tire

Abstract

To improve wear resistance performance and grip performance while securing wet performance.SOLUTION: A tire 10 having, on a tread surface 1, two circumferential grooves 2 extending in a tire circumferential direction CD and three ribs 3 partitioned by the two circumferential grooves 2, the two peripheral grooves 2 are disposed on the vehicle-installed side IN with respect to the tire equatorial plane CL, and the two peripheral grooves 2 are referred to as a first peripheral groove 21 and a second peripheral groove 22 in order from the vehicle-installed side IN, when the three ribs 3 are referred to as a first rib 31, a second rib 32, and a third rib 33 in order from the vehicle-mounted inner side IN, the three ribs 3 have the relationships of the groove-width WG2 of the second peripheral groove 22 <the groove-width WG1 of the first peripheral groove 21, and the rib-width WR1 of the first rib 31 <the rib-width WR2 of the second rib 32 <the rib-width WR3 of the third rib 33.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a tire. [Background technology]

[0002] Tires have been proposed that have advantages such as improved wet road performance on ordinary roads and good wear resistance on circuits. For example, Patent Document 1 proposes a tire that has two circumferential grooves and three rib rows defined by the grooves in the tread, with the widths of the circumferential grooves and the rib rows specified. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-225511 Summary of the Invention [Problem to be solved by the invention]

[0004] However, it has been found that even with a tire such as that described in Patent Document 1, there is still room for improvement in terms of ensuring and improving wet performance, wear resistance, and grip performance in a balanced manner, particularly during high-speed driving such as in a race.

[0005] Therefore, an object of the present invention is to provide a tire that can improve wear resistance and grip performance while maintaining wet performance. [Means for solving the problem]

[0006] The means for achieving the above objectives are as follows:

[0007] (1) The tire of the present invention is A tire having, on a tread surface, two circumferential grooves extending in the tire circumferential direction and three ribs defined by the two circumferential grooves, The two circumferential grooves are disposed on the inner side of the tire equatorial plane when mounted on the vehicle, When the two circumferential grooves are referred to as a first circumferential groove and a second circumferential groove in order from the vehicle mounting inner side, and the three ribs are referred to as a first rib, a second rib, and a third rib in order from the vehicle mounting inner side, The groove width of the second circumferential groove<the groove width of the first circumferential groove, and the rib width of the first rib<the rib width of the second rib<the rib width of the third rib have the following relationship. According to the tire of the present invention, it is possible to improve the wear resistance and grip performance while ensuring the wet performance.

[0008] (2) In the tire described in (1) above, Preferably, the third rib is provided with a plurality of second lug grooves spaced apart in the tire circumferential direction, the second lug grooves extending in the tire width direction and having both ends terminating within the third rib. In this case, the grip performance can be further improved.

[0009] (3) In the tire described in (2) above, The first rib is provided with a plurality of first notches that open into the first circumferential groove and are spaced apart in the tire circumferential direction, The second rib is provided with a plurality of second notches that open into the first circumferential groove and are spaced apart in the tire circumferential direction, The third rib is preferably provided with a plurality of third notches that open into the second circumferential groove and are spaced apart in the tire circumferential direction. In this case, the grip performance can be further improved.

[0010] (4) In the tire of (3) above, The first rib is preferably provided with a plurality of first lug grooves spaced apart in the tire circumferential direction, the first lug grooves extending in the tire width direction and having one end opening at a tread edge on the vehicle mounting inner side. In this case, the grip performance can be further improved.

[0011] (5) In the tire described in (3) or (4) above, It is preferable that the second lug groove and the third notch are arranged so as not to overlap each other when viewed in the tire width direction. In this case, the grip performance can be further improved.

[0012] (6) In the tire of (4) above, The first lug groove is preferably arranged so as not to overlap the first notch and the second notch when viewed in the tire width direction. In this case, the grip performance can be further improved.

[0013] (7) In any one of the tires (4) to (6) above, Of the first lug grooves, the first notch, the second notch, the third notch, and the second lug grooves, it is preferable that the first lug grooves, the first notch, the second notch, the third notch, and the second lug grooves that are adjacent to each other in the tire width direction are arranged so as not to overlap each other when viewed in the tire width direction. In this case, the grip performance can be further improved.

[0014] (8) In any one of the tires (4) to (7) above, The first lug groove and the first notch are preferably arranged to overlap each other when viewed in the tire circumferential direction. In this case, the grip performance can be further improved.

[0015] (9) In any one of the tires (1) to (8), The groove width of the first circumferential groove and the groove width of the second circumferential groove are both 6 to 11% of the tread width, It is preferable that the rib width of the first rib, the rib width of the second rib, and the rib width of the third rib are 10% or less, 20% or less, and 60% or less of the tread width, respectively. In this case, it is possible to improve the wear resistance and grip performance in a well-balanced manner while ensuring sufficient wet performance. [Effects of the Invention]

[0016] According to the present invention, it is possible to provide a tire that can improve wear resistance and grip performance while maintaining wet performance. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a development view of a tread surface of a tire according to one embodiment of the present invention, developed on a plane. [Figure 2] FIG. 1 is a diagram illustrating an example of the arrangement of communication devices. DETAILED DESCRIPTION OF THE INVENTION

[0018] The tire according to the present invention can be suitably used for any type of tire, for example, a tire for a passenger car, and in particular, a racing / sports tire that can be used in races as well as on general roads.

[0019] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a tire according to the present invention will be described by way of example with reference to the drawings. In each drawing, the same members and parts are designated by the same reference numerals. In this specification, the "tire circumferential direction" refers to the direction in which the tire rotates around the tire's rotational axis, and the "tire width direction" refers to the direction parallel to the tire's rotational axis. In some drawings, the tire circumferential direction is indicated by the symbol "CD," the tire width direction is indicated by the symbol "WD," the vehicle mounting inner side (the side that is the inside of the vehicle in the tire width direction when the tire is mounted on a vehicle) is indicated by the symbol "IN," and the vehicle mounting outer side (the side that is the outside of the vehicle in the tire width direction when the tire is mounted on a vehicle) is indicated by the symbol "OUT." In this specification, the side closer to the tire equatorial plane CL along the tire width direction is referred to as the "inner side in the tire width direction," and the side farther from the tire equatorial plane CL along the tire width direction is referred to as the "outer side in the tire width direction." Furthermore, in this specification, "extending in the tire circumferential direction" means extending with at least a tire circumferential component, "extending along the tire circumferential direction" means extending parallel to the tire circumferential direction (in other words, at an angle of 0° with respect to the tire circumferential direction), "extending in the tire width direction" means extending with at least a tire width direction component, and "extending along the tire width direction" means extending parallel to the tire width direction (in other words, at an angle of 0° with respect to the tire width direction).

[0020] Although detailed description will be omitted, the tire of the embodiment described below can have a general tire structure, for example, in which sidewall portions extending radially outward from a pair of bead portions and a tread portion spanning between both sidewall portions are connected, a carcass having, for example, a carcass ply of a radial structure made of, for example, organic fiber cords or steel cords extending from one bead portion through the tread portion to the other bead portion, and a belt having a belt layer made of, for example, steel cords arranged between the carcass and the tread rubber of the tread portion.

[0021] Unless otherwise specified, the positional relationship and dimensions of each element are measured under a standard condition in which the tire is mounted on an applicable rim, inflated to a specified internal pressure, and unloaded. In this specification, the term "tread surface" refers to the portion of the tire widthwise region, centered on the tire equatorial plane CL, that has a width in the tire widthwise direction equivalent to 75% of the width in the tire widthwise direction of the portion of the outer peripheral surface that contacts the road surface when the tire is mounted on an applicable rim, inflated to a specified internal pressure, and under maximum load. The tire widthwise width of the tread surface is referred to as the "tread width (TW)," and both end edges of the tread surface in the tire widthwise direction are referred to as the "tread edges (TE)." Here, the tire widthwise width of the outer peripheral surface portion, the tread width, and the dimensions of each element of the tread surface, such as the grooves, are measured in a developed tread view. In this specification, the term "developed tread view" refers to a planar view of the tread surface with the tread surface unfolded on a plane. In this specification, a "circumferential groove" refers to a groove extending in the tire circumferential direction and having a groove width (opening width on the tread surface) of 2 mm or more. A "lug groove" refers to a groove that does not open (connect) to a circumferential groove extending in the tire width direction and has a groove width (opening width on the tread surface) of 2 mm or more over 80% or more of its extension length. A "notch" refers to a groove-like notch that extends in the tire width direction and opens (connects) to a circumferential groove and has a notch width (opening width on the tread surface) of 2 mm or more. Here, the above "groove width" and "notch width" are measured perpendicular to their extension direction (extension direction of the centerline) in a developed view of the tread. In addition, in this specification, a "rib" refers to a land portion defined by a circumferential groove on the tread surface, and a "rib width" refers to the width measured perpendicular to its extension direction (extension direction of the centerline) in a developed view of the tread. In addition, except for the groove width of the lug groove, when the "groove width," "notch width," or "rib width" varies within the tread surface, it refers to the maximum value.

[0022] In this specification, the term "applicable rim" refers to the standard rim (Measuring Rim in the ETRTO Standards Manual and Design Rim in the TRA Year Book) for the applicable size, which is an industry standard valid in the region where the tire is produced and used, and which is described or will be described in the future, such as the JATMA Year Book of the Japan Automobile Tire Manufacturers Association (JATMA) in Japan, the European Tyre and Rim Technical Organization (ETRTO) Standards Manual in Europe, and the Tire and Rim Association, Inc. (TRA) Year Book in the United States. However, for sizes not described in these industry standards, the term refers to a rim with a width corresponding to the tire's bead width. "Applicable rim" includes not only current sizes but also sizes that will be described in the aforementioned industry standards in the future. An example of a "size to be described in the future" is the size described as "FUTURE DEVELOPMENTS" in the 2013 edition of the ETRTO.

[0023] In this specification, "specified internal pressure" refers to the air pressure (maximum air pressure) corresponding to the maximum load capacity of a single wheel for the applicable size and ply rating as set forth in the aforementioned industrial standards, such as the JATMA Yearbook, or, in the case of a size not set forth in the aforementioned industrial standards, refers to the air pressure (maximum air pressure) corresponding to the maximum load capacity specified for each vehicle on which the tire is to be mounted. Furthermore, in this specification, "maximum load" refers to the load corresponding to the maximum load capacity of the tire for the applicable size as set forth in the aforementioned industrial standards, or, in the case of a size not set forth in the aforementioned industrial standards, the load corresponding to the maximum load capacity specified for each vehicle on which the tire is to be mounted.

[0024] Fig. 1 is a drawing for explaining a tire according to one embodiment of the present invention. Fig. 1 is a diagram showing the tread pattern of a tire according to one embodiment of the present invention, and is a development view in which the tread surface of the tire is developed on a plane.

[0025] The tire 10 of this embodiment is configured as a tire for passenger cars. More specifically, the tire 10 is configured as a racing / sports tire that can be used in races and also on public roads, and can even be sold commercially to general users. However, the tire 10 of this embodiment may be a tire of a type other than the above. More specifically, the tire 10 of this embodiment is a pneumatic radial tire for passenger cars. The tire 10 of this embodiment is configured as a tire whose mounting direction on a vehicle is specified by markings on the tire, an instruction manual, or the like.

[0026] As shown in FIG. 1, the tire 10 of this embodiment has, on a tread surface 1, two circumferential grooves 2 (21, 22) extending in the tire circumferential direction and three ribs 3 (31, 32, 33) defined by the two circumferential grooves.

[0027] Each circumferential groove 2 extends in the tire circumferential direction. More specifically, in this embodiment, each circumferential groove 2 extends continuously over the entire tire circumferential direction. Even more specifically, each circumferential groove 2 extends linearly along the tire circumferential direction, as shown in FIG. 1 . Furthermore, both opening edge portions of each circumferential groove 2 toward the tread surface 1 also extend linearly along the tire circumferential direction, as shown in FIG. 1 . However, each circumferential groove 2 or both opening edge portions of each circumferential groove 2 toward the tread surface 1 may extend in the tire circumferential direction in a zigzag shape, a smooth wave shape, or the like.

[0028] In this embodiment, as described above, the tire 10 has two circumferential grooves 2 extending in the tire circumferential direction on the tread surface 1. In this embodiment, the tire 10 has only two circumferential grooves 2. In this embodiment, as shown in FIG. 1 , the two circumferential grooves 2 are arranged on the vehicle mounting inner side IN of the tire equatorial plane CL. In other words, when the two circumferential grooves 2 are referred to as the first circumferential groove 21 and the second circumferential groove 22 in order from the vehicle mounting inner side IN, both the first circumferential groove 21 and the second circumferential groove 22 are arranged on the vehicle mounting inner side IN of the tire equatorial plane CL in the tire width direction WD. Here, when one circumferential groove 2 is "arranged on the vehicle mounting inner side IN of the tire equatorial plane CL," this means that the entire one circumferential groove 2 is arranged on the vehicle mounting inner side IN of the tire equatorial plane CL.

[0029] Particularly during high-speed cornering, the outermost vehicle-mounted rib 3 (the third rib 33, described later) is susceptible to accelerated wear due to increased ground contact pressure. Here, as described above, by arranging the two circumferential grooves 2 on the inner side IN of the tire equatorial plane CL, a large area of ​​the tread surface 1 of the outermost vehicle-mounted rib 3 (the third rib 33) can be ensured, and thus, an increase in ground contact pressure at the outermost vehicle-mounted rib 3 (the third rib 33) can be kept low. Therefore, in this case, the wear resistance of the outermost vehicle-mounted rib 3 (the third rib 33) and, in turn, the tire 10 is improved. Furthermore, as a result of being able to ensure a large area of ​​the outermost vehicle-mounted rib 3 (the third rib 33), the rigidity of the rib 3 (the third rib 33) against input in the tire width direction WD is increased, and the grip performance of the rib 3 (the third rib 33) and, in turn, the tire 10, particularly during cornering, is also improved. In this embodiment, the tire 10 has two circumferential grooves and three ribs 3, so that the basic wet performance (drainage performance in wet conditions) of the tire 10 is ensured.

[0030] In this embodiment, as described above, the tire 10 has three ribs 3 defined by two circumferential grooves 2 on the tread surface 1. In other words, when the three ribs 3 are referred to as the first rib 31, the second rib 32, and the third rib 33 in order from the vehicle mounting inner side IN, the tire 10 has, as shown in Fig. 1 , the first rib 31 defined by the tread edge TE on the vehicle mounting inner side IN and the first circumferential groove 21, the second rib 22 defined by the first circumferential groove 21 and the second circumferential groove 22, and the third rib 33 defined by the second circumferential groove 22 and the tread edge TE on the vehicle mounting outer side OUT. In this embodiment, the first rib 31, the second rib 32, and the third rib 33 are all land portions that extend continuously in the tire circumferential direction CD within the tread surface 1; that is, they are not divided in the tire circumferential direction CD by grooves or the like (in this embodiment, lug grooves 4 and notches 5, which will be described later) that extend in the tire width direction within the tread surface 1. However, the first rib 31 may be divided in the tire circumferential direction CD within the tread surface 1 to the extent that the first rib 31 can be regarded as a land portion that substantially extends continuously in the tire circumferential direction CD by a first notch 51, which will be described later, extending to the tread edge TE on the vehicle mounting inner side IN or slightly beyond the tread edge TE into the sidewall portion 6. However, from the viewpoint of ensuring sufficient grip performance in non-wet conditions, it is preferable that the first rib 31 be a land portion that extends continuously in the tire circumferential direction CD within the tread surface 1.

[0031] In this embodiment, the relationship in size between the groove width of each circumferential groove and the rib width of each rib is as follows, as shown in FIG. In this embodiment, the groove width of each circumferential groove and the rib width of each rib have the following relationship: groove width WG2 of second circumferential groove 22<groove width WG1 of first circumferential groove 21, and rib width WR1 of first rib 31<rib width WR2 of second rib 32<rib width WR3 of third rib 33. That is, the circumferential grooves 2 are configured so that the groove width becomes smaller as the circumferential groove 2 is closer to the vehicle mounting outer side (OUT), and the rib width becomes larger as the rib 3 is closer to the vehicle mounting outer side (OUT).

[0032] This improves the wear resistance and grip performance while maintaining wet performance. In particular, the rib width and area of ​​the outermost third rib 33 mounted on the vehicle are increased, resulting in improved grip performance and wear resistance, as described above. Furthermore, particularly during high-speed driving, a reinforcing member (such as a belt in a radial structure) arranged radially inward of the tread rubber near the position of the tire equatorial plane CL may approach the tread surface near the tire equatorial plane CL, which may increase the ground contact pressure at the tire width direction end of the rib adjacent to the circumferential groove. However, according to this embodiment, the groove width WG2 of the second circumferential groove 22 near the tire equatorial plane CL is made smaller than the groove width WG1 of the first circumferential groove 21. This reduces the degree to which the reinforcing member approaches the groove bottom of the second circumferential groove 22 compared to when the groove width WG2 of the second circumferential groove 22 is equal to or greater than the groove width WG1 of the first circumferential groove 21. As a result, an increase in ground contact pressure and therefore an increase in wear are suppressed, particularly near the tire width direction WD outer end (i.e., the vehicle-mounted outer OUT end) 32e (see Figure 1) of the second rib 32 adjacent to the inner side of the second circumferential groove 22 in the tire width direction WD, thereby improving the wear resistance of the second rib 32 and, in particular, the tire 10. Furthermore, according to this embodiment, the rib width WR2 of the second rib 32 is larger than the rib width WR1 of the first rib 31, so the contact area of ​​the second rib 32 can be increased compared to when the rib width WR2 of the second rib 32 is equal to or smaller than the rib width WR1 of the first rib 31, thereby improving the wear resistance and grip performance of the second rib 32 and ultimately the tire 10.

[0033] In this embodiment, as shown in FIG. 1, the first rib 31 and the third rib 33 are each provided with a plurality of lug grooves 4 (41, 42) extending in the tire width direction at intervals in the tire circumferential direction CD.

[0034] In this embodiment, as shown in FIG. 1, the first rib 31 is provided with a plurality of first lug grooves 41 spaced apart in the tire circumferential direction CD, each first lug groove 41 extending in the tire width direction WD and having one end opening to the tread edge TE on the vehicle mounting inner side IN. The first lug grooves 41 extend in the tire width direction WD. In the present embodiment, as shown in FIG. 1 , the first lug grooves 41 start within the first rib 31, extend toward the vehicle mounting inner side IN, open at the tread edge TE on the vehicle mounting inner side IN, and further extend within the sidewall portion 6 to terminate at the shoulder portion. The first lug grooves 41 do not open into the first circumferential groove 21. Although not particularly limited, in the example of FIG. 1 , the first lug grooves 41 extend within the first rib 31 over a length in the tire width direction WD that is more than 50% of the rib width WR1 of the first rib 31. In the example of FIG. 1 , the first lug grooves 41 (more specifically, the center line of the extending direction of the first lug grooves 41) extend at a small angle of, for example, 20° or less with respect to the tire width direction WD. However, the first lug grooves 41 may extend parallel to the tire width direction WD or at an angle of more than 20° and, for example, 45° or less with respect to the tire width direction WD. The outer contour shape of the first lug grooves 41 on the tread surface 1 is substantially triangular in the example of Fig. 1, but the outer contour shape is not particularly limited. In the example of Fig. 1, the distances in the tire circumferential direction CD between adjacent first lug grooves 41 are constant all around the tire 10, but may be different from each other at least in part.

[0035] By providing the first lug grooves 41 as described above in the first rib 31, an effective drainage effect from the road surface is obtained, thereby further improving the grip performance of the first rib 31 and therefore the tire 10 (especially the grip performance when driving straight on wet roads).

[0036] In this embodiment, as shown in FIG. 1, the third rib 33 is provided with a plurality of second lug grooves 42 spaced apart in the tire circumferential direction CD, the second lug grooves 42 extending in the tire width direction WD and terminating at both ends within the third rib 33. The second lug grooves 42 extend in the tire width direction WD. As shown in FIG. 1 , both ends of the second lug grooves 42 terminate within the third rib 33. That is, the second lug grooves 42 do not open to the tread edge TE on the vehicle outer side OUT, nor do they open to the second circumferential groove 22 adjacent to the third rib 33 on the inner side in the tire width direction WD. Although not particularly limited, in the example of FIG. 1 , the second lug grooves 42 extend within the third rib 33 over a length in the tire width direction WD that is more than 50% of the rib width WR3 of the third rib 33. In the example of FIG. 1 , the second lug grooves 42 (more specifically, the center lines of the second lug grooves 42 in the extension direction) extend at a small angle, for example, within 20°, with respect to the tire width direction WD. However, the second lug grooves 42 may extend parallel to the tire width direction WD or at an angle greater than 20° and within 45° with respect to the tire width direction WD. The outer contour shape of the second lug grooves 42 on the tread surface 1 is a flat, generally trapezoidal shape in the example of Fig. 1, but the outer contour shape is not particularly limited. In the example of Fig. 1, the intervals in the tire circumferential direction CD between adjacent second lug grooves 42 are constant all around the tire 10, but may be different from each other at least in part.

[0037] The provision of the second lug grooves 42 as described above in the third rib 33 provides an effective drainage effect from the road surface, further improving the grip performance (particularly grip performance during straight-ahead driving on wet roads) of the third rib 33 and therefore the tire 10. In particular, since the second lug grooves 42 do not open to the tread edge TE on the outer vehicle mounting side OUT, when the ground contact width of the third rib 33, which is the outermost rib mounted on the vehicle of the outer tire on the outside of a turn, increases particularly during cornering, the ground contact area of ​​the third rib 33 increases in response to the increase in the ground contact width, and the grip performance of the third rib 33 can be further improved, compared to when the second lug grooves 42 open to the tread edge TE on the outer vehicle mounting side OUT.

[0038] In this embodiment, as shown in FIG. 1, the first rib 31, the second rib 32 and the third rib 33 each have a plurality of notches 5 (51, 52, 53) that open into the circumferential groove 2 (21, 22) and are spaced apart in the tire circumferential direction CD.

[0039] In this embodiment, as shown in FIG. 1, the first rib 31 is provided with a plurality of first notches 51 that open into the first circumferential groove 21 at intervals in the tire circumferential direction CD. The first notch 51 extends in the tire width direction WD. As shown in FIG. 1 , the vehicle-mounted outer side OUT end of the first notch 51 opens to the first circumferential groove 21. Although not particularly limited, in the example of FIG. 1 , the first notch 51 extends within the first rib 31 over a tire width direction length that is more than 50% of the rib width WR1 of the first rib 31. In the example of FIG. 1 , the vehicle-mounted inner side IN end of the first notch 51 does not reach the tread edge TE and does not open to the tread edge TE. However, as described above, the first notch 51 may extend to the tread edge TE on the vehicle-mounted inner side IN or slightly beyond the tread edge TE into the sidewall portion 6. However, from the viewpoint of ensuring sufficient grip performance in non-wet conditions, it is preferable that the vehicle-mounted inner side IN end of the first notch 51 does not open to the tread edge TE. The outer contour shape of the first notch 51 on the tread surface 1 is substantially rectangular in the example of Fig. 1, but the outer contour shape is not particularly limited. In the example of Fig. 1, the distances in the tire circumferential direction CD between adjacent first notches 51 are constant all around the tire 10, but may be different from each other at least in part.

[0040] By providing the first notch 51 as described above in the first rib 31, an effective drainage effect from the road surface is obtained, thereby further improving the grip performance of the first rib 31 and therefore the tire 10 (especially the grip performance when driving straight on wet roads).

[0041] In this embodiment, as shown in FIG. 1, the second rib 32 is provided with a plurality of second notches 52 that open into the first circumferential groove 21 at intervals in the tire circumferential direction CD. In the example of FIG. 1 , the second notch 52 extends in the tire width direction WD by a small distance in the tire width direction WD. As shown in FIG. 1 , the second notch 52 has its vehicle-mounted inner IN end opening into the first circumferential groove 21. Although not particularly limited, in the example of FIG. 1 , the second notch 52 extends within the second rib 32 by a tire width direction length that is less than 50% of the rib width WR2 of the second rib 32. In the example of FIG. 1 , the vehicle-mounted outer OUT end of the second notch 52 does not reach the second circumferential groove 22 and does not open into the second circumferential groove 22. In the example of FIG. 1 , the outer contour shape of the second notch 52 at the tread surface 1 is substantially triangular, but this outer contour shape is not particularly limited. In the example of FIG. 1 , the distance in the tire circumferential direction CD between second notches 52 adjacent to each other in the tire circumferential direction CD is constant around the entire circumference of the tire 10, but may be different from each other at least in part. In the example of FIG. 1, the second rib 32 does not have a notch that opens into the second circumferential groove 22 in order to ensure sufficient grip performance when the road is not wet.

[0042] By providing the second notch 52 as described above in the second rib 32, an effective drainage effect from the road surface is obtained, thereby further improving the grip performance of the second rib 32 and therefore the tire 10 (especially the grip performance when driving straight on wet roads).

[0043] In this embodiment, as shown in FIG. 1, the third rib 33 is provided with a plurality of third notches 53 that open into the second circumferential groove 22 at intervals in the tire circumferential direction CD. In the example of FIG. 1 , the third notch 53 extends in the tire width direction WD by a small distance in the tire width direction WD. As shown in FIG. 1 , the vehicle-mounted inner IN end of the third notch 53 opens to the second circumferential groove 22. Although not particularly limited, in the example of FIG. 1 , the third notch 53 extends within the third rib 33 by a tire width direction length that is less than 20% of the rib width WR3 of the third rib 33. In the example of FIG. 1 , the vehicle-mounted outer OUT end of the third notch 53 does not reach the tread edge TE and does not open to the tread edge TE. In the example of FIG. 1 , the outer contour shape of the third notch 53 at the tread surface 1 is substantially triangular, but this outer contour shape is not particularly limited. In the example of FIG. 1 , the distance in the tire circumferential direction CD between adjacent third notches 53 in the tire circumferential direction CD is constant around the entire circumference of the tire 10, but may be different from each other at least in part.

[0044] By providing the third notch 53 as described above in the third rib 33, an effective drainage effect from the road surface is obtained, thereby further improving the grip performance of the third rib 33 and, ultimately, the tire 10 (especially, the grip performance when driving straight on wet roads).

[0045] In this embodiment, as shown in FIG. 1, the second lug grooves 42 and the third notches 53 are preferably arranged so as not to overlap each other when viewed in the tire width direction WD. Here, in this specification, "one lug groove 4 or notch 5 and another lug groove 4 or notch 5 overlap (or overlap) each other when viewed in the tire width direction WD" means, in other words, that when countless imaginary tire width direction straight lines (hereinafter also referred to as "tire width direction imaginary lines") parallel to the tire width direction WD on an expanded view of the tread surface 1 such as Figure 1, there exists one tire width direction imaginary line that both the one lug groove 4 or notch 5 and the other lug groove 4 or notch 5 cross. In addition, in this specification, "one lug groove 4 or notch 5 and another lug groove 4 or notch 5 overlap (or overlap) each other when viewed in the tire circumferential direction CD" means, in other words, that when countless imaginary tire circumferential straight lines (hereinafter also referred to as "tire circumferential imaginary lines") parallel to the tire circumferential direction CD are imagined on a developed view of the tread surface 1 such as that in Figure 1, there is one tire circumferential imaginary line that is crossed by both the one lug groove 4 or notch 5 and the other lug groove 4 or notch 5. In other words, in this embodiment, there is no imaginary line in the tire width direction that crosses both the second lug groove 42 and the third notch 53, and in other words, the second lug groove 42 and the third notch 53 are arranged at a distance from each other in the tire circumferential direction CD.

[0046] By arranging the second lug grooves 42 and the third notches 53 as described above, it becomes easier to obtain an effective drainage effect from the road surface at any position of the third rib 33 in the tire circumferential direction CD, and the grip performance of the third rib 33 and therefore the tire 10 (especially the grip performance when driving straight on wet roads) can be further improved.

[0047] In this embodiment, as shown in FIG. 1, the first lug groove 41 is preferably arranged so as not to overlap the first notch 51 and the second notch 52 when viewed in the tire width direction. That is, in this embodiment, there is no imaginary line in the tire width direction that is crossed by both the first lug groove 41 and the first notch 51, and there is no imaginary line in the tire width direction that is crossed by both the first lug groove 41 and the second notch 52. In other words, the first lug groove 41 and the first notch 51 are arranged at an interval from each other in the tire circumferential direction CD, and the first lug groove 41 and the second notch 52 are arranged at an interval from each other in the tire circumferential direction CD.

[0048] By arranging the first lug groove 41 and the first and second notches 51 and 52 as described above, it becomes easier to obtain an effective drainage effect from the road surface at any position in the tire circumferential direction CD of the first rib 31 and the second rib 32 as a whole, and the grip performance of the first rib 31 and the second rib 32 as a whole and therefore the tire 10 (especially the grip performance when driving straight on wet roads) can be further improved.

[0049] In this embodiment, as shown in FIG. 1, among the first lug grooves 41, the first notch 51, the second notch 52, the third notch 53, and the second lug grooves 42, it is preferable that the first lug grooves 41, the first notch 51, the second notch 52, the third notch 53, and the second lug grooves 42 that are adjacent to each other in the tire width direction are arranged so as not to overlap each other when viewed in the tire width direction. That is, in the present embodiment, there is no imaginary line in the tire width direction that the first lug groove 41 and the first notch 51 cross together, there is no imaginary line in the tire width direction that the first notch 51 and the second notch 52 cross together, there is no imaginary line in the tire width direction that the second notch 52 and the third notch 53 cross together, and there is no imaginary line in the tire width direction that the third notch 53 and the second lug groove 42 cross together. In other words, the first lug groove 41 and the first notch 51 are arranged at intervals from each other in the tire circumferential direction CD, the first notch 51 and the second notch 52 are arranged at intervals from each other in the tire circumferential direction CD, the second notch 52 and the third notch 53 are arranged at intervals from each other in the tire circumferential direction CD, and the third notch 53 and the second lug groove 42 are arranged at intervals from each other in the tire circumferential direction CD.

[0050] By arranging the first lug groove 41, the first notch 51, the second notch 52, the third notch 53, and the second lug groove 42 as described above, it becomes easier to obtain an effective drainage effect from the road surface at any position in the tire circumferential direction CD of the first rib 31, the second rib 32, and the third rib 33 as a whole, and the grip performance of the first rib 31, the second rib 32, and the third rib 33 as a whole, and ultimately of the tire 10 (especially grip performance when driving straight on wet roads).

[0051] In this embodiment, as shown in FIG. 1, the first lug grooves 41 and the first notches 51 are preferably arranged so as to overlap each other when viewed in the tire circumferential direction CD. That is, in this embodiment, there is a tire circumferential imaginary line that crosses both the first lug grooves 41 and the first notches 51. In other words, the first lug grooves 41 and the first notches 51 are arranged without any gap between them in the tire width direction WD. Also, although not particularly limited, in the example of Fig. 1, the first lug grooves 41 and the first notches 51 are arranged to overlap each other in a range in the tire width direction WD that is more than 50% of the rib width WR1 of the first rib 31 when viewed in the tire circumferential direction CD.

[0052] Since the first lug grooves 41 and the first notches 51 are arranged so as to overlap each other when viewed in the tire circumferential direction CD, effective drainage from the road surface can be easily achieved at any position of the first rib 31 in the tire circumferential direction CD and the tire width direction WD, thereby further improving the grip performance (especially grip performance in wet conditions) of the first rib 31 and therefore of the tire 10.

[0053] In this embodiment, as shown in Fig. 1, the second lug grooves 42 and the third notches 53 are also arranged to overlap each other as viewed in the tire circumferential direction CD. More specifically, in the example of Fig. 1, the tire width direction WD end of the second lug groove 42 on the vehicle mounting inner side IN and the tire width direction WD end of the third notch 53 on the vehicle mounting outer side OUT are arranged to be on substantially the same tire circumferential imaginary line as viewed in the tire circumferential direction CD. However, the second lug grooves 42 and the third notch 53 may be arranged to overlap each other more as viewed in the tire circumferential direction CD, or may be arranged not to overlap each other as viewed in the tire circumferential direction CD.

[0054] In this embodiment, it is preferable that the dimensions of each circumferential groove 2 and each rib 3 on the tread surface 1 are as follows, thereby enabling a balanced improvement in wear resistance and grip performance while still ensuring sufficient wet performance.

[0055] The groove width WG1 of the first circumferential groove 21 is preferably 6 to 11% of the tread width TW. When the groove width WG1 of the first circumferential groove 21 is 6% or more of the tread width TW, it is easier to ensure sufficient wet performance (drainage performance), and when it is 11% or less, it is easier to ensure a sufficient rib width of the rib 3 adjacent to the first circumferential groove 21, so it is easier to more effectively improve wear resistance and grip performance. For the same reason, the groove width WG2 of the second circumferential groove 22 is also preferably 6 to 11% of the tread width TW.

[0056] The rib width WR1 of the first rib 31 is preferably 10% or less of the tread width TW. By making the rib width WR1 of the first rib 31 10% or less of the tread width TW, it is easier to ensure a sufficient groove width for the circumferential groove 2 adjacent to the first rib 31, and therefore it is easier to ensure more sufficient wet performance (drainage performance). For the same reason, the rib width WR2 of the second rib 32 is preferably 20% or less of the tread width TW. Furthermore, for the same reason, the rib width WR3 of the third rib 33 is preferably 60% or less of the tread width TW.

[0057] In this embodiment, the groove depth or notch depth (groove depth or notch depth measured in a direction perpendicular to the tread surface 1 in the standard state) of each circumferential groove 2 (21, 22), each lug groove 4 (41, 42), and each notch 5 (51, 52, 53) is not particularly limited. For example, the groove depth of the first circumferential groove 21 and the groove depth of the second circumferential groove 22 may be approximately equal.

[0058] Next, the main effects of the embodiment of the present invention described above will be summarized and explained again below as necessary.

[0059] First, in this embodiment, the tire 10 has, on the tread surface 1, two circumferential grooves 2 (21, 22) extending in the tire circumferential direction CD and three ribs 3 (31, 32, 33) defined by the two circumferential grooves 2 (21, 22). Therefore, the tire 10 can ensure basic wet performance and grip performance. In this embodiment, the two circumferential grooves 2 (21, 22) are disposed on the inner side IN of the tire mounted on the vehicle relative to the tire equatorial plane CL. This ensures a large area for the outermost third rib 33 mounted on the vehicle, thereby improving the wear resistance of the third rib 33 and, in particular, the grip performance during cornering. Furthermore, in this embodiment, the groove widths of the circumferential grooves and the rib widths of the ribs satisfy the following relationships: groove width WG2 of second circumferential groove 22<groove width WG1 of first circumferential groove 21, and rib width WR1 of first rib 31<rib width WR2 of second rib 32<rib width WR3 of third rib 33. This ensures a large rib width and therefore a large area for the third rib 33, which is the outermost rib mounted on the vehicle, thereby improving the wear resistance of the third rib 33 and grip performance, particularly during cornering. Also, because the groove width WG2 of the second circumferential groove 22 close to the tire equatorial plane CL is smaller than the groove width WG1 of the first circumferential groove 21, an increase in ground contact pressure and therefore wear near the outer end 32e of the second rib 32 (i.e., the outer end mounted on the vehicle) adjacent to the inner side of the second circumferential groove 22 in the tire width direction WD is suppressed, thereby improving the wear resistance of the second rib 32. Furthermore, since the rib width WR2 of the second rib 32 is larger than the rib width WR1 of the first rib 31, the contact area of ​​the second rib 32 can be increased, thereby improving the wear resistance and grip performance of the second rib 32. As described above, according to this embodiment, it is possible to improve the wear resistance and grip performance while ensuring the wet performance of the tire 10. Furthermore, although the wear resistance and grip performance of rubber are generally in a trade-off relationship, according to this embodiment, the wear resistance and grip performance can be improved by the specific tread pattern described above, and therefore, by using rubber with higher performance in one of the two areas (for example, grip performance) (i.e., lower performance in the other area (for example, wear resistance)) in the tire 10 of this embodiment, it is possible to obtain an advantage in that it is possible to further improve one of the two areas while keeping the other area of ​​performance unchanged.

[0060] In this embodiment, the third rib 33 is provided with a plurality of second lug grooves 42 that extend in the tire width direction WD and have both ends terminating within the third rib 33 at intervals in the tire circumferential direction CD. The third rib 33 is provided with a plurality of second lug grooves 42 extending in the tire width direction WD and spaced apart in the tire circumferential direction CD, which provides effective gripping and draining effects on the road surface and further improves the grip performance (particularly grip performance during straight driving on wet roads) of the third rib 33. In addition, both ends of the second lug grooves 42 terminate within the third rib 33, and therefore the second lug grooves 42 do not open to the tread edge TE on the vehicle outer side OUT, which increases the ground contact area of ​​the third rib 33 and further improves the grip performance of the third rib 33. As described above, according to this embodiment, the grip performance of the tire 10 can be further improved.

[0061] In this embodiment, a plurality of notches 5 (51, 52, 53) opening into specific circumferential grooves 2 (21, 22) are provided at intervals in the tire circumferential direction CD in the first rib 31, the second rib 32, and the third rib 33. In this embodiment, a plurality of first lug grooves 41 extending in the tire width direction WD and having one end opening into a tread edge TE on the vehicle mounting inner side IN are provided at intervals in the tire circumferential direction CD in the first rib 31. These provide an effective gripping effect on the road surface and a water-shedding effect, and the grip performance of the tire 10 (particularly the grip performance when traveling straight on wet roads) can be further improved.

[0062] In the present embodiment, the second lug grooves 42 and the third notches 53 are arranged so as not to overlap with each other when viewed in the tire width direction WD. Also, in the present embodiment, the first lug grooves 41 are arranged so as not to overlap with the first notch 51 and the second notch 52 when viewed in the tire width direction. Furthermore, in the present embodiment, of the first lug grooves 41, the first notch 51, the second notch 52, the third notch 53, and the second lug grooves 42, the first lug grooves 41, the first notch 51, the second notch 52, the third notch 53, and the second lug grooves 42 that are adjacent to each other in the tire width direction are arranged so as not to overlap with each other when viewed in the tire width direction. As a result, effective drainage from the road surface can be easily achieved at any position in the tire circumferential direction CD of each of the first rib 31 to the third rib 33 and the tire as a whole, further improving the grip performance of the tire 10 (especially the grip performance when driving straight on wet roads).

[0063] In this embodiment, the first lug grooves 41 and the first notches 51 are arranged to overlap each other when viewed in the tire circumferential direction CD. This makes it easier to obtain effective water drainage from the road surface at any position of the first rib 31 in the tire circumferential direction CD and tire width direction WD, further improving the grip performance of the tire 10 (especially the grip performance when driving straight on wet roads).

[0064] Other effects of this embodiment are as described above.

[0065] The foregoing describes exemplary embodiments of the present invention, and various modifications can be made without departing from the scope of the claims. For example, in the tire 10 in the above-described embodiment, the ribs 3 (first to third ribs 31 to 33) are provided with lug grooves 4 (first to second lug grooves 41 to 42) and / or notches 5 (first to third notches 51 to 53), but at least one of the lug grooves 4 or notches 3 may not be provided. Furthermore, for example, in the tire 10 in the above-described embodiment, the lug grooves 4 (first to second lug grooves 41 to 42) and / or the notches 5 (first to third notches 51 to 53) have a non-overlapping relationship or an overlapping relationship as described above when viewed in the tire width direction WD or the tire circumferential direction CD, but at least one of them may not have the non-overlapping relationship or the overlapping relationship described above. Furthermore, for example, in the tire 10 in the above-described embodiment, the second rib 32 does not have a notch that opens into the second circumferential groove 22, but the second rib 32 may have a notch that opens into the second circumferential groove 22.

[0066] The following describes a case where a communication device is provided in a tire. The tire may be the tire 10 of the above-described embodiment. FIG. 2 is a diagram illustrating an example of the arrangement of the communication device. As shown in FIG. 2, the tire may be equipped with an RF tag as the communication device 91. The RF tag includes an IC chip and an antenna. The RF tag may be disposed, for example, by being sandwiched between multiple components of the same or different types that constitute the tire. This makes it easy to attach the RF tag during tire production, thereby improving the productivity of tires equipped with RF tags. In this example, the RF tag may be disposed, for example, by being sandwiched between a bead filler and another component adjacent to the bead filler. The RF tag may also be embedded in any of the components that constitute the tire. This reduces the load on the RF tag compared to when the RF tag is disposed by being sandwiched between multiple components that constitute the tire. This improves the durability of the RF tag. In this example, the RF tag may be embedded in a rubber component such as a tread rubber or side rubber. It is preferable that the RF tag is not placed at a position that is a boundary between members with different rigidities in the periphery length direction, which is the direction along the outer surface of the tire in a cross-sectional view in the tire width direction. In this way, the RF tag is not placed at a position where strain is likely to concentrate due to a difference in rigidity. Therefore, the load applied to the RF tag can be reduced. This can improve the durability of the RF tag. In this example, it is preferable that the RF tag is not placed at a position that is, for example, a boundary between an end of the carcass and a member adjacent to the end of the carcass (e.g., a side rubber, etc.) in a cross-sectional view in the tire width direction. The number of RF tags is not particularly limited. A tire may be equipped with only one RF tag, or may be equipped with two or more RF tags. Here, an RF tag is described as an example of a communication device, but a communication device other than an RF tag may also be used.

[0067] The RF tag may be disposed, for example, in the tread portion of the tire. In this manner, the RF tag will not be damaged by a side cut of the tire. The RF tag may be disposed, for example, in the tread center portion in the tire width direction. The tread center portion is a position in the tread portion where flexure is less likely to concentrate. In this manner, the load applied to the RF tag can be reduced. This improves the durability of the RF tag. Also, it is possible to prevent differences in communication with the RF tag from both outer sides of the tire in the tire width direction. In this example, the RF tag may be disposed, for example, within a range of 1 / 2 the tread width centered on the tire equatorial plane CL in the tire width direction. The RF tag may be disposed, for example, at a tread edge in the tire width direction. If the position of a reader that communicates with the RF tag is predetermined, the RF tag may be disposed, for example, at a tread edge on one side closer to the reader. In this example, the RF tag may be disposed, for example, within a range of 1 / 4 the tread width in the tire width direction, with the tread edge as the outer end.

[0068] The RF tag may be positioned, for example, closer to the tire cavity than a carcass including one or more carcass plies spanning between bead portions. This configuration makes the RF tag less susceptible to damage from external impacts to the tire, side cuts, nail penetration, and other damage. As one example, the RF tag may be positioned in close contact with the surface of the carcass facing the tire cavity. As another example, if there is another component closer to the tire cavity than the carcass, the RF tag may be positioned between the carcass and another component located closer to the tire cavity than the carcass. An example of another component located closer to the tire cavity than the carcass is an inner liner that forms the tire inner surface. As another example, the RF tag may be attached to the inner surface of the tire facing the tire cavity. Configuring the RF tag to be attached to the inner surface of the tire makes it easier to attach the RF tag to the tire and to inspect and replace the RF tag. In other words, the ease of attaching and maintaining the RF tag can be improved. Furthermore, by attaching the RF tag to the inner surface of the tire, it is possible to prevent the RF tag from becoming the core of tire failure, compared to a configuration in which the RF tag is embedded in the tire. Furthermore, when the carcass has multiple carcass plies and there is a position where multiple carcass plies are overlapped, the RF tag may be disposed between the overlapped carcass plies.

[0069] The RF tag may be arranged, for example, in the tread portion of the tire, radially outward of a belt including one or more belt plies. As one example, the RF tag may be arranged radially outward of the belt in the tire radial direction and in close contact with the belt. As another example, if a reinforcing belt layer is provided, the RF tag may be arranged radially outward of the reinforcing belt layer in close contact with the reinforcing belt layer. As another example, the RF tag may be embedded in the tread rubber radially outward of the belt. By arranging the RF tag radially outward of the belt in the tread portion of the tire, communication with the RF tag from outside the tire in the tire radial direction is less likely to be obstructed by the belt. Therefore, communication with the RF tag from outside the tire in the tire radial direction can be improved. As another example, the RF tag may be arranged radially inward of the belt in the tread portion of the tire. In this way, the radially outward side of the RF tag is covered by the belt, making the RF tag less susceptible to damage from impacts from the tread surface or nail penetration. As one example, the RF tag may be placed in the tread portion of the tire, between the belt and the carcass located radially inward of the belt. Also, if the belt has multiple belt plies, the RF tag may be placed in the tread portion of the tire, between any two belt plies. In this way, the outer side of the RF tag in the tire radial direction is covered by one or more belt plies, making the RF tag less susceptible to damage from impacts from the tread surface or nail penetration.

[0070] The RF tag may be disposed, for example, in a sidewall portion or a bead portion of the tire. The RF tag may be disposed, for example, in one sidewall portion or one bead portion that is closer to a reader capable of communicating with the RF tag. This arrangement improves communication between the RF tag and the reader. As an example, the RF tag may be disposed between the carcass and the side rubber or between the tread rubber and the side rubber. The RF tag may be disposed, for example, between the tire's maximum width position and the tread surface position in the tire radial direction. This arrangement improves communication with the RF tag from outside the tire in the tire radial direction, compared to a configuration in which the RF tag is disposed radially inward of the tire's maximum width position. The RF tag may be disposed, for example, radially inward of the tire's maximum width position. This arrangement allows the RF tag to be disposed near the bead portion, which has high rigidity. This reduces the load applied to the RF tag, thereby improving the durability of the RF tag. As an example, the RF tag may be disposed adjacent to the bead core in the tire radial direction or the tire width direction. Distortion is less likely to concentrate near the bead core. This reduces the load on the RF tag, improving its durability. In particular, it is preferable that the RF tag be positioned radially inward of the tire's maximum width and radially outward of the bead core of the bead portion. This improves the durability of the RF tag, and communication between the RF tag and a reader is less likely to be obstructed by the bead core, improving the RF tag's communication performance. Furthermore, when the side rubber is composed of multiple rubber members of the same or different types adjacent to each other in the tire radial direction, the RF tag may be sandwiched between the multiple rubber members that make up the side rubber.

[0071] The RF tag may be disposed sandwiched between the bead filler and a member adjacent to the bead filler. This allows the RF tag to be disposed in a position where strain is less likely to concentrate due to the bead filler. Therefore, the load on the RF tag can be reduced. This improves the durability of the RF tag. The RF tag may be disposed sandwiched between the bead filler and the carcass, for example. The portion of the carcass that sandwiches the RF tag together with the bead filler may be located on the outer side of the bead filler in the tire width direction, or on the inner side of the bead filler in the tire width direction. When the portion of the carcass that sandwiches the RF tag together with the bead filler is located on the outer side of the bead filler in the tire width direction, the load on the RF tag due to impact or damage from the outside of the tire in the tire width direction can be further reduced. This improves the durability of the RF tag. The bead filler may also have a portion disposed adjacent to the side rubber. In this case, the RF tag may be disposed by being sandwiched between the bead filler and the side rubber. Furthermore, the bead filler may have a portion disposed adjacent to the rubber chafer. In this case, the RF tag may be disposed by being sandwiched between the bead filler and the rubber chafer.

[0072] The RF tag may be disposed, for example, sandwiched between the rubber chafer and the side rubber. In this way, the RF tag can be disposed in a position where the placement of the rubber chafer makes it less likely for distortion to concentrate. This reduces the load on the RF tag. This improves the durability of the RF tag. The RF tag may be disposed, for example, sandwiched between the rubber chafer and the carcass. In this way, it reduces the load on the RF tag due to impact or damage from the rim. This improves the durability of the RF tag.

[0073] The RF tag may be sandwiched between the wire chafer and another adjacent member on the inner or outer side of the wire chafer in the tire width direction. This makes it difficult for the position of the RF tag to fluctuate when the tire deforms. This reduces the load applied to the RF tag when the tire deforms. This improves the durability of the RF tag. The other adjacent member on the inner or outer side of the wire chafer in the tire width direction may be, for example, a rubber member such as a rubber chafer. Furthermore, the other adjacent member on the inner or outer side of the wire chafer in the tire width direction may be, for example, a carcass.

[0074] A belt reinforcing layer may be further provided on the radially outer side of the belt. For example, the belt reinforcing layer may be formed by winding a cord made of polyethylene terephthalate continuously in a spiral shape in the circumferential direction of the tire. Here, the cord has a diameter of 6.9 × 10 -2 The belt reinforcement layer may be formed by applying an adhesive treatment under a tension of 100 N / tex or more, and have an elastic modulus of 2.5 mN / dtex·% or more when measured at 160°C with a load of 29.4 N. Furthermore, the belt reinforcement layer may be arranged to cover the entire belt or only both ends of the belt. Furthermore, the winding density per unit width of the belt reinforcement layer may vary depending on the position in the width direction. This makes it possible to reduce road noise and flat spots without reducing high-speed durability. [Industrial Applicability]

[0075] The tire according to the present invention can be suitably used for any type of tire, for example, a tire for a passenger car, and in particular, a racing / sports tire that can be used not only in races but also on general roads. Contribution to the Sustainable Development Goals (SDGs) led by the United Nations

[0076] The SDGs have been proposed to realize a sustainable society. One embodiment of the present invention is thought to be a technology that can contribute to "No. 12 Responsible Consumption and Production" and "No. 13 Take concrete measures against climate change." [Explanation of symbols]

[0077] 10: Tires, 1: tread surface, 2: Circumferential groove, 21: 1st circumferential groove (circumferential groove), 22: 2nd circumferential groove (circumferential groove), 3: Rib, 31: First rib (rib), 32: Second rib (rib), 32e: outer end portion of the second rib in the tire width direction; 33: third rib (rib); 4: Lug groove, 41: First lug groove (lug groove), 42: Second lug groove (lug groove), 5: Notch, 51: First notch (notch), 52: Second notch (notch), 53: Third notch (notch), 6: Sidewall part, 91: Communication equipment, CD: Circumferential direction of tire, CL: Equatorial plane of tire, IN: Inside of vehicle OUT: Outside of the vehicle, TE: Tread edge, TW: Tread width, WD: tire width direction, WG1: groove width of first circumferential groove, WG2: groove width of second circumferential groove, WR1: rib width of first rib, WR2: Rib width of the second rib, WR3: Rib width of the third rib

Claims

1. A tire having, on a tread surface, two circumferential grooves extending in a tire circumferential direction and three ribs defined by the two circumferential grooves, The two circumferential grooves are disposed on the inner side of the tire equatorial plane when mounted on a vehicle, When the two circumferential grooves are referred to as a first circumferential groove and a second circumferential groove in order from the vehicle mounting inner side, and the three ribs are referred to as a first rib, a second rib, and a third rib in order from the vehicle mounting inner side, A tire having a relationship in which the groove width of the second circumferential groove is smaller than the groove width of the first circumferential groove, and the rib width of the first rib is smaller than the rib width of the second rib and smaller than the rib width of the third rib.

2. The tire according to claim 1 , wherein the third rib is provided with a plurality of second lug grooves spaced apart in the tire circumferential direction, the second lug grooves extending in the tire width direction and having both ends terminating within the third rib.

3. The first rib is provided with a plurality of first notches that open into the first circumferential groove and are spaced apart in the tire circumferential direction, The second rib is provided with a plurality of second notches that open into the first circumferential groove and are spaced apart in the tire circumferential direction, The tire according to claim 2 , wherein the third rib is provided with a plurality of third notches that open into the second circumferential groove and are spaced apart in the tire circumferential direction.

4. The tire according to claim 3, wherein the first rib is provided with a plurality of first lug grooves spaced apart in the tire circumferential direction, the first lug grooves extending in the tire width direction and having one end opening at a tread end on an inner side mounted on a vehicle.

5. The tire according to claim 3 , wherein the second lug groove and the third notch are arranged so as not to overlap each other when viewed in the tire width direction.

6. The tire according to claim 4 , wherein the first lug groove is arranged so as not to overlap the first notch and the second notch when viewed in the tire width direction.

7. 5. The tire according to claim 4, wherein among the first lug grooves, the first notch, the second notch, the third notch, and the second lug grooves, the first lug grooves, the first notch, the second notch, the third notch, and the second lug grooves that are adjacent to each other in the tire width direction are arranged so as not to overlap each other when viewed in the tire width direction.

8. The tire according to claim 4 , wherein the first lug groove and the first notch are arranged to overlap each other when viewed in the tire circumferential direction.

9. a groove width of the first circumferential groove and a groove width of the second circumferential groove are both 6 to 11% of a tread width, The tire according to any one of claims 1 to 8, wherein a rib width of the first rib, a rib width of the second rib, and a rib width of the third rib are 10% or less, 20% or less, and 60% or less of a tread width, respectively.

Images