JP7115077B2 - pneumatic tire - Google Patents

Description

TECHNICAL FIELD The present invention relates to a pneumatic tire, and more particularly to a pneumatic tire capable of achieving both dry performance and wet performance.

In recent years, pneumatic tires have been required to improve sports performance not only for circuit driving, but also for city driving and highway driving. Therefore, in order to achieve both dry performance and wet performance of the tire, two circumferential main grooves are provided in the vehicle width direction inner region bounded by the tire equatorial plane, and a single circumferential main groove is provided in the vehicle width direction outer region. A configuration is employed that includes a main groove and a single circumferential narrow groove. As a conventional pneumatic tire adopting such a configuration, the technology described in Patent Document 1 is known.

Further, Patent Document 2 describes a conventional pneumatic tire that adopts a configuration in which sipes passing through circumferential grooves and narrow grooves passing through circumferential grooves and having one end terminated in a land portion are alternately arranged. technology is known.

JP 2016-74386 A JP 2013-49407 A

An object of the present invention is to provide a pneumatic tire that achieves both dry performance and wet performance.

In order to achieve the above object, a pneumatic tire according to one aspect of the present invention includes a circumferential groove extending in the tire circumferential direction, and extending in the tire width direction, penetrating the circumferential groove and extending at both ends. a plurality of through grooves terminating in a land portion, and in at least one side region of the circumferential groove in the tire width direction, the narrowest groove width Wg_min and the widest width of the through groove among the plurality of through grooves. The groove width Wg_max of the through groove has a relationship of 1.50≦Wg_max/Wg_min≦20.0. Further, in at least one side region in the tire width direction of the circumferential groove, the groove width of the plurality of through grooves is 1.5 mm or more, and among the plurality of through grooves, the narrowest through groove The groove width Wg_min of the groove and the groove width Wg_max of the widest through groove have a relationship of 1.50≦Wg_max/Wg_min≦3.00.

In the pneumatic tire according to the present invention, (1) the through grooves penetrate through the circumferential narrow grooves, thereby improving the drainage performance in the vicinity of the circumferential narrow grooves and improving the wet performance of the tire. At the same time, since the through groove does not open to the circumferential main groove and the tire contact edge, the rigidity of the left and right land portions defined by the circumferential narrow grooves is ensured. As a result, there is an advantage that wet performance and dry performance of the tire are efficiently compatible. In addition, (2) since a plurality of types of through grooves having mutually different groove widths are arranged at predetermined intervals in the tire circumferential direction, the plurality of types of through grooves 41 all have the same groove width and the same length. Then, a through groove with a wide groove width is arranged on the tread surface of one land portion. As a result, there is an advantage that the dry performance and wet performance of the tire can be improved in a well-balanced manner.

FIG. 1 is a cross-sectional view of a pneumatic tire according to an embodiment of the invention taken along the tire meridian line. 2 is a plan view showing the tread surface of the pneumatic tire shown in FIG. 1. FIG. FIG. 3 is an enlarged view showing a main portion of the vehicle width direction outer region of the pneumatic tire shown in FIG. FIG. 4 is an explanatory diagram showing through grooves of the pneumatic tire shown in FIG. FIG. 5 is an explanatory diagram showing a modification of the through groove shown in FIG. FIG. 6 is an explanatory diagram showing a modification of the through groove shown in FIG. FIG. 7 is an explanatory diagram showing a modification of the through groove shown in FIG. FIG. 8 is an explanatory diagram showing a modification of the through groove shown in FIG. FIG. 9 is an explanatory diagram showing a modification of the through groove shown in FIG. FIG. 10 is an explanatory diagram showing a modified example of the through groove shown in FIG. FIG. 11 is a diagram showing a case where both the vehicle width direction inner side and the vehicle width direction outer side of the circumferential narrow groove are sipes. FIG. 12 is a diagram showing a case where both the vehicle width direction inner side and the vehicle width direction outer side of the circumferential narrow groove are sipes. FIG. 13 is a diagram showing a case where both the vehicle width direction inner side and the vehicle width direction outer side of the circumferential narrow groove are sipes. FIG. 14 is a chart showing results of performance tests of the pneumatic tire according to the embodiment of the invention. FIG. 15 is a chart showing results of performance tests of the pneumatic tire according to the embodiment of the invention. FIG. 16 is a chart showing results of performance tests of the pneumatic tire according to the embodiment of the invention.

BEST MODE FOR CARRYING OUT THE INVENTION Below, embodiments of the present invention will be described in detail based on the drawings. In the description of each embodiment below, the same reference numerals are given to components that are the same as or equivalent to those of other embodiments, and description thereof will be simplified or omitted. The present invention is not limited by each embodiment. In addition, the components of each embodiment include those that can be easily replaced by those skilled in the art, or those that are substantially the same. Also, the configurations described below can be combined as appropriate. Note that omissions, substitutions, or changes in configuration can be made without departing from the gist of the invention.

[Pneumatic tire]
FIG. 1 is a cross-sectional view of a pneumatic tire according to an embodiment of the present invention taken along the tire meridian line. FIG. 1 shows a cross-sectional view of one side region in the tire radial direction. Moreover, FIG. 1 shows a radial tire for a passenger car as an example of a pneumatic tire.

In FIG. 1, the cross section in the tire meridian direction refers to a cross section obtained by cutting the tire along a plane including the tire rotation axis (not shown). Further, the symbol CL is the tire equatorial plane, which is a plane perpendicular to the tire rotation axis passing through the center point of the tire in the tire rotation axis direction. Moreover, the tire width direction refers to the direction parallel to the tire rotation axis, and the tire radial direction refers to the direction perpendicular to the tire rotation axis.

In addition, the vehicle width direction inner side and the vehicle width direction outer side are defined as directions with respect to the vehicle width direction when the tire is mounted on the vehicle. In addition, regions on the left and right sides of the tire equatorial plane are defined as a vehicle width direction outer region and a vehicle width direction inner region, respectively. In addition, the pneumatic tire has a mounting direction indicator (not shown) that indicates the tire mounting direction with respect to the vehicle. The mounting direction display portion is configured by, for example, a mark or unevenness attached to the sidewall portion of the tire. For example, ECER30 (Economic Commission Regulations for Europe, Article 30) obliges the provision of a vehicle installation direction indicator on a sidewall portion that is located outside in the vehicle width direction when the vehicle is installed.

The pneumatic tire 10 has an annular structure around the tire rotation axis, and includes a pair of bead cores 11, 11, a pair of bead fillers 12, 12, a carcass layer 13, a belt layer 14, and a tread rubber 15. , a pair of sidewall rubbers 16, 16 and a pair of rim cushion rubbers 17, 17 (see FIG. 1).

A pair of bead cores 11, 11 are formed by winding one or a plurality of steel bead wires in a ring-shaped manner, and are embedded in the bead portions to constitute the cores of the left and right bead portions. The pair of bead fillers 12, 12 are arranged on the tire radial direction outer peripheries of the pair of bead cores 11, 11, respectively, to reinforce the bead portions.

The carcass layer 13 has a single layer structure consisting of one carcass ply or a multilayer structure consisting of a plurality of laminated carcass plies. configure. Further, both ends of the carcass layer 13 are wound back outward in the tire width direction so as to wrap the bead core 11 and the bead filler 12 and are locked. The carcass plies of the carcass layer 13 are formed by coating a plurality of carcass cords made of steel or organic fiber material (for example, aramid, nylon, polyester, rayon, etc.) with a coating rubber and rolling them. It has a carcass angle (defined as an inclination angle of the longitudinal direction of the carcass cords with respect to the tire circumferential direction) of [deg] or more and 90 [deg] or less.

The belt layer 14 is formed by laminating a pair of cross belts 141 and 142 and a belt cover 143, and is arranged around the outer periphery of the carcass layer 13. As shown in FIG. The pair of cross belts 141 and 142 is constructed by coating a plurality of belt cords made of steel or organic fiber material with coat rubber and rolling the cords, and has a belt angle of 20 [deg] or more and 55 [deg] or less in absolute value. have. The pair of cross belts 141 and 142 have belt angles of opposite signs (defined as inclination angles of the longitudinal direction of the belt cords with respect to the tire circumferential direction), and the longitudinal directions of the belt cords intersect each other. laminated together (so-called cross-ply structure). The belt cover 143 is configured by coating a belt cover cord made of steel or an organic fiber material with a coat rubber, and has a belt angle of 0 [deg] or more and 10 [deg] or less in absolute value. The belt cover 143 is, for example, a strip material formed by coating one or more belt cover cords with a coating rubber. It may be configured with a turn and spiral wrap.

The tread rubber 15 is arranged on the outer periphery of the carcass layer 13 and the belt layer 14 in the tire radial direction to constitute the tread portion of the tire. A pair of sidewall rubbers 16, 16 are arranged outside the carcass layer 13 in the tire width direction, respectively, and constitute left and right sidewall portions. The pair of rim cushion rubbers 17, 17 are arranged radially inside the left and right bead cores 11, 11 and the turn-up portions of the carcass layer 13, respectively, to form rim fitting surfaces 20 of the bead portions.

[Tread pattern]
FIG. 2 is a plan view showing the tread surface of the pneumatic tire 10 shown in FIG. 1. FIG. FIG. 2 shows the tread pattern of an all-season tire. In FIG. 2, the tire circumferential direction refers to the direction around the tire rotation axis. Further, the symbol T is the tire contact edge, and the dimension symbol TW is the tire contact width.

As shown in FIG. 2, the pneumatic tire 10 includes a plurality of circumferential main grooves 21 to 23 and a plurality of circumferential narrow grooves 24 extending in the tire circumferential direction, and a plurality of grooves partitioned by these circumferential grooves 21 to 24. land portions 31 to 35 are provided on the tread surface.

A main groove is a groove that is required to display a wear indicator defined by JATMA, and generally has a groove width of 3.0 [mm] or more and a groove depth of 6.0 [mm] or more. A through groove is a lateral groove extending in the tire width direction. The through grooves include lug grooves and sipes, which will be described later. The lug groove is open when the tire touches the ground and functions as a groove. The groove width of the lug is, for example, 1.5 [mm] or more. A sipe is a cut formed in the tread surface, and is distinguished from a lug groove in that it closes when the tire touches the ground.

Note that the circumferential narrow grooves 24 will be described later.

The groove width is measured as the maximum value of the distance between the left and right groove walls at the opening of the groove in an unloaded state in which the tire is mounted on a specified rim and filled with a specified internal pressure. In a configuration in which the land portion has a notch portion or a chamfered portion at the edge portion, the groove width is measured by using the intersection of the tread surface and the extension line of the groove wall as a measurement point in a cross-sectional view with the groove length direction as the normal direction. is measured. In addition, in a structure in which the groove extends in a zigzag or wavy shape in the tire circumferential direction, the groove width is measured using the center line of the amplitude of the groove wall as the measurement point.

Groove depth is measured as the maximum distance from the tread surface to the groove bottom when the tire is mounted on a specified rim and filled with a specified internal pressure in an unloaded state. In addition, in a configuration in which the groove has partial irregularities or sipes at the groove bottom, the groove depth is measured excluding these.

A specified rim means a "standard rim" specified by JATMA, a "design rim" specified by TRA, or a "measuring rim" specified by ETRTO. In addition, the prescribed internal pressure means the "maximum air pressure" prescribed by JATMA, the maximum value of "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES" prescribed by TRA, or "INFLATION PRESSURES" prescribed by ETRTO. Moreover, the specified load means the "maximum load capacity" specified by JATMA, the maximum value of "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES" specified by TRA, or the "LOAD CAPACITY" specified by ETRTO. However, according to JATMA, in the case of passenger car tires, the specified internal pressure is 180 [kPa] and the specified load is 88 [%] of the maximum load capacity.

For example, in the configuration of FIG. 2, the pneumatic tire 10 has a left-right asymmetrical tread pattern centered on the tire equatorial plane CL. In addition, the vehicle width direction inner region bounded by the tire equatorial plane CL has two circumferential main grooves 21 and 22, and the vehicle width direction outer region has one circumferential main groove 23 and one circumferential main groove. and narrow grooves 24 . Moreover, these circumferential grooves 21, 22; 23, 24 are arranged symmetrically with respect to the tire equatorial plane CL. Five rows of land portions 31 to 35 are defined by these circumferential grooves 21 to 24, respectively. One land portion 33 is arranged on the tire equatorial plane CL.

Further, the land portions 31 and 35 on the outer side in the tire width direction defined by the outermost circumferential main groove 21 in the inner region in the vehicle width direction or the narrow grooves 24 in the outer region in the vehicle width direction are defined as shoulder land portions. The shoulder land portions 31 and 35 are the outermost land portions in the tire width direction and are located on the tire ground contact edge T. As shown in FIG. Further, the land portions 32 and 34 on the inner side in the tire width direction defined by the outermost circumferential direction main groove 21 or the circumferential narrow grooves 24 are defined as second land portions. Therefore, the second land portions 32 and 34 are adjacent to the shoulder land portions 31 and 35 with the outermost circumferential main grooves 21 and 24 interposed therebetween. Further, the land portion 33 located closer to the tire equatorial plane CL than the second land portions 32 and 34 is defined as a center land portion.

[Vehicle width direction outer region]
In the configuration of FIG. 2 , the vehicle width direction outer region bounded by the tire equatorial plane CL is composed of a single circumferential main groove 23 and a single circumferential main groove 23 arranged outside the tire width direction outer side of the circumferential main groove 23 . Circumferential grooves 24 are provided. A shoulder land portion 35 and a second land portion 34 are defined by these circumferential grooves 23 and 24 .

For example, in the configuration of FIG. 2, the circumferential main groove 23 and the circumferential narrow grooves 24 have a straight shape with a constant groove width. Further, the distance Dm from the tire equatorial plane CL to the groove center line of the circumferential main groove 23 is in the range of 8% or more and 12% or less with respect to the tire contact width TW. Further, the distance Dn from the tire equatorial plane CL to the groove center line of the circumferential narrow groove 24 is in the range of 26% or more and 32% or less with respect to the tire contact width TW.

The groove centerline of the circumferential main groove is defined as a straight line parallel to the tire circumferential direction passing through the midpoint between the left and right measurement points of the groove width of the circumferential main groove.

The tire contact width TW is the contact surface between the tire and the flat plate when the tire is mounted on the specified rim, the specified internal pressure is applied, the tire is placed perpendicular to the flat plate in the stationary state, and the load corresponding to the specified load is applied. measured as the maximum linear distance in the axial direction of the tire.

The tire contact edge T is the contact surface between the tire and the flat plate when the tire is mounted on the specified rim, the specified internal pressure is applied, the tire is placed perpendicular to the flat plate in the stationary state, and a load corresponding to the specified load is applied. is defined as the position of maximum width in the axial direction of the tire.

Further, the groove width of the circumferential main groove 23 is in the range of 5.0 [mm] or more and 25.0 [mm] or less, and the groove depth is in the range of 5.0 [mm] or more and 12.0 [mm] or less. (Dimensional symbols omitted in the figure). Further, the groove width Ws (see FIG. 4 described later) of the circumferential narrow groove 24 is in the range of 3.0 [mm] to 7.0 [mm], and the groove depth is 3.0 [mm] to 7.0 [mm]. .0 [mm] or less (dimension symbols are omitted in the figure).

In addition, in the configuration of FIG. 2, the edge portions of the left and right land portions 33 and 34 partitioned by the circumferential main groove 23 in the vehicle width direction outer region on the side of the circumferential main groove 23 also serve as openings of the sipes and grooves. It extends continuously in the tire circumferential direction by having a plane structure that does not extend. This improves the noise performance of the tire.

[Through Groove in Outer Region in Vehicle Width Direction]
FIG. 3 is an enlarged view showing a main part of the vehicle width direction outer region of the pneumatic tire shown in FIG. FIG. 4 is an explanatory diagram showing through grooves of the pneumatic tire shown in FIG. In these figures, FIG. 3 shows the second land portion 34 and the shoulder land portion 35 in the vehicle width direction outside region, and FIG. there is

As shown in FIG. 2, the pneumatic tire 10 includes the above-described circumferential narrow grooves 24 and a plurality of through grooves 41 (41A, 41B) in the vehicle width direction outer region.

The through groove 41 extends in the tire width direction and penetrates the circumferential narrow groove 24 , and does not open to the circumferential main groove 23 and the tire grounding edge T, but inside the second land portion 34 and the shoulder land portion 35 . terminate. Therefore, the through grooves 41 are branched from the circumferential narrow grooves 24 in the tire width direction and terminate inside the left and right land portions 34 , 35 . Here, the terminal portion of the through groove 41 on the inner side in the tire width direction is simply referred to as the "inner terminal portion", and the terminal portion on the outer side in the tire width direction is simply referred to as the "outer terminal portion". A plurality of through grooves 41 (41A, 41B) are arranged at predetermined intervals in the tire circumferential direction.

In the above configuration, since the through grooves 41 penetrate the circumferential narrow grooves 24, the drainage performance in the vicinity of the circumferential narrow grooves 24 is improved, and the wet performance of the tire is improved. At the same time, since the through groove 41 does not open to the circumferential main groove 23 and the tire ground contact edge T, the rigidity of the left and right land portions 34 and 35 defined by the circumferential narrow groove 24 is ensured. As a result, wet performance and dry performance of the tire are efficiently compatible.

Further, as shown in FIG. 3, a plurality of types of through grooves 41 (41A, 41B) having mutually different extension lengths are arranged in a mixed manner. Further, among the plurality of types of through grooves 41, the extension length L1_min of the shortest through groove 41A and the extension length L1_max of the longest through groove 41B are 1.10≦L1_max/L1_min≦3. 00, and more preferably 1.20≦L1_max/L1_min≦1.60. The relationship between the groove width Wg1 of the shortest through groove 41A and the groove width Wg2 of the longest through groove 41B is Wg2>Wg1. The range of the extension length L1 of the through groove 41 is not particularly limited, but is restricted by the range of the distances Di and Do (see FIG. 4) of the end portions of the through groove 41 in the land portions 34 and 35, which will be described later. .

The extension length L1 of the through groove is the distance in the tire width direction from the inner end portion to the outer end portion of the through groove when the tire is mounted on a specified rim, the specified internal pressure is applied, and the tire is in a no-load state. Defined. In addition, in a configuration including three or more types of through-grooves having mutually different extension lengths, the extension length L1_min of the shortest first through-groove and the extension of the longest second through-groove The lengths L1_max and L1_max are respectively measured.

For example, in the configuration of FIG. 3, a plurality of through grooves 41 (41A, 41B) are arranged at predetermined intervals in the tire circumferential direction. Moreover, these through grooves 41A and 41B intersect only the circumferential narrow groove 24 and are not connected to other grooves or sipes. In addition, the second land portion 34 and the shoulder land portion 35 are not divided in the tire circumferential direction by lug grooves or sipes, and have tread surfaces that are continuous in the tire circumferential direction. The first and second through grooves 41A and 41B are arranged parallel to each other by inclining their longitudinal directions with respect to the tire circumferential direction in the same direction and at the same inclination angle. However, the inclination angles θ of the through-grooves 41A and 41B may differ within the range described later.

In FIG. 3, the contact widths W1 and W2 of the second land portion 34 and the shoulder land portion 35 preferably have a relationship of 1.00≤W2/W1≤2.00, and 1.20≤W2/W1≤. More preferably, it has a relationship of 1.40. Further, it is preferable that the contact width W1 of the second land portion 34 has a relationship of 0≦W1/TW≦0.30 with respect to the tire contact width TW. Thereby, the contact widths W1 and W2 of the left and right land portions 34 and 35 defined by the circumferential main groove 23 and the circumferential narrow groove 24 are optimized.

The contact width of the land part is the contact between the tire and the flat plate when the tire is mounted on the specified rim, the specified internal pressure is applied, and the load corresponding to the specified load is applied by placing the tire perpendicular to the flat plate in a stationary state. Measured as the maximum linear distance in the axial direction of the tire in the plane.

Moreover, a plurality of through grooves 41 (41A, 41B) are arranged with at least one terminal end thereof offset from each other in the tire width direction. At this time, the end portion of the through groove 41 may be offset on the second land portion 34 side (see FIG. 3), or may be offset on the shoulder land portion 35 side, or on the second land portion 34 side and the shoulder land portion as described later. Both sides of 35 may be offset. Moreover, a plurality of types of through grooves 41A and 41B having groove widths different from each other are arranged in a predetermined order in the tire circumferential direction. At this time, as shown in FIGS. 3 and 4, through grooves 41A and 41B having two types of groove widths may be alternately arranged in the tire circumferential direction, or three or more types of through grooves 41 may be arranged as described later. May be arranged. In the case where the through grooves 41A and 41B having two types of groove widths are alternately arranged in the tire circumferential direction, each of the plurality of through grooves is narrower than the groove width of the other through grooves adjacent to each other in the tire circumferential direction. means to have width. When the through-grooves 41A and 41B having two different groove widths are alternately arranged in the tire circumferential direction, each of the plurality of through-grooves has a groove width wider than that of other through-grooves adjacent to each other in the tire circumferential direction. means to have

[Through groove length]
4, the distance Di (including the minimum value Di_min and maximum value Di_max in FIG. 4) from the circumferential narrow groove 24 to the inner terminal end of the through groove 41 (41A, 41B), The contact width W1 (see FIG. 3) preferably has a relationship of 0.10≦Di/W1≦0.80, and more preferably has a relationship of 0.20≦Di/W1≦0.40. As a result, the extension length Di of the through groove 41 in the second land portion 34 in the tire width direction is optimized.

4, the distance Do (including the minimum value Do_min and the maximum value Do_max in FIG. 4) from the circumferential narrow groove 24 to the outer terminal end of the through groove 41 (41A, 41B), and the distance of the shoulder land portion 35 The contact width W2 (see FIG. 3) preferably has a relationship of 0.10≦Do/W2≦0.60, and more preferably has a relationship of 0.20≦Do/W2≦0.40. As a result, the extending length of the through groove 41 in the shoulder land portion 35 in the tire width direction is optimized.

The distances Di and Do to the terminal end of the through groove are the distances from the measurement points of the ground contact widths W1 and W2 of the land portion to the through groove when the tire is mounted on the specified rim, the specified internal pressure is applied, and the tire is in an unloaded state. Measured as the widthwise distance to the end of the tire. Also, in a configuration in which there are three or more types of distances Di and Do having mutually different numerical values, the distance Di; the maximum value Di_max; Do_max and the minimum value Di_min; Do_min of Do must satisfy the above conditions.

In FIG. 4, the minimum value Di_min and the maximum value Di_max of the distances Di of the inner end portions of the plurality of through grooves 41 (41A, 41B) have a relationship of 1.10≦Di_max/Di_min≦3.00. is preferable, and it is more preferable to have a relationship of 1.20≦Di_max/Di_min≦1.60. Further, the offset amount ΔDi in the tire width direction of the inner end portion of the through groove 41 satisfies the relationship of 0.10≦ΔDi/W1≦0.60 with respect to the contact width W1 (see FIG. 3) of the second land portion 34. It is preferable to have a relationship of 0.20≦ΔDi/W1≦0.40. Therefore, in the second land portion 34, the end portions of the through grooves 41A and 41B are arranged offset in the tire width direction. As a result, the positions of the inner end portions of the through grooves 41A and 41B in the second land portion 34 are optimized, and both the wet performance and the dry performance of the tire are achieved. In particular, since the second land portion 34 greatly contributes to the wet performance, the above configuration efficiently improves the wet performance of the tire.

On the other hand, it is preferable that the minimum value Do_min and the maximum value Do_max of the distance Do of the outer end portions of the plurality of through grooves 41 (41A, 41B) have a relationship of 0.90≦Do_max/Do_min≦1.10, It is more preferable to have a relationship of 0.95≤Do_max/Do_min≤1.05. Further, the offset amount ΔDo in the tire width direction of the outer terminal portion of the through groove 41 has a relationship of 0≦ΔDo/W2≦0.10 with respect to the contact width W2 (see FIG. 3) of the shoulder land portion 35. is preferable, and it is more preferable to have a relationship of 0≦ΔDo/W2≦0.05. Therefore, in the shoulder land portion 35, the end portions of the through grooves 41A and 41B are aligned in the tire width direction. As a result, the rigidity of the shoulder land portion 35 can be appropriately ensured, so that the dry braking performance of the tire is improved.

The offset amount ΔDi;ΔDo of the end portion of the through groove is calculated as the difference between the maximum value Di_max;Do_max and the minimum value Di_min;Do_min of the distance Di;Do from the circumferential narrow groove to the end portion.

Further, as shown in FIG. 4, a plurality of through grooves 41 (41A, 41B) are arranged with their longitudinal directions inclined in the same direction with respect to the tire circumferential direction. In addition, the inclination angle θ of the through groove 41 with respect to the tire circumferential direction is preferably in the range of 50 [deg] ≤ θ ≤ 80 [deg], and is in the range of 55 [deg] ≤ θ ≤ 75 [deg]. is more preferred. As a result, the drainage performance of the through grooves 41 is improved, and the tire pattern noise caused by the through grooves 41 is reduced.

The inclination angle θ of the through groove is measured as an angle formed between a straight line connecting both ends of the center line of the through groove and the tire circumferential direction.

Further, the inclination angle θ1 of the through groove 41 having the smallest inclination angle θ and the inclination angle θ2 of the through groove 41 having the largest inclination angle θ satisfy the relationship of 0 [deg]≦θ2−θ1≦10 [deg]. It is preferable to have 0 [deg] ≤ θ2 - θ1 ≤ 5 [deg]. That is, it is preferable that the inclination angle θ of the through groove 41 is substantially constant. As a result, the rigidity of the land portion can be appropriately ensured, so uneven wear is suppressed.

[Groove Width of Through Groove]
Further, the ratio of the groove width Wg of the through groove 41 to the groove width Ws of the circumferential narrow groove 24, that is, the ratio Wg/Ws of the groove width of each through groove to the groove width of the circumferential narrow groove 24 is It preferably has a relationship of 0.30≦Wg/Ws≦1.30, and more preferably has a relationship of 0.60≦Wg/Ws≦1.00. As a result, the drainage action of the through groove 41 is properly ensured.

Further, in at least one side region of the circumferential narrow groove 24 in the tire width direction, among the plurality of through grooves 41, the groove width Wg_min of the narrowest through groove and the groove width Wg_max of the widest through groove 41B are It is preferable to have a relationship of 1.50≤Wg_max/Wg_min≤20.0. By satisfying this condition, dry performance and wet performance can be improved in a well-balanced manner.

In a region on at least one side of the circumferential narrow groove 24 in the tire width direction, when the groove width of the plurality of through grooves 41 is 1.5 [mm] or more, among the plurality of through grooves 41, the narrowest through groove The groove width Wg_min of the groove 41A and the groove width Wg_max of the widest through groove 41B preferably have a relationship of 1.50≦Wg_max/Wg_min≦3.00. By satisfying this condition, dry performance and wet performance can be improved in a well-balanced manner.

Here, in the configuration of FIG. 4, the through groove 41 has a straight shape with a constant groove width as a whole, and has a tapered shape where the groove width is narrowed at the terminal end. Further, by narrowing the groove width in the same direction in the tire circumferential direction at the right and left end portions of the through groove 41, the entire through groove 41 has a trapezoidal shape having an upper base and a lower base in the tire circumferential direction. . Also, the plurality of through grooves 41A and 41B are aligned in the tire circumferential direction. However, not limited to this, the end portion of the through groove 41 may have a rectangular shape or an arc shape (not shown). Also, the entire through groove 41 may have a rectangular shape or a parallelogram shape (not shown).

[Shoulder lug grooves in outer region in vehicle width direction]
As shown in FIG. 2 , the shoulder land portion 35 in the vehicle width direction outer region includes a plurality of shoulder lug grooves 42 in the vehicle width direction outer region.

The shoulder lug groove 42 has one terminal end within the shoulder land portion 35 , extends in the tire width direction, and opens at the tire contact edge T. As shown in FIG. Moreover, the shoulder lug grooves 42 do not communicate with the circumferential narrow grooves 24 and the through grooves 41, and do not overlap in the tire width direction. A plurality of shoulder lug grooves 42 are arranged at predetermined intervals in the tire circumferential direction.

Further, as shown in FIG. 3, the elongated through groove 41B is on the extension line of the groove center line of the shoulder lug groove 42. As shown in FIG. Specifically, the groove center line of the shoulder lug groove 42 has a gentle arc shape, and the through groove 41B extends including an extension line of the groove center line of the shoulder lug groove 42 . In such a configuration, the shoulder lug grooves 42 extend along the extension of the through grooves 41B, thereby improving drainage from the second land portion 34 to the shoulder land portion 35 . In addition, not limited to the above, the short through groove 41A may be on an extension line of the groove center line of the shoulder lug groove 42 (not shown).

Further, as shown in FIG. 3, the shoulder lug grooves 42 are arranged so that the groove center lines of the through grooves 41 (41A, 41B) do not overlap the groove center lines of the shoulder lug grooves 42 in the tire circumferential direction. A positional relationship in the tire circumferential direction between the lug grooves 42 and the through grooves 41 is set. Specifically, distances D1A and D1B in the tire circumferential direction between the end of the groove center line of the through grooves 41A and 41B and the end of the groove center line of the shoulder lug groove 42 in FIG. It is set in the range of D1B. As a result, pattern noise caused by overlapping grooves is reduced, and quietness (noise performance) of the tire is improved.

The end of the groove centerline of the through groove is defined as the intersection of the terminal end of the opening of the through groove at the tread surface of the land portion and the groove centerline of the through groove.

Moreover, as shown in FIG. 3, the end portion of the shoulder lug groove 42 and the outer end portion of the through groove 41B facing the shoulder lug groove 42 are separated from each other in the tire width direction. Also, the shoulder lug groove 42 and the through groove 41B are not connected by another groove or sipe. In addition, the distance D2 in the tire width direction from the terminal end of the shoulder lug groove 42 to the outer terminal end of the through groove 41B and the contact width W2 of the shoulder land portion 35 satisfy 0.10≦D2/W2≦0.60. It is preferable to have a relationship of 0.30≦D2/W2≦0.50. As a result, wet performance and dry performance of the tire are compatible. That is, the above lower limit ensures the rigidity and ground contact area of the shoulder land portion 35, thereby ensuring the dry performance of the tire. Moreover, the above upper limit ensures that the through grooves 41 and the shoulder lug grooves 42 extend in the tire width direction, thereby ensuring the wet performance of the tire.

Furthermore, in the configuration of FIG. 3, the shoulder land portions 35 are divided into grooves or sipes in the regions between the end portions of all the shoulder lug grooves 42 and the outer end portions of all the through grooves 41 (41A, 41B). It has a plain tread surface that is continuous in the tire circumferential direction. That is, the shoulder lug grooves 42 and the through grooves 41 do not overlap each other in the tire width direction. This further improves the dry performance of the tire.

Further, in FIG. 3, it is preferable that the arrangement interval P1 of the through grooves 41 and the arrangement interval P2 of the shoulder lug grooves 42 in the tire circumferential direction have a relationship of 0.30≦P1/P2≦0.70. It is more preferable to have a relationship of 40≤P1/P2≤0.60. Thereby, the arrangement intervals P1 and P2 of the through grooves 41 and the shoulder lug grooves 42 are optimized. In the configuration shown in FIG. 3, a pair of through grooves 41A and 41B, which form a pair of short and long grooves, and one shoulder lug groove 42 are arranged in the tire circumferential direction with the same pitch length.

The arrangement intervals P1 and P2 of the through grooves 41 and the shoulder lug grooves 42 are measured using the intersection of the groove center line of each groove and the groove center line of the circumferential narrow groove or the tire contact edge as a measuring point.

[Modification]
5 to 10 are explanatory diagrams showing modifications of the through groove shown in FIG. In these figures, the same components as those shown in FIG. 4 are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIGS. 5 to 8, narrow through-grooves 41A and wide through-grooves 41B may not be arranged alternately in the tire circumferential direction. 5 to 8 show the case where the groove width of the plurality of through grooves 41 is 1.5 [mm] or more in at least one side region of the circumferential groove 24 in the tire width direction. In FIG. 5, the groove width Wg_min of the narrowest through-groove 41A and the groove width Wg_max of the widest through-groove 41B must satisfy the condition that the relationship of 1.50≦Wg_max/Wg_min≦3.00 is satisfied. For example, the minimum value Di_min and the minimum value Do_min may be substantially the same, and the maximum value Di_max may be greater than the maximum value Do_max. Further, in FIG. 6, if the groove width Wg_min of the narrowest through groove 41A and the groove width Wg_max of the widest through groove 41B satisfy the condition of 1.50≦Wg_max/Wg_min≦3.00, the maximum The value Do_max and the maximum value Di_max may be substantially the same, and the minimum value Di_min and the minimum value Do_min may be substantially the same. Furthermore, in FIG. 7, if the groove width Wg_min of the narrowest through groove 41A and the groove width Wg_max of the widest through groove 41B satisfy the condition of 1.50≦Wg_max/Wg_min≦3.00, the minimum The minimum value Di_min may be smaller than the value Do_min, and the maximum value Di_max may be greater than the maximum value Do_max. Further, in FIG. 8, if the groove width Wg_min of the narrowest through groove 41A and the groove width Wg_max of the widest through groove 41B satisfy the condition of 1.50≦Wg_max/Wg_min≦3.00, the maximum The minimum value Di_min for the narrowest through-groove 41A and the minimum value Do_min for the widest through-groove 41B are substantially the same, and the maximum value Di_max for the widest through-groove 41B and the maximum value Do_max for the narrowest through-groove 41A may be substantially the same.

By the way, the groove width of the through groove 41 may be different on both sides of the circumferential narrow groove 24 in the tire width direction. That is, as shown in FIG. 9, the through groove 41B has a constant groove width, and the groove width is the same between the vehicle width direction inner side and the vehicle width direction outer side of the circumferential narrow groove 24 . On the other hand, the groove widths of the through grooves 41C and 41D change in the middle of the extending direction, and the widths of the circumferential narrow grooves 24 differ between the vehicle width direction inner side and the vehicle width direction outer side. As shown in FIG. 9, the width of the through groove 41C is narrower on the outer side in the vehicle width direction than on the inner side in the vehicle width direction. As shown in FIG. 9, the width of the through groove 41D is wider on the outer side in the vehicle width direction than on the inner side in the vehicle width direction. On the outer side of the circumferential narrow groove 24 in the vehicle width direction, the groove width Wg_min of the narrowest through groove 41C and the groove width Wg_max of the widest through groove 41B are 1.50≦Wg_max/Wg_min≦3.00. meet. Further, on the inner side of the circumferential narrow groove 24 in the vehicle width direction, the groove width Wg_min of the narrowest through groove 41D and the groove width Wg_max of the widest through groove 41B satisfy 1.50≦Wg_max/Wg_min≦3.00. meet the conditions. At least one side of the circumferential narrow groove 24 in the tire width direction should satisfy this condition. In FIG. 9, three or more types of through grooves 41B, 41C and 41D are arranged. In FIG. 9, the minimum value Di_min may be smaller than the minimum value Do_min, and the maximum value Di_max may be larger than the maximum value Do_max.

Further, when the groove width of the through groove 41 is different on both sides of the circumferential narrow groove 24 in the tire width direction, the groove width of the narrow through groove is less than 1.5 [mm], and the sipe It can be. FIG. 10 is a diagram showing an example in which the groove width changes in the middle of the extending direction of the through groove 41 and the narrow through groove is a sipe. As shown in FIG. 10, the through grooves 41E and the through grooves 41F have sipes 41S outside the circumferential narrow grooves 24 in the vehicle width direction. In FIG. 10, all the sipes 41S have the same length in the tire width direction. Therefore, in the through grooves 41E and 41F, the groove width of the circumferential narrow groove 24 on the vehicle width direction outer side is narrower than the groove width of the circumferential narrow groove 24 on the vehicle width direction inner side. On the inner side of the circumferential narrow groove 24 in the vehicle width direction, the groove width Wg_min of the narrowest through groove 41E and the groove width Wg_max of the widest through groove 41F satisfy the condition that 1.50≦Wg_max/Wg_min≦3.00. meet. In FIG. 10, the minimum value Di_min may be smaller than the minimum value Do_min (same as the maximum value Do_max), and the maximum value Di_max may be larger than the maximum value Do_max.

In FIG. 10, the groove width (not shown) of the sipe 41S may be different on the outer side of the circumferential narrow groove 24 in the vehicle width direction. As for the sipes 41S, the groove width Wg_min of the narrowest sipe 41S and the groove width Wg_max of the widest sipe 41S may satisfy the condition of 1.50≦Wg_max/Wg_min≦20.0.

Regarding the through groove 41 , both the vehicle width direction inner side and the vehicle width direction outer side of the circumferential narrow groove 24 may be sipes. FIGS. 11 to 13 are diagrams showing a case where both the vehicle width direction inner side and the vehicle width direction outer side of the circumferential narrow groove 24 are sipes. 11 to 13, the through grooves 41 of the circumferential narrow grooves 24 are all sipes.

In FIG. 11, the groove width of the sipe 41S of the through groove 41G and the groove width of the sipe 41S of the through groove 41H are different, and the width of the through groove 41H is the narrowest on the inner side or the outer side of the circumferential narrow groove 24 in the vehicle width direction. A groove width Wg_min (not shown) of the groove 41G and a groove width Wg_max (not shown) of the widest through groove 41G satisfy the condition of 1.50≦Wg_max/Wg_min≦20.0. In FIG. 11, through grooves 41G and 41H having two types of groove widths are alternately arranged in the tire circumferential direction. This means that each of the plurality of through grooves 41 has a groove width narrower than that of the other through grooves 41 adjacent in the tire circumferential direction. This also means that each of the plurality of through grooves 41 has a groove width wider than that of the other through grooves 41 adjacent in the tire circumferential direction. In FIG. 11, the minimum value Do_min (same as the maximum value Do_max) and the minimum value Di_min (same as the maximum value Di_max) may be the same.

In FIG. 12, the groove width of the sipe 41S of the through groove 41G and the groove width of the sipe 41S of the through groove 41I are different, and the width of the narrowest through groove 24 is the inner side or the outer side of the circumferential narrow groove 24 in the vehicle width direction. A groove width Wg_min (not shown) of the groove 41G and a groove width Wg_max (not shown) of the widest through groove 41I satisfy the condition of 1.50≦Wg_max/Wg_min≦20.0. In FIG. 12, through grooves 41G and 41I having two types of groove widths are alternately arranged in the tire circumferential direction. This means that each of the plurality of through grooves 41 has a groove width narrower than that of the other through grooves 41 adjacent in the tire circumferential direction. This also means that each of the plurality of through grooves 41 has a groove width wider than that of the other through grooves 41 adjacent in the tire circumferential direction. In FIG. 12, the minimum value Di_min (the same as the maximum value Di_max) and the minimum value Do_min may be the same, and the maximum value Do_max may be greater than the maximum value Di_max.

In FIG. 13, the groove width of the sipe 41S of the through groove 41G is different from the groove width of the sipe 41S of the through groove 41I, and the width of the narrowest through groove 24 is the inner side or the outer side of the circumferential narrow groove 24 in the vehicle width direction. A groove width Wg_min (not shown) of the groove 41G and a groove width Wg_max (not shown) of the widest through groove 4IG satisfy the condition of 1.50≦Wg_max/Wg_min≦20.0. In FIG. 13, through grooves 41G and 41I having two types of groove widths are alternately arranged in the tire circumferential direction. This means that each of the plurality of through grooves 41 has a groove width narrower than that of the other through grooves 41 adjacent in the tire circumferential direction. This also means that each of the plurality of through grooves 41 has a groove width wider than that of the other through grooves 41 adjacent in the tire circumferential direction. In FIG. 13, the minimum value Di_min (the same as the maximum value Di_max) and the minimum value Do_min may be the same, and the maximum value Do_max may be greater than the maximum value Di_max.

[effect]
As described above, the pneumatic tire 10 includes the circumferential narrow grooves 24 extending in the tire circumferential direction, and the circumferential narrow grooves 24 extending in the tire width direction and extending in the tire width direction. In at least one side region in the tire width direction of the circumferential narrow groove 24, the width Wg_min of the narrowest through groove among the plurality of through grooves 41 and the width Wg_min of the widest through groove The groove width Wg_max of the groove has a relationship of 1.50≦Wg_max/Wg_min≦20.0. In addition, in at least one side region of the circumferential narrow groove 24 in the tire width direction, the groove width of the plurality of through grooves 41 is 1.5 [mm] or more, and among the plurality of through grooves 41, the width is the widest. The groove width Wg_min of the narrow through groove and the groove width Wg_max of the widest through groove have a relationship of 1.50≦Wg_max/Wg_min≦3.00.

Circumferential main grooves 23 arranged in one region bounded by the tire equatorial plane CL (outer region in the vehicle width direction in FIG. 2); It has a groove 24, and a shoulder land portion 35 and a second land portion 34 defined by the circumferential main groove 23 and the circumferential narrow groove 24 (see FIG. 2). The pneumatic tire 10 extends in the tire width direction and penetrates the circumferential narrow groove 24 , has an inner terminal portion in the tire width direction within the second land portion 34 , and has an outer terminal portion within the shoulder land portion 35 . is provided with a plurality of through grooves 41 (see FIG. 3). Further, the groove width Wg_min of the narrowest through groove and the groove width Wg_max of the widest through groove have a relationship of 1.50≦Wg_max/Wg_min≦20.0. When the groove widths of the plurality of through grooves are 1.5 mm or more, there is a relationship of 1.50≦Wg_max/Wg_min≦3.00.

In such a configuration, (1) the through grooves 41 penetrate the circumferential narrow grooves 24, thereby improving the drainage performance in the vicinity of the circumferential narrow grooves 24 and improving the wet performance of the tire. At the same time, since the through groove 41 does not open to the circumferential main groove 23 and the tire ground contact edge T, the rigidity of the left and right land portions 34 and 35 defined by the circumferential narrow groove 24 is ensured. As a result, there is an advantage that wet performance and dry performance of the tire are efficiently compatible. (2) Since the plurality of types of through grooves 41 (41A to 41I) having different groove widths are arranged at predetermined intervals in the tire circumferential direction, the plurality of types of through grooves 41 all have the same groove width and the same length. A through-groove with a wide groove width is arranged on the tread surface of one land portion (land portions 34 and 35 in FIG. 3) as compared with a configuration having a large width (not shown). As a result, there is an advantage that the dry performance and wet performance of the tire can be improved in a well-balanced manner.

Further, in the pneumatic tire 10, the tire width direction length L1_min of the shortest through groove among the plurality of through grooves 41 and the tire width direction length L1_max of the longest through groove are 1.10≦1.10. There is a relationship of L1_max/L1_min≦3.00, and the width Wg1 of the shortest through groove and the width Wg2 of the longest through groove have a relationship of Wg2>Wg1. As a result, the positions of the inner end portions of the through grooves 41A and 41B in the second land portion 34 are optimized, and there is an advantage that the dry performance and wet performance of the tire are compatible.

Moreover, in the pneumatic tire 10, the pair of through grooves 41A and 41B having different groove widths are preferably arranged alternately in the tire circumferential direction (see FIGS. 3 and 4). Thereby, each of the plurality of through grooves 41 has a groove width narrower than the groove width of the other through grooves adjacent in the tire circumferential direction. Further, each of the plurality of through grooves has a groove width wider than that of the other through grooves adjacent in the tire circumferential direction. As a result, the dry performance and wet performance of the tire can be improved in a well-balanced manner.

In addition, in the pneumatic tire 10, the shoulder land portion 35 has one terminal end inside the shoulder land portion 35 and is provided with a shoulder lug groove 42 extending in the tire width direction and opening at the tire ground contact edge T ( See Figure 2). Further, the through groove 41 (long through groove 41B in FIG. 2) is on an extension line of the groove center line of the shoulder lug groove 42 . Thereby, there is an advantage that the drainage performance of the shoulder land portion 35 is improved.

Further, in the pneumatic tire 10, the inclination angle θ of the through groove 41 with respect to the tire circumferential direction is preferably in the range of 50[deg]≦θ≦80[deg]. As a result, the dry performance and wet performance of the tire can be improved in a well-balanced manner.

Further, in the pneumatic tire 10, the ratio of the groove width of each of the plurality of through grooves 41 to the groove width of the circumferential narrow grooves 24 is preferably 0.30 or more and 1.30 or less. As a result, the dry performance and wet performance of the tire can be improved in a well-balanced manner.

In addition, in the pneumatic tire 10, the shoulder land portion 35 has one terminal end inside the shoulder land portion 35 and is provided with a shoulder lug groove 42 extending in the tire width direction and opening at the tire ground contact edge T ( See Figure 2). Further, the groove center line of the through groove 41 does not overlap the groove center line of the shoulder lug groove 42 in the tire circumferential direction. As a result, there is an advantage that the pattern noise caused by the overlapping of the through grooves is reduced and the quietness (noise performance) of the tire is improved.

Further, in the pneumatic tire 10, the distance D2 in the tire width direction from the end portion of the shoulder lug groove 42 to the outer end portion of the through groove 41 facing the shoulder lug groove 42, and the contact width W2 of the shoulder land portion 35 has a relationship of 0.10≤D2/W2≤0.60 (see FIG. 3). As a result, there is an advantage that the dry performance and wet performance of the tire are compatible. That is, the above lower limit ensures the rigidity and ground contact area of the shoulder land portion 35, thereby ensuring the dry performance of the tire. Moreover, the above upper limit ensures that the through grooves 41 and the shoulder lug grooves 42 extend in the tire width direction, thereby ensuring the wet performance of the tire.

Further, in the pneumatic tire 10, the arrangement interval P1 of the through grooves 41 and the arrangement interval P2 of the shoulder lug grooves 42 in the tire circumferential direction have a relationship of 0.30≦P1/P2≦0.70. Accordingly, there is an advantage that the arrangement intervals P1 and P2 of the through grooves 41 and the shoulder lug grooves 42 are optimized.

In addition, the pneumatic tire 10 is provided with a mounting direction indicator (not shown) for designating that one region (the outer region in the vehicle width direction in FIG. 2) should be mounted on the vehicle with the outer region in the vehicle width direction. By arranging the circumferential narrow grooves and the through grooves in the vehicle width direction outer region, dry performance, wet performance, and noise performance can be improved in a well-balanced manner.

14 to 16 are charts showing the results of performance tests of the pneumatic tire according to the embodiment of the invention.

In this performance test, multiple types of test tires were evaluated for (1) dry steering stability performance, (2) wet steering stability performance, and (3) noise performance. Also, a test tire with a tire size of 245/40R18 97Y was mounted on a rim with a rim size of 18×8.5J, and an internal pressure of 230 [kPa] and a JATMA specified load were applied to the test tire. Also, the test tires are mounted on all wheels of a passenger car, which is the test vehicle.

(1) In the evaluation of dry steering stability performance, the test vehicle runs on a dry road surface test course having a flat circuit at a speed of 60 [km/h] to 100 [km/h]. A test driver then conducts a sensory evaluation of steering performance during lane changes and cornering, as well as stability during straight-ahead driving. This evaluation is performed by index evaluation with the conventional example as a standard (100), and the larger the value, the better.

(2) In the evaluation of wet steering stability performance, a test vehicle is run on a predetermined test course under rainy weather conditions, and lap times are measured. Then, index evaluation is performed based on this measurement result. This evaluation is performed by index evaluation with the conventional example as a standard (100), and the larger the value, the better.

(3) In the noise performance evaluation, the test vehicle coasts on a test course with a rough road surface at a speed of 10 [km/h] to 20 [km/h], and the test driver performs a sensory evaluation of the vehicle interior noise. This evaluation is performed by index evaluation with the conventional example as a standard (100), and the larger the value, the better.

The test tires of Examples 1 to 29 had the configurations shown in FIGS. and a shoulder lug groove 42 are provided in the vehicle width direction outer region. Further, in the test tires of Examples 1 to 29, the groove width Wg_min of the narrowest through-groove and the groove width Wg_max of the widest through-groove among the plurality of through-grooves are 1.50≦ It has a relationship of Wg_max/Wg_min≦20.0. When the groove width of the through grooves 41A and 41B is 1.5 mm or more, the groove width Wg_min of the narrowest through groove and the groove width Wg_max of the widest through groove among the plurality of through grooves are 1.50. It has a relationship of ≦Wg_max/Wg_min≦3.00.

In the test tire of the conventional example, the groove width of the through groove is 5.0 [mm], and the groove width and length of the through groove are all equal. The conventional test tire did not have shoulder lug grooves 42 .

As shown in the test results, it can be seen that the test tires of Examples 1 to 29 are improved in wet steering stability performance, dry steering stability performance, and noise performance.

10 pneumatic tire; 11 bead core; 12 bead filler; 13 carcass layer; 14 belt layer; 15 tread rubber; 41, 41A to 41I through groove; 41S sipe; 42 shoulder lug groove; 141, 142 cross belt; 143 belt cover; CL tire equatorial plane;

Claims (13)

A circumferential groove extending in the tire circumferential direction, and a plurality of through grooves extending in the tire width direction, penetrating the circumferential groove, and having both ends terminated in land portions, wherein the circumferential groove In at least one region in the tire width direction, the width Wg_min of the narrowest through-groove and the width Wg_max of the widest through-groove among the plurality of through-grooves are 1.50≦Wg_max/Wg_min. A pneumatic tire having a relationship ≦20.0. In at least one side region of the circumferential groove in the tire width direction, the groove width of the plurality of through grooves is 1.5 mm or more, and among the plurality of through grooves, the narrowest through groove The pneumatic tire according to claim 1, wherein the groove width Wg_min and the groove width Wg_max of the widest through groove have a relationship of 1.50≤Wg_max/Wg_min≤3.00. Among the plurality of through grooves, the tire width direction length L1_min of the shortest through groove and the tire width direction length L1_max of the longest through groove have a relationship of 1.10≦L1_max/L1_min≦3.00. 3. The pneumatic tire according to claim 1, wherein the width Wg1 of the shortest through groove and the width Wg2 of the longest through groove have a relationship of Wg2>Wg1. The pneumatic tire according to any one of claims 1 to 3, wherein the pair of through grooves having groove widths different from each other are arranged alternately in the tire circumferential direction. The pneumatic tire according to claim 4, wherein each of the plurality of through-grooves has a groove width narrower than that of other through-grooves adjacent in the tire circumferential direction. The pneumatic tire according to claim 4, wherein each of the plurality of through grooves has a groove width wider than that of other through grooves adjacent in the tire circumferential direction. The pneumatic tire according to any one of claims 1 to 6, wherein an inclination angle θ of the through groove with respect to the tire circumferential direction is in a range of 50 [deg] ≤ θ ≤ 80 [deg]. The pneumatic tire according to any one of claims 1 to 7, wherein the ratio of the groove width of each of the plurality of through grooves to the groove width of the circumferential groove is 0.30 or more and 1.30 or less. . The shoulder land portion defined by the circumferential groove includes a shoulder lug groove having one terminal end within the shoulder land portion and extending in the tire width direction to open at the tire ground contact edge, and
The pneumatic tire according to any one of claims 1 to 8, wherein the through groove is on an extension line of the groove center line of the shoulder lug groove. The shoulder land portion defined by the circumferential groove includes a shoulder lug groove having one terminal end within the shoulder land portion and extending in the tire width direction to open at the tire ground contact edge, and
The pneumatic tire according to any one of claims 1 to 9, wherein the groove centerline of the through groove does not overlap the groove centerline of the shoulder lug groove in the tire circumferential direction. A distance D2 in the tire width direction from the end portion of the shoulder lug groove to an outer end portion of the through groove facing the shoulder lug groove and a contact width W2 of the shoulder land portion are 0.10≦D2/ 11. The pneumatic tire according to claim 9 or 10, having a relationship of W2≦0.60. 12. Any one of claims 9 to 11, wherein an arrangement interval P1 of the through grooves and an arrangement interval P2 of the shoulder lug grooves in the tire circumferential direction have a relationship of 0.30≤P1/P2≤0.70. The pneumatic tire described in . The pneumatic tire according to any one of claims 1 to 12, further comprising a mounting direction indicator for designating that the one-side region should be mounted on the vehicle with the region on the outside in the vehicle width direction.

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