Tyre comprising a tread having gas-drainage chamfers

Abstract

The invention relates to a tyre comprising a block (32), referred to as a draining block, the block (32) comprising: - a first longitudinal face (32a1) defining a cutout (22); - a second longitudinal face (32b1) defining another cutout (22); - an end transverse face (32c) connecting the first and second longitudinal faces to one another and defining an end cutout; - a tread surface of the tyre (162); - a moulding mark (42i1, 42i2) of a gas-discharge vent provided on the tread surface (162). The end transverse face (32c) and the tread surface (162) are connected to one another by a gas-drainage chamfer (52). The minimum distance Dmin between a contour of the moulding mark (42i1, 42i2) of the gas-discharge vent and a junction line (I, J) between the drainage chamfer (52) and the tread surface (162) is such that Dmin ≤ 5.0 mm.

Description

Tire comprising a tread including gas drainage chamfers

[0001] The present invention relates to a tire. A tire is defined as a band designed to form a cavity by cooperating with a support element, for example, a rim, this cavity being capable or not of being pressurized to a pressure greater than atmospheric pressure. A tire according to the invention has a substantially toroidal structure of revolution around a principal axis of the tire.

[0002] We know from the state of the art a four-season or all-season passenger vehicle tire described in document WO2021089964. Such a tire includes a tread intended to come into contact with the ground during rolling of the tire by means of a tread surface.

[0003] The tread comprises first and second blocks. Each first and second block extends axially from an outer axial end to an inner axial end. The outer axial end of each first block is arranged on one side of the tire's median plane, and the outer axial end of each second block is arranged on the other side of the tire's median plane. Each first and second block extends circumferentially from a circumferentially first azimuth of the inner axial end to a circumferentially second azimuth of the outer axial end. The circumferentially first azimuth enters the tire's contact patch with the road surface before the circumferentially second azimuth when the tire is mounted on a forward-moving vehicle.

[0004] Each first and second block comprises a first longitudinal face forming a leading face, a second longitudinal face forming a trailing face, and an axially internal end transverse face connecting the first and second longitudinal faces. Each block also carries a portion of the running surface.

[0005] During the tire manufacturing process, a mold is used comprising molding elements with a shape complementary to that of the tread. These elements include a molding wall for the first longitudinal face, a molding wall for the second longitudinal face, and a molding wall for the transverse end face. The mold also includes vents for releasing gases contained within the tire's constituent materials to the outside of the mold. The vents are designed to open onto a molding wall with a surface of Bearing. Despite the presence of vents, gases are particularly difficult to expel from the end gap located between the molding wall of the end cross face and the molding wall of the bearing surface. Consequently, some gases may remain trapped, resulting in unsightly molding defects that must be eliminated.

[0006] The invention therefore aims to eliminate molding defects.

[0007] To this end, the invention relates to a tire comprising a tread including at least one block, called a drainage block, comprising: - a first longitudinal face defining a longitudinal cut, - a second longitudinal face defining another longitudinal cut, - a transverse end face connecting the first and second longitudinal faces and defining an end cutout, - a portion of the tire's tread surface, - a molding mark of a gas vent formed on the part of the pneumatic running surface in which the end transverse face and the part of the running surface are connected to each other by a gas drainage chamfer, and in which the minimum distance Dmin between a contour of the molding mark of the gas vent and a junction line between the drainage chamfer and the part of the running surface is such that Dmin < 5.0 mm.

[0008] The drainage chamfer allows air to be efficiently drained from the end space to the vent, thus preventing molding defects. Indeed, the inventors of the invention understood that gases travel along the mold walls to reach the vent.During tire molding and curing, gases following the mold walls of the end cross face and the tread surface are trapped in the end gap by the tread material, which flows to fill and cross-links the end gap. By incorporating the drainage chamfer, the distance to travel between a point on the end cross face and a point on the tread area along the drainage chamfer is strictly less than the distance to travel between the same point on the end cross face and the same point on the tread area when these two faces are substantially perpendicular to each other. This reduces the time required to reach the vent and the risk of gas trapping.

[0009] The vent used in the mold can have different shapes. Preferably, a vent with a circular cross-section should be considered so that the outline of the mold mark is a circle. A vent with a curved cross-section can also be considered. or a straight line as described, for example, in DE102012104500 or EP3130439, so that the outline of the mold mark is, for example, a curved, straight, or broken line. A vent with a more complex cross-section may also be considered.

[0010] In some embodiments, the vent is formed by the junction between two consecutive circumferential molding elements of the tread. Such a junction extends across the entire axial width of the tire tread and has, for example, the shape of a curved or broken line. In these embodiments, the contour of the molding mark is a molding line of the junction.

[0011] In some embodiments, where the block is delimited by cutouts, the molding mark does not open into any of the cutouts delimiting the block. Thus, the molding mark does not serve to guide gases into the cutouts delimiting the block.

[0012] The drainage chamfer can have different configurations. For example, a straight chamfer with a flat face or a rounded chamfer with a curved surface can be used. A chamfer with multiple faces and / or surfaces is also possible.

[0013] The first and second faces are called first and second longitudinal faces because their curvilinear length is strictly greater than the curvilinear length of the transverse end face, which is therefore called the transverse face. Thus, the curvilinear length LA of the first longitudinal face, the curvilinear length LB of the second longitudinal face, and the curvilinear length LE of the transverse end face are such that LA > LE and LB > LE.

[0014] The curvilinear length of a face is the length measured along the face in question and between each end of the face in question. The curvilinear length of each first and second longitudinal face is determined from the end transverse face to an end face opposite the end transverse face. In the case of a block in which the end face opposite the end transverse face defines a cutout, the distance is measured between the end transverse face and the opposite end face. In the case of a block extending to an axial edge of the tread, the distance is measured between the end transverse face and the corresponding axial edge of the tread.

[0015] Each first and second longitudinal and transverse end face can be flat, have several flat faces, or be curved. In the case of a curved face, the face can have a variable curvature.

[0016] In the case of a straight chamfer, the line of junction between the chamfer and the part The chamfer of the rolling surface is an edge. In the case of a concave rounded chamfer, the line of junction between the chamfer and the rolling surface is an edge. In the case of a convex rounded chamfer, the line of junction between the chamfer and the rolling surface is the line along which the change in curvature becomes substantially zero when moving from the chamfer to the rolling surface.

[0017] The minimum distance Dmin is the straight-line distance measured on the bearing surface between the joint line and the contour of the air vent molding mark. Therefore, the air vent molding mark considered is implicitly the one closest to the joint line. This minimum distance Dmin ensures that gases will not be trapped in the end gap despite the presence of the chamfer.

[0018] Conventionally, the tread surface is axially delimited by first and second axial edges that coincide with the first and second axial edges of the tread, respectively. The first and second axial edges are determined on a tire mounted on a nominal rim and inflated to the nominal pressure as defined in the ETRTO 2023 standard manual. The first and second axial edges are positioned on either side of the tire's median plane and are formed by lines substantially parallel to the tire's circumferential direction. In the case of a clear boundary between the tread surface and the rest of the tire, the first and second axial edges are determined simply.In the case where the tread surface is continuous with the external surfaces of the sidewalls of the tire, the first and second axial edges are usually determined by loading the tire to 80% of its load capacity according to the ETRTO 2023 standard manual and the first and second axial edges are identified as the axial limits of the tread in contact with the ground.

[0019] A cutout on the running surface has two main characteristic dimensions: a width and a curvilinear length such that the curvilinear length is at least twice the width. A cutout is therefore delimited by at least two main lateral faces that determine its curvilinear length and are connected by a base. The two main lateral faces are separated by a non-zero distance, called the width of the cutout.

[0020] The width of a cut on a new tire is the maximum distance between the two main sidewalls, measured, by default and in the case where the cut does not include a chamfer, at a radial dimension coinciding with the tread surface, and by default and in the case where the cut includes a chamfer, at the outermost radial dimension of the cut and the innermost radial dimension of the tread. Chamfer. The width is measured substantially perpendicular to the main side faces. If a width other than the default width is specified, for example, a width at a particular dimension, the width is equal to the smallest distance between the two main side faces at the particular dimension of the cutout.

[0021] The tread depth of a cut on a new tire is the maximum radial distance between the bottom of the cut and its projection onto the ground when the tire is rolling. The maximum tread depth is called the tread depth.

[0022] The average direction of a cut is the shortest curve joining the two ends of the cut.

[0023] The general direction of a cutout is, at the radial dimension determining the width of the cutout, the direction defined by the line equidistant from the main lateral walls of the cutout.

[0024] The width of a cut or portion of a cut on a new tire is the maximum distance between the two principal sidewalls measured, by default, if the cut or portion of the cut does not include a chamfer, at a radial dimension coinciding with the tread surface, and by default, if the cut or portion of the cut includes a chamfer, at the outermost radial dimension of the cut or portion of the cut and radially inner dimension of the chamfer. The width is measured substantially perpendicular to the principal sidewalls. If a width other than the default width is specified, for example, a width at a particular dimension, the width is equal to the distance between the two principal sidewalls at that particular dimension of the cut or portion of the cut.

[0025] A cutout or a portion of a cutout can be transverse or circumferential.

[0026] A cut or cross-section is such that the cut extends along an average direction forming an angle strictly greater than 30°, preferably greater than or equal to 45°, with the circumferential direction of the tire, i.e., forming an angle less than or equal to 60°, preferably strictly less than 45°, with the axial direction of the tire. A cut or cross-section may be continuous, i.e., not interrupted by a tread block or another cut, so that the two principal lateral faces determining its length are uninterrupted along the length of the cross-section or cross-section. A cut or cross-section may also be discontinuous, i.e., interrupted by one or more tread blocks and / or one or more cuts. so that the two main lateral faces determining its length are interrupted by one or more blocks of sculpture and / or one or more cutouts.

[0027] A cut or circumferential portion is such that the cut or portion extends along an average direction forming an angle of 30° or less, preferably 10° or less, with the circumferential direction of the tire, i.e., forming an angle strictly greater than 60°, preferably strictly greater than 80°, with the axial direction of the tire. In the case of a continuous circumferential cut, the two ends coincide and are joined by a curve making a complete rotation of the tire. A cut or circumferential portion can be continuous, i.e., not interrupted by a tread block or another cut, so that the two principal lateral faces determining its length are uninterrupted over the entire circumference of the tire.A circumferential cut can also be discontinuous, that is to say interrupted by one or more blocks of tread and / or one or more cuts so that the two main lateral faces determining its length are interrupted by one or more blocks of tread and / or one or more cuts over the whole of one turn of the tire.

[0028] The tire according to the invention has a substantially toroidal shape around an axis of revolution substantially coinciding with the axis of rotation of the tire. This axis of revolution defines three directions conventionally used by those skilled in the art: an axial direction, a circumferential direction, and a radial direction.

[0029] Axial direction refers to the direction substantially parallel to the axis of revolution of the tire, that is, the axis of rotation of the tire.

[0030] By circumferential direction, we mean the direction which is substantially perpendicular to both the axial direction and to a radius of the tire (in other words, tangent to a circle whose center is on the axis of rotation of the tire).

[0031] By radial direction, we mean the direction along a radius of the tire, that is to say any direction intersecting the axis of rotation of the tire and substantially perpendicular to this axis.

[0032] By median plane of the tire (noted M), we mean the plane perpendicular to the axis of rotation of the tire which is located at mid-axial distance between the two bead ribs.

[0033] The circumferential equatorial plane of the tire (denoted E) is defined, in a meridional cross-sectional plane, as the plane passing through the tire's equator, perpendicular to the median plane and the radial direction. The tire's equator, in a meridional cross-sectional plane (a plane perpendicular to the circumferential direction and parallel to the radial and axial directions), is the axis parallel to the tire's axis of rotation and located at equidistance between the outermost radial point of the tread intended to be in contact with the ground and the innermost radial point of the tire intended to be in contact with a support, for example a rim.

[0034] By meridian plane, we mean a plane parallel to and containing the axis of rotation of the tire and perpendicular to the circumferential direction.

[0035] Radially inside and radially outside refer to the area closest to and further from the tire's axis of rotation, respectively. Axially inside and axially outside refer to the area closer to and further from the tire's median plane, respectively.

[0036] The bead is the portion of the tire designed to allow the tire to be attached to a mounting surface, such as a wheel with a rim. Each bead is specifically designed to make contact with a hook on the rim, enabling it to be secured.

[0037] Any range of values ​​designated by the expression "between a and b" represents the range of values ​​from more than a to less than b (i.e., bounds a and b excluded) while any range of values ​​designated by the expression "from a to b" means the range of values ​​from a to b (i.e., including the strict bounds a and b).

[0038] The tires of the invention are preferably intended for passenger cars or light trucks as defined in the European Tyre and Rim Technical Organisation or "ETRTO" standard, 2023. Such a tire has a cross-section in a meridian plane characterized by a section height H and a nominal section width SW as defined in the European Tyre and Rim Technical Organisation or "ETRTO" standard, 2023. The values ​​of SW and H are indicated on the tire sidewall marking, for example as defined according to the ETRTO manual, 2023.

[0039] Preferably, the passenger vehicle tires to which the invention will advantageously be applied are such that the H / S ratio, expressed as a percentage, is at most 90 and at least 20, and the nominal section width SW is at least 115 mm and at most 385 mm. Furthermore, the hook diameter D, defining the diameter of the tire mounting rim, is at least 12 inches and at most 30 inches.

[0040] In preferred and optional embodiments, the tires are referred to as all-season, all-season, or winter tires. Winter tires are specifically identified by an M+S marking (M+S being the acronym for "Mud + Snow") and / or 3PMSF (3PMSF being the acronym for "3 Peak Mountain Snow Flake"). All-season tires, due to their performance on snow, also feature M+S and / or 3PMSF markings. Unlike preferred all-season or winter tires, summer tires do not have M+S or 3PMSF markings. The tread of such all-season or winter tires includes numerous cutouts that significantly compartmentalize gases during the tire molding process. This compartmentalization reduces the number of pathways gases can take to escape. Thus, the invention is particularly useful in the case of such all-season or winter tires.

[0041] Advantageously and optionally, each first and second longitudinal face comprises one or more flat portions. Advantageously, the portion of the running surface is flat.

[0042] In preferred and optional embodiments, the longitudinal cut delimited by the first longitudinal face has a depth greater than or equal to 50%, preferably 75% and more preferably 90% of the sculpture height and a width greater than or equal to 2 mm, preferably 4 mm and more preferably 5 mm.

[0043] In preferred and optional embodiments, the other longitudinal cut delimited by the second longitudinal face has a depth greater than or equal to 50%, preferably 75% and more preferably 90% of the sculpture height and a width greater than or equal to 2 mm, preferably 4 mm and more preferably 5 mm.

[0044] In preferred and optional embodiments, the end cutout has a depth greater than or equal to 50%, preferably 75% and more preferably 90% of the carving height and a width greater than or equal to 2 mm, preferably 4 mm and more preferably 5 mm.

[0045] In preferred and optional embodiments, the gas drainage chamfer includes at least one flat face inclined relative to the transverse end face and to the portion of the tread surface. Such a drainage chamfer is relatively easy to mold and has little or no impact on tire performance.

[0046] The flat face inclined with respect to the transverse end face and with respect to the part of the rolling surface means that the normal to the flat face is not parallel to the normal to the transverse end face and not parallel to the normal to the part of the rolling surface.

[0047] In these embodiments, Dmin is the minimum distance between the contour of the molding mark of the gas vent and a junction line between the inclined flat face and the part of the running surface.

[0048] In preferred and optional embodiments, the normal to the flat face of the gas drainage chamfer forms an angle with the radial direction ranging from 20° to 70°, preferably from 30° to 60°, and more preferably from 35° to 55°. This minimizes the distance required for the gas to reach the vent and further reduces the risk of trapping gas in the end space.

[0049] In preferred and optional embodiments, Dmin < 4.0 mm, preferably Dmin < 3.0 mm, more preferably Dmin < 2.0 mm, and even more preferably Dmin < 1.0 mm. By bringing the vent closer to the chamfer, the distance that the gases must travel is further reduced, and therefore the risk of molding defects.

[0050] In preferred and optional embodiments, the curvilinear length LA of the first longitudinal face, the curvilinear length LB of the second longitudinal face, and the curvilinear length LE of the transverse end face are such that LA > 2 x LE and / or LB > 2 x LE, preferably LA > 4 x LE and / or LB > 4 x LE, and more preferably LA > 6 x LE and / or LB > 6 x LE. Such a block has a geometry that promotes gas evacuation along the first and second longitudinal faces due to their relatively large curvilinear lengths, but hinders gas evacuation along the transverse end face due to its relatively small curvilinear length. Thus, the invention is particularly useful in the case of such blocks.

[0051] In preferred and optional embodiments, the transverse end face and the first longitudinal face form an angle A such that A < 65°, preferably A < 60°, more preferably A < 55°, and even more preferably A < 50°. A relatively small angle characterizes a block with a relatively small end gap in which gases can easily become trapped. The use of a drainage chamfer is then particularly effective and allows for the efficient elimination of molding defects.

[0052] Angle A is the angle formed by the tangents to the faces in question at the point where the faces meet. In the case of two straight faces, angle A is therefore the angle formed by the two straight faces.

[0053] In preferred and optional embodiments, A > 20°, preferably A > 30°. A sufficiently large angle A makes it easier to position the vent close to the junction line.

[0054] In preferred and optional embodiments, the drainage chamfer understand : - a first flat face inclined with respect to the transverse end face and with respect to the part of the running surface, the first flat face connecting the transverse end face and the part of the running surface, the minimum distance Dmini between a contour of a first molding mark of a first gas evacuation vent and a junction line between the first flat face and the part of the running surface is such that Dmini < 5.0 mm, - a second flat face inclined with respect to the first longitudinal face and with respect to the part of the running surface, the second flat face connecting the first longitudinal face, the part of the running surface and the first flat face, the minimum distance Dminj between a contour of a second molding mark of a second gas evacuation vent and a junction line between the second flat face and the part of the running surface is such that Dminj < 5.0 mm.

[0055] Thus, thanks to the second inclined flat face, gases that might become trapped in the space between the first longitudinal face and the part of the running surface are also drained. Since the first and second faces are connected, the passage and drainage of gases along both faces is facilitated, further streamlining the drainage of gases from the end space and the space between the first longitudinal face and the part of the running surface.

[0056] In these embodiments, the first molding mark is preferably the second molding mark. Alternatively, the first and second molding marks may be different.

[0057] In optional and preferred embodiments, Dmini < 4.0 mm, more preferably Dmini < 3.0 mm, even more preferably Dmini < 2.0 mm and very preferably Dmini < 1.0 mm.

[0058] In optional and preferred embodiments, Dminj < 4.0 mm, more preferably Dminj < 3.0 mm, even more preferably Dminj < 2.0 mm and very preferably Dminj < 1.0 mm.

[0059] In advantageous and optional embodiments, the second flat face is inclined relative to the first flat face. Thus, each first and second flat face can be adapted to vent gases from the end space and the space between the first longitudinal face and the portion of the running surface.

[0060] The second flat face being inclined relative to the first flat face means that the normal to the second flat face is not parallel to the normal to the first face plane.

[0061] In optional embodiments, the second flat face forms an angle with the radial direction in an interval of 20° to 70°, preferably 30° to 60° and more preferably 35° to 55°.

[0062] In optional embodiments, particularly those used in all-season or winter tires, the block includes a secondary through-cut joining the first and second longitudinal faces. The molding mark for the air vent is located between this secondary through-cut and the end transverse face. The molding element of the secondary through-cut forms a barrier to gas evacuation from the end space, further confining the gases within that space. The drainage chamfer, combined with a vent located between the secondary through-cut and the end transverse face, prevents this gas confinement and reduces the risk of molding defects.

[0063] In optional embodiments, particularly those used in so-called 4-season, all-season or winter tires, the block includes a secondary longitudinal cut opening into the transverse end face, the tread comprising: - a first molding mark of a first air vent arranged between said secondary longitudinal cut and the first longitudinal face, the minimum distance Dmink between a contour of the first molding mark of the first gas vent and a junction line between a first drainage chamfer and the part of the running surface is such that Dmink < 5.0 mm, and - a second molding mark of a second air vent arranged between said secondary longitudinal cutout and the second longitudinal face, the minimum distance Dminl between a contour of the second molding mark of the second gas vent and a junction line between a second drainage chamfer and the part of the bearing surface is such that Dminl < 5.0 mm.

[0064] The molding element of the secondary longitudinal cut forms a separating barrier between the two portions of the block, which limits the evacuation of gases from one of the two block portions from the end space to the vent if there is only one. By arranging the first and second vents on either side of the secondary longitudinal cut, gases are drained from both portions of the block, reducing the risk of molding defects.

[0065] In these embodiments, the first drainage chamfer is preferably the second drainage chamfer. Alternatively, the first and The second drainage chamfers may be distinct.

[0066] In optional and preferred embodiments, Dmink < 4.0 mm, more preferably Dmink < 3.0 mm, even more preferably Dmink < 2.0 mm and very preferably Dmink < 1.0 mm.

[0067] In optional and preferred embodiments, Dminl < 4.0 mm, more preferably Dminl < 3.0 mm, even more preferably Dminl < 2.0 mm and very preferably Dminl < 1.0 mm.

[0068] A secondary cutout is such that each secondary cutout has a depth strictly less than the depth of at least one of the longitudinal and end cutouts or has a width strictly less than the width of at least one of the longitudinal and end cutouts.

[0069] In optional embodiments, particularly those used in so-called 4-season, all-season or winter tires, the tread comprises first and second blocks extending: - axially from an axially outer end of each first and second block to an axially inner end of each first and second block, the axially outer end of each first block being arranged on one side of the median plane of the tire, the axially outer end of each second block being arranged on the other side of the median plane of the tire, - circumferentially from a circumferentially first azimuth of the inner axial end to a circumferentially second azimuth of the outer axial end, the circumferentially first azimuth entering the contact area with the running surface of the tire before the circumferentially second azimuth when the tire is mounted on a vehicle moving forward, at least a part of the first and second blocks being one or more so-called draining block(s).

[0070] Each circumferentially first azimuth corresponds to the azimuth of the point on the axially inner end located along the circumferential direction at the midpoint of each relevant assembly. Each circumferentially second azimuth corresponds to the azimuth of the point on the axially outer end located along the circumferential direction at the midpoint of each relevant assembly.

[0071] In these embodiments, the end transverse face is the axially interior face of each first and second block.

[0072] Advantageously, the end cut is an end cut circumferential. This avoids disrupting the water flow within the circumferential end cut by eliminating molding defects. This improves the tire's wet grip performance.

[0073] Optionally, the circumferential end cut extends around the entire circumference of the tire. In one variant, the circumferential end cut extends continuously around the entire circumference of the tire. By "continuously," we mean that air can flow freely around the circumference of the tire exclusively through the circumferential end cut. In another variant, the circumferential end cut extends discontinuously around the entire circumference of the tire. In this variant, air cannot flow freely around the circumference of the tire exclusively through the circumferential end cut, for example, due to the presence of tread patterns arranged within the circumferential end cut.

[0074] In earlier versions, the circumferential end cut extends in a general direction forming a substantially constant angle with the circumferential direction of the tire. Preferably, the substantially constant angle formed by the general direction of the circumferential end cut and the circumferential direction is less than or equal to 5°, and more preferably, substantially zero. A constant angle means that the angle is the same for every azimuth of said circumferential end cut.

[0075] In second variants, the circumferential end cut extends in a general direction forming a variable angle with the circumferential direction of the tire. A variable angle means that the angle takes at least two different values ​​at at least two different azimuths of said circumferential end cut. In some variants, the general direction follows a curved line in the general shape of a sinusoid. In other variants, the general direction follows a broken line in the general shape of a zigzag.

[0076] In preferred embodiments, the tire has a direction of rotation, and the circumferentially first azimuth enters the contact patch with the tire's running surface before the circumferentially second azimuth when the tire is mounted on a vehicle moving forward and respecting its direction of rotation. In these embodiments, the tire has a predetermined direction of rotation when mounted on the vehicle. This means that the tire is designed so that, when the vehicle is moving forward, the tire rotates in a predetermined direction, called the direction of rotation. Generally, the tire The tire features markings indicating the direction of rotation. Mounting the tire in a way that does not respect the direction of rotation can result in suboptimal tire performance.

[0077] The invention also relates to a method for manufacturing a tire as defined above, in which: - A raw prototype of the tire is positioned in a mold comprising at least one gas vent designed to open onto a molding wall of the tire's tread surface, - The raw blank is cross-linked to obtain the tire so that the molding mark of the tire is the molding mark of the gas vent of the mold.

[0078] The invention will be better understood upon reading the following description, given solely by way of non-limiting example and made with reference to the drawings in which: - Figure 1 is a top view of the tread of a tire according to a first embodiment of the invention, - Figure 2 is a view of the first block of the tread shown in Figure 1. - Figure 3 is a detailed view of area III of figure 2, - Figures 4 and 5 are views analogous to those in Figures 2 and 3 of a second block of the tread in Figure 1, - Figures 6 and 7 are views, in section planes VI-VI' and VII-VII' of figure 3, of the end of the first block of figures 2 and 3, - Figures 8 and 9 are views, in section planes VI I l-VI II' and IX-IX' of figure 5, of the end of the second block of figures 4 and 5, - Figure 10 is a view similar to that of Figure 2 of a first block of a tire according to a second embodiment of the invention, - Figures 11 and 12 are views analogous respectively to those of Figures 1 and 2 of a tire according to a third embodiment, and - Figure 13 is a view similar to that of figures 2 and 12 of a tire according to a fourth embodiment.

[0079] We have represented a coordinate system X, Y, Z corresponding to the usual directions respectively axial (Y), radial (Z) and circumferential (X) of a tire.

[0080] With reference to Figure 1, the tire according to the invention is designated by the general reference numeral 10. The tire 10 has a substantially toroidal shape about an axis of revolution substantially parallel to the axial direction Y. The tire 10 is intended for a passenger vehicle and has dimensions 205 / 55R16. Tire 10 is an all-season tire. Tire 10 is shown in new condition, meaning it has not yet been driven on. Tire 10 has a rotation direction R indicating the direction in which, once mounted on the vehicle, tire 10 must rotate when the vehicle is moving forward.

[0081] The tire 10 includes a tread 14 intended to come into contact with the ground during rolling. The tire 10 also includes a conventional structure, such as, for example, described in applications WO2021250331, WO2022074341 or WO2022069819.

[0082] The tread 14 comprises a tread surface 16 through which the tread 14 is intended to come into contact with the ground when the tire 10 rolls over the ground. The tread surface 16 is axially delimited by first and second axial edges 18, 20.

[0083] The tread 14 includes first and second longitudinal cutouts 22, 24, a circumferential cutout 26 extending over the entire circumference of the tire 10. The circumferential cutout 26 extends along a general direction G forming a substantially constant angle, here substantially zero, with the circumferential direction X of the tire 10.

[0084] Each first and second longitudinal cut 22, 24 has a width greater than or equal to 2.0 mm, and here equal to 5.5 mm. The circumferential cut 26 has a width greater than or equal to 2.0 mm, and here equal to 5.0 mm. Each first and second main cut 22, 24 and the circumferential cut 26 have a depth greater than or equal to 50%, preferably 75%, and more preferably 90% of the sculpture height. Here, the sculpture height, the depth of each first and second longitudinal cut 22, 24, and the depth of the central cut 26 are approximately equal to 7.1 mm.

[0085] The tread 14 also includes first and second blocks 32, 34. Each first block 32 extends axially from an axially outer end 32A to an axially inner end 32B. The axially outer end 32A is arranged on one side of the median plane M. Similarly, each second block 34 extends axially from an axially outer end 34A to an axially inner end 34B. The axially outer end 34A is arranged on the second side of the median plane M, that is, on the opposite side from the side where the axially outer end 32A is arranged.

[0086] Each first block 32 extends circumferentially from a circumferentially first azimuth AZ1 of the axially inner end 32B to a The circumferentially second azimuth AZ2 of the outer axial end 32A. The circumferentially first azimuth AZ1 enters the contact area with the running surface of the tire 10 before the circumferentially second azimuth AZ2 when the tire 10 is mounted on a vehicle moving forward and respecting its direction of rotation R. Similarly, each second block 34 extends circumferentially from a circumferentially first azimuth AZT of the inner axial end 34B to a circumferentially second azimuth AZ2' of the outer axial end 34A. The circumferentially first azimuth AZT enters the contact area with the running surface of the tire 10 before the circumferentially second azimuth AZ2' when the tire 10 is mounted on a vehicle moving forward and respecting its direction of rotation R.

[0087] With reference to figures 1 to 5, each first block 32 comprises a first longitudinal face 32a delimiting one of the first longitudinal cutouts 22, a second longitudinal face 32b also delimiting one of the first longitudinal cutouts 22 and a transverse end face 32c delimiting an end cutout here formed by the circumferential cutout 26. The transverse end face 32c connects the first and second longitudinal faces 32a, 32b. Each first block 32 is axially delimited on the outside by the first axial edge 18. Similarly, Each second block 34 comprises a first longitudinal face 34a delimiting one of the second longitudinal cutouts 24, a second longitudinal face 34b also delimiting one of the second longitudinal cutouts 24 and a transverse end face 34c delimiting an end cutout here formed by the circumferential cutout 26.The transverse end face 34c connects the first and second longitudinal faces 34a, 34b. Each second block 34 is axially delimited on the outside by the second axial edge 20. Each transverse end face 32c, 34c is the axially interior face respectively of each first and second block 32, 34.

[0088] Each first and second block 32, 34 also includes a part 162, 164 of the running surface 16.

[0089] Each first and second block 32, 34 includes a secondary longitudinal cut 36, 38 opening respectively into each end transverse face 32c, 34c. Each secondary longitudinal cut 36, 38 has a width strictly less than the width of at least one of the longitudinal cuts 22, 24 and end cuts 26 and here equal to 1.5 mm.

[0090] Each first and second block 32, 34 comprises a plurality of mold marks 42, 44 for gas vents arranged respectively on each part of the rolling surface 162, 164. The plurality of marks 42, 44 includes first and second molding marks 42i, 42j closest to the end transverse face 32c and first and second molding marks 44i, 44j closest to the end transverse face 34c.

[0091] Each first longitudinal face 32a comprises several planar portions 32a1, 32a2, 32a3. Each second longitudinal face 32b comprises several planar portions 32b1, 32b2, 32b3. Each end transverse face 32c is planar. Similarly, each first longitudinal face 34a comprises several planar portions 34a1, 34a2, 34a3. Each second longitudinal face 34b comprises several planar portions 34b1, 34b2, 34b3. Each end transverse face 34c is planar.

[0092] Each first longitudinal face 32a, 34a has a curvilinear length LA2, LA4. Each second longitudinal face 32b, 34b has a curvilinear length LB2, LB4. Each end transverse face 32c, 34c has a curvilinear length LE2, LE4. Here, LA2 > LE2, LB2 > LE2, LA4 > LE4, LB4 > LE4, more particularly LA2 > 2 x LE2, LB2 > 2 x LE2, LA4 > 2 x LE4, LB4 > 2 x LE4, preferably LA2 > 4 x LE2, LB2 > 4 x LE2, LA4 > 4 x LE4, LB4 > 4 x LE4, and more preferably LA2 > 6 x LE2, LB2 > 6 x LE2, LA4 > 6 x LE4, LB4 > 6 x LE4. Here, LA2=LA4=100 mm, LB2=LB4=100 mm and LE2=LE4=15.6 mm.

[0093] Each end transverse face 32c, 34c and the first longitudinal face 32a, 34a, here more precisely the portion 32a1, 34a1, forms an angle A such that A < 65°, preferably A < 60°, more preferably A < 55° and even more preferably A < 50° and such that A > 20°, preferably A > 30°. Here A=35°.

[0094] Each first and second block 32, 34 includes a gas drainage chamfer 52, 54. Due to the presence of each draining chamfer 52, 54, each first and second block 32, 34 is said to be draining. Each draining chamfer 52 comprises a first flat face 52a inclined with respect to the end transverse face 32c and with respect to the portion of the running surface 162. The first flat face 52a connects the end transverse face 32c and the portion of the running surface 162. Each draining chamfer 52 comprises a second flat face 52b inclined with respect to the first longitudinal face 32a, here with respect to the portion 32a1, and with respect to the portion of the running surface 162. The second flat face 52b connects the first longitudinal face 32a, the portion of the running surface 162, and the first inclined flat face 52a. The second flat face 52b is inclined with respect to the first flat face 52a.

[0095] Similarly, each draining chamfer 54 comprises a first flat face 54a inclined with respect to the transverse end face 34c and with respect to the portion of the running surface 164. The first flat face 54a connects the end transverse face 34c and portion of the running surface 164. Each draining chamfer 54 includes a second flat face 54b inclined relative to the first longitudinal face 34a, here relative to portion 34a1, and relative to portion of the running surface 164. The second flat face 54b connects the first longitudinal face 34a, portion of the running surface 164, and the first inclined flat face 54a. The second flat face 54b is inclined relative to the first flat face 54a.

[0096] As illustrated in Figures 6 to 9, the normal to each first plane face 52a, 54a forms an angle B2, B4 respectively with the radial direction Z, within a range of 20° to 70°, preferably 30° to 60°, and more preferably 35° to 55°. Here, B2 = B4 = 45°. The normal to each second plane face 52b, 54b forms an angle C2, C4 respectively with the radial direction Z, within a range of 20° to 70°, preferably 30° to 60°, and more preferably 35° to 55°. Here, C2 = C4 = 45°.

[0097] With reference to figures 3, 5 and 6 to 9, the minimum distance Dminl between a contour, here circular in shape, of the first molding mark 42i 1 and the drainage chamfer 52, here a junction line I between the first inclined flat face 52a and the part of the rolling surface 162, is such that Dminl < 5.0 mm, preferably Dminl < 4.0 mm, more preferably Dminl < 3.0, even more preferably Dminl < 2.0 mm and very preferably Dminl < 1.0 mm.

[0098] The minimum distance Dmin2 between a contour, here circular in shape, of the first molding mark 42i1 and the drainage chamfer 52, here a junction line J between the second inclined flat face 52b and the part of the rolling surface 162, is such that Dmin2 < 5.0 mm, preferably Dmin2 < 4.0 mm, more preferably Dmin2 < 3.0, even more preferably Dmin2 < 2.0 mm and very preferably Dmin2 < 1.0 mm.

[0099] The minimum distance Dmin3 between a contour, here circular in shape, of the second molding mark 42i2 and the drainage chamfer 52, here the junction line I between the first inclined flat face 52a and the part of the rolling surface 162, is such that Dmin3 < 5.0 mm, preferably Dmin3 < 4.0 mm, more preferably Dmin3 < 3.0 mm, even more preferably Dmin3 < 2.0 mm and very preferably Dmin3 < 1.0 mm.

[0100] Similarly, with reference to Figures 4 and 5, the minimum distance Dminl between a contour, here circular in shape, of the first molding mark 44i1 and the drainage chamfer 54, here a junction line I between the first inclined flat face 54a and the part of the rolling surface 164, is such that Dminl < 5.0 mm, preferably Dminl < 4.0 mm, more preferably Dminl < 3.0, even more preferably Dminl < 2.0 mm and very preferably Dminl < 1.0 mm.

[0101] The minimum distance Dmin2 between a contour, here circular in shape, of the first molding mark 44i 1 and the drainage chamfer 54, here a junction line J between the second inclined flat face 54b and the part of the rolling surface 164, is such that Dmin2 < 5.0 mm, preferably Dmin2 < 4.0 mm, more preferably Dmin2 < 3.0, even more preferably Dmin2 < 2.0 mm and very preferably Dmin2 < 1.0 mm.

[0102] The minimum distance Dmin3 between a contour, here circular in shape, of the second molding mark 44i2 and the drainage chamfer 54, here the junction line I between the first inclined flat face 54a and the part of the rolling surface 164, is such that Dmin3 < 5.0 mm, preferably Dmin3 < 4.0 mm, more preferably Dmin3 < 3.0 mm, even more preferably Dmin3 < 2.0 mm and very preferably Dmin3 < 1.0 mm.

[0103] Each first block 32 also includes longitudinal chamfers 56a, 56b connecting respectively each first and second longitudinal face 32a, 32b here each portion 32a2, 32a3, 32b2, 32b3 and the part of the running surface 162. Each second block 34 also includes longitudinal chamfers 58a, 58b connecting respectively each first and second longitudinal face 34a, 34b here each portion 34a2, 34a3, 34b2, 34b3 and the part of the running surface 164.

[0104] We will now describe tires according to second, third and fourth embodiments of the invention with reference to figures 10 to 13. Elements analogous to those of the first embodiment are designated by identical references.

[0105] In Figure 10, for the sake of brevity, only the first block 32 is shown. The characteristics described with reference to this first block 32 apply mutatis mutandis to the second block 34 of the tire according to the second embodiment. Unlike the tire 10 according to the first embodiment, the tire according to the second embodiment illustrated in Figure 10 is such that the draining chamfer 52 comprises a single flat face 52a inclined with respect to the transverse end face 32c and with respect to the portion of the tread 162, and connects the transverse end face 32c and the portion of the tread 162.

[0106] Unlike the pneumatic tire 10 according to the first embodiment, the pneumatic tire according to the third embodiment illustrated in Figures 11 and 12 is such that that the circumferential end cut 26 extends along a general direction G forming a variable angle with the circumferential direction X of the tire 10.

[0107] Each end transverse face 32c, 34c and the first longitudinal face 32a, 34a, here more precisely the portion 32a1, 34a1, form an angle A such that A=80°.

[0108] Each first and second block 32, 34 respectively comprises several secondary through cuts 37, 39, each including a secondary through cut 37i, 39i respectively closest to the end transverse face 32c, 34c. Each secondary through cut 37i joins the first longitudinal face 32a and the second longitudinal face 32b. The molding mark 42i is arranged between the secondary through cut 37i and the end transverse face 32c. Each secondary through cut 39i joins the first longitudinal face 34a and the second longitudinal face 34b. The molding mark 44i is arranged between the secondary through cut 39i and the end transverse face 34c.

[0109] Unlike the first embodiment, each first and second block 32, 34 is devoid of a longitudinal chamfer connecting each first and second longitudinal face and the part of the rolling surface.

[0110] We will now describe a tire according to a fourth embodiment of the invention with reference to Figure 13. Elements analogous to those of the first embodiment are designated by identical reference numerals. In Figure 13, for reasons of brevity, only the first block 32 is shown. The characteristics described with reference to this first block 32 apply mutatis mutandis to the second block 34 of the tire according to the fourth embodiment.

[0111] In addition to the elements described previously with reference to Figures 1 to 9, each first block 32 of the tire according to the fourth embodiment of Figure 13 comprises first and second longitudinal faces 36a, 36b defining the secondary longitudinal cut 36. Each first block 32 comprises end transverse faces 53c1, 53c2 defining a through cut 41. The end transverse face 53c1 connects the first longitudinal face 32a and the first longitudinal face 36a. The end transverse face 53c2 connects the second longitudinal face 32b and the second longitudinal face 36b.

[0112] The end transverse face 53c and the portion of the running surface 162 are connected to each other by a gas drainage chamfer 55 comprising a flat face inclined 55a with respect to the end transverse face 53c and with respect to the portion of the running surface 162. As in previous embodiments, the minimum distance Dmin between a contour of the molding mark 42i3 of the gas vent and a junction line K between the drainage chamfer 55 and the part of the rolling surface 162 is such that Dmin < 5.0 mm, preferably Dmin < 4.0 mm, more preferably Dmin < 3.0 mm, even more preferably Dmin < 2.0 mm and very preferably Dmin < 1.0 mm.

[0113] To manufacture the tires described above, a mold is used that includes a plurality of gas vents, such as the one described, for example, in EP3308926. A raw blank of the tire 10 is placed in the mold. Within the mold, the vents are arranged to open onto a molding wall of the tread surface 16 of the tire 10. Then, the raw blank is cured, for example by heating, to obtain the tire so that the molding mark of the tire is the molding mark 42i1, 42i2, 44i1, 44i2, 42i3 of each gas vent in the mold.

[0114] The invention is not limited to the embodiments described above.

Claims

DEMANDS 1. Tire (10) comprising a tread (14) comprising at least one block (32, 34), referred to as a draining block, comprising: - a first longitudinal face (32a, 34a; 36a) delimiting a longitudinal cut (22, 24; 36), - a second longitudinal face (32b, 34b; 32a) delimiting another longitudinal cut (22, 24; 22), - a transverse end face (32c, 34c; 53c) connecting the first and second longitudinal faces and defining an end cutout (26), - a portion of the tire's rolling surface (162, 164), - a molding mark (42i1, 42i2, 44i1, 44i2; 42i3) for a gas vent formed on the part of the running surface (162, 164), characterized in that the transverse end face (32c, 34c; 53c) and the part of the running surface (162, 164) are connected to each other by a gas drainage chamfer (52, 54; 55), and in that the minimum distance Dmin between a contour of the molding mark (42i1, 42i2, 44i1, 44i2; 42i3) for the gas vent and a junction line (I, J; K) between the drainage chamfer (52, 54; 55) and the part of the running surface (162, 164) is such that Dmin < 5.0 mm.

2. Pneumatic (10) according to the preceding claim, wherein the gas drainage chamfer (52, 54; 55) comprises at least one inclined plane face (52a, 52b, 54a, 54b; 55a) with respect to the transverse end face (32c, 34c; 53c) and with respect to the part of the rolling surface (162, 164).

3. Pneumatic (10) according to any one of the preceding claims, wherein Dmin < 4.0 mm, preferably Dmin < 3.0 mm, more preferably Dmin < 2.0 mm and even more preferably Dmin < 1.0 mm.

4. Pneumatic (10) according to any one of the preceding claims, wherein the curvilinear length LA of the first longitudinal face (32a, 34a), the curvilinear length LB of the second longitudinal face (32b, 34b) and the curvilinear length LE of the transverse end face (32c, 34c; 53c) are such that LA > 2 x LE and / or LB > 2 x LE, preferably LA > 4 x LE and / or LB > 4 x LE and more preferably LA > 6 x LE and / or LB > 6 x LE.

5. Pneumatic (10) according to any one of the preceding claims, wherein the drainage chamfer (52, 54) comprises: - a first flat face (52a, 54a) inclined with respect to the end transverse face (32c, 34c) and with respect to the part of the running surface (162, 164), the first flat face (52a, 54a) connecting the end transverse face (32c, 34c) and the part of the running surface (162, 164), the minimum distance Dmini between a contour of a first molding mark (42i1, 44i1) of a first gas evacuation vent and a junction line (I) between the first flat face (52a, 54a) and the part of the running surface (162, 164) is such that Dmini < 5.0 mm, - a second flat face (52b, 54b) inclined with respect to the first longitudinal face (32a, 34a) and with respect to the part of the running surface (162, 164), the second flat face (52b, 54b) connecting the first longitudinal face (32a, 34a), the part of the running surface (162, 164) and the first flat face (52a, 54a), the minimum distance Dminj between a contour of a second molding mark (42i1, 44i1) of a second gas evacuation vent and a junction line (J) between the second flat face (52b, 54b) and the part of the running surface (162, 164) is such that Dminj < 5.0 mm.

6. Pneumatic (10) according to the preceding claim, wherein the second flat face (52b, 54b) is inclined relative to the first flat face (52a, 54a).

7. Pneumatic (10) according to any one of the preceding claims, wherein the block (32, 34) comprises a secondary through cut (37i, 39i) joining the first longitudinal face (32a, 34a) and the second longitudinal face (32b, 34b), the molding mark (42i, 44i) of the air evacuation vent being arranged between said secondary through cut (36, 38) and the transverse end face (32c, 34c).

8. Pneumatic (10) according to any one of the preceding claims, wherein the block (32, 34) comprises a secondary longitudinal cutout (36, 38) opening into the transverse end face (32c, 34c), the tread (14) comprising: - a first molding mark (42i1, 44i1) of a first air discharge vent arranged between said secondary longitudinal cutout (36, 38) and the first longitudinal face (32a, 34a), the minimum distance Dmink between a contour of the first molding mark (42i1, 44i1) of the first gas discharge vent and a junction line (I) between a first drainage chamfer (52, 54) and the part of the running surface (162, 164) is such that Dmink < 5.0 mm, and - a second molding mark (42i2, 44i2) for a second air exhaust vent arranged between said secondary longitudinal cutout (36, 38) and the second longitudinal face (32b, 34b), the minimum distance Dmini between a contour of the second molding mark (42i2, 44i2) for the second gas exhaust vent and a line of junction (I) between a second drainage chamfer (52, 54) and the part of the rolling surface (162, 164) is such that Dminl < 5.0 mm.

9. Tire (10) according to any one of the preceding claims, wherein the tread (14) comprises first and second blocks (32, 34) extending: - axially from an axially external end (32A, 34A) of each first and second block (32, 34) to an axially internal end (32B, 34B) of each first and second block (32, 34), the axially external end (32A) of each first block (32) being arranged on one side of the median plane (M) of the tire, the axially external end (34A) of each second block (34) being arranged on the other side of the median plane (M) of the tire, - circumferentially from a circumferentially first azimuth (AZ1, AZT) of the inner axial end (32B, 34B) to a circumferentially second azimuth (AZ2, AZ2') of the outer axial end (32A, 34A), the circumferentially first azimuth (AZ1, AZT) entering the contact area with the running surface of the tire before the circumferentially second azimuth (AZ2, AZ2') when the tire (10) is mounted on a vehicle moving forward, at least a part of the first and second blocks (32, 34) being one or more so-called draining block(s).

10. A method for manufacturing a tire (10) according to any one of the preceding claims, wherein: - A raw prototype of the tire is positioned in a mold comprising at least one gas vent designed to open onto a molding wall of the tire's tread surface (16), - The raw blank is cross-linked to obtain the tire (10) so that the molding mark (42i1, 42i2, 44i1, 44i2; 42i3) of the tire is the molding mark of the gas vent of the mold.

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