Tire

Abstract

This invention provides a tire with improved ride comfort and noise performance. A tire has a tread portion (2) that specifies the direction of installation toward a vehicle. Sipes (16) are provided in five land portions (4) of the tread portion (2). The five land portions (4) include: a first shoulder land portion (11), a second shoulder land portion (15), a first intermediate land portion (12), a second intermediate land portion (14), and a crown land portion (13). When a standard inner pressure rim is assembled on a regular rim and a 50% load of standard load is applied with the ground plane at 0° camber, and the widths of the contact surfaces of the first shoulder land portion, the first intermediate land portion, the crown land portion, the second intermediate land portion, and the second shoulder land portion in the tire axial direction are set as W1s, W1m, Wc, W2m, and W2s, respectively, the following formula (1) is satisfied: W1s>W1m>Wc>W2m≥W2s.

Description

Technical Field

[0001] This invention relates to tires. Background Technology

[0002] Patent Document 1 discloses a pneumatic tire configured with a tread comprising five land portions. These land portions include a crown land portion, a pair of intermediate land portions, and a pair of shoulder land portions.

[0003] The aforementioned shoulder land portion has inner lateral grooves, outer lateral grooves, and an intermediate slit extending axially between them. The inner lateral grooves extend axially outward from the shoulder circumferential groove and terminate near the contact patch. The outer lateral grooves extend axially inward from the contact patch and terminate near the shoulder circumferential groove without intersecting with the inner lateral grooves. The intermediate slit terminates axially outward without reaching the shoulder circumferential groove, and also terminates axially outward without reaching the contact patch.

[0004] Therefore, the shoulder land portion of the aforementioned pneumatic tire is continuous along the tire circumference without interruption. Through these features, the aforementioned pneumatic tire can be expected to maintain drainage performance, suppress heel-toe wear on the shoulder land portion, and improve noise performance.

[0005] Patent Document 1: Japanese Patent Application Publication No. 2010-132181

[0006] In recent years, tires have demanded further improvements in ride comfort and noise performance. The inventors, by re-examining the relationship between the widths of the five land portions in a tire tread, recognized the potential to improve these performance aspects, leading to the completion of this invention. Summary of the Invention

[0007] The present invention was made in view of the above problems, and the main objective is to provide a tire that improves ride comfort and noise performance.

[0008] This invention relates to a tire having a tread portion indicating a direction of installation toward a vehicle. The tread portion includes: a first tread end that becomes the outer side of the vehicle during installation; a second tread end that becomes the inner side of the vehicle during installation; four circumferential grooves extending continuously along the tire circumference between the first tread end and the second tread end; and five land portions divided by the circumferential grooves. Each of the five land portions has a sipe. The five land portions include: a first shoulder land portion containing the first tread end; a second shoulder land portion containing the second tread end; and a first intermediate land portion adjacent to the first shoulder land portion. The land portion, the second intermediate land portion adjacent to the second shoulder land portion, and the crown land portion between the first intermediate land portion and the second intermediate land portion, when assembled on a standard inner pressure rim with a standard load of 50% and with a 0° camber angle as the ground plane, satisfy the following formula (1) when the widths of the contact surfaces of the first shoulder land portion, the first intermediate land portion, the crown land portion, the second intermediate land portion, and the second shoulder land portion are respectively set as W1s, W1m, Wc, W2m, and W2s.

[0009] W1s>W1m>Wc>W2m≥W2s…(1).

[0010] The tire of the present invention, by adopting the above-described structure, can improve ride comfort and noise performance. Attached Figure Description

[0011] Figure 1 This is a unfolded view of the tread portion of a tire according to one embodiment of the present invention.

[0012] Figure 2 It is an enlarged view showing the shape of the contact patch when the tire tread touches the ground.

[0013] Figure 3 yes Figure 1 Enlarged view of the first shoulder land portion and the first intermediate land portion.

[0014] Figure 4 yes Figure 3 A sectional view along line AA.

[0015] Figure 5 yes Figure 3 CC-line sectional view.

[0016] Figure 6 yes Figure 3 BB line section view.

[0017] Figure 7 yes Figure 3 DD-line sectional view.

[0018] Figure 8 yes Figure 1 Enlarged view of the first intermediate landmass, the crown landmass, and the second intermediate landmass.

[0019] Figure 9 yes Figure 1 Enlarged view of the second fetal shoulder land area.

[0020] Figure 10 yes Figure 9 EE line section view.

[0021] Figure 11 This is an enlarged view of the first intermediate land portion in other embodiments.

[0022] Figure 12 This is an enlarged view of the first intermediate land portion in other embodiments.

[0023] Figure 13 This is an enlarged view of the first and second shoulder land portions in other embodiments.

[0024] Figure 14 This is an enlarged view of the first and second shoulder land portions in other embodiments.

[0025] Figure 15 This is a unfolded view of the tread area in other embodiments.

[0026] Figure 16 yes Figure 15 Enlarged view of the first intermediate landmass, the crown landmass, and the second intermediate landmass.

[0027] Figure 17 yes Figure 16 Enlarged view of the outer first intermediate tool groove and the inner first intermediate tool groove.

[0028] Figure 18 yes Figure 16 Enlarged view of the outer second intermediate tool groove and the inner second intermediate tool groove.

[0029] Figure 19 yes Figure 15 Enlarged views of the first and second shoulder land areas.

[0030] Figure 20 This is a unfolded diagram of the tread of a reference tire.

[0031] Figure 21 This is a unfolded diagram of the tread of a comparative example tire.

[0032] Explanation of reference numerals in the attached figures: 2…tread portion; 3…circumferential groove; 4…land portion; 11…first shoulder land portion; 12…first intermediate land portion; 13…crown land portion; 14…second intermediate land portion; 15…second shoulder land portion; 16…sipe; T1…first tread end; T2…second tread end. Detailed Implementation

[0033] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. Figure 1 This is a developed view of the tread portion 2 of a tire 1 according to one embodiment of the present invention. The tire 1 of this embodiment is suitable, for example, for use as a pneumatic tire for passenger vehicles. However, the present invention is not limited to this method and can also be applied to pneumatic tires for heavy-duty use and non-air tires that are not filled with pressurized air.

[0034] like Figure 1 As shown, the tire 1 of the present invention has a tread portion 2 that specifies the direction of installation toward a vehicle. The tread portion 2 has a first tread end T1 intended to be located on the outer side of the vehicle when the tire 1 is installed in the vehicle, and a second tread end T2 intended to be located on the inner side of the vehicle when installed in the vehicle. The direction of installation toward the vehicle is indicated, for example, by text or symbols on the sidewall portion (illustration omitted).

[0035] The first tread end T1 and the second tread end T2 are respectively the outermost contact points of the tire axial direction when the tire 1 is loaded with 50% of the standard load in normal condition and the contact plane is taken as 0° camber.

[0036] "Standard condition" refers to the state where, for pneumatic tires of various specifications, the tire and rim are assembled on a standard rim, inflated to standard pressure, and unloaded. For tires without specified specifications or non-pneumatic tires, the above-mentioned standard condition means the standard operating condition corresponding to the tire's intended use, i.e., unloaded and not mounted on a vehicle. In this specification, unless otherwise specified, the dimensions of various parts of the tire are values ​​measured under the above-mentioned standard condition. Furthermore, the structures described in this specification allow for the usual errors inherent in rubber molded products.

[0037] "Standard rim" refers to the rim that specifies the size of each tire within a specification system that includes the tire's specifications. For example, if it is JATMA, it is a "standard rim"; if it is TRA, it is a "Design Rim"; and if it is ETRTO, it is a "Measuring Rim".

[0038] "Standard internal pressure" refers to the air pressure specified for each tire in the specification system, including the specifications on which the tire is based. If it is JATMA, it is the "maximum air pressure". If it is TRA, it is the maximum value recorded in the table "TIRE LOAD LIMITS AT VARIOUSCOLD INFLATION PRESSURES". If it is ETRTO, it is the "INFLATION PRESSURE".

[0039] "Standard load" refers to the load specified for each tire within a specification system, including the specifications the tire is based on, when various sizes of pneumatic tires are defined. For JATMA, it is the "maximum load capacity"; for TRA, it is the maximum value recorded in the table "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES"; and for ETRTO, it is the "LOAD CAPACITY". Furthermore, in the case of tires without specified sizes or non-pneumatic tires, "standard load" refers to the load acting on a tire in its standard mounting condition. The aforementioned "standard mounting condition" refers to the tire being mounted on a standard vehicle corresponding to its intended use, and the tire being stationary on a flat road surface in a condition where the vehicle can drive.

[0040] The tread portion 2 has a plurality of circumferential grooves 3 extending continuously along the tire circumference between the first tread end T1 and the second tread end T2, and a plurality of land portions 4 divided by the circumferential grooves. The tire 1 of this embodiment is configured as a tire with a tread portion 2 including a so-called five-rib pattern of five land portions 4 divided by four circumferential grooves 3.

[0041] The circumferential groove 3 includes, 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 located between the first tread end T1 and the tire equator C. The second shoulder circumferential groove 8 is located between the second tread end T2 and the tire equator C. The first crown circumferential groove 6 is located between the first shoulder circumferential groove 5 and the tire equator C. The second crown circumferential groove 7 is located between the second shoulder circumferential groove 8 and the tire equator C.

[0042] The tire axial distance L1 from the tire equator C to the center line of the groove 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 tire axial distance L2 from the tire equator C to the center line of the groove 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. In addition, the tread width TW is the tire axial distance from the first tread end T1 to the second tread end T2 under the above-described normal state.

[0043] In this embodiment, each circumferential groove 3 extends in a straight line, parallel to the tire circumference. Each circumferential groove 3 may also extend in a wavy shape, for example.

[0044] The groove width W1 of each circumferential groove 3 is, for example, 2.0% to 10.0% of the tread width TW, more preferably 2.0% to 8.0%. In this embodiment, the first shoulder circumferential groove 5 has the smallest groove width among the four circumferential grooves 3. Furthermore, the first crown circumferential groove 6 has the second smallest groove width among the aforementioned four circumferential grooves 3. Therefore, rigidity can be improved on the first tread end T1 side of the tread portion 2, thereby uniformly improving braking performance, noise performance, and handling stability. However, the invention is not limited to this method. In the case of pneumatic tires for passenger cars, the depth of each circumferential groove 3 is preferably, for example, 5 to 10 mm.

[0045] More specifically, the width of the first shoulder circumferential groove 5 is preferably 2.9% to 4.0% of the tread width TW. Additionally, the width of the first crown circumferential groove 6 is, for example, 5.6% to 8.7% of the tread width TW, preferably 5.6% to 7.4%. The widths of the second shoulder circumferential groove 8 and the second crown circumferential groove 7 are, for example, 6.4% to 9.6%, preferably 7.7% to 9.6%.

[0046] The land portion 4 of the present invention includes: a first shoulder land portion 11, a first intermediate land portion 12, a crown land portion 13, a second intermediate land portion 14, and a second shoulder land portion 15. The first shoulder land portion 11 includes a first tread end T1. The second shoulder land portion 15 includes a second tread end T2.

[0047] The first intermediate land portion 12 is divided by the first shoulder circumferential groove 5 and the first crown circumferential groove 6, and is adjacent to the second tread end T2 side of the first shoulder land portion 11. The second intermediate land portion 14 is divided by the second shoulder circumferential groove 8 and the second crown circumferential groove 7, and is adjacent to the first tread end T1 side of the second shoulder land portion 15.

[0048] The crown land portion 13 is divided between the first crown circumferential groove 6 and the second crown circumferential groove 7. Thus, the crown land portion 13 is disposed between the first intermediate land portion 12 and the second intermediate land portion 14. In this embodiment, the crown land portion 13 is disposed on the tire equator C.

[0049] In this embodiment, each land portion 4 is provided with a cutting groove 16. In this specification, a "cutting groove" is a grooving element with a very small width, meaning that the width between the two groove walls in the main body of the cutting groove 16 is 1.5 mm or less. The width of the cutting groove 16 is preferably 0.2 to 1.2 mm, more preferably 0.5 to 1.0 mm. The cutting groove 16 may also include a widened portion with an opening wider than the aforementioned width, and a flask bottom with a width greater than the aforementioned width.

[0050] exist Figure 2 The image shows an enlarged view illustrating the shape of the contact patch when the tire tread 2 touches the ground. (See image for details.) Figure 2 As shown, when a standard inner pressure rim is assembled on a regular rim and 50% of the standard load is applied with the ground plane at a 0° camber angle, and the widths of the contact surfaces of the first shoulder land portion 11, the first intermediate land portion 12, the crown land portion 13, the second intermediate land portion 14, and the second shoulder land portion 15 are set to W1s, W1m, Wc, W2m, and W2s respectively, the following formula (1) is satisfied.

[0051] W1s>W1m>Wc>W2m≥W2s…(1)

[0052] By employing the above-described structure in this invention, ride comfort and noise performance can be improved. The following mechanism is presumed as the reason for this.

[0053] With the above-described structure, the tire 1 of the present invention can mitigate the rigidity of the land portion in the vehicle interior area of ​​the tread 2, thereby improving ride comfort. Furthermore, the impact sound of these land portions contacting the ground is also reduced, thus improving noise performance. Based on the above mechanism, it is presumed that the tire of the present invention can improve both ride comfort and noise performance.

[0054] Furthermore, for the tire 1 with the above-described structure, the land portion near the first tread end T1 has greater rigidity. Therefore, even when the center of the contact patch moves towards the first tread end T1 due to steering, the steering response remains stable, thereby generating a linear steering force in response to an increase in steering angle. Thus, the tire 1 of the present invention can exhibit superior handling stability.

[0055] The structure of this embodiment will be described in further detail below. Furthermore, each structure described below represents a specific embodiment. Therefore, it is self-evident that the present invention can achieve the above-described effects even without the structures described below. Furthermore, even when any one of the structures described below is applied individually to the tire of the present invention possessing the above-described features, an improvement in the performance corresponding to each structure can be expected. Additionally, when several of the structures described below are applied in combination, an improvement in the combined performance corresponding to each structure can be expected.

[0056] When a 50% load is applied, the tire axial width W1s of the contact surface of the first shoulder land portion 11 is preferably 115% to 125% of the tire axial width Wc of the contact surface of the crown land portion 13. This optimizes the rigidity of the first shoulder land portion 11, thereby improving noise performance along with the aforementioned effects.

[0057] According to the same view, under a 50% load condition, the tire axial width W1m of the contact surface of the first intermediate land portion 12 is preferably 101% to 107% of the tire axial width Wc of the contact surface of the crown land portion 13.

[0058] When a 50% load is applied, the tire axial width W2m of the contact patch of the second intermediate land portion 14 is preferably 90% to 99% of the tire axial width Wc of the contact patch of the crown land portion 13. This improves noise performance during straight-line driving. Furthermore, tire vibrations are less likely to be transmitted to the sides of the vehicle body during straight-line driving, thus improving ride comfort.

[0059] According to the same view, under a 50% load condition, the tire axial width W2s of the contact surface of the second shoulder land portion 15 is preferably 90% to 99% of the tire axial width Wc of the contact surface of the crown land portion 13.

[0060] As a further preferred embodiment, in this embodiment, under a 50% load condition, the width W2m of the second intermediate land portion 14 and the width W2s of the second shoulder land portion 15 are the same. This results in a more uniform wear progression between the second intermediate land portion 14 and the second shoulder land portion 15, thereby improving resistance to uneven wear.

[0061] exist Figure 3 The image shows an enlarged view of the first shoulder land portion 11 and the first intermediate land portion 12. (See image below.) Figure 3 As shown, only a sipe is provided on the first shoulder land portion 11. This improves the rigidity of the first shoulder land portion 11. In this embodiment, a plurality of first shoulder sipes 21 extending along the tire axial direction are provided on the first shoulder land portion 11.

[0062] A circumferential spacing length P1 of the first shoulder sipe 21 is, for example, 100% to 130% of the tread width W3 of the first shoulder land portion 11 in the tire axial direction. Furthermore, a circumferential spacing length of the two sipes is a distance parallel to the tire circumferential direction from the center position of the cross-section of one sipe to the aforementioned center position of the other sipe. Additionally, when the aforementioned distance varies along the tire axial direction, the intermediate distance corresponds to the aforementioned spacing length.

[0063] The first shoulder groove 21 is preferably in communication with at least the first shoulder circumferential groove 5. In this embodiment, the first shoulder groove 21 extends, for example, from the first shoulder circumferential groove 5 to the first tread end T1, completely traversing the tread of the first shoulder land portion 11. However, the first shoulder groove 21 is not limited to this manner and may also have an interrupted end within the first shoulder land portion 11.

[0064] The first shoulder groove 21 is inclined, for example, in a first direction (upper right in the figures of this specification) relative to the tire axial direction. The angle of the first shoulder groove 21 relative to the tire axial direction is, for example, 5 to 35°. In a further preferred embodiment, the first shoulder groove 21 includes a portion whose angle relative to the tire axial direction increases toward the second tread end T2. Such a first shoulder groove 21 can also exert friction in the tire axial direction.

[0065] The opening width W4 at the tread of the first shoulder sipe 21 is, for example, 4.0 to 8.0 mm. Such a first shoulder sipe 21 can improve resistance to uneven wear.

[0066] exist Figure 4 The diagram shown in the middle is a cross-section of the first shoulder groove 21. Figure 3 A sectional view along line AA. (e.g.) Figure 4 As shown, the first tire shoulder groove 21 includes a main body portion 21a extending radially along the tire, and a widened portion 21b with a tread opening on the land portion and a width greater than that of the main body portion 21a. In this embodiment, the width of the main body portion 21a is, for example, 0.5 to 1.5 mm.

[0067] The widened portion 21b of the first tire shoulder groove 21 includes an inclined surface 22 extending from the main body portion 21a toward the tread. In this embodiment, the inclined surface 22 is planar and inclined at an angle θ1 of 50 to 70° relative to the tire radial direction. This widened portion 21b allows the entire surface of the inclined surface 22 to make contact with the ground when a large ground pressure is applied to the land portion, thus reliably increasing the actual contact area of ​​the tread. This improves handling stability and ride comfort.

[0068] The depth d1 of the widened portion 21b of the first shoulder groove 21 is 10% to 30% of the maximum depth d3 of the first shoulder groove 21, and preferably 0.5 to 2.0 mm. Alternatively, the maximum depth d3 of the first shoulder groove 21 is, for example, 70% to 100% of the depth of the circumferential groove 3.

[0069] The width W6 (width along the tread surface in the cross-section of the groove) of the widened portion 21b of the first shoulder groove 21 is, for example, 2.0 to 4.0 mm.

[0070] exist Figure 5 The middle shows Figure 3 A CC-line sectional view. For example... Figure 5As shown, the first shoulder groove 21 includes a shallow bottom 23 formed by a partial bulge at the bottom. In this embodiment, the shallow bottom 23 is, for example, provided in a connecting portion that communicates with the first shoulder circumferential groove 5. The minimum depth d4 of the shallow bottom 23 of the first shoulder groove 21 is 40% to 60% of the maximum depth d3 of the first shoulder groove 21. The tire axial length L3 of the shallow bottom 23 is equal to the tire axial width W3 of the first shoulder land portion 11. Figure 3 (As shown) 10% to 30%. Furthermore, the aforementioned length L3 of the shallow bottom 23 is measured, for example, at the center position in the height direction of the shallow bottom 23. The first shoulder groove 21 having such a shallow bottom 23 maintains the rigidity of the first shoulder land portion 11, thereby improving handling stability.

[0071] like Figure 3 As shown, the first intermediate land portion 12 includes: a first longitudinal edge 12a on the side of the first tread end T1, a second longitudinal edge 12b on the side of the second tread end T2, and a tread surface between the first longitudinal edge 12a and the second longitudinal edge 12b. Furthermore, the first intermediate land portion 12 is only provided with sipes. This improves the rigidity of the first intermediate land portion 12. In this embodiment, the first intermediate land portion 12 is provided with a plurality of first intermediate sipes 30 extending along the tire axial direction. The opening width W5 of the first intermediate sipe 30 at the tread surface is, for example, smaller than the opening width W4 of the first shoulder sipe 21 at the tread surface. Specifically, the opening width W5 of the first intermediate sipe 30 is, for example, 2.0 to 6.0 mm. Furthermore, the opening width W5 of the first intermediate sipe 30 is 50% to 90% of the opening width W4 of the first shoulder sipe 21. Such a first intermediate sipe 30 can improve resistance to uneven wear.

[0072] exist Figure 6 The diagram shown is a cross-section of the first intermediate tool groove 30. Figure 3 A BB-line sectional view. For example... Figure 6 As shown, the first intermediate groove 30 includes a main body portion 30a extending radially along the tire, and a widened portion 30b with a tread opening on the land portion and a width greater than that of the main body portion 30a. In this embodiment, the width of the main body portion 30a is, for example, 0.5 to 1.5 mm.

[0073] The widened portion 30b of the first intermediate groove 30 includes an inclined surface 25 extending from the main body portion 30a toward the tread surface. In this embodiment, the inclined surface 25 is planar and inclined at an angle θ2 of 30 to 60° relative to the radial direction of the tire.

[0074] The depth d2 of the widened portion 30b of the first intermediate sipe 30 is 15% to 30% of the maximum depth d5 ​​of the first intermediate sipe 30. Furthermore, the depth d2 of the widened portion 30b of the first intermediate sipe 30 is, for example, 1.0 to 3.0 mm. In a more preferred embodiment, the depth d1 of the widened portion 21b of the first shoulder sipe 21 is... Figure 4 (As shown) The depth d2 of the widened portion 30b of the first intermediate sipe 30 is less than that of the first shoulder 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 intermediate sipe 30, preferably 60% to 80%.

[0075] The width W8 (width along the tread surface in the cross-section of the cutter groove) of the inclined surface 25 of the widened portion 30b of the first intermediate cutter groove 30 is, for example, 1.0 to 3.0 mm.

[0076] like Figure 3 As shown, the first intermediate cutting groove 30 includes: an outer first intermediate cutting groove 31 extending from the first longitudinal edge 12a and having an interrupted end 31a in the first intermediate land portion 12, and an inner first intermediate cutting groove 32 extending from the second longitudinal edge 12b and having an interrupted end 32a in the first intermediate land portion 12.

[0077] When viewed from above, the first intermediate sipe 30 extends in a straight line. Furthermore, the first intermediate sipe 30 is inclined in a first direction relative to the tire axial direction. More specifically, when viewed from above, the outer first intermediate sipe 31 and the inner first intermediate sipe 32 extend in a straight line and are inclined in a first direction relative to the tire axial direction.

[0078] The angle of the outer first intermediate sipe 31 relative to the tire axial direction and the angle of the inner first intermediate sipe 32 relative to the tire axial direction are preferably 20° or more, more preferably 25° or more, and even more preferably 45° or less, more preferably 40° or less. Such outer first intermediate sipe 31 and inner first intermediate sipe 32 provide frictional force evenly in the tire axial and circumferential directions.

[0079] The angle difference between the outer first intermediate groove 31 and the inner first intermediate groove 32 is preferably 10° or less, more preferably 5° or less, and in this embodiment they are arranged in parallel. Such an outer first intermediate groove 31 and inner first intermediate groove 32 can suppress uneven wear of the first intermediate land portion 12.

[0080] The outer first intermediate sipe 31 and the inner first intermediate sipe 32 do not traverse the center position of the tire axial direction of the first intermediate land portion 12, but are interrupted instead. The tire axial length La of the outer first intermediate sipe 31 is 20% or more, more preferably 25% or more, and more preferably 45% or less, and more preferably 40% or less, of the tire axial width W7 of the first intermediate land portion 12. Similarly, the tire axial length Lc of the inner first intermediate sipe 32 is 20% or more, more preferably 25% or more, and more preferably 45% or less, and more preferably 40% or less, of the tire axial width W7 of the first intermediate land portion 12. Such outer first intermediate sipe 31 and inner first intermediate sipe 32 can maintain handling stability and improve ride comfort and noise performance.

[0081] The outer first intermediate sipe 31 and the inner first intermediate sipe 32 are preferably offset along the tire circumference. Therefore, in this embodiment, when viewed from above, the imaginary region formed by extending the outer first intermediate sipe 31 parallel to the tire axial direction does not overlap with the inner first intermediate sipe 32. Furthermore, the interrupted ends 31a of the outer first intermediate sipe 31 and 32a of the inner first intermediate sipe 32 are offset along the tire circumference. The tire circumference distance Lb between the interrupted ends 31a of the outer first intermediate sipe 31 and 32a of the inner first intermediate sipe 32 is, for example, less than 50% of the tire circumference spacing length P2 of the first intermediate sipe 30, preferably 25% to 40%. In a further preferred embodiment, the distance Lb is within the range of the following formula (2). Therefore, the spacing of each sipe is easily converted into white noise, thereby improving noise performance.

[0082] Lb=2La±1(mm)…(2)

[0083] In addition, the spacing length P2 of the first intermediate sipe 30 is, for example, 80% to 120% of the spacing length P1 of the first shoulder sipe 21, and in a more preferred embodiment they are the same.

[0084] In this embodiment, the outer first intermediate sipe 31 communicates with the first shoulder circumferential groove 5. Furthermore, when viewed from above, the widened portion of the outer first intermediate sipe 31 overlaps with the area obtained by extending the widened portion 21b of the first shoulder sipe 21 along its length. Thus, the outer first intermediate sipe 31 and the first shoulder sipe 21 work together to further improve wet road performance.

[0085] The first intermediate cutting groove 30 has a constant depth along its length. More specifically, the outer first intermediate cutting groove 31 and the inner first intermediate cutting groove 32 each have a constant depth along their length. The depth of the inner first intermediate cutting groove 32 is, for example, 70% to 100% of the depth of the circumferential groove 3. Furthermore, the maximum depth of the outer first intermediate cutting groove 31 is less than the maximum depth of the inner first intermediate cutting groove 32. The maximum depth of the outer first intermediate cutting groove 31 is 30% to 70% of the maximum depth of the inner first intermediate cutting groove 32, and preferably 1.0 to 2.5 mm.

[0086] In addition, the outer first intermediate tool groove 31 and the inner first intermediate tool groove 32 can be applied respectively. Figure 6 The cross-sectional shape of the cutter groove is shown. Such an outer first intermediate cutter groove 31 and an inner first intermediate cutter groove 32 whiten the spacing of each cutter groove, thereby improving noise performance and improving ride comfort and handling stability in a balanced way.

[0087] like Figure 3 As shown, a first longitudinal groove 33 extending circumferentially along the tire is provided in the first intermediate land portion 12, for example. In this embodiment, the first longitudinal groove 33 extends continuously circumferentially along the tire. When driving on wet roads, such a first longitudinal groove 33 provides axial friction for the tire. Another embodiment of the first longitudinal groove 33 will be described later.

[0088] The first longitudinal groove 33 is provided, for example, in the region at the center of the first intermediate land portion 12 when it is divided into three equal parts along the tire axial direction. The distance along the tire axial direction from the first longitudinal groove 33 to the center position of the first intermediate land portion 12 is preferably less than 10% of the width W7 of the first intermediate land portion 12 along the tire axial direction, more preferably less than 5%. Such an arrangement of the first longitudinal groove 33 can suppress uneven wear of the first intermediate land portion 12.

[0089] exist Figure 7 The middle shows Figure 2 A DD-line sectional view. For example... Figure 7 As shown, the first longitudinal groove 33 is formed with a constant width, for example, from the opening end toward the bottom.

[0090] exist Figure 8 The diagram shows an enlarged view of the first intermediate landmass 12, the crown landmass 13, and the second intermediate landmass 14. Figure 8As shown, the land portion 13 of the tire crown includes: a first longitudinal edge 13a on the side of the first tread end T1, a second longitudinal edge 13b on the side of the second tread end T2, and a tread surface between the first longitudinal edge 13a and the second longitudinal edge 13b. Similarly, the second intermediate land portion 14 includes: a first longitudinal edge 14a on the side of the first tread end T1, a second longitudinal edge 14b on the side of the second tread end T2, and a tread surface between the first longitudinal edge 14a and the second longitudinal edge 14b.

[0091] The tread land portion 13 includes an outer contact surface 36 on the side closer to the first tread end T1 than the tire equator C and an inner contact surface 37 on the side closer to the second tread end T2 than the tire equator C. In this embodiment, when the axial widths of the outer contact surface 36 and the inner contact surface 37 are set to Wco and Wci respectively, the following formula (3) is satisfied. Such a tread land portion 13 helps to improve handling stability.

[0092] Wco>Wci…(3)

[0093] The axial width Wco of the outer contact surface 36 is, for example, 51% to 60% of the axial width W9 of the contact surface of the crown land portion 13, preferably 51% to 55%. This suppresses uneven wear of the crown land portion 13 and improves handling stability.

[0094] Only a sipes are provided in the land portion 13 of the tire crown. This improves the rigidity of the land portion 13 of the tire crown.

[0095] The land portion 13 of the tire crown is provided with a plurality of crown grooves 40 that are inclined in a second direction (to the lower right in the figures of this specification) relative to the tire axial direction and opposite to the first direction. In this embodiment, the crown grooves 40 are inclined in the second direction and extend in a straight line. Such crown grooves 40, together with the first intermediate groove 30, work together to provide friction in multiple directions, thereby improving wet road performance.

[0096] The tire crown sipe 40 has a tire circumferential spacing length P3, for example, the tire circumferential spacing length P2 of the first intermediate sipe 30. Figure 3 The percentages (shown) are 80% to 120%, and in this embodiment they are the same. This configuration of the grooves improves resistance to uneven wear.

[0097] The angle of the tread groove 40 relative to the tire axial direction is preferably 20° or more, more preferably 25° or more, and even more preferably 45° or less, more preferably 40° or less. The tread groove 40 provides friction evenly in both the tire circumferential and axial directions.

[0098] The crown groove 40 includes: an outer crown groove 41 extending from the first longitudinal edge 40a and having an interrupted end 41a within the crown land portion 13, and an inner crown groove 42 extending from the second longitudinal edge 40b and having an interrupted end 42a within the crown land portion 13.

[0099] The angle difference between the outer crown sipe 41 and the inner crown sipe 42 is preferably 10° or less, more preferably 5° or less, and in this embodiment, they are arranged in parallel. Such outer crown sipe 41 and inner crown sipe 42 suppress uneven wear of the crown land portion 13.

[0100] The outer crown sipe 41 and the inner crown sipe 42 do not traverse the center of the tire axial direction of the crown land portion 13, but are interrupted instead. The tire axial length L4 of the outer crown sipe 41 and the tire axial length L5 of the inner crown sipe 42 are, for example, 20% to 35% of the tire axial width W9 of the crown land portion 13. Such outer crown sipes 41 and inner crown sipes 42 improve handling stability and ride comfort in a balanced way.

[0101] The outer sipe 41 and the inner sipe 42 are preferably offset along the tire circumference. Therefore, in this embodiment, when viewed from above, the imaginary region formed by extending the outer sipe 41 parallel to the tire axial direction does not overlap with the inner sipe 42. Furthermore, the interrupted ends 41a of the outer sipe 41 and 42a of the inner sipe 42 are offset along the tire circumference. The tire circumferential distance L6 between the interrupted ends 41a of the outer sipe 41 and 42a of the inner sipe 42 is preferably, for example, less than the tire circumferential distance Lb between the interrupted ends 31a of the outer first intermediate sipe 31 and 32a of the inner first intermediate sipe 32. Specifically, the distance L6 is preferably 70% or less of the distance Lb, more preferably 60% or less, and even more preferably 30% or more, more preferably 40% or more. This sipe arrangement whitens the spacing between the sipes, thereby improving noise performance.

[0102] The outer crown sipe 41 and the inner crown sipe 42 each have a constant depth along their length. The depth of the inner crown sipe 42 is, for example, 70% to 100% of the depth of the circumferential groove 3. Furthermore, the maximum depth of the outer crown sipe 41 is less than the maximum depth of the inner crown sipe 42. The maximum depth of the outer crown sipe 41 is 30% to 70% of the maximum depth of the inner crown sipe 42, and preferably 1.0 to 2.5 mm.

[0103] The outer crown groove 41 and the inner crown groove 42 can be applied to... Figure 6 The cross-sectional shape of the first intermediate cutter groove 30 is described in the diagram. Therefore, the description is omitted here.

[0104] The second intermediate land section 14 is provided with only a cutter groove. This improves the rigidity of the second intermediate land section 14.

[0105] The second intermediate land portion 14 is provided with a plurality of second intermediate grooves 45 that are inclined in the second direction relative to the tire axis. In this embodiment, the second intermediate grooves 45 are inclined in the second direction and extend in a straight line.

[0106] The tire circumferential spacing length P4 of the second intermediate sipe 45 is, for example, 80% to 120% of the tire circumferential spacing length P3 of the crown sipe 40; in this embodiment, they are the same. Such a sipe configuration improves resistance to uneven wear.

[0107] The angle of the second intermediate groove 45 relative to the tire axial direction is preferably 20° or more, more preferably 25° or more, more preferably 45° or less, and more preferably 40° or less. Such a second intermediate groove 45 provides friction evenly in both the tire circumferential and axial directions.

[0108] The second intermediate groove 45 includes: an outer second intermediate groove 46 extending from the first longitudinal edge 14a and having an interrupted end 46a in the crown land portion 13, and an inner second intermediate groove 47 extending from the second longitudinal edge 14b and having an interrupted end 47a in the crown land portion 13.

[0109] The angle difference between the outer second intermediate cutting groove 46 and the inner second intermediate cutting groove 47 is preferably 10° or less, more preferably 5° or less, and in this embodiment they are arranged in parallel. Such outer second intermediate cutting groove 46 and inner second intermediate cutting groove 47 suppress uneven wear of the second intermediate land portion 14.

[0110] The outer second intermediate sipe 46 and the inner second intermediate sipe 47 do not traverse the center of the tire axial direction of the second intermediate land portion 14 but are interrupted. The tire axial length L7 of the outer second intermediate sipe 46 and the tire axial length L8 of the inner second intermediate sipe 47 are, for example, greater than the aforementioned length L4 of the outer crown sipe 41 and the aforementioned length L5 of the inner crown sipe 42. Specifically, the aforementioned length L7 of the outer second intermediate sipe 46 and the aforementioned length L8 of the inner second intermediate sipe 47 are 25% to 35% of the tire axial width W10 of the second intermediate land portion 14. Such outer second intermediate sipes 46 and inner second intermediate sipes 47 help improve wet road performance and ride comfort.

[0111] The outer second intermediate sipe 46 and the inner second intermediate sipe 47 are preferably offset along the tire circumferential direction. Therefore, in this embodiment, when viewed from above, the overlapping area of ​​the imaginary region obtained by extending the outer second intermediate sipe 46 parallel to the tire axial direction and the inner second intermediate sipe 47 is less than 10% of the opening area of ​​the inner second intermediate sipe 47. Furthermore, the interrupted ends 46a of the outer second intermediate sipe 46 and 47a of the inner second intermediate sipe 47 are offset along the tire circumferential direction. The tire circumferential distance L9 between the interrupted ends 46a of the outer second intermediate sipe 46 and 47a of the inner second intermediate sipe 47 is, for example, less than the tire circumferential distance Lb between the interrupted ends 31a of the outer first intermediate sipe 31 and 32a of the inner first intermediate sipe 32, and preferably less than the tire circumferential distance L6 between the interrupted ends 41a of the outer crown sipe 41 and 42a of the inner crown sipe 42. Specifically, the aforementioned distance L9 is preferably 80% or less of the aforementioned distance L6, more preferably 70% or less, and even more preferably 40% or more, more preferably 50% or more. This arrangement of the sipes optimizes the rigidity balance of each land section, thereby improving both handling stability and ride comfort in a balanced manner.

[0112] The outer second intermediate sipe 46 and the inner second intermediate sipe 47 each have a constant depth along their length. The depth of the inner second intermediate sipe 47 is, for example, 70% to 100% of the depth of the circumferential groove 3. Furthermore, the maximum depth of the outer second intermediate sipe 46 is less than the maximum depth of the inner second intermediate sipe 47. The maximum depth of the outer second intermediate sipe 46 is 30% to 70% of the maximum depth of the inner second intermediate sipe 47, preferably 1.0 to 2.5 mm. Such outer crown sipes 41 and inner crown sipes 42 reduce the spacing between the sipes, thus improving noise performance and providing a balanced improvement in ride comfort and handling stability.

[0113] The outer second intermediate groove 46 and the inner second intermediate groove 47 can be applied to... Figure 6 The cross-sectional shape of the first intermediate cutter groove 30 is described in the diagram. Therefore, the description is omitted here.

[0114] For example, a second longitudinal groove 48 extending circumferentially along the tire is provided in the second intermediate land portion 14. In this embodiment, the second longitudinal groove 48 extends continuously along the tire circumferential direction. In addition, the second longitudinal groove 48 has the same cross-sectional shape as the first longitudinal groove 33 described above. Such a second longitudinal groove 48 provides axial friction force for the tire.

[0115] The second longitudinal groove 48 is provided, for example, in the region at the center of the second intermediate land portion 14 when it is divided into three equal parts along the tire axial direction. The distance along the tire axial direction from the second longitudinal groove 48 to the center position of the second intermediate land portion 14 is preferably less than 10% of the width W10 of the second intermediate land portion 14 along the tire axial direction, and more preferably less than 5%.

[0116] exist Figure 9 The middle shows Figure 1 Enlarged view of the second shoulder land portion 15. (See image below.) Figure 9 As shown, only a sipe is provided on the second shoulder land portion 15. This improves the rigidity of the second intermediate land portion 14.

[0117] For example, a plurality of second shoulder grooves 50 extending along the tire axial direction are provided on the second shoulder land portion 15. In this embodiment, the total number of second shoulder grooves 50 is greater than the number of first shoulder grooves 21 (e.g., Figure 3 The total number of slots shown below (and the same applies below) is calculated. This configuration of the cutter grooves improves noise performance and wet-road performance.

[0118] To maintain handling stability and improve noise and wet road performance, the total number of second shoulder grooves 50 is preferably the same as the number of first shoulder grooves 21 (e.g., ...). Figure 3 The total number of items (as shown) is more than 1.3 times, more preferably more than 1.5 times, even more preferably more than 1.8 times, and preferably less than 2.8 times, more preferably less than 2.5 times, and even more preferably less than 2.2 times.

[0119] The tire shoulder sipe 50 has a tire circumferential spacing length P5, for example, the tire circumferential spacing length P4 of the second intermediate sipe 45 (e.g. Figure 8 (shown) 30% to 70%.

[0120] The second shoulder sipe 50 is inclined, for example, in the first direction. That is, the first shoulder sipe 21 (as shown) Figure 3 As shown (and the same applies below), the second shoulder groove 50 is inclined in the same direction relative to the tire axis. In this embodiment, the second shoulder groove 50 is inclined in the first direction and extends in a straight line.

[0121] The angle of the second shoulder sipe 50 relative to the tire axial direction is, for example, 20° or less, preferably 15° or less, and more preferably 10° or less. Therefore, in this embodiment, the maximum angle of the first shoulder sipe 21 relative to the tire axial direction is greater than the maximum angle of the second shoulder sipe 50 relative to the tire axial direction. This sipe configuration further improves noise performance.

[0122] The second shoulder groove 50 can be applied to Figure 4The cross-sectional shape of the first shoulder groove 21 is described in the diagram. Therefore, the description is omitted here.

[0123] The second shoulder groove 50 includes, for example, a transverse second shoulder groove 51 that completely traverses the second shoulder land portion 15 along the tire axial direction, and an interrupted second shoulder groove 52 that extends at least from the second tread end T2 toward the tire axial direction and has an interrupted end within the second shoulder land portion 15.

[0124] The axial length of the tire that interrupts the second shoulder sipe 52 is greater than that of the first intermediate sipe 30 (e.g.) Figure 3 (as shown), crown groove 40 and second intermediate groove 45 (as shown) Figure 8 The tire axial length of any one of the tires shown. The tire axial length L10 of the second shoulder groove 50 is preferably 50% or more, more preferably 60% or more, and even more preferably 90% or less, and more preferably 80% or less, of the tire axial width W11 of the second shoulder land portion 15. Such interruption of the second shoulder groove 52 improves ride comfort and handling stability in a balanced way.

[0125] exist Figure 10 The middle shows Figure 9 A sectional view along the EE line. (e.g.) Figure 10 As shown, the second shoulder groove 51 includes a shallow bottom 53 formed by a partial bulge at the bottom. In this embodiment, the shallow bottom 53 is, for example, provided in a connecting portion that communicates with the second shoulder circumferential groove 8. The shallow bottom 23 of the first shoulder groove 21 (e.g., ...) can be applied to the shallow bottom 53 of the second shoulder groove 50. Figure 5 The structure shown is omitted here. The transverse second shoulder sipe 51, including such a shallow bottom 53, can maintain the rigidity of the second shoulder land portion 15, thereby improving handling stability.

[0126] like Figure 1 As shown, in this embodiment, only a cutter groove 16 is provided in each of the five land sections 4, and no drainage channel is provided. This maintains the rigidity of each land section and prevents pumping noise from the drainage channel, thus improving noise performance.

[0127] Hereinafter, other embodiments of the present invention will be described. In the figures illustrating other embodiments, the elements already described are labeled with the same reference numerals as those described above, and the above-described structure can be applied.

[0128] exist Figure 11 An enlarged view of the first intermediate land section 12 in another embodiment is shown. (See diagram below.) Figure 11As shown, the first longitudinal sipe 33 provided in the first intermediate land portion 12 extends in a serrated shape along the tire circumference. The first longitudinal sipe 33 extends in a wavy shape, for example, with a smooth curve. The axial sway A1 (value between peaks) of the first longitudinal sipe 33 is, for example, 1.0% to 8.0% of the axial width W7 of the first intermediate land portion 12. Furthermore, the first longitudinal sipe 33 extends in a serrated shape with a period of two intervals relative to the first intermediate sipe 30. Such a first longitudinal sipe 33 can also provide friction in the tire circumference.

[0129] exist Figure 12 The image shows an enlarged view of the first intermediate land section 12 in yet another embodiment. (See image for details.) Figure 12 As shown, the first longitudinal sipe 33 provided in the first intermediate land portion 12 extends discontinuously along the tire circumference. That is, the first longitudinal sipe 33 is composed of a plurality of longitudinal sipes 54 arranged side by side along the tire circumference. The tire circumferential length L11 of one longitudinal sipe 54 is, for example, 20% to 60% of the tire circumferential spacing length P2 of the first intermediate sipe 30. Such a first longitudinal sipe 33 can maintain the rigidity of the first intermediate land portion 12 and provide axial friction force for the tire.

[0130] Figure 11 as well as Figure 12 The structure of the first longitudinal cutter groove 33 shown can also be applied to the second longitudinal cutter groove 48 provided in the second intermediate land portion 14.

[0131] exist Figure 13 as well as Figure 14 The diagram shows an enlarged view of a first shoulder land portion 11 and a second shoulder land portion 15, representing yet another embodiment. Figure 13 The first shoulder land portion 11 of the illustrated embodiment is provided with a plurality of first shoulder sipes 21 extending in a wavy shape. When viewed from above, these first shoulder sipes 21 are wavy, extending along both the tire's circumferential axis and axial direction. Such first shoulder sipes 21 increase the rigidity of the land portion when the two sipe walls contact each other, thereby improving handling stability. Furthermore, compared to straight sipes, these first shoulder sipes 21 can mitigate the impact on the edges during contact, thereby suppressing contact noise.

[0132] In this embodiment, the first shoulder groove 21 extends, for example, from the first shoulder periphery to the groove 5 and then to the first tread end T1. Furthermore, the center of the swing of the first shoulder groove 21 is inclined at an angle of less than 30° relative to the tire axial direction. Such a first shoulder groove 21 helps to improve both ride comfort and handling stability in a balanced manner.

[0133] To further enhance the aforementioned effects, the second shoulder land portion 15 in this embodiment is provided with a plurality of second shoulder grooves 50 that extend in a wavy shape when viewed from above. The second shoulder grooves 50 are wavy, extending along the tire circumferential swing on one side and along the tire axial direction on the other.

[0134] As a further preferred embodiment, the second shoulder groove 50 includes: a transverse second shoulder groove 51 extending from the second shoulder circumferential groove 8 to the second tread end T2, and an interrupted second shoulder groove 52 extending from the second tread end T2 and interrupted within the second shoulder land portion 15. Furthermore, the transverse second shoulder groove 51 and the interrupted second shoulder groove 52 are alternately arranged along the tire circumferential direction. This maintains handling stability and improves noise performance.

[0135] exist Figure 14 The first shoulder land portion 11 of the illustrated embodiment is provided with a pair of first sipes 56, which are formed by two first shoulder sipes 21 extending in a wavy manner and spaced axially by a distance L12 of 6-12 mm side by side. The first sipe pair 56 is, for example, composed of closed sipes 61 interrupted at both ends within the first shoulder land portion 11 and semi-open sipes 62 extending from the circumferential groove 5 of the first shoulder and interrupted within the first shoulder land portion 11. Furthermore, multiple such pairs of first sipes 56 are provided along the tire circumference. The first shoulder land portion 11 with such a pair of first sipes 56 can provide superior handling stability and improve noise performance and ride comfort.

[0136] To further enhance the aforementioned effect, a second pair of sipes 57 is provided on the second shoulder land portion 15. This pair of sipes 57 is formed by two second shoulder sipes 50 extending in a wavy pattern, spaced 6-12 mm apart axially in the tire. The second pair of sipes 57 may include, for example, closed sipes 63 that are interrupted at both ends within the second shoulder land portion 15, and semi-open sipes 64 that extend from the circumference of the second shoulder towards the groove 8 and are also interrupted within the second shoulder land portion 15. Alternatively, the second pair of sipes 57 may also include the aforementioned closed sipes 63 and at least a tread end-side sipe 65 extending axially inward from the second tread end T2.

[0137] like Figure 13 As shown, the first shoulder sipe 21 and the second shoulder sipe 50, which extend in a wavy shape, extend in a triangular wavy shape, for example, bending at an angle θ3 of 90 to 130°. Furthermore, the swivel amplitude of this sipe is, for example, 1.0 to 1.6 mm.

[0138] The wavy grooves are not limited to the above-described manner. For example, multiple wavy grooves with a radius of 0.6 to 1.4 mm can be connected along the tire axial direction. In addition, besides this method, various waveforms such as sine waves, rectangular waves, and trapezoidal waves can also be used for the wavy grooves.

[0139] The aforementioned wavy-extending shoulder sipes are a more preferred embodiment, and can also be configured as so-called 3D sipes extending wavyly in both the length and depth directions. This further enhances the aforementioned effects. Furthermore, when such shoulder sipes are provided, it is preferable that the two walls of each intermediate sipe are planar.

[0140] in addition, Figure 13 as well as Figure 14 The wavy groove shown does not include the widened portion mentioned above, but extends from the ground contact surface of the land portion to the bottom of the groove with a constant width. As a result, the edge of the groove can generate greater friction.

[0141] Hereinafter, another embodiment of the present invention will be described. In the figures illustrating the embodiments described below, the elements already described are labeled with the same reference numerals as those described above, thereby enabling the application of the above-described structure.

[0142] Figure 15 An unfolded view of the tread portion 2 of another embodiment is shown. Figure 16 Show Figure 15 Enlarged views of the first intermediate landmass 12, the crown landmass 13, and the second intermediate landmass 14 of the illustrated embodiment. Figure 15 as well as Figure 16 As shown, in this embodiment, the main difference is that the cutting grooves provided on each land portion are changed from those in the embodiment described above. Furthermore, even in this embodiment, the structure already described can be applied regarding the width of each land portion.

[0143] like Figure 16 As shown, in this embodiment, the sipes provided in the first intermediate land portion 12, the crown land portion 13, and the second intermediate land portion 14 are inclined in the same direction relative to the tire axis, specifically, inclined in the first direction (left lower, right higher) relative to the tire axis. The angle of each sipe relative to the tire axis is, for example, 10 to 30°. This arrangement of sipes makes the deformation of each land portion uniform upon contact with the ground, thereby making the ground pressure acting on each land portion uniform. As a result, the land portions work together to exert greater grip.

[0144] In a preferred embodiment, in the first intermediate land portion 12, the crown land portion 13, and the second intermediate land portion 14, two sipes adjacent along the tire axial direction are preferably arranged to be offset along the tire circumferential direction. Furthermore, two sipes adjacent along the tire axial direction (i.e., a pair formed by the inner first intermediate sipe 32 and the outer crown sipe 41, or a pair formed by the outer second intermediate sipe 46 and the inner crown sipe 42) separated by the first crown circumferential groove 6 or the second crown circumferential groove 7 are also preferably arranged to be offset along the tire circumferential direction. Specifically, when viewed from above, the two sipes are preferably arranged such that the imaginary area obtained by extending one of the two sipes parallel to the tire axial direction and the overlapping area of ​​the other sipe are less than 10% of the opening area of ​​the other sipe. This reduces the overlap of the spacing between the two sipes, thereby improving noise performance.

[0145] like Figure 15 As shown, in this embodiment, when viewed from above, the outer first intermediate sipe 31 and inner first intermediate sipe 32 provided on the first intermediate land portion 12, the outer crown sipe 41 and inner crown sipe 42 provided on the crown land portion 13, and the outer second intermediate sipe 46 and inner second intermediate sipe 47 provided on the second intermediate land portion 14 are arranged in an imaginary band 70 extending with a very small width (in Figure 15 The imaginary band 70 is an imaginary area that extends at an angle with a constant width in the same direction as each cutter groove. In a preferred embodiment, each cutter groove is configured such that the imaginary band 70 has a width of 30 mm or less, and more preferably 20 mm or less. As a result, grip performance and noise performance are further improved.

[0146] like Figure 16As shown, in this embodiment, the tire circumferential distances L14 between the interrupted end 31a of the outer first intermediate sipe 31 and the interrupted end 32a of the inner first intermediate sipe 32, L15 between the interrupted end 41a of the outer crown sipe 41 and the interrupted end 42a of the inner crown sipe 42, and L16 between the interrupted end 46a of the outer second intermediate sipe 46 and the interrupted end 47a of the inner second intermediate sipe 47 are preferably appropriately defined. Similarly, the tire circumferential distances L17 between the end 32b of the inner first intermediate sipe 32 on the first crown circumferential groove 6 side and the end 41b of the outer crown sipe 41 on the first crown circumferential groove 6 side, and L18 between the end 46b of the outer second intermediate sipe 46 on the second crown circumferential groove 7 side and the end 42b of the inner crown sipe 42 on the second crown circumferential groove 7 side, are preferably appropriately defined. This is because if these distances are large, the ground pressure acting on each land surface is likely to become uneven, thus raising concerns about reduced grip performance. If these distances are small, the spacing between each slot is likely to be repetitive, thus raising concerns about reduced noise performance.

[0147] Based on this viewpoint, the aforementioned distance L14 is preferably 30% or more, more preferably 50% or more, more preferably 200% or less, and more preferably 150% or less, of the maximum tire circumferential length L19 of the outer first intermediate sipe 31 or the inner first intermediate sipe 32. Similarly, the aforementioned distance L16 is preferably 30% or more, more preferably 50% or more, more preferably 200% or less, and more preferably 150% or less, of the maximum tire circumferential length L20 of the outer second intermediate sipe 46 or the inner second intermediate sipe 47. This results in a balanced improvement in both noise performance and grip performance.

[0148] The aforementioned distance L15 is preferably 100% or more, more preferably 150% or more, more preferably 300% or less, and more preferably 250% or less, of the maximum tire circumferential length L21 of the outer tread sipe 41 or the inner tread sipe 42. On the other hand, since a large ground pressure acts on the tread land portion 13, the arrangement of the sipes disposed on the tread land portion 13 has a significant impact on various performance characteristics, and is therefore preferably specified more precisely. Thus, in a further preferred embodiment, the aforementioned distance L15 falls within the range of 200% ± 1.0 mm of the aforementioned length L21.

[0149] The aforementioned distance L17 is preferably 10% or more, more preferably 30% or more, more preferably 150% or less, and more preferably 100% or less, of the maximum tire circumferential length L22 of the inner first intermediate sipe 32 or the outer crown sipe 41. On the other hand, the aforementioned distance L18 is preferably 50% or more, more preferably 100% or more, of the maximum tire circumferential length L20 of the outer second intermediate sipe 46 or the inner crown sipe 42, and more preferably 200% or less, of the maximum tire circumferential length L20.

[0150] In this embodiment, the outer first intermediate cutting groove 31, the inner first intermediate cutting groove 32, the outer second intermediate cutting groove 46, and the inner second intermediate cutting groove 47, in the cross-section of the cutting groove, have the same characteristics as... Figure 6 The structure shown is the same as the one described above. That is, as... Figure 6 As shown, these sipes include a main body extending radially along the tire and a tread opening on the land portion, having a widened portion that is wider than the main body. Additionally, the widened portion includes an inclined surface extending from the main body to the tread. They are capable of employing the aforementioned structure.

[0151] like Figure 16 As shown, the outer first intermediate sipe 31, the inner first intermediate sipe 32, the outer second intermediate sipe 46, and the inner second intermediate sipe 47 are provided with inclined surfaces on both sides of the sipe. Furthermore, each inclined surface is uniformly distributed along the length of the sipe. Additionally, the width of each inclined surface increases towards the inner or outer side of the tire axial direction. Preferably, the width of each inclined surface varies continuously along the tire axial direction. However, this is not a limitation; the inclined surface may be provided only in a portion of the sipe, or it may extend with a constant width.

[0152] Figure 17 Show Figure 16 Enlarged view of the outer first intermediate cutting groove 31 and the inner first intermediate cutting groove 32. (See attached image.) Figure 17 As shown, in the inclined surface 31s of the outer first intermediate sipe 31, the width W12 at the end of the first longitudinal edge 12a side is preferably greater than the width W13 at the end of the second longitudinal edge 12b side. The width W12 of the inclined surface 31s is, for example, 1.5 to 4.0 times the width W13. Furthermore, in the inclined surface 32s of the inner first intermediate sipe 32, the width W14 at the end of the second longitudinal edge 12b side is greater than the width W15 at the end of the first longitudinal edge 12a side. The width W14 of the inclined surface 32s is, for example, 2.5 to 5.0 times the width W15. This allows the inclined surface of each sipe to be grounded as a whole, and enables a uniform ground pressure to be applied to the entire inclined surface. Therefore, superior grip performance can be achieved. Furthermore, the widths of the inclined surfaces mentioned above refer to the width of the inclined surface along the tread surface of the land portion in a cross-section orthogonal to the length direction of the sipe.

[0153] The width W12 of the inclined surface 31s of the outer first intermediate knife groove 31 is preferably smaller than the width W14 of the inclined surface 32s of the inner first intermediate knife groove 32. Specifically, the width W12 is 40% to 60% of the width W14. As a result, a larger inclined surface is formed on the side of the second longitudinal edge 12b where the grounding pressure is relatively high, thereby reliably achieving the above-mentioned effect.

[0154] Figure 18 An enlarged view of the outer second intermediate tool groove 46 and the inner second intermediate tool groove 47 is shown. Figure 18 As shown, in the inclined surface 46s of the outer second intermediate kerf groove 46, the width W16 at the end of the first longitudinal edge 14a side is preferably greater than the width W17 at the end of the second longitudinal edge 14b side. The width W16 of the inclined surface 46s is, for example, 2.5 to 5.0 times the width W17. Furthermore, in the inclined surface 47s of the inner second intermediate kerf groove 47, the width W18 at the end of the second longitudinal edge 14b side is greater than the width W19 at the end of the first longitudinal edge 14a side. The width W18 of the inclined surface 47s is, for example, 1.5 to 4.0 times the width W19. This allows for superior grip performance.

[0155] The width W18 of the inclined surface 47s of the inner second intermediate cutting groove 47 is preferably smaller than the width W16 of the inclined surface 46s of the outer second intermediate cutting groove 46. Specifically, the width W18 is 40% to 60% of the width W16.

[0156] like Figure 17 as well as Figure 18 As shown, the maximum width of the inclined surface 31s of the outer first intermediate cutting groove 31 and the maximum width of the inclined surface 47s of the inner second intermediate cutting groove 47 are preferably 0.5 to 2.5 mm. Furthermore, the maximum depth of the inclined surface 31s of the outer first intermediate cutting groove 31 and the maximum depth of the inclined surface 47s of the inner second intermediate cutting groove 47 are preferably 0.5 to 2.5 mm. The maximum width of the inclined surface 32s of the inner first intermediate cutting groove 32 and the maximum width of the inclined surface 46s of the outer second intermediate cutting groove 46 are preferably 1.5 to 3.5 mm. Furthermore, the maximum depth of the inclined surface 32s of the inner first intermediate cutting groove 32 and the maximum depth of the inclined surface 46s of the outer second intermediate cutting groove 46 are preferably 1.5 to 3.5 mm. However, the dimensions of each inclined surface are not limited to these ranges.

[0157] In a further preferred embodiment, the maximum depth of the inclined surface 32s of the inner first intermediate sipe 32 and the maximum depth of the inclined surface 46s of the outer second intermediate sipe 46 are preferably greater than the maximum depth of the inclined surface 31s of the outer first intermediate sipe 31 and the maximum depth of the inclined surface 47s of the inner second intermediate sipe 47. This further improves the grip performance.

[0158] like Figure 16 As shown, neither the outer tread groove 41 nor the inner tread groove 42 has a widened portion. That is, in this embodiment, the outer tread groove 41 and the inner tread groove 42 have... Figure 7 The cross-sectional shape shown is formed with a constant width from the opening end toward the bottom.

[0159] Figure 19 Show Figure 15 Enlarged views of the first shoulder land portion 11 and the second shoulder land portion 15 of the illustrated embodiment. Figure 19 As shown, in this embodiment, the first shoulder land portion 11 is provided with a plurality of first shoulder transverse grooves 28 and a plurality of first shoulder slit grooves 21.

[0160] The first shoulder lateral groove 28 extends, for example, from the first shoulder circumferential groove 5 to at least the first tread end T1. The first shoulder lateral groove 28 is inclined, for example, in the second direction described above, relative to the tire axial direction. The angle of the first shoulder lateral groove 28 relative to the tire axial direction is, for example, 5 to 15°. Such a first shoulder lateral groove 28 helps to improve wet road performance.

[0161] The first shoulder groove 21 is inclined in a second direction, for example, relative to the tire axial direction. The first shoulder groove 21 extends, for example, along the first shoulder transverse groove 28, and in a preferred embodiment, they are arranged in parallel. Furthermore, in this embodiment, the first shoulder groove 21 extends, for example, from the periphery of the first shoulder towards the groove 5 and is interrupted within the first shoulder land portion 11. The tire axial length L24 of the first shoulder groove 21 is, for example, 40% to 60% of the tire axial width W20 of the tread of the first shoulder land portion 11. Such a first shoulder groove 21 helps to improve ride comfort and noise performance in a balanced way.

[0162] The first shoulder sipe 21 has, in the cross-section of the sipe, a feature similar to... Figure 6 The structure shown is the same as the one described above. That is, as... Figure 6 As shown, the first shoulder groove 21 includes a main body extending radially along the tire and a tread opening on the land portion, and a widened portion having a width greater than that of the main body. Furthermore, the widened portion includes an inclined surface extending from the main body to the tread. These structures can utilize the aforementioned configuration.

[0163] like Figure 19As shown, in this embodiment, inclined surfaces 21s are arranged on both sides of the edge of the first shoulder sipe 21. Furthermore, each inclined surface 21s is arranged throughout the length of the first shoulder sipe 21. Additionally, the width of the inclined surfaces 21s of the first shoulder sipe 21 increases towards the axial direction of the tire. The first shoulder sipe 21 with such inclined surfaces 21s helps to improve grip performance.

[0164] The maximum width W21 of the inclined surface 21s of the first shoulder sipe 21 is preferably greater than the aforementioned width W12 of the inclined surface 31s of the outer first intermediate sipe 31. Figure 17 As shown), and smaller than the aforementioned width W14 of the inclined surface 32s of the inner first intermediate groove 32 (as shown). Figure 17 (As shown). Specifically, the width W21 of the inclined surface 21s of the first shoulder groove 21 is 60% to 90% of the width W14 of the inclined surface 32s of the inner first intermediate groove 32. Thus, in the first shoulder land portion 11 and the first intermediate land portion 12 (… Figure 15 As shown in the figure, a uniform grounding pressure can be easily applied, thereby further improving the grip performance.

[0165] In this embodiment, the second shoulder land portion 15 is provided with a plurality of second shoulder lateral grooves 38 and a plurality of second shoulder sipes 50. The second shoulder lateral grooves 38 and the second shoulder sipes 50 are inclined relative to the tire axial direction in the second direction described above, and in a preferred embodiment, they are arranged in parallel.

[0166] The second shoulder lateral groove 38 extends at least from the second tread end T2 inwards along the tire axial direction and is interrupted within the second shoulder land portion 15. The tire axial length L25 of the second shoulder lateral groove 38 is, for example, 60% to 90% of the tire axial width W22 of the tread of the second shoulder land portion 15.

[0167] In this embodiment, the second shoulder cutter groove 50 does not have a widened portion. That is, the second shoulder cutter groove 50 in this embodiment has... Figure 7 The cross-sectional shape shown is formed with a constant width from the opening end toward the bottom.

[0168] like Figure 19 As shown, the second shoulder groove 50 of this embodiment includes a transverse second shoulder groove 51 and a connecting second shoulder groove 55. The transverse second shoulder groove 51 completely traverses the second shoulder land portion 15 in the tire axial direction. The connecting second shoulder groove 55 extends from the interrupted end 38a of the second shoulder transverse groove 38 to the second shoulder circumferential groove 8, connecting the second shoulder transverse groove 38 and the second shoulder circumferential groove 8. Such a second shoulder groove 50 helps to improve noise performance and ride comfort in a balanced way.

[0169] In this embodiment, transverse grooves are provided on the first shoulder land portion 11 and the second shoulder land portion 15, but instead of these transverse grooves, sipes may also be provided. In this case, the pumping noise of the transverse grooves is not generated, thereby further improving noise performance.

[0170] The tire according to one embodiment of the present invention has been described in detail above, but the present invention is not limited to the specific embodiment described above and can be implemented in various ways.

[0171] Example

[0172] Based on the specifications in Tables 1 and 2, a prototype with [specifications] was manufactured. Figure 1 The basic tread pattern is for a 235 / 55R19 tire. Additionally, a prototype tire with [specific tread pattern] was manufactured as a benchmark tire (reference tire) for comparing noise performance. Figure 15 The tire with the pattern shown.

[0173] Each land section of this reference tire is equipped with a... Figure 1 The tread pattern is obtained by removing the widened portion from the sipe shown. Furthermore, for the reference tire, the width Wa of the first shoulder land portion a and the width We of the second shoulder land portion e are the same. Additionally, the width Wb of the first intermediate land portion b, the width Wc of the crown land portion c, and the width Wd of the second intermediate land portion d are the same. Furthermore, the widths Wa and We are greater than the widths Wb, Wc, and Wd. Therefore, when the reference tire is loaded with a 50% load, and the widths of the contact surfaces along the tire axial direction of the first shoulder land portion a, the first intermediate land portion b, the crown land portion c, the second intermediate land portion d, and the second shoulder land portion e are set to W1s, W1m, Wc, W2m, and W2s respectively, the following formula (4) is satisfied.

[0174] W1s=W2s>W1m=Wc=W2m…(4)

[0175] In addition, as a comparative example, a prototype with... Figure 16 The tire with the pattern shown. The width distribution of the land portion of the comparative example tire is the same as that of the reference tire, and, with... Figure 1 Similarly, each cutting groove is provided with a widened portion. The comparative example tire, in addition to the above-mentioned aspects, is similar to... Figure 1 The items shown are essentially the same. The ride comfort and noise performance of each test tire were tested. The general specifications and test methods for each test tire are as follows.

[0176] Wheel rim installation: 19×7.0J

[0177] Tire internal pressure: 230 kPa

[0178] Test vehicle: 2000cc engine, four-wheel drive

[0179] Tire mounting location: All wheels

[0180] <Ride comfort>

[0181] The ride comfort of the test vehicle on ordinary roads was evaluated by the driver's senses. The results were scored with the ride comfort of the comparative example set at 100; the higher the score, the better the ride comfort.

[0182] Noise Performance

[0183] The test vehicle was driven on a dry road surface at speeds of 40–100 km / h, and the maximum sound pressure level inside the vehicle was measured. The results were expressed as the difference in sound pressure level between the comparative example and the reference tire, i.e., the reduction in sound pressure level, using an index where the improvement in sound pressure level of the comparative example is 100. The larger the index, the lower the maximum sound pressure level, indicating superior noise performance.

[0184] The test results are shown in Tables 1 and 2.

[0185] Table 1

[0186]

[0187] Table 2

[0188]

[0189] Table 3

[0190]

[0191] The test results confirm that the tires in this embodiment improve ride comfort and noise performance.

[0192] [Remark]

[0193] The present invention includes the following methods.

[0194] [Invention 1]

[0195] A tire having a tread portion indicating a direction of installation toward a vehicle, characterized in that the tread portion includes: a first tread end that becomes the outer side of the vehicle when installed in the vehicle; a second tread end that becomes the inner side of the vehicle when installed in the vehicle; four circumferential grooves extending continuously in the tire circumferential direction between the first tread end and the second tread end; and five land portions divided by the circumferential grooves.

[0196] Each of the five land sections is provided with a cutter groove.

[0197] The five land portions include: a first shoulder land portion including the first tread end, a second shoulder land portion including the second tread end, a first intermediate land portion adjacent to the first shoulder land portion, a second intermediate land portion adjacent to the second shoulder land portion, and a crown land portion between the first intermediate land portion and the second intermediate land portion.

[0198] When a standard inner pressure rim is assembled on a regular rim and a 50% standard load is applied with the ground plane at a 0° camber angle, and the widths of the contact surfaces of the first shoulder land portion, the first intermediate land portion, the crown land portion, the second intermediate land portion, and the second shoulder land portion are respectively set as W1s, W1m, Wc, W2m, and W2s, the following formula (1) is satisfied.

[0199] W1s>W1m>Wc>W2m≥W2s…(1).

[0200] [Invention 2]

[0201] The tire according to the present invention 1 is characterized in that,

[0202] The five land sections are each provided with only the aforementioned cutter groove.

[0203] [Invention 3]

[0204] The tire according to invention 1 or 2 is characterized in that,

[0205] The first intermediate land portion includes: a first longitudinal edge on the first tread end side, a second longitudinal edge on the second tread end side, and a tread surface between the first longitudinal edge and the second longitudinal edge.

[0206] Multiple first intermediate cutter grooves are provided in the first intermediate land portion.

[0207] The first intermediate cutting groove includes: an outer first intermediate cutting groove that communicates with the first longitudinal edge and has an interrupted end within the first intermediate land portion, and an inner first intermediate cutting groove that communicates with the second longitudinal edge and has an interrupted end within the first intermediate land portion.

[0208] [Invention 4]

[0209] The tire according to the present invention 3 is characterized in that,

[0210] The interrupted end of the outer first intermediate sipe and the interrupted end of the inner first intermediate sipe are misaligned along the tire circumferential direction.

[0211] [Invention 5]

[0212] The tire according to invention 3 or 4 is characterized in that,

[0213] The outer first intermediate sipe extends in a straight line at an angle relative to the tire axial direction and has a length La in the tire axial direction.

[0214] The tire circumferential distance Lb between the interrupted end of the outer first intermediate sipe and the interrupted end of the inner first intermediate sipe is within the range of the following formula (2).

[0215] Lb=2La±1(mm)…(2).

[0216] [Invention 6]

[0217] The tire according to any one of claims 1 to 5 is characterized in that,

[0218] Under the condition of loading 50% load, the width of the tire axial contact surface of the first shoulder land portion is 115% to 125% of the width of the tire axial contact surface of the crown land portion.

[0219] [Invention 7]

[0220] The tire according to any one of claims 1 to 6 of the present invention is characterized in that,

[0221] Under the condition of loading 50% load, the axial width of the tire contact surface of the second shoulder land portion is 90% to 99% of the axial width of the tire contact surface of the crown land portion.

[0222] [Invention 8]

[0223] The tire according to any one of claims 1 to 7 of the present invention is characterized in that,

[0224] The first shoulder land portion is provided with a plurality of first shoulder grooves that extend in a wavy shape when viewed from above.

[0225] The second shoulder land portion is provided with a plurality of second shoulder grooves that extend in a wavy shape when viewed from above.

[0226] [Invention 9]

[0227] The tire according to the present invention 8 is characterized in that,

[0228] The first shoulder groove and the second shoulder groove extend in a wavy shape along the groove depth direction.

[0229] [Invention 10]

[0230] The tire according to invention 8 or 9 is characterized in that,

[0231] Multiple first intermediate cutter grooves are provided in the first intermediate land portion.

[0232] Multiple second intermediate cutter grooves are provided in the second intermediate land portion.

[0233] The two groove walls of the first intermediate groove and the second intermediate groove are respectively formed as a plane.

[0234] [Invention 11]

[0235] The tire according to any one of claims 1 to 10 of the present invention is characterized in that,

[0236] A first pair of sipes is provided on the land portion of the first tire shoulder. The first pair of sipes is formed by two sipes that extend in a wavy shape and are spaced 6-12 mm apart along the tire axial direction.

[0237] A second pair of sipes is provided on the land portion of the second shoulder. The second pair of sipes is formed by two sipes that extend in a wavy shape and are spaced 6 to 12 mm apart along the tire axial direction.

[0238] [Invention 12]

[0239] The tire according to any one of claims 1 to 11 of the present invention is characterized in that,

[0240] Multiple first shoulder grooves are provided on the land portion of the first tire shoulder.

[0241] Multiple second shoulder grooves are provided on the land portion of the second tire shoulder.

[0242] The spacing length of one of the plurality of second shoulder grooves is less than the spacing length of one of the plurality of first shoulder grooves.

[0243] [Invention 13]

[0244] The tire according to any one of claims 1 to 12 of the present invention is characterized in that,

[0245] The second shoulder groove includes: a transverse second shoulder groove that completely traverses the second shoulder land portion along the tire axial direction, and an interrupted second shoulder groove that extends at least from the second tread end along the tire axial direction and has an interrupted end within the second shoulder land portion.

[0246] [Invention 14]

[0247] The tire according to any one of claims 1 to 13 of the present invention is characterized in that,

[0248] The four circumferential grooves include the first shoulder circumferential groove located on the side closest to the first tread end.

[0249] The first shoulder circumferential groove has the smallest groove width among the four circumferential grooves.

[0250] [Invention 15]

[0251] The tire according to the present invention 14 is characterized in that,

[0252] The four circumferential grooves include a first crown circumferential groove that is adjacent to the inner side of the tire axial direction of the first shoulder circumferential groove.

[0253] The first circumferential groove of the tire crown has the second smallest groove width among the four circumferential grooves.

[0254] [Invention 16]

[0255] The tire according to any one of claims 1 to 15 of the present invention is characterized in that,

[0256] The first intermediate land portion includes: a first longitudinal edge on the first tread end side, a second longitudinal edge on the second tread end side, and a tread surface between the first longitudinal edge and the second longitudinal edge.

[0257] Multiple first intermediate cutter grooves are provided in the first intermediate land portion.

[0258] The aforementioned first intermediate cutting groove includes an outer first intermediate cutting groove that communicates with the aforementioned first longitudinal edge and has an interrupted end within the aforementioned first intermediate land portion, and an inner first intermediate cutting groove that communicates with the aforementioned second longitudinal edge and has an interrupted end within the aforementioned first intermediate land portion.

[0259] The outer first intermediate sipe and the inner first intermediate sipe each include: a main body extending radially along the tire, and a widened portion having a tread opening in the first intermediate land portion and having a width greater than the main body.

[0260] The widened portion includes an inclined surface extending from the main body to the tread.

[0261] [Invention 17]

[0262] The tire according to the present invention 16 is characterized in that,

[0263] In the inclined surface of the first intermediate cutting groove on the outer side, the width at the end of the first longitudinal edge side is greater than the width at the end of the second longitudinal edge side.

[0264] In the inclined surface of the first intermediate groove on the inner side, the width at the end of the second longitudinal edge side is greater than the width at the end of the first longitudinal edge side.

[0265] [Invention 18]

[0266] The tire according to invention 16 or 17 is characterized in that,

[0267] The width at the end of the first longitudinal edge side of the inclined surface of the outer first intermediate cutting groove is smaller than the width at the end of the second longitudinal edge side of the inclined surface of the inner first intermediate cutting groove.

[0268] [Invention 19]

[0269] The tire according to the present invention 18 is characterized in that,

[0270] The width at the end of the first longitudinal edge side of the inclined surface of the outer first intermediate cutting groove is 40% to 60% of the width at the end of the second longitudinal edge side of the inclined surface of the inner first intermediate cutting groove.

[0271] [Invention 20]

[0272] The tire according to any one of claims 1 to 19 of the present invention is characterized in that,

[0273] A plurality of first shoulder grooves extending along the tire axial direction are provided on the land portion of the first shoulder.

[0274] The first tire shoulder groove includes: a main body extending radially along the tire, and a widened portion having a tread opening in the land portion of the first tire shoulder and having a width greater than the main body.

[0275] The widened portion of the first tire shoulder groove includes an inclined surface extending from the main body to the tread surface.

[0276] The width of the inclined surface of the first shoulder groove increases toward the axial inward side of the tire.

Claims

1. A tire having a tread portion which is provided with a direction of mounting to a vehicle, characterized by comprising: a first tread end which becomes an outer side of a vehicle at the time of mounting to the vehicle, a second tread end which becomes an inner side of the vehicle at the time of mounting to the vehicle, four circumferential grooves which continuously extend between the first tread end and the second tread end along a tire circumferential direction, and five land portions which are divided by the circumferential grooves, a sipe is provided in each of the five land portions, the five land portions include a first shoulder land portion which includes the first tread end, a second shoulder land portion which includes the second tread end, a first intermediate land portion which is adjacent to the first shoulder land portion, a second intermediate land portion which is adjacent to the second shoulder land portion, and a crown land portion which is between the first intermediate land portion and the second intermediate land portion, in a state where the tire is assembled to a regular rim with a standard inner pressure, is mounted to the regular rim, and is loaded with a 50% load which is flat with a 0° camber angle, when widths of land surfaces in a tire axial direction of the first shoulder land portion, the first intermediate land portion, the crown land portion, the second intermediate land portion, and the second shoulder land portion are set as Wls, Wlm, Wc, W2m, and W2s respectively, the following formula (1) is satisfied, Wls > Wlm > Wc > W2m > W2s... (1), the first intermediate land portion includes a first longitudinal edge on the first tread end side, a second longitudinal edge on the second tread end side, and a tread surface between the first longitudinal edge and the second longitudinal edge, a plurality of first intermediate sipes are provided in the first intermediate land portion, the first intermediate sipes include an outer side first intermediate sipe which communicates with the first longitudinal edge and has a discontinuous end within the first intermediate land portion, and an inner side first intermediate sipe which communicates with the second longitudinal edge and has a discontinuous end within the first intermediate land portion, the outer side first intermediate sipe and the inner side first intermediate sipe each include a main portion which extends along a tire radial direction, and a widened portion which opens at the tread surface of the first intermediate land portion and has a width which is larger than that of the main portion, the widened portion includes an inclined surface which extends from the main portion to the tread surface, a width at an end portion of the first longitudinal edge side in the inclined surface of the outer side first intermediate sipe is smaller than a width at an end portion of the second longitudinal edge side in the inclined surface of the inner side first intermediate sipe.

2. The tire according to claim 1, wherein only the sipes are provided in each of the five land portions.

3. The tire according to claim 1, wherein the discontinuous end of the outer side first intermediate sipe is displaced from the discontinuous end of the inner side first intermediate sipe in the tire circumferential direction.

4. The tire according to claim 1 or 3, wherein the outer side first intermediate sipe extends in a straight line obliquely with respect to the tire axial direction, and has a length La in the tire axial direction. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The distance Lb in the tire circumferential direction between the interrupted end of the outer first intermediate gash and the interrupted end of the inner first intermediate gash is in the range of the following formula (2), Lb = 2La ± 1 (mm) (2).

5. The tire according to any one of claims 1 to 3, wherein In the state where the 50% load is applied, the width of the ground surface of the first shoulder land portion in the tire axial direction is 115% to 125% of the width of the ground surface of the crown land portion in the tire axial direction.

6. The tire according to any one of claims 1 to 3, wherein In the state where the 50% load is applied, the width of the ground surface of the second shoulder land portion in the tire axial direction is 90% to 99% of the width of the ground surface of the crown land portion in the tire axial direction.

7. The tire according to any one of claims 1 to 3, wherein A plurality of first shoulder gashes extending in a wavy manner when the tread is viewed from above are provided in the first shoulder land portion, A plurality of second shoulder gashes extending in a wavy manner when the tread is viewed from above are provided in the second shoulder land portion.

8. The tire according to claim 7, wherein The first shoulder gashes and the second shoulder gashes each extend in a wavy manner in the gash depth direction.

9. The tire according to claim 7, wherein A plurality of second intermediate gashes are provided in the second intermediate land portion, The two gash walls of each of the first intermediate gashes and the second intermediate gashes are configured in a planar shape.

10. The tire according to any one of claims 1 to 3, wherein A first gash pair is provided in the first shoulder land portion, the first gash pair being formed by two gashes extending in a wavy manner and being arranged side by side with a distance of 6 to 12 mm in the tire axial direction, A second gash pair is provided in the second shoulder land portion, the second gash pair being formed by two gashes extending in a wavy manner and being arranged side by side with a distance of 6 to 12 mm in the tire axial direction.

11. The tire according to any one of claims 1 to 3, wherein A plurality of first shoulder gashes are provided in the first shoulder land portion, A plurality of second shoulder gashes are provided in the second shoulder land portion, One pitch length of the plurality of second shoulder gashes is smaller than one pitch length of the plurality of first shoulder gashes.

12. The tire according to any one of claims 1 to 3, wherein A plurality of second shoulder gashes are provided in the second shoulder land portion, The second shoulder gashes include a traverse second shoulder gash that completely traverses the second shoulder land portion in the tire axial direction, and an interrupted second shoulder gash that extends from at least the second tread end in the tire axial direction and has an interrupted end within the second shoulder land portion.

13. The tire according to any one of claims 1 to 3, wherein The four circumferential grooves include a first shoulder circumferential groove provided on the most first-tread-end side, The first shoulder circumferential groove has the smallest groove width among the four circumferential grooves.

14. The tire according to claim 13, wherein The four circumferential grooves include a first crown circumferential groove adjacent to a tire axial inner side of the first shoulder circumferential groove, The first crown circumferential groove has a second smallest groove width among the four circumferential grooves.

15. The tire according to claim 1, wherein In the inclined surface of the outer first intermediate sipe, the width at the end of the first longitudinal edge side is greater than the width at the end of the second longitudinal edge side, In the inclined surface of the inner first intermediate sipe, the width at the end of the second longitudinal edge side is greater than the width at the end of the first longitudinal edge side.

16. The tire according to claim 1, wherein The width at the end of the first longitudinal edge side in the inclined surface of the outer first intermediate sipe is 40% to 60% of the width at the end of the second longitudinal edge side in the inclined surface of the inner first intermediate sipe.

17. The tire according to any one of claims 1 to 3, wherein A plurality of first shoulder sipes extending in a tire axial direction are provided in the first shoulder land portion, The first shoulder sipe includes a main portion extending in a tire radial direction, and a widened portion opening to a tread surface of the first shoulder land portion and having a width greater than that of the main portion, The widened portion of the first shoulder sipe includes an inclined surface extending from the main portion to the tread surface, The width of the inclined surface of the first shoulder sipe increases toward a tire axial inner side.

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