Automobile tire

Abstract

A "full season" tire (1) for SUVs and crossovers is described, having a tread band (7) provided with a plurality of regular and uniformly arranged knife patterns (21, 22, 23, 24, 25, 26) and a wide central region (L1) provided with three rows of blocks, at least two of which are provided with transverse grooves only slightly inclined with respect to the direction orthogonal to the equatorial plane. The central region (L1) does not comprise a circumferential annular portion with a low void-to-rubber ratio adjacent to a central annular portion with a medium or high void-to-rubber ratio.

Description

TECHNICAL FIELD

[0001] The present application relates to a car tyre, in particular to an "all-season" tyre suitable for being fitted to SUVs and / or crossover vehicles. BACKGROUND

[0002] Some examples of car tyres are disclosed in the following documents: EP 31577764, EP 2357095, EP 1189770. SUMMARY

[0003] So-called "all-season" tyres are suitable for use in winter and summer, and are very popular and successful among users due to this particular feature, i.e. not forcing the user to own two sets of dedicated tyres, each suitable for a specific season.

[0004] To meet this requirement, tyres of this type generally need to have a very flexible behaviour, which should enable them to provide comparable performance to summer tyres in summer and comparable performance to winter tyres in winter.

[0005] The Applicant has noted that, in order to have comparable features to so-called winter tyres, "all-season" tyres should have a tread characterised by a large number of grooves or recesses and by a greater depth thereof, compared to ordinary summer tyres.

[0006] The Applicant has also noted that, similarly to winter tyres, "all-season" tyres are characterised by the presence of dense lug patterns, which increase the grip of the tyre on this type of surface, in particular when the tyre is rolling on a snow-covered road, since a small amount of snow is trapped in the lug patterns and the snow-to-snow contact increases friction.

[0007] SUVs and crossover vehicles are generally larger, stronger and heavier than saloon cars or estate cars, and generally require tyres having significant dimensions in terms of nominal section width and fitted diameter.

[0008] For example, tyres for SUVs and crossover vehicles can have a nominal section width of 275, 295 or greater, and a fitted diameter of 18 inches or greater. The use of wide tyres having a large fitted diameter gives the vehicle a sporty appearance and behaviour, and can also significantly improve driving safety on dry surfaces, in particular when cornering at high speed.

[0009] Due to the high loads to which the tyre is subjected, the large tyre size that is necessarily required in this type of application leads to a large moving mass when the tyre is rolling, and therefore to more critical tyre wear control.

[0010] Applicants have noted that, in general, in order to influence the tyre performance, it is desirable to have as much rubber on the ground as possible in the blocks of the tyre that come into contact with the ground (the footprint area), i.e. to provide blocks with a low void-to-rubber ratio. This is obviously in contrast with the requirement for "all-season" tyres to have a large number of grooves, recesses and / or sipes.

[0011] For example, in an attempt to achieve a low void-to-rubber ratio in the footprint area, it is known to provide a substantially "smooth" circumferential rib in the most central portion of the tread band, i.e. a circumferential rib substantially devoid of grooves or sipes.

[0012] However, by means of an in-depth study of the interaction between the tyre and the rolling surface, applicants have noted that the provision of a rib substantially devoid of grooves or sipes in the central portion of the tread band, adjacent to a portion of the tread band characterised by a large number of grooves and sipes, can lead to an undesirable distribution of the contact pressure in the footprint area when the tyre is rolling, triggering the phenomenon of early and / or irregular wear and thus shortening the tyre life.

[0013] Due to the general increase in collective awareness of environmental issues, the problem of wear is particularly evident at the overall level and at the level of the individual consumer / customer, who expects a certain level of durability from their products. In certain markets, such as for example the American market, it is common to require tyre manufacturers and / or distributors to guarantee a certain level of durability. It is therefore of paramount importance to develop products that reduce the occurrence of early and / or irregular wear as much as possible, in order to avoid putting products with too low a useful life on the market and / or being claimed by the end customer.

[0014] In light of the above, it is clear that "all-season" tyres, and in particular tyres for particularly heavy vehicles, such as SUVs and crossovers, should meet mutually contradictory requirements in order to provide good performance in all different road and weather conditions.

[0015] The problem faced by applicants is therefore that of providing "all-season" tyres, and in particular tyres for SUVs and crossovers, capable of ensuring a long mileage, a high level of performance, braking and traction, while not reducing the drainability, the driving safety and handling on wet ground and the driving safety on ground covered by snow.

[0016] Applicants have set themselves the task of solving this problem and have made a tyre having a tread band provided with: a plurality of regularly arranged sipes; a wide central region provided with no circumferential annular portion having a low void-to-rubber ratio arranged adjacent to a central annular portion having a medium or high void-to-rubber ratio; and three rows of blocks, of which at least two have transverse grooves only slightly inclined with respect to a direction perpendicular to the equatorial plane.

[0017] In a first aspect thereof, the present application relates to a vehicle tyre having a tread band comprising a central region extending across an equatorial plane and two shoulder regions separated from the central region by two first circumferential grooves.

[0018] The central region has at least one central rib comprising a plurality of central blocks and at least two rows of lateral blocks opposite each other with respect to said central rib and comprising a plurality of lateral blocks.

[0019] The central rib is axially delimited by two second circumferential grooves and said plurality of central blocks is delimited by a respective plurality of first curvilinear grooves.

[0020] Each first curvilinear groove extends between a second circumferential groove and a circumferentially consecutive first curvilinear groove, thus forming one of the central blocks.

[0021] The lateral blocks of each row of lateral blocks are separated from each other by means of a plurality of second curvilinear grooves, which are distributed along the entire circumferential development of the tyre and have an extension equal to at least 95% of the width of the respective row of lateral blocks.

[0022] Each of said second curvilinear grooves comprises a substantially straight first segment inclined with respect to a direction parallel to the equatorial plane of the tyre to form an angle Θ greater than or equal to 45°, a substantially straight second segment oppositely inclined with respect to the first segment, and a curvilinear connecting segment extending between the first segment and the second segment.

[0023] The tread band further comprises a plurality of sipes, including a plurality of first sipes located in the central rib between a first curvilinear groove and one of the second circumferential grooves.

[0024] The Applicant has demonstrated that the substantial absence of circumferential annular portions having a low void-to-rubber ratio in the central region reduces the variation of stiffness and contact pressure in the footprint of the tread band in the axial direction, thus limiting the occurrence of phenomena of excessive local dissipation of thermal energy due to sliding when the tyre is rolling, and makes the wear behaviour uniform, favouring long mileage.

[0025] Furthermore, the presence of sipes, in particular having a regular and uniform distribution, synergizes with the reduced variation of stiffness of the adjacent annular portions of the tread band, further improving the mileage and allowing good drainage and good behaviour on snow to be achieved.

[0026] Finally, the presence of transverse grooves, having a significant extension and only slightly inclined with respect to a direction perpendicular to the equatorial plane, allows good traction and braking characteristics to be achieved, while limiting the noise of this type of recess.

[0027] For the purposes of the present application, the following definitions apply: - "axial direction" means the direction parallel to the axis of rotation of the tyre; - "circumferential direction" means the direction parallel to the equatorial plane of the tyre; - "radial direction" means the direction perpendicular to the equatorial plane of the tyre;

[0028] "Tread pattern" means the representation of all the points of the tread band (including recesses) in a plane perpendicular to the equatorial plane of the tyre and tangent to the maximum diameter of the tyre.

[0029] The measurement of angles and / or linear quantities (distances, widths, lengths, etc.) and / or surfaces is intended to refer to the tread pattern as defined above.

[0030] Furthermore, considering the angular arrangement of the grooves, recesses and / or sipes (or segments of grooves, recesses and / or sipes) formed in the tread band with respect to the equatorial plane of the tyre, for each point of a groove, such angular arrangement is understood to refer to the acute angle (i.e. the absolute value comprised between 0° and 90°) defined by the rotation from the equatorial plane to the direction tangent to the groove, recess or sipe (or segment thereof) passing through the point. Furthermore, the angular arrangement should be understood with reference to the entire course of the groove, recess or sipe (or segment thereof). For example, in the case of a sipe or segment of sipe having a zigzag course, the angular arrangement is intended to refer to the average inclination of the sipe or segment of sipe having a zigzag course.

[0031] The term "equatorial plane" of the tyre means the plane perpendicular to the rotation axis of the tyre and dividing the tyre into two substantially equal parts.

[0032] "Circumferential" direction means the direction generally directed according to the rotation direction of the tyre, or slightly inclined (for example by at most about 20°) with respect to the rotation direction of the tyre.

[0033] "Axial" direction means the direction substantially parallel to the rotation axis of the tyre, or slightly inclined (for example by at most about 20°) with respect to the rotation axis of the tyre. Typically, the axial direction is substantially perpendicular to the circumferential direction.

[0034] The term "effective width" with reference to the tread band means the width of the radially outermost portion (from one edge to the other edge) of the tread band intended to contact the ground.

[0035] The term "groove" means a recess formed in a portion of the tread band having a width greater than or equal to 1.5 mm, and preferably a depth greater than 3 mm.

[0036] The term "sipe" means a recess formed in a portion of the tread band having a width substantially along its entire extension less than 1.5 mm, preferably less than or equal to 1 mm. Typically, at the radially outer surface of the tread band, the sipe has an extension greater than its width. Preferably, at the radially outer surface of the tread band, the sipe has an extension greater than or equal to 3 mm.

[0037] Generally speaking, the function of the sipes, in addition to the grooves, when driving on a snow-covered surface is to provide additional grip elements and to retain a certain amount of snow, thereby improving the grip on the road surface.

[0038] The width of the sipes and grooves should be measured on a new tire, at or near the radially outer surface of the tread band.

[0039] By "void-to-rubber ratio" is meant the ratio between the total surface area of the grooves in a given portion of the tread band, possibly the entire tread band, and the total surface area of the given portion, possibly the entire tread band.

[0040] In one or more preferred aspects of the application, the application can comprise one or more of the features set out hereafter.

[0041] Preferably, the second curved grooves can extend over 100% of the width of the respective row of lateral blocks.

[0042] Conveniently, the row of lateral blocks can be free of annular portions having a void-to-rubber ratio equal to zero.

[0043] Advantageously, the central rib can be free of annular portions having a void-to-rubber ratio equal to zero.

[0044] Preferably, the second section of the second curved groove can have an extension less than or equal to 1 / 3 of the extension of the first section.

[0045] Conveniently, the angle formed between the first section of the second groove and a direction parallel to the equatorial plane is comprised between 50° and 80°, preferably between 50° and 70°.

[0046] Preferably, the central rib can comprise an annular portion having a void-to-rubber ratio greater than 0.05.

[0047] Advantageously, such annular portion can be delimited in the axial direction by the second circumferential groove and one of the plurality of first curved grooves.

[0048] Conveniently, such annular portion comprises a plurality of first sipes.

[0049] Preferably, the void-to-rubber ratio of such annular portion can be generated by the first sipes only.

[0050] Advantageously, the first sipes can extend in a substantially straight line between the second circumferential groove and the first curved groove.

[0051] Conveniently, the first sipes are inclined with respect to the equatorial plane so as to form an angle greater than 45°, preferably an angle comprised between 50° and 80°, more preferably between 50° and 70°.

[0052] Preferably, the first curvilinear groove can comprise a substantially straight first section inclined with respect to a direction parallel to the equatorial plane so as to form an angle greater than 45°, preferably comprised between 50° and 80°, more preferably between 50° and 70°.

[0053] Advantageously, the first curvilinear groove comprises a curvilinear second section arranged in a substantially circumferential direction.

[0054] Preferably, the central blocks comprise a plurality of second sipes.

[0055] Conveniently, at least some of the second sipes can extend in the central blocks between one of the second circumferential grooves and the first curvilinear circumferential groove.

[0056] Advantageously, the second sipes are inclined with respect to the equatorial plane so as to form an angle greater than 45°, preferably comprised between 50° and 80°, more preferably between 50° and 70°; the second sipes can be oppositely inclined with respect to the first sipes.

[0057] Preferably, in each central block, at least some of the second sipes can comprise a central section having a zigzag course.

[0058] Conveniently, one of the rows of lateral blocks can comprise a plurality of third sipes, while another of the rows of lateral blocks can comprise a plurality of fourth sipes.

[0059] Preferably, the third sipes can extend substantially parallel to each other, even more preferably in a direction substantially parallel to the first sections of the second curvilinear grooves of the respective row of lateral blocks.

[0060] Conveniently, the fourth sipes can extend substantially parallel to each other, more preferably in a direction substantially parallel to the direction of the second sipes. Preferably, the fourth sipes can extend in a direction oppositely inclined with respect to the direction of the straight first sections of the second curvilinear grooves of the respective row of lateral blocks.

[0061] Advantageously, in each lateral block, at least some of the fourth sipes can comprise a central section having a zigzag course.

[0062] Conveniently, the second sipes, the third sipes and the fourth sipes can have a variable depth along their extension and at least one depth reduction at at least one of their ends.

[0063] Advantageously, the first shoulder region and the second shoulder region comprise a plurality of rows of shoulder blocks separated from each other by shoulder transverse grooves. Preferably, the shoulder transverse grooves have a width greater than or equal to 3 mm.

[0064] Preferably, one of the rows of shoulder blocks can comprise a plurality of fifth sipes; another of said rows of shoulder blocks can comprise a plurality of sixth sipes.

[0065] Conveniently, the fifth sipes and / or the sixth sipes can extend substantially parallel to each other, more preferably substantially parallel to the extension direction of the shoulder transverse grooves.

[0066] Preferably, the circumferentially consecutive sipes of each plurality of sipes do not have mutual intersection points and are arranged in the circumferential direction with a minimum distance greater than or equal to 6 mm.

[0067] Advantageously, the first circumferential groove and the second circumferential groove can have a width less than 15 mm, preferably less than 14 mm.

[0068] Conveniently, the first curved groove has a width greater than 2 mm.

[0069] Preferably, the first curved groove has a width less than or equal to about 5 mm, more preferably less than or equal to 4 mm.

[0070] Conveniently, the second curved groove has a width greater than 2 mm.

[0071] Preferably, the second curved groove has a width less than or equal to about 5 mm, more preferably less than or equal to 4 mm.

[0072] Preferably, the first section of the first curved groove can be substantially aligned with the first section of the second curved groove.

[0073] Conveniently, the third sipes can be oppositely inclined with respect to the fourth sipes.

[0074] Preferably, in the row of lateral blocks, the curved connecting section of the second groove connects the first section with the second section, defining a concavity oriented in a first circumferential direction, while in the remaining rows of lateral blocks, the curved connecting section connects the first section with the second section, defining a concavity oriented in a second circumferential direction opposite to said first circumferential direction.

[0075] Further features and advantages of the present application will become more apparent upon reading the detailed description which follows, with reference to some preferred but non-exclusive embodiments thereof, of a "all-season" tyre according to the present application, in particular for SUV and crossover vehicles. BRIEF DESCRIPTION OF DRAWINGS

[0076] Such a description will be made hereinafter with reference to the annexed drawings, provided purely for indicative and therefore non-limiting purposes, in which:

[0077] Figure 1 a perspective view is shown of a first example of a tyre according to the present application;

[0078] Figure 2 is an enlarged view of a cross section of the tyre of Figure 1

[0079] Figure 3 is a schematic plan view of a tread band portion of the tyre of Figure 1 DETAILED DESCRIPTION

[0080] With reference to the annexed drawings, a "all season" tyre for SUV and crossover vehicles is generally indicated by the reference number 1.

[0081] The structure of the tyre 1 is of a conventional type and comprises a carcass, a tread band 7 placed in the crown of the carcass, a pair of axially opposite sidewalls, ending with beads reinforced by a bead core and an associated bead filler. The tyre preferably also comprises a belt structure interposed between the carcass and the tread band. The carcass comprises one or more carcass plies anchored to the bead core, while the belt structure comprises two belt strips radially superimposed on each other. The belt strips are formed by pieces of fabric coated with rubber, incorporating in each strip metal cords parallel to each other and having a cross orientation with respect to the cords of the adjacent strip, preferably with a symmetrical inclination with respect to the equatorial plane. Preferably, the belt structure also comprises a third belt strip in radially outermost position, provided with cords oriented substantially parallel to the equatorial plane. Preferably, although not necessarily, the tyre according to the present application has a nominal section width of at least about 225, more preferably of at least about 245. For example, the tyre can have a nominal section width of 225, 245, 275, 295. Preferably, the tyre according to the present application has a reduced section height. For example, the section height can be less than or equal to 60% of the nominal section width, more preferably less than or equal to 50% of the nominal section width.

[0082] The tyre 1 preferably has an H / C ratio between the straight section height H and the maximum section width C comprised between 0.25 and 0.60.

[0083] In order to ensure long mileage, and at the same time high performance during the entire life of the tyre, in particular with regard to handling on wet and snow-covered ground, the tread band 7 has a total void-to-rubber ratio greater than 25%, preferably greater than 29%.

[0084] Preferably, the total void-to-rubber ratio of the tread 7 is less than 36%, more preferably less than 34%.

[0085] ​​Although not essential, preferably the tyre according to the application is of the asymmetric type, in other words the pattern of the tyre tread band 7 on the right of the equatorial plane X-X is significantly different from the pattern on the left. The tyre 1 and / or the tread band 7 thus have an inner side, arranged, when fitted, preferably towards the inside of the vehicle (on the right in the example shown in the figures) and an outer side, arranged, when fitted, preferably towards the outside of the vehicle (on the left in the example shown in the figures).

[0086] The tread band 7 is provided with four circumferential grooves extending in a substantially circumferential direction, two first circumferential grooves 2, 3 and two second circumferential grooves 4, 5 respectively. The first circumferential grooves 2 and 3 separate a central region LI of the tread band 7 from two shoulder regions L2 and L3 of the tread band 7, which are located respectively on the left and right of the central region LI.

[0087] The equatorial plane X-X of the tyre passes through the central LI region. The shoulder regions L2 and L3 extend close to the axial ends of the tread band 1.

[0088] Although not represented with a clearly identifiable edge, the end of the tread 7 can be defined by the intersection of the extension in a substantially axial direction of the radially outermost part of the tread 7 with the extension in a substantially radial direction of the axially outermost part of the tread 7.

[0089] The L2 shoulder region is located on the outer side of the tyre, while the shoulder region L3 is located on the inner side of the tyre.

[0090] The central region LI occupies a large part of the tread band 7.

[0091] In fact, the width of the central region LI can be greater than or equal to 40% of the effective width of the tread band 7, preferably greater than or equal to 50%, i.e. the width of the part of the tread band 7 intended to come into contact with the ground. In Figure 2 and Figure 3 In the example shown in the figures, this part is substantially defined by the two dotted lines passing through the axial ends of the tread band 7 itself.

[0092] The shoulder regions L2, L3 of the tread band 7 have substantially the same width.

[0093] The shoulder regions L2, L3 each have a width less than 30% of the effective width of the tread band 7. Preferably, the shoulder regions L2, L3 each have a width less than 25% of the effective width of the tread band 7.

[0094] The first circumferential groove 2 delimits a first shoulder region L2 in the axial direction with respect to the central region LI of the tread 7, while the first circumferential groove 3 delimits a second shoulder region L3 in the axial direction with respect to the central region LI.

[0095] The second grooves 4, 5 are arranged in the central region LI in order to identify the central rib 8 and the two rows 9, 10 of lateral blocks 31, 32, which will be described in more detail below.

[0096] The first 2, 3 and second 4, 5 circumferential grooves have a substantially straight course in the circumferential direction, preferably along the entire circumferential development of the tyre.

[0097] The first 2, 3 and second 4, 5 circumferential grooves are mainly responsible for draining and removing water, in particular from the central region LI of the tyre.

[0098] To this end, the first 2, 3 and second 4, 5 circumferential grooves preferably have a maximum depth comprised between about 5 mm and about 10 mm, more preferably between about 8 mm and about 10 mm.

[0099] For the same reason, the first 2, 3 and second 4, 5 circumferential grooves have a width comprised between about 8 mm and and 14 mm.

[0100] Still with reference to the embodiment shown in the figures, the first 2, 3 and second 4, 5 circumferential grooves are shaped so as to have a substantially trapezoidal direct cross section.

[0101] The central region LI is designed to maintain a high amount of rubber on the ground in the most central part of the tyre 1, i.e. near the equatorial plane X-X, while keeping the stiffness of the tread band 7 as uniform as possible in the various annular portions thereof.

[0102] To this end, the central region LI has a void-to-rubber ratio less than about 0.40, preferably less than about 0.36. Preferably, the central region LI has a void-to-rubber ratio greater than about 0.25, preferably greater than about 0.28.

[0103] The central region LI has a central rib 8 comprising a row of central blocks 30 and two rows 9, 10 of lateral blocks 31, 32 positioned opposite each other with respect to the central rib 8.

[0104] In the embodiment shown in the figures, the central rib 8 is positioned substantially across the equatorial plane X-X and is delimited in the axial direction by two second circumferential grooves 4, 5.

[0105] The central rib 8 has a plurality of central blocks 30 delimited in the circumferential direction by a first curved groove 15 and an annular portion 6 provided with a plurality of first sipes 21.

[0106] The central rib 8 therefore has no annular portion with a void-to-rubber ratio substantially equal to zero.

[0107] Each central block 30 is separated from the circumferentially successive central block 30 by a first curved groove 15.

[0108] The first curved groove 15 has a substantially straight first section 15' inclined with respect to a direction parallel to the equatorial plane X-X, and a curved second section 15" arranged in a substantially circumferential direction.

[0109] In the embodiment illustrated in the figures, the substantially straight first section 15' is inclined with respect to a direction parallel to the equatorial plane X-X so as to form an angle β greater than 45°, preferably comprised between 50° and 80°, more preferably between 50° and 70°.

[0110] Therefore, each central block 30 of the central rib 8 is delimited in the circumferential direction by two first sections 15' of two circumferentially successive first curved grooves 15, and in the axial direction by a second section 15" of the first curved groove 15 and by the second circumferential groove 5.

[0111] In Figures 1 to 3 In the embodiment illustrated, the first curved groove 15 has a constant width along its extension. Preferably, the first curved groove 15 has a width less than or equal to about 5 mm, preferably less than or equal to about 4 mm.

[0112] Preferably, the first curved groove 15 has a width greater than or equal to about 2 mm.

[0113] Preferably, the first curved groove 15 does not have a constant depth along its extension, but has a maximum depth at its central portion and at least one cross-section reduction at at least one of its ends.

[0114] Preferably, the first curved groove 15 has a maximum depth greater than about 5 mm.

[0115] Preferably, the first curved groove 15 has a maximum depth less than about 10 mm.

[0116] Preferably, the central blocks 30 of the central rib 8 have substantially the same shape.

[0117] Preferably, the central blocks 30 of the central rib 8 have a shark fin shape.

[0118] The annular portion 6 axially in side-by-side relationship with the row of central blocks 30 is delimited in the axial direction by the second circumferential groove 4 and by the second curved section 15" of the first curved groove 15.

[0119] The annular portion 6 has a void-to-rubber ratio greater than 0.05, preferably greater than 0.06.

[0120] The annular portion 6 has a void-to-rubber ratio less than 0.10.

[0121] To this end, the annular portion 6 has a plurality of first sipes 21 extending between the second circumferential groove 4 and the first curved groove 15.

[0122] The void of the annular portion 6 with rubber is created by the first 21 sipes only.

[0123] In the embodiment shown in the figures, the first sipes 21 extend axially over the entire width of the annular portion 6.

[0124] In other words, the first sipes 21 extend from the second circumferential groove 4 up to the first curved groove 15.

[0125] Preferably, the first 21 sipes have a straight course substantially along their entire extension.

[0126] The first sipes 21 extend substantially parallel to each other in the first annular portion 6.

[0127] The first sipes 21 have a minimum distance between each other in the circumferential direction greater than or equal to 6 mm.

[0128] The first sipes 21 have an inclination β' with respect to the equatorial plane X-X greater than 45°, preferably comprised between 50° and 80°, more preferably between 50° and 70°.

[0129] The first sipes 21 preferably have a maximum width less than about 1 mm.

[0130] Preferably, the first sipes 21 do not have a constant depth along their extension, but as shown better in Figure 2 they have a maximum depth at the second circumferential groove 4 and a reduced depth at the first curved groove 15.

[0131] Preferably, the first sipes 21 have a maximum depth greater than about 5 mm. The first sipes 21 have a maximum depth less than about 10 mm.

[0132] Preferably, the maximum depth of the first sipes 21 is less than the maximum depth of the circumferential grooves 2, 3, 4, 5.

[0133] In order to improve the behavior on snow, the central blocks 30 also have sipes, in particular a plurality of second sipes 22.

[0134] Some of the second sipes 22 extend from the second circumferential groove 5 to the first curved groove 15.

[0135] Preferably, in the embodiment shown in Figures 1 to 3 there are three second sipes 22 in each central block 30.

[0136] Preferably, the number of second sipes 22 in each central block 30 of the central rib 8 is constant.

[0137] Preferably, the second sipes 22 can have a straight course, not considering the short central segment 22' having a zigzag course.

[0138] The second sipes 22 have a main inclination, i.e. an inclination not considering the zigzag central segment 22', which is opposite to the inclination of the straight first segment 15' of the first curved groove 15. In detail, in the central block 30, the second sipes 22, not considering the short zigzag central segment 22', extend parallel to each other, but they are oppositely inclined with respect to the direction of the straight first segment 115' of the first curved groove 15.

[0139] With reference to Figures 1 to 3 In the illustrated embodiment, the second sipes 22 have an inclination β" with respect to the equatorial plane X-X greater than 45°, preferably comprised between 50° and 80°, more preferably between 50° and 70°.

[0140] Preferably, the second sipes 22 are oppositely inclined with respect to the first sipes 21.

[0141] The second sipes 22 have a maximum width less than about 1 mm.

[0142] Preferably, the second sipes 22 do not have a constant depth along their extension, but as illustrated in the preferred embodiment, they have a maximum depth at their central portion and at least two respective depth reductions at their ends. Figure 2 More preferably, as illustrated, they have a maximum depth at their central portion and at least two respective depth reductions at their ends.

[0143] Preferably, the second sipes 22 have a maximum depth greater than about 5 mm. Preferably, the second sipes 22 have a maximum depth less than about 10 mm.

[0144] Preferably, the maximum depth of the second sipes 22 is less than the maximum depth of the circumferential grooves 2, 3, 4, 5.

[0145] Preferably, the second sipes 22 have a minimum distance between each other in the circumferential direction greater than or equal to 6 mm.

[0146] The circumferential rows 9, 10 of lateral blocks 31, 32 are arranged axially outward with respect to the central rib 8 and are delimited by the circumferential grooves 2, 4 and 3, 5, respectively.

[0147] Each circumferential row 9, 10 has a plurality of lateral blocks 31, 32 and a plurality of second curved grooves 16. In each circumferential row 9, 10, each lateral block 31, 32 is separated from the circumferentially successive lateral blocks 31, 32 by a second curved groove 16.

[0148] Preferably, the lateral blocks 31, 32 of the circumferential rows 9, 10 have substantially the same shape, regardless of their orientation.

[0149] Each lateral block 31 of the circumferential row 9 is delimited in the circumferential direction by two second curved grooves 16 and in the axial direction by two sections of the first 2 and second 4 circumferential grooves, respectively.

[0150] Each lateral block 32 of the circumferential row 10 is delimited in the circumferential direction by two second curved grooves 16 and in the axial direction by two sections of the first 3 and second 5 circumferential grooves, respectively.

[0151] Each second curved groove 16 extends in a substantially axial direction over at least 95% of the respective row 9, 10 of lateral blocks 31, 32.

[0152] Preferably, each second transverse groove 16 extends over the entire width of the respective row block 9, 10 in which it is located.

[0153] In other words, in the circumferential row 9 of lateral blocks 31, the second curved grooves 16 are oriented in the first circumferential direction, and in the circumferential row 10 of lateral blocks 32, the second curved grooves 16 are oriented in the second circumferential direction. Figures 1 to 3 In the preferred embodiment illustrated, each second curved groove 16 extends from the axially outermost first circumferential groove 2, 3 to the axially innermost second circumferential groove 4, 5.

[0154] The choice of having through second curved grooves 16 allows to avoid the appearance of annular portions of zero void-to-rubber ratio in the circumferential rows 9, 10 of lateral blocks 31, 32, thus not creating a stiffness discontinuity within the same annular portion of the tread band 7, which would favor the tire wear.

[0155] Each second curved groove 16 has a substantially straight first section 16', a substantially straight second section 16", and a curved connecting section 16'" interposed between the substantially straight first 16' and second 16" sections.

[0156] The substantially straight second section 16" has an extension less than or equal to 1 / 3 of the extension of the substantially straight first section 16'.

[0157] The first straight section 16' has an extension greater than or equal to 50% of the width of the row of blocks 9, 10 in which it is located.

[0158] The curved connecting section 16'" is defined by a circular arc having a bending radius comprised in the range of 2 to 7 mm, preferably 4 to 6 mm.

[0159] In the circumferential row 9 of lateral blocks 31, the curved connecting section 16'" connects the substantially straight first 16' and second 16" sections, thus defining a concavity oriented in the first circumferential direction, as Figure 3The arrow P indicates the direction of the first circumferential movement. The first circumferential direction P is the same as the tire's rolling direction, as shown in the image. Figure 3 As indicated by the middle arrow F. In the circumferential row 10 of the lateral block 32, the curved connecting segment 16”' connects the substantially straight first segment 16” to the substantially straight second segment 16”, thereby defining a concavity oriented in a second circumferential direction, which is opposite to the first direction of the curved connecting segment 16”' of the second curved groove 16 of the circumferential row 9 of the lateral block 31.

[0160] Preferably, the second curved grooves 16 of the circumferential rows 9 and 10 are substantially the same, without considering the orientation of the corresponding curved connecting sections 16, and for this reason, the description of the second curved groove 16 of the circumferential row 9 will also apply to the second curved groove 16 of the circumferential row 10.

[0161] The first section 16' of the second curved groove 16 is inclined in the opposite direction to the second section 16”, which is basically straight.

[0162] Preferably, the first segment 16', which is substantially straight, is more inclined than the second segment 16".

[0163] Preferably, the straight first segment 16' forms an angle θ with the direction parallel to the equatorial plane XX, which is greater than or equal to 45°, more preferably between 50° and 80°, and even more preferably between 50° and 70°.

[0164] The second straight section 16” forms an angle θ of less than or equal to 45°, preferably less than or equal to 40°, relative to the equatorial plane XX.

[0165] exist Figures 1 to 3 In the illustrated embodiment, the second curved groove 16 has a constant width along its extension. Preferably, the second curved groove 16 has a width of less than or equal to about 5 mm, and more preferably less than or equal to 4 mm.

[0166] Preferably, the second curved groove 16 has a width greater than or equal to about 2 mm.

[0167] Preferably, the second curved groove 16 does not have a constant depth along its extension, but rather... Figure 2 More preferably, they have the maximum depth at their central portion and at least one section with a reduced cross-section at their ends.

[0168] Preferably, the second curved groove 16 has a maximum depth greater than about 5 mm.

[0169] The second curved groove 16 has a maximum depth of less than approximately 10 mm.

[0170] To improve behavior on snow, each circumferential row of blocks 9 and 10 has multiple third groove patterns 23 and fourth groove patterns 24.

[0171] The third groove pattern 23 extends axially over at least 70% of the width of the circumferential row 9 of the lateral block 31.

[0172] exist Figures 1 to 3 In the embodiment shown, there are two third groove patterns 23 in each side block 31.

[0173] Preferably, the number of third groove patterns 23 in each side block 31 of the circumferential row 9 of the side block 31 is constant.

[0174] Preferably, the third groove pattern 23 has a straight line along its entire extension.

[0175] Preferably, the third groove pattern 23 has the same inclination angle as the first groove pattern 21.

[0176] exist Figures 1 to 3 In the embodiment shown, the third groove pattern 23 is located on the extension of the first groove pattern 21.

[0177] To improve traction and braking characteristics during cornering, especially on snow-covered roads, the inclination angle of the third groove pattern 23 substantially follows the inclination angle of the straight first segment 16' of the second curved groove 16. Specifically, in the circumferential row 9 of the lateral block 31, the third groove pattern 23 extends parallel to each other and extends in a direction substantially parallel to the straight first segment 16' of the second curved groove 16.

[0178] refer to Figure 2 In the embodiment shown, the third groove pattern 23 has an angle θ' greater than 45° relative to the equatorial plane XX, preferably between 50° and 80°, and more preferably between 50° and 70°.

[0179] Preferably, the third groove pattern 23 has a maximum width of less than about 1 mm.

[0180] The third groove pattern 23 does not have a constant depth along its extension, but rather... Figures 1 to 3 More preferably, they have the maximum depth at their central portion and at their ends at at least two corresponding depth reduction portions.

[0181] Preferably, the third groove pattern 23 has a maximum depth greater than about 5 mm. Alternatively, the third groove pattern 23 may have a maximum depth less than about 10 mm.

[0182] Preferably, the maximum depth of the third groove pattern 23 is less than the maximum depth of the circumferential grooves 2, 3, 4, and 5.

[0183] Preferably, the third groove pattern 23 has a minimum distance of 6 mm or more between each other in the circumferential direction.

[0184] Still in order to improve performance on snow, the circumferential row 10 of the side block 32 has multiple fourth groove patterns 24.

[0185] The fourth groove pattern 24 extends axially over at least 70% of the width of the circumferential row 10 of the lateral block 32.

[0186] exist Figure 1 In the embodiment shown, there are three fourth groove patterns 24 in each side block 32.

[0187] Preferably, the number of fourth groove patterns 24 in each side block 32 of the circumferential row 10 of the side block 32 is constant.

[0188] Preferably, the fourth groove pattern 24 may have a straight line that runs substantially along its entire extension, excluding the short central section 24'.

[0189] exist Figure 3 , Figures 1 to 3 In the embodiment shown, each lateral block 32 of the circumferential row 10 of the lateral block 32 has three fourth blocks 24, two of which include a short central segment 24' with a zigzag route.

[0190] Still in order to improve traction and braking characteristics during cornering, especially on snow-covered roads, the principal inclination angle of the fourth groove pattern 24, i.e., the inclination angle disregarding the central section 24' with a zigzag pattern, essentially follows the inclination angle of the second groove pattern 22. More specifically, in the circumferential row 10 of the lateral block 32, the fourth groove patterns 24 are parallel to each other and extend in a direction that is inclined in the opposite direction to the direction of the straight first section 16' of the second curved groove 16, disregarding the short central section 24' with a zigzag pattern.

[0191] refer to Figure 2 In the embodiment shown, the fourth groove pattern 24 has an angle γ greater than 45° relative to the equatorial plane XX, preferably between 50° and 80°, and more preferably between 50° and 70°.

[0192] To balance the behavior of the left and right sides of the tire when driving on snow-covered roads, the fourth sipe 24 is tilted in the opposite direction to the third sipe 23.

[0193] Preferably, the fourth groove pattern 24 has a maximum width of less than about 1 mm.

[0194] The fourth groove pattern 24 does not have a constant depth along its extension; rather, it is like...Figures 1 to 3 More preferably, they have the maximum depth at their central portion and at their ends at at least two corresponding depth reduction portions.

[0195] Preferably, the fourth groove pattern 24 has a maximum depth greater than about 5 mm. Preferably, the fourth groove pattern 24 has a maximum depth less than about 10 mm.

[0196] Preferably, the maximum depth of the fourth groove pattern 24 is less than the maximum depth of the circumferential grooves 2, 3, 4, and 5.

[0197] Preferably, the fourth groove pattern 23 has a minimum distance of 6 mm or more between each other in the circumferential direction.

[0198] Referring to the shoulder regions, in order to make them more stiff than the central region L1 of the tire tread 7, the first shoulder region L2 and / or the second shoulder region L3 have a void-to-rubber ratio of less than about 0.35, preferably less than about 0.30.

[0199] Preferably, the first shoulder region L2 and the second shoulder region L3 have a void-to-rubber ratio greater than about 0.15, preferably greater than about 0.18.

[0200] To achieve this gap-to-rubber ratio, the shoulder region includes multiple shoulder transverse grooves 13, 14, and preferably includes multiple fifth groove patterns 25 and sixth groove patterns 26.

[0201] In detail, each shoulder region L2, L3 includes multiple circumferentially repeating shoulder transverse grooves 13, 14.

[0202] The shoulder transverse grooves 13 and 14 extend substantially parallel to each other in the shoulder regions L2 and L3, respectively.

[0203] Specifically, near the first circumferential grooves 2 and 3, the corresponding sections of the two circumferentially adjacent shoulder transverse grooves 13 and 14 have a mutual distance of at least about 20 mm.

[0204] The shoulder transverse grooves 13 and 14 extend axially over at least 70% of the width of the corresponding shoulder regions L2 and L3.

[0205] Preferably, the shoulder transverse grooves 13, 14 extend axially over at least 90% of the width of the respective shoulder regions L2, L3.

[0206] exist Figure 1 In the illustrated embodiment, the shoulder lateral grooves 13, 14 extend from the first end located at the corresponding edge of the tread band 7 to one of the first two circumferential grooves 2, 3.

[0207] The shoulder transverse grooves 13, 14 have a width greater than or equal to about 3 mm. Preferably, the shoulder transverse grooves 13, 14 have a width less than about 8 mm. For example, they can have a width comprised between about 3 mm and about 6 mm. In the embodiment shown, the shoulder transverse grooves 13, 14 have a constant width along their entire extension. Figure 3 , Figures 1 to 3 In the embodiment shown, the shoulder transverse grooves 14 of the inner shoulder region L3 have a constant width along substantially their entire extension, while the shoulder transverse grooves 13 of the outer shoulder region L2 have a variable width along their extension.

[0208] In particular, at the first circumferential groove 2, the shoulder transverse groove 13 has a section 13’ of reduced width.

[0209] The section 13’ of reduced width has an extension less than 30% of the width of the first shoulder region L2.

[0210] Preferably, the width of the section 13’ of reduced width is about half the width of the remaining sections of the shoulder transverse groove 13.

[0211] Each shoulder transverse groove 13, 14 has a maximum depth of at least about 3 mm, less than about 10 mm. Preferably, each shoulder transverse groove 13, 14 has a maximum depth comprised between 4 mm and 8 mm.

[0212] Preferably, each shoulder transverse groove 13, 14 has a depth which is not constant and preferably gradually decreases towards the axially outer edge of the tyre.

[0213] The shoulder transverse grooves 13, 14 extend in a direction which is transversal or slightly inclined with respect to the axial direction.

[0214] In particular, the direction of extension of the grooves 13, 14 forms, respectively with the equatorial plane X-X, an angle ω comprised between 60° and 90°, preferably between 75° and 90°.

[0215] The number of shoulder transverse grooves 13 of the shoulder region L2 is substantially equal to the number of shoulder transverse grooves 14 of the shoulder region L3.

[0216] The shoulder transverse grooves 13 of the shoulder region L2 are preferably circumferentially staggered with respect to the shoulder transverse grooves 14 of the shoulder region L3.

[0217] In order to improve the behaviour on snow, each shoulder region has a plurality of fifth sipe 25 and sixth sipe 26. In detail, the shoulder region L2 has a plurality of fifth sipes 25, while the remaining shoulder region L3 has a plurality of sixth sipes 26.

[0218] In each shoulder region L2, L3, the fifth sipes 25 and the sixth sipes 26 extend axially over at least 70% of the width of the shoulder region L2, L3 in which they lie.

[0219] Preferably, the fifth sipes 25 and the sixth sipes 26 extend axially over at least 90% of the width of the respective shoulder region L2, L3 in which they lie.

[0220] In order to improve the traction and braking features during straight-line travel, in particular on snow-covered roads, the extension of the fifth sipes 25 and of the sixth sipes 26 substantially follows the extension of the shoulder transverse grooves 13, 14. In detail, in each shoulder region L2, L3, the fifth sipes 25 and the sixth sipes 26 extend parallel to each other and in a direction substantially parallel to the shoulder transverse grooves 13, 14.

[0221] With reference to Figure 2 In the illustrated embodiment, the fifth sipes 25 and the sixth sipes 26 have an inclination ω' with respect to the equatorial plane X-X of between 60° and 90°, preferably of between 75° and 90°.

[0222] Preferably, the fifth sipes 25 and the sixth sipes 26 have a maximum width of less than about 1 mm.

[0223] Preferably, the fifth sipes 25 and the sixth sipes 26 do not have a constant depth along their extension, but rather, as illustrated in the preferred embodiment, they have a maximum depth at their central portion and at least two respective cross-section reductions at their ends. ​ More preferably, as illustrated, they have a maximum depth at their central portion and at least two respective cross-section reductions at their ends.

[0224] Preferably, the fifth sipes 25 and the sixth sipes 26 have a maximum depth of greater than about 4 mm. The fifth sipes 25 and the sixth sipes 26 have a maximum depth of less than about 10 mm.

[0225] Preferably, the maximum depth of the fifth sipes 25 and of the sixth sipes 26 is less than the maximum depth of the circumferential grooves 2, 3, 4, 5.

[0226] Preferably, the fifth sipes 25 and / or the sixth sipes 26 have a minimum distance between each other in the circumferential direction of greater than or equal to 6 mm.

[0227] In the preferred embodiment, the fifth sipes 25 and the sixth sipes 26 are formed as described in the patent application WO2017 / 212399 of the same applicant, which is incorporated herein by reference.

[0228] The tyres of size 255 / 55R18 of the model Scorpion Verde AS+ currently sold by the Applicant (comparative) were compared with tyres of the same size and having the tread pattern according to an embodiment of the application shown in the attached drawings (application).

[0229] Both tyres were fitted with an inflation pressure of 2.4 bar.

[0230] The Volvo XC 90 car was first equipped with four tyres manufactured according to the application and then with four comparative tyres.

[0231] The running behaviour tests were performed on dry and wet road surfaces and on ice and snow covered surfaces and the rolling resistance and braking distance were measured on dry, wet and snow covered ground with the instruments.

[0232] The running behaviour tests were performed on dry, wet and snow covered road surfaces, on predetermined paths, typically closed traffic circuits. The performance of the tyres was assessed by the test driver through numerical evaluation of the behaviour of the tyres during some characteristic manoeuvres simulated at constant speed and with acceleration and deceleration, such as lane change, overtake, turn between traffic cones, entry and exit of a curve.

[0233] Tests were also performed on internal and external noise, in particular subjective tests, i.e. based on the perception of the test driver.

[0234] The results of the tests are shown in Table I, in which the rating values are expressed in percentage, setting the value of the comparative tyre as 100. As for the running behaviour tests and the subjective noise evaluation, the rating scale represents the subjective assessment made by the test driver in order of testing the comparative group.

[0235] In the case of the mileage tests, a value greater than 100 indicates the percentage improvement in terms of lower tread wear (measured in recess depth) on a mixed route of distances including motorway, highway, secondary road and urban road compared with the comparative tyre.

[0236] In the case of the rolling resistance measurements, a value greater than 100 indicates lower rolling resistance (proportionally, the rolling resistance of the comparative tyre is taken as a reference of 100) compared with the comparative tyre.

[0237] In the case of the braking distance measurements, a value greater than 100 indicates a shorter braking distance on the relevant ground compared with the comparative tyre.

[0238] Table I

[0239]

[0240]

[0241] Accordingly, the tyre of the present application shows a global improvement and, in particular, very significant improvements in terms of mileage, braking, traction and behaviour on snow.

[0242] Various modifications can be made to the embodiments described in detail herein, while remaining within the scope of the application as defined by the appended claims.

Claims

1. A car tire (1) having a tread belt (7) comprising: The central region (L1) extends across the equatorial plane (XX); And two shoulder regions (L2, L3) separated from the central region by two first circumferential grooves (2, 3); The central region (L1) has at least one central rib (8) and at least two rows (9, 10) of lateral blocks, the central rib (8) comprising a plurality of central blocks (30), and the at least two rows (9, 10) of lateral blocks being opposite to each other relative to the central rib (8) and comprising a plurality of lateral blocks (31, 32). The central rib (8) is axially defined by two second circumferential grooves (4, 5), and the plurality of central blocks (30) are defined by corresponding plurality of first curved grooves (15); Each first curved groove (15) extends between the second circumferential groove (4, 5) and the circumferentially successive first curved groove (15) to form one of the central blocks (30); The side blocks (31, 32) of each row (9, 10) are separated from each other by means of a plurality of second curved grooves (16) which are distributed along the entire circumference of the tire and have an extension equal to at least 95% of the width of the corresponding row (9, 10) of the side blocks. - Each of the second curved grooves (16) includes a first, substantially straight section (16') that is inclined relative to a direction parallel to the equatorial plane (XX) to form an angle θ greater than or equal to 45°, a second, substantially straight section (16'') that is inclined in the opposite direction to the first section (16'), and a curved connecting section (16''') that extends between the first section (16') and the second section (16''). The tread band (7) also includes a plurality of sipes (21, 22, 23, 24, 25), the plurality of sipes including a plurality of first sipes (21) located in the central rib (8) between one of the first curved groove (15) and the second circumferential groove (4, 5).

2. The tire (1) according to claim 1, characterized in that, The second curved groove (16) has an extension equal to 100% of the width of the corresponding row (9, 10) of the lateral blocks (31, 32).

3. The tire (1) according to claim 1, characterized in that, The rows (9, 10) of the lateral blocks have no gaps and are annular portions with a rubber ratio of zero.

4. The tire (1) according to any one of claims 1 to 3, characterized in that, The central rib (8) has no gaps and is an annular portion with a rubber ratio of zero.

5. The tire (1) according to any one of claims 1 to 3, characterized in that, The second segment (16'') has an extension that is less than or equal to 1 / 3 of the extension of the first segment (16'').

6. The tire (1) according to any one of claims 1 to 3, characterized in that, The angle θ is between 50° and 80°.

7. The tire (1) according to any one of claims 1 to 3, characterized in that, The central rib (8) includes an annular portion (6) with a void-to-rubber ratio greater than 0.

05.

8. The tire (1) according to claim 7, characterized in that, The annular portion (6) is defined in the axial direction by one of the second circumferential grooves (4) and the plurality of first curved grooves (15).

9. The tire (1) according to claim 7, characterized in that, The annular portion (6) includes the plurality of first groove patterns (21).

10. The tire (1) according to claim 9, characterized in that, The gaps and rubber ratio of the annular portion (6) are generated solely by the first groove pattern (21).

11. The tire (1) according to claim 9 or 10, characterized in that, The first groove pattern (21) extends in a substantially straight line between the second circumferential groove (4) and the first curved groove (15).

12. The tire (1) according to claim 9 or 10, characterized in that, The first groove pattern (21) is inclined relative to the equatorial plane (XX) so as to form an angle β' greater than 45°.

13. The tire (1) according to claim 12, characterized in that, The angle β' includes angles between 50° and 80°.

14. The tire (1) according to any one of claims 1 to 3, characterized in that, The first curved groove (15) includes a generally straight first segment (15') inclined relative to a direction parallel to the equatorial plane (XX) so as to form an angle β greater than 45°.

15. The tire (1) according to claim 14, characterized in that, The angle β includes angles between 50° and 80°.

16. The tire (1) according to any one of claims 1 to 3, characterized in that, The first curved groove (15) includes a curved second section (15'') arranged in the basic circumferential direction.

17. The tire (1) according to any one of claims 1 to 3, characterized in that, The central block (30) includes multiple second groove patterns (22).

18. The tire (1) according to claim 17, characterized in that, At least some of the second groove pattern (22) extends between one of the second circumferential grooves (5) and the first curved circumferential groove (15).

19. The tire (1) according to claim 17, characterized in that, The second groove pattern (22) is inclined relative to the equatorial plane (XX) to form an angle β'' greater than 45°; the second groove pattern (22) is inclined in the opposite direction to the first groove pattern (21).

20. The tire (1) according to claim 19, characterized in that, The angle β'' includes angles between 50° and 80°.

21. The tire (1) according to claim 17, characterized in that, In each central block (30), at least some of the second groove patterns (22) include a central section (22') with a zigzag pattern.

22. The tire (1) according to any one of claims 1 to 3, characterized in that, One row (9) of the side block (31) includes a plurality of third groove patterns (23), and another row (10) of the side block (32) includes a plurality of fourth groove patterns (24).

23. The tire (1) according to claim 22, characterized in that, The third groove pattern (23) extends substantially parallel to each other and extends in a direction substantially parallel to the first segment (16') of the second curved groove (16) of the corresponding row (9) of the lateral block (31).

24. The tire (1) according to claim 22, characterized in that, The fourth groove pattern (24) extends substantially parallel to each other and in a direction that is inclined in the opposite direction to the direction of the straight first segment (16) of the second curved groove (16) of the corresponding row (10) of the lateral block (32).

25. The tire (1) according to claim 22, characterized in that, At least some of the fourth groove patterns (24) include a central section (24') with a zigzag pattern.

26. The tire (1) according to claim 22, characterized in that, The third groove pattern (23) is inclined in the opposite direction to the fourth groove pattern (24).

27. The tire (1) according to any one of claims 1 to 3, characterized in that, The two shoulder regions (L2, L3) include rows (11, 12) of shoulder blocks (33, 34) separated from each other by shoulder transverse grooves (13, 14), the shoulder transverse grooves (13, 14) having a width greater than or equal to 3 mm.

28. The tire (1) according to claim 27, characterized in that, One row (11) of the shoulder block (33) includes a plurality of fifth groove patterns (25), and another row (12) of the shoulder block (34) includes a plurality of sixth groove patterns (26).

29. The tire (1) according to claim 28, characterized in that, The fifth groove pattern (25) or the sixth groove pattern (26) extends substantially parallel to each other and substantially parallel to the extension direction of the shoulder transverse grooves (13, 14).

30. The tire (1) according to any one of claims 1 to 3, characterized in that, Each group of multiple grooving patterns (21, 22, 23, 24, 25, 26) has circumferential continuous grooving pattern pairs that do not have mutual intersections and are arranged at a minimum distance of 6 mm or more in the circumferential direction.

31. The tire (1) according to any one of claims 1 to 3, characterized in that, The first circumferential groove (2, 3) and the second circumferential groove (4, 5) have a width of less than 15 mm.

32. The tire (1) according to any one of claims 1 to 3, characterized in that, The first curved groove or the second curved groove (15) has a width greater than 2 mm.

33. The tire (1) according to any one of claims 1 to 3, characterized in that, The first curved groove or the second curved groove (16) has a width of less than or equal to 5 mm.

34. The tire (1) according to claim 33, characterized in that, The first curved groove or the second curved groove (16) has a width of less than or equal to 4 mm.

35. The tire (1) according to any one of claims 1 to 3, characterized in that, The first section (15') of the first curved groove (15) is substantially aligned with the first section (16') of the second curved groove (16).

36. The tire (1) according to any one of claims 1 to 3, characterized in that, In row (9) of the lateral block (31), the curved connecting segment (16''') connects the first segment (16') and the second segment (16'') to define a concavity oriented in a first circumferential direction, while in another row (10) of the lateral block (32), the curved connecting segment (16''') connects the first segment (16') and the second segment (16'') to define a concavity oriented in a second circumferential direction opposite to the first circumferential direction.

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