected from phenol-aldehyde resins, polyepoxide resins, polyisocyanate resins, aromatic polyepoxy-phenolic resins and polyfunctional resins, as well as mixtures of these resins. In addition to limiting the propagation of air and potential corrosive agents, the adhesive composition makes it possible to improve the anchoring of the stiffening elements in the structure of the tyre.In some embodiments, said portion of the or each first main and / or complementary stiffening element and / or of the or each second main and / or complementary stiffening element extending continuously in the toroidal cavity may be coated at least partially with the polymer composition, preferably with the adhesive composition as described above. In this instance, the polymer composition makes it possible to limit the propagation of air and potential corrosive agents.In some embodiments, said radially inner anchoring portion of the or each first main and / or complementary stiffening element and / or of the or each second main and / or complementary stiffening element may be coated at least partially with the polymer composition, preferably with the adhesive composition as described above. In this instance, the polymer composition makes it possible to improve the anchoring of the stiffening structure in the first sidewall and / or bead and / or second sidewall and / or bead.In some embodiments, said radially outer anchoring portion of the or each first main and / or complementary stiffening element and / or of the or each second main and / or complementary stiffening element may be coated at least partially with the polymer composition, preferably with the adhesive composition as described above. In this instance, the polymer composition makes it possible to improve the anchoring of the stiffening elements in the crown.Advantageously, in a variant that makes it possible to manufacture the tyre using a relatively simple method, each filamentary stiffening element extends in the toroidal cavity in a main direction that forms an angle, as an absolute value, ranging from 85° to 90°, with the circumferential direction of the tyre. In another variant that makes it possible to manufacture the tyre using a method that is more complex but makes it possible to increase the circumferential stiffness, each filamentary stiffening element extends in the toroidal cavity in a main direction that forms an angle, as an absolute value, ranging from 45° to 85°, with the circumferential direction of the tyre, as explained in particular in WO2020 / 128225.Advantageously, in embodiments that promote the durability of the stiffening structure, the tyre comprises a first inner layer carrying at least a part of the inner surface comprising a first elastomer composition in contact with said first main and complementary stiffening elements at least at the first radially inner common anchoring point and / or at the first radially outer common anchoring point.Optionally, the tyre comprises a second inner layer carrying at least partially the inner surface comprising a second elastomer composition in contact with said second main and complementary stiffening elements at least at the second radially inner common anchoring point and / or at the second radially outer common anchoring point.Preferably, said first and / or second elastomer composition comprises less than 50 phr of butyl rubber, preferably less than 10 phr of butyl rubber and is more preferably substantially without butyl rubber.Preferably, said first and / or second elastomer composition comprises at least 50 phr of a diene elastomer.The inner layer prevents the anchoring of said stiffening element from being weakened at said radially inner and / or outer anchoring point. This is because butyl rubber has relatively low adhesion with the stiffening element, which creates, in the tyre, a singular zone conducive to the initiation of cracks at the point of anchoring in the sidewall and / or bead and the crown. By adding an inner layer with a low butyl rubber content, the singular zone is eliminated, thus doing away with any risk of cracking.The term "parts per hundred rubber" or "phr" means the part by weight of a constituent per 100 parts by weight of the elastomer(s), in other words of the total weight of the elastomer(s). Thus, a constituent at 60 phr will mean, for example, 60 g of this constituent per 100 g of elastomer. As is customary, in the present patent application, the terms "elastomer" and "rubber", which are interchangeable, are used equivalently in the text."Butyl rubber” means an isobutylene homopolymer or an isobutylene-isoprene copolymer, as well as the halogenated, in particular generally brominated or chlorinated, derivatives of these isobutylene homopolymers and isobutylene-isoprene copolymers. Particularly preferably, the butyl rubber(s) which can be used in the composition are chosen from isobutylene rubbers, isobutylene-isoprene copolymers (IIR), bromobutyl rubbers such as bromoisobutylene-isoprene copolymer (BIIR) and chlorobutyl rubbers such as chloroisobutylene-isoprene copolymer (CIIR). By extension of the preceding definition, the name "butyl rubber" will also include copolymers of isobutylene and of styrene derivatives, such as brominated isobutylene / methylstyrene copolymers (BIMSs), among which is included in particular the elastomer known as Exxpro sold by the company Exxon. As examples of elastomers other than butyl rubber, mention may be made especially of diene elastomers other than the butyl elastomers mentioned above. The term diene elastomer or rubber should be understood as meaning, in a known manner, one or more elastomers derived at least in part (i.e. a homopolymer or a copolymer) from diene monomers (monomers bearing two conjugated or non-conjugated carbon-carbon double bonds). Such diene elastomers are known to those skilled in the art and, for example, described in WO2016 / 001226A1.In particularly preferred embodiments, said first and / or second elastomer composition has a modulus at 10% extension of less than or equal to 8 MPa, preferably less than or equal to 5 MPa. Such rigidity is relatively low and makes it possible to absorb the considerable deformation experienced by each stiffening element at the anchoring point in question. This improves the durability of the stiffening structure.The modulus at 10% extension of the elastomer composition is the elastic modulus of the elastomer composition measured during uniaxial tensile testing, at an elongation value of 0.1 (i.e. 10% elongation, expressed as a percentage). Uniaxial tension is applied to the test specimen at a constant rate, and the elongation and the force are measured. The measurements are taken using an INSTRON type tensile tester, at a temperature of 23°C, and a relative humidity of 50% (ISO 23529 standard). The conditions for measuring and for using the results in order to determine elongation and stress are as described in the standard NF ISO 37: 2012-03. The stress is determined for an elongation of 0.1 and the modulus of elasticity under tension at 10% elongation is calculated by determining the ratio of this stress value to the elongation value. Those skilled in the art will know how to choose and adapt the dimensions of the test specimen according to the quantity of elastomer composition accessible and available in particular in the case of test specimens taken from the tyre.Each elastomer composition is referred to as elastomer because it is based on an elastomer composition; this elastomer composition may comprise one or more elastomers, but also fillers and other components usually used in the field of tyre compounds.Preferably, the stiffening structure or said first stiffening element extending from the first sidewall and / or bead to the crown or said radially inner anchoring portion of said first stiffening element is anchored in the first sidewall and / or bead, being anchored in or around a first radially inner reinforcing structure of the stiffening structure arranged in the first sidewall and / or bead. Also preferably, the stiffening structure or said first stiffening element extending from the first sidewall and / or bead to the crown or said radially outer anchoring portion of said first stiffening element is anchored in the crown, being anchored in or around one or more radially outer reinforcing structures of the stiffening structure arranged in the crown.As a variant, the stiffening structure or said first stiffening element extending from the first sidewall and / or bead to the crown or said radially inner anchoring portion of the first stiffening element is anchored in the first sidewall and / or bead, being anchored in an elastomer mass of the first sidewall and / or bead. Also as a variant, the stiffening structure or said first stiffening element extending from the first sidewall and / or bead to the crown or said radially outer anchoring portion of the first stiffening element is anchored in the crown, being anchored in an elastomer mass of the crown.Optionally, the stiffening structure or said second stiffening element extending from the second sidewall and / or bead to the crown or said radially inner anchoring portion of the second stiffening element is anchored in the second sidewall and / or bead, being anchored in or around a second radially inner reinforcing structure of the stiffening structure arranged in the second sidewall and / or bead. Also optionally, the stiffening structure or said second stiffening element extending from the second sidewall and / or bead to the crown or said radially outer anchoring portion of the second stiffening element is anchored in the crown, being anchored in or around one or more radially outer reinforcing structures of the stiffening structure arranged in the crown.As a variant, the stiffening structure or said second stiffening element extending from the second sidewall and / or bead to the crown or said radially inner anchoring portion of the second stiffening element is anchored in the second sidewall and / or bead, being anchored in an elastomer mass of the second sidewall and / or bead. Also as a variant, the stiffening structure or said second stiffening element extending from the second sidewall and / or bead to the crown or said radially outer anchoring portion of said second stiffening element is anchored in the crown, being anchored in an elastomer mass of the crown.Of course, the tyre may comprise both the first and second radially inner reinforcing structures and the radially outer reinforcing structure or structures, or only the first and second radially inner reinforcing structures, or only the radially outer reinforcing structure or structures.Each radially inner or outer reinforcing structure is respectively arranged in the corresponding sidewall and / or bead or in the crown, that is, arranged radially inside the inner surface and embedded in the mass of material forming the corresponding sidewall and / or bead or the crown. The stiffening structure passes through the inner surface in order to be anchored in or around the corresponding radially inner reinforcing structure and / or through the inner surface in order to be anchored in or around the or one of the radially outer reinforcing structure or structures. As stated above, the stiffening structure may be anchored in or around at least one radially inner and / or outer reinforcing structure. Thus, in a first variant, the stiffening structure may be anchored in the very structure of said reinforcing structure, in other words the stiffening structure at least partially penetrates said reinforcing structure, or passes completely through it such that said reinforcing structure forms a mechanical anchor for the stiffening structure. In particular, if said reinforcing structure is an assembly of a plurality of filamentary elements, the stiffening structure is "anchored in the structure" means, for example, that the stiffening structure is wound around certain filamentary elements of said reinforcing structure so as to pass through it. In a second variant, the stiffening structure may be anchored around the very structure of said reinforcing structure, in other words the stiffening structure bears on said reinforcing structure such that said reinforcing structure takes up some of the forces exerted on the stiffening structure and anchors the stiffening structure in the sidewall and / or bead or the crown. In particular, if said reinforcing structure is an assembly of a plurality of filamentary elements, the stiffening structure is "anchored around the structure" means, for example, that the stiffening structure is wound around peripheral filamentary elements of said reinforcing structure without passing through it.In the embodiments comprising a first radially inner reinforcing structure arranged in the first sidewall and / or bead, this structure preferably comprises at least one first radially inner circumferential reinforcing element making it possible to anchor the stiffening structure. In the embodiments comprising a second radially inner reinforcing structure arranged in the second sidewall and / or bead, this structure preferably comprises at least one second radially inner circumferential reinforcing element making it possible to anchor the stiffening structure.In a preferred variant, each first and second bead respectively comprises a first and second radially inner circumferential reinforcing element suitable for making it possible to attach the tyre to a mounting support for the tyre, said first radially inner circumferential reinforcing element or each first and second radially inner circumferential reinforcing element being arranged radially outside each first and second circumferential reinforcing element suitable for making it possible to attach the tyre to a mounting support for the tyre. This reduces the propagation of the noise generated by the stiffening structure from the stiffening structure to the vehicle through the mounting support for the tyre. To be specific, the noise generated by the stiffening structure is absorbed by the structure of the tyre separating the radially inner circumferential reinforcing element in question from the radially inner circumferential reinforcing element suitable for making it possible to attach the tyre to a mounting support for the tyre situated on the same side of the midplane of the tyre. This absorption is the result of the radially inner circumferential reinforcing element in question being mechanically decoupled from said radially inner circumferential reinforcing element suitable for making it possible to attach the tyre to a mounting support for the tyre situated on the same side of the midplane of the tyre. Alternatively, said first radially inner circumferential reinforcing element or each first and second radially inner circumferential reinforcing element is suitable for making it possible to attach the tyre to a mounting support for the tyre.In one embodiment, said first radially inner circumferential reinforcing element or each first and second radially inner circumferential reinforcing element is a filamentary reinforcing element extending in a main direction forming an angle of less than or equal to 10°, preferably less than or equal to 5°, and more preferably substantially zero, with the circumferential direction of the tyre.In the embodiments comprising at least one radially outer reinforcing structure arranged in the crown, this structure preferably comprises at least one radially outer circumferential reinforcing element. In one embodiment, said radially outer circumferential reinforcing element of the or each radially outer reinforcing structure is a filamentary reinforcing element extending in a main direction forming an angle of less than or equal to 10°, preferably less than or equal to 5°, and more preferably substantially zero, with the circumferential direction of the tyre. In some embodiments, the tyre comprises first and second radially outer reinforcing structures. In these embodiments, each first and second radially outer reinforcing structure preferably respectively comprises a first and second radially outer circumferential reinforcing element, the first radially outer circumferential reinforcing element being arranged axially at a distance from said second radially outer circumferential reinforcing element. This makes it possible to reduce the reinforcing structure mass making it possible to anchor the stiffening structure in the crown and to limit over-wrapping of the crown, thus making it possible to maintain an even contact patch. Preferably, the first radially outer circumferential reinforcing element and the second radially outer circumferential reinforcing element are arranged on either side of the midplane of the tyre. This improves the axial distribution of the forces exerted by the stiffening structure on the crown. Each radially inner circumferential reinforcing element and each radially outer circumferential reinforcing element may be wound in different ways, as described in particular in WO2022 / 200717. Of course, the tyre may comprise a plurality of said first and / or second radially inner and / or outer reinforcing structures. In particular embodiments, the stiffening structure extending in the toroidal cavity from at least the first sidewall and / or bead to at least the crown and being anchored in or around the first radially inner reinforcing structure, said first reinforcing structure comprising a first radially inner circumferential reinforcing element, the stiffening structure is anchored around said first radially inner circumferential reinforcing element such that a first circumferential overlap ratio between the stiffening structure and said first radially inner circumferential reinforcing element is at least equal to 5%, preferably 10%, more preferably 15% and even more preferably 20%.In particular embodiments, the stiffening structure extending in the toroidal cavity from at least the second sidewall and / or bead to at least the crown and being anchored in or around the second radially inner reinforcing structure, said second reinforcing structure comprising a second radially inner circumferential reinforcing element, the stiffening structure is anchored around said second radially inner circumferential reinforcing element such that a second circumferential overlap ratio between the stiffening structure and said second radially inner circumferential reinforcing element is at least equal to 5%, preferably 10%, more preferably 15% and even more preferably 20%. Each circumferential overlap ratio is defined as the total circumferential overlap length between the stiffening structure and said radially inner circumferential reinforcing element of the radially inner reinforcing structure in question divided by the circumference of said radially inner circumferential reinforcing element.The total circumferential overlap length between the stiffening structure and the radially inner circumferential reinforcing element in question is the length, in the circumferential direction, over which there is an overlap between the stiffening structure and the radially inner circumferential reinforcing element in question. An overlap does not necessarily mean that the stiffening structure is in contact with the radially inner circumferential reinforcing element in question, but that there is superposition between the stiffening structure and the radially inner circumferential reinforcing element in question, allowing a force to be taken up by the radially inner circumferential reinforcing element in question.The circumference of the radially inner circumferential reinforcing element in question is measured or determined as the length travelled by the centre of gravity of the section of the radially inner circumferential reinforcing element in question to make one turn of the tyre.In some embodiments, the radially inner reinforcing structure comprises a plurality of radially inner circumferential reinforcing elements. In these embodiments, part of the stiffening structure is anchored in or around one of the radially inner circumferential reinforcing elements and another part of the stiffening structure is anchored in or around another of the radially inner circumferential reinforcing elements. The circumferential overlap ratio is then the sum of the circumferential overlap ratios between each part of the stiffening structure and each corresponding radially inner circumferential reinforcing element.By virtue of the invention, it is thus possible to achieve one or more relatively high circumferential overlap ratios and thus obtain a good compromise between, on the one hand, a number of stiffening elements which is sufficiently high to reduce local stresses and, on the other hand, a reduced number of radially inner and outer common anchoring points so as not to complicate the structure of the tyre and to manufacture the tyre simply, in particular by means of a moulding device as described in WO2022 / 200718. To be specific, care will be taken to ensure that only a moderate number of stiffening elements pass through the tyre moulding device so as not to excessively weaken this moulding device.For mild-wear scenarios, one or more overlap ratios of at least 5% will be preferred. For use in sports vehicles, one or more overlap ratios of at least 10% will be preferred. For use on a race track, one or more overlap ratios of at least 15% will be preferred. It is even possible to envisage at least one of said first and second circumferential overlap ratios, preferably each first and second circumferential overlap ratio, at least equal to 20%, preferably at least equal to 25%, more preferably at least equal to 35%.Advantageously, the first circumferential overlap ratio or at least one of said first and second circumferential overlap ratios is at most equal to 50%, preferably at most equal to 45%. Advantageously, each first and second circumferential overlap ratio is at most equal to 50%, preferably at most equal to 45%. Too high a circumferential overlap ratio makes the tyre structure too complex and its manufacture too expensive.Of course, different first and second ratios may be envisaged.Brief description of the drawingsThe present invention will be understood better from studying the detailed description of embodiments that are given by way of entirely non-limiting examples and are illustrated by the appended drawings, in which:- Figure 1 is a view of a tyre, in a meridian section plane parallel to the axis of rotation, according to a first example of an embodiment of the invention; - Figures 2 and 3 each schematically show the arrangement of the stiffening structure in each first and second bead of the tyre in Figure 1;- Figure 4 schematically shows the arrangement of the stiffening structure in the toroidal cavity of the tyre in Figure 1;- Figure 5 schematically shows the arrangement of the stiffening structure in the crown of the tyre in Figure 1;- Figures 6 and 7 each schematically show the arrangement of the first main and complementary stiffening elements of the stiffening structure in the first bead of the tyre in Figure 1; - Figures 8 to 12 are schematic views similar to those in Figures 1 to 5, respectively, of a tyre according to a second example of an embodiment of the invention; and- Figures 13 and 14 are each a schematic view similar to those in Figures 1 and 8, respectively, of tyres according to the third and fourth examples of an embodiment of the invention. Detailed description A frame of reference X, Y, Z corresponding respectively to the usual axial (Y), radial (Z) and circumferential (X) directions of a tyre is shown in the figures relating to the tyre.The figures show a tyre 10 having a substantially toroidal shape about an axis of revolution substantially parallel to the axial direction Y. The tyre 10 is intended for a passenger vehicle and is a size 275 / 35ZR19. In the various figures, the tyre 10 is shown as new, i.e. when it has not yet been run. The tyre 10 comprises a crown 12 comprising a tread 14 intended to come into contact with the ground when it is running and a crown reinforcement 16 extending in the crown 12 in the circumferential direction X. The tyre 10 also comprises an inner layer 18.The tyre 10 further comprises a crown reinforcement identical to the one described in WO2022 / 200717 comprising a working reinforcement 20 comprising working layers 24, 26, and a hoop reinforcement 22 comprising a hooping layer 28.The tyre 10 comprises first and second sidewalls 30A, 30B continuing the crown 12 radially towards the inside. The second sidewall 30B is opposite the first sidewall 30A with respect to the midplane M. The tyre 10 further comprises first and second beads 32A, 32B that respectively extend each first and second sidewall 30A, 30B radially inwards. The second bead 32B is opposite the first bead 32A with respect to the midplane M. Each first and second sidewall 30A, 30B respectively connects each first and second bead 32A, 32B to the crown 12. An inner surface 34, intended to be in contact with the inflation gas of the tyre, delimits a toroidal inflation cavity 36 of the tyre 10. The inner surface 34 is in this instance supported at least partially by the inner layer 18. The inner layer 18 comprises an elastomer composition having a modulus at 10% extension of less than or equal to 8 MPa, preferably less than or equal to 5 MPa, and in this instance equal to 3 MPa. Moreover, the elastomer composition comprises less than 50 phr of butyl rubber, preferably less than 10 phr of butyl rubber and is more preferably in this instance substantially without butyl rubber. Furthermore, the elastomer composition comprises at least 50 phr of a diene elastomer, for example natural rubber. Those skilled in the art will have no difficulty formulating and manufacturing such a composition.The tyre 10 comprises first and second radially inner reinforcing structures 38A, 38B respectively arranged in each first and second bead 32A, 32B. Each first and second radially inner reinforcing structure 38A, 38B respectively comprises first and second radially inner circumferential reinforcing elements 40A, 40B, respectively arranged in each first and second bead 32A, 32B, in this instance comprising first and second filamentary reinforcing elements as described in WO2022 / 200717. Each first and second bead 32A, 32B respectively comprises a first and second radially inner circumferential reinforcing element 42A, 42B, in this instance a bead wire, suitable for making it possible to attach the tyre 10 to a mounting support for the tyre 10, for example a rim.Each first and second radially inner circumferential reinforcing element 40A, 40B is respectively arranged radially outside each first and second radially inner circumferential reinforcing element 42A, 42B suitable for making it possible to attach the tyre 10 to a mounting support for the tyre 10. The tyre 10 further comprises first and second radially outer reinforcing structures 44A, 44B arranged in the crown 12 and each provided respectively with a first and second radially outer circumferential reinforcing element 46A, 46B arranged axially on either side of the midplane M of the tyre 10 and in this instance substantially symmetrically about the midplane M of the tyre 10. Each first and second radially outer circumferential reinforcing element 46A, 46B is as described in WO2022 / 200717. The tyre 10 comprises a carcass reinforcement 48 anchored in each first and second bead 32A, 32B, in this case wound around each first and second radially inner circumferential reinforcing element 42A, 42B suitable for making it possible to attach the tyre 10 to a mounting support for the tyre 10. The carcass reinforcement 48 extends in each first and second bead 32A, 32B and in each first and second sidewall 30A, 30B such that each first and second radially inner circumferential reinforcing element 40A, 40B is arranged radially inside the carcass reinforcement 48. The carcass reinforcement 48 also extends in the crown 12, radially inside the crown reinforcement 16. The crown reinforcement 16 is arranged radially between the tread 14 and the carcass reinforcement 48. The carcass reinforcement 48 comprises at least one carcass layer 50 and in this instance comprises a single carcass layer 50. The various crown layers 24, 26, 28 and carcass layer 50 are identical to those described in WO2022 / 200717.With reference to Figures 1 to 7, the tyre 10 comprises a stiffening structure 52 that extends in the toroidal cavity 36 from the first bead 32A to the crown 12 and is anchored in the first bead 32A, being anchored around the first radially inner reinforcing structure 38A. The stiffening structure 52 extends in the toroidal cavity 36 from the second bead 32B to the crown 12 and is anchored in the second bead 32B, being anchored around the second radially inner reinforcing structure 38B. The stiffening structure 52 extends in the toroidal cavity 36 from the first bead 32A and from the second bead 32B to the crown 12 and is anchored in the crown 12, being anchored around the radially outer reinforcing structures 44A, 44B.The stiffening structure 52 comprises a plurality of stiffening elements 54 distributed circumferentially in the toroidal cavity 36 comprising first main stiffening elements 54C and first complementary stiffening elements 54D extending continuously in the toroidal cavity 36. The first main stiffening elements 54C are distinct from the first complementary stiffening elements 54D.The plurality of stiffening elements 54 also comprises second main stiffening elements 54E and second complementary stiffening elements 54F extending continuously in the toroidal cavity 36. The second main stiffening elements 54E are distinct from the second complementary stiffening elements 54F. Each stiffening element 54 is a textile filamentary stiffening element comprising an assembly of three multifilament plies of aliphatic polyamide, for example nylon, these three multifilament plies being twisted in a helix individually at 190 turns per metre in one direction and then twisted together in a helix at 190 turns per metre in the opposite direction. Each of these multifilament plies has a thread count equal to 188 tex and has a diameter D in this instance equal to 0.97 mm. Each stiffening element 54 is fully coated with an adhesive composition, in this instance an adhesive composition comprising a phenol-aldehyde resin based on resorcinol, formaldehyde and an elastomer latex as described in WO2013017422. As a variant, any other adhesive described in WO2013017422 may be used.Each first main and complementary stiffening element 54C, 54D extends continuously from the first sidewall 30A and / or the first bead 32A to the crown 12 and in this instance from the first bead 32A to the crown 12. Each second main and complementary stiffening element 54E, 54F extends continuously from the second sidewall 30A and / or the second bead 32A to the crown 12 and in this instance from the second bead 32A to the crown 12.In order to ensure optimum anchoring of each stiffening element 54, each first and second radially inner reinforcing structure 38A, 38B, in particular each first and second radially inner circumferential reinforcing element 40A, 40B, has relatively high extension stiffness and bending stiffness. Furthermore, again with the aim of optimizing the anchoring of each stiffening element 54, each first and second radially inner circumferential reinforcing element 40A, 40B is covered with a coating mass 47A, 47B made of one or more materials, preferably elastomer.In order to ensure optimum anchoring of each stiffening element 54, each first and second radially outer reinforcing structure 44A, 44B, in particular each first and second radially outer circumferential reinforcing element 46A, 46B, has relatively high extension stiffness and relatively low bending stiffness in order to limit over-wrapping of the crown 12 and eliminate the risk of impairing flattening of the tread 14. Furthermore, again with the aim of optimizing the anchoring of each stiffening element 54, each first and second radially outer circumferential reinforcing element 46A, 46B is covered with a coating mass made of one or more materials, preferably elastomer.Each first main and complementary stiffening element 54C, 54D is anchored, in the first bead 32A, around the first radially inner reinforcing structure 38A, in particular around the first radially inner circumferential reinforcing element 40A. Each second main and complementary stiffening element 54E, 54F is anchored, in the second bead 32B, around the second radially inner reinforcing structure 38B, in particular around the second radially inner circumferential reinforcing element 40B. In this instance, each first and second main and complementary stiffening element 54C, 54D and 54E, 54F is wound at least partially respectively around each first and second radially inner circumferential reinforcing element 40A, 40B. Each first and second main and complementary stiffening element 54C, 54D and 54E, 54F is also anchored, in the crown 12, respectively around each first and second radially outer reinforcing structure 44A, 44B, in particular around each first and second radially outer circumferential reinforcing element 46A, 46B. In this instance, each first and second main and complementary stiffening element 54C, 54D and 54E, 54F is wound at least partially respectively around each first and second radially outer circumferential reinforcing element 46A, 46B. The tyre 10 comprises first radially inner anchoring points 56A and radially outer anchoring points 58C common to the first main and complementary stiffening elements 54C, 54D and second radially inner anchoring points 56E and radially outer anchoring points 58E common to the second main and complementary stiffening elements 54E, 54F.Each first main and complementary stiffening element 54C, 54D passes through the inner surface 34 at the first radially inner common anchoring point 56C in the first bead 32A so as to be anchored around the first radially inner reinforcing structure 38A and at the first radially outer common anchoring point 58C in the crown 12 so as to be anchored around the first radially outer reinforcing structure 44A. Each second main and complementary stiffening element 54E, 54F passes through the inner surface 34 at the second radially inner common anchoring point 56E in the second bead 32B so as to be anchored around the second radially inner reinforcing structure 38B and at the second radially outer common anchoring point 58E in the crown 12 so as to be anchored around the second radially outer reinforcing structure 44B. The elastomer composition of the inner layer 18 is in contact with the first main and complementary stiffening elements 54C, 54D at each first radially inner common anchoring point 56C and radially outer common anchoring point 58C. The elastomer composition of the inner layer 18 is also in contact with the second main and complementary stiffening elements 54E, 54F at each second radially inner common anchoring point 56E and radially outer common anchoring point 58E. As shown in Figures 1 to 3, each first main stiffening element 54C comprises a radially inner anchoring portion 541C anchored around the first radially inner reinforcing structure 38A and extending in the first bead 32A from the first radially inner common anchoring point 56C to another first radially inner anchoring point 56C’ of the first main stiffening element 54C having a first azimuth AZ1 circumferentially offset with respect to an azimuth AZ of the first radially inner common anchoring point 56C. Likewise, each second main stiffening element 54E comprises a radially inner anchoring portion 542E anchored around the second radially inner reinforcing structure 38B and extending in the second bead 32B from the second radially inner common anchoring point 56E to another second radially inner anchoring point 56E’ of the second main stiffening element 54E having a second azimuth AZ1 circumferentially offset with respect to an azimuth AZ of the second radially inner common anchoring point 56E. Again with reference to Figures 1 to 3, each first complementary stiffening element 54D comprises a radially inner anchoring portion 541D anchored around the first radially inner reinforcing structure 38A and extending in the first bead 32A from the first radially inner common anchoring point 56C to another first radially inner anchoring point 56C’’ of the first complementary stiffening element 54D having a second azimuth AZ2 circumferentially offset with respect to the azimuth AZ of the first radially inner common anchoring point 56C. The azimuth AZ of the first radially inner common anchoring point 56C is arranged circumferentially between the first azimuth AZ1 and the second azimuth AZ2. Likewise, each second complementary stiffening element 54F comprises a radially inner anchoring portion 542F anchored in the second radially inner reinforcing structure 38B and extending in the second bead 32B from the second radially inner common anchoring point 56E to another second radially inner anchoring point 56E’’ of the second complementary stiffening element 54F having a second azimuth AZ2’ circumferentially offset with respect to the azimuth AZ’ of the second radially inner common anchoring point 56E, and the azimuth AZ’ of the second radially inner common anchoring point 56E is arranged circumferentially between the first azimuth AZ1’ and the second azimuth AZ2’.As shown in Figures 2 and 3 and in Figures 6 and 7, each first and second main stiffening element 54C, 54E is anchored around each first and second radially inner circumferential reinforcing element 40A, 40B in contact with a decoupling mass 49A, 49B interposed between each first and second main stiffening element 54C, 54E and respectively each first and second complementary stiffening element 54D, 54F. Each first and second complementary stiffening element 54D, 54F is anchored around each first and second radially inner circumferential reinforcing element 40A, 40B in contact with the coating mass 47A, 47B.With reference to Figures 1 and 4, each first main and complementary stiffening element 54C, 54D respectively comprises a portion 543C, 543D extending continuously in the toroidal cavity 36 from the first radially inner common anchoring point 56C to the first radially outer common anchoring point 58C. The portion 543C extends in the toroidal cavity 36 in a general direction substantially parallel to the general direction in which the portion 543D extends continuously. Likewise, each second main and complementary stiffening element 54E, 54D respectively comprises a portion 544E, 544F extending continuously in the toroidal cavity 36 from the second radially inner common anchoring point 56E to the second radially outer common anchoring point 58E. The portion 544E extends in the toroidal cavity 36 in a general direction substantially parallel to the general direction in which the portion 544F extends continuously.Each portion 543C, 543D respectively has a length Lp1, Lc1 satisfying 0.90 ≤ Lp1 / Lc1 ≤ 1.10 and in this instance Lp1 / Lc1=1.01. Likewise, each portion 544E, 544F respectively has a length Lp2, Lc2 satisfying 0.90 ≤ Lp2 / Lc2 ≤ 1.10 and in this instance Lp2 / Lc2=1.01. The portion 543C is in contact with the portion 543D over at least 50%, preferably at least 75%, and in this instance over 100% of the length Lc1 of the portion 543D. The portion 544E is in contact with the portion 544F over at least 50%, preferably at least 75%, and in this instance over 100% of the length Lc2 of the portion 544F.With reference to Figures 1 and 5, each first main and complementary stiffening element 54C, 54D comprises a radially outer anchoring portion 545C, 545D anchored in the crown 12 and extending in the crown 12 from the first radially outer common anchoring point 58C to another first radially outer common anchoring point 58E, common to the first main and complementary stiffening elements 54C, 54D. Likewise, each second main and complementary stiffening element 54E, 54F comprises a radially outer anchoring portion 545E, 545F anchored in the crown 12 and extending in the crown 12 from the second radially outer common anchoring point 58E to another second radially outer anchoring point 58C common to the second main and complementary stiffening elements 54E, 54F. Each portion 543C, 543D, 544E, 544F extending continuously in the toroidal cavity 36 respectively extends each radially inner anchoring portion 541C, 541D, 542E, 542F. Each radially outer anchoring portion 545C, 545D, 545E, 545F respectively extends each portion 543C, 543D, 544E, 544F extending continuously in the toroidal cavity 36. The first and second radially outer common anchoring points 58C, 58E are axially offset from one another. The first and second radially outer common anchoring points 58C, 58E are arranged on either side of the midplane M. The first radially inner common anchoring point 56C and radially outer common anchoring point 58C are arranged on the same side of the midplane M. The second radially inner common anchoring point 56E and radially outer common anchoring point 58E are arranged on the same side of the midplane M. Thus, the stiffening structure 52 in this instance comprises 240 first and second continuous main stiffening elements 54C, 54E and 240 first and second complementary stiffening elements 54D, 54F, making a total of 480 continuous main and complementary stiffening elements. A stiffening element is counted each time a separate portion of a stiffening element extends in the toroidal cavity 36 from a sidewall and / or bead to the crown.The stiffening structure 52, in particular the plurality of first main and complementary stiffening elements 54C, 54D, in particular the radially inner anchoring portions 541C, 541D, is anchored and are anchored around the first radially inner reinforcing structure 38A, in particular the first radially inner circumferential reinforcing element 40A, such that a first circumferential overlap ratio is at least equal to 15%, preferably at least equal to 20%, more preferably at least equal to 25% and even more preferably at least equal to 35%. Figure 6 shows the first radially inner circumferential reinforcing element 40A and the decoupling mass 49A around which each first main stiffening element 54C is anchored, disregarding each first complementary stiffening element 54D. Figure 7 shows the first radially inner circumferential reinforcing element 40A and the coating mass 47A around which each first complementary stiffening element 54D is anchored, disregarding each first main stiffening element 54C.As shown in Figures 6 and 7, the first circumferential overlap ratio is defined as the total overlap length between the stiffening structure 52 and the first radially inner circumferential reinforcing element 40A, in this instance the sum of the overlap lengths between the radially inner anchoring portions 541C, 541D of each first main and complementary stiffening element 54C, 54D and the first radially inner circumferential reinforcing element 40A, divided by the circumference of the first radially inner circumferential reinforcing element 40A. In this case, each overlap length is substantially equal to the diameter D of each first and second main and complementary stiffening element 54C, 54D described above, such that the sum of the overlap lengths of the first main stiffening elements 54C is equal to 233 mm (240 x 0.97 mm) and the sum of the overlap lengths of the first complementary stiffening elements 54D is equal to 233 mm (240 x 0.97 mm). Thus, the total overlap length of the first and second main and complementary stiffening elements 54C, 54D is equal to 466 mm. The circumference of the first radially inner circumferential reinforcing element is in this instance equal to 1723 mm.Likewise, the stiffening structure 52, in particular the plurality of second main and complementary stiffening elements 54E, 54F, in particular the radially inner anchoring portions 542E, 542F, is anchored and are anchored around the second radially inner reinforcing structure 38B, in particular the second radially inner circumferential reinforcing element 40B, such that a second circumferential overlap ratio is at least equal to 15%, preferably at least equal to 20%, more preferably at least equal to 25%. In other embodiments, it may be envisaged that the first and / or second circumferential overlap ratio be at least equal to 35%. The second circumferential overlap ratio is defined in the same way, mutatis mutandis, as the first circumferential overlap ratio. Advantageously, the first and second circumferential overlap ratios are each at most equal to 50%, more advantageously at most equal to 45%. In this case, each first and second circumferential overlap ratio is equal to 27% (466 mm / 1723 mm).As shown in Figure 1, the first radially inner common anchoring point 56C and radially outer common anchoring point 58C are arranged axially on the same side as the first radially inner reinforcing structure 38A with respect to the midplane M. The second radially inner common anchoring point 56E and radially outer common anchoring point 58E are arranged axially on the same other side as the second radially inner reinforcing structure 38B with respect to the midplane M. Each first and second radially inner common anchoring point 56C, 56E and radially outer common anchoring point 58C, 58E is arranged such that the portions 543C, 543D and the portions 544E, 544F do not intersect in the toroidal cavity 36.Each first main and complementary stiffening element 54C, 54D respectively forms a first continuous main and complementary stiffening element which meanders at least from the first bead 32A, passing through the crown 12. Each second main and complementary stiffening element 54E, 54F respectively forms a second continuous main and complementary stiffening element which meanders at least from the second bead 32B, passing through the crown 12. More specifically, each radially outer anchoring portion 545C is the radially outer anchoring portion 545E such that the first and second main stiffening elements 54C, 54E form a continuous main stiffening element which extends continuously from the first bead 32A to the second bead 32B, passing through the crown 12, in such a way as to meander from the first bead 32A to the second bead 32B. Each radially outer anchoring portion 545D is the radially outer anchoring portion 545F such that the first and second complementary stiffening elements 54D, 54F form a continuous complementary stiffening element which extends continuously from the first bead 32A to the second bead 32B, passing through the crown 12, in such a way as to meander from the first bead 32A to the second bead 32B.The second example of an embodiment shown in Figures 8 to 12, in which elements identical to those in the preceding figures bear the same reference numerals, differs from the first example shown in Figures 1 to 7 in that the radially inner anchoring portion 541C of the first main stiffening element 54C and the radially inner anchoring portion 541D of the first complementary stiffening element 54D are continuous with one another so as to form a loop 541E in the first bead 32A. Moreover, the radially inner anchoring portion 542E of the second main stiffening element 54E and the radially inner anchoring portion 542F of the second complementary stiffening element 54F are continuous with one another so as to form a loop 542G in the second bead 32B.With reference to Figures 8 and 12, the radially outer anchoring portion 545C of the first main stiffening element 54C extends in the crown 12 from the first radially outer common anchoring point 58C to another first radially outer anchoring point 58G’ of the radially outer anchoring portion 545C having a first azimuth AZPG. The radially outer anchoring portion 545D of the first complementary stiffening element 54D extends in the crown 12 from the first radially outer common anchoring point 58C to another first radially outer anchoring point 58G’’ of the radially outer anchoring portion 545D having a second azimuth AZSG circumferentially offset with respect to the first azimuth AZPG. The radially outer anchoring portion 545E of the second main stiffening element 54E extends in the crown 12 from the second radially outer common anchoring point 58E to another second radially outer anchoring point 58H’ of the radially outer anchoring portion 545E having a first azimuth AZPH. The radially outer anchoring portion 545F of the second complementary stiffening element 54F extends in the crown 12 from the second radially outer common anchoring point 58E to another second radially outer anchoring point 58H’’ of the radially outer anchoring portion 545F having a second azimuth AZSH circumferentially offset with respect to the first azimuth AZPH.The first main 54C and complementary 54D stiffening elements form a first continuous stiffening element which meanders at least from the first bead 32A, passing through the crown 12, and the second main 54E and complementary 54F stiffening elements form a second continuous stiffening element which meanders at least from the second bead 32B, passing through the crown 12. More specifically, the radially outer anchoring portion 545C is the radially outer anchoring portion 545E and the radially outer anchoring portion 545D is the radially outer anchoring portion 545F such that said first and second main and complementary stiffening elements form a continuous stiffening element which extends continuously from the first bead 32A to the second bead 32B, passing through the crown 12, in such a way as to meander from the first bead 32A to the second bead 32B. Thus, the radially outer anchoring points 58C and 58H’ coincide and the radially outer anchoring points 58E and 58G’ coincide. The third example of an embodiment shown in Figure 13, in which elements identical to those in the preceding figures bear the same reference numerals, differs from the third example in that the tyre 10 comprises a single radially outer reinforcing structure 44 comprising a single radially outer circumferential reinforcing element 46. The fourth example of an embodiment shown in Figure 14, in which elements identical to those in the preceding figures bear the same reference numerals, differs from the second example by its stiffening structure 52 in which each first main and complementary stiffening element 54C, 54D forms a first continuous stiffening element which meanders between the first bead 32A and the crown 12 without going as far as the second bead 32B (and / or sidewall 30B) and in which each second main and complementary stiffening element 54E, 54F forms a second continuous stiffening element which meanders between the second bead 32B and the crown 12 without going as far as the first bead 32A (and / or sidewall 30A).In the examples illustrated in Figures 8 to 14, the first and second circumferential overlap ratios are also equal to 27%.Comparative testsThe tyre according to the first example of the invention described above, and a control tyre as described in WO2022 / 200715 and WO2022 / 200717, were tested. These tests were carried out on a rolling machine simulating the stresses experienced on the Nürburgring race track (Germany) by the tested tyre under extreme racing stress conditions in order to cause deterioration of the stiffening structure. The control tyre comprises only the continuous main stiffening element but not the continuous complementary stiffening element. Thus, each first and second circumferential overlap ratio of the control tyre is equal to 13.5%.The control tyre travelled almost 2 laps before the radially inner anchoring portion of one of the first and second beads (the one arranged on the outside of the vehicle) failed, with more than 90% of the stiffening elements failing.The tyre according to the first example of the invention completed 10 laps without damage and then 5 additional laps after which 46% of the stiffening elements had come loose in one of the first and second beads (the one arranged on the outside of the vehicle), in 37% of the stiffening elements one of the first and second had failed, and 17% of the stiffening elements showed no damage.Thus, the invention has made it possible to significantly improve the durability of the stiffening structure.Obviously, the invention is not limited to the embodiments described above. It is thus possible to envisage a stiffening structure comprising first main and complementary stiffening elements and, in addition, a first additional stiffening element, the radially inner and outer anchoring points being common to the first main, complementary and additional stiffening elements.  

Claims

1. Tyre (10) comprising a crown (12), first and second sidewalls (30A, 30B) each extending the crown (12) radially inwards, first and second beads (32A, 32B) respectively extending the first and second sidewalls (30A, 30B) radially inwards, the tyre (10) being provided with an inner surface (34) delimiting a toroidal inflation cavity (36) of the tyre (10), the tyre (10) comprising a stiffening structure (52) comprising:- at least a first main stiffening element (54C) extending continuously in the toroidal cavity (36) from at least the first sidewall (30A) and / or bead (32A) to at least the crown (12), and being anchored in the first sidewall (30A) and / or bead (32A) and in the crown (12), - at least a first complementary stiffening element (54D), distinct from said first main stiffening element (54C), extending continuously in the toroidal cavity (36) from at least the first sidewall (30A) and / or bead (32A) to at least the crown (12), and being anchored in the first sidewall (30A) and / or bead (32A) and in the crown (12),the tyre (10) comprises a first radially inner common anchoring point (56C) common to said first main and complementary stiffening elements (54C, 54D) in the first sidewall (30A) and / or bead (32A) and a first radially outer common anchoring point (58C) common to said first main and complementary stiffening elements (54C, 54D) in the crown (12).

2. Tyre (10) according to the preceding claim, wherein the stiffening structure (52) comprises:- at least a second main stiffening element (54E) extending continuously in the toroidal cavity (36) from at least the second sidewall (30B) and / or bead (32B) to at least the crown (12), and being anchored in the second sidewall (30B) and / or bead (32B) and in the crown (12), - at least a second complementary stiffening element (54F), distinct from said second main stiffening element (54E), extending continuously in the toroidal cavity (36) from at least the second sidewall (30B) and / or bead (32B) to at least the crown (12), and being anchored in the second sidewall (30B) and / or bead (32B) and in the crown (12), the tyre (10) comprises a second radially inner common anchoring point (56E) common to said second main and complementary stiffening elements (54E, 54F) in the second sidewall (30B) and / or bead (32B) and a second radially outer common anchoring point (58E) common to said second main and complementary stiffening elements (54E, 54F) in the crown (12).

3. Tyre (10) according to any one of the preceding claims, wherein: - said first main stiffening element (54C) comprises a portion (543C) extending continuously in the toroidal cavity (36) from said first radially inner common anchoring point (56C) common to said first main and complementary stiffening elements (54C, 54D) to said first radially outer common anchoring point (58C) common to said first main and complementary stiffening elements (54C, 54D), - said first complementary stiffening element (54D) comprises a portion (543D) extending continuously in the toroidal cavity (36) from said first radially inner common anchoring point (56C) common to said first main and complementary stiffening elements (54C, 54D) to said first radially outer common anchoring point (58C) common to said first main and complementary stiffening elements (54C, 54D).

4. Tyre (10) according to the preceding claim, wherein said portion (543C) of the first main stiffening element (54C) extends continuously in the toroidal cavity (36) in a general direction substantially parallel to the general direction in which said portion (543D) of the first complementary stiffening element (54D) extends continuously in the toroidal cavity (36).

5. Tyre (10) according to any one of the preceding claims, wherein:- said first main stiffening element (54C) comprises a radially inner anchoring portion (541C) anchored in the first sidewall (30A) and / or bead (32A) and extending in the first sidewall (30A) and / or bead (32A) from the first radially inner common anchoring point (56C) common to said first main and complementary stiffening elements, - said first complementary stiffening element (54D) comprises a radially inner anchoring portion (541D) anchored in the first sidewall (30A) and / or bead (32A) and extending in the first sidewall (30A) and / or bead (32A) from the first radially inner common anchoring point (56C) common to said first main and complementary stiffening elements.

6. Tyre (10) according to Claim 5, wherein:- said radially inner anchoring portion (541C) of said first main stiffening element (54C) extends from said first radially inner common anchoring point (56C) common to said first main and complementary stiffening elements (54C, 54D) to another first radially inner anchoring point (56C’) of said first main stiffening element having a first azimuth (AZ1) circumferentially offset with respect to an azimuth (AZ) of the first radially inner common anchoring point (56C) common to said first main and complementary stiffening elements (54C, 54D), - said radially inner anchoring portion (541D) of said first complementary stiffening element extends (54D) from said first radially inner common anchoring point (56C) common to said first main and complementary stiffening elements (54C, 54D) to another first radially inner anchoring point (56C’’) of said first complementary stiffening element having a second azimuth (AZ2) circumferentially offset with respect to the azimuth (AZ) of the first radially inner common anchoring point (56C) common to said first main and complementary stiffening elements (54C, 54D), the azimuth (AZ) of the first radially inner common anchoring point (56C) common to said first main and complementary stiffening elements (54C, 54D) being arranged circumferentially between the first azimuth (AZ1) and the second azimuth (AZ2).

7. Tyre (10) according to Claim 5, wherein said radially inner anchoring portion (541C) of the first main stiffening element (54C) and said radially inner anchoring portion (541D) of the first complementary stiffening element (54D) are continuous with one another so as to form a loop (541E) in the first sidewall (30A) and / or bead (32A).

8. Tyre (10) according to any one of the preceding claims, wherein: - said first main stiffening element (54C) comprises a radially outer anchoring portion (545C) anchored in the crown and extending in the crown (12) from the first radially outer common anchoring point (58C) common to said first main and complementary stiffening elements, - said first complementary stiffening element (54D) comprises a radially outer anchoring portion (545D) anchored in the crown and extending in the crown (12) from the first radially outer common anchoring point (58C) common to said first main and complementary stiffening elements.

9. Tyre (10) according to Claim the preceding claim, wherein: - said radially outer anchoring portion (545C) of said first main stiffening element (54C) extends in the crown (12) from said first radially outer common anchoring point (58C) common to said first main and complementary stiffening elements (54C, 54D) to another first radially outer common anchoring point (58E) common to said first main and complementary stiffening elements (54C, 54D), - said radially outer anchoring portion (545D) of said first complementary stiffening element (54D) extends in the crown (12) from said first radially outer common anchoring point (58C) common to said first main and complementary stiffening elements (54C, 54D) to said other first radially outer anchoring point (58E) common to said first main and complementary stiffening elements (54C, 54D).

10. Tyre (10) according to Claim 8, wherein:- said radially outer anchoring portion (545C) of said first main stiffening element (54C) extends in the crown (12) from said first radially outer common anchoring point (58C) common to said first main and complementary stiffening elements to another first radially outer anchoring point (58G’) of said radially outer anchoring portion (545C) of said first main stiffening element having a first azimuth (AZPG),- said radially outer anchoring portion (545D) of said first complementary stiffening element (54D) extends in the crown (12) from said first radially outer common anchoring point (58C) common to said first main and complementary stiffening elements to another first radially outer anchoring point (58G’’) of said radially outer portion (545D) of said first complementary stiffening element having a second azimuth (AZSG) circumferentially offset with respect to the first azimuth (AZPG).  

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