Method for manufacturing a pneumatic tire with a carcass on a core having reinforcements that are inclined in the sidewalls and radial under the crown

Abstract

The invention relates to a method for manufacturing a tire (1), in which a series of carcass reinforcements (21) are laid on a core (10), each carcass reinforcement (21) following a laying trajectory (T1) parallel to a central axis (X10) of the core and contained in a laying plane (P1) spaced apart from the central axis (X10), so that in the crown zone (12) of the core, each carcass reinforcement (21) follows a radial plane (PR1) containing the central axis (X10) and therefore extends parallel to the central axis (X10) in the crown (2) of the tire (1), while in orthogonal projection onto a reference plane (P0) perpendicular to the central axis (X10), this same carcass reinforcement (21) in the lateral zones (13, 14) of the core, and therefore in the sidewalls (6, 7) of the tire, makes a non-zero inclination angle (A1) with respect to the radial plane (PR1) containing the central axis (X10).

Description

[Technical Field]

[0001] The present invention belongs to the field of methods and installations intended for the manufacture of pneumatic tires. [Background technology]

[0002] An installation for forming the reinforcing structure of a tire by laying a reinforcing material on a toroidal core of a shape corresponding to the tire to be manufactured is known from WO 2006 / 051082.

[0003] This equipment advantageously allows, by means of rocker arms that alternately oscillate on the surface of the core, to lay reinforcements that are inclined along an oblique direction relative to the circumferential direction of the tire, forming a "bias ply carcass" type reinforcement, or to lay reinforcements contained in a radial plane perpendicular to the circumferential direction of the tire, forming a "radial ply carcass" type reinforcement.

[0004] As is known per se, each of these two types of reinforcement has its own advantages: in particular, radial reinforcement provides good ground contact, while bias reinforcement provides stiffness and high robustness to the sidewall of the tire.

[0005] Naturally, there is a constant demand for improving the quality, dynamic performance and service life of tires, especially for demanding applications such as motor racing. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2006 / 051082 Summary of the Invention [Problem to be solved by the invention]

[0007] For this reason, the object of the present invention is to provide a new method of tire construction that makes it possible to produce tires whose reinforcements exhibit enhanced performance aspects, and more particularly tires that combine roadholding qualities similar to or better than those provided by radial reinforcements with sidewall stiffness similar to or better than those provided by bias reinforcements, while remaining effective and easy to implement industrially. [Means for solving the problem]

[0008] These objectives are: - a preparation step (a) during which a core is prepared having an annular bearing surface, the bearing surface comprising a crown zone centered on a central axis and intended to receive components of the crown of the tire, and first lateral zones, axially on either side of the crown zone, intended to receive components of a first sidewall and a first bead of the tire, and second lateral zones intended to receive components of a second sidewall and a second bead of the tire; - then a carcass reinforcement laying step (b) during which, using a laying head, a number of reinforcements, referred to as "carcass reinforcements", are laid on the bearing surface of the core, each extending from a starting position in one of the first and second lateral zones, through the crown zone, to a finishing position in the other of the first and second lateral zones; Including, During step (b) of laying the carcass reinforcement, the laying head is configured relative to the core to describe, each time a carcass reinforcement is laid, a trajectory called the "laying trajectory", which trajectory connects the start position of the carcass reinforcement in question to the end position of the carcass reinforcement and is contained in a plane called the "laying plane", which is parallel to the central axis and spaced apart from the central axis, so that the laying trajectory follows a radial plane containing the central axis adjacent the crown zone of the core, but in orthogonal projection onto a reference plane perpendicular to the central axis, this same laying trajectory, or more generally the laying plane, forms a non-zero inclination angle with respect to the radial plane containing the central axis, in the first and second lateral zones of the core, achieved using a tire building method.

[0009] Advantageously, the method according to the invention, due to the fact that it uses a laying plane called "offset", in the sense that this laying plane is parallel to the central axis of the core but does not contain the central axis of the core, makes it possible to form carcass reinforcements that are inclined at the sidewall, i.e. not radial, and therefore not perpendicular to the circumferential direction of the tire at the sidewall, as in the case of a bias ply carcass, but on the other hand are radial at the crown of the tire, and therefore perpendicular to the circumferential direction of the tire at the crown, as in the case of a radial ply carcass.

[0010] Particularly advantageously, as will be described in more detail below, the laying step can be repeated by changing the inclination angle of the laying plane, laying a first set of carcass reinforcements at a first laying angle, and then laying a second set of reinforcements on top of the first set at a second laying angle of opposite sign to the first laying angle, so that the second set of carcass reinforcements intersect with the first set of carcass reinforcements in the lateral zones of the core, but run parallel to the first set of carcass reinforcements in the radial plane in the crown zone. In this way, a carcass, and more generally a tire, is obtained that has carcass reinforcements that intersect in the sidewalls, as in conventional bias reinforcements, and therefore has increased sidewall stiffness, but retains radial carcass reinforcements under the crown, as in conventional radial reinforcements.

[0011] The inventors have also discovered that the method according to the invention makes it possible to obtain a tire in which, at the shoulder of the tire, forming the transition between the sidewall and the crown of the tire, the carcass reinforcement gradually changes its orientation angle relative to the circumferential direction of the tire as it transitions from an inclined, and therefore non-perpendicular, orientation at the sidewall to a perpendicular orientation at the crown. However, it turns out that the gradual change in the orientation of the carcass reinforcement increases the tire's resistance to separation in the zone at the shoulder of the tire located between, on the one hand, the carcass reinforcement of the sidewall and, on the other hand, the selvedge of the crown ply covering the carcass ply at the crown of the tire, so that the reinforcements cross each other and the radial reinforcement of the carcass ply present at the crown, forming, as is known per se, a reinforcement with a triangular mesh. As a result, the invention makes it possible to reinforce tires and increase their service life.

[0012] In this respect, the fact that the laying operation is carried out on a toroidally shaped core corresponding to the final shape of the tire makes it possible to preserve in the finished, vulcanized tire the orientation angles of the carcass reinforcements, and thus the transitions between these orientation angles at the shoulders, which orientation angles and this transition are initially defined in the green tire by the laying head during step (b) of laying the carcass reinforcements. The unaltered initial positioning of the carcass reinforcements advantageously makes it possible to control the quality of the tire in a completely reproducible manner.

[0013] Further objects, features and advantages of the present invention will become more clearly apparent on reading the following description and with the aid of the accompanying drawings, which are provided purely for non-limiting illustration purposes. [Brief explanation of the drawings]

[0014] [Figure 1]1 shows the principle of arrangement of the carcass reinforcement according to the invention according to a first tilt angle in a schematic side view, projected onto a reference plane perpendicular to the central axis. This figure in particular makes clear how the tilt angle can be obtained by creating a distance between the laying plane and the central axis by tilting the laying plane or by translating and offsetting the laying plane along a direction perpendicular to the central axis. [Figure 2] 2 is a schematic exploded view showing, in one and the same plane, a portion of the crown zone and corresponding portions of the first and second lateral zones bordering the crown zone on either side of the crown zone, illustrating the principle of the arrangement according to the present invention, in which a first set of carcass reinforcements, depicted by solid lines, are laid at a first inclination angle, and a second set of carcass reinforcements, depicted by dashed lines, are laid at a second inclination angle of opposite sign to the first inclination angle. Thus, the second set of reinforcements intersect with the first set of reinforcements in the lateral zones and, therefore, ultimately, in the tire's sidewalls, while the first and second sets of reinforcements all run parallel to each other and to the central axis in the crown zone and, therefore, ultimately, in the tire's crown. Thus, the first and second sets of carcass reinforcements are perpendicular to the tire's circumferential direction in the crown zone, but not perpendicular to the circumferential direction in the lateral zones. [Figure 3] 1 shows a tire obtained with a method according to the invention in cross section in a radial plane containing the central axis; [Figure 4] 1 shows a tire building installation according to the invention in a side view, projected onto a plane perpendicular to the central axis, with its laying head arranged in a first configuration for laying a first set of carcass reinforcements onto the core at a first inclination angle, where, to make the illustration easier to read, the incremental pitch between successive carcass reinforcements is artificially large compared to the actual incremental pitch. [Figure 5] FIG. 5 is an enlarged view of the circled detail in FIG. 4. [Figure 6] FIG. 5 is a perspective overall view of the facility of FIG. 4. [Figure 7]The installation of Figures 4-6 is shown in side view in the same projection plane as Figure 4, with the laying heads arranged in a second configuration to lay a second set of carcass reinforcements on the core above the first set of carcass reinforcements at a second inclination angle. Again, to make the illustration easier to read, the incremental pitch between successive carcass reinforcements has been artificially increased compared to the actual incremental pitch. DETAILED DESCRIPTION OF THE INVENTION

[0015] The invention relates to a method for manufacturing a tire 1 and to a corresponding installation 100 .

[0016] The tire 1, which is preferably a pneumatic tire, is intended to be mounted on a wheel of a vehicle.

[0017] As is known per se and as can be seen from Figure 3, the tire 1 comprises a crown 2 having a tread 3 intended to come into contact with the ground when running, a first bead 4 and a second bead 5 for fixing the tire to a mounting support such as a rim, a first sidewall 6 connecting the crown 2 to the first bead 4, and a second sidewall 7 connecting the crown 2 to the second bead 5.

[0018] In a manner known per se, the first bead 4 will house a first bead wire 8 and the second bead 5 will house a second bead wire 9. Since each of these bead wires 8, 9 forms a substantially inextensible annular band along the circumferential direction of the tire 1, each bead wire reinforces the bead 4, 5 in which it is located and thus ensures the firmness of the fixation of the tire 1 on the rim.

[0019] The method according to the invention first comprises a preparation step (a), during which a core 10 is prepared having an annular bearing surface 11. The bearing surface 11 is centred on the central axis X10 of the core 10 and comprises, as can be seen in particular in Figure 3, a crown zone 12 intended to receive components of the crown 2 of the tire, including the tread 3, and, on either axial side of the crown zone 12, first lateral zones 13 intended to receive components of the first sidewall 6 and the first bead 4 of the tire 1, and second lateral zones 14 intended to receive components of the second sidewall 7 and the second bead 5 of the tire 1.

[0020] The core 10 is preferably made of metal.

[0021] As can be seen from Figures 4, 5, 6 and 7, the core 10 is also preferably divided into a plurality of sectors 15 that are separable from one another around the central axis X10 so that the core 10 can be removed and so that the tire 1 can be removed from the tire 1 after it has been assembled and then vulcanized on the core 10.

[0022] In reality, the central axis X10 of the core 10 corresponds to the central axis of the tire 1, and the tire 1 has a toroidal shape that exhibits substantial rotational symmetry around this central axis, and once mounted on the wheel of a vehicle, rotates around this central axis during running.

[0023] By convention and for convenience of explanation, "Axial direction" means a direction parallel to the axis in question, in this case more specifically a direction parallel to the central axis X10; "Radial direction" means a direction perpendicular to the axis, i.e., a direction intersecting the axis and forming a right angle thereto, and in this case, more specifically, a direction perpendicular to the central axis X10; "Circumferential direction" means, at the point in question, a direction contained in a plane perpendicular to the axis in question, in this case more precisely in a plane perpendicular to the central axis X10, and perpendicular to a radius connecting the axis in question to the point in question, i.e. a direction perpendicular to a radial plane passing through the point in question, or equivalently, a so-called "orthogonal" direction perpendicular to the axis in question at the point in question and perpendicular to the radial direction.

[0024] Preferably, if the tire 1 is a pneumatic tire, a layer of sealing rubber, for example based on butyl rubber, will first be laid on the core 10 in order to ensure the airtightness of the inflation chamber of the pneumatic tire.

[0025] The method according to the invention then comprises, after the preparatory step (a) and, if this is carried out, after laying a layer of sealing rubber, a step (b) of laying a carcass reinforcement, during which, using a laying head 20, a plurality of reinforcements 21, 22, referred to as "carcass reinforcements" 21, 22, are laid on the bearing surface 11 of the core 10, each extending from a starting position 21A, 22A located in one of the first and second lateral zones 13, 14, through the crown zone 12, to an ending position 21B, 22B located in the other of the first and second lateral zones 14, 13.

[0026] Preferably, the starting position 21A, 22A of each carcass reinforcement 21, 22 is located in the part of the lateral zone 13, 14 intended to receive the components of the corresponding bead 4, 5, while the ending position 21B, 22B of the carcass reinforcement 21, 22 is located in the part of the other lateral zone 14, 13 intended to receive the components of the other bead 5, 4.

[0027] More specifically, the start position 21A, 22A of each carcass reinforcement 21, 22 or the end position 21B, 22B of each carcass reinforcement 21, 22 is located in the radial area that will be covered by the bead wires 8, 9 that the lateral zones 13, 14 comprise.

[0028] Each carcass reinforcement 21, 22 therefore extends continuously to connect the first bead 4 to the opposite second bead 5, more particularly to connect the first bead wire 8 to the axially opposite second bead wire 9.

[0029] Preferably, each bead wire 8, 9 is obtained by forming, on the core at the location of the corresponding bead 4, 5, as can be seen in FIG. 3, a filamentary reinforcing element comprising one or more reinforcing threads, preferably made of metal, which extend through multiple turns, i.e., multiple complete revolutions around the central axis X10, and which thread-like reinforcing element extends continuously in the length direction of the filamentary reinforcing element.

[0030] Preferably, each carcass reinforcement 21, 22 is formed by a yarn, or more preferably by a set of yarns woven to form laces, the yarn(s) being made of a textile material.

[0031] The use of woven material advantageously makes the carcass reinforcements 21, 22 very light and also gives them a certain flexibility, which enables them to form smooth transitions at the shoulders of the tire 1 between the crown zone 12 and each of the first and second lateral zones 13, 14.

[0032] The textile material can be either a synthetic polymeric material such as polyethylene terephthalate (PET) or polyamide (e.g., Nylon®) or a natural fiber.

[0033] Alternatively, at least some or all of the carcass reinforcements 21, 22 may be made from a metallic material, preferably in the form of an integral thread.

[0034] According to further possible variants, at least part or all of the carcass reinforcements 21, 22 may each be formed from: a strip, preferably of rectangular cross section, combining a plurality of textile or metal reinforcing threads distributed parallel to one another across the width of the strip and extending over the entire length of the strip, embedded in a rubber-based substrate; or - A composite strip comprising glass fibers embedded in a resin matrix.

[0035] In any case, regardless of the nature of the carcass reinforcements 21, 22, they may be so-called "thread-like" elements, i.e., the length of which, considered from their starting position 21A, 22A to their ending position 21B, 22B, is at least 10 times, preferably at least 50 times, or even more preferably at least 100 times, the maximum transverse dimension W21, W22 of the thread-like element, considered perpendicular to the length, called the "width" W21, W22, i.e., at least 50 times, preferably at least 100 times, the maximum dimension of the carcass reinforcement cross-section.

[0036] Preferably, a layer of encapsulating rubber can also be laid on the core 10, the purpose of which is to embed the carcass reinforcements 21, 22 in this layer of encapsulating rubber, resulting in the formation of one or, if necessary, several corresponding carcass plies 23, 24, each carcass ply 23, 24 thus comprising a layer of encapsulating rubber reinforced by carcass reinforcements 21, 22 extending parallel to one another within the layer of encapsulating rubber. Since the layer of encapsulating rubber is laid on the core 10 before the carcass reinforcements 21, 22, or if necessary after this layer of encapsulating rubber, the layer of encapsulating rubber makes it possible to hold the carcass reinforcements 21, 22 on the core 10 by means of an adhesive effect while they are being laid.

[0037] According to the invention, during step (b) of laying the carcass reinforcement, the laying head 20 is configured relative to the core 10 so as to describe, each time a carcass reinforcement 21, 22 is laid, a trajectory called a "laying trajectory" T1, T2, which trajectory connects the start position 21A, 22A of said carcass reinforcement to the end position 21B, 22B of said carcass reinforcement and is contained in a plane called a "laying plane" P1, P2, which is parallel to the central axis X10 and spaced apart from the central axis. Thus, while the laying trajectories T1, T2 follow radial planes PR1, PR2 containing the central axis X10 near the crown zone 12 of the core 10, as can be seen in particular from Figures 1 and 2, in orthogonal projection onto a reference plane P0 perpendicular to the central axis X10, these same laying trajectories T1, T2, or more generally the laying planes P1, P2, in the first and second lateral zones 13, 14 of the core, form non-zero angles of inclination A1, A2 with respect to the radial planes PR1, PR2 containing the central axis X10.

[0038] Advantageously, the laying planes P1, P2 in which the carcass reinforcements 21, 22 axially cross the crown are parallel to the central axis X10 of the core, so that the carcass reinforcements 21, 22 extend parallel to the central axis X10 in the crown zone 12 of the core 10, while the laying planes P1, P2 do not contain the central axis X10 due to non-zero offset distances d1, d2 separating the central axis X10 from the laying planes P1, P2, which offset distances give the laying planes P1, P2 an inclination relative to the radial planes PR1, PR2.

[0039] The radial planes PR1, PR2, by definition, contain the central axis X10 and, by convention, pass through the radially outermost points of the laid tracks T1, T2, i.e., the points radially furthest from the central axis X10 (and therefore located in the crown zone 12 of the core 10).

[0040] Therefore, the laying planes P1, P2 and the radial planes PR1, PR2 according to the invention are not parallel to each other and consequently intersect each other.

[0041] In fact, the laying tracks T1, T2 and therefore the paths of the carcass reinforcements 21, 22 in the crown zone 12 of the core correspond to the straight lines formed by the intersection of the laying planes P1, P2 with the corresponding radial planes PR1, PR2.

[0042] Since the laying planes P1, P2 are parallel to the central axis X10 of the core 10, the portions of the laying tracks T1, T2 followed by the carcass reinforcements 21, 22 in the first lateral zone 13 overlap, when projected onto the reference plane P0, the portions of the laying tracks T1, T2 followed by these same carcass reinforcements 21, 22 in the second lateral zone 14.

[0043] Similarly, the start position 21A, 22A and end position 21B, 22B of a single carcass reinforcement are both consequently located at the same azimuth relative to the central axis X10.

[0044] According to the invention, and as can be clearly seen in FIG. 2, the laying planes P1, P2, and therefore the laying tracks T1, T2, along which the carcass reinforcements 21, 22 extend on the bearing surface 11 of the core 10, form a perpendicular angle (i.e. 90 degrees) with respect to the circumferential direction L10 of the core 10 (the angle is measured starting from the circumferential direction and ending on the laying tracks T1, T2), and therefore with respect to the circumferential direction of the tire 1, in the crown zone 12, and a complementary non-perpendicular angle with the inclination angles A1, A2 in each of the first and second lateral zones 13, 14 (i.e. in the lateral zones 13, 14, the sum of the absolute value of the inclination angles A1, A2 and the absolute value of the angle that the laying planes P1, P2 make with respect to the circumferential direction is 90 degrees).

[0045] As a guide, in the crown zone 12, the carcass reinforcements 21, 22 extend in the radial planes PR1, PR2 along straight sections parallel to the central axis X10 over a distance that corresponds to at least 30%, preferably at least 50%, or even at least 70%, and in some cases even 90% or more of the overall axial width W11 of the bearing surface 11 of the core 10 and / or over a distance that corresponds to at least 30%, preferably at least 50%, or even at least 70%, and in some cases even 90% or more of the overall axial width W1 of the tire 1 (i.e. the distance axially separating the axially outermost points of the first and second sidewalls 6, 7 of the tire 1, as can be seen in Figure 3).

[0046] For ease of explanation, it should be noted that the widths W21, W22 of the carcass reinforcements 21, 22 can be ignored in light of the overall diameter of the core 10, and as a result, the thread-like carcass reinforcements 21, 22 can be likened to lines included in the laying surfaces 21, 22.

[0047] In particular, the widths W21, W22 of the carcass reinforcement are preferably equal to or less than 2 mm, for example between 0.40 mm and 1.00 mm, for example between 0.56 mm and 0.97 mm, and may correspond to the diameter of the circular cross section inscribed by the reinforcement when the reinforcement is composed of a single thread or cord.

[0048] Preferably, the widths W21, W22 of the carcass reinforcement correspond to an angular sector occupying less than 0.5 degrees, or even less than 0.2 degrees, about the central axis X10 relative to the entire circumference of the core 10, i.e. relative to the circumference D10 of the largest diameter (typically a diameter between 610 mm and 850 mm for passenger car tyres) formed by the orthogonal projection of the core on the reference plane P0.

[0049] In any case, strictly speaking, when the widths W21, W22 of the carcass reinforcements 21, 22 are considered not to be negligible, the principles of the present invention can be applied taking into account that the trajectory called the "volume trajectory", i.e. the set of points in space described by the carcass reinforcements 21, 22 as their cross sections pass along the curves formed by the laying trajectories T1, T2, is located between two planes called "gauge planes" (parallel to the laying planes P1, P2 containing the laying trajectories T1, T2 (hence called "theoretical" laying planes), each of which is tangent to one of the selvedges of the carcass reinforcements 21, 22, and which are parallel to each other and spaced apart by the value of the widths W21, W22 of the carcass reinforcements in question, and both of which are parallel to the central axis X10), and taking into account that the central axis X10 of the core is located outside the spatial volume contained between these two gauge planes.

[0050] In other words, it ensures that: - none of the planes parallel to the theoretical laying planes P1, P2 and passing through any of the material points of the carcass reinforcements 21, 22 in question contains the central axis X10 of the core; Furthermore, one of the two gauge planes passing closest to the central axis X10 of the core remains positioned at a non-zero distance from the central axis X10 of the core, typically a distance equal to the aforementioned offset values ​​d1, d2, so as to form the desired inclination angles A1, A2 with the corresponding radial planes PR1, PR2.

[0051] Therefore, all planes parallel to the theoretical laying planes P1, P2 and passing through any one of the material points of the carcass reinforcements 21, 22, i.e. all planes parallel to the gauge planes and included between the gauge planes, will be inclined in the lateral zones 13, 14 with inclination angles A1, A2 of the same sign and value relative to each of the gauge planes.

[0052] According to a particularly preferred embodiment variant, the core 10 is mounted so that it can rotate (R_X10) about its central axis X10, and the laying head 20 is mounted so that it can tilt about an axis Y20, called the "roll axis" Y20, perpendicular to the central axis X10, so as to be able to perform laying trajectories T1, T2.

[0053] In this regard, the laying head 20 is preferably articulatable to the laying body 30 by means of a roll pivot link 31 embodying a roll axis Y20.

[0054] The roll axis Y20 is perpendicular to the selected laying planes P1, P2.

[0055] This ensures that the laying head 20 captured by the roll pivot connection 31 clearly traces out the laying trajectories T1, T2 contained in the selected laying planes P1, P2, and as a result the carcass reinforcements 21, 22 form an arcuate shape contained in the laying planes P1, P2.

[0056] As shown in Figures 4, 5, 6 and 7, the laying head 20 can be in the form of a thread-guiding rocker arm 32, in this case substantially L-shaped, which is connected to the laying body 30 by means of a roll pivot connection 31 and has a tip 32T, as a result of which the tip 32T describes a selected laying trajectory T1, T2 adjacent to the receiving surface 11 of the core 10 when the thread-guiding rocker arm 32 performs its tilting movement R_Y20 by pivoting about the roll axis Y20.

[0057] The carcass reinforcements 21, 22, more specifically the threads or cables that make up the carcass reinforcements 21, 22, are unwound during the tilting movement of the rocker arm 32 and are gradually pressed by the tip 32T of the rocker arm 32 against the receiving surface 11, in this case more specifically against a layer of rubber that has been pre-laid on the receiving surface 11, so that they follow the path of the laying tracks T1, T2 contained in the selected laying planes P1, P2.

[0058] The laying body 30 may also have a pressing member 33 intended to temporarily keep the parts of the carcass reinforcements 21, 22 located at the starting positions 21A, 22A pressed against the core 10 while the head 20 performs the tilting laying operation R_Y20.

[0059] Such a force member 33 may in particular comprise the hammer and hook system described in WO 2006 / 051082 already mentioned above.

[0060] Advantageously, the provision of a core 10 rotating about a central axis X10 and a laying head 20 mounted so that it can tilt about a roll axis Y20 makes it possible to carry out, each time a new carcass reinforcement 21, 22 is laid, a sequence, referred to as a "basic sequence", which includes: a positioning step of positioning the laying head 20 adjacent to the starting positions 21A, 22A of the carcass reinforcements 21, 22 to be laid in a predetermined angular sector of the core 10 around the central axis X10, so that, more specifically, the tip 32T of the rocker arm 32 is positioned adjacent to the parts of the lateral zones 13, 14 corresponding to the beads 4, 5, on the side of the core 10 at which it is desired to start laying the carcass reinforcements 21, 22; a laying stage, which then brings about a roll tilting R_Y20 of the laying head 20 about the roll axis Y20, while the core 10 is fixed rotatably about its central axis X10, in order to lay the carcass reinforcements 21, 22 in that angular sector along laying trajectories T1, T2 contained in selected laying planes P1, P2 parallel to and spaced from the central axis X10; - then an incremental step of causing a rotation R_X10 of the core 10 in order to advance its angular position about its central axis X10 by an incremental value, this incremental value being defined based on and preferably equal to the selected repetition pitch K1, K2 intended to distribute the carcass reinforcements 21, 22 about the central axis X10, after which the core 10 is immobilized in that angular position so that it has a new angular sector adjacent to the laying head 20 in which another carcass reinforcement 21, 22 can be laid in the next basic sequence, while maintaining the selected laying plane P1, P2.

[0061] Advantageously, such a solution makes it possible to maintain in a simple and reliable way a fixed configuration for adjusting the laying head 20 defining the laying planes P1, P2 relative to a fixed reference system of the central axis X10 of the core when transitioning from the laying of one carcass reinforcement 21, 22 to the next. Thus, from one carcass reinforcement 21, 22 to the next, the orientation of the laying planes P1, P2, and more particularly the orientation of the laying planes P1, P2 defined by their inclination angles A1, A2, is maintained without requiring a change in the setting of the roll axis Y20 or, more generally, the settings regarding the configuration of the laying head 20.

[0062] Preferably, the laying head 20, in this case the rocker arm 32, is designed to be able to move alternately around the roll axis Y20, laying one carcass reinforcement 21, 22 in a first rotational direction around the roll axis Y20 during its forward movement, and then laying the next carcass reinforcement 21, 22 in a second, opposite rotational direction around the roll axis Y20 during its return movement, etc.

[0063] Therefore, advantageously, two pressing members 33 are provided, one on each side of the core 10, adjacent the location of each bead 4,5.

[0064] Preferably, as can be seen in particular from Figures 5 and 6, successive carcass reinforcements 21, 22 laid on the core 10 in one and the same laying plane P1, P2, and therefore at one and the same tilt angle A1, A2, form one and the same integrated thread, which is successively unwound from a supply coil (not shown) and laid boustrophedonically by alternating tilting movements R_Y20 of the laying head 20, without any break in the integrated thread between one carcass reinforcement 21, 22 and the next.

[0065] The arcs formed by successive carcass reinforcements 21, 22, each spanning the crown zone 12, are therefore connected by turn-up loops 26 which extend within the zones of the beads 4, 5 from the end 21B, 22B of one carcass reinforcement 21, 22, respectively, to the start 21A, 22A of the next carcass reinforcement 21, 22. Each turn-up loop 26 therefore defines the end point of one carcass reinforcement 21, 22 and the start point of the immediately succeeding carcass reinforcement 21, 22, and therefore occupies a circumferential portion about the central axis X10 which corresponds to the desired repeat pitch K1, K2.

[0066] Advantageously, therefore, the pressing member 33 forms each turn-up loop 26 at the end of laying the carcass reinforcement 21, 22 immediately preceding the turn-up loop 26, and then helps to temporarily maintain the turn-up loop 26 during laying of the carcass reinforcement 21, 22 immediately following the turn-up loop 26.

[0067] Particularly preferably, the step (b) of laying the carcass reinforcement comprises: a first substep (b1) of laying a first set of carcass reinforcements 21, during which a first plurality of carcass reinforcements 21, referred to as "first carcass reinforcements" 21, angularly distributed around the central axis X10 with a first predetermined repetition pitch K1, are successively laid on the core 10 by means of a laying head 20 arranged in a first configuration, as can be seen in Figures 4, 5 and 6, this first configuration being parallel to the central axis X10 and at a predetermined distance therefrom, in this case a first offset distance a first sub-step (b1) of providing the laying head 20 with a first laying trajectory T1 contained in a first laying plane P1 at a distance d1, such that adjacent to the crown zone 12 of the core 10, the first laying trajectory T1 follows a radial plane PR1 containing the central axis X10, while in the first and second lateral zones 13, 14 of the core, this same first laying trajectory T1, in orthogonal projection onto a reference plane P0 perpendicular to the central axis X10, makes a first non-zero inclination angle A1 with the radial plane PR1 containing the central axis; - then a second sub-step b2 of laying a second set of carcass reinforcements 22, during which a second plurality of carcass reinforcements 22, referred to as "second carcass reinforcements" (22), angularly distributed around the central axis X10 with a second predetermined repetition pitch K2, preferably equal to the first repetition pitch, are laid successively on top of the first set of carcass reinforcements 21 on the core 10 by means of a laying head 20 configured in a second configuration, as can be seen in particular from Figure 7, this second configuration being parallel to and at a predetermined distance from the central axis X10, in this case a second sub-step b2 of providing the laying head 20 with a second laying trajectory T2 contained in a second laying plane P2 at a second offset distance d2, such that adjacent to the crown zone 12 of the core 10, the second laying trajectory T2 follows a radial plane PR2 containing the central axis X10, while in the first and second lateral zones 13, 14 of the core, this same second laying trajectory T2, in orthogonal projection onto a reference plane P0 perpendicular to the central axis X10, forms with the radial plane PR2 containing the central axis X10 a second inclination angle A2 which is non-zero and has an opposite sign to the first inclination angle A1; whereby the first carcass reinforcement 21 and the second carcass reinforcement 22 cross each other in the first lateral zone 13 and the second lateral zone 14 and thus ultimately in the sidewalls 6, 7 of the tire, while the first carcass reinforcement 21 and the second carcass reinforcement 22 run parallel to each other in a radial plane in the crown zone 12 and thus ultimately in the crown 2 of the tire 1.

[0068] As can be seen in Figure 3, advantageously, a first set of carcass reinforcements 21 are embedded in a first layer of encapsulating rubber to form a first carcass ply 23, while a second carcass reinforcement 22, which is superimposed on the first carcass ply 23, is embedded in a second layer of encapsulating rubber to form a second carcass ply 24. A so-called "carcass bi-ply" construction is thus obtained, in which the second carcass ply 24 is superimposed on the first carcass ply 23.

[0069] Advantageously, the cross arrangement of the first carcass reinforcement 21 and the second carcass reinforcement 22 makes it possible to obtain a cross laying of the crown 2 for each of the first and second beads 4, 5, as well as to form particularly robust and stiff diamond reinforcements in the sidewalls 6, 7 of the tire 1.

[0070] Preferably, as mentioned above, the first set of carcass reinforcements 21 are formed by continuous yarns shaped into juxtaposed arcs, the number of which is equal to the number of first carcass reinforcements 21 that the first set comprises, each arc being contained in a laying plane oriented at a first inclination angle A1 and connected to one another at the ends of the arcs by turn-up loops 26 located in the beads 4, 5.

[0071] Similarly, the second set of carcass reinforcements 22 are formed by continuous yarns shaped into juxtaposed arcs, the same number as the first carcass reinforcements 22 of the second set, each arc being contained in a laying plane oriented at a second inclination angle A2 and connected to each other at the ends of the arcs by turn-up loops 26 located in the beads 4, 5.

[0072] Naturally, after producing the carcass reinforcement according to the invention, the method proceeds to, as known per se, adding to the crown zone 12: a first crown ply 35 having a plurality of reinforcing threads arranged parallel to one another and forming a non-zero and non-perpendicular angle with the circumferential direction L10, so as to intersect with the crown portions of the carcass reinforcements 21, 22 lying in a radial plane; a second crown ply 36 having a plurality of reinforcing threads arranged parallel to one another and at a non-zero and non-perpendicular angle to the circumferential direction L10 so as to cross both the crown portions of the carcass reinforcements 21, 22 lying in a radial plane and the reinforcing threads of the first crown ply 35, thereby forming a triangular reinforcement mesh in the crown of the tire 1; - if necessary, a reinforcing belt 37 surrounding the crown plies 35, 36, preferably with reinforcements oriented substantially along the circumferential direction L10, said reinforcements being preferably formed in continuous bands spirally wound around the central axis X10, preferably partially overlapping each other; -Tread 3, The method may include the step of attaching

[0073] It is conceivable to use multiple laying heads 20 within the installation 100, in particular a first laying head 20 arranged in a first configuration and dedicated (exclusively) to laying a first set of carcass reinforcements 21 at a first inclination angle A1, and a second laying head 20 arranged in a second configuration and dedicated (exclusively) to laying a second set of carcass reinforcements 22 at a second inclination angle A2.

[0074] However, it is preferred to use the same laying head 20 to lay the first set of carcass reinforcements 21 and then the second set of carcass reinforcements 22 by successively transitioning the laying head 20 from its first configuration (Figures 4 to 6) used in the first sub-step (b1) of laying the first set of carcass reinforcements 21 to its second configuration (Figure 7) used in the second sub-step (b2) of laying the second set of carcass reinforcements 22.

[0075] In other words, to transition from one set of carcass reinforcements to the other, the laying head 20 is reconfigured to modify the orientation of the laying plane P1, P2, changing this orientation from the first inclination angle A1 to the second inclination angle A2.

[0076] Preferably, the step (b) of laying the carcass reinforcement comprises an adjustment sub-step (b0) during which adjustments are performed that allow the laying head 20 to be positioned in a configuration corresponding to the desired inclination angles A1, A2.

[0077] More preferably, in that case, the step (b) of laying the carcass reinforcements may comprise an adjustment sub-step (b0), during which an adjustment operation is carried out that makes it possible to transition the very same laying head 20 from a first configuration to a second configuration or vice versa, i.e., to switch between the first and second configurations or vice versa, in order to transition from laying a first set of carcass reinforcements 21 to laying a second set of carcass reinforcements.

[0078] In any case, this adjustment a translational offset component T30 according to which the laying head 20, and in this case more particularly the laying body 30, is translated linearly along a direction perpendicular to the central axis X10, or a pitch offset component R_X30 according to which the laying head 20, and in this case more particularly the laying body 30, is pivoted about an auxiliary pitch axis X30 parallel to and spaced from the central axis X10 of the core, or - a combination of the translation offset component T30 and the pitch offset component R_X30, may include:

[0079] Thus, using a simple, compact, robust and therefore precise structure, the orientation angles A1, A2 of the laying planes P1, P2 can be individually adapted by changing their offset distances d1 and d2 and / or their offset direction relative to the central axis X10.

[0080] The use of the pitch rotation adjustment component R_X30 advantageously makes it possible to increase the offset in limited spaces by avoiding the need to perform translational reversals of the laying body 30 relative to the frame of the installation 100 over excessively long distances, thus limiting the risk of mechanical interference between the laying head 20, and more particularly the laying body 30, and the rest of the structure of the installation 100.

[0081] As a guideline, the inclination angles A1, A2 of the laid tracks T1, T2 are preferably between 10 and 30 degrees in absolute value.

[0082] More specifically, when laying two sets of carcass reinforcements 21, 22 with different inclinations, each of the first inclination angle A1 and the second inclination angle A2 is preferably between 10 and 30 degrees in absolute value.

[0083] According to one possible embodiment, the second tilt angle A2 may be equal in absolute value to the first tilt angle A1, but with the opposite sign.

[0084] According to another possible embodiment, the first tilt angle A1 and the second tilt angle A2 can not only have opposite signs but also different absolute values, for example, they can be selected as follows: A1 = +10 degrees, A2 = -30 degrees.

[0085] Naturally, the invention also relates to a tire 1 obtained by the method according to the invention.

[0086] More particularly, the present invention relates to a tire 1 having a carcass with first and second carcass reinforcements 21, 22 that cross each other in the sidewalls 6, 7 of the tire 1 and are oriented parallel to each other in a radial plane in the crown 2 of the tire 1.

[0087] The invention also relates to an installation 100 for manufacturing a tire 1, said installation 100 comprising: a core 10 having an annular bearing surface 11 centered on a central axis X10 and comprising a crown zone 12 intended to receive components of the crown 2 of the tire 1, and, on either axial side of the crown zone 12, first lateral zones 13 intended to receive components of the first sidewall 6 and the first bead 4 of the tire, and second lateral zones 14 axially opposite said first lateral zone (13) intended to receive components of the second sidewall 7 and the second bead 5 of the tire; at least one laying head 20 designed to successively lay on the bearing surface 11 of the core a number of reinforcements, referred to as "carcass reinforcements" 21, 22, each extending from a starting position 21A, 22A located in the first lateral zone 13, through the crown zone 12, to an ending position 21B, 22B located in the second lateral zone 14, the laying head 20 being mounted so that it can tilt about an axis, referred to as "roll axis" Y20, perpendicular to the central axis X10; Equipped with.

[0088] This roll axis Y20 is more preferably contained in a plane called the "median plane", which is perpendicular to the central axis X10, located midway across the axial width W11 of the receiving surface 11, and preferably corresponds to the equatorial plane P_EQ of the tire 1 manufactured on the core 10.

[0089] The core 10 is mounted on a support 38 so as to be rotatable about its central axis X10.

[0090] The central axis X10 is preferably horizontal.

[0091] According to the invention, the installation 100 comprises adjustment members 40, 41 designed to tilt about a roll axis Y20 to place the laying head 20 in at least one configuration in which the roll axis Y20 is oriented so that the paths described by the laying head 20, called "laying tracks" T1, T2, are contained in planes called "laying planes" P1, P2, in order to connect the start points 21A, 22A of each carcass reinforcement 21, 22 to the end points 21B, 22B of said carcass reinforcement; Since the laying planes P1, P2 are parallel to and spaced from the central axis X10, the laying trajectories T1, T2 follow radial planes PR1, PR2 containing the central axis X10 adjacent the crown zone 12 of the core, but in orthogonal projection onto a reference plane P0 perpendicular to the central axis X10, the same laying trajectories T1, T2 have non-zero inclination angles A1, A2 with respect to the radial planes PR1, PR2 containing the central axis X10 in the first and second lateral zones 13, 14 of the core 10.

[0092] Preferably, the adjustment members 40, 41 adjust the laying head 20 to: - from a first configuration (Figures 4, 5 and 6) corresponding to a first inclination angle A1 of the laying plane P1, which allows the head 20 to lay a first set of carcass reinforcements 21 which are oriented at the first inclination angle A1 in the first and second lateral zones 13, 14 of the core 10 and on a radial plane PR1 in the crown zone 12, - to a second configuration (Figure 7) corresponding to a second inclination angle A2 of the laying plane P2 of opposite sign to the first inclination angle A1, enabling the laying head 20 to lay, on top of the first set of carcass reinforcements 21, a second set of carcass reinforcements 22 which are oriented at the second inclination angle A2 in the first and second lateral zones 13, 14 of the core 10 so as to intersect with the first set of carcass reinforcements 21, and which are oriented in a radial plane PR2 parallel to the first set of carcass reinforcements 21 in the crown zone 12 of the core 10, as shown in particular in Figure 2; It is designed to be able to transition between them.

[0093] Preferably, as can be seen from Figures 4, 6 and 7, the adjustment members 40, 41 are a translation adjustment carriage 40, which allows the laying head 20, and in this case more particularly the laying body 30, to be moved in a linear translation T30 relative to the core 10, and more generally relative to the support 38, along a direction perpendicular to the central axis X10, in this case embodied for example in a vertical direction by a vertical mast 42 provided with one or more rails that guide the carriage 40; and / or a cradle 41, which allows the laying head 20, and in this case more particularly the laying body 30, to be pitch-tilted (R_X30) about an auxiliary pitch axis X30 parallel to and spaced from the central axis X10; Equipped with.

[0094] Preferably, the cradle 41 is mounted on the carriage 40 .

[0095] Advantageously, the adjustment elements 40, 41 make it possible to reconfigure the position and orientation in space of the laying head 20, more particularly the laying body 30 and thus the laying head 20, relative to the support 38 and thus relative to the central axis X10 of the core 10, depending on the desired inclination angles A1, A2 for laying the carcass reinforcements 21, 22.

[0096] Preferably, the installation 100 comprises a control unit for automatically configuring the laying head 20, in particular depending on the set values ​​of the inclination angles A1, A2. To this end, the control unit preferably allows control of a motor, preferably an electric motor, which actuates the adjusting members 40, 41. The control unit may in particular comprise a selector for controlling the switching from the first configuration to the second configuration and vice versa.

[0097] Furthermore, the installation 100 preferably also comprises positioning members 43, 44 for positioning the laying head 20 at a desired radial position and a desired axial position relative to the central axis X10 of the core 10.

[0098] These positioning members 43, 44 can be formed by at least one horizontal translation table 43, preferably oriented perpendicular to the central axis X10, or by two crossed horizontal translation tables 43, 44, one oriented parallel to the central axis X10 to ensure axial positioning and the other oriented perpendicular to the central axis X10 to ensure radial positioning. The vertical mast 42 is preferably mounted on this translation table or, respectively, on these crossed translation tables.

[0099] These positioning members 43, 44 are preferably motor driven, preferably by electric motors, and are controlled by the control unit mentioned above.

[0100] Furthermore, the installation 100 preferably comprises a control unit (where appropriate the same as the control unit already mentioned above) equipped with a sequencer designed to automatically execute and repeat as many times as necessary a sequence, referred to as a "basic sequence", which sequence comprises: a positioning stage in which the sequencer positions the laying head 20 adjacent to the starting positions 21A, 22A of the carcass reinforcements 21, 22 to be laid in a predetermined angular sector of the core 10 around the central axis X10; a laying stage in which the sequencer induces a roll tilt (R_Y20) of the laying head 20 about the roll axis Y20, while the core 10 is rotatably fixed about its central axis X10, in order to lay the carcass reinforcements 21, 22 along laying tracks T1, T2 contained in selected laying planes P1, P2 parallel to and spaced from the central axis X10, in said angular sector; a subsequent incremental step in which the sequencer advances the angular position of the core 10 around its central axis X10 by an increment, this increment being defined based on and preferably equal to the selected repetition pitch K1, K2 intended to distribute the carcass reinforcements 21, 22 around the central axis X10, after which the sequencer freezes the core 10 in that angular position so that it has a new angular sector adjacent to the laying head 20 in which another carcass reinforcement 21, 22 can be laid in the next basic sequence, while maintaining the selected laying plane P1, P2; Includes.

[0101] Advantageously, the adjustment members 40, 41 make it possible to maintain a fixed setting of the laying body 30 relative to the central axis X10 of the installation frame and of the core, and therefore a fixed setting of the configuration of the laying head 20, throughout the laying of one set of carcass reinforcements 21, 22, while the core 10 is rotated incrementally during each process of laying a new carcass reinforcement 21, 22 by tilting the rocker arm 32.

[0102] Naturally, the invention is not limited to the variants of the embodiments described above, and the skilled person is in particular free to separate or combine any of the features described above or to replace them with equivalents.

[0103] In particular, the tire 1 obtained according to the invention can be combined with other known techniques, such as the use of studs to improve the tire's grip on ice or snow, the incorporation of foams in the tire cavity intended to reduce noise, the addition of self-sealing substances in the tire cavity that are able to automatically repair punctures, and the use of a retread tread pattern in the tread that exposes new voids that were initially hidden as the wear progresses and thus the thickness of the tread 3 decreases. [Explanation of symbols]

[0104] 10 cores 11 Annular bearing surface 12 Crown Zone 13 First Lateral Zone 21 Carcass reinforcement 21A Start position 21B End position

Claims

1. A method for manufacturing a tire (1), comprising: a preparatory step (a) during which a core (10) is provided having an annular bearing surface (11) centered on a central axis (X10) and comprising a crown zone (12) intended to receive components of the crown (2) of the tire (1), and first lateral zones (13) axially on either side of the crown zone (12) intended to receive components of the first sidewall (6) and the first bead (4) of the tire (1), and second lateral zones (14) intended to receive components of the second sidewall (7) and the second bead (5) of the tire (1); a carcass reinforcement laying step (b) during which a plurality of reinforcements (21, 22), referred to as "carcass reinforcements" (21, 22), each extending from a start position (21A, 22A) located in one of the first and second lateral zones (13, 14), through the crown zone (12) to an end position (21B, 22B) located in the other of the first and second lateral zones (14, 13), are laid on the bearing surface (11) of the core (10) using a laying head (20); Including, During the step (b) of laying the carcass reinforcement, the laying head (20) is configured relative to the core (10) so as to describe, each time it lays a carcass reinforcement (21, 22), a trajectory called a "laying trajectory" (T1, T2), which trajectory connects the start position (21A, 22A) of the carcass reinforcement in question to the end position (21B, 22B) of the carcass reinforcement in question and is contained in a plane called a "laying plane" (P1, P2), which is parallel to the central axis (X10) and spaced apart from the central axis (X10). , whereby the laying trajectories (T1, T2) follow radial planes (PR1, PR2) containing the central axis (X10) adjacent to the crown zone (12) of the core, but in orthogonal projection onto a reference plane (P0) perpendicular to the central axis (X10), the same laying trajectories (T1, T2), or more generally the laying planes (P1, P2), in the first and second lateral zones (13, 14) of the core, form non-zero inclination angles (A1, A2) with respect to the radial planes (PR1, PR2) containing the central axis (X10), A method characterized by:

2. The step (b) of laying the carcass reinforcement comprises: a first substep (b1) of laying a first set of carcass reinforcements (21), during which a first plurality of carcass reinforcements, referred to as "first carcass reinforcements" (21), angularly distributed around said central axis (X10) with a first predetermined repetition pitch (K1), are successively laid on said core using a laying head (20) configured in a first configuration, said first configuration comprising: a first laying track (T1) parallel to said central axis (X10) and contained in a first laying plane (P1) spaced apart from said central axis (X10); a first sub-step (b1) in which the first laying trajectory (T1) follows the radial plane (PR1) containing the central axis (X10) adjacent to the crown zone (12) of the core, while in orthogonal projection onto the reference plane (P0) perpendicular to the central axis (X10), the same first laying trajectory (T1) forms a first non-zero inclination angle (A1) with respect to the radial plane (PR1) containing the central axis in the first and second lateral zones (13, 14) of the core; Then, a second substep (b2) of laying a second set of carcass reinforcements (22), during which a second plurality of carcass reinforcements, referred to as "second carcass reinforcements" (22), angularly distributed around said central axis (X10) with a second predetermined repetition pitch (K2), preferably equal to said first repetition pitch (K1), are successively laid on top of said first set of carcass reinforcements (21) on said core (10) using a laying head (20) configured in a second configuration, said second configuration being laid in a second laying plane (P2) parallel to said central axis (X10) and spaced apart from said central axis (X10). a second sub-step (b2) of providing the laying head (20) with a laying trajectory (T2) so that the second laying trajectory (T2) follows a radial plane (PR2) containing the central axis (X10) adjacent to the crown zone (12) of the core, while in orthogonal projection onto the reference plane (P0) perpendicular to the central axis, the same second laying trajectory (T2) forms a second inclination angle (A2) with respect to the radial plane (PR2) containing the central axis X in the first and second lateral zones (13, 14) of the core, the second inclination angle (A2) being non-zero and having an opposite sign to the first inclination angle (A1); Including, 2. The method according to claim 1, whereby the first carcass reinforcement (21) and the second carcass reinforcement (22) cross each other in the first lateral zone (13) and the second lateral zone (14), while extending parallel to each other in a radial plane in the crown zone (12).

3. 3. The method according to claim 2, wherein the same laying head (20) is used to lay the first set of carcass reinforcements (21) and then to lay the second set of carcass reinforcements (22) by successively transitioning the laying head (20) from the first configuration used in the first sub-step (b1) of laying the first set of carcass reinforcements (21) to the second configuration used in the second sub-step (b2) of laying the second set of carcass reinforcements (22).

4. 4. The method according to claim 1, wherein the inclination angles (A1, A2) of the laid track (T1, T2), where appropriate, the first inclination angle (A1) and the second inclination angle (A2) each lie between 10 and 30 degrees in absolute value.

5. The core (10) is mounted so that it can rotate about the central axis (X10), and the laying head (20) is mounted so that it can tilt about an axis called the "roll axis" (Y20) perpendicular to the central axis (X10) so that it can carry out the laying trajectories (T1, T2), and each time a new carcass reinforcement (21, 22) is laid, positioning the laying head (20) adjacent to the starting position (21A, 22A) of the carcass reinforcement (21, 22) to be laid in a predetermined angular sector of the core (10) around the central axis (X10); a laying stage in which, in said angular sector, the laying head (20) is caused to roll tilt (R_Y20) about the roll axis (Y20) while the core (10) is rotatably fixed about the central axis (X10) in order to lay the carcass reinforcement (21, 22) along the laying track (T1, T2) included in the selected laying plane (P1, P2) parallel to and spaced apart from the central axis (X10); a subsequent incremental step of causing the rotation (R_X10) of the core (10) to advance its angular position around the central axis (X10) by an incremental value, the incremental value being defined based on, and preferably equal to, a selected repetition pitch (K1, K2) intended to distribute the carcass reinforcements (21, 22) around the central axis (X10), followed by immobilizing the core (10) in said angular position, so that the core (10) has a new angular sector adjacent to the laying head (20) in which another carcass reinforcement (21, 22) can be laid in the next basic sequence, while maintaining the selected laying plane (P1, P2); 5. The method according to claim 1, wherein a sequence called a "basic sequence" is executed, the sequence including:

6. The step (b) of laying the carcass reinforcement comprises an adjustment sub-step (b0), during which the laying head (20) is placed in the configuration corresponding to the desired inclination angles (A1, A2) and, if necessary, adjustments are made to allow the same laying head (20) to be transferred from the first configuration to the second configuration, said adjustments comprising: a translational offset component (T30) according to which the laying head (20) is translated linearly along a direction perpendicular to the central axis (X10), or a pitch offset component (R_X30) according to which the laying head (20) is pivoted about an auxiliary pitch axis (X30) parallel to and spaced from the central axis (X10) of the core, or a combination of the translation offset component (T30) and the pitch offset component (R_X30); 6. The method of claim 1, comprising:

7. 7. The method according to any one of claims 1 to 6, wherein each of the carcass reinforcements (21, 22) is formed by a yarn or, more preferably, by a set of yarns woven to form a lace, the yarn or yarns being made of a textile material.

8. 8. A tire (1) obtainable by a method according to any one of claims 1 to 7, wherein the tire (1) has a carcass comprising first carcass reinforcements (21) and second carcass reinforcements (22) which are oriented crosswise in the sidewalls (6, 7) of the tire and parallel to each other in a radial plane in the crown of the tire.

9. An installation (100) for manufacturing a tire (1), comprising: a core (10) having an annular bearing surface (11) centered on a central axis (X10) and comprising: a crown zone (12) intended to receive components of the crown (2) of the tire; first lateral zones (13) axially on either side of the crown zone (12) intended to receive components of a first sidewall (6) and a first bead (4) of the tire; and second lateral zones 14 axially opposite the first lateral zones (13) intended to receive components of a second sidewall (7) and a second bead (5) of the tire; at least one laying head (20) designed to be able to successively lay a plurality of reinforcements, called "carcass reinforcements" (21, 22), on the bearing surface (11) of the core, each of which extends from a starting position (21A, 22A) located in the first lateral zone (13), through the crown zone (12) to an ending position (21B, 22B) located in the second lateral zone (14), said laying head (20) being mounted so as to be tiltable about an axis, called the "roll axis" (Y20), perpendicular to the central axis (X10); Equipped with The installation (100) comprises adjustment members (40, 41) designed to position the laying head (20) in at least one configuration in which the roll axis (Y20) is oriented so that a path called a "laying track" (T1, T2) described by the laying head (20) is included in a plane called a "laying plane" (P1, P2), by tilting the laying head (20) about the roll axis (Y20) in order to connect the start position (21A, 22A) of each of the carcass reinforcements (21, 22) with the end position (21B, 22B) of the carcass reinforcement, and the laying plane (P1, P2) is included in the laying plane (P1, P2) of the laying head (20), and (X10) parallel to the central axis (X10) and spaced apart from the central axis (X10), so that the laying tracks (T1, T2) follow radial planes (PR1, PR2) containing the central axis (X10) adjacent the crown zone (12) of the core (10), but in orthogonal projection onto a reference plane (P0) perpendicular to the central axis (X10), the same laying tracks (T1, T2) have non-zero inclination angles (A1, A2) with respect to the radial planes (PR1, PR2) containing the central axis (X10) in the first and second lateral zones (13, 14) of the core (10).

10. The installation comprises a control unit provided with a sequencer designed to automatically execute and repeat as many times as necessary a sequence, called a "basic sequence", to cover one complete revolution of the core (10) around the central axis (X10), the basic sequence comprising: a positioning step in which the sequencer positions the laying head (20) adjacent to a starting position (21A, 22A) of a carcass reinforcement (21, 22) to be laid in a predetermined angular sector of the core (10) around the central axis (X10); a laying stage in which the sequencer induces the roll tilt (R_Y20) of the laying head (20) about the roll axis (Y20) while the core (10) is rotatably fixed about the central axis (X10) in order to lay carcass reinforcements (21, 22) in the angular sector along the laying trajectory (T1, T2) included in the selected laying plane (P1, P2) parallel to but spaced from the central axis (X10); a next incremental step in which the sequencer advances the angular position of the core (10) around the central axis (X10) by an increment, the increment being defined based on, and preferably equal to, a selected repeat pitch (K1, K2) intended to distribute the carcass reinforcements (21, 22) around the central axis, after which the sequencer fixes the core (10) in said angular position, so that the core has a new angular sector adjacent to the laying head (20) in which another carcass reinforcement (21, 22) can be laid in the next of the basic sequence, while maintaining the selected laying plane (P1, P2); The facility of claim 9, comprising:

11. 11. The installation according to claim 9 or 10, wherein the adjustment members (40, 41) comprise a translation adjustment carriage (40) that allows the laying head (20) to be moved in a linear translation (T30) relative to the core (10) along a direction perpendicular to the central axis (X10), and / or a cradle (41) that allows the laying head to be pitch-tilted (R_X30) about an auxiliary pitch axis (X30) parallel to and away from the central axis (X10).

12. The adjusting members (40, 41) are arranged from a first configuration in which the first inclination angle (A1) of the laying plane corresponds to a first configuration that enables the head (20) to lay a first set of carcass reinforcements (21) that are oriented at the first inclination angle (A1) in the first and second lateral zones (13, 14) of the core (10) and that are oriented on a radial plane in the crown zone (12) to a second inclination angle (A2) that intersects with the first set of carcass reinforcements (21) in the first and second lateral zones (13, 14) of the core (10).

12. The installation according to claim 9, wherein the installation is designed to be able to alternately transition the laying head (20) to a second configuration corresponding to a second inclination angle (A2) of the laying plane having an opposite sign to the first inclination angle (A1), which allows the laying head (20) to lay a second set of carcass reinforcements (22) on top of the first set of carcass reinforcements (21), the second set of carcass reinforcements (22) being oriented in a radial plane parallel to the first set of carcass reinforcements (21) in the crown zone (12) of the core (10).

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