CA3203673A1

CA3203673A1 - Tyre comprising a bracing ply having a hydrophobic weft and a reduced crown thickness

Info

Publication number: CA3203673A1
Application number: CA3203673A
Authority: CA
Inventors: Arnaud Delbast; Laure GALLARD; Pascal BONNAMAIN
Original assignee: Compagnie Generale des Etablissements Michelin SCA
Current assignee: Compagnie Generale des Etablissements Michelin SCA
Priority date: 2021-01-07
Filing date: 2022-01-03
Publication date: 2022-07-14
Also published as: CN116710293A; EP4274746A1; JP2024503639A; FR3118605B1; WO2022148921A1; KR20230129060A; FR3118605A1

Abstract

The tyre (10) comprises a crown reinforcement (16) comprising a working reinforcement (20) that includes a radially outermost working ply (26) and a bracing reinforcement (22) comprising a plurality of filamentary textile bracing elements (220) wound radially in a helix around the working reinforcement (20) and linked to one another by one or more filamentary weft element(s) (42). In the axially central portion (PO) of the crown (12), the mean radial distance E1 between the base of the tread groove and the filamentary textile bracing elements (220) is such that E1 ? 2.00 mm. Each filamentary weft element (42) comprises multiple textile monofilaments and/or multiple textile fibres selected from among the synthetic organic polymer monofilaments and fibres, the synthetic inorganic polymer monofilaments and fibres and the assemblies of these monofilaments and fibres.

Description

Tyre comprising a bracing ply having a hydrophobic weft and a reduced crown thickness [001] The present invention relates to a tyre. A tyre means a casing intended to form a cavity by cooperating with a support element, for example a rim, this cavity being able to be pressurized to a pressure higher than atmospheric pressure. A tyre according to the invention has a structure of substantially toroidal shape exhibiting symmetry of revolution about a main axis of the tyre.

[002] Tyres for passenger vehicles comprising a crown comprising a tread and also a crown reinforcement are known from the prior art. The crown reinforcement conventionally comprises a hoop reinforcement and a working reinforcement. The hoop reinforcement is arranged radially outside the working reinforcement and radially inside the tread.

[003] The working reinforcement comprises a radially inner working layer and a radially outer working layer arranged radially outside the radially inner working layer. Each radially inner and outer working layer is axially delimited by two axial edges of said working layer and comprises metal filamentary working reinforcing elements extending axially from one axial edge to the other axial edge of said working layer, substantially parallel to one another.

[004] The hoop reinforcement is axially delimited by two axial edges and comprises a strip helically wound over a plurality of circumferential turns so as to extend axially between the axial edges of the hoop reinforcement. The strip comprises a plurality of textile filamentary hooping reinforcing elements that are substantially parallel to one another and extend in a main hooping direction.

[005] Firstly, it has been observed that, despite their excellent performance, after running under extremely harsh conditions and in the presence of corrosive agents, these tyres exhibited pockets of oxidation on the working reinforcement, in particular on the radially outer working layer. Such extremely harsh conditions are in particular encountered when running the tyres on stony road surfaces. While the oxidation pockets do not threaten safe use, they may generate vibrations for the driver of the vehicle, representing a source of discomfort that it is desirable to eliminate.

[006] Secondly, in order to reduce the weight of tyres and also the rolling resistance thereof as well as the environmental impact thereof, it is sought to reduce the amount of materials used, in particular in the crown of tyres. Nevertheless, by reducing the amounts of materials used in the crown, this predictably means that the hoop reinforcement and the working reinforcement will be exposed to increased penetration by corrosive agents and thus to quicker and greater formation of the previously described oxidation pockets. Thus, lighter tyres would indeed be obtained, but accompanied with amplified vibratory discomfort, which is undesirable.

[007] The aim of the invention is to obtain a tyre having an improved compromise between the vibratory discomfort generated by oxidation pockets and the weight of the tyre and consequently the rolling resistance thereof.

[008] To this end, the subject of the invention is a tyre comprising a crown comprising a tread bearing a tread surface, the crown comprising an axially central portion extending over an axial width equal to 50% of the axial width of the tread surface and axially centred over the mid-plane of the tyre, the axially central portion of the tread comprising at least one deepest cut of the axially central portion of the tread, the crown comprising a crown reinforcement comprising:
- a working reinforcement comprising at least one radially outermost working layer of the working reinforcement, the radially outermost working layer comprising metal filamentary working reinforcing elements, - a hoop reinforcement comprising a plurality of textile filamentary hooping reinforcing elements helically wound radially around the working reinforcement and connected to one another by one or more filamentary weft element(s), the hoop reinforcement being arranged radially outside the working reinforcement and radially inside the tread, in which tyre, in the axially central portion of the crown, the mean radial distance El between:
- the surface that passes through the radially innermost point of the or each deepest cut of the axially central portion of the tread and substantially parallel to the tread surface and - the radially outer surface that passes through the radially outermost points of the textile filamentary hooping reinforcing elements that are radially outermost among the textile filamentary hooping reinforcing elements, is such that El 2.00 mm, and in which tyre the or at least one of the filamentary weft element(s) comprises a plurality of textile monofilaments and/or a plurality of textile fibres selected from organic polymeric synthetic fibres and monofilaments, inorganic polymeric synthetic fibres and monofilaments, and assemblies of these monofilaments and fibres.

[009] In order to achieve the aim of the invention, the inventors of this invention have had to demonstrate the mechanism leading to the formation of oxidation pockets.
Thus, the inventors observed that the extremely harsh conditions encountered when running the tyre on stony road surfaces are such that the stones covering the road surface form indents that attack the tyre tread, going so far as to perforate the tread and reach the crown reinforcement. Once the tread has been subject to these attacks, corrosive agents, in particular water and salt firstly penetrate into the crown reinforcement via the hoop reinforcement. Within the hoop reinforcement of tyres of the prior art, it was observed that, secondly, corrosive agents were conducted into the hoop reinforcement not via the textile filamentary hooping reinforcing elements but rather by the filamentary weft elements that connect the textile filamentary hooping reinforcing elements to one another.
This conduction of the corrosive agents is made possible by the very nature of the filamentary weft elements which comprise an assembly comprising cotton monofilaments. Until the inventors' discovery, the use of cotton was driven solely by the relatively low cost of cotton and by the fact that such filamentary weft elements were only useful during the process for manufacturing the hoop reinforcement described below and had no effect on the formation of the oxidation pockets.

[010] Indeed, in the tyres of the prior art, such filamentary weft elements are substantially parallel to one another in a main weft direction that is not colinear with the main hooping direction. The main weft direction and the main hooping direction are substantially perpendicular. Such filamentary weft elements are used in the process for manufacturing the strip, during which, in a step of manufacturing a very wide fabric, the textile filamentary hooping reinforcing elements are arranged substantially parallel to one another and are connected to one another by one or more filamentary weft elements, each filamentary weft element extending over the whole width of the very wide fabric. In a subsequent sizing step, the textile filamentary hooping reinforcing elements and the filamentary weft elements are coated with one or more layers of one or more adhesive compositions, then the very wide fabric obtained beforehand is heat treated so as to obtain a sized very wide fabric. Then, in a subsequent calendering step, the sized very wide fabric is embedded in an elastomer matrix so as to obtain a calendered very wide fabric. Subsequently, in a cutting step, the calendered very wide fabric is cut up so as to obtain a plurality of narrow strips in which the textile filamentary hooping reinforcing elements extend in a direction substantially parallel to the direction of the greatest length of the strip.

[011] Thus, as explained above, until the inventors' discovery, it was believed that the sole function of the filamentary weft elements was to hold the textile filamentary hooping reinforcing elements relative to one another during the various steps of sizing, calendering and cutting.

[012] Once the critical role of the filamentary weft elements in the formation of oxidation pockets in the tyres of the prior art was discovered, the inventors thus proposed eliminating the conduction means formed by the cotton filamentary weft elements and, in accordance with the invention, identified that filamentary weft element(s) comprising as few monofilaments as possible and as few fibres that conduct corrosive agents as possible made it possible to limit the formation of oxidation pockets. Thus, the invention teaches the use of organic and/or inorganic synthetic fibres and/or monofilaments which, by their very nature, do not conduct any, or only very little, water or corrosive agents; in any case, far less than cotton.

[013] Indeed, the organic and/or inorganic synthetic fibres and/or monofilaments have a relatively low moisture regain. Thus, the or at least one filamentary weft element(s) has a moisture regain typically of strictly less than 5.0%, preferably less than or equal to 3.0%, and even more preferentially less than or equal to 2.0%. The moisture regain is measured in accordance with standard ASTM D 885/D 885MA, January 2010 (paragraph 10) and is defined as the ratio of the weight of water contained in the filamentary weft element to the dry weight of the filamentary weft element, expressed as a percentage, and is equal to [(W - M)/M] x 100 , where W is the weight in grams of the filamentary weft element, subjected to a temperature of 23 C 2 C under 50% 10% relative humidity for 48 h, according to standard IS023529:2016, and M is the weight in grams of the filamentary weft element after drying in an oven.

[014] In accordance with the invention, the textile filamentary hooping reinforcing elements are connected to one another by one or more filamentary weft element(s). Thus, the filamentary weft element(s) are interwoven with the textile filamentary hooping reinforcing elements, in contact with the textile filamentary hooping reinforcing elements, so as to hold each textile filamentary hooping reinforcing element at a given distance from the textile filamentary hooping reinforcing element adjacent thereto. The interweaving of the textile filamentary hooping reinforcing elements and of the filamentary weft element(s) defines a weave. A well-known weave is the taffeta weave, also referred to as plain weave.

[015] Textile fibres and monofilaments are usually classified in two main categories:
natural fibres and monofilaments and chemical fibres and monofilaments.
Natural fibres and monofilaments include monofilaments and fibres of plant origin (in particular including cotton), of animal origin and of mineral origin. Chemical fibres and monofilaments include artificial fibres and monofilaments and synthetic fibres and monofilaments.
Artificial fibres and monofilaments are produced from natural raw materials and include in particular viscose, produced from wood cellulose. Synthetic fibres and monofilaments include organic polymeric fibres and monofilaments (for example polyesters and polyamides) and also inorganic polymeric fibres and monofilaments (for example glass and carbon).

[016] Thus, in accordance with the invention, the presence of natural monofilaments and natural fibres, and also the presence of artificial monofilaments and artificial fibres, will be avoided as much as possible, and preferably entirely.

[017] Each filamentary hooping reinforcing element is textile in the sense that it comprises, for at least 50% of the weight thereof, one or more textile monofilaments and/or one or more textile fibres, and preferably consists of one or more textile monofilaments and/or one or more textile fibres.

[018] A monofilament is a very long, continuous, single filamentary element, generally obtained by spinning from a molten material. A fibre is a short single filamentary element. A
plurality of fibres are spun together to obtain a continuous thread. Thus, the in case in which the assembly comprises polymeric synthetic fibres alone or in combination with polymeric synthetic monofilaments, the assembly comprises one or more continuous thread(s), each continuous thread being formed by a spun yarn (or assembly) of these polymeric synthetic fibres.

[019] In order to improve the compromise between the vibratory discomfort caused by the oxidation pockets and the weight of the tyre and therefore the rolling resistance thereof, the invention proposes making use of the filamentary weft element(s) that do not conduct corrosive agents, or only conduct them a little, to reduce the thickness of the material(s) separating the bottom of the deepest cut of the axially central portion of the tread and the textile filamentary hooping reinforcing elements of the axially central portion of the tread.
This thickness is represented by the mean radial distance El. Thus, although the risk of having corrosive agents reach the hoop reinforcement is increased by reducing the mean radial distance El, the act of preventing the conduction of the corrosive agents by the filamentary weft element(s) makes it possible to not increase, or even to decrease, the total surface area of the oxidation pockets.

[020] Thus, in a first improved compromise compared to the prior art, it is possible to choose to greatly reduce the mean radial distance El. An increase in the total surface area of the oxidation pockets will thus be prevented; the surface area will not necessarily be reduced, but the tyre will be significantly lightened and thus the rolling resistance thereof will be reduced. In a second improved compromise compared to the prior art, it is possible to choose to moderately reduce the mean radial distance El. The total surface area of the oxidation pockets will thus be reduced, and the tyre will be moderately lightened and the rolling resistance thereof will be moderately reduced. Which compromise to choose will be decided by those skilled in the art according to the intended use of the tyre.

[021] The mean radial distance El is determined on the axially central portion of the crown by measuring, between the surfaces, a plurality of radial distances that are axially distributed over the width of the axially central portion of the crown. A
distance will be measured, for example, every centimetre in the axial direction starting from an end plane that axially delimits the axially central portion of the crown. Of course, if the radially outermost point of the radially outermost textile filamentary hooping reinforcing element of the textile filamentary hooping reinforcing elements is radially outside the surface that passes through the radially innermost point of the or each deepest cut of the axially central portion of the tread and substantially parallel to the tread surface, the radial distance measured is considered to be negative in order to take into account the greater likelihood of the effect of corrosive agents. Conversely, and in the vast majority of cases, if the radially outermost point of the radially outermost textile filamentary hooping reinforcing element of the textile filamentary hooping reinforcing elements is radially inside the surface that passes through the radially innermost point of the or each deepest cut of the axially central portion of the tread and substantially parallel to the tread surface, the radial distance measured is considered to be positive.

[022] These measurements will be taken in several meridian sectional planes, distributed equidistantly over the circumference of the tyre, for example in four meridian sectional planes. The mean of the radial distances thus measured will then be calculated in order to obtain the mean radial distance El.

[023] Radial distance between two surfaces means the straight-line distance between a point on one of the surfaces and the projection thereof on the other of the surfaces, in the radial direction of the tyre.

[024] The axially central portion of the tread is the axial portion of the tread of the axially central portion of the crown. These axially central portions of the crown and of the tread are axially delimited by the same first and second end planes, each first and second end plane being perpendicular to the axial direction of the tyre and passing through first and second points located axially at an axial distance from the mid-plane of the tyre equal to 25% of the width of the tread surface.

[025] Conventionally, the tread surface is determined on a tyre mounted on a measuring rim and inflated to nominal pressure (250 kPa or 290kPa, depending on whether it is a standard or reinforced tyre) according to the European Tyre and Rim Technical Organisation (ETRTO) 2020 standards manual. If there is an obvious boundary between the tread surface and the rest of the tyre, the axial width of the tread surface is simply measured. If the tread surface is continuous with the outer surfaces of the sidewalls of the tyre, the axial limit of the tread surface passes through the point at which the angle between the tangent to the tread surface and a straight line parallel to the axial direction passing through this point is equal to 30 . When, in a meridian sectional plane, there are several points for which said angle is equal, in terms of absolute value, to 30 , the radially outermost point is adopted.

[026] Optionally and preferentially, the tyre according to the invention is for a vehicle selected from passenger vehicles, light utility vehicles and camper vans, and even more preferentially the tyre according to the invention is for a passenger vehicle.

[027] A tyre for a passenger vehicle is a passenger-vehicle tyre or a tyre for a car, as defined in the manual of the ETRTO 2020 standard. Such a tyre has a section in a meridian sectional plane that is characterized by a section height H and a nominal section width SW, according to the manual of the ETRTO 2020 standard. More preferably and optionally, the passenger vehicle tyres to which the invention will advantageously be applied are such that the ratio H/S, expressed as a percentage, is at most equal to 90, preferably at most equal to 80 and more preferentially at most equal to 70, and is at least equal to 20, preferably at least equal to 80 and more preferentially at least equal to 30, and the nominal section width SW is at least equal to 115 mm, preferably at least equal to 155 mm and more preferentially at least equal to 175 mm and at most equal to 385 mm, preferably at most equal to 315 mm, more preferentially at most equal to 285 mm. In addition, the rim flange diameter D, defining the diameter of the tyre mounting rim, is at least equal to 12 inches, preferably at least equal to 16 inches and at most equal to 24 inches, preferably at most equal to 21 inches. The nominal section width SW, the nominal aspect ratio H/S and the rim flange diameter D are those indicated by the size marking inscribed on the sidewall of the tyre and in accordance with the manual of the ETRTO 2020 standard.

[028] A tyre for a light utility vehicle or camper van is as defined in the manual of the ETRTO 2020 standard, sections 10 to 12 of the part relating to tyres for utility vehicles.

[029] On a new tyre, the depth of a cut is the maximum radial distance between the bottom of the cut and its projection onto the ground when the tyre is running. The maximum value for the depths of the cuts is referred to as the tread pattern height. In most tyres, the deepest cut of the axially central portion of the tread is also the deepest cut of the tread, and thus defines the tread pattern height.

[030] A cut denotes either a groove or a sipe, and forms a space opening onto the tread surface.

[031] A sipe or a groove has, on the tread surface, two main characteristic dimensions: a width and a curvilinear length which are such that the curvilinear length is at least equal to two times the width. A sipe or a groove is therefore delimited by at least two main lateral faces determining its curvilinear length and connected by a bottom face, the two main lateral faces being distant from one another by a non-zero distance referred to as the width of the cut.

[032] On a new tyre, the width of a cut is the maximum distance between the two main lateral faces measured, when the cut is not chamfered, at a radial side coincident with the tread surface and, when the cut is chamfered, at the radially outermost radial side of the cut and radially inside the chamfer. The width is measured substantially perpendicularly to the main lateral faces.

[033] The axial width of a cut is measured in the axial direction of the tyre, for example in a meridian sectional plane of the tyre.

[034] A sipe is such that the distance between the main lateral faces is suitable for enabling the main lateral faces that delimit said sipe to come into at least partial contact in the contact patch, particularly when the tyre is new and under normal running conditions, particularly including the fact that the tyre is under nominal load and at nominal pressure.

[035] A groove is such that the distance between the main lateral faces is such that these main lateral faces cannot come into contact with one another under normal running conditions, particularly including the fact that the tyre is under nominal load and at nominal pressure.

[036] A cut may be transverse or circumferential.

[037] A transverse cut is such that the cut extends in a mean direction that makes an angle strictly greater than 300, preferably greater than or equal to 450 with the circumferential direction of the tyre. The mean direction is the shortest curve that joins the two ends of the cut and is parallel to the tread surface. A transverse cut may be continuous, which is to say not interrupted by a tread pattern block or another cut, such that the two main lateral faces that determine its length are uninterrupted over the length of the transverse cut. A transverse cut may equally be discontinuous, which is to say interrupted by one or more tread pattern blocks and/or one or more other cuts, such that the two main lateral faces that determine its length are interrupted by one or more tread pattern blocks and/or one or more other cuts.

[038] A circumferential cut is such that the cut extends in a mean direction that makes an angle less than or equal to 30 , preferably less than or equal to 100 with the circumferential direction of the tyre. The mean direction is the shortest curve that joins the two ends of the cut and is parallel to the tread surface. In the case of a circumferential cut that is continuous, the two ends coincide with one another and are joined by a curve that makes a full circuit of the tyre. A circumferential cut may be continuous, which is to say not interrupted by a tread pattern block or another cut, such that the two main lateral faces that determine its length are uninterrupted over a full circuit of the tyre. A circumferential cut may equally be discontinuous, which is to say interrupted by one or more tread pattern blocks and/or one or more other cuts, such that the two main lateral faces that determine its length are interrupted by one or more tread pattern blocks and/or one or more other cuts over a full circuit of the tyre.

[039] In the case of a circumferential cut that is situated outside of the mid-plane of the tyre, the lateral faces are referred to as axially inner face and axially outer face, the axially inner face being arranged, at a given azimuth, axially on the inside of the axially inner face in relation to the mid-plane.

[040] Each circumferential cut comprises axially inner and outer axial ends.
Irrespective of whether a circumferential cut has a chamfer or not, each axially inner and outer end is located respectively on each axially inner or outer edge.

[041] In the case of a transverse cut, the lateral faces are referred to as leading face and trailing face, the leading face being that of which the edge, for a given circumferential line, enters the contact patch before the edge of the trailing face.

[042] In some embodiments, the or each circumferential cut, whether it is a main circumferential cut or not, is chamfered. A chamfer on a circumferential cut may be a straight chamfer or rounded chamfer. A straight chamfer is formed by a planar face that is inclined with respect to the axially inner and outer face that it extends as far as the axially inner or outer edge axially delimiting the circumferential cut. A rounded chamfer is formed by a curved face that merges tangentially into the axially inner or outer face that it extends. A
chamfer on a circumferential cut is characterized by a height and a width which are respectively equal to the radial distance and to the axial distance between the point common to the axially inner or outer face extended by the chamfer and the axially inner or outer edge that axially delimits the circumferential cut.

[043] In some embodiments, the or each transverse cut is chamfered. In other words, each transverse cut is radially delimited by leading and trailing faces that circumferentially delimit said transverse cut and are connected to one another by a bottom face that delimits said transverse cut radially inwardly. A chamfer on a transverse cut may be a straight chamfer or rounded chamfer. A straight chamfer is formed by a planar face that is inclined with respect to the leading or trailing face that it extends as far as the leading or trailing edge circumferentially delimiting the transverse cut. A rounded chamfer is formed by a curved face that merges tangentially into the leading or trailing face that it extends. A chamfer on a transverse cut is characterized by a height and a width which are respectively equal to the radial distance and to the distance in a direction perpendicular to the leading or trailing faces between the point common to the leading or trailing face extended by the chamfer and the leading or trailing edge that circumferentially delimit the transverse cut.

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

[045] The axial direction is understood to be the direction substantially parallel to the axis of revolution of the tyre or of the mounted assembly, that is to say the axis of rotation of the tyre or of the mounted assembly.

[046] The circumferential direction is understood to be the direction that is substantially perpendicular both to the axial direction and to a radius of the tyre or of the mounted assembly (in other words, tangent to a circle centred on the axis of rotation of the tyre or of the mounted assembly).

[047] The radial direction is understood to be the direction along a radius of the tyre or of the mounted assembly, that is to say any direction that intersects the axis of rotation of the tyre or of the mounted assembly and is substantially perpendicular to that axis.

[048] Mid-plane of the tyre (denoted M) is understood to be the plane perpendicular to the axis of rotation of the tyre, which is situated axially halfway between the two beads and passes through the axial middle of the crown.

[049] The equatorial circumferential plane of the tyre is understood to be, in a meridian sectional plane, the plane passing through the equator of the tyre, perpendicular to the mid-plane and to the radial direction. The equator of the tyre is, in a meridian sectional plane (plane perpendicular to the circumferential direction and parallel to the radial and axial directions), the axis that is parallel to the axis of rotation of the tyre and situated equidistantly between the radially outermost point of the tread that is intended to be in contact with the ground and the radially innermost point of the tyre that is intended to be in contact with a support, for example a rim.

[050] The meridian plane is understood to be a plane which is parallel to and contains the axis of rotation of the tyre or of the mounted assembly and is perpendicular to the circumferential direction.

[051] Radially inner and radially outer are understood to mean closer to the axis of rotation of the tyre and further away from the axis of rotation of the tyre, respectively. Axially inner and axially outer are understood to mean closer to the mid-plane of the tyre and further away from the mid-plane of the tyre, respectively.

[052] A bead is understood to be the portion of the tyre intended to allow the tyre to be attached to a mounting support, for example a wheel comprising a rim. Each bead is thus in particular intended to be in contact with a flange of the rim, allowing it to be attached.

[053] Carcass or working layer is understood to be a layer comprising filamentary reinforcing elements which are continuous from one edge of the carcass or working layer to the other. Thus, a carcass or working layer can be turned over in the tyre so as to form a double thickness of said carcass or working layer. Two different carcass or working layers comprise filamentary reinforcing elements which are discontinuous from one layer to the other. Two superposed carcass or working layers form a thickness equal to the sum of the thicknesses of the two carcass or working layers.

[054] Any range of values denoted by the expression "between a and b"
represents the range of values extending from more than a to less than b (that is to say excluding the end-points a and b), whereas any range of values denoted by the expression "from a to b" means the range of values extending from a up to b (that is to say including the strict end-points a and b).

[055] The characteristics of the textile filamentary hooping reinforcing elements and also of the filamentary weft element(s) can be determined by extracting these elements from the tyre, for example according to a process in accordance with standard ASTM

-10a ¨ paragraph 6.4.

[056] Unless explicitly stated otherwise, the geometric characteristics of the tyre are taken on an unladen and non-inflated tyre or on a section of a tyre in a mid-plane, when this is possible.

[057] Optionally and preferentially, at least 50%, preferably at least 75% and even more preferentially 100% of the weight of the or each filamentary weft element consists of textile monofilaments and/or textile fibres selected from organic polymeric synthetic fibres and monofilaments, inorganic polymeric synthetic fibres and monofilaments, and assemblies of these monofilaments and fibres. In other words, when 100% of the weight of the or each filamentary weft element consists of textile monofilaments and/or textile fibres selected from organic polymeric synthetic fibres and monofilaments, inorganic polymeric synthetic fibres and monofilaments, and assemblies of these monofilaments and fibres, the or each filamentary weft element consists of textile monofilaments and/or textile fibres selected from organic polymeric synthetic fibres and monofilaments, inorganic polymeric synthetic fibres and monofilaments, and assemblies of these monofilaments and fibres. In this case, the or each filamentary weft element is free of natural monofilaments, natural fibres, artificial monofilaments and artificial fibres.

[058] By maximizing the proportion by weight of monofilaments and/or fibres that do not conduct corrosive agents in the or each filamentary weft element, the risk of conducting the corrosive agents is reduced.

[059] The proportion by weight of the monofilaments and fibres in question is determined by measuring the weight of the filamentary weft element then by separating the monofilaments and fibres in question and measuring the weight thereof. The ratio of the two weights is equal to the proportion by weight sought.

[060] Optionally and advantageously, at least 50%, preferably at least 75% and even more preferentially 100% of the cumulative length of the filamentary weft element(s) comprises a plurality of textile monofilaments and/or textile fibres selected from organic polymeric synthetic fibres and monofilaments, inorganic polymeric synthetic textile fibres and monofilaments, and assemblies of these monofilaments and fibres. By maximizing the length of filamentary weft elements that do not conduct corrosive agents, the risk of conducting the corrosive agents is reduced.

[061] The proportion of the cumulative length of the filamentary weft element(s) in question is determined over a representative portion of the tyre and if necessary over the whole tyre by measuring the cumulative length of the filamentary weft element(s) and by measuring the cumulative length of the filamentary weft element(s) in question. The ratio of the two cumulative lengths is equal to the proportion of the cumulative length sought.

[062] In optional embodiments which make it possible to maximize lightening of the tyre, El 1.80 mm, preferably El 1.50 mm, more preferentially El 1.40 mm and even more preferentially El 1.20 mm.

[063] Optionally, El 0.20 mm, preferably El 0.50 mm and more preferentially El 1.00 mm. The presence of a non-zero material thickness makes it possible to protect the textile filamentary hooping reinforcing elements from too many attacks and too great a penetration of the corrosive agents into the crown reinforcement.

[064] Optionally and advantageously, the or at least one of the filamentary weft element(s) comprises a plurality of organic polymeric synthetic textile fibres and/or monofilaments.
Such monofilaments and fibres are particularly inexpensive.

[065] Optionally and preferentially, at least 50%, preferably at least 75% and even more preferentially 100% of the weight of the or each filamentary weft element consists of textile monofilaments and/or textile fibres selected from organic polymeric synthetic fibres and monofilaments. In other words, when 100% of the weight of the or each filamentary weft element consists of textile monofilaments and/or textile fibres selected from organic polymeric synthetic fibres and monofilaments, the or each filamentary weft element consists of textile monofilaments and/or textile fibres selected from organic polymeric synthetic fibres and monofilaments. In this case, the or each filamentary weft element is free of natural monofilaments, natural fibres, artificial monofilaments and artificial fibres.
The proportion by weight is determined as described previously.

[066] Optionally and advantageously, at least 50%, preferably at least 75%, and even more preferentially 100%, of the cumulative length of the filamentary weft element(s) comprises a plurality of organic polymeric synthetic fibres and/or monofilaments. The proportion of the cumulative length is determined as described previously.

[067] In one optional and advantageous embodiment, the organic polymeric synthetic fibres and monofilaments are selected from polyester fibres and monofilaments, polyamide fibres and monofilaments, polyketone fibres and monofilaments, polyurethane fibres and monofilaments, acrylic fibres and monofilaments, polyolefin fibres and monofilaments, polyether ether ketone fibres and monofilaments and assemblies of these monofilaments and of these fibres, preferably from polyester fibres and monofilaments, polyamide fibres and monofilaments and assemblies of these monofilaments and of these fibres, and more preferentially the organic synthetic fibres and monofilaments are polyester fibres and monofilaments. Among the polyesters, PET (poly(ethylene terephthalate)), PEN
(poly(ethylene naphthalate)) and PEF (polyethylene-2,5-furandicarboxylate) will preferentially be chosen, and more particularly PET. Among the polyamides, aliphatic polyamides and aromatic polyamides will preferentially be chosen, and more particularly aliphatic polyamides.

[068] In some optional and preferred embodiments, in the axially central portion of the crown, the mean radial distance E2 between:

- the radially inner surface that passes through the radially innermost points of the textile filamentary hooping reinforcing elements that are radially innermost among the textile filamentary hooping reinforcing elements, - the radially outer surface that passes through the radially outermost points of the metal filamentary working reinforcing elements of the radially outermost working layer of the working reinforcement, is such that E2 5 0.40 mm, preferably E2 5 0.30 mm, more preferentially E2 5 0.20 mm.

[069] Indeed, in order also to improve the compromise between the vibratory discomfort caused by the oxidation pockets and the weight of the tyre, these embodiments propose also making use of the filamentary weft element(s) that do not conduct corrosive agents, or only conduct them a little, not only to reduce the thickness of the material(s) separating the bottom of the deepest cut of the axially central portion of the tread and the textile filamentary hooping reinforcing elements of the axially central portion of the tread, but also to reduce the thickness of the material(s) separating the textile filamentary hooping reinforcing elements of the axially central portion of the tread and the metal filamentary working reinforcing elements of the radially outermost working layer, which is thus the layer radially closest to the textile filamentary hooping reinforcing elements of the axially central portion of the tread. This thickness is represented by the mean radial distance E2.
Thus, analogously to El, although the risk of having corrosive agents reach the radially outermost working layer is increased by reducing the mean radial distance E2 separating said radially outermost working layer from the hoop reinforcement, the act of preventing the conduction of the corrosive agents by the filamentary weft element(s) makes it possible to not increase, or even to decrease, the total surface area of the oxidation pockets.

[070] Analogously to that described for El, in a first improved compromise compared to the prior art, it is possible to choose to greatly reduce the mean radial distance E2. An increase in the total surface area of the oxidation pockets will thus be prevented without necessarily reducing them, but the tyre will be significantly lightened. In a second improved compromise compared to the prior art, it is possible to choose to moderately reduce the mean radial distance E2. The total surface area of the oxidation pockets will thus be reduced, and the tyre will be moderately lightened. Which compromise to choose will be decided by those skilled in the art according to the intended use of the tyre.

[071] The mean radial distance E2 is determined in the same way as the mean radial distance El is determined mutatis mutandis.

[072] In a first variant, E2 0.05 mm, preferably E2 0.10 mm. The presence of a non-zero material thickness makes it possible to prevent direct contact between the textile filamentary hooping reinforcing elements and the metal filamentary working reinforcing elements and thus too great a propagation of corrosive agents from the hoop reinforcement to the working reinforcement Such a non-zero thickness also makes it possible to ensure mechanical decoupling of the working reinforcement and the hoop reinforcement.

[073] In a second variant, E2<0.05 mm. Unlike the first variant, the aim here is to minimize the material thickness, or even to eliminate it, so as to bring the textile filamentary hooping reinforcing elements into direct contact with the metal filamentary working reinforcing elements. Although corrosive agents could propagate on the metal filamentary working reinforcing elements that intersect the textile filamentary hooping reinforcing element(s), potentially conducting these corrosive elements, the filamentary weft reinforcing element(s) of the invention will reduce, or even eliminate, the propagation of corrosive agents on the metal filamentary working reinforcing elements that do not intersect the textile filamentary hooping reinforcing element(s) that conduct corrosive agents.

[074] Whether in the first or second variant, in some possible but nonlimiting embodiments, at least one of the textile filamentary hooping reinforcing elements is in contact with at least one of the metal filamentary working reinforcing elements of the radially outermost working layer. As explained above, bringing the textile filamentary hooping reinforcing elements into contact with at least one of the metal filamentary working reinforcing elements only leads to limited propagation of the corrosive agents in the working reinforcement, by virtue of the filamentary weft reinforcing element(s) of the invention.

[075] In some optional embodiments, in the axially central portion of the crown, the mean radial distance H between:
- the surface that passes through the radially innermost point of the or each deepest cut of the axially central portion of the tread and substantially parallel to the tread surface and - the radially outer surface that passes through the radially outermost points of the metal filamentary working reinforcing elements of the radially outermost working layer of the working reinforcement, is such that H <3.00 mm, preferably H 5 2.75 mm, more preferentially H 5 2.50 mm and even more preferentially H 5 2.35 mm.

[076] The relatively low value of El and optionally the relatively low value of E2 make it possible, if desired, to reduce the mean radial distance H and thus to lighten the tyre. In other embodiments it is possible, by reducing El and optionally by reducing E2, to retain a relatively high H value by increasing the tread pattern height, particularly in order to increase the number of kilometres that the tyre can travel.

[077] In one embodiment, the hoop reinforcement is axially delimited by two axial edges of the hoop reinforcement and comprises a strip helically wound over a plurality of circumferential turns so as to extend axially between the axial edges of the hoop reinforcement.

[078] In a first variant of this embodiment, the strip is helically wound over a plurality of circumferential turns such that, in the axially central portion of the crown, two adjacent circumferential turns of the strip do not overlap axially and radially with one another. Thus, with the strip having two longitudinal axial edges, in the axially central portion of the crown, the adjacent longitudinal axial edges of the two adjacent circumferential turns axially adjoin one another without forming any axial or radial overlap, or are axially remote from one another, without forming any axial or radial overlap between the two circumferential turns.
This thus prevents the formation of a double thickness in the hoop reinforcement. If the adjacent longitudinal axial edges of the two adjacent circumferential turns are axially remote from one another, this improves the compromise between high-speed endurance and the weight of the tyre by increased wrapping of those portions which are more sensitive at high speed, namely the portions axially outside the axially central portion, and by decreased wrapping of those portions which are less sensitive at high speed, namely the axially central portion.

[079] In a second variant of this embodiment, in the axially central portion of the crown, two adjacent circumferential turns form an axial and radial overlap between them. In this second variant, reference is generally made to "lapping", due to the strip turns overlapping one another in the manner of roof tiles.

[080] In order to make the manufacture of the tyre as efficient as possible, the strip comprises a plurality of textile filamentary hooping reinforcing elements that are substantially parallel to one another and are embedded in a polymer matrix, preferably an elastomer matrix.

[081] Advantageously, each textile filamentary hooping reinforcing element extends in a main hooping direction forming an angle which, in terms of absolute value, is less than or equal than 10 , preferably less than or equal to 7 and more preferentially less than or equal to 5 , with the circumferential direction of the tyre.

[082] In one advantageous embodiment, the textile filamentary hooping reinforcing elements are connected to one another by a plurality of filamentary weft elements that are substantially parallel to one another in a main weft direction that is not colinear with the main hooping direction, the filamentary weft elements being discontinuous with one another.

[083] Optionally, the main weft direction forms an angle of greater than or equal to 45 , preferably greater than or equal to 75 with the main hooping direction.

[084] In order to manufacture the hoop reinforcement and the strip of the embodiments described above, a strip is manufactured which, once it is helically wound around the working reinforcement, forms the hoop reinforcement. In a step of manufacturing a very wide fabric, the textile filamentary hooping reinforcing elements are arranged substantially parallel to one another. Then, the textile filamentary hooping reinforcing elements are separated into a first and a second ply of textile filamentary hooping reinforcing elements.

[085] Then, the textile filamentary hooping reinforcing elements are connected to one another by one or more filamentary weft elements extending over the whole width of the very wide fabric. To this end, the filamentary weft elements are interwoven in alternation with the textile filamentary hooping reinforcing elements of the first ply of filamentary warp elements and of the second ply of filamentary warp elements.

[086] In a subsequent sizing step, the textile filamentary hooping reinforcing elements and the filamentary weft elements are coated with one or more layers of one or more adhesive compositions, then the very wide fabric obtained beforehand is heat treated so as to obtain a sized very wide fabric.

[087] Then, in a subsequent calendering step, the sized very wide fabric is embedded in an elastomer matrix so as to obtain a calendered very wide fabric.

[088] Subsequently, in a cutting step, the calendered very wide fabric is cut up so as to obtain a plurality of narrow strips in which the textile filamentary hooping reinforcing elements extend in a direction substantially parallel to the direction of the greatest length of the strip.

[089] It will be noted that, during the step in which the textile filamentary hooping reinforcing elements are connected to one another by one or more filamentary weft elements, it is possible in some embodiments to use a shuttleless loom, for example a projectile loom, a loom with flexible or rigid rapiers, or a fluid-jet loom.
In the case of a fluid-jet loom, use will very advantageously be made of an air-jet loom in combination with tufted filamentary weft elements. Tufted filamentary weft element is understood to be a filamentary element comprising monofilaments, fibres or threads that do not stay within the circle circumscribed on a theoretical filamentary element corresponding to the filamentary weft element from which the monofilaments, fibres or threads that do not stay within the circle have been removed. Tufted filamentary weft element means that the filamentary weft element is neither smooth nor textured as described in application W02015016791.

[090] In other embodiments, use may be made of a shuttled loom that does not specifically require tufted filamentary weft elements.

[091] In some embodiments, each textile filamentary hooping reinforcing element comprises one or more organic synthetic monofilament(s), preferably an assembly comprising a plurality of organic synthetic monofilaments. Thus, the textile filamentary hooping elements do not conduct corrosive agents, and the propagation of these corrosive agents along the textile filamentary hooping elements arranged close to or in contact with attacks is prevented as much as possible.

[092] Optionally, the organic polymeric synthetic monofilaments are selected from polyester monofilaments, aliphatic polyamide monofilaments, aromatic polyamide monofilaments, polyketone monofilaments and assemblies of these monofilaments, preferably from polyester monofilaments, aliphatic polyamide monofilaments, aromatic polyamide monofilaments and assemblies of these monofilaments and even more preferentially from polyester monofilaments, aliphatic polyamide monofilaments and assemblies of aliphatic polyamide monofilaments and of aromatic polyamide monofilaments. Among the polyesters, PET (poly(ethylene terephthalate)), PEN
(poly(ethylene naphthalate)) and PEF (polyethylene-2,5-furandicarboxylate) will preferentially be chosen, and more particularly PET. Among the aliphatic polyamides, 6 or 6.6 aliphatic polyamides will preferentially be chosen. Among the aromatic polyamides, poly(meta-phenylene isophthalamides) and poly(para-phenylene terephthalamides) will preferentially be chosen.

[093] In some advantageous embodiments, the or each working layer is axially delimited by two axial edges of the or each working layer and comprises metal filamentary working reinforcing elements extending axially from one axial edge to the other axial edge of the or each working layer, substantially parallel to one another.

[094] Optionally, and regardless of the configuration of the working reinforcement, each metal filamentary working reinforcing element extends in a main direction forming an angle which, in terms of absolute value, is strictly greater than 10 , preferably ranging from 15 to 50 and more preferentially ranging from 20 to 35 , with the circumferential direction of the tyre.

[095] In a first configuration of the working reinforcement, the working reinforcement comprises a radially inner working layer and a radially outer working layer arranged radially outside the radially inner working layer. In this variant, the main direction in which each filamentary working reinforcing element of the radially innermost working layer extends and the main direction in which each filamentary working reinforcing element of the radially outermost working layer extends form, with the circumferential direction of the tyre, angles of opposite orientations. The angles may have identical or different absolute values.

[096] In a second configuration of the working reinforcement, the working reinforcement comprises a single working layer. In this second configuration, the radially outermost working layer is therefore the sole working layer. The presence of a single working layer makes it possible in particular to lighten the tyre, and therefore to reduce the energy dissipated by hysteresis of the crown and therefore to reduce the rolling resistance of the tyre. Thus, the working reinforcement is, apart from the working layer, free of any layer reinforced by filamentary reinforcing elements. The filamentary reinforcing elements of such reinforced layers excluded from the working reinforcement of the tyre comprise the metal filamentary reinforcing elements and the textile filamentary reinforcing elements. Very preferably, the working reinforcement consists of the single working layer.

[097] In one embodiment that makes it possible to reduce the weight of the metal filamentary working reinforcing elements, each metal filamentary working reinforcing element of the or each working layer consists of a metal monofilament.

[098] Optionally, with the tyre comprising two beads, two sidewalls each connecting each bead to the crown and a carcass reinforcement anchored in each bead, the carcass reinforcement extends radially into each sidewall and axially into the crown radially inside the crown reinforcement.

[099] In a first configuration of the carcass reinforcement, the carcass reinforcement comprises a single carcass layer. In this first configuration, apart from the single carcass layer, the carcass reinforcement is free of any layer reinforced by filamentary reinforcing elements. The filamentary reinforcing elements of such reinforced layers excluded from the carcass reinforcement of the tyre comprise metal filamentary reinforcing elements and textile filamentary reinforcing elements. Very preferentially, the carcass reinforcement consists of the single carcass layer.

[0100] In a second configuration of the carcass reinforcement, the carcass reinforcement comprises two carcass layers. In this second configuration, the main directions of the filamentary carcass reinforcing elements of the two carcass layers are preferably substantially parallel to each other.

[0101] Advantageously, with the carcass reinforcement comprising at least one carcass layer, the or each carcass layer is delimited axially by two axial edges of the or each carcass layer, and comprises textile filamentary carcass reinforcing elements extending axially from one axial edge to the other axial edge of the or each carcass layer.

[0102] In a first variant of the carcass reinforcement that can be used in combination with the first and second configuration of the carcass reinforcement and also with the first and second configuration of the working reinforcement, each filamentary carcass reinforcing element extends in a main direction of each filamentary carcass reinforcing element forming, with the circumferential direction of the tyre, an angle that is substantially constant between each axial edge of the or each carcass layer and that, as an absolute value, is greater than or equal to 60 , preferably ranging from 80 to 90 .

[0103] In a second variant of the carcass reinforcement that can be used in combination with the first and second configuration of the carcass reinforcement, with the working reinforcement comprising a single working layer, each filamentary carcass reinforcing element extends in a main direction of each filamentary carcass reinforcing element that forms, with the circumferential direction of the tyre:
- an angle, as an absolute value, of strictly less than 80 , in an axially central portion of the carcass layer extending axially in radial line with the working layer, - an angle, as an absolute value, ranging from 800 to 900, in two axially lateral portions of the carcass layer extending axially radially between the axially central portion and each axial edge of the carcass layer.

[0104] The invention will be better understood on reading the following description, which is given purely by way of nonlimiting example and with reference to the drawings, in which:
- Figure 1 is a view in a meridian sectional plane of a tyre according to a first embodiment of the invention, - Figure 2 is a schematic cutaway view of the tyre in Figure 1, illustrating the arrangement of the filamentary reinforcing elements in the crown, - Figure 3 is a top view of the tread of the tyre of Figure 1, - Figure 4 is a detail view of the axially central portion of the crown of the tyre of Figure 1, - Figure 5 is a view of the hoop reinforcement of the tyre of Figure 1, - Figure 6 is a photograph of a filamentary weft element and of a plurality of textile filamentary hooping reinforcing elements of the hoop reinforcement of Figure 5, - Figures 7 and 8 are views analogous to those of Figures 1 and 4 of a tyre according to a second embodiment, - Figure 9 is a view analogous to that of Figure 4 of a tyre according to a third embodiment, - Figure 10 is a view analogous to that of Figure 5 of the tyre according to the third embodiment, - Figures 11 and 12 are views analogous to those of Figures 9 and 10 of a tyre according to a fourth embodiment,

[0105] A frame of reference X, Y, Z corresponding to the usual axial (Y), radial (Z) and circumferential (X) directions, respectively, of a tyre is shown in the figures.

[0106] Figures 1 to 6 show a tyre in accordance with the invention and denoted by the general reference sign 10. The tyre 10 has substantially the shape of a torus about an axis of revolution substantially parallel to the axial direction Y. The tyre 10 is intended for a passenger vehicle and has the size 225/45 R17. In the various figures, the tyre 10 is depicted as new, i.e. when it has not yet been run.

[0107] The tyre 10 comprises a crown 12 comprising a tread 14 bearing a tread surface 15 intended to come into contact with the ground during running of the tyre 10.
The tread surface 15 is axially delimited by first and second axial ends 151, 152 passing through each point N arranged on either side of the mid-plane M and for which the angle between the tangent Ito the tread surface 15 and a straight line R parallel to the axial direction Y passing through this point is equal to 30 . The tread surface 15 has an axial width L
measured as the axial distance from the first axial end 151 to the second axial end 152.
The crown 12 comprises an axially central portion PO and two axially lateral portions P1 and P2 arranged axially on either side of the axially central portion PO with respect to the mid-plane M.

[0108] The axially central portion PO extends axially over an axial width LO
equal to 50% of the axial width L of the tread surface 15. Each first and second axially lateral portion P1, P2 has an axial width L1, L2 equal to 25% of the axial width L of the tread surface 15. The axially central portion PO is axially centred on the mid-plane M.

[0109] Referring to Figures 1, 3 and 4, the tread 14 comprises cuts comprising main circumferential cuts 72, 74, 76, 78, secondary circumferential cuts 80, 82, 84 and transverse cuts 90, 92, 94, 96, 98. The main circumferential cuts 72, 74, 76, 78 are circumferential grooves.

[0110] Referring to Figure 4, each main circumferential cut 72, 74, 76, 78 comprises two lateral faces Fr1, Fr2 and a bottom face Frd. Each main circumferential cut 72, 74, 76, 78 has a depth He ranging from 4.00 mm to the tread pattern height Hs, preferably ranging from 5.00 mm to the tread pattern height Hs and more preferentially ranging from 5.50 mm to the tread pattern height Hs. Each depth is greater than or equal to 50% of the tread pattern height Hs. Here, Hs=6.50 mm and here, each main circumferential cut 74, 76 has an equal depth He=Hs=6.50 mm and each main circumferential cut 72, 78 has a depth equal to 6.00 mm. Thus, each main circumferential cut 74, 76 is a deepest cut of the tyre 10 and in particular of the axially central portion PO.

[0111] The crown 12 also comprises a crown reinforcement 16 extending in the crown 12 in the circumferential direction X. The tyre 10 also comprises a sealing layer 18 that is airtight with respect to an inflation gas and is intended to delimit an internal cavity closed with a mounting support for the tyre 10 once the tyre 10 has been mounted on the mounting support, for example a rim.

[0112] The crown reinforcement 16 comprises a working reinforcement 20 and a hoop reinforcement 22.

[0113] The working reinforcement 20 comprises two working layers 24, 26. The radially outer working layer 26 is arranged radially outside the radially inner working layer 24. The radially outer working layer 26 is therefore the radially outermost working layer of the working reinforcement 20.

[0114] The hoop reinforcement 22 comprises at least one hooping layer and here comprises one hooping layer 28.

[0115] The crown reinforcement 16 is surmounted radially by the tread 14.
Here, the hoop reinforcement 22, in this case the hooping layer 28, is arranged radially outside the working reinforcement 20 and radially inside the tread 14. The hoop reinforcement 22 is therefore interposed radially between the working reinforcement 20 and the tread 14.

[0116] The tyre 10 comprises two sidewalls 30 that extend the crown 12 radially inwards.

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

[0117] The tyre 10 comprises a carcass reinforcement 34 anchored in each bead 32 and, in this instance, is wound around two bead wires 33. The carcass reinforcement 34 extends radially in each sidewall 30 and axially in the crown 12, radially on the inside of the crown reinforcement 16. The crown reinforcement 16 is arranged radially between the tread 14 and the carcass reinforcement 34. The carcass reinforcement 34 comprises at least one carcass layer and here comprises a single carcass layer 36. In this instance, the carcass reinforcement 34 consists of the single carcass layer 36.

[0118] Referring to Figure 4, each working layer 24, 26, hooping layer 28 and carcass layer 36 comprises a polymer matrix, here an elastomer matrix in which one or more filamentary reinforcing elements of the corresponding layer are embedded. The interfaces between two different adjacent layers are depicted by dotted lines. These layers will now be described with reference to Figures 2 to 5.

[0119] The hoop reinforcement 22, in this case the hooping layer 28, is delimited axially by two axial edges 221, 222 of the hoop reinforcement 22. The hoop reinforcement comprises a strip 40 helically wound over a plurality of circumferential turns Ci so as to extend axially between the axial edges 221, 222 of the hoop reinforcement 22.

[0120] A plurality of turns Cl to C4 are depicted in Figure 5, arranged in the axially central portion PO of the crown. The strip 40 comprises a plurality of textile filamentary hooping reinforcing elements 220 that are substantially parallel to one another and embedded in the elastomer matrix of the hooping layer 28 described above, such that the textile filamentary hooping reinforcing elements 220 are helically wound radially around the working reinforcement 20. The strip 40 is helically wound over a plurality of circumferential turns Ci such that, in the axially central portion PO of the crown 12, two adjacent circumferential turns Ci of the strip 40 do not overlap axially and radially with one another. Thus, as can be seen in Figure 5, in the axially central portion PO of the crown 12, there is no radial superposition between one of the textile filamentary hooping reinforcing elements of one circumferential turn Ci of the strip 40 and one of the textile filamentary hooping reinforcing elements of a circumferential turn Cj adjacent to the circumferential turn Ci.

[0121] Each textile filamentary hooping reinforcing element 220 extends in a main hooping direction DO forming an angle AF which, in terms of absolute value, is less than or equal than 100, preferably less than or equal to 70 and more preferentially less than or equal to 5 , with the circumferential direction X of the tyre 10. In this case, AF = -5 . The strip 40 comprises a density of 120 textile filamentary hooping reinforcing elements per decimetre of strip 40, this density being measured perpendicular to the direction DO.

[0122] Within the strip 40, the textile filamentary hooping reinforcing elements 220 are connected to one another by a plurality of filamentary weft elements 42 that are substantially parallel to one another in a main weft direction DT that is not colinear with the main hooping direction DO. The filamentary weft elements 42 are discontinuous with one another. The main weft direction DT forms an angle AT of greater than or equal to 45 , preferably greater than or equal to 75 , and in this case substantially equal to 900, with the main hooping direction DO.

[0123] The radially inner working layer 24 is delimited axially by two axial edges 241, 242.
The radially inner working layer 24 comprises metal filamentary working reinforcing elements 240 extending axially from the axial edge 24A to the other axial edge 24B in a manner substantially parallel to one another in a main direction Dl.
Analogously, the radially outer working layer 26 is delimited axially by two axial edges 261, 262. The radially outer working layer 26 comprises metal filamentary working reinforcing elements 260 extending axially from the axial edge 261 to the other axial edge 262 in a manner substantially parallel to one another in a main direction D2. The main direction D1 in which each filamentary working reinforcing element 240 of the radially inner working layer 24 extends and the main direction D2 in which each filamentary working reinforcing element 260 of the radially outer working layer 26 extends form angles ATI and AT2, respectively, of opposite orientations, with the circumferential direction X of the tyre 10. Each main direction D1, D2 forms an angle AT1, AT2, respectively, in terms of absolute value, strictly greater than 100, preferably ranging from 15 to 500 and more preferentially ranging from 20 to 35 , with the circumferential direction X of the tyre 10. In this case, All =-26 and AT2=+26 .

[0124] The carcass layer 36 is delimited axially by two axial edges 361, 362.
The carcass layer 36 comprises filamentary carcass reinforcing elements 360 extending axially from the axial edge 361 to the other axial edge 362 of the carcass layer 36 in a main direction D3 forming an angle AC which is substantially constant between each axial edge 361, 362, in terms of absolute value, of greater than or equal to 60 , preferably ranging from 80 to 90 and in this case AC=+90 , with the circumferential direction X of the tyre 10.

[0125] Figure 6 depicts a sectional view of the hoop reinforcement 22 in a sectional plane perpendicular to the direction DO and comprising one of the filamentary weft elements 42.
Referring to Figure 6, each filamentary hooping reinforcing element 220 comprises one or more organic synthetic monofilament(s), preferably comprises an assembly comprising a plurality of organic synthetic monofilaments. The organic polymeric synthetic monofilaments are selected from polyester monofilaments, aliphatic polyamide monofilaments, aromatic polyamide monofilaments, polyketone monofilaments and assemblies of these monofilaments, preferably from polyester monofilaments, aliphatic polyamide monofilaments, aromatic polyamide monofilaments and assemblies of these monofilaments and even more preferentially from polyester monofilaments, aliphatic polyamide monofilaments and assemblies of aliphatic polyamide monofilaments and of aromatic polyamide monofilaments. In this instance, each filamentary hooping reinforcing element 220 conventionally comprises two multifilament strands, each multifilament strand consisting of a spun yarn of aliphatic polyamide, in this instance nylon, monofilaments, with a thread count equal to 94 tex, these two multifilament strands being twisted in a helix individually at 320 turns per metre in one direction and then twisted together in a helix at 320 turns per metre in the opposite direction. These two multifilament strands are wound in a helix around each other. As a variant, use could be made of a filamentary hooping reinforcing element 220 comprising one multifilament strand consisting of a spun yarn of aliphatic polyamide, in this case nylon, monofilaments with a thread count equal to 140 tex, and one multifilament strand consisting of a spun yarn of aromatic polyamide, in this case aramid, monofilaments with a thread count equal to 167 tex, these two multifilament strands being twisted in a helix individually at 290 turns per metre in one direction and then twisted together in a helix at 290 turns per metre in the opposite direction. These two multifilament strands are wound in a helix around each other. This variant will give AT1=-29 and AT2=+29 .

[0126] Still referring to Figure 6, each filamentary weft element 42 comprises a plurality of textile monofilaments and/or a plurality of textile fibres selected from organic polymeric synthetic fibres and monofilaments, inorganic polymeric synthetic fibres and monofilaments, and assemblies of these monofilaments and fibres. More specifically, at least 50%, preferably at least 75% and here 100% of the weight of each filamentary weft element 42 consists of textile monofilaments and/or textile fibres selected from organic polymeric synthetic fibres and monofilaments, inorganic polymeric synthetic fibres and monofilaments, and assemblies of these monofilaments and fibres. Furthermore, at least 50%, preferably at least 75% and here 100% of the cumulative length of the filamentary weft elements 42 comprises a plurality of textile monofilaments and/or textile fibres selected from organic polymeric synthetic fibres and monofilaments, inorganic polymeric synthetic textile fibres and monofilaments, and assemblies of these monofilaments and fibres.

[0127] At least one of the filamentary weft elements 42 comprises a plurality of organic polymeric synthetic textile fibres and/or monofilaments. More specifically, at least 50%, preferably at least 75% and here 100% of the weight of each filamentary weft element 42 consists of textile monofilaments and/or textile fibres selected from organic polymeric synthetic fibres and monofilaments. Furthermore, at least 50%, preferably at least 75%, and here 100%, of the cumulative length of the filamentary weft elements 42 comprises a plurality of organic polymeric synthetic fibres and/or monofilaments.

[0128] The organic polymeric synthetic fibres and monofilaments are selected from polyester fibres and monofilaments, polyamide fibres and monofilaments, polyketone fibres and monofilaments, polyurethane fibres and monofilaments, acrylic fibres and monofilaments, polyolefin fibres and monofilaments, polyether ether ketone fibres and monofilaments and assemblies of these monofilaments and of these fibres, preferably from polyester fibres and monofilaments, polyamide fibres and monofilaments and assemblies of these monofilaments and of these fibres, and here the organic synthetic fibres and monofilaments are polyester fibres and monofilaments.

[0129] In this instance, each filamentary weft element 42 comprises, here consists of, two strands each comprising a core and a layer coating the core, the core comprising a plurality of polyester monofilaments and the layer comprising a plurality of polyester fibres. The sum of the thread counts of the strands of each filamentary weft element 42 is equal to 22 tex.
The thread count of each filamentary weft element 42 ranges from 1 to 20 tex and preferably from 10 to 15 tex. Here, it is 11 tex. In order to manufacture each filamentary weft element 42, the two strands are helically wound around one another at a twist of 1100 turns per metre, then each filamentary weft element 42 has a twist equal to 1100 turns per metre. The moisture regain of each filamentary weft element 42 is equal to 1.8%.

[0130] The density of the filamentary weft elements 42 ranges from 3.0 to 8.0 filamentary weft elements per dm of length of the strip 40, preferably from 3.0 to 6.0 filamentary weft elements per dm of length of the strip 40, and more preferentially from 3.0 to 5.5 filamentary weft elements per dm of length of the strip 40. Here, the density of the filamentary weft elements 42 is equal to 5.0 filamentary weft elements per dm of length of the strip 40.

[0131] Each metal filamentary working reinforcing element 240, 260 comprises an assembly of two steel monofilaments helically wound at a pitch of 14 mm, each steel monofilament having a diameter equal to 0.30 mm. For the sake of clarity, Figure 4 depicts the circle circumscribed on this assembly, the diameter of which is equal to the diameter of each metal filamentary working reinforcing element 240, 260. In one variant, each metal filamentary working reinforcing element 240, 260 consists of a steel monofilament having a diameter equal to 0.30 mm. More generally, the steel monofilaments have diameters ranging from 0.25 mm to 0.32 mm. In yet another variant, use could also be made of an assembly of six steel monofilaments having a diameter equal to 0.23 mm and comprising an internal layer of two monofilaments helically wound together at a pitch of 12.5 mm in a first direction, for example the Z direction, and an external layer of four monofilaments helically wound together around the internal layer at a pitch of 12.5 mm in a second direction opposite to the first direction, for example the S direction.

[0132] Each filamentary carcass reinforcing element 360 conventionally comprises two multifilament strands, each multifilament strand consisting of a spun yarn of polyester, in this case of PET, monofilaments, these two multifilament strands being twisted in a helix individually at 240 turns per metre in one direction and then twisted together in a helix at 240 turns per metre in the opposite direction. Each of these multifilament strands has a thread count equal to 220 tex. In other variants, use could be made of thread counts equal to 144 tex and twists equal to 420 turns per metre or thread counts equal to 334 tex and twists equal to 270 turns per metre.

[0133] Figure 4 depicts:
- the surface 100 that passes through the radially innermost point of each deepest cut 74, 76 of the axially central portion PO of the tread 14 and substantially parallel to the tread surface 15, and - the radially outer surface 102 that passes through the radially outermost points of the textile filamentary hooping reinforcing elements 220 that are radially outermost among the textile filamentary hooping reinforcing elements 220, - the radially inner surface 104 that passes through the radially innermost points of the textile filamentary hooping reinforcing elements 220 that are radially innermost among the textile filamentary hooping reinforcing elements 220, - the radially outer surface 106 that passes through the radially outermost points of the metal filamentary working reinforcing elements 260 of the radially outermost working layer 26 of the working reinforcement 20.

[0134] In the axially central portion PO of the crown 12, the mean radial distance El between the surface 100 and the radially outer surface 102 is such that El 5 2.00 mm.
Here, El 5 1.80 mm, preferably El 5 1.50 mm. In addition, El 0.20 mm, preferably El 0.50 mm and more preferentially El 1.00 mm. In this instance, El =1.50 mm.

[0135] In the axially central portion PO of the crown 12, the mean radial distance E2 between the radially inner surface 104 and the radially outer surface 106 is such that E2 0.40 mm and preferably E2 5 0.30 mm. In addition, E2 a 0.05 mm, preferably E2 a 0.10 mm. In this instance, E2=0.23 mm.

[0136] In the axially central portion PO of the crown 12, the mean radial distance H between the surface 100 and the radially outer surface 106 is such that H 5 3.00 mm, preferably H 5 2.75 mm, more preferentially H 5 2.50 mm and even more preferentially H 5 2.35 mm. In this instance, H=2.34 mm.

[0137] A tyre according to a second embodiment will now be described with reference to Figure 7 and to Figure 8. Elements similar to those of the first embodiment are denoted by identical references.

[0138] Unlike the tyre according to the first embodiment, the working reinforcement 20 of the tyre 10 according to the second embodiment comprises a single working layer 26, which is therefore the radially outermost working layer of the working reinforcement 20.

[0139] In addition, each filamentary carcass reinforcing element 360 extends in a main direction D3 of each filamentary carcass reinforcing element 360 forming, with the circumferential direction X of the tyre 10:
- an angle, as an absolute value, of strictly less than 800, in an axially central portion of the carcass layer extending axially in radial line with the working layer 26, - an angle, as an absolute value, ranging from 80 to 90 , in two axially lateral portions of the carcass layer 36 extending axially radially between the axially central portion and each axial edge of the carcass layer 36.

[0140] Tyres comprising a single working layer and a carcass layer as described above, and the processes for manufacturing same, are in particular known from EP3489035, FR2797213 and FR1413102.

[0141] A tyre according to a third embodiment will now be described with reference to Figure 9 and to Figure 10. Elements similar to those of the previous embodiments are denoted by identical references.

[0142] Unlike the first embodiment, two adjacent circumferential turns Ci of strip 40 form a radial and axial overlap with one another.

[0143] Figure 9 depicts the textile filamentary hooping reinforcing elements in the form of white circles when they belong to a given circumferential turn Ci and in the form of circles filled with dots when they belong to the circumferential turn Ci+1 adjacent to the circumferential turn Ci.

[0144] In this embodiment, the radially outer surface 102 is, in accordance with the invention, the surface that passes through the radially outermost points of the textile filamentary hooping reinforcing elements 220 that are radially outermost among the textile filamentary hooping reinforcing elements 220. Here, the textile filamentary hooping reinforcing elements 220 that are radially outermost among the textile filamentary hooping reinforcing elements 220 are the textile filamentary hooping reinforcing elements 220 of each circumferential turn that radially overlap the textile filamentary hooping reinforcing elements 220 of the adjacent circumferential turn.

[0145] In addition, in this embodiment, the radially inner surface 104 is, in accordance with the invention, the surface that passes through the radially innermost points of the textile filamentary hooping reinforcing elements 220 that are radially innermost among the textile filamentary hooping reinforcing elements 220. Here, the textile filamentary hooping reinforcing elements 220 that are radially innermost among the textile filamentary hooping reinforcing elements 220 are both the textile filamentary hooping reinforcing elements 220 of each circumferential turn that are radially overlapped by the textile filamentary hooping reinforcing elements 220 of the adjacent circumferential turn, and the textile filamentary hooping reinforcing elements 220 of each circumferential turn that are not overlapped by other textile filamentary hooping reinforcing elements 220.

[0146] A tyre according to a fourth embodiment will now be described with reference to Figure 11 and to Figure 12. Elements similar to those of the previous embodiments are denoted by identical references.

[0147] Similarly to the first and second embodiments, the tyre 10 according to the fourth embodiment is such that the strip 40 is helically wound over a plurality of circumferential turns Ci such that, in the axially central portion PO of the crown 12, two adjacent circumferential turns Ci of the strip 40 do not overlap axially and radially with one another.
Thus, as can be seen in Figures 11 and 12, in the axially central portion PO
of the crown 12, there is no radial superposition between one of the textile filamentary hooping reinforcing elements of one circumferential turn Ci of the strip 40 and one of the textile filamentary hooping reinforcing elements of a circumferential turn Cj adjacent to the circumferential turn Ci. Unlike the first and second embodiments, in the axially central portion of the crown, the adjacent longitudinal axial edges of the two adjacent circumferential turns are axially remote from one another, without forming any axial or radial overlap between the two circumferential turns.

[0148] COMPARATIVE TESTS

[0149] First comparative test

[0150] A comparison was made between two control tyres TO and T1 which are identical to one another except for their hoop reinforcement and also for the radial distance E2 during an aggressive running test, described below.

[0151] The control tyre TO comprises a hoop reinforcement in which the textile filamentary weft reinforcing elements are not connected to one another by any filamentary weft element.
In other words, the hoop reinforcement of the control tyre TO is free of filamentary weft elements. In addition, E2=0.11 mm.

[0152] The control tyre T1 comprises a hoop reinforcement in which the textile filamentary weft reinforcing elements are connected to one another by filamentary weft elements comprising cotton fibres. In addition, E2=0.30 mm.

[0153] Each tested tyre was inflated to a pressure equal to 80% of its nominal inflation pressure on a passenger vehicle on which it is intended, and able, to be mounted. This vehicle was run on a circuit comprising a portion of tarmacked road surface and a portion of road surface covered with crushed stones such that it has ridges and protruding parts, making it possible to attack the tread of the tyre being tested. The vehicle makes several laps of this circuit, to enable the tread to be attacked by the crushed stones, whether this be as it passes over the portion of the road surface covered with crushed stones, or when it passes into the portion of tarmacked road surface in the event that crushed stones are trapped in the tread. The circuit also comprises a wet portion comprising a tray of salt water, enabling corrosive agents to enter at the points at which the stones have attacked the tyre.
After sufficient running, for example several thousand kilometres, the tread and the hoop reinforcement are removed from each tyre tested and the radially outermost working layer of the working reinforcement is analyzed.

[0154] During this analysis, firstly the number Np of attacks present on the radially outermost working layer of the working reinforcement is counted. In addition, the surface area of each oxidation pocket is measured. The total surface area St of all the oxidation pockets of the radially outermost working layer of the working reinforcement is then deduced therefrom.

[0155] The various characteristics of the control tyres TO, T1 and also the results of the aggressive running test described above are collated in Table 1 below.

[0156] The number of attacks Np is given in base 100 with respect to the control tyre T1. A
number Np of greater than 100 means that the radially outermost working layer of the tyre tested has more attacks than the control tyre T1.

[0157] Similarly, the total surface area St is given in base 100 with respect to the control tyre TI. A total surface area St of greater than 100 means that the radially outermost working layer of the tyre tested has a total surface area of oxidation pockets that is greater than that of the control tyre TI.
Tyre T1 Tyre TO
E2 (mm) 0.30 0.11 Presence of filamentary weft Yes No elements Np 100 165 St 100 49 Table 1

[0158] This first comparative test shows that the presence of cotton filamentary weft elements in the control tyre T1 causes a significant increase in the total surface area St of the oxidation pockets compared to the control tyre TO which does not have any filamentary weft elements in the hoop reinforcement.

[0159] It will be noted that this is all the more unexpected, on the one hand because the number of attacks Np is much greater in the control tyre TO than in the control tyre T1 and on the other hand because the mean radial distance E2 is significantly smaller in the control tyre TO than in the control tyre T1. Indeed, with a greater number of attacks Np, a greater number of oxidation pockets would be expected, and therefore a greater total surface area St of oxidation pockets in the control tyre TO than in the control tyre T1. In addition, with a smaller mean radial distance E2 and therefore a smaller material thickness, easier propagation of the corrosive agents would be expected, and therefore a greater total surface area St of oxidation pockets in the control tyre TO than in the control tyre TI.

[0160] Second comparative test

[0161] A comparison was made between control tyres T2, 13 and a tyre 10 according to the first embodiment described above.

[0162] The control tyre T3 comprises filamentary hooping reinforcing elements identical to those of the tyre 10 according to the first embodiment. In the control tyre 12, each filamentary hooping reinforcing element comprises two multifilament strands, each multifilament strand consisting of a spun yarn of aliphatic polyamide, in this instance nylon, monofilaments, with a thread count equal to 140 tex, these two multifilament strands being twisted in a helix individually at 250 turns per metre in one direction and then twisted together in a helix at 250 turns per metre in the opposite direction.

[0163] In addition, in the control tyre T3 and the tyre 10 according to the first embodiment, El =1.50 mm. In the control tyre T2, El =2.30 mm.

[0164] Moreover, E2=0.44 mm in the control tyre 12, E2=0.38 mm in the control tyre T3, while E2=0.23 mm in the tyre 10 according to the first embodiment.

[0165] In addition, the filamentary weft elements comprise cotton fibres for the control tyres T2 and T3, while the filamentary weft elements of the tyre 10 according to the first embodiment are as described above.

[0166] The control tyres 12 and 13, and the tyre 10 according to the first embodiment, were compared in the aggressive running test described above. The weights of the tyres and the rolling resistance thereof was also measured in accordance with Regulation No 117 of the United Nations Economic Commission for Europe.

[0167] The various characteristics of the control tyres T2 and T3 and of the tyre 10 according to the first embodiment, and also the results of the aggressive running test and the measurements of weight and rolling resistance, are collated in Table 2 below.
Tyre 12 Tyre T3 Tyre 10 El (mm) 2.30 1.50 1.50 E2 (mm) 0.44 0.38 0.23 Filamentary weft Cotton Cotton PET
elements Np 100 356 St 100 179 Weight (kg) 8.72 8.30 8.30 Rolling resistance 7.52 7.08 7.08 (kg/T) Table 2

[0168] Comparing the control tyres 12 and 13, it is noted that the mean radial distance El and the mean radial distance E2 have been significantly reduced so as to lighten the control tyre 13 compared to the control tyre 12. Thus, the thickness of the material(s) protecting the textile filamentary hooping reinforcing elements from attacks has been significantly reduced and the thickness of the material(s) protecting the metal filamentary working reinforcing elements from the corrosive agents propagated by the filamentary weft elements has been significantly reduced. Thus, a significant increase in the number of attacks Np is observed and consequently an increase in the total surface area of the oxidation pockets in the control tyre 13, due to the significant propagation of the corrosive agents via the cotton filamentary weft elements, as was demonstrated during the first aggressive running test.
It should also be noted that this is all the more noteworthy because, since the filamentary hooping reinforcing elements of the control tyre T2 are wider than those of the tyres T3 and 10 according to the first embodiment, these filamentary hooping reinforcing elements of the control tyre 12 are more likely to propagate corrosive agents.

[0169] Comparing the control tyre T3 and the tyre 10 according to the first embodiment, it is observed that, for an identical mean radial distance El, the number of attacks Np is substantially the same. Nevertheless, a much lower total surface area St of the oxidation pockets is observed for the tyre 10 according to the first embodiment, despite a smaller E2 value than the control tyre 13. In accordance with the invention, this is due to the presence of filamentary weft elements that limit, or even eliminate, the propagation of corrosive agents in the hoop reinforcement.

[0170] Comparing the control tyre T2 and the tyre 10 according to the first embodiment, it is observed that, for much smaller mean radial distances El and E2 for the tyre 10 according to the first embodiment, the tyre 10 according to the first embodiment has a total surface area St of oxidation pockets which is not significantly greater than the total surface area St of oxidation pockets of the control tyre T2; and in any case, the increase in the total surface area St of the oxidation pockets is not proportional to the degree to which the tyre has been lightened, nor is it proportional to the gain in rolling resistance.

[0171] Thus, in conclusion, by reducing El and/or E2 and thus by lightening the tyre and thus by reducing the rolling resistance thereof, it is possible to limit, or even reduce, the formation of oxidation pockets using filamentary weft elements in accordance with the invention that prevent the propagation of corrosive agents.

[0172] The invention is not limited to the embodiments described above.

[0173] It will be appreciated that it is entirely possible, in order to achieve the technical effect of the invention, to further reduce the thicknesses El and E2. Thus, it is possible to envisage tyres in which El 1.40 mm, and even more preferentially El 1.20 mm, which would make it possible to further lighten the tyre. It is also possible to envisage tyres in which E2 < 0.20 mm, which would also make it possible to further lighten the tyre.

[0174] It is also possible to envisage, should it prove necessary to reinforce the carcass reinforcement 34, a carcass reinforcement 34 comprising two carcass layers.

Claims

- 32 -

1. Tyre (10) comprising a crown (12) comprising a tread (14) bearing a tread surface (15), the crown (12) comprising an axially central portion (PO) extending over an axial width (LO) equal to 50% of the axial width (L) of the tread surface (15) and axially centred over the mid-plane (M) of the tyre (10), the axially central portion (PO) of the tread (14) comprising at least one deepest cut (74, 76) of the axially central portion (PO) of the tread (14), the crown (12) comprising a crown reinforcement (16) comprising:
- a working reinforcement (20) comprising at least one radially outermost working layer (26) of the working reinforcement (20), the radially outermost working layer (26) comprising metal filamentary working reinforcing elements (260), - a hoop reinforcement (22) comprising a plurality of textile filamentary hooping reinforcing elements (220) helically wound radially around the working reinforcement (20) and connected to one another by one or more filamentary weft element(s) (42), the hoop reinforcement (22) being arranged radially outside the working reinforcement (20) and radially inside the tread (14), characterized in that, in the axially central portion (PO) of the crown (12), the mean radial distance E 1 between:
- the surface (100) that passes through the radially innermost point of the or each deepest cut (74, 76) of the axially central portion (PO) of the tread (14) and substantially parallel to the tread surface (15) and - the radially outer surface (102) that passes through the radially outermost points of the textile filamentary hooping reinforcing elements (220) that are radially outermost among the textile filamentary hooping reinforcing elements (220), is such that El 2.00 mm, and in that the or at least one of the filamentary weft element(s) (42) comprises a plurality of textile monofilaments and/or a plurality of textile fibres selected from organic polymeric synthetic fibres and monofilaments, inorganic polymeric synthetic fibres and monofilaments, and assemblies of these monofilaments and fibres.

2. Tyre (10) according to the preceding claim, wherein El ~ 1.80 mm, preferably El ~
1.50 mm, more preferentially El 1.40 mm and even more preferentially El 1.20 mm.

3. Tyre (10) according to either one of the preceding claims, wherein El 0.20 mm, preferably El 0.50 mm and more preferentially El 1.00 mm.

4. Tyre (10) according to any one of the preceding claims, wherein the or at least one of the filamentary weft element(s) (42) comprises a plurality of organic polymeric synthetic textile fibres and/or monofilaments.

5. Tyre (10) according to any one of the preceding claims, wherein the organic polymeric synthetic fibres and monofilaments are selected from polyester fibres and monofilaments, polyamide fibres and monofilaments, polyketone fibres and monofilaments, polyurethane fibres and monofilaments, acrylic fibres and monofilaments, polyolefin fibres and monofilaments, polyether ether ketone fibres and monofilaments and assemblies of these monofilaments and of these fibres, preferably from polyester fibres and monofilaments, polyamide fibres and monofilaments and assemblies of these monofilaments and of these fibres, and more preferentially the organic synthetic fibres and monofilaments are polyester fibres and monofilaments.

6. Tyre (10) according to any one of the preceding claims, wherein, in the axially central portion (PO) of the crown (12), the mean radial distance E2 between:
- the radially inner surface (104) that passes through the radially innermost points of the textile filamentary hooping reinforcing elements (220) that are radially innermost among the textile filamentary hooping reinforcing elements (220), - the radially outer surface (106) that passes through the radially outermost points of the metal filamentary working reinforcing elements (260) of the radially outermost working layer (26) of the working reinforcement (20), is such that E2 0.40 mm, preferably E2 0.30 mm, more preferentially E2 0.20 mm.

7. Tyre (10) according to the preceding claim, wherein E2 0.05 mm, preferably E2 0.10 mm.

8. Tyre (10) according to any one of the preceding claims, wherein at least one of the textile filamentary hooping reinforcing elements (220) is in contact with at least one of the metal filamentary working reinforcing elements (260) of the radially outermost working layer (26).

9. Tyre (10) according to any one of the preceding claims, wherein, in the axially central portion (PO) of the crown (12), the mean radial distance H between:
- the surface (100) that passes through the radially innermost point of the or each deepest cut (74, 76) of the axially central portion (PO) of the tread (14) and substantially parallel to the tread surface (15) and - the radially outer surface (106) that passes through the radially outermost points of the metal filamentary working reinforcing elements (260) of the radially outermost working layer (26) of the working reinforcement (20), is such that H 5 3.00 mm, preferably H 5 2.75 mm, more preferentially H 5 2.50 mm and even more preferentially H 5 2.35 mm.

10. Tyre (10) according to any one of the preceding claims, wherein the hoop reinforcement (22) is axially delimited by two axial edges (221, 222) of the hoop reinforcement (22) and comprises a strip (40) helically wound over a plurality of circumferential turns (C1, C2, C3, C4, C5) so as to extend axially between the axial edges (221, 222) of the hoop reinforcement (22).

11. Tyre (10) according to the preceding claim, wherein the strip (40) is helically wound over a plurality of circumferential turns (C1, C2, C3, C4, C5) such that, in the axially central portion (PO) of the crown (12), two adjacent circumferential turns (C1, C2, C3, C4, C5) of the strip (40) do not overlap axially and radially with one another.

12. Tyre (10) according to Claim 10 or 11, wherein the strip (40) comprises a plurality of textile filamentary hooping reinforcing elements (220) that are substantially parallel to one another and are embedded in a polymer matrix, preferably an elastomer matrix.

13. Tyre (10) according to any one of the preceding claims, wherein each textile filamentary hooping reinforcing element (220) extends in a main hooping direction (DO) forming an angle which, in terms of absolute value, is less than or equal than 10 , preferably less than or equal to 7 and more preferentially less than or equal to 5 with the circumferential direction (X) of the tyre.

14. Tyre (10) according to the preceding claim, wherein the textile filamentary hooping reinforcing elements (220) are connected to one another by a plurality of filamentary weft elements (42) that are substantially parallel to one another in a main weft direction (DT) that is not colinear with the main hooping direction (DO), the filamentary weft elements (42) being discontinuous with one another.

15. Tyre (10) according to Claim 14, wherein the main weft direction (DT) forms an angle of greater than or equal to 45 , preferably greater than or equal to 75 with the main hooping direction (DO).