tire

Abstract

To provide a tire which improves wet performance and noise performance.SOLUTION: A tire has a tread part 2 having a specified mounting direction to a vehicle. A plurality of land parts 4 of the tread part 2 includes a first shoulder land part 11 including a first tread end T1, and a second shoulder land part 15 including a second tread end T2. On the first shoulder land part 11, a plurality of first shoulder sipes 21 extending in a tire radial direction are provided. On the second shoulder land part 15, a plurality of second shoulder sipes 50 extending in the tire radial direction are provided. The total number of the second shoulder sipes 50 are larger than the total number of the first shoulder sipes 21.SELECTED DRAWING: Figure 1

Description

[Technical field]

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

[0002] The following Patent Document 1 proposes a pneumatic tire having inner lug grooves, outer lug grooves, and intermediate slots in the shoulder land portion. The pneumatic tire uses these lug grooves and slots to suppress heel-and-toe wear in the shoulder land portion while maintaining drainage performance, thereby improving noise performance. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-132181 A Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, with the increasing performance of vehicles, there has been a demand for tires with further improved wet performance and noise performance. On the other hand, the pneumatic tire of Patent Document 1 has a relatively large pumping noise, and there is room for improvement in noise performance.

[0005] The present invention has been devised in view of the above circumstances, and has as its main object to provide a tire with improved wet performance and noise performance. [Means for solving the problem]

[0006] The present invention is a tire having a tread portion with a specified orientation when mounted on a vehicle, the tread portion including a first tread edge that is on the outer side of the vehicle when mounted on the vehicle, a second tread edge that is on the inner side of the vehicle when mounted on the vehicle, a plurality of circumferential grooves extending continuously in the circumferential direction of the tire between the first tread edge and the second tread edge, and a plurality of land portions divided by the circumferential grooves, the plurality of land portions including a first shoulder land portion including the first tread edge and a second shoulder land portion including the second tread edge, the first shoulder land portion being provided with a plurality of first shoulder sipes extending in the axial direction of the tire, and the second shoulder land portion being provided with a plurality of second shoulder sipes extending in the axial direction of the tire, and the total number of the second shoulder sipes is greater than the total number of the first shoulder sipes.

[0007] In the tire of the present invention, the total number of the second shoulder sipes is desirably 1.5 to 2.5 times the total number of the first shoulder sipes.

[0008] In the tire of the present invention, it is preferable that only sipes are provided in the first shoulder land portion and the second shoulder land portion.

[0009] In the tire of the present invention, it is preferable that the first shoulder sipes and the second shoulder sipes are inclined in the same direction relative to the tire axial direction.

[0010] In the tire of the present invention, it is desirable that a maximum angle of the first shoulder sipe with respect to the tire axial direction be larger than a maximum angle of the second shoulder sipe with respect to the tire axial direction.

[0011] In the tire of the present invention, it is preferable that the first shoulder sipe completely traverses the first shoulder land portion in the tire axial direction.

[0012] In the tire of the present invention, it is preferable that the first shoulder sipe includes a portion where the angle with respect to the tire axial direction increases toward the tire equator.

[0013] In the tire of the present invention, it is preferable that the second shoulder sipe extends linearly.

[0014] In the tire of the present invention, it is desirable that the second shoulder sipes include a transverse second shoulder sipe that completely crosses the second shoulder land portion in the tire axial direction, and an interrupted second shoulder sipe that extends at least from the second tread end in the tire axial direction and has an interrupted end within the second shoulder land portion.

[0015] In the tire of the present invention, the length in the tire axial direction of the interrupted second shoulder sipe is desirably 50% to 90% of the width in the tire axial direction of the second shoulder land portion.

[0016] In the tire of the present invention, the circumferential groove includes a first groove wall and a second groove wall facing each other, the first groove wall is provided with a plurality of first recesses recessed outward in the groove width direction from a groove edge of the circumferential groove where the tread surface of the tread portion appears, and the second groove wall is provided with a plurality of second recesses recessed outward in the groove width direction from a groove edge of the circumferential groove where the tread surface of the tread portion appears, the first recesses and the second recesses each gradually decrease in recession amount from the groove edge to both sides in the tire circumferential direction from a deepest portion recessed furthest outward in the groove width direction, and the land portion adjacent to the circumferential groove is provided with a plurality of sipes in the tire circumferential direction communicating with the circumferential groove, and it is preferable that one each of the first recesses and the second recesses is provided within a length 1.0 to 3.0 times the pitch length of the sipe. Effect of the Invention

[0017] By adopting the above-mentioned configuration, the tire of the present invention can improve wet performance and noise performance. [Brief description of the drawings]

[0018] [Figure 1] 1 is a development view of a tread portion showing one embodiment of the present invention. [Diagram 2] FIG. 2 is an enlarged view showing the shape of the contact surface of the tread portion when the tread portion contacts the ground. [Diagram 3] FIG. 2 is an enlarged view of a first shoulder land portion and a first middle land portion of FIG. [Figure 4] FIG. 4 is a cross-sectional view taken along line AA in FIG. [Diagram 5] 4 is a cross-sectional view taken along line CC in FIG. [Figure 6] FIG. 4 is a cross-sectional view taken along line BB in FIG. [Figure 7] FIG. 4 is a cross-sectional view taken along line DD in FIG. [Figure 8] 2 is an enlarged view of a first middle land portion, a crown land portion, and a second middle land portion of FIG. 1. [Figure 9] FIG. 2 is an enlarged view of the second shoulder land portion of FIG. [Figure 10] 10 is a cross-sectional view taken along line EE in FIG. 9. [Figure 11] 2 is a cross-sectional view taken along the line FF in FIG. 1. [Figure 12] FIG. 2 is a cross-sectional view taken along line GG in FIG. [Figure 13] FIG. 4 is a development view of the tread portion 2 of another embodiment. [Figure 14] FIG. 11 is an enlarged view of a first middle land portion according to another embodiment. [Figure 15] FIG. 11 is an enlarged view of a first middle land portion according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a development view of a tread portion 2 of a tire 1 showing one embodiment of the present invention. The tire 1 of this embodiment is suitably used, for example, as a pneumatic tire for passenger cars. However, the present invention is not limited to such an embodiment, and may be applied to a pneumatic tire for heavy loads and a non-pneumatic tire in which pressurized air is not filled inside the tire.

[0020] 1, a tire 1 of this embodiment has a tread portion 2 whose mounting orientation on a vehicle is specified. The tread portion 2 has a first tread edge T1 intended to be located on the outer side of the vehicle when the tire 1 is mounted on the vehicle, and a second tread edge T2 intended to be located on the inner side of the vehicle when the tire 1 is mounted on the vehicle. The mounting orientation on the vehicle is indicated, for example, by letters or symbols on a sidewall portion (not shown).

[0021] The first tread edge T1 and the second tread edge T2 each correspond to the axially outermost contact position when the tire 1 in a normal state is loaded with 50% of the normal load and contacts a flat surface with a camber angle of 0°.

[0022] "Normal condition" means, in the case of a pneumatic tire for which various standards are established, that the tire is mounted on a normal rim, inflated to the normal internal pressure, and unloaded. In the case of a tire for which various standards are not established or a non-pneumatic tire, the normal condition means a standard use condition according to the intended use of the tire, in which the tire is not mounted on a vehicle and is unloaded. In this specification, unless otherwise specified, the dimensions of each part of the tire are values ​​measured in the normal condition.

[0023] A "genuine rim" is a rim that is defined for each tire by the standard system that includes the standard on which the tire is based. For example, in the case of JATMA, it is called a "standard rim," in the case of TRA, it is called a "Design Rim," and in the case of ETRTO, it is called a "Measuring Rim."

[0024] "Normal internal pressure" is the air pressure set for each tire by each standard in the standard system on which the tire is based. In the case of JATMA, it is the "maximum air pressure." In the case of TRA, it is the maximum value listed in the table "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES." In the case of ETRTO, it is the "INFLATION PRESSURE."

[0025] In the case of a pneumatic tire for which various standards are established, the "normal load" is the load that each standard specifies for each tire in the standard system including the standard on which the tire is based. For JATMA, it is the "maximum load capacity", for TRA, it is the maximum value listed in the table "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES", and for ETRTO, it is the "LOAD CAPACITY". In addition, in the case of a tire for which various standards are not established or a non-pneumatic tire, the "normal load" refers to the load acting on one tire in the standard mounting state of the tire. The "standard mounting state" refers to a state in which the tire is mounted on a standard vehicle according to the intended use of the tire, and the vehicle is stationary on a flat road surface in a drivable state.

[0026] The tread portion 2 has a plurality of circumferential grooves 3 extending continuously in the tire circumferential direction between the first tread edge T1 and the second tread edge T2, and a plurality of land portions 4 divided into the circumferential grooves. The tire 1 of this embodiment is configured as a so-called five-rib tire in which the tread portion 2 includes five land portions 4 divided into four circumferential grooves 3.

[0027] The circumferential grooves 3 include, for example, a first shoulder circumferential groove 5, a second shoulder circumferential groove 8, a first crown circumferential groove 6, and a second crown circumferential groove 7. The first shoulder circumferential groove 5 is provided between a first tread edge T1 and a tire equator C. The second shoulder circumferential groove 8 is provided between a second tread edge T2 and a tire equator C. The first crown circumferential groove 6 is provided between the first shoulder circumferential groove 5 and the tire equator C. The second crown circumferential groove 7 is provided between the second shoulder circumferential groove 8 and the tire equator C.

[0028] The axial distance L1 from the tire equator C to the groove centerline of the first shoulder circumferential groove 5 or the second shoulder circumferential groove 8 is preferably, for example, 25% to 35% of the tread width TW. The axial distance L2 from the tire equator C to the groove centerline of the first crown circumferential groove 6 or the second crown circumferential groove 7 is preferably, for example, 5% to 15% of the tread width TW. The tread width TW is the axial distance from the first tread edge T1 to the second tread edge T2 in the normal state.

[0029] Each of the circumferential grooves 3 in this embodiment extends, for example, linearly in parallel to the tire circumferential direction. Each of the circumferential grooves 3 may extend, for example, in a wavy manner.

[0030] The groove width W1 of each circumferential groove 3 is preferably, for example, 2.0% to 8.0% of the tread width TW. In this embodiment, the first shoulder circumferential groove 5 has the smallest groove width among the four circumferential grooves 3. However, the present invention is not limited to this embodiment. In the case of a pneumatic tire for a passenger car, the depth of each circumferential groove 3 is preferably, for example, 5 to 10 mm.

[0031] The land portion 4 of the present invention includes at least a first shoulder land portion 11 and a second shoulder land portion 15. The first shoulder land portion 11 includes a first tread edge T1. The second shoulder land portion 15 includes a second tread edge T2.

[0032] In this embodiment, the land portion 4 includes a first middle land portion 12, a crown land portion 13, and a second middle land portion 14. The first middle land portion 12 is divided into a first shoulder circumferential groove 5 and a first crown circumferential groove 6, and is adjacent to the first shoulder land portion 11 on the second tread end T2 side. The second middle land portion 14 is divided into a second shoulder circumferential groove 8 and a second crown circumferential groove 7, and is adjacent to the second shoulder land portion 15 on the first tread end T1 side.

[0033] The crown land portion 13 is divided between the first crown circumferential groove 6 and the second crown circumferential groove 7. As a result, the crown land portion 13 is provided between the first middle land portion 12 and the second middle land portion 14. The crown land portion 13 of the present embodiment is provided on the tire equator C.

[0034] Each land portion 4 of this embodiment is provided with a sipe 16. In this specification, a "sipe" refers to a cut element having a small width, and the width between two sipe walls in the main body of the sipe 16 is 1.5 mm or less. The width of the sipe 16 is preferably 0.2 to 1.2 mm, and more preferably 0.5 to 1.0 mm. The sipe 16 may include a widened portion that opens with a width larger than the width, or a flask bottom portion that is larger than the width.

[0035] The first shoulder land portion 11 is provided with a plurality of first shoulder sipes 21 extending in the tire axial direction. The second shoulder land portion 15 is provided with a plurality of second shoulder sipes 50 extending in the tire axial direction. The total number of the second shoulder sipes 50 is greater than the total number of the first shoulder sipes 21. As a result, the number of sipes arranged in the first shoulder land portion 11 on the vehicle outer side is reduced, so that the impact sound (especially the impact sound when the edge of the sipes contacts the ground) of the first shoulder land portion 11, which has a large effect on noise performance, is reduced, and noise performance is improved. On the other hand, the second shoulder land portion 15 on the vehicle inner side has many sipes arranged therein, so that a large friction force can be expected on a wet road surface. In the present invention, it is presumed that the wet performance and noise performance can be improved by such a mechanism.

[0036] In order to improve noise performance and wet performance while maintaining driving stability, the total number of second shoulder sipes 50 is desirably 1.3 times or more, more desirably 1.5 times or more, and even more desirably 1.8 times or more of the total number of first shoulder sipes 21, and is desirably 2.8 times or less, more desirably 2.5 times or less, and even more desirably 2.2 times or less.

[0037] A more detailed configuration of this embodiment will be described below. Each configuration described below shows a specific aspect of this embodiment. Therefore, it goes without saying that the present invention can achieve the above-mentioned effects even if it does not have the configuration described below. In addition, even if any one of the configurations described below is applied alone to the tire of the present invention having the above-mentioned characteristics, an improvement in performance according to each configuration can be expected. Furthermore, when some of the configurations described below are applied in combination, a composite improvement in performance according to each configuration can be expected.

[0038] FIG. 2 shows an enlarged view of the shape of the ground contact surface of the tread portion 2 when the tire is grounded. As shown in FIG. 2, when the tire is assembled to a regular rim with a regular internal pressure, and is placed on a flat surface with a camber angle of 0° under a 50% load condition in which the tire is loaded with 50% of the regular load, the widths of the ground contact surface in the tire axial direction of the first shoulder land portion 11, the first middle land portion 12, the crown land portion 13, the second middle land portion 14, and the second shoulder land portion 15 are W1s, W1m, Wc, W2m, and W2s, respectively, and it is preferable that the following formula (1) is satisfied. In a more preferable embodiment, the tire 1 of this embodiment also satisfies the following formula (2). In such a tire 1, the land portion close to the first tread end T1 has a greater rigidity. Therefore, even when the center of the ground contact surface moves toward the first tread end T1 due to steering, the steering response is stable, and a cornering force is generated linearly with respect to an increase in the steering angle. Therefore, excellent steering stability and ride comfort are obtained. W1m>Wc>W2m…(1) W1s>W1m>Wc>W2m≧W2s…(2)

[0039] Under a 50% load condition, the axial width W1s of the ground contact surface of the first shoulder land portion 11 is preferably 115% to 125% of the axial width Wc of the ground contact surface of the crown land portion 13. This optimizes the rigidity of the first shoulder land portion 11, and in addition to the above-mentioned effects, noise performance can also be improved.

[0040] From the same viewpoint, it is preferable that the axial width W1m of the ground contact surface of the first middle land portion 12 is 101% to 107% of the axial width Wc of the ground contact surface of the crown land portion 13 under a 50% load condition.

[0041] Under a 50% load condition, the axial width W2m of the ground contact surface of the second middle land portion 14 is preferably 90% to 99% of the axial width Wc of the ground contact surface of the crown land portion 13. This improves noise performance when traveling straight. Also, tire vibrations when traveling straight are less likely to be transmitted to the vehicle body, improving ride comfort.

[0042] From the same viewpoint, it is preferable that the axial width W2s of the ground contact surface of the second shoulder land portion 15 is 90% to 99% of the axial width Wc of the ground contact surface of the crown land portion 13 under a 50% load condition.

[0043] As a more preferable aspect, in this embodiment, under a 50% load condition, the width W2m of the second middle land portion 14 is set to be the same as the width W2s of the second shoulder land portion 15. This makes the wear progress of the second middle land portion 14 and the second shoulder land portion 15 uniform, improving uneven wear resistance.

[0044] Fig. 3 shows an enlarged view of the first shoulder land portion 11 and the first middle land portion 12. As shown in Fig. 3, only sipes are provided in the first shoulder land portion 11. This increases the rigidity of the first shoulder land portion 11. In this embodiment, the first shoulder land portion 11 is provided with a plurality of first shoulder sipes 21 extending in the tire axial direction.

[0045] The circumferential pitch length P1 of the first shoulder sipe 21 is, for example, 100% to 130% of the axial tread width W3 of the first shoulder land portion 11. The circumferential pitch length of two sipes is the distance parallel to the circumferential direction of the tire from the center position in the width direction of a cross section of one sipe to the center position of the other sipe. When the distance changes in the axial direction of the tire, the intermediate distance corresponds to the circumferential length of one sipe.

[0046] It is desirable that the first shoulder sipes 21 communicate with at least the first shoulder circumferential groove 5. In this embodiment, the first shoulder sipes 21 extend, for example, from the first shoulder circumferential groove 5 to the first tread edge T1 and completely cross the tread surface of the first shoulder land portion 11. However, the first shoulder sipes 21 are not limited to this form, and may have a discontinuous end within the first shoulder land portion 11.

[0047] The first shoulder sipes 21 are inclined, for example, in a first direction (upward and to the right in each drawing of this specification) with respect to the tire axial direction. The angle of the first shoulder sipes 21 with respect to the tire axial direction is, for example, 5 to 35°. In a more desirable embodiment, the first shoulder sipes 21 include a portion where the angle with respect to the tire axial direction increases toward the second tread edge T2 side. Such first shoulder sipes 21 also exert frictional force in the tire axial direction, improving wet performance.

[0048] An opening width W4 at the tread surface of the first shoulder sipes 21 is, for example, larger than an opening width W5 at the tread surface of the first middle sipes 30. Specifically, the opening width W4 of the first shoulder sipes 21 is, for example, 4.0 to 8.0 mm. The opening width W5 of the first middle sipes 30 is, for example, 2.0 to 6.0 mm. Moreover, the opening width W5 of the first middle sipes 30 is 50% to 90% of the opening width W4 of the first shoulder sipes 21. Such first shoulder sipes 21 and first middle sipes 30 are useful for improving wet performance and noise performance in a well-balanced manner.

[0049] Fig. 4 shows a cross section of the first shoulder sipe 21 taken along line AA in Fig. 3. As shown in Fig. 4, the first shoulder sipe 21 includes a main body portion 21a extending in the tire radial direction and a widened portion 21b that opens at the tread surface of the land portion and has a width greater than that of the main body portion 21a. In this embodiment, the width of the main body portion is, for example, 0.5 to 1.5 mm.

[0050] The widened portion 21b of the first shoulder sipe 21 includes an inclined surface 22 extending from the main body portion 21a to the tread surface. In this embodiment, the inclined surface 22 is flat and inclined at an angle θ1 of 50 to 70° with respect to the tire radial direction. Such widened portion 21b allows the entire surface of the inclined surface 22 to come into contact with the ground when a large ground pressure acts on the land portion, thereby reliably expanding the substantial contact area of ​​the tread portion. Therefore, while improving wet performance, the steering stability and ride comfort can also be improved.

[0051] The depth d1 of the widened portion 21b of the first shoulder sipe 21 is 10% to 30% of the maximum depth d3 of the first shoulder sipe 21, and in a preferable embodiment, is 0.5 to 2.0 mm. The maximum depth d3 of the first shoulder sipe 21 is, for example, 70% to 100% of the depth of the circumferential groove 3.

[0052] The width W6 of the widened portion 21b of the first shoulder sipe 21 (the width along the tread surface in the cross section of the sipe) is, for example, 2.0 to 4.0 mm.

[0053] FIG. 5 shows a cross-sectional view of line CC in FIG. 3. As shown in FIG. 6, the first shoulder sipe 21 includes a shallow bottom portion 23 whose bottom portion is locally raised. The shallow bottom portion 23 in this embodiment is provided, for example, at a communicating portion with the first shoulder circumferential groove 5. The minimum depth d4 of the shallow bottom portion 23 of the first shoulder sipe 21 is 40% to 60% of the maximum depth d3 of the first shoulder sipe 21. The length L3 of the shallow bottom portion 23 in the tire axial direction is 10% to 30% of the width W3 (shown in FIG. 3) of the first shoulder land portion 11 in the tire axial direction. The length L3 of the shallow bottom portion 23 is measured, for example, at the center position in the height direction of the shallow bottom portion 23. The first shoulder sipe 21 having such a shallow bottom portion 23 maintains the rigidity of the first shoulder land portion 11 and improves steering stability.

[0054] As shown in Fig. 3, the first middle land portion 12 includes a first longitudinal edge 12a on the first tread edge T1 side, a second longitudinal edge 12b on the second tread edge T2 side, and a tread surface between the first longitudinal edge 12a and the second longitudinal edge 12b. The first middle land portion 12 is provided with only sipes, which increases the rigidity of the first middle land portion 12. The first middle land portion 12 of this embodiment is provided with a plurality of first middle sipes 30 extending in the tire axial direction.

[0055] Fig. 6 shows a cross-sectional view of the first middle sipe 30 taken along line BB in Fig. 3. As shown in Fig. 6, the first middle sipe 30 includes a main body portion 30a extending in the tire radial direction and a widened portion 30b that opens at the tread surface of the land portion and has a width greater than that of the main body portion 30a. In this embodiment, the width of the main body portion is, for example, 0.5 to 1.5 mm.

[0056] The widened portion 30b of the first middle sipe 30 includes an inclined surface 25 extending from the main body portion 30a to the tread surface. The inclined surface 25 in this embodiment is flat and inclined at an angle θ2 of 30 to 60° with respect to the tire radial direction.

[0057] The depth d2 of the widened portion 30b of the first middle sipe 30 is 15% to 30% of the maximum depth d5 ​​of the first middle sipe 30. The depth d2 of the widened portion 30b of the first middle sipe 30 is, for example, 1.0 to 3.0 mm. In a more desirable embodiment, the depth d1 of the widened portion 21b of the first shoulder sipe 21 is smaller than the depth d2 of the widened portion 30b of the first middle sipe 30. The depth d1 of the widened portion 21b of the first shoulder sipe 21 is 50% to 90% of the depth d2 of the widened portion 30b of the first middle sipe 30, and preferably 60% to 80%.

[0058] The width W8 of the widened portion 30b of the first middle sipe 30 (the width along the tread surface in the cross section of the sipe) is, for example, 1.0 to 3.0 mm.

[0059] The first middle sipes 30 include an outer first middle sipe 31 extending from the first longitudinal edge 12a and having an interrupted end 31a within the first middle land portion 12, and an inner first middle sipe 32 extending from the second longitudinal edge 12b and having an interrupted end 32a within the first middle land portion 12.

[0060] The first middle sipes 30 extend linearly in a tread plan view. The first middle sipes 30 are inclined in a first direction with respect to the tire axial direction. More specifically, the outer first middle sipes 31 and the inner first middle sipes 32 each extend linearly in a tread plan view and are inclined in a first direction with respect to the tire axial direction.

[0061] The angle of the outer first middle sipes 31 with respect to the tire axial direction and the angle of the inner first middle sipes 32 with respect to the tire axial direction are each preferably 20° or more, more preferably 25° or more, and preferably 45° or less, more preferably 40° or less. Such outer first middle sipes 31 and inner first middle sipes 32 provide well-balanced frictional forces in the tire axial direction and the tire circumferential direction.

[0062] The angle difference between the outer first middle sipes 31 and the inner first middle sipes 32 is preferably 10° or less, more preferably 5° or less, and in this embodiment, they are arranged parallel to each other. Such outer first middle sipes 31 and inner first middle sipes 32 can suppress uneven wear of the first middle land portion 12.

[0063] The outer first middle sipes 31 and the inner first middle sipes 32 are each interrupted without crossing the axial center position of the first middle land portion 12. The axial length La of the outer first middle sipes 31 is 20% or more, more preferably 25% or more, and preferably 45% or less, and more preferably 40% or less of the axial width W7 of the first middle land portion 12. Similarly, the axial length Lc of the inner first middle sipes 32 is 20% or more, more preferably 25% or more, and preferably 45% or less, and more preferably 40% or less of the axial width W7 of the first middle land portion 12. Such outer first middle sipes 31 and inner first middle sipes 32 can improve ride comfort and noise performance while maintaining steering stability.

[0064] The end 31a of the outer first middle sipe 31 and the end 32a of the inner first middle sipe 32 are misaligned in the tire circumferential direction. The distance Lb in the tire circumferential direction between the end 31a of the outer first middle sipe 31 and the end 32a of the inner first middle sipe 32 is, for example, 50% or less of one pitch length P2 of the first middle sipe 30 in the tire circumferential direction, and desirably 25% to 40%. In a more desirable embodiment, the distance Lb is in the range of the following formula (3). This makes it easier for the pitch sound of each sipe to become white noise, improving noise performance. Lb = 2La ± 1 (mm)…(3)

[0065] The pitch length P2 of the first middle sipes 30 is set to, for example, 80% to 120% of the pitch length P1 of the first shoulder sipes 21, and in a more preferable embodiment, these are set to be the same.

[0066] In this embodiment, the outer first middle sipes 31 communicate with the first shoulder circumferential groove 5. In addition, in a plan view of the tread, the widened portion of the outer first middle sipes 31 overlaps with a region obtained by extending the widened portion 21b of the first shoulder sipes 21 along its length direction. As a result, the outer first middle sipes 31 and the first shoulder sipes 21 cooperate to further improve wet performance.

[0067] The first middle sipes 30 have a constant depth in the length direction. More specifically, the outer first middle sipes 31 and the inner first middle sipes 32 each have a constant depth in the length direction. The depth of the inner first middle sipes 32 is, for example, 70% to 100% of the depth of the circumferential groove 3. The maximum depth of the outer first middle sipes 31 is smaller than the maximum depth of the inner first middle sipes 32. The maximum depth of the outer first middle sipes 31 is 30% to 70% of the maximum depth of the inner first middle sipes 32, and in a desirable embodiment, is 1.0 to 2.5 mm.

[0068] 6 may be applied to the outer first middle sipes 31 and the inner first middle sipes 32. Such outer first middle sipes 31 and inner first middle sipes 32 improve noise performance by converting the pitch sound of each sipe into white noise, and also improve ride comfort and handling stability in a well-balanced manner.

[0069] As shown in Fig. 3, the first middle land portion 12 is provided with, for example, a first longitudinal sipe 33 extending in the tire circumferential direction. In this embodiment, the first longitudinal sipe 33 extends continuously in the tire circumferential direction. Such a first longitudinal sipe 33 provides a friction force in the tire axial direction during wet driving. Further embodiments of the first longitudinal sipe 33 will be described later.

[0070] The first longitudinal sipes 33 are provided, for example, in the central region when the first middle land portion 12 is divided into thirds in the axial direction. The axial distance from the first longitudinal sipes 33 to the axial center position of the first middle land portion 12 is preferably 10% or less of the axial width W7 of the first middle land portion 12, and more preferably 5% or less. Such an arrangement of the first longitudinal sipes 33 can suppress uneven wear of the first middle land portion 12.

[0071] Fig. 7 shows a cross-sectional view taken along line DD in Fig. 3. As shown in Fig. 7, the first longitudinal sipe 33 is configured, for example, to have a constant width from the opening end toward the bottom.

[0072] 8 shows an enlarged view of the first middle land portion 12, the crown land portion 13, and the second middle land portion 14. As shown in FIG. 8, the crown land portion 13 includes a first longitudinal edge 13a on the first tread end T1 side, a second longitudinal edge 13b on the second tread end T2 side, and a tread surface between the first longitudinal edge 13a and the second longitudinal edge 13b. Similarly, the second middle land portion 14 includes a first longitudinal edge 14a on the first tread end T1 side, a second longitudinal edge 14b on the second tread end T2 side, and a tread surface between the first longitudinal edge 14a and the second longitudinal edge 14b.

[0073] The crown land portion 13 includes an outer ground contact surface 36 located closer to the first tread edge T1 than the tire equator C, and an inner ground contact surface 37 located closer to the second tread edge T2 than the tire equator C. In this embodiment, when the axial widths of the outer ground contact surface 36 and the inner ground contact surface 37 are Wco and Wci, respectively, the following formula (4) is satisfied. Such a crown land portion 13 is useful for improving steering stability. Wco>Wci…(4)

[0074] The axial width Wco of the outer ground contact surface 36 is, for example, 51% to 60%, and preferably 51% to 55%, of the axial width W9 of the ground contact surface of the crown land portion 13. This suppresses uneven wear of the crown land portion 13 and improves steering stability.

[0075] Only sipes are provided in the crown land portion 13. This increases the rigidity of the crown land portion 13.

[0076] The crown land portion 13 is provided with a plurality of crown sipes 40 inclined in a second direction (downward to the right in each drawing of this specification) opposite to the first direction with respect to the tire axial direction. The crown sipes 40 of this embodiment extend linearly and inclined in the second direction. Such crown sipes 40 cooperate with the first middle sipes 30 to provide frictional forces in multiple directions, improving wet performance.

[0077] The circumferential pitch length P3 of the crown sipes 40 is, for example, 80% to 120% of the circumferential pitch length P2 (shown in FIG. 3) of the first middle sipes 30, and in this embodiment, these are set to be the same. Such a sipe arrangement improves uneven wear resistance.

[0078] The angle of the crown sipes 40 with respect to the tire axial direction is desirably 20° or more, more desirably 25° or more, and desirably 45° or less, more desirably 40° or less. The crown sipes 40 provide a well-balanced friction force in the tire circumferential direction and the tire axial direction.

[0079] The crown sipes 40 include outer crown sipes 41 extending from the first longitudinal edge 40a and having an interrupted end 41a within the crown land portion 13, and inner crown sipes 42 extending from the second longitudinal edge 40b and having an interrupted end 42a within the crown land portion 13.

[0080] The angle difference between the outer crown sipes 41 and the inner crown sipes 42 is preferably 10° or less, more preferably 5° or less, and in this embodiment, they are arranged parallel to each other. Such outer crown sipes 41 and inner crown sipes 42 suppress uneven wear of the crown land portion 13.

[0081] The outer crown sipes 41 and the inner crown sipes 42 are each discontinued without crossing the axial center position of the crown land portion 13. The axial length L4 of the outer crown sipes 41 and the axial length L5 of the inner crown sipes 42 are, for example, 20% to 35% of the axial width W9 of the crown land portion 13. Such outer crown sipes 41 and inner crown sipes 42 improve steering stability and ride comfort in a well-balanced manner.

[0082] The end 41a of the outer crown sipe 41 and the end 42a of the inner crown sipe 42 are misaligned in the tire circumferential direction. The distance L6 between the end 41a of the outer crown sipe 41 and the end 42a of the inner crown sipe 42 in the tire circumferential direction is preferably smaller than the distance Lb between the end 31a of the outer first middle sipe 31 and the end 32a of the inner first middle sipe 32 in the tire circumferential direction. Specifically, the distance L6 is preferably 70% or less, more preferably 60% or less, and preferably 30% or more, more preferably 40% or more of the distance Lb. Such an arrangement of sipes converts the pitch sound of each sipe into white noise, improving noise performance.

[0083] The outer crown sipes 41 and the inner crown sipes 42 each have a constant depth in the length direction. The depth of the inner crown sipes 42 is, for example, 70% to 100% of the depth of the circumferential groove 3. The maximum depth of the outer crown sipes 41 is smaller than the maximum depth of the inner crown sipes 42. The maximum depth of the outer crown sipes 41 is 30% to 70% of the maximum depth of the inner crown sipes 42, and in a desirable embodiment, is 1.0 to 2.5 mm.

[0084] 6 may be applied to the outer crown sipes 41 and the inner crown sipes 42. Therefore, the description thereof will be omitted here.

[0085] Only sipes are provided in the second middle land portion 14. This increases the rigidity of the second middle land portion 14.

[0086] A plurality of second middle sipes 45 inclined in the second direction with respect to the tire axial direction are provided in the second middle land portion 14. The second middle sipes 45 of the present embodiment extend linearly and inclined in the second direction.

[0087] A one-pitch length P4 of the second middle sipes 45 in the tire circumferential direction is, for example, 80% to 120% of a one-pitch length P3 of the crown sipes 40 in the tire circumferential direction, and in this embodiment, these are set to be the same. Such a sipe arrangement improves uneven wear resistance.

[0088] The angle of the second middle sipes 45 with respect to the tire axial direction is desirably 20° or more, more desirably 25° or more, and desirably 45° or less, more desirably 40° or less. The crown sipes 40 provide a well-balanced friction force in the tire circumferential and axial directions.

[0089] The second middle sipes 45 include an outer second middle sipe 46 extending from the first longitudinal edge 14a and having an interrupted end 46a within the crown land portion 13, and an inner second middle sipe 47 extending from the second longitudinal edge 14b and having an interrupted end 47a within the crown land portion 13.

[0090] The angle difference between the outer second middle sipes 46 and the inner second middle sipes 47 is preferably 10° or less, more preferably 5° or less, and in this embodiment, they are arranged parallel to each other. Such outer second middle sipes 46 and inner second middle sipes 47 suppress uneven wear of the second middle land portion 14.

[0091] The outer second middle sipes 46 and the inner second middle sipes 47 are each interrupted without crossing the axial center position of the second middle land portion 14. The axial length L7 of the outer second middle sipes 46 and the axial length L8 of the inner second middle sipes 47 are, for example, greater than the length L4 of the outer crown sipes 41 and the length L5 of the inner crown sipes 42. Specifically, the length L7 of the outer second middle sipes 46 and the length L8 of the inner second middle sipes 47 are 25% to 35% of the axial width W10 of the second middle land portion 14. Such outer second middle sipes 46 and inner second middle sipes 47 are useful for improving wet performance and ride comfort.

[0092] The end 46a of the outer second middle sipe 46 and the end 47a of the inner second middle sipe 47 are misaligned in the tire circumferential direction. The distance L9 between the end 46a of the outer second middle sipe 46 and the end 47a of the inner second middle sipe 47 in the tire circumferential direction is smaller than the distance Lb between the end 31a of the outer first middle sipe 31 and the end 32a of the inner first middle sipe 32 in the tire circumferential direction, for example, and is preferably smaller than the distance L6 between the end 41a of the outer crown sipe 41 and the end 42a of the inner crown sipe 42 in the tire circumferential direction. Specifically, the distance L9 is preferably 80% or less, more preferably 70% or less, and preferably 40% or more, more preferably 50% or more of the distance L6. Such an arrangement of sipes optimizes the rigidity balance of each land portion and improves the steering stability of wet performance in a well-balanced manner.

[0093] The outer second middle sipes 46 and the inner second middle sipes 47 each have a constant depth in the length direction. The depth of the inner second middle sipes 47 is, for example, 70% to 100% of the depth of the circumferential groove 3. The maximum depth of the outer second middle sipes 46 is smaller than the maximum depth of the inner second middle sipes 47. The maximum depth of the outer second middle sipes 46 is 30% to 70% of the maximum depth of the inner second middle sipes 47, and in a desirable embodiment, is 1.0 to 2.5 mm. Such outer crown sipes 41 and inner crown sipes 42 improve noise performance by converting the pitch sound of each sipe into white noise, and improve ride comfort and handling stability in a well-balanced manner.

[0094] 6 may be applied to the outer second middle sipes 46 and the inner second middle sipes 47. Therefore, the description thereof will be omitted here.

[0095] The second middle land portion 14 is provided with, for example, second longitudinal sipes 48 extending in the tire circumferential direction. In this embodiment, the second longitudinal sipes 48 extend continuously in the tire circumferential direction. The second longitudinal sipes 48 have a cross-sectional shape similar to that of the above-mentioned first longitudinal sipes 33. Such second longitudinal sipes 48 provide frictional force in the tire axial direction.

[0096] The second longitudinal sipes 48 are provided, for example, in the central region when the second middle land portion 14 is divided into thirds in the axial direction. The axial distance from the second longitudinal sipes 48 to the axial center position of the second middle land portion 14 is preferably 10% or less of the axial width W10 of the second middle land portion 14, and more preferably 5% or less.

[0097] Fig. 9 shows an enlarged view of the second shoulder land portion 15 of Fig. 1. As shown in Fig. 9, only sipes are provided in the second shoulder land portion 15. This increases the rigidity of the second middle land portion 14.

[0098] The second shoulder land portion 15 is provided with, for example, a plurality of second shoulder sipes 50 extending in the tire axial direction.

[0099] A one-pitch length P5 of the second shoulder sipes 50 in the tire circumferential direction is, for example, 30% to 70% of a one-pitch length P4 (shown in FIG. 8) of the second middle sipes 45 in the tire circumferential direction.

[0100] The second shoulder sipes 50 are inclined, for example, in a first direction. That is, the first shoulder sipes 21 and the second shoulder sipes 50 are inclined in the same direction with respect to the tire axial direction. The second shoulder sipes 50 of this embodiment extend linearly and inclined in the first direction.

[0101] The angle of the second shoulder sipes 50 relative to the tire axial direction is, for example, 20° or less, preferably 15° or less, and more preferably 10° or less. As a result, in this embodiment, the maximum angle of the first shoulder sipes 21 relative to the tire axial direction is greater than the maximum angle of the second shoulder sipes 50 relative to the tire axial direction. Such an arrangement of sipes further improves noise performance.

[0102] 4 can be applied to the cross-sectional shape of the first shoulder sipes 21 described in Fig. 4. Therefore, the description thereof will be omitted here.

[0103] The second shoulder sipes 50 include, for example, a transverse second shoulder sipe 51 that completely crosses the second shoulder land portion 15 in the tire axial direction, and an interrupted second shoulder sipe 52 that extends in the tire axial direction from at least the second tread end T2 and has an interrupted end within the second shoulder land portion 15.

[0104] The interrupted second shoulder sipes 52 have a greater axial length than any of the first middle sipes 30, the crown sipes 40, and the second middle sipes 45. The axial length L10 of the second shoulder sipes 50 is preferably 50% or more, more preferably 60% or more, and preferably 90% or less, more preferably 80% or less of the axial width W11 of the second shoulder land portion 15. Such interrupted second shoulder sipes 52 improve wet performance and noise performance in a well-balanced manner.

[0105] FIG. 10 shows a cross-sectional view of line EE in FIG. 9. As shown in FIG. 10, the transverse second shoulder sipe 51 includes a shallow bottom portion 53 whose bottom portion is locally raised. The shallow bottom portion 53 in this embodiment is provided, for example, at a communicating portion with the second shoulder circumferential groove 8. The shallow bottom portion 53 of the second shoulder sipe 50 can have the configuration of the shallow bottom portion 23 (shown in FIG. 5) of the first shoulder sipe 21, and the description here is omitted. The transverse second shoulder sipe 51 including such a shallow bottom portion 53 maintains the rigidity of the second shoulder land portion 15 and improves driving stability.

[0106] 1, in this embodiment, only sipes 16 are provided in each of the five land portions 4, and no lateral drainage grooves are provided. This maintains the rigidity of each land portion, and is expected to improve noise performance because pumping noise from the lateral grooves is not generated.

[0107] As a further preferable aspect, in this embodiment, the circumferential groove 3 includes a first groove wall 3a and a second groove wall 3b facing each other, and the first groove wall 3a is provided with a plurality of first recesses 56 recessed outward in the groove width direction from the groove edge of the circumferential groove 3 where the tread surface of the tread portion 2 appears. The second groove wall 3b is provided with a plurality of second recesses 57 recessed outward in the groove width direction from the groove edge of the circumferential groove 3 where the tread surface of the tread portion 2 appears. Such first recesses 56 and second recesses 57 can improve the drainage of the circumferential groove 3 and effectively suppress the hydroplaning phenomenon. In addition, the first recesses 56 and second recesses 57 can be expected to have the effect of attenuating the sound pressure of the noise generated by the circumferential groove 3, and are also useful for improving noise performance.

[0108] It is desirable that the first recess 56 has a gradually decreasing recession amount from the groove edge from the deepest part recessed furthest outward in the groove width direction toward both sides in the tire circumferential direction. Similarly, it is desirable that the second recess 57 has a gradually decreasing recession amount from the groove edge from the deepest part recessed furthest outward in the groove width direction toward both sides in the tire circumferential direction. Such first recess 56 and second recess 57 can prevent the formation of a part with locally reduced rigidity in the land portion, and suppress uneven wear of the land portion.

[0109] In order to further enhance the above-mentioned effects, it is desirable that the first recesses 56 and the second recesses 57 are provided alternately in the tire circumferential direction.

[0110] In this embodiment, the land portion is provided with a plurality of sipes communicating with the circumferential groove 3, and each of the first recessed portion 56 and the second recessed portion 57 is provided within a length 1.0 to 3.0 times the pitch length of the sipes. In other words, the tire circumferential length of each pair of the first recessed portion 56 and the second recessed portion 57 is 1.0 to 3.0 times the pitch length of the sipes. This improves noise performance while maintaining the rigidity of the land portion.

[0111] Fig. 11 shows a cross-sectional view taken along line FF in Fig. 1. Fig. 12 shows a cross-sectional view taken along line GG in Fig. 1. As shown in Figs. 11 and 12, the first groove wall 3a and the second groove wall 3b have substantially the same shape. Furthermore, the first recess 56 and the second recess 57 have substantially the same shape. Therefore, the configuration of the first groove wall 3a described below can be applied to the second groove wall 3b. Furthermore, the configuration of the first recess 56 can be applied to the second recess 57.

[0112] The first groove wall 3a includes an outer portion 18 that extends from the groove edge of the circumferential groove 3 toward the inside in the tire radial direction, at an incline so as to reduce the groove width. The first groove wall 3a also includes an inner portion 19 that extends from the outer portion 18 toward the inside in the tire radial direction, at an incline so as to increase the groove width, and is continuous with the groove bottom. This inner portion 19 forms the bottom surface of the first recess 56.

[0113] The height h1 of the first recess 56 in the tire radial direction is, for example, 30% to 70%, and preferably 40% to 60%, of the total depth d6 of the circumferential groove 3. Such a first recess 56 can improve wet performance and noise performance while suppressing uneven wear of the land portion.

[0114] From the same viewpoint, the depth d7 of the first recess 56 is, for example, 1.0 to 3.0 mm, and preferably 1.5 to 2.5 mm. The depth d7 corresponds to the distance in the groove width direction (the direction parallel to the tread surface) from the first groove wall 3a where the first recess 56 is not provided to the deepest part of the first recess 56. It goes without saying that the height h1 and depth d7 of the first recess 56 described above can be applied to the second recess 57.

[0115] Hereinafter, other embodiments of the present invention will be described. In the drawings showing the other embodiments, the elements already described are given the same reference numerals as those described above, and the above-described configurations can be applied.

[0116] Fig. 13 shows a development view of a tread portion 2 of another embodiment. As shown in Fig. 13, in this embodiment, the first middle land portion 12, the crown land portion 13, and the second middle land portion 14 have the same width in the tire axial direction. The tire axial width W12 is, for example, 10% to 20% of the tread width TW.

[0117] In this embodiment, the first shoulder land portion 11 and the second shoulder land portion 15 have the same width in the tire axial direction. The tire axial width W13 is, for example, 15% to 20% of the tread width TW.

[0118] In the embodiment of FIG. 13, by forming the land portion as described above, the uneven wear resistance of the tread portion 2 can be further improved.

[0119] FIG. 14 shows an enlarged view of the first middle land portion 12 of another embodiment. As shown in FIG. 14, the first longitudinal sipes 33 provided in the first middle land portion 12 extend in a zigzag pattern in the tire circumferential direction. The first longitudinal sipes 33 may extend in a wavy pattern with a smooth curve, for example. The amplitude A1 (peak-to-peak value) of the first longitudinal sipes 33 in the tire axial direction is, for example, 1.0% to 8.0% of the width W7 of the first middle land portion 12 in the tire axial direction. The first longitudinal sipes 33 extend in a zigzag pattern so that one period is equal to two pitches of the first middle sipes 30. Such first longitudinal sipes 33 can also provide friction in the tire circumferential direction.

[0120] Fig. 15 shows an enlarged view of the first middle land portion 12 of still another embodiment. As shown in Fig. 15, the first longitudinal sipes 33 provided in this first middle land portion 12 extend intermittently in the tire circumferential direction. That is, the first longitudinal sipes 33 are composed of a plurality of longitudinal sipe pieces 54 arranged in the tire circumferential direction. The tire circumferential length L11 of one longitudinal sipe piece 54 is, for example, 20% to 60% of one pitch length P2 of the first middle sipes 30 in the tire circumferential direction. Such first longitudinal sipes 33 can provide frictional force in the tire axial direction while maintaining the rigidity of the first middle land portion 12.

[0121] The configuration of the first longitudinal sipes 33 shown in FIGS. 14 and 15 can also be applied to the second longitudinal sipes 48 provided in the second middle land portion 14.

[0122] Although the tire according to one embodiment of the present invention has been described in detail above, the present invention is not limited to the above specific embodiment and can be modified and carried out in various aspects. EXAMPLES

[0123] A tire having a size of 235 / 55R19 and the basic pattern shown in Fig. 1 was prototyped based on the specifications in Tables 1 and 2. In addition, as a standard tire (reference tire) for comparing noise performance, a tire having the pattern shown in Fig. 1 and having no widened portion in each sipe was prototyped. The reference tire is substantially the same as the pattern in Fig. 1, except for the above-mentioned points.

[0124] As a comparative example, a tire was produced in which the total number of first shoulder sipes was the same as the total number of second shoulder sipes by excluding the interrupted second shoulder sipes from the pattern in Figure 1. The comparative tire was substantially the same as that shown in Figure 1, except for the above-mentioned points. The wet performance and noise performance of each test tire were tested. The common specifications and test methods of each test tire are as follows. Rim: 19×7.0J Tire pressure: 230kPa Test vehicle: 2000cc displacement, four-wheel drive Tire mounting position: All wheels

[0125] <Wet performance> The wet performance of the test vehicle when it was driven on a wet road surface was evaluated by the driver. The results are rated based on the wet performance of the comparative example being 100, with the higher the value, the better the wet performance.

[0126] <Noise performance> The test vehicle was driven on a dry road surface at 40 to 100 km / h, and the maximum sound pressure of noise inside the vehicle was measured. The results are expressed as an index of the sound pressure reduction amount, which is the difference from the sound pressure of the reference tire, with the sound pressure reduction amount of the comparative example set to 100. The larger this index, the smaller the maximum sound pressure of the noise, indicating excellent noise performance. The test results are shown in Tables 1-2.

[0127] [Table 1]

[0128] [Table 2]

[0129] As a result of the test, it was confirmed that the tires of the examples had improved wet performance and noise performance. [Explanation of symbols]

[0130] 2 Tread section 3 Circumferential groove 4 Land 11 First Shoulder Land Section 15 Second shoulder land section 21 First shoulder sipe 50 Second shoulder sipe T1 First tread edge T2 Second tread edge

Claims

1. A tire having a tread portion with a specified mounting direction on a vehicle, the tread portion includes a first tread edge that is on an outer side of the vehicle when mounted on the vehicle, a second tread edge that is on an inner side of the vehicle when mounted on the vehicle, a plurality of circumferential grooves that extend continuously in the tire circumferential direction between the first tread edge and the second tread edge, and a plurality of land portions that are divided by the circumferential grooves, the plurality of land portions include a first shoulder land portion including the first tread edge and a second shoulder land portion including the second tread edge, The first shoulder land portion is provided with a plurality of first shoulder sipes extending in the tire axial direction, The second shoulder land portion is provided with a plurality of second shoulder sipes extending in the tire axial direction, The total number of the second shoulder sipes is greater than the total number of the first shoulder sipes, the plurality of circumferential grooves include a first shoulder circumferential groove provided between the first tread edge and a tire equator, and a first crown circumferential groove provided between the first shoulder circumferential groove and the tire equator, the plurality of land portions include a first middle land portion divided into the first shoulder circumferential groove and the first crown circumferential groove, the first middle land portion includes a first vertical edge on the first tread end side, The first middle land portion is provided with a plurality of first middle sipes extending in the tire axial direction, The first middle sipe includes a main body portion extending in a tire radial direction and a widened portion that opens at a tread surface of the land portion and has a width larger than that of the main body portion, The first middle sipe includes an outer first middle sipe extending from the first longitudinal edge and having an interrupted end within the first middle land portion, The first shoulder sipe communicates with the first shoulder circumferential groove, The first shoulder sipe includes a main body portion extending in a radial direction of the tire and a widened portion that opens at a tread surface of the land portion and has a width larger than that of the main body portion, In a tread plan view, the widened portion of the outer first middle sipe overlaps with a region obtained by extending the widened portion of the first shoulder sipe along its length direction. tire.

2. 2. The tire according to claim 1, wherein a total number of the second shoulder sipes is 1.5 to 2.5 times a total number of the first shoulder sipes.

3. The tire according to claim 1 , wherein only sipes are provided in the first shoulder land portion and the second shoulder land portion.

4. The tire according to claim 1 , wherein the first shoulder sipe and the second shoulder sipe are inclined in the same direction relative to the tire axial direction.

5. The tire according to claim 1 , wherein a maximum angle of the first shoulder sipe with respect to the tire axial direction is larger than a maximum angle of the second shoulder sipe with respect to the tire axial direction.

6. The tire according to claim 1 , wherein the first shoulder sipe completely traverses the first shoulder land portion in the tire axial direction.

7. The tire according to claim 1 , wherein the first shoulder sipe includes a portion in which an angle with respect to the tire axial direction increases toward the tire equator.

8. The tire according to claim 1 , wherein the second shoulder sipe extends linearly.

9. 9. The tire according to claim 1, wherein the second shoulder sipes include a transverse second shoulder sipe that completely crosses the second shoulder land portion in the tire axial direction, and an interrupted second shoulder sipe that extends in the tire axial direction from at least the second tread edge and has an interrupted end within the second shoulder land portion.

10. The tire according to claim 9, wherein the length in the tire axial direction of the interrupted second shoulder sipe is 50% to 90% of the width in the tire axial direction of the second shoulder land portion.

11. The circumferential groove includes a first groove wall and a second groove wall facing each other, The first groove wall is provided with a plurality of first recesses recessed in a groove width direction outward from a groove edge of the circumferential groove where a tread surface of the tread portion appears, The second groove wall is provided with a plurality of second recesses recessed in a groove width direction outward from a groove edge of the circumferential groove where a tread surface of the tread portion appears, The first recess and the second recess each have a recess amount from the groove edge that gradually decreases from a deepest portion recessed furthest outward in the groove width direction toward both sides in the tire circumferential direction, A plurality of sipes communicating with the circumferential groove are provided in the land portion adjacent to the circumferential groove in the tire circumferential direction, The tire according to any one of claims 1 to 10, wherein the first recessed portion and the second recessed portion are provided one by one within a length that is 1.0 to 3.0 times a pitch length of the sipe.

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