Tyre comprising a stiffening structure with irregular anchoring

Abstract

The tyre (10) comprises a crown (12), sidewalls, beads and first stiffening elements (54A) each extending in the first sidewall and / or bead from a first radially inner anchoring point and arranged in first groups (60A) each delimited circumferentially by two first end stiffening elements (541A, 542A). The first radially inner anchoring points of the first stiffening elements (54A) of each first group (60A) are distributed circumferentially with a first constant angular pitch. The angular pitch separating two adjacent first end stiffening elements (541A, 542A) is different from the first constant angular pitch.

Description

[0001] DESCRIPTION

[0002] TITLE: Pneumatic comprising a stiffening structure with irregular anchoring

[0003] Technical field

[0004] The present invention relates to a tire, in particular for a passenger vehicle.

[0005] A tire is understood to mean a bandage intended to form a cavity by cooperating with a mounting support, for example a rim, this cavity being capable of being pressurized to a pressure higher than atmospheric pressure. A tire has a structure of substantially toroidal shape of revolution around a main axis of the tire, this main axis being coincident with the axis of rotation of the tire.

[0006] Previous techniques

[0007] Known from the state of the art is a tire intended to equip a passenger vehicle and described in WO2020 / 128225 and WO2022 / 200717. The tire described comprises a crown extended radially inwards respectively on each side of the median plane of the tire by first and second sidewalls then by first and second beads intended to come into contact with a mounting support, for example a rim.

[0008] The tire includes an internal surface delimiting a toric cavity for inflating the tire once the latter is mounted on the mounting support.

[0009] The tire comprises a stiffening structure comprising first stiffening elements extending continuously in the toric cavity from the first bead to the crown and second stiffening elements extending continuously in the toric cavity from the second bead to the crown.

[0010] Each first and second stiffening element is integral with each bead and the crown of the tire. A tool and a method for manufacturing such a tire are further described in WO2022 / 200717. The tool comprises a core comprising subassemblies divided into so-called "key" sectors and so-called "arch" sectors. The inventors have noted that the manufacture of the tire by using the keys and arches of the tool induces an acoustic signature specific to the process. More generally, each manufacturing process, whether it uses a tool such as described in WO2022 / 200717 or not, induces an acoustic signature specific to this process which it is desirable to reduce, regardless of the process and the tool used in this process.

[0011] The invention aims to enable the reduction of the specific acoustic signature of the manufacturing process on the tire.

[0012] Statement of the invention

[0013] A first subject of the invention relates to a tire comprising a crown, first and second sidewalls each extending the crown radially inward, first and second beads respectively extending the first and second sidewalls radially inward, the tire being provided with an internal surface delimiting a toric inflation cavity of the tire, the tire comprising a stiffening structure comprising a plurality of first stiffening elements each extending continuously in the toric cavity from at least the first sidewall and / or bead from a first radially internal anchoring point to at least the crown.

[0014] The first stiffening elements are arranged in first groups of first stiffening elements adjacent to each other in the circumferential direction of the tire.

[0015] Each first group is circumferentially delimited by two first end stiffening elements.

[0016] The first radially interior anchor points of the first stiffening elements of each first group are distributed circumferentially according to a first constant interior angular pitch.

[0017] The first internal angular pitch separating on the one hand the first radially internal anchoring point of each first end stiffening element of one of the first groups and on the other hand the first radially internal anchoring point of the first end stiffening element of another first group, which is adjacent to said first end stiffening element, is different from the first constant internal angular pitch.

[0018] A second object of the invention relates to a tire comprising a crown, first and second sidewalls each extending the crown radially inward, first and second beads respectively extending the first and second sidewalls radially inward, the tire being provided with an internal surface delimiting a toric inflation cavity of the tire, the tire comprising a stiffening structure comprising a plurality of first stiffening elements each extending continuously in the toric cavity from at least the first sidewall and / or bead to at least the crown up to a first radially outer anchoring point.

[0019] The first stiffening elements are arranged in first groups of first stiffening elements adjacent to each other in the circumferential direction of the tire.

[0020] Each first group is circumferentially delimited by two first end stiffening elements.

[0021] The first radially outer anchor points of the first stiffening elements of each first group are distributed circumferentially according to a first constant outer angular pitch.

[0022] The first outer angular pitch separating on the one hand the first radially outer anchoring point of each first end stiffening element of one of the first groups and on the other hand the first radially outer anchoring point of the first end stiffening element of another first group, which is adjacent to said first end stiffening element, is different from the first constant outer angular pitch.

[0023] As explained below, the invention works as soon as it is applied to only one side of the tire, here at least on the side comprising the first sidewall and / or bead. Advantageous embodiments teach to also apply the invention to both sides of the tire without this being necessary to carry out the invention. Thus, in the present application, the use of the qualifier "first" or "first" aims, unless there is an obvious different interpretation, to associate the element qualified as "first" or "first" with the first sidewall and / or bead. Similarly, the use of the qualifier "second" aims, unless there is an obvious different interpretation, to associate the element qualified as "second" with the second sidewall and / or bead.

[0024] A stiffening element is circumferentially adjacent to another stiffening element means that the stiffening element is the stiffening element circumferentially closest to the other first stiffening element when moving circumferentially in the counterclockwise direction or in the counterclockwise direction from the other stiffening element. Thus, each stiffening element is adjacent to two stiffening elements.

[0025] Angular pitch means the angle separating the two radial planes passing through and parallel to the axis of rotation of the tire and passing through the anchor points concerned.

[0026] The inventors behind the invention discovered that the acoustic signature of the process resulted in the presence of local roundness defects in the tire. By locally modifying the arrangement of the stiffening elements at their radially inner and / or outer anchorage, the force exerted by the stiffening structure on the rest of the tire is locally modified. Thus, the roundness defects of the tire can be corrected where they are located, which makes it possible to reduce the specific acoustic signature of the tire manufacturing process.In a preferred embodiment of the two objects of the invention in which the stiffening structure performs its function on either side of the median plane of the tire, the stiffening structure comprises a plurality of second stiffening elements each extending continuously in the toric cavity from at least the second sidewall and / or bead from a second radially inner anchoring point to at least the crown.

[0027] The second stiffening elements are arranged in second groups of second stiffening elements adjacent to each other in the circumferential direction of the tire.

[0028] Each second group is circumferentially delimited by two second end stiffening elements.

[0029] The second radially interior anchor points of the second stiffening elements of each second group are distributed circumferentially according to a second constant interior angular pitch.

[0030] The second internal angular pitch separating on the one hand the second radially internal anchoring point of each second end stiffening element of one of the second groups and on the other hand the second radially internal anchoring point of the second end stiffening element of another second group, which is adjacent to said second end stiffening element, is different from the second constant internal angular pitch.

[0031] In a preferred embodiment of the two objects of the invention in which the stiffening structure performs its function on either side of the median plane of the tire, the stiffening structure comprises a plurality of second stiffening elements each extending continuously in the toric cavity from at least the second sidewall and / or bead to at least the crown to a second radially outer anchoring point.

[0032] The second stiffening elements are arranged in second groups of second stiffening elements adjacent to each other in the circumferential direction of the tire. Each second group is circumferentially delimited by two second end stiffening elements.

[0033] The second radially outer anchor points of the second stiffening elements of each second group are distributed circumferentially according to a second constant outer angular pitch.

[0034] The second outer angular pitch separating on the one hand the second radially outer anchoring point of each second end stiffening element of one of the second groups and on the other hand the second radially outer anchoring point of the second end stiffening element of another second group, which is adjacent to said second end stiffening element, is different from the second constant outer angular pitch.

[0035] In variants of each of the first and second objects, the internal or external angular pitch separating on the one hand the radially internal or external anchoring point of each end stiffening element of one of the groups and on the other hand the radially internal or external anchoring point of the end stiffening element of another group, which is adjacent to said end stiffening element, is strictly greater than the constant internal or external angular pitch.

[0036] In other variants of each of the first and second objects, the internal or external angular pitch separating on the one hand the radially internal or external anchoring point of each end stiffening element of one of the groups and on the other hand the radially internal or external anchoring point of the end stiffening element of another group, which is adjacent to said end stiffening element, is strictly less than the constant internal or external angular pitch.

[0037] In still other variants of each of the first and second objects, the inner or outer angular pitch separating on the one hand the radially inner or outer anchoring point of one of the end stiffening elements of one of the groups and on the other hand the radially inner or outer anchoring point of the end stiffening element of another group, which is adjacent to said end stiffening element, is strictly greater than the constant inner or outer angular pitch and the inner or outer angular pitch separating on the one hand the radially inner or outer anchoring point of the other of the end stiffening elements of said group and on the other hand the radially inner or outer anchoring point of the end stiffening element of yet another group, which is adjacent to said other end stiffening element,is strictly less than the constant internal or external angular pitch.,

[0038] In variants of each of the first and second objects, the inner or outer angular pitch separating on the one hand the radially inner or outer anchoring point of one of the end stiffening elements of one of the groups and on the other hand the radially inner or outer anchoring point of the end stiffening element of another group, which is adjacent to said end stiffening element, is equal to the inner or outer angular pitch separating on the one hand the radially inner or outer anchoring point of the other of the end stiffening elements of said group and on the other hand the radially inner or outer anchoring point of the end stiffening element of yet another group, which is adjacent to said other end stiffening element.

[0039] In other variants of each of the first and second objects, the inner or outer angular pitch separating on the one hand the radially inner or outer anchoring point of one of the end stiffening elements of one of the groups and on the other hand the radially inner or outer anchoring point of the end stiffening element of another group, which is adjacent to said end stiffening element, is different from, for example greater than, the inner or outer angular pitch separating on the one hand the radially inner or outer anchoring point of the other of the end stiffening elements of said group and on the other hand the radially inner or outer anchoring point of the end stiffening element of yet another group, which is adjacent to said other end stiffening element.

[0040] The toric inflation cavity is intended to be pressurized by an inflation gas once the tire is mounted on a mounting support, most often a rim.

[0041] Among other advantages, the stiffening structure makes it possible to simultaneously increase the radial stiffness, the axial stiffness and the drift stiffness of the tire compared to a conventional tire not comprising a stiffening structure but also compared to tires comprising other stiffening structures, such as that described in W02017 / 005713.

[0042] By increasing the radial rigidity, the stiffening structure limits the radial deformation of the crown, during rolling, and in particular, the counter-deflection, that is to say the radial deformation, opposite the contact area of ​​the rolling surface in contact with the ground. Thus, during the rolling of the tire, during the wheel revolution, the stiffening structure makes it possible to limit the amplitude of the cyclic deformations of the tire, and in particular of its tread, and therefore to limit the resulting energy dissipation, which contributes to the reduction of the rolling resistance. In addition, under radial stress, the value of the contact area with the ground is not modified, which makes it possible to maintain the same grip performance as for the tire described in W02017 / 005713.

[0043] By increasing axial stiffness and drift stiffness, the stiffening structure will contribute to improving behavior under transverse stress, for example when drifting. In addition, under transverse stress, the contact area with the ground ensures a more homogeneous distribution of contact pressures, which increases transverse grip.

[0044] Furthermore, the stiffening structure participates at least partially in carrying the load applied to the tire such that this applied load is taken up jointly by the tire, thanks to its pneumatic rigidity and its intrinsic structural rigidity and by the stiffening structure. Thus, when the tire is subjected to a nominal radial load, a portion of the stiffening structure arranged opposite the contact area is put under tension. In certain embodiments, conversely, a portion of the stiffening structure arranged opposite the contact area is subjected to compression buckling.

[0045] The presence of the stiffening structure thus makes it possible to reduce the tire's contribution to carrying the load and therefore to be able to reduce its structural rigidity, for example by reducing the volume of the beads. Indeed, the beads of a conventional tire dissipate a significant quantity of energy, due to their volume and the hysteretic nature of their constituent elastomeric mixture. Reducing their volume thus makes it possible to significantly reduce rolling resistance.

[0046] The tire according to the invention has a substantially toric shape around an axis of revolution substantially coincident with the axis of rotation of the tire. This axis of revolution defines three directions conventionally used by those skilled in the art: an axial direction, a circumferential direction and a radial direction.

[0047] By axial direction is meant the direction substantially parallel to the axis of revolution of the tire, that is to say the axis of rotation of the tire.

[0048] By circumferential direction is meant the direction which is substantially perpendicular to both the axial direction and a radius of the tire (in other words, tangent to a circle whose center is on the axis of rotation of the tire).

[0049] By radial direction is meant the direction along a radius of the tire, that is to say any direction intersecting the axis of rotation of the tire and substantially perpendicular to this axis.

[0050] By median plane of the tire, denoted M, is meant the plane perpendicular to the axis of rotation of the tire which is located at the axial mid-distance of the two beads and passes through the axial center of the crown reinforcement. By equatorial circumferential plane of the tire, denoted E, is meant, in a meridian section plane, the plane passing through the equator of the tire, perpendicular to the median plane and to the radial direction. The equator of the tire is, in a meridian section plane (plane perpendicular to the circumferential direction and parallel to the radial and axial directions) the axis parallel to the axis of rotation of the tire and located equidistant between the radially outermost point of the tread intended to be in contact with the ground and the radially innermost point of the tire intended to be in contact with a support, for example a rim.

[0051] By meridian plane is meant a plane parallel to and containing the axis of rotation of the tire and perpendicular to the circumferential direction.

[0052] By radially inner, respectively radially outer, is meant closer to the axis of rotation of the tire, respectively further from the axis of rotation of the tire. By axially inner, respectively axially outer, is meant closer to the median plane of the tire, respectively further from the median plane of the tire.

[0053] By bead is meant the radial portion of the tire intended to allow the tire to be attached to a mounting support, for example a wheel comprising a rim. Thus, each bead is in particular intended to be in contact with a hook of the rim allowing it to be attached. The bead is thus delimited radially internally by the radially inner end of the tire and radially externally by an axial line passing through the radially outermost point in contact with a standard rim within the meaning of the standard of the European Tire and Rim Technical Organization or "ETRTO", 2023.

[0054] The sidewall is the radial portion of the tire connecting the bead to the crown. The sidewall is delimited radially externally by a tread edge. The axial edges of the tread are determined on a tire mounted on a nominal rim and inflated to the nominal pressure as defined in the ETRTO 2023 standard manual. The edges are arranged on either side of the median plane of the tire and formed by lines substantially parallel to the circumferential direction of the tire. In the case of an obvious boundary between the tread and the sidewall of the tire, the edges are determined simply. In the case where the tread is continuous with the sidewalls, the edges are usually determined by loading the tire to 80% of its load capacity according to the ETRTO 2023 standard manual and the edges are identified as the axial limits of the tread in contact with the ground.The sidewall is delimited radially internally by an axial line passing through the radially outermost point in contact with a standard rim within the meaning of the European Tyre and Rim Technical Organisation or “ETRTO” standard, 2023.

[0055] Any interval of values ​​designated by the expression "between a and b" represents the domain of values ​​from greater than a to less than b (i.e., excluding the limits a and b), while any interval of values ​​designated by the expression "from a to b" signifies the domain of values ​​from a to b (i.e., including the strict limits a and b).

[0056] The tires of the invention are preferably intended for passenger vehicles as defined within the meaning of the standard of the European Tyre and Rim Technical Organization or "ETRTO", 2023. Such a tire has a section in a meridian cutting plane characterized by a section height H and a nominal section width SW within the meaning of the standard of the European Tyre and Rim Technical Organization or "ETRTO", 2023. The values ​​of SW and H are indicated on the marking of the sidewall of the tire, for example as defined according to the ETRTO manual, 2023.

[0057] Preferably, the passenger vehicle tires to which the invention will advantageously be applied are such that the H / S ratio, expressed as a percentage, is at most equal to 90 and 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. In addition, the hook diameter D, defining the diameter of the rim on which the tire is mounted, is at least equal to 12 inches and at most equal to 30 inches.

[0058] Conventionally, in a tire comprising a crown reinforcement and a carcass reinforcement, the crown comprises a tread intended to come into contact with the rolling ground 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 inside the crown reinforcement. Conventionally, the crown reinforcement comprises at least one crown layer comprising reinforcing elements. These reinforcing elements are preferably textile or metal wire elements.

[0059] In embodiments allowing the performance of so-called radial tires to be obtained as defined by the ETRTO, the carcass reinforcement comprises at least one carcass layer, said carcass layer comprising carcass wire reinforcement elements, each carcass wire reinforcement element extending substantially in a main direction forming with the circumferential direction of the tire, an angle, in absolute value, ranging from 80° to 90°. As a variant, it will be possible to have a variable angle ranging from 80° to 90° in at least one part of the sidewall and strictly less than 80° in at least one part of the crown.

[0060] In an advantageous embodiment, the stiffening structure is not sealed against an inflation gas of the tire. Thus, the stiffening structure allows the inflation gas to pass through. In other words, the stiffening structure does not delimit a secondary cavity under pressure of the tire. By "not sealed", it is understood that the stiffening structure is permeable to the inflation gas so that the pressure is homogeneous in the toric cavity at all times and, in particular during inflation of the tire.

[0061] Optionally, each first stiffening element of said first group extends in a main direction forming with the radial direction of the tire an angle of inclination such that at least two first stiffening elements of said first group extend at different angles of inclination.

[0062] In a variant, each second stiffening element of said second group extends in a main direction forming with the radial direction of the tire an angle of inclination such that at least two second stiffening elements of said second group extend at different angles of inclination.

[0063] In a preferred embodiment making it possible to continuously vary the force exerted by the stiffening structure on the rest of the tire, each first stiffening element of said first group extends in a main direction forming with the radial direction of the tire an angle of inclination such that:

[0064] - the angles of inclination decrease when moving circumferentially from one of the two first end stiffening elements of said first group towards a first intermediate stiffening element of said first group between the two first end stiffening elements of said first group,

[0065] - the angles of inclination are increasing when moving circumferentially from a first intermediate stiffening element between the two first end stiffening elements of said first group towards the other of the two first end stiffening elements of said first group.

[0066] In a variant also making it possible to continuously vary the force exerted by the stiffening structure on the rest of the tire, each second stiffening element of said second group extends in a main direction forming with the radial direction of the tire an angle of inclination such that:

[0067] - the angles of inclination are decreasing when moving circumferentially from one of the two second end stiffening elements of said second group towards a second intermediate stiffening element of said second group between the two second end stiffening elements of said second group, - the angles of inclination are increasing when moving circumferentially from the second intermediate stiffening element between the two second end stiffening elements of said second group towards the other of the two second end stiffening elements of said second group.

[0068] Optionally, each first stiffening element is anchored in the vertex from a first radially outer anchor point, the first radially outer anchor points of the first stiffening elements of each first group being distributed circumferentially according to a first constant outer angular pitch.

[0069] In a variant, each second stiffening element is anchored in the vertex from a second radially outer anchoring point, the second radially outer anchoring points of the second stiffening elements of each second group being distributed circumferentially according to a second constant outer angular pitch.

[0070] Optionally and not compatible with the second subject of the invention, all of the first radially external anchoring points of the first stiffening elements are distributed circumferentially according to a first constant external angular pitch.

[0071] In a variant not compatible with the second object of the invention, all of the second radially external anchoring points of the second stiffening elements are distributed circumferentially according to a second constant external angular pitch.

[0072] Optionally, each first stiffening element is anchored in the first sidewall and / or bead from a first radially inner anchoring point, the first radially inner anchoring points of the first stiffening elements of each first group being distributed circumferentially according to a first constant inner angular pitch. In a variant, each second stiffening element is anchored in the second sidewall and / or bead from a second radially inner anchoring point, the second radially inner anchoring points of the second stiffening elements of each second group being distributed circumferentially according to a second constant inner angular pitch.

[0073] Optionally and not compatible with the first subject of the invention, all of the first radially interior anchoring points of the first stiffening elements are distributed circumferentially according to a first constant interior angular pitch.

[0074] In a variant not compatible with the first object of the invention, all of the second radially interior anchoring points of the second stiffening elements are distributed circumferentially according to a second constant interior angular pitch.

[0075] Optionally, each first stiffening element of said first group extends in a main direction forming with the radial direction of the tire an angle of inclination such that the angle of inclination of at least one first intermediate stiffening element between the first end stiffening elements of said first group is, in absolute value less than or equal to 2°, in particular a substantially zero angle.

[0076] In a variant of the second design, each second stiffening element of said second group extends in a main direction forming with the radial direction of the tire an angle of inclination such that the angle of inclination of at least one second intermediate stiffening element between the second end stiffening elements of said second group is, in absolute value less than or equal to 2°, in particular a substantially zero angle.

[0077] Optionally, the first two end stiffening elements of each first group extend in a main direction forming, with the radial direction of the tire, an angle in absolute value ranging from 5° to 20°, in particular ranging from 10° to 20°, more particularly ranging from 15° to 20°.

[0078] In a variant, the two second end stiffening elements of each second group extend in a main direction forming, with the radial direction of the tire, an angle in absolute value ranging from 5° to 20°, in particular ranging from 10° to 20°, more particularly ranging from 15° to 20°.

[0079] Optionally, the first groups comprise at least one first primary group and at least one first secondary group, the or each first primary group comprising a number of first stiffening elements strictly greater than the number of first stiffening elements of the or each first secondary group.

[0080] In a variant, the second groups comprise at least one second primary group and at least one second secondary group, the or each second primary group comprising a number of second stiffening elements strictly greater than the number of second stiffening elements of the or each second secondary group.

[0081] Optionally, the first groups comprise several primary and secondary first groups arranged alternately along the circumferential direction of the tire.

[0082] In one variant, the second groups comprise several second primary and secondary groups arranged alternately along the circumferential direction of the tire.

[0083] Optionally, each first stiffening element is anchored in the first sidewall and / or bead by extending into the first sidewall and / or bead. Advantageously, each second stiffening element is anchored in the second sidewall and / or bead by extending into the second sidewall and / or bead. Thus, the endurance of the anchoring of the stiffening structure in each sidewall and / or bead concerned is improved.

[0084] Optionally, the first and / or second radially inner anchoring point is a point on the inner surface of the tire. Optionally, each first stiffening element is anchored in the crown by extending into the crown. Advantageously, each second stiffening element is anchored in the crown by extending into the crown. Thus, the endurance of the anchoring of the stiffening structure in the crown is improved.

[0085] Optionally, the first and / or second radially outer anchor point is a point on the inner surface of the tire.

[0086] Advantageously, each first stiffening element comprises a portion extending continuously in the toric cavity from the first radially inner anchoring point to the first radially outer anchoring point.

[0087] Advantageously, each first stiffening element comprises a radially outer anchoring portion extending from the first radially outer anchoring point in the apex and extending the portion extending continuously into the toric cavity.

[0088] Advantageously, each first stiffening element comprises a radially inner anchoring portion extending from the first radially inner anchoring point in the first sidewall and / or bead and extending the portion extending continuously in the toric cavity.

[0089] Advantageously, each second stiffening element comprises a portion extending continuously in the toric cavity from the second radially inner anchoring point to the second radially outer anchoring point.

[0090] Advantageously, each second stiffening element comprises a radially outer anchoring portion extending from the second radially outer anchoring point in the apex and extending the portion extending continuously in the toric cavity.

[0091] Advantageously, each second stiffening element comprises a radially inner anchoring portion extending from the second radially inner anchoring point in the second sidewall and / or bead and extending the portion extending continuously in the toric cavity.

[0092] Preferably, each first stiffening element extending from the first sidewall and / or bead to the top or said radially inner anchoring portion of each first stiffening element is anchored in the first sidewall and / or bead by 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, each first stiffening element extending from the first sidewall and / or bead to the top or said radially outer anchoring portion of each first stiffening element is anchored in the top by being anchored in or around one or more radially outer reinforcing structures of the stiffening structure arranged in the top.

[0093] Alternatively, each first stiffening element extending from the first sidewall and / or bead to the top or said radially inner anchoring portion of each first stiffening element is anchored in the first sidewall and / or bead by being anchored in an elastomeric mass of said first sidewall and / or bead. Also as a variant, each first stiffening element extending from the first sidewall and / or bead to the top or said radially outer anchoring portion of each first stiffening element is anchored in the top by being anchored in an elastomeric mass of said top.

[0094] Optionally, each second stiffening element extending from the second flank and / or bead to the top or said radially inner anchoring portion of each second stiffening element is anchored in the second flank and / or bead by being anchored in or around a second radially inner reinforcing structure of the stiffening structure arranged in the second flank and / or bead. Also optionally, each second stiffening element extending from the second flank and / or bead to the top or said radially outer anchoring portion of each second stiffening element is anchored in the top by being anchored in or around one or more radially outer reinforcing structures of the stiffening structure arranged in the top.

[0095] Alternatively, each second stiffening element extending from the second sidewall and / or bead to the top or said radially inner anchoring portion of each second stiffening element is anchored in the second sidewall and / or bead by being anchored in an elastomeric mass of said second sidewall and / or bead. Also as a variant, each second stiffening element extending from the second sidewall and / or bead to the top or said radially outer anchoring portion of each second stiffening element is anchored in the top by being anchored in an elastomeric mass of said top.

[0096] Of course, the tire may comprise both the first and second radially inner reinforcing structures and the radially outer reinforcing structure(s) or only the first and second radially inner reinforcing structures or only the radially outer reinforcing structure(s).

[0097] Each radially inner or outer reinforcing structure is respectively arranged in the corresponding flank and / or bead or in the crown, that is to say arranged radially inside the internal surface and embedded in the mass of materials constituting the corresponding flank and / or bead or the crown. The stiffening structure passes through the internal surface to be anchored in or around the corresponding radially inner reinforcing structure and / or through the internal surface to be anchored in or around the or one of the radially outer reinforcing structure(s).

[0098] As indicated previously, 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, that is to say that the stiffening structure penetrates at least partially into said reinforcing structure, or even passes completely through it so that said reinforcing structure forms a mechanical anchoring of the stiffening structure.

[0099] In particular, in the case where said reinforcing structure is an assembly of several wire elements, the stiffening structure is "anchored in the structure" means, for example, that the stiffening structure wraps around certain wire elements of said reinforcing structure so as to pass through it.

[0100] In a second variant, the stiffening structure can be anchored around the very structure of said reinforcing structure, that is to say that the stiffening structure bears on said reinforcing structure so that said reinforcing structure absorbs part of the forces exerted on the stiffening structure and anchors the stiffening structure in the sidewall and / or the bead or the crown.

[0101] In particular, in the case where said reinforcing structure is an assembly of several wire elements, the stiffening structure is "anchored around the structure" means, for example, that the stiffening structure wraps around the peripheral wire elements of said reinforcing structure without passing through it.

[0102] In the embodiments comprising a first radially internal reinforcement structure arranged in the first sidewall and / or bead, the latter preferably comprises at least one first radially internal circumferential reinforcement element allowing the anchoring of the stiffening structure.

[0103] In the embodiments comprising a second radially internal reinforcement structure arranged in the second sidewall and / or bead, the latter preferably comprises at least one second radially internal circumferential reinforcement element allowing the anchoring of the stiffening structure.

[0104] In a preferred variant, each first and second bead respectively comprises a first and second radially inner circumferential reinforcing element intended to allow the tire to be attached to a tire mounting support, 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 intended to allow the tire to be attached to a tire mounting support.

[0105] Thus, the propagation of noise generated by the stiffening structure from the stiffening structure to the vehicle through the tire mounting bracket is reduced. In fact, the noise generated by the stiffening structure is damped by the tire structure separating the radially inner circumferential reinforcing element in question from the radially inner circumferential reinforcing element intended to allow the tire to be attached to a tire mounting bracket located on the same side of the median plane of the tire.

[0106] This damping is the result of the fact that the radially inner circumferential reinforcing element considered is mechanically decoupled from said radially inner circumferential reinforcing element intended to allow the tire to be attached to a tire mounting support located on the same side of the median plane of the tire.

[0107] Alternatively, said first radially inner circumferential reinforcing element or each first and second radially inner circumferential reinforcing element is intended to allow the tire to be attached to a tire mounting support.

[0108] In one embodiment, said first radially inner circumferential reinforcing element or each first and second radially inner circumferential reinforcing element is a wire reinforcing element extending in a main direction forming with the circumferential direction of the tire an angle less than or equal to 10°, preferably less than or equal to 5° and more preferably substantially zero.

[0109] In the embodiments comprising at least one radially outer reinforcing structure arranged in the crown, the latter preferably comprises at least one radially outer circumferential reinforcing element.

[0110] In one embodiment, said radially outer circumferential reinforcing element of the or each radially outer reinforcing structure is a wire reinforcing element extending in a main direction forming with the circumferential direction of the tire an angle less than or equal to 10°, preferably less than or equal to 5° and more preferably substantially zero.

[0111] In some embodiments, the tire comprises first and second radially outer reinforcing structures. In these embodiments, preferably, each first and second radially outer reinforcing structure respectively comprises a first and second radially outer circumferential reinforcing element, the first radially outer circumferential reinforcing element being arranged axially spaced from said second radially outer circumferential reinforcing element.

[0112] This makes it possible to reduce the mass of the reinforcement structure allowing the anchoring of the stiffening structure in the crown and to limit the over-frettage of the crown, thus making it possible to maintain a regular contact area.

[0113] Preferably, the first radially outer circumferential reinforcing element and the second radially outer circumferential reinforcing element are arranged on either side of the median plane of the tire.

[0114] This improves the axial distribution of the forces exerted by the stiffening structure on the top.

[0115] Each radially inner circumferential reinforcing element and each radially outer circumferential reinforcing element may be wound in different ways such as described in particular in WO2022 / 200717. Of course, the tire may comprise several of said first and / or second radially inner and / or outer reinforcing structures.

[0116] Advantageously, the first radially inner anchoring point of each first stiffening element and the first radially outer anchoring point of each first stiffening element are arranged on the same side of the median plane of the tire.

[0117] Optionally, the second radially inner anchoring point of each second stiffening element and the second radially outer anchoring point of each second stiffening element are arranged on the same other side of the median plane of the tire.

[0118] 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 median plane and on the other hand, between a radially inner anchoring point and a radially outer anchoring point located on the other side of the median plane, do not cross, which makes it possible to limit the axial buckling of the tread, that is to say the axial compression of the tread, in particular under conditions of high lateral stresses. Thus, on the one hand, a regular contact area is maintained, and on the other hand, the risk of deterioration of the crown reinforcement of the tire is reduced, in particular by avoiding the compression of the various constituent elements of the crown reinforcement, for example the textile and metal wire reinforcement elements of the crown reinforcement.

[0119] In a first configuration of the stiffening elements, each first stiffening element forms a first continuous stiffening element which winds at least from the first sidewall and / or bead through the crown. Also preferably, each second stiffening element forms a second continuous stiffening element which winds at least from the second sidewall and / or bead through the crown. Thus, the manufacture of the tire is facilitated and the robustness of the stiffening structure is improved by removing 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 thus possible to have a continuous stiffening element extending over the entire circumference of the tire.The said stiffening element of the stiffening structure being continuous, the transmission of forces between each sidewall and / or bead is improved, the transmission of forces being thus distributed over the tire. Thus, the stiffening structure performs its function over the entire circumference of the tire.

[0120] According to a first variant of the first configuration of the stiffening elements, said first and second stiffening elements form a continuous stiffening element which extends continuously from the first flank and / or bead towards the second flank and / or bead via the top so as to snake from the first flank and / or bead to the second flank and / or bead.

[0121] According to a second variant of the first configuration of the stiffening elements, each first stiffening element forms a continuous stiffening element which winds between the first sidewall and / or bead and the crown. Still in this second variant, each second stiffening element forms a continuous stiffening element which winds between the second sidewall and / or bead and the crown.

[0122] In a second configuration of the stiffening elements, it may be envisaged that each first stiffening element extends from the first sidewall and / or bead to the top and has one end in the first sidewall and / or bead. Similarly, it may be envisaged that each second stiffening element extends from the second sidewall and / or bead to the top and has one end in the second sidewall and / or bead.

[0123] In a first variant of this second configuration, it may be envisaged that each first stiffening element extends from the first sidewall and / or bead to the top and has one end in the top. Similarly, it may be envisaged that each second stiffening element extends from the second sidewall and / or bead to the top and has one end in the top.

[0124] In a second variant of this second configuration, each first stiffening element is respectively each second stiffening element and extends from the first flank and / or bead to the second flank and / or bead via the top and has an end in each first and second flank and / or bead.

[0125] Each stiffening element according to one of the designs or configurations previously defined can be characterized geometrically, in particular by its mean section Sm, this characteristic not necessarily being identical for all the stiffening elements. The mean section Sm is the average of the sections obtained by cutting the stiffening element by all the cylindrical surfaces, coaxial with the tire and radially included in the internal toric 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 includes a largest characteristic dimension Dmax and a smallest characteristic dimension Dmin, the ratio of which R= Dmax / Dmin is called the form ratio.As examples, a stiffening element having a circular mean section Sm, having a diameter equal to d, has a shape ratio R=l, a stiffening element having a rectangular mean section Sm, having a length L and a width 1, has a shape ratio R=L / 1, and a stiffening element having an elliptical mean section Sm, having a major axis D and a minor axis d, has a shape ratio R=D / d.

[0126] A first type of preferred stiffening element, with a shape ratio R at most equal to 3, is said to be one-dimensional. In other words, a stiffening element is considered 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 has a wire-like mechanical behavior, that is to say that it can only be subjected to extension or compression forces along its mean line. This is the reason why a one-dimensional stiffening element is usually called a wire-like stiffening element.Among the components commonly used in the field of tires, textile wire elements, consisting of an assembly of elementary textile monofilaments, or metal cables, consisting of an assembly of elementary metal monofilaments, can be considered as one-dimensional stiffening elements, because their average section Sm being substantially circular, the aspect ratio R is equal to 1, therefore less than 3.

[0127] 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 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 has membrane-type mechanical behavior, i.e. it can only be subjected to extension or compression forces in 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 two-dimensional of the strip type. According to a second variant, a stiffening element, with an aspect ratio R at least equal to 50, is said to be two-dimensional of the film type.

[0128] The materials that can be used for each stiffening element are as described in W02022 / 200717.

[0129] In a very advantageous embodiment, each first and / or second stiffening element is respectively a first and / or second wire stiffening element, preferably a first and / or second textile wire stiffening element. Preferably, the wire stiffening elements are identical, that is to say they have identical geometric characteristics and constituent materials.

[0130] These stiffening wire elements are usually called stays. The advantage of using stiffening wire elements is to have a stiffening structure with low mass and low hysteresis. The use of identical stiffening wire elements allows for a homogeneous distribution of forces between the stiffening elements.

[0131] By textile is meant that each wire stiffening element is non-metallic, for example made of a material chosen from a polyester, a polyamide, a polyketone, a polyvinyl alcohol, a cellulose, a mineral fiber, a natural fiber, an elastomeric material or a mixture of these materials. Polyesters include, for example, PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PBT (polybutylene terephthalate), PBN (polybutylene naphthalate), PPT (polypropylene terephthalate), PPN (polypropylene naphthalate). Polyamides include aliphatic polyamides such as polyamides 4-6, 6, 6-6 (nylon), 1 1 or 12 and aromatic polyamides such as aramid. Preferably, the material is a polyester or an aliphatic polyamide.

[0132] Brief description of the drawings

[0133] The present invention will be better understood upon studying the detailed description of embodiments, taken as non-limiting examples and illustrated by the appended drawings in which:

[0134] [Fig 1] is a view of a tire in a meridian section plane parallel to the axis of rotation according to a first exemplary embodiment of the invention;

[0135] [Fig 2] and [Fig 3] are schematic representations of the anchoring of the stiffening structure of Figure 1 in the first and second beads respectively and in the crown of the tire of Figure 1;

[0136] [Fig 4] is a schematic representation of a state-of-the-art tire illustrating roundness defects;

[0137] [Fig 5] is a schematic representation of the tire of [Fig 1 ] to [Fig 3 ] illustrating the reduction of roundness defects;

[0138] [Fig 6] is a view similar to that of [Fig 2] of a tire according to a second exemplary embodiment of the invention; and

[0139] [Fig 7] is a view similar to that of [Fig 2] of a tire according to a third exemplary embodiment of the invention.

[0140] Detailed description

[0141] In the figures relating to the tire, a reference X, Y, Z is shown corresponding to the usual axial (Y), radial (Z) and circumferential (X) directions of a tire.

[0142] The figures represent a tire 10 having a substantially toric shape around an axis of revolution substantially parallel to the axial direction Y. The tire 10 is intended for a passenger vehicle and has a dimension of 275 / 35ZR19. In the various figures, the tire 10 is shown in new condition, that is to say not having yet been driven.

[0143] The tire 10 according to the first embodiment described with reference to FIGS. 1 to 3 comprises a crown 12 comprising a tread 14 intended to come into contact with a ground when rolling and a crown reinforcement 16 extending in the crown 12 in the circumferential direction X. The tire 10 also comprises an inner layer 18.

[0144] The tire 10 further comprises a crown reinforcement identical to that described in WO2022 / 200717 comprising a working reinforcement 20 comprising working layers 24, 26 as well as a hoop reinforcement 22 comprising a hoop layer 28.

[0145] The tire 10 comprises first and second sidewalls 30A, 30B extending the crown 12 radially inwards. The second sidewall 30B is opposite the first sidewall 30A relative to the median plane M. The tire 10 further comprises first and second beads 32A, 32B extending each first and second sidewall 30A, 30B radially inwards respectively. The second bead 32B is opposite the first bead 32A relative to the median plane M. Each first and second sidewall 30A, 30B respectively connects each first and second bead 32A, 32B to the crown 12. The tire 10 is provided with an internal surface 34, intended to be in contact with the inflation gas of the tire, and which delimits a toric cavity 36 for inflation of the tire 10. The internal surface 34 is here carried by the inner layer 18.

[0146] The tire 10 comprises first and second radially inner reinforcing structures 38A, 38B respectively arranged in each first and second bead 32A, 32B.

[0147] Each first and second radially inner reinforcing structure 38A, 38B respectively comprises at least first and second radially inner circumferential reinforcing elements 40A, 40B, respectively arranged in each first and second bead 32A, 32B, comprising in particular at least first and second wire reinforcing elements as described in WO2022 / 2007 17.

[0148] Each first and second bead 32A, 32B respectively comprises a first and second radially inner circumferential reinforcing element 42A, 42B, here a bead wire, intended to allow the tire 10 to be attached to a mounting support for the tire 10, for example a rim.

[0149] 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 intended to allow the attachment of the tire 10 to a mounting support for the tire 10.

[0150] The tire 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 median plane M of the tire 10 and here substantially symmetrically with respect to the median plane M of the tire 10. Each first and second radially outer circumferential reinforcing element 46A, 46B is as described in WO2022 / 2007 17.

[0151] The tire 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 intended to allow the tire 10 to be attached to a mounting support for the tire 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 here comprises a single carcass layer 50.

[0152] The tire 10 comprises a stiffening structure 52 extending in the toric cavity 36 from the first bead 32A to the crown 12 and which is anchored in the first bead 32A by being anchored around the first radially inner reinforcing structure 38A. The stiffening structure 52 extends in the toric cavity 36 from the second bead 32B to the crown 12 and is anchored in the second bead 32B by being anchored around the second radially inner reinforcing structure 38B. The stiffening structure 52 extends into the toric cavity 36 from the first bead 32A and from the second bead 32B to the apex 12 and is anchored in the apex 12 by being anchored around the radially outer reinforcing structures 44A, 44B.The stiffening structure 52 comprises a plurality of stiffening elements 54 comprising a plurality of first stiffening elements 54A extending continuously in the toric cavity 36 and a plurality of second stiffening elements 54B extending continuously in the toric cavity 36. The first and second stiffening elements 54A, 54B are distributed circumferentially in the toric cavity 36. The circumferential distribution of the first and second stiffening elements 54A, 54B will be described with reference to FIGS. 2 and 3.

[0153] Each stiffening element 54 is a textile wire stiffening element comprising an assembly of three multifilament strands of aliphatic polyamide, for example nylon, these three multifilament strands being individually helical at 190 turns per meter in one direction and then helical together at 190 turns per meter in the opposite direction. Each of these multifilament strands has a count equal to 188 tex.

[0154] Each first stiffening element 54A extends continuously from the first flank 30A and / or the first bead 32A to the top 12 and here from the first bead 32A to the top 12. Each second stiffening element 54B extends continuously from the second flank 30A and / or the second bead 32A to the top 12 and here from the second bead 32A to the top 12.

[0155] In order to ensure optimal anchoring of the first and second stiffening elements 54A, 54B, 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 and flexion rigidities.

[0156] In order to ensure optimal anchoring of the first and second stiffening elements 54A, 54B, each first and second radially outer reinforcing structure 44A, 44B, in particular each first and second radially outer circumferential reinforcing element 46A, 46B, has a relatively high extension rigidity and a relatively low bending rigidity in order to limit over-shrinking of the crown 12 and not risk damaging the flattening of the tread 14.

[0157] Each first stiffening element 54A is anchored, in the first bead 32A, in or around the first radially inner reinforcing structure 38A. Each second stiffening element 54B is anchored in the second bead 32B, in or around the second radially inner reinforcing structure 38B.

[0158] Each first and second stiffening element 54A, 54B 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. Here, each first and second stiffening element 54A, 54B is wound at least in part respectively around each first and second radially outer circumferential reinforcing element 46A, 46B.

[0159] Each first stiffening element 54A passes through the inner surface 34 at a first radially inner anchoring point 56A in the first bead 32A to be anchored around the first radially inner reinforcing structure 38A and at a first radially outer anchoring point 58A in the crown 12 to be anchored around the first radially outer reinforcing structure 44A. Thus, each first stiffening element 54A is anchored in the first bead 32A by extending into the first bead 32A from the first radially inner anchoring point 56A. Each first stiffening element 54A is anchored in the crown 12 by extending into the crown 12 from the first radially outer anchoring point 58A.

[0160] Each second stiffening element 54B passes through the inner surface 34 at a second radially inner anchoring point 56B in the second bead 32B to be anchored around the second radially inner reinforcing structure 38B and at a second radially outer anchoring point 58B in the crown 12 to be anchored around the second radially outer reinforcing structure 44B. Thus, each second stiffening element 54B is anchored in the second bead 32B by extending into the second bead 32B from the second radially inner anchoring point 56B. Each second stiffening element 54B is anchored in the crown 12 by extending into the crown 12 from the second radially outer anchoring point 58B.

[0161] Each first stiffening element 54A comprises a radially inner anchoring portion 541, a portion 543, and a radially outer anchoring portion 545, the portion 543 being extended on the one hand by the radially inner anchoring portion 541 and on the other hand by the radially outer anchoring portion 545.

[0162] Each second stiffening element 54B comprises a radially inner anchoring portion 542, a portion 544, and a radially outer anchoring portion 546, the portion 544 being extended on the one hand by the radially inner anchoring portion 542 and on the other hand by the radially outer anchoring portion 546.

[0163] The portion 543 of each first stiffening element 54A extends continuously in the toric cavity 36 from the first radially inner anchoring point 56A to the first radially outer anchoring point 58A.

[0164] The portion 544 of each second stiffening element 54B extends continuously in the toric cavity 36 from the second radially inner anchoring point 56B to the second radially outer anchoring point 58B.

[0165] The radially inner anchoring portion 541 of each first stiffening element 54A extends from the first radially inner anchoring point 56A in the first bead 32A to be anchored around the first radially inner reinforcing structure 38A.

[0166] The radially outer anchoring portion 545 of each first stiffening element 54A extends from the first radially outer anchoring point 58A in the apex 12 to be anchored around the first radially outer reinforcing structure 44A.

[0167] The radially inner anchoring portion 542 of each second stiffening element 54B extends from the second radially inner anchoring point 56B in the second bead 32B to be anchored around the second radially inner reinforcing structure 38B.

[0168] The radially outer anchoring portion 546 of each second stiffening element 54B extends from the second radially outer anchoring point 58B in the apex 12 to be anchored around the second radially outer reinforcing structure 44B.

[0169] Each first stiffening element 54A forms a first continuous stiffening element which winds at least from the first bead 32A passing through the apex 12 and each second stiffening element 54B forms a second continuous stiffening element which winds at least from the second bead 32B passing through the apex 12. More precisely, the first and second stiffening elements 54A, 54B form a continuous stiffening element 54 which extends continuously from the first bead 32A to the second bead 32B passing through the apex 12 so as to wind from the first bead 32A to the second bead 32B.

[0170] The first radially outer anchoring point 58A is arranged axially on the same side as the first radially inner anchoring point 56A and as the first radially inner reinforcing structure 38A relative to the median plane M. The second radially outer anchoring point 58B is arranged axially on the same other side as the second radially inner anchoring point 56B and as the second radially inner reinforcing structure 38B relative to the median plane M. Each first and second radially inner anchoring point 56A, 56B and outer 58A, 56B is arranged so that the portions 543, 544 do not intersect in the toric cavity 36.Each first and second stiffening element 54A, 54B is wound in part respectively around each first and second radially inner circumferential reinforcing element 40A, 40B, each first and second radially inner circumferential reinforcing element 40A, 40B being respectively the only radially inner circumferential reinforcing element of each corresponding first and second radially inner reinforcing structure 38A, 38B and being wound circumferentially over a complete turn around the axis of revolution.

[0171] Preferably, the first sidewall 30A and / or bead 32A is arranged on the same side of the median plane of the tire as the inner side of the tire.

[0172] With reference to Figures 2 and 3, the first stiffening elements 54A are arranged in first groups 60A of first stiffening elements 54A adjacent to each other in the circumferential direction of the tire 10 and the second stiffening elements 54B are arranged in second groups 60B of second stiffening elements 54B adjacent to each other in the circumferential direction of the tire 10.

[0173] Each first group 60A is circumferentially delimited by two first end stiffening elements 541A, 542A such that the other first stiffening elements 54A of the first group 60A considered are arranged circumferentially between the two first end stiffening elements 541A, 542A of the first group 60A considered. Similarly, each second group 60B is circumferentially delimited by two second end stiffening elements 541B, 542B such that the other second stiffening elements 54B of the second group 60B considered are arranged circumferentially between the two second end stiffening elements 541B, 542B of the second group 60B considered.

[0174] Thus, the first end stiffening element 541A of a first group 60A, which is the extreme stiffening element of the first group 60A considered in the trigonometric direction, is adjacent to a first end stiffening element 542A of another first group 60A and adjacent to a first stiffening element 54A of the first group 60A considered. Similarly, the first end stiffening element 542A of the first group 60A considered, which is the extreme stiffening element of the first group 60A considered in the anti-trigonometric direction, is adjacent to a first end stiffening element 541A of another first group 60A and adjacent to a first stiffening element 54A of the first group 60A considered.

[0175] Similarly, the second end stiffening element 541B of a second group 60B, which is the extreme stiffening element of the second group 60B considered in the trigonometric direction, is adjacent to a second end stiffening element 542B of another second group 60B and adjacent to a second stiffening element 54B of the second group 60B considered. Similarly, the second end stiffening element 542B of the second group 60B considered, which is the extreme stiffening element of the second group 60B considered in the anti-trigonometric direction, is adjacent to a second end stiffening element 541B of another second group 60B and adjacent to a second stiffening element 54B of the second group 60B considered.

[0176] In the example shown, the first groups 60A comprise first primary groups 601A and first secondary groups 602A. The second stiffening elements 54B comprise second primary groups 601B and second secondary groups 602B.

[0177] Each first and second primary group 601A, 601B respectively comprises a number N 1A, N 1B ​​of first and second stiffening elements 54A, 54B. Each first and second secondary group 602A, 602B respectively comprises a number N2A, N2B of first and second stiffening elements 54A, 54B. Here N 1A=N 1B > N2A=N2B. The first primary and secondary groups 601A, 602A are arranged alternately in the circumferential direction so that when traveling along the tire 10 in the circumferential direction, a first primary group 601A then a first secondary group 602A are encountered alternately. The second primary and secondary groups 601B, 602B are arranged alternately in the circumferential direction so that when traveling along the tire 10 in the circumferential direction, a second primary group 601B and then a second secondary group 602B are encountered alternately.

[0178] The first radially interior anchoring points 56A of the first stiffening elements 54A of each first group 60A are distributed circumferentially according to a first constant interior angular pitch A 1A. The second radially interior anchoring points 56B of the second stiffening elements 54B of each second group 60B are distributed circumferentially according to a second constant interior angular pitch A1 B.

[0179] More precisely, the first and second radially interior anchoring points 56A, 56B respectively of the first and second stiffening elements 54A, 54B of each first and second primary group 601A, 601B are distributed circumferentially according to each first and second constant interior angular pitch A1A, A1B respectively. Thus, each angular distance between the two first and second end stiffening elements 541A, 542A and 541B, 542B of each first and second primary group 601A, 601B considered is respectively equal therefore (

[0180] Likewise, the first and second radially inner anchoring points 56A, 56B respectively of the first and second stiffening elements 54A, 54B of each first and second secondary group 602A, 602B are distributed circumferentially according to each first and second constant inner angular pitch A 1A, A1 B . Thus, each angular distance between the two first and second end stiffening elements 541 A, 542A and 541 B, 542B of each first and second secondary group 602A, 602B considered is respectively equal to (N2A- 1)*A1A and (N2B-1)*A1B. Here, N2A=N2B, A2A=A2B and therefore (N2A- 1)*A1 A=(N2B- 1 )*A 1 B.

[0181] A first internal angular pitch A2A separating on the one hand the first radially internal anchoring point 56A of each first end stiffening element 541A, 542A of one of the first groups 60A and on the other hand the first radially internal anchoring point 56A of the first end stiffening element 542A, 541 A of another first group 60A, which is adjacent to the first end stiffening element 541 A, 542A considered, is different from the first constant internal angular pitch A1A, here is strictly greater than the first constant internal angular pitch A1 A.Similarly, a second internal angular pitch A2B separating on the one hand the second radially internal anchoring point 56B of each second end stiffening element 541 B, 542B of one of the second groups 60B and on the other hand the second radially internal anchoring point 56B of the second end stiffening element 542B, 541 B of another second group 60B, which is adjacent to the second end stiffening element 541 B, 542B considered, is different from the second constant internal angular pitch A1 B, here is strictly greater than the second constant internal angular pitch A1 B.

[0182] More precisely, the first internal angular pitch A2A between the first end stiffening element 541A of a first primary group 601A and the first end stiffening element 542A of the first secondary group 602A adjacent to the first primary group 601A considered is strictly greater than the first constant internal angular pitch A1A. Similarly, the first internal angular pitch A2A between the first end stiffening element 542A of a first primary group 601A and the first end stiffening element 541A of the first secondary group 602A adjacent to the first primary group 601A considered is strictly greater than the first constant internal angular pitch

[0183] AIA.

[0184] Similarly, the second internal angular pitch A2B between the second end stiffening element 541B of a second primary group 601B and the second end stiffening element 542B of the second secondary group 602B adjacent to the second primary group 601B considered is strictly greater than the second constant internal angular pitch A1B. Similarly, the second internal angular pitch A2B between the second end stiffening element 542B of a second primary group 601B and the second end stiffening element 541B of the second secondary group 602B adjacent to the second primary group 601B considered is strictly greater than the second constant internal angular pitch

[0185] AI B .

[0186] The first and second radially outer anchoring points 58A, 58B of the first and second stiffening elements 54A, 54B of each first and second group 60A, 60B are distributed circumferentially according to first and second constant outer angular pitches A3A, A3B.

[0187] A first external angular pitch A4A separating on the one hand the first radially external anchoring point 58A of each first end stiffening element 541A, 542A of one of the first groups 60A and on the other hand the first radially external anchoring point 58A of the first end stiffening element 542A, 541A of another first group 60A, which is adjacent to the first end stiffening element 541A, 542A considered, is equal to the first constant external angular pitch A3A. Thus, all of the first radially external anchoring points 58A of the first stiffening elements 54A are distributed circumferentially according to the first constant external angular pitch A3A.

[0188] Similarly, a second external angular pitch A4B separating on the one hand the second radially external anchoring point 58B of each second end stiffening element 541 B, 542B of one of the second groups 60B and on the other hand the second radially external anchoring point 58B of the second end stiffening element 542B, 541 B of another second group 60B, which is adjacent to the second end stiffening element 541 B, 542B considered, is equal to the second constant external angular pitch A3B. Thus, all of the second radially external anchoring points 58B of the second stiffening elements 54B are distributed circumferentially according to the second constant external angular pitch A3B.

[0189] Each first and second constant exterior angular step A3A, A3B is here strictly greater than respectively each first constant interior angular step A1 A, A1 B.

[0190] Each first and second stiffening element 54A, 54B of each first and second group 60A, 60B extends in a main direction forming with the radial direction of the tire 10 an angle of inclination such that at least two first stiffening elements 54A of each first group 60A extend at different angles of inclination and such that at least two second stiffening elements 54B of each second group 60B extend at different angles of inclination.

[0191] Each first stiffening element 54A of each first group 60A extends in a main direction forming with the radial direction of the tire 10 an angle of inclination such that the angles of inclination are decreasing when moving circumferentially from the first end stiffening element 541A of each first group 60A towards a first intermediate stiffening element 543A of each first group 60A included between the two first end stiffening elements 541A, 542A of each first group 60A. Here, the first intermediate stiffening element 543A of each first group 60A is located at an angular equidistant from each first end stiffening element 541A, 542A.Each first stiffening element 54A of each first group 60A extends in a main direction forming with the radial direction of the tire 10 an angle of inclination such that the angles of inclination are increasing when moving circumferentially from the first intermediate stiffening element 543A towards the other first end stiffening element 542A of each first group 60A.

[0192] Similarly, each second stiffening element 54B of each second group 60B extends in a main direction forming with the radial direction of the tire 10 an angle of inclination such that the angles of inclination are decreasing when moving circumferentially from the second end stiffening element 541B of each second group 60B towards a second intermediate stiffening element 543B of each second group 60B included between the two second end stiffening elements 541B, 542B of each second group 60B. Here, the second intermediate stiffening element 543B of each second group 60B is located at an angular equidistant from each second end stiffening element 541B, 542B.Each second stiffening element 54B of each second group 60B extends in a main direction forming with the radial direction of the tire 10 an angle of inclination such that the angles of inclination are increasing when moving circumferentially from the second intermediate stiffening element 543B towards the other second end stiffening element 542B of each second group 60B.

[0193] The angle of inclination of each first and second intermediate stiffening element 543A, 543B is, in absolute value, less than or equal to 2° and here substantially zero. Each first and second end stiffening element 541A, 542A and 541B, 542B of each first and second group 60A, 60B extends in a main direction forming with the radial direction of the tire 10 an angle in absolute value ranging from 5° to 20°, more particularly ranging from 10° to 20°, and even more particularly ranging from 15° to 20°.

[0194] Figure 4 illustrates a tire of the prior art not in accordance with the invention and as described in WO2022 / 200717. This tire comprises first and second stiffening elements arranged so that all of the first and second radially inner anchoring points are distributed circumferentially according to a constant inner angular pitch and so that all of the first and second radially outer anchoring points are distributed circumferentially according to a constant outer angular pitch. In Figure 4, the roundness defects associated with a method, here that described in WO2022 / 200717, are schematized in an exaggerated manner by arcs of circles CD. For a given azimuth, the further the arc of circle CD is from the circle CR, the greater the actual radius of the tire compared to its theoretical radius at this azimuth.Conversely, the closer the arc of the circle CD is to the circle CR, the smaller the actual radius of the tire is compared to its theoretical radius at this azimuth. The theoretical radius is represented by the circle CT.

[0195] Figure 5 illustrates the tire according to the first embodiment described previously with reference to Figures 1 to 3. Thanks to the invention, the arcs have smaller amplitudes, which makes it possible to bring the actual radius of the tire closer to its theoretical radius for each azimuth and therefore to reduce roundness defects. This reduces the acoustic signature of the process.

[0196] The second exemplary embodiment illustrated in Figure 6 differs from the first exemplary embodiment in that the first external angular pitch A4A separating on the one hand the first radially external anchoring point 58A of each first end stiffening element 541A, 542A of one of the first group 60A and on the other hand the first radially external anchoring point 58A of the first end stiffening element 542A, 541A of another first group 60A, which is adjacent to the first end stiffening element 541A, 542A, is different from the first constant external angular pitch A3A, here is strictly greater than the first constant external angular pitch A3A.Similarly, the external angular pitch A4B separating on the one hand the second radially external anchoring point 58B of each second end stiffening element 541A, 542A of one of the second groups 60B and on the other hand the second radially external anchoring point 58B of the second end stiffening element 542B, 541B of another second group 60B, which is adjacent to the second end stiffening element 541B, 542B, is different from the second constant external angular pitch A3B, here is strictly greater than the second constant external angular pitch A3B.

[0197] The first internal angular pitch A2A separating on the one hand the first radially internal anchoring point 56A of each first end stiffening element 541A, 542A of one of the first groups 60A and on the other hand the first radially internal anchoring point 56A of the first end stiffening element 542A, 541A of another first group 60A, which is adjacent to the first end stiffening element 541A, 542A considered, is equal to the first constant internal angular pitch A1A. Thus, all of the first radially internal anchoring points 56A of the first stiffening elements 54A are distributed circumferentially according to the first constant internal angular pitch A1A.

[0198] Similarly, the second internal angular pitch A2B separating on the one hand the second radially internal anchoring point 56B of each second end stiffening element 541B, 542B of one of the second groups 60B and on the other hand the second radially internal anchoring point 56B of the second end stiffening element 542B, 541B of another second group 60B, which is adjacent to the second end stiffening element 541B, 542B considered, is equal to the second constant internal angular pitch A1B. Thus, all of the second radially internal anchoring points 56B of the second stiffening elements 54B are distributed circumferentially according to the second constant internal angular pitch A1B.

[0199] The third exemplary embodiment illustrated in Figure 7 is a combination of the first and second exemplary embodiments described previously.

[0200] Thus, each first and second interior angular step A2A, A2B is different respectively from each first and second constant interior angular step A1A, A1 B, here strictly greater respectively than each first and second constant interior angular step A1A, A1 B. Each first and second exterior angular step A4A, A4B is different respectively from each first and second constant exterior angular step A3A, A3B, here strictly greater respectively than each first and second constant exterior angular step A3A, A3B.

[0201] Unlike the first and second embodiments described previously, each first and second stiffening element 54A, 54B extends here in a main direction forming, with the radial direction of the tire 10, an angle in absolute value less than 2°, in particular a substantially zero angle.

[0202] Embodiments may be envisaged in which groups are made up of the two end stiffening elements and therefore do not include intermediate elements. The constant angular pitch of each of these groups is therefore the angle separating the relevant anchoring points of the two end stiffening elements.

[0203] We can consider a plurality of groups each having a constant angular pitch different from that of the other groups.

[0204] It may be envisaged to combine the characteristics of the invention described above with anchoring members such as described in application FR23 15326 and / or with a sealing layer such as described in application FR2315327 or the absence of a sealing layer such as described in FR2315327 and / or main and complementary stiffening elements such as described in FR23 15325 and / or inner and outer layers such as described in FR2315328 and / or with anchoring of the radially inner portion of the stiffening elements such as described in FR2401572 filed in the name of the applicant of the present application.

Claims

CLAIMS 1. A tire (10) comprising a crown (12), first and second sidewalls (30A, 30B) each extending the crown (12) radially inward, first and second beads (32A, 32B) respectively extending the first and second sidewalls (30A, 30B) radially inward, the tire (10) being provided with an internal surface (34) delimiting a toric cavity (36) for inflating the tire (10), the tire (10) comprising a stiffening structure (52) comprising a plurality of first stiffening elements (54A) each extending continuously in the toric cavity (36) from at least the first sidewall (30A) and / or bead (32A) from a first radially internal anchoring point (56A) to at least the crown (12),characterized in that: the first stiffening elements (54A) are arranged in first groups (60A) of first stiffening elements (54A) adjacent to each other in the circumferential direction of the tire (10); each first group (60A) is circumferentially delimited by two first end stiffening elements (541A, 542A); the first radially inner anchoring points (56A) of the first stiffening elements (54A) of each first group (60A) are distributed circumferentially according to a first constant inner angular pitch (A 1A); and the first inner angular pitch (A2A) separating on the one hand the first radially inner anchoring point (56A) of each first end stiffening element (541A, 542A) of one of the first groups (60A) and on the other hand the first radially inner anchoring point (56A) of the first end stiffening element (541A,542A) of another first group (60A), which is adjacent to said first end stiffening element (541 A, 542A), is different from the first constant internal angular pitch (A1A)., 2. A tire (10) comprising a crown (12), first and second sidewalls (30A, 30B) each extending the crown (12) radially inward, first and second beads (32A, 32B) respectively extending the first and second sidewalls (30A, 30B) radially inward, the tire (10) being provided with an internal surface (34) delimiting a toric cavity (36) for inflating the tire (10), the tire (10) comprising a stiffening structure (52) comprising a plurality of first stiffening elements (54A) each extending continuously in the toric cavity (36) from at least the first sidewall (30A) and / or bead (32A) to at least the crown (12) to a first radially outer anchoring point (58A),characterized in that: the first stiffening elements (54A) are arranged in first groups (60A) of first stiffening elements (54A) adjacent to each other in the circumferential direction of the tire (10); each first group (60A) is circumferentially delimited by two first end stiffening elements (541A, 542A); the first radially outer anchoring points (58A) of the first stiffening elements (54A) of each first group (60A) are distributed circumferentially according to a first constant outer angular pitch (A3A); and the first outer angular pitch (A4A) separating on the one hand the first radially outer anchoring point (58A) of each first end stiffening element (541A, 542A) of one of the first groups (60A) and on the other hand the first radially outer anchoring point (58A) of the first end stiffening element (541A,542A) of another first group (60A), which is adjacent to said first end stiffening element (541 A, 542A), is different from the first constant outer angular pitch (A3A)., 3. A tire (10) according to claim 1 or 2, wherein the stiffening structure (52) comprises a plurality of second stiffening elements (54B) each extending continuously in the toric cavity (36) from at least the second sidewall (30B) and / or bead (32B) from a second radially inner anchoring point (56B) to at least the crown (12), tire (10) in which: the second stiffening elements (54B) are arranged in second groups (60B) of second stiffening elements (54B) adjacent to each other in the circumferential direction of the tire (10); each second group (60B) is circumferentially delimited by two second end stiffening elements; the second radially inner anchoring points (56B) of the second stiffening elements (54B) of each second group (60B) are distributed circumferentially according to a second constant inner angular pitch (A1 B);and the second internal angular pitch (A2B) separating on the one hand the second radially internal anchoring point (56B) of each second end stiffening element (541B, 542B) of one of the second groups (60B) and on the other hand the second radially internal anchoring point (56B) of the second end stiffening element (541B, 542B) of another second group (60B), which is adjacent to said second end stiffening element (541B, 542B), is different from the second constant internal angular pitch (A1B).; 4. A tire (10) according to claim 1 or 2, wherein the stiffening structure (52) comprises a plurality of second stiffening elements (54B) each extending continuously in the toric cavity (36) from at least the second sidewall (30B) and / or bead (32B) to at least the crown (12) to a second radially outer anchoring point (58B), a tire (10) in which: the second stiffening elements (54B) are arranged in second groups (60B) of second stiffening elements (54B) adjacent to each other in the circumferential direction of the tire (10); each second group (60B) is circumferentially delimited by two second end stiffening elements (541 B, 542B); the second radially outer anchoring points (58B) of the second stiffening elements (54B) of each second group (60B) are distributed circumferentially according to a second constant outer angular pitch (A3A); and the second outer angular pitch (A4A) separating on the one hand the second radially outer anchoring point (58B) of each second end stiffening element (541B, 542B) of one of the second groups (60B) and on the other hand the second radially outer anchoring point (58B) of the second end stiffening element (541B, 542B) of another second group (60B), which is adjacent to said second end stiffening element (541B, 542B), is different from the second constant outer angular pitch (A3A).

5. Tire (10) according to any one of the preceding claims, in which each first stiffening element (54A) of said first group (60A) extends in a main direction forming with the radial direction of the tire (10) an angle of inclination such that at least two first stiffening elements (54A) of said first group (60A) extend at different angles of inclination.

6. Tire (10) according to any one of the preceding claims, in which each first stiffening element (54A) of said first group (60A) extends in a main direction forming with the radial direction of the tire (10) an angle of inclination such that: - the angles of inclination are decreasing when moving circumferentially from one of the two first end stiffening elements (541A, 542A) of said first group (60A) towards a first intermediate stiffening element (543A) of said first group (60A) between the two first end stiffening elements (541A, 542A) of said first group (60A), - the angles of inclination are increasing when moving circumferentially from a first intermediate stiffening element (543A) comprised between the two first end stiffening elements (541 A, 542A) of said first group (60A) towards the other of the two first end stiffening elements (541A, 542A) of said first group (60A).

7. Tire (10) according to any one of the preceding claims, in which each first stiffening element (54A) is anchored in the crown (12) from a first radially outer anchoring point (58A), the first radially outer anchoring points (58A) of the first stiffening elements (54A) of each first group (60A) being distributed circumferentially according to a first constant outer angular pitch (A3A).

8. A tire (10) according to claim 1 or any one of claims 3 to 7 which depends on claim 1, wherein all of the first radially outer anchoring points (58A) of the first stiffening elements (54A) are distributed circumferentially according to a first constant outer angular pitch (A3A).

9. Tire (10) according to any one of the preceding claims, in which each first stiffening element (54A) is anchored in the first sidewall (30A) and / or bead (32A) from a first radially inner anchoring point (56A), the first radially inner anchoring points (56A) of the first stiffening elements (54A) of each first group (60A) being distributed circumferentially according to a first constant inner angular pitch (A1A).

10. A tire (10) according to claim 2 or according to any one of claims 3 to 7 which depends on claim 2 or according to claim 9 which depends on claim 2, in which all of the first radially inner anchoring points (56A) of the first stiffening elements (54A) are distributed circumferentially according to a first constant inner angular pitch (A1A). 1 1. Tire (10) according to any one of the preceding claims, in which each first stiffening element (54A) of said first group (60A) extends in a main direction forming with the radial direction of the tire (10) an angle of inclination such that the angle of inclination of at least one first intermediate stiffening element (543A) between the first end stiffening elements (541 A, 542A) of said first group (60A) is, in absolute value less than or equal to 2°, preferably substantially zero.

12. Tire (10) according to any one of the preceding claims, in which the two first end stiffening elements (541A, 542A) of each first group (60A) extend in a main direction forming, with the radial direction of the tire (10), an angle in absolute value ranging from 5° to 20°, in particular ranging from 10° to 20°, more particularly ranging from 15° to 20°.

13. Tire (10) according to any one of the preceding claims, in which the first groups (60A) comprise at least one first primary group (601 A) and at least one first secondary group (602A), the or each first primary group (601 A) comprising a number of first stiffening elements (54A) strictly greater than the number of first stiffening elements (54A) of the or each first secondary group (602A).

14. Tire (10) according to the preceding claim, in which the first groups (60A) comprise several first primary and secondary groups (601A, 602A) arranged alternately in the circumferential direction of the tire (10).

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