Tire

Abstract

To improve steering stability performance while suppressing noise performance from deteriorating.SOLUTION: A tread part comprises a land part 4 in which a plurality of transverse groove-like elements 7 extending from first ends 7A positioned at a first edge e1 extending in a tire circumferential direction to second ends 7B positioned at a second edge e2 are formed. The transverse groove-like elements 7 are arranged in the tire circumferential direction so that the second end 7B of one transverse groove-like element and the first end 7A of the other transverse groove-like element 7 arranged adjacent to the second end are positioned at the same position in the tire circumferential direction. The transverse groove-like elements 7 include first portions at the first end 7A sides, second portions at the second end 7B sides, and third portions between the first and second portions, where the portions incline in the same direction with respect to the tire circumferential direction. An angle θ3 of the third portion with respect to the tire circumferential direction is smaller than an angle θ1 of the first portion with respect to the tire circumferential direction and an angle θ2 of the second portion with respect to the tire circumferential direction. A length of the third portion is larger than sum of a length of the first portion and a length of the second portion.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] Generally, axially extending sipes and lateral grooves are provided in the tread portion of a tire from the viewpoint of drainage performance and the like (see, for example, Patent Document 1 below). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2020-168946 Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, with the increasing performance and quietness of vehicles, tires are being required to further improve their handling stability and noise performance. On the other hand, sipes and lateral grooves not only reduce the rigidity of the tread, but also generate various noises during driving. Therefore, when arranging sipes and lateral grooves in the tread, sufficient consideration must be given to noise performance and handling stability.

[0005] The present invention has been devised in view of the above circumstances, and has as its main object to provide a tire that can improve steering stability while limiting deterioration in noise performance. [Means for solving the problem]

[0006] The present invention provides a tire having a tread portion, the tread portion comprising at least one land portion, the land portion including a first edge extending in the tire circumferential direction and a second edge extending in the tire circumferential direction, a plurality of lateral groove elements formed in the land portion, each of the plurality of lateral groove elements extending continuously from a first end located at the first edge to a second end located at the second edge and inclined with respect to the tire axial direction and the tire circumferential direction, the plurality of lateral groove elements being arranged in a first arrangement around one circumference of the tire, the first arrangement being such that the second end of one lateral groove element is inclined with respect to the tire axial direction and the tire circumferential direction each of the plurality of lateral groove elements includes a first portion on the side of the first end, a second portion on the side of the second end, and a third portion therebetween, the first portion, the second portion, and the third portion all inclining in the same direction with respect to the tire circumferential direction, an angle θ3 of the third portion with respect to the tire circumferential direction being smaller than an angle θ1 of the first portion with respect to the tire circumferential direction and an angle θ2 of the second portion with respect to the tire circumferential direction, and a length of the third portion being greater than the sum of the lengths of the first portion and the second portion. [Effects of the Invention]

[0007] By adopting the above-described configuration, the tire of the present invention can improve steering stability while limiting deterioration in noise performance. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 2 is a partial development view of a tread portion of the tire according to the embodiment. [Figure 2] FIG. 2 is an enlarged view of a main part of the land portion of FIG. [Figure 3] 2 is a diagram showing the centerline of the lateral groove element (sipe) of FIG. 1. [Figure 4] FIG. 10 is a plan view of a land portion showing another example of a lateral groove element. [Figure 5] FIG. 10 is a plan view of a land portion showing another example of a lateral groove element. [Figure 6]FIG. 10 is a plan view of a land portion showing another example of a lateral groove element. [Figure 7] FIG. 2 is a plan view of the tread portion showing the shape of the contact patch. [Figure 8] FIG. 10 is a plan view of a land portion in which multiple sets of first arrays are formed. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, several embodiments of the present invention will be described with reference to the drawings. The drawings may include exaggerated representations or representations different from the dimensional ratios of the actual structures to facilitate understanding of the present invention. Furthermore, the same or common elements are designated by the same reference numerals throughout the embodiments, and redundant explanations will be omitted.

[0010] FIG. 1 is a partial development view of a tread portion 2 of a tire 1 of this embodiment, and FIG. 2 is an enlarged view of a main portion of FIG. 1. The tire of this embodiment is embodied, for example, as a pneumatic tire. As a pneumatic tire, for example, a tire for a passenger vehicle is suitable, and a radial tire for a passenger vehicle is particularly suitable. The present invention may also be embodied as a tire for a motorcycle or a tire for a heavy load.

[0011] In Fig. 1, the tire 1 is in a normal state. In this specification, the normal state of the tire 1 means that the tire 1 is mounted on a normal rim at a normal internal pressure and is in an unloaded state. Unless otherwise specified, the dimensions of each part of the tire 1 are values ​​measured in this normal state.

[0012] In this specification, a "genuine rim" is a rim that is defined for each tire by a standard system that includes the standard on which the tire is based, such as a "standard rim" for JATMA, a "design rim" for TRA, or a "measuring rim" for ETRTO.

[0013] In this specification, the term "normal internal pressure" refers to the air pressure specified for each tire by the respective standards, including the standards on which the tire is based, and is the "maximum air pressure" in the case of JATMA, the maximum value listed in the table "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES" in the case of TRA, and the "INFLATION PRESSURE" in the case of ETRTO.

[0014] As shown in Fig. 1, the tread portion 2 includes a first tread edge Te1, a second tread edge Te2, and a tread surface 2a between them. The tread surface 2a is intended to come into contact with the ground and is formed of tread rubber. The first tread edge Te1 and the second tread edge Te2 are each the axially outermost edges of the contact patch under normal load conditions.

[0015] In this specification, the "normal load condition" refers to a state in which a normal load is applied to the tire 1 in a normal state and the tire is in contact with a flat surface with a camber angle of zero. Also, in this specification, the "normal load" refers to a load determined for each tire by each standard in a standard system including the standard on which the tire is based, and is the "maximum load capacity" in the case of JATMA, the maximum value listed in the table "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES" in the case of TRA, and the "LOAD CAPACITY" in the case of ETRTO.

[0016] The tread portion 2 has, for example, a plurality of (e.g., three) circumferential grooves 3 formed therein that extend in the tire circumferential direction. The circumferential grooves 3 in this embodiment extend, for example, linearly in parallel to the tire circumferential direction. Although not particularly limited, in order to ensure sufficient drainage during wet driving, the width of the circumferential grooves 3 is, for example, greater than 2 mm, preferably 3 mm or more, and more preferably 4 mm or more. Similarly, the groove depth of the circumferential grooves 3 is, for example, 3 mm or more, preferably 4 mm or more, and more preferably 5 mm or more.

[0017] The tread portion 2 is divided into a plurality of land portions 4 by one or more circumferential grooves 3. In this embodiment, the land portion 4 includes a pair of crown land portions 5 and a pair of shoulder land portions 6 arranged on both axially outer sides of the pair of crown land portions 5.

[0018] In the following, one crown land portion 5 (on the left side in FIG. 1) will be referred to in describing the land portion 4. The other land portions 4 may have the same configuration as that described below, or may have a different configuration.

[0019] The crown land portion 5 includes a first edge e1 extending in the tire circumferential direction and a second edge e2 extending in the tire circumferential direction. In this embodiment, the first edge e1 is an edge of the crown land portion 5 on the side of the first tread edge Te1, and the second edge e2 is an edge of the crown land portion 5 on the side of the second tread edge Te2. The tread surface of the crown land portion 5 is defined between the first edge e1 and the second edge e2.

[0020] A plurality of lateral groove elements 7 inclined with respect to the tire axial direction and the tire circumferential direction are formed in the crown land portion 5. Therefore, each of the plurality of lateral groove elements 7 has a non-zero angle with respect to the tire axial direction and the tire circumferential direction.

[0021] The lateral grooved elements 7 are voids recessed from the ground contact surface of the land portion 4, and are a comprehensive concept including, for example, both sipes and grooves. In the present specification, the examples of Figures 1 and 2 show the case where the lateral grooved elements 7 are sipes. Alternatively, the lateral grooved elements 7 may be grooves.

[0022] In this specification, a "sipe" refers to a slit-shaped gap having a width perpendicular to the longitudinal direction of 2 mm or less, preferably 1.5 mm or less. A sipe functions so that at least a portion of a pair of sipe walls comes into contact with each other when the tire contacts the ground under normal load, for example. Therefore, the sipe minimizes a decrease in the rigidity of the land portion 4, thereby helping to improve steering stability. Furthermore, in this specification, a "groove" refers to a gap having a width in the longitudinal direction and perpendicular thereto, and having a width greater than 2 mm. There is no particular upper limit on the width of the groove, but in the case of passenger car tires, it may be, for example, 10 mm or less. Such grooves help to improve drainage.

[0023] 2, each of the lateral groove elements 7 includes a first end 7A located at the first edge e1 and a second end 7B located at the second edge e2, and extends continuously between them. Therefore, each of the lateral groove elements 7 extends so as to completely cross the crown land portion 5 in the tire axial direction. This divides the land portion 4 into block-shaped land elements 8.

[0024] In the crown land portion 5, a plurality of lateral groove elements 7 are arranged in a first array 10. In this embodiment, one set of first arrays 10 is formed in the crown land portion 5. In a preferred embodiment, only the first arrays 10 (a plurality of lateral groove elements 7) are formed in the crown land portion 5.

[0025] In the first arrangement 10, multiple lateral groove elements 7 are repeatedly arranged around the tire so that the second end 7B of one lateral groove element 7 and the first end 7A of another lateral groove element 7 adjacent to it in the tire circumferential direction are located at the same position in the tire circumferential direction. More specifically, as shown in FIG. 2 , a first position P1 where the center line 7C of one lateral groove element 7 intersects with the first edge e1 and a second position P2 where the center line 7C of another lateral groove element 7 adjacent to the lateral groove element 7 in the tire circumferential direction intersects with the second edge e2 are located at the same position in the tire circumferential direction. However, in consideration of the characteristics of a tire, which is a vulcanized rubber product, the first position P1 and the second position P2 may be shifted by a small distance a in the tire circumferential direction to allow for manufacturing errors. In this case, the distance a is set to 5% or less of the circumferential length La of the groove center line of the lateral groove element 7, preferably 3% or less, and more preferably 1% or less.

[0026] Pitch noise is known as noise generated when a tire is running. An impact force is generated each time a land element 8 separated by lateral groove elements 7 comes into contact with the ground. This impact force periodically vibrates the tread portion 2 and the sidewall portion (not shown), which in turn generates pitch noise. However, in the first arrangement 10 of this embodiment, the pitch of the arrangement of the lateral groove elements 7 relative to the center line 7C of the lateral groove elements 7 is substantially equal to the circumferential length La of the lateral groove elements 7 in the tire circumferential direction. Therefore, in the tire 1 of this embodiment, multiple lateral groove elements 7 come into contact with the ground continuously and uninterruptedly during running, thereby reducing fluctuations in the impact force. Therefore, the tire 1 of this embodiment can improve noise performance by reducing pitch noise.

[0027] FIG. 3 shows a schematic diagram of a lateral groove element 7, with its center line 7C indicated. Each of the multiple lateral groove elements 7 includes a first portion 71 on the side of a first end 7A, a second portion 72 on the side of a second end 7B, and a third portion 73 therebetween. The first portion 71, the second portion 72, and the third portion are all inclined in the same direction relative to the tire circumferential direction. In this embodiment, the first portion 71, the second portion 72, and the third portion are all inclined upward to the right relative to the tire circumferential direction. Such lateral groove elements 7 gradually come into contact with the tire from one longitudinal end to the other, which is advantageous in reducing running noise compared to elements that extend parallel to the tire axial direction.

[0028] 3, the angle θ3 of the third portion 73 with respect to the tire circumferential direction is smaller than the angle θ1 of the first portion 71 with respect to the tire circumferential direction and the angle θ2 of the second portion 72 with respect to the tire circumferential direction. In addition, the length L3 of the third portion 73 is larger than the sum (L1+L2) of the length L1 of the first portion 71 and the length L2 of the second portion 72.

[0029] Regarding the angle of the lateral groove elements 7 relative to the tire circumferential direction, the larger the angle, the more advantageous it is for handling stability. Furthermore, when the vehicle is cornering, the force acting on the first edge e1 and the second edge e2 of the land portion 4 is greater. In this embodiment, the angles θ1 and θ2 of the first portion 71 and the second portion 72 located at both ends of the land portion 4 are greater than the angle θ3 of the third portion 73, thereby improving handling stability. Furthermore, the length L3 of the steeply inclined third portion 73 is greater than the sum (L1 + L2) of the length L1 of the first portion 71 and the length L2 of the second portion 72, making it difficult for each land element 8 to twist during cornering. Due to these effects, the tire 1 of this embodiment has improved handling stability. Note that when the lateral groove elements 7 are sipes as in this embodiment, bending the lateral groove elements 7 as described above allows adjacent land elements 8 to support each other during tire running, further improving handling stability.

[0030] From the viewpoint of more effectively suppressing the torsional deformation of the land element 8, it is desirable that the length L3 of the third portion 73 be large. For example, the length L3 of the third portion 73 is set to be 1.2 times or more, preferably 1.5 times or more, and more preferably 2.0 times or more, the sum (L1 + L2) of the length L1 of the first portion 71 and the length L2 of the second portion 72. Furthermore, from the viewpoint of ensuring sufficient lateral rigidity in the vicinity of the first edge e1 and the second edge e2 of the land portion 4, the length L3 of the third portion 73 is set to be, for example, 3.5 times or less, preferably 3.0 times or less, the sum (L1 + L2). In a particularly desirable example, the length L1 of the first portion 71 and the length L2 of the second portion 72 are equal to each other (L1 = L2). In another example, L1 ≠ L2 may be satisfied.

[0031] The angle θ1 of the first portion 71 and the angle θ2 of the second portion 72 are not particularly limited, but from the viewpoint of improving steering stability, they are, for example, 60 degrees or more, preferably 65 degrees or more, and more preferably 70 degrees or more. The upper limit of the angle θ1 of the first portion 71 and the angle θ2 of the second portion 72 may be less than 90 degrees, but is preferably 85 degrees or less, and more preferably 80 degrees or less. In a particularly desirable example, the angle θ1 and the angle θ2 are equal to each other (θ1 = θ2). In another example, θ1 ≠ θ2 may be satisfied.

[0032] The angle θ3 of the third portion 73 is not particularly limited as long as it is smaller than the angle θ1 of the first portion 71 and the angle θ2 of the second portion 72, but in order to firmly engage adjacent land elements 8 with each other and achieve higher handling stability during cornering, it is preferably 20 degrees or more, more preferably 30 degrees or more, and is preferably 50 degrees or less, more preferably 40 degrees or less.

[0033] 1 and 2, the first portion 71, the second portion 72, and the third portion 73 all extend linearly, and these portions are directly connected without any intervening arc portions. In another example, as shown in FIG. 4, an arc portion 9 with a radius of curvature R may be disposed between the first portion 71 and the third portion 73 and / or between the third portion 73 and the second portion 72. In the example shown in FIG. 4, the lengths of the first portion 71, the second portion 72, and the third portion 73 are determined by imaginary extensions of their respective centerlines and based on the intersections between them.

[0034] FIG. 5 shows a modified example of the lateral groove element 7. In the example of FIG. 5, the width W1 of the first portion 71 and the width W2 of the second portion 72 are smaller than the width of the third portion 73. That is, the widths W1 and W2 of the first portion 71 and the second portion 72, which have relatively large angles θ1 and θ2 with respect to the tire circumferential direction, are smaller than the width W3 of the third portion 73, which has a relatively small angle θ3. In this embodiment, in a cross section of the land portion 4 taken along a plane perpendicular to the contact patch of the land portion 4 and parallel to the tire axial direction, the widths of the first portion 71 and the second portion 72 and the width of the third portion 73 are similar to or equal to each other. This helps to further reduce fluctuations in impact force during tire running and further improve noise performance.

[0035] 6 shows a modified example of the lateral grooved elements 7. In this example, the lateral grooved elements 7 are formed as lateral grooves. The lateral grooved elements 7 of the present invention are not limited to sipes, and may be lateral grooves.

[0036] FIG. 7 shows the contact patch GL under normal load conditions with a virtual line. As shown in FIG. 7, the circumferential length D of the edge GLa of the contact patch GL that crosses the land portion is 20% or less of the circumferential length La of one lateral groove element 7. To further enhance noise reduction, the inventors focused on the relationship between the circumferential length La of the lateral groove element 7 and the circumferential length D of the edge GLa of the contact patch GL. To achieve the impact force fluctuation suppression effect expected from the first arrangement 10, it is most effective for the edge GLa of the contact patch GL that crosses the land portion 4 to be parallel to the tire axial direction. However, in actual tires, the edge GLa of the contact patch GL tends to be arc-shaped, as shown in FIG. 7. Even in such cases, by setting the circumferential length D of the edge GLa of the contact patch GL to 20% or less of the circumferential length La of one lateral groove element 7, the difference in contact timing between the first edge e1 and the second edge e2 of the land portion 4 can be minimized. This further reduces the above-mentioned fluctuation in impact force, and helps to further improve noise performance. In a particularly desirable embodiment, the length D in the tire circumferential direction of the edge GLa of the contact patch GL is set to 10% or less, more preferably 5% or less, of the length La of one of the lateral groove elements 7 in the tire circumferential direction.

[0037] FIG. 8 shows yet another embodiment. In this embodiment, multiple sets of first arrays 10 are formed in each land portion 4. Specifically, two sets are formed: a first array 10A and another first array 10B. In this embodiment, pitch noise is reduced, thereby improving noise performance and steering stability. In this embodiment, the multiple lateral groove elements 7 in the first arrays 10A and 10B are arranged at a pitch equal to the tire circumferential length La (shown in FIG. 2). The multiple first arrays 10A and 10B are offset from each other in the tire circumferential direction by 50% of the pitch. This embodiment helps to reduce the above-mentioned impact force fluctuation and further improve noise performance.

[0038] Although several embodiments of the present invention have been described above, the specific configurations shown in the embodiments and drawings are for the purpose of understanding the contents of the present invention, and the present invention is not limited to the specific configurations shown in the drawings. Furthermore, in the above embodiments, the crown land portion 5 has been described as an example, but the lateral groove elements 7 may be formed in the shoulder land portion 6 instead of the crown land portion 5 (or together with the crown land portion 5). [Example]

[0039] In order to confirm the effects of the present invention, pneumatic radial tires for passenger cars with a tire size of 195 / 65R15 91H (mounted rim: 15x6.0, internal pressure: 230 kPa) based on the specifications in Table 1 were prepared, and tests were conducted on the handling stability and noise performance. The first arrangement of the specifications in Table 1 was applied to all land portions. The internal structure of each tire was the same. The test contents were as follows.

[0040] Noise performance test (actual vehicle evaluation): Test tires were mounted on all four wheels of a test vehicle (a 2000cc front-wheel drive vehicle). The test vehicle was then driven on a dry road at a speed of 40-100 km / h, and the maximum sound pressure of the noise was measured. The results were expressed as an index, with the sound pressure of the comparative example being set at 100, and a smaller value indicates lower running noise (lower sound pressure) and better noise performance.

[0041] Steering stability test: Test tires were mounted on all four wheels of the test vehicle. The test vehicle was then driven on an asphalt circuit course, and the handling stability was evaluated by the driver's senses. The results were scored based on a comparative example being 100, with a higher score indicating better handling stability. The test results are shown in Table 1.

[0042] [Table 1]

[0043] As a result of the test, it was confirmed that the Example had improved handling stability without sacrificing noise performance compared to the Comparative Example.

[0044] [Note] The present invention includes the following aspects.

[0045] [Invention 1] A tire having a tread portion, The tread portion includes at least one land portion, the land portion includes a first edge extending in the tire circumferential direction and a second edge extending in the tire circumferential direction, A plurality of lateral groove elements are formed in the land portion, each of the plurality of lateral groove elements extends continuously from a first end located at the first edge to a second end located at the second edge, and is inclined with respect to the tire axial direction and the tire circumferential direction; the plurality of lateral groove elements are arranged in a first arrangement around one circumference of the tire, the first arrangement is such that the second end of one lateral groove element is at the same position in the tire circumferential direction as the first end of the lateral groove element adjacent thereto in the tire circumferential direction, each of the plurality of lateral groove elements includes a first portion on the side of the first end, a second portion on the side of the second end, and a third portion therebetween; the first portion, the second portion, and the third portion are all inclined in the same direction with respect to the tire circumferential direction, an angle θ3 of the third portion with respect to the tire circumferential direction is smaller than an angle θ1 of the first portion with respect to the tire circumferential direction and an angle θ2 of the second portion with respect to the tire circumferential direction; The length of the third portion is greater than the sum of the length of the first portion and the length of the second portion. tire. [Invention 2] 2. The tire according to claim 1, wherein the lateral groove elements are sipes having a width of 2 mm or less. [Invention 3] 2. The tire according to claim 1, wherein the lateral grooved elements are grooves having a width greater than 2 mm. [Invention 4] The tire according to any one of claims 1 to 3, wherein the width of the first portion and the width of the second portion are smaller than the width of the third portion. [Invention 5] 5. The tire according to any one of claims 1 to 4, wherein the angle θ1 and the angle θ2 are equal to each other. [Invention 6] A tire according to any one of the first to fifth aspects of the present invention, wherein the tire is mounted on a normal rim at a normal internal pressure, and when the tire is in contact with a flat surface under a normal load with a camber angle of zero under normal load, the circumferential length of the edge of the contact surface that crosses the land portion is 20% or less of the circumferential length of one of the lateral groove elements. [Invention 7] The tire according to any one of the first to sixth aspects of the present invention, wherein a plurality of sets of the first arrangement are provided in the land portion. [Invention 8] the angle θ3 of the third portion with respect to the tire circumferential direction is in the range of 20 to 50 degrees, The tire according to any one of claims 1 to 7, wherein angles θ1 and θ2 of the first portion and the second portion with respect to the tire circumferential direction are in the range of 60 degrees or more and less than 90 degrees, respectively. [Invention 9] The tire according to any one of claims 1 to 8, wherein the length L3 of the third portion is 1.2 times or more the sum (L1 + L2) of the length L1 of the first portion and the length L2 of the second portion. [Invention 10] The tire according to any one of claims 1 to 9, wherein the length L3 of the third portion is 3.5 times or less the sum (L1+L2) of the length L1 of the first portion and the length L2 of the second portion. [Invention 11] 11. The tire according to any one of claims 1 to 10, wherein the first portion includes a portion extending linearly, the second portion includes a portion extending linearly, and the third portion includes a portion extending linearly. [Invention 12] 12. The tire according to claim 11, wherein the first portion, the second portion, and the third portion are directly connected to one another without any arc portion therebetween. [Invention 13] 12. The tire according to claim 11, wherein the first portion, the second portion, and the third portion are connected to one another with arc portions interposed therebetween. [Explanation of symbols]

[0046] 1 tire 2 Tread section 4 Land 7. Grooved elements 7A 1st end 7B 2nd end 10 First Array 71 Part 1 72 Part 2 73 Part 3 GL Edge of the ground e1 First edge e2 Second edge

Claims

1. A tire having a tread portion, The tread portion includes at least one land portion, the land portion includes a first edge extending in the tire circumferential direction and a second edge extending in the tire circumferential direction, A plurality of lateral groove elements are formed in the land portion, each of the plurality of lateral groove elements extends continuously from a first end located at the first edge to a second end located at the second edge, and is inclined with respect to the tire axial direction and the tire circumferential direction; the plurality of lateral groove elements are arranged in a first array around one circumference of the tire, the first arrangement is such that the second end of one lateral groove element is positioned at the same position in the tire circumferential direction as the first end of the lateral groove element adjacent thereto in the tire circumferential direction, each of the plurality of lateral grooved elements includes a first portion on the side of the first end, a second portion on the side of the second end, and a third portion therebetween; the first portion, the second portion, and the third portion are all inclined in the same direction with respect to the tire circumferential direction, an angle θ3 of the third portion with respect to the tire circumferential direction is smaller than an angle θ1 of the first portion with respect to the tire circumferential direction and an angle θ2 of the second portion with respect to the tire circumferential direction, the length of the third portion is greater than the sum of the length of the first portion and the length of the second portion; the land portion on which the plurality of lateral groove elements are formed is provided with only the plurality of lateral groove elements, The plurality of lateral grooved elements are grooves having a width greater than 2 mm. tire.

2. The tire of claim 1 , wherein the width of the first portion and the width of the second portion are less than the width of the third portion.

3. The tire according to claim 1 , wherein the angle θ1 and the angle θ2 are equal to each other.

4. 4. The tire according to claim 1, wherein, in a contact patch state in which the tire is mounted on a normal rim at a normal internal pressure and in contact with a flat surface under a normal load with a camber angle of zero, the circumferential length of the edge of the contact patch that crosses the land portion is 20% or less of the circumferential length of one of the lateral groove elements.

5. The tire according to claim 1 , wherein the land portion has a plurality of sets of the first arrangement.

6. the angle θ3 of the third portion with respect to the tire circumferential direction is in the range of 20 to 50 degrees, The tire according to claim 1 , wherein angles θ1 and θ2 of the first portion and the second portion with respect to the tire circumferential direction are in a range of not less than 60 degrees and less than 90 degrees, respectively.

7. 4. The tire according to claim 1, wherein the length L3 of the third portion is 1.2 times or more the sum (L1 + L2) of the length L1 of the first portion and the length L2 of the second portion.

8. The tire according to claim 7, wherein the length L3 of the third portion is 3.5 times or less the sum (L1 + L2) of the length L1 of the first portion and the length L2 of the second portion.

9. 4. The tire of claim 1, wherein the first portion includes a linearly extending portion, the second portion includes a linearly extending portion, and the third portion includes a linearly extending portion.

10. 10. The tire of claim 9, wherein the first portion, the second portion, and the third portion are directly connected to one another without any intervening arc portions therebetween.

11. The tire of claim 9 , wherein the first portion, the second portion, and the third portion are connected to one another with an arc portion interposed therebetween.

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