MXPA00004255A - Crown ply reinforcement for heavy vehicle tyre - Google Patents

Abstract

The invention concerns a tyre (P) with radial body ply reinforcement (1) with maximum axial width S0, comprising a crown ply reinforcement (3) formed of at least two working breaker strips(32, 34) of inextensible reinforcing elements, criss-crossed from one breaker strip to the other forming with the circumferential direction angles between 10°and 45°, said breaker strips having axial widths L32, L34 not less than 80%of the width S0, and, radially arranged between said working breaker strips, an additional breaker (33) made of reinforcing elements substantially parallel to the circumferential direction, the working breaker strips (32, 34) of widths L32, L34 greater than the width L33 of the additional breaker (33) by at least 16%of the width S0, being on either side of the equatorial plane and in the immediate axial extension of the additional breaker (33) coupled over an axial distance l not less than 3%of the width S0, to be then separated by a section (4) of rubber mixture with a thickness not less than 2 mm.

Description

PNEUMATIC CROWN ARMOR FOR GREAT TONNAGE VEHICLES Description of the Invention The present invention relates to a radial carcass reinforcement tire, anchored on both sides, at least to a bead rod, and having a crown reinforcement constituted by at least two fabrics, work calls, superimposed and formed by parallel wires or cables in each fabric and crossed from one fabric to the next, which form with the circumferential direction of the tire angles, at most, equal to 45 ° in absolute value. More particularly, it relates to a tire of the type used by heavy goods vehicles, in which the ratio between the height on rim H and its maximum axial width S is, at most, equal to 0.80, and intended to equip a medium or large load vehicle, such as a truck, bus, trailer, etc. Some current tires, called "road", are destined to roll at high speed and for increasingly long journeys, due to the improvement of the road network and the growth of the REF. : 119858 highway network in the world. The set of conditions, in which it is intended to roll a tire of this type, allows, without any doubt, an increase in the number of kilometers traveled, being less tire wear; on the contrary, the resistance of the latter and, in particular, of the crown reinforcement is penalized. French Patent No. 2 419 185 teaches that the type of tire considered, with a small H / S ratio, while having numerous advantages, also comprises a number of drawbacks, such as the mediocre grip of the equatorial zone of the tire. tread band or a location of high pressures in the region of the edges of the tread, due to the decrease of the contact area in the longitudinal direction of the tire In order to remedy the aforementioned drawbacks, the aforementioned French patent advocates arranging between the carcass reinforcement and the radially inner working fabric, in two areas distant from the equatorial plane, two limiting blocks, each constituted by two superimposed fabrics of inextensible cables, crossed from one fabric to another, forming with the circumferential direction opposite angles, at most, equal in absolute value to half the smallest angle used in the work fabrics, and dif of 0o. The application of the solution described above, its application to a tire with H / s form ratio, at most, equal to 0.80, in particular, at most, equal to 0.6, and intended to equip a large vehicle. tonnage, does not allow satisfactory strength of the crown reinforcement. The lack of resistance refers both to the fatigue strength of the crown fabrics and, in particular, to the resistance to separation between the ends of the fabrics, and to the fatigue resistance of the portion wires. of carcass reinforcement located under the crown reinforcement, strongly influencing in the first insufficiency the operating temperature that reigns at the edges of the work fabrics, either in straight line running, or in running with changes of direction.

The French application 94/015736 aims to improve the strength of the crown reinforcement of a tire for heavy goods vehicles, with a shape ratio, at most, equal to 0.60, said reinforcement comprising at least two fabrics of working crowns of inextensible cables, crossed from one fabric to the next, forming with the circumferential direction angles between 10 ° and 45 °, said fabrics having widths at least equal to 80% of the maximum axial width S0 of the carcass reinforcement. This application proposes to arrange, on the one hand, between the carcass reinforcement and the work fabric radially closest to the axis of rotation, an axially continuous fabric, formed by inextensible metallic cables forming an angle with the circumferential direction, at least equal to 60 °, and whose axial width is at least equal to the axial width of the shorter working crown fabric and, on the other hand, between the two working crown fabrics, an additional formed fabric by metallic elements, oriented substantially parallel to the circumferential direction, the axial width of said fabric being at least equal to 0.7 So, and its modulus of elasticity being at least equal to the module of the same name. of the most extensible work fabric.

The French application No. 96/02178, with a view to reducing the operating temperature of a radial carcass reinforcement tire of the type used by heavy-duty vehicles, while achieving a solution as efficient as it is economical, advocates adding to said carcass reinforcement a crown reinforcement comprising at least two inextensible cable working crown webs, crossed from one fabric to another, forming with the circumferential direction angles comprised between 10 ° and 45 °, and further comprises, in the absence of any fabric formed by inextensible cables forming with the circumferential direction an angle greater than 45 °, an additional fabric, axially continuous, formed by metal elements oriented substantially parallel to the circumferential direction, and placed radially between the working fabrics, said additional fabric having an axial width, at least, equal to 1.05 times the axial width of the a wider working crown fabric. Even when the problems concerning the separation between work fabrics and the fatigue resistance of the carcass reinforcement cables seem to be solved, in one case, and the operating temperatures drop sharply, in the other case, the prolonged running of the Thus constructed tires, on the contrary, cause breakages due to fatigue of the cables of the additional fabric and, more particularly, of the edges of said fabric, whether the so-called triangulation fabric is present or not. It is always possible to change the reinforcement elements considered and, in particular, to choose cables of different construction or cables of greater resistance to breakage. The previous solution, certainly easy, is always onerous. In order to remedy the above disadvantages and improve the strength of the crown reinforcement of the type of tire studied, without raising its cost, the radial carcass reinforcement tire according to the invention, of maximum axial width S0, comprising a crown reinforcement formed by at least two working crown webs of inextensible reinforcing elements, crossed from one fabric to another, forming with the circumferential direction angles comprised between 10 ° and 45 °, having said webs, widths axial, at least, equal to 80% of the width So and an additional fabric of reinforcement elements substantially parallel to the circumferential direction, radially placed between the said work fabrics, is characterized in that the working fabrics of widths greater than the width of the additional fabric in at least 16% of the width S0 are on either side of the equatorial plane and in the immediate axial extension of the web ad These are coupled at an axial distance of at least 3.5% of the width Ss, to be subsequently decoupled by rubber mixing profiles at least in the rest of the width common to the two work fabrics mentioned. . The thickness of the decoupling profiles between fabrics, measured at the ends of the less wide working fabric, will be at least equal to two millimeters and, preferably, greater than 2.5 millimeters. It is to be understood by coupled fabrics, whose respective reinforcing elements are radially spaced apart, at most, 1.5 mm, said radial thickness being measured radially, between the generatrices, respectively, upper and lower of said reinforcing elements. It must be understood as an inextensible element, an element, cable or monofilament, which has an elongation less than 0.2% when subjected to a tensile force equal to 10% of the breaking load. In the case of the considered tire, the inextensible reinforcing elements are preferably inextensible steel wire ropes. Reinforcement elements, wires or cables, oriented substantially parallel to the circumferential direction, are elements that form with the aforesaid direction angles comprised in the range of +2, 5 °, -2.5 ° around 0o. The additional fabric advantageously has a modulus of elasticity, under tensile stress, at most, equal to the module of the same name of the most extensible work fabric. A modulus of tensile elasticity of a cable fabric results from the tensile tension, exerted according to the direction of the cables, necessary to obtain a given relative elongation e, said module being a tangent module. By modulus of elasticity of the additional fabric, much cone, equal to the module of the same name of the most extensible work fabric, it must be understood that the tangent modulus of the additional fabric, whatever the relative elongation, is, at most, equal to the tangent modulus of the most extensible work fabric, whatever the relative elongation, the fabric being more extensible, the fabric that, for each value of the tensile stress, presents a relative elongation greater than that of the other fabric for the same tension. Advantageously and in order to facilitate the manufacture of the tire, the module of the additional fabric will be such that for a relative elongation between 0% and 0.4%, it will be small and for relative elongations greater than 0.4% , is, at most, equal to the highest tensile modulus of the most extensible work fabric. Working fabrics generally have unequal axial widths. The work fabric radially further to the outside may be less axially wider than the work fabric radially disposed further inside: it is advantageous, then, that the crown reinforcement be completed radially to the outside by a supplementary fabric, called protection, of elements of reinforcement, called elastic, oriented with respect to the circumferential direction an angle comprised between 10 ° and 45 ° and of the same direction as the angle formed by the inextensible elements of the less wide working fabric. Said protective fabric can have an axial width less than the axial width of the less wide working fabric, and not coat, or coat, totally or partially, the coupling area between the two working crown fabrics. Said protective fabric may also have an axial width greater than the axial width of the less wide working fabric, such that it covers the edges of the working fabric "less wide and such that it is engaged, in the axial extension of the additional fabric, with the wider working crown fabric, at an axial distance, at least equal to 2% of the width S0, to be then uncoupled, axially to the outside, of the aforesaid wider working fabric, by profiles, of thickness, at least, equal to 2 mm, If necessary, the protective fabric, formed, in the aforementioned case, by elastic reinforcement elements, can be, on the one hand, uncoupled from the edges of said fabric. less broad work by profiles of thickness substantially less than the thickness of the profiles separating the edges of the two working fabrics and, on the other hand, may have an axial width less than or greater than the axial width of the widest crown fabric . Anyone that be the solution described above, it is advantageous to complete the crown reinforcement, radially inward, between the carcass reinforcement and the radially inner working fabric closest to said carcass reinforcement, by a triangulation fabric of inextensible reinforcing elements that they form with the circumferential direction an angle greater than 60 ° and in the same direction as the angle formed by the reinforcing elements of the fabric radially closer to the carcass reinforcement. Said triangulation fabric may have an axial width lower than said wider working web, which, in the considered crown reinforcement, is radially closer to the carcass reinforcement. Said triangulation web may also have an axial width greater than the width of the widest working web, and it is advantageous, then, that the fabric radially to the outside, called protective, coupled to the wider working fabric, is also coupled, in the immediate axial prolongation of the wider working fabric, to said fabric of triangulation, in an axial distance of at least 0.02 times the width S0 of the carcass reinforcement, to be then, axially to the outside, uncoupled from the edges of said triangulation fabric, by profiles, of thickness, at least, equal to 2 mm. As before, the protective fabric formed by elastic reinforcement elements can then be uncoupled from the edges of said less wide working fabric, by profiles of thickness substantially smaller than the thickness of the profiles that separate the edges of the two work fabrics. Said protective fabric may also be wider or less broad than the triangulation fabric. The work fabric radially further to the outside, can be wider axially than the working fabric radially disposed further inside: it is advantageous, then, that the crown reinforcement be completed radially to the interior by a triangulation fabric of inextensible reinforcing elements. , which form, with the circumferential direction, an angle greater than 60 ° in the same direction as the angle of the reinforcing elements of the less wide fabric (32). The so-called triangulation fabric may have an axial width less than the axial width of the working fabric which is less wide, ie radially closer to the carcass reinforcement. Preferably, said triangulation fabric will have an axial width greater than the width of the less wide working fabric and a width such that, in the axial extension of the less wide working fabric, it is coupled with the wider working fabric, at an axial distance of at least 0.02 times the width S0, to be subsequently decoupled from the edges of said fabric by means of rubber mixture profiles, of thickness, at least, equal to 2 mm, and this , be it the triangulation fabric or the widest working fabric, the one with the greatest width. The crown reinforcements just described, the work fabric being radially further away from the carcass reinforcement, axially the wider one, can also be completed, radially to the outside of said wider work fabric, by a protective fabric of elastic reinforcing elements oriented with respect to the circumferential direction an angle comprised between 10 ° and 45 °, in the same sense as the angle of the elements of the radially wider working fabric. Said protective fabric can have an axial width less than the width of the less wide working fabric, and cover, totally or partially, the coupling area between the two working crown fabrics. It can also be wider than the working fabric less broad and less wide than the wider working fabric, but preferably it will have an axial width such that it radially covers the edges of the widest working fabric, being, eventually , separated from the aforementioned edges by profiles of thickness that may be less than the thickness of the profiles that separate the edges of the less wide working fabric, from the wider working fabric, to be later, in the axial extension of the fabric of less wide work, coupled with the radially inner triangulation fabric formed by strongly inclined inextensible elements, in an axial width, at least equal to 2% of the width Ss, and then decoupled from the edges of said triangulation fabric by rubber profiles, with a thickness of at least 2 mm, either the triangulation fabric or the protective fabric, the widest DESCRIPTION OF THE FIGURES The features and advantages of the invention will be better understood with the help of the description that follows and which refers to the drawings, which illustrate, but are not limited to, exemplary embodiments, and in which: FIG. schematically represents, seen in meridian section, a first preferred variant of crown reinforcement according to the invention, figure 2 represents a second preferred variant, according to the invention, figure 3 represents, in the same way, a third variant . In Figure 1, the tire P?,, Dimension 495/45 R 22.5 X, has an H / S shape ratio equal to 0.45, where HI is the height of the tire P? on its mounting rim and S its maximum axial width. The aforementioned tire P? it comprises a radial carcass reinforcement (1) anchored in each bead, forming a fold, at least, to a rod, and formed by a single wire rope fabric. This carcass reinforcement (1) is zunchada by a crown reinforcement (3), formed radially, from the interior to the exterior, by: - a first fabric (31), called triangulation, of inextensible metallic cables oriented with respect to the direction circumferential an angle d equal to 65 °, radially above, and covering the preceding fabric called triangulation, a first working fabric (32) formed by metal cables oriented an angle a, equal, in the shown case, to 18 ° and in the same sense as the angle d of the elements of the triangulation fabric, - superimposed on the first working fabric (32), an additional fabric (33) formed by stretches or groups of stretches of inextensible metallic cables, said sections having or groups of sections, each one, a circumferential length substantially equal to 1/6 of the circumferential length of the fabric (33), and said elements being oriented to 0o, while the spaces between sections are displaced from each other, - afterwards, a second working fabric (34) formed by metal cables, identical to those of the first working fabric (32) and forming with the circumferential direction an angle ß, opposite to the angle a, in the case shown, equal to the aforementioned angle a of 18 ° (but being able to be different from the aforementioned angle a), and, finally, a last fabric of cables called elastic oriented with respect to the circumferential direction an angle,, in the same sense as the angle ß and equal to the aforementioned angle ß (but may be different from the angle cited), the latter being a protective cloth. The axial width L32 of the first working web (32) is equal to 0.87 times the maximum axial width S0 of the middle fiber of the carcass reinforcement (1), ie 416 mm, which, for a tire in the usual way, is substantially lower than the width Li of the tread, which, in the case studied, is equal to 430 mm. The axial width L3 of the second working fabric (34) is equal to 0.83 times the axial width S0, ie 400 mm. The triangulation fabric (31) has an axial width L3? intermediate between the respective widths of the two working fabrics (32, 34) and, in this case, equal to 408 mm. As for the axial width L33 of the additional fabric (33), this is equal to 320 mm. In fact, the width L33 of the additional fabric (33) is less than the width L32 (L34) of the less wide working fabric, while retaining a sufficient width to effectively contribute to the decrease of the operating temperatures of the tire in the vicinity of the ends of the working crown fabrics, which are the regions most penalized by overheating and separations between fabrics. The last crown fabric (35), called protection, has a width L35 substantially equal to 370 mm. The two working fabrics (32) and (34), on each side of the equatorial plane and axially in the extension of the additional fabric (33), are coupled in an axial width 1, equal, in this case, to 17 mm: the cables of the first work fabric (32) and the cables of the second work fabric, in the axial width 1 of coupling of the two fabrics, they are radially separated from each other by a rubber layer whose thickness is minimum and corresponds to twice the thickness of the layer of calendering rubber of the metal cables 27.23 zunched, of which each working fabric (32, 34) is formed, that is 0.8 mm. In the remaining width common to the two working fabrics, ie approximately 20 mm on each side, the two working fabrics (32) and (34) are separated by a rubber profile (4) of substantially triangular shape, the thickness of said profile (4) being increased from the axial end of the coupling area, to the end of the less wide working fabric, to reach a thickness of 4 mm at said end. Said profile (4) has a width sufficient to radially cover the end of the widest working fabric (32), which, in this case, is the working fabric radially closest to the carcass reinforcement. The crown of the tire is completed by a tread (5) joined to the heels on two sides (6), and the triangulation fabric, radially adjacent to the carcass reinforcement (1), moves away from it, in a and another part of the equatorial plane, by going axially towards the outside, said fabric being joined to the carcass reinforcement (1) by means of rubber profiles (7) of triangular shape. The tire PB, of figure 2, of dimension 315/80 R 22.5 X, has an H / S form ratio equal to 0.8, where H is the height of the tire PB on its mounting rim and S its maximum axial width . The architecture of the crown reinforcement (3) of said pneumatic tire PB differs from that previously described by the absence of the so-called triangulation fabric. Thus, the carcass reinforcement (1) anchored in each bead, forming a fold, at least, to a rod, and formed by a single wire rope fabric, is zunchada by a crown reinforcement (3), formed, radially of the interior to the outside, by: a first working crown fabric (32) formed by inextensible steel metal cables oriented at an angle a, equal, in the case shown, at 18 °, radially adjacent and parallel to the carcass reinforcement (1) ) in its middle part whose edges are separated from said carcass reinforcement by profiles "(7) of rubber thickness increasing axially from inside to outside, superimposed on the first working crown fabric(32), an additional fabric (33) formed by discontinuous non-stretchable steel metal elements of circumferential length substantially equal to 1/6 of the circumferential length of the fabric (33), said elements being oriented at 0o, the edges being separated axially outer of the first working crown fabric, of the additional fabric (33) of circumferential elements, by layers of small thickness rubber, then, a second working crown fabric (34) formed by metal wires identical to those of the first fabric (32) and forming with the circumferential direction an angle ß, opposite the angle and, in the shown case, equal to said angle a of 18 ° (but it may be different from the aforementioned angle) The axial width L32 of the first working fabric (32) is equal to 235 mm, which, for the considered tire, is slightly less than the width of the tread, which, in the case studied, is equal to 235. mm. The axial width L3 of the second working fabric (34) is slightly less than the width L32, since it is equal to 210 mm. The axial width L33 of the additional fabric (33) is equal to 176 mm. The work fabrics (32) and (34), on each side and on either side of the equatorial plane, in the extension of the additional fabric (33), are coupled at a distance 1 equal to 9 mm, which represents a slightly less than 0,03 times the maximum axial width of the carcass reinforcement (1), with the same definition of the coupling as in the previous case: minimum thickness between the fabric cables and equal, in the present case, to 1 mm . In the remaining width common to the two working fabrics, ie approximately 6 mm on each side, the two working fabrics (32) and (34) are separated by a profile (4) of triangular rubber having a thickness of 3 mm, measured at the end of the working fabric (34) less wide, the thickness of said profile being increased from the axial end of the coupling area to the end of the less wide working fabric. The crown reinforcement thus described is completed by a last fabric (35) of steel cables, called elastic, oriented with respect to the circumferential direction an angle and in the same direction as the angle 8 and equal to said angle 8 (but it can be different), -the latter fabric (35) being a protective fabric, and the cables being called elastic, cables having an elongation relative to the break, at least equal to 4%. The axial width L3s of said fabric (35) is substantially equal to 198 mm, so as to cover the coupling areas between the two working fabrics (32) and (34). The examples described and shown in figures 1 and 2 relate to a single area of coupling between fabrics. The tire shown in Figure 3, of the same dimension as that of the tire described in the first example, refers to two areas of coupling between fabrics. The architecture of the crown reinforcement (3) of the said tire Pc differs from that of the tire P? : on the one hand, by the inversion of the axial widths of the two working fabrics (32) and (34), on the other, by the modification of the widths of the working (32) and (34) and triangulation fabrics (31), the additional fabric (33) retaining the same width of 320 mm, becoming the width L32 of the radially inner working fabric (32) equal to 380 mm, becoming the width L,. of the radially outer working fabric (34) 'equal to 451 mm, so that the triangulation fabric (31) of width L3? equal to 431 mm is, on each side of the equatorial plane, coupled with the second work fabric (34), in the axial extension of the first working fabric (32), in a width 11 substantially equal to 10 mm, the edges of said triangulation fabric (31) being then decoupled from the wider working fabric ( 34) by profiles (4) of 4 mm thickness. Said preferred variant allows, in particular, to improve the resistance to separation between the edges of working fabrics at the level of the less wide fabric (32). Although it is not shown, it is easy to imagine a PD tire identical to the Pc tire described above and comprising a crown reinforcement with a protective fabric wider than the wider working fabric, that is, in the case considered, the working fabric radially further apart of the carcass reinforcement, and separated from the edges of the said work fabric by rubber mixture profiles of thickness equal to 4 mm. It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects to which it refers.

Claims (11)

1. R E I V I N D I C A C I O N S Having described the invention as above, the content of the following claims is claimed as property: 1. P tire of radial carcass reinforcement of maximum axial width s0, characterized in that it comprises a crown reinforcement formed by at least two crown fabrics of working of inextensible reinforcing elements, crossed from one fabric to another, forming with the circumferential direction angles comprised between 10 ° and 45 °, having said fabrics, axial widths L32, L34, at least, equal to 80% of the width S0 and an additional fabric of reinforcing elements substantially parallel to the circumferential direction radially disposed between said working fabrics, is characterized in that working fabrics of widths L32, L34 greater than the width L33 of the additional fabric in at least , 16% of the width S0, are, on both sides of the equatorial plane, and in the immediate axial extension of the additional fabric, coupled in an axial distance 1, at least equal to 3.5% of the width S0, to be subsequently decoupled by rubber mixing profiles, at least in the remainder of the width common to the two mentioned work fabrics. Tire according to claim 1, characterized in that the profiles have, at the ends of the less wide working fabric, a thickness at least equal to 2 mm. Tire according to claim 2, characterized in that the crown reinforcement, whose working fabrics have unequal axial widths, the working fabric being radially externally axially less wide than the working fabric positioned radially to the interior, also comprises radially to the outside, a fabric of elastic reinforcing elements, oriented with respect to the circumferential direction, an angle comprised between 10 ° and 45 ° and in the same direction as the angle formed by the inextensible elements of the less broad work fabric, having the aforementioned protective fabric an axial width L35 lower than the axial width L34 of the less wide working fabric. 4. Tire according to claim 2, characterized in that the crown reinforcement, whose working fabrics have unequal axial widths, the working fabric being radially externally less axially wide than the working fabric placed radially inwardly, also comprises radially to the outside , a fabric of elastic reinforcing elements oriented with respect to the circumferential direction an angle comprised between 10 ° and 45 ° and in the same direction as the angle formed by the inextensible elements of the less broad working fabric, said fabric having a width axial L35 such that it radially covers the edges of the less wide working fabric and, in the axial extension of the additional fabric, is coupled with the wider working crown fabric, at an axial distance, at least equal to 2 mm. % of the width So, to be then separated, axially to the outside, from said wider working web by thickness profiles, at least, equal to 2 mm. 5. Tire according to claim 4, characterized in that the protective fabric formed by elastic reinforcement elements is uncoupled from the edges of said less wide working fabric by profiles of thickness substantially less than the thickness of the profiles separating the edges of the edges. the two work fabrics. Tire according to one of claims 1 to 5, characterized in that the crown reinforcement further comprises, radially inwardly, between the carcass reinforcement and the radially inner working fabric, a fabric of inextensible reinforcement elements forming with the circumferential direction an angle greater than 60 ° in the same direction as the angle of the reinforcing elements of the working fabric, and of axial width L31 lower than the axial width L32 of the wider working fabric. 7. Tire according to claim 5, characterized in that the crown reinforcement comprisesfurthermore, radially inwardly, between the carcass reinforcement and the radially inner working web, a fabric of inextensible reinforcement elements forming with the circumferential direction an angle greater than 60 ° in the same direction as the angle of the reinforcement elements. of the working fabric, and of axial width L31 greater than the axial width of the widest working fabric, with the protective fabric, coupled to the wider working fabric, having a width L35 such that, in the immediate axial extension of the wider work fabric, is also coupled to said triangulation fabric in an axial distance 1"of at least 0.02 times the width S0 of carcass reinforcement, to be then axially to the outside, Uncoupled from the edges of said triangulation fabric by profiles of at least 2 mm thickness 8. Tire according to claim 2, characterized in that the crown reinforcement, whose work fabrics have widths uneven axially, the work fabric being radially more externally axially wider than the work fabric radially placed further inside, also comprises a fabric of inextensible reinforcing elements which form with the circumferential direction an angle greater than 60 ° of the Same as the angle of the reinforcing elements of the less wide fabric, and whose axial width L3i, is less than the width L32 of the less wide fabric. 9. Tire according to claim 2, characterized in that the crown reinforcement, whose working fabrics have unequal axial widths, the working fabric being radially more externally wider axially than the working fabric radially placed further inside, comprises, also , a triangulation fabric of inextensible reinforcing elements which, with the circumferential direction, form an angle greater than 60 ° and in the same direction as the angle of the reinforcing elements of the less wide fabric, and of axial width L3i greater than the width L32 of the less wide fabric, with the wider working fabric L34, in the immediate extension of the working fabric, coupled with the triangulation fabric in an axial distance li of at least 0.02 times the width So of carcass reinforcement (1), to be then uncoupled from the edges of said triangulation fabric by means of rubber mixing profiles, of thickness, at least, equal to 2 mm. Tire according to one of claims 8 to 9, characterized in that the crown reinforcement comprises, radially on the outside of the wider working fabric, a protective fabric of elastic reinforcing elements oriented with respect to the circumferential direction, an included angle. between 10 ° and 45 ° and in the same sense as the angle formed by the inextensible elements of the widest working fabric. 11. Tire according to claim 10, characterized in that the crown reinforcement comprises, radially to the outside of the wider working fabric, a protective fabric of elastic reinforcing elements oriented with respect to the circumferential direction an angle comprised between 10 ° and 45 ° and in the same sense as the angle formed by the inextensible elements of the wider working fabric, said fabric having an axial width L32 such that it radially covers the ends of the wider working fabric and, in the immediate extension of the fabric of less wide work, is uncoupled with the radially inner fabric 'of strongly inclined inextensible elements, in a width 12, at least equal to 2% of the width S0, and then decoupled from the edges of said triangulation fabric by profiles of rubber, of thickness, at least, equal to 2 mm.