JP6996401B2 - tire - Google Patents

Description

The present invention relates to a tire capable of achieving both steering stability performance and wet performance.

Conventionally, a tire having a plurality of main grooves extending in the tire circumferential direction is known. This type of tire is required to have both steering stability performance and wet performance. For example, the tire of Patent Document 1 below has a tread portion in which the direction of mounting on the vehicle is specified, and by increasing the rigidity of the outside of the vehicle, both steering stability performance and wet performance are achieved.

Japanese Unexamined Patent Publication No. 2009-67244

However, the demand for tires has been increasing year by year, and further improvement has been required for the tires of Patent Document 1.

The present invention has been devised in view of the above circumstances, and a main object of the present invention is to provide a tire capable of achieving both steering stability performance and wet performance at a high level.

The present invention is a tire having a tread portion whose mounting direction on a vehicle is specified.
The tread portion has a plurality of main grooves extending in the tire circumferential direction and a plurality of land portions classified by the plurality of main grooves.
The plurality of main grooves include an outer crown main groove and an outer shoulder main groove located outside the vehicle with respect to the outer crown main groove when mounted on a vehicle.
The plurality of land portions are an outer middle land portion divided between the outer crown main groove and the outer shoulder main groove, and an outer shoulder land divided between the outer shoulder main groove and the outer tread end. Including the part
In the outer shoulder land portion, a circumferential narrow groove extending in the tire circumferential direction, an outer shoulder lateral groove extending from the outer tread end and communicating with the circumferential fine groove, and terminating in the outer shoulder land portion, and the outer side. An outer shoulder sipe extending from the tread end to the outer shoulder main groove is provided.
In the outer middle land portion, one end communicates with the outer shoulder main groove and the other end communicates with the outer middle land portion and the other end communicates with the outer middle land portion, and one end communicates with the outer crown main groove and the other end thereof. It includes an outer middle sipe that terminates within the outer middle land.

In the tire according to the present invention, the outer shoulder lateral groove and the outer shoulder sipe are preferably arranged alternately in the tire circumferential direction.

In the tire according to the present invention, the outer middle short groove and the outer middle sipe are preferably arranged alternately in the tire circumferential direction.

In the tire according to the present invention, the outer middle short groove and the outer middle sipe overlap in the tire axial direction, and the overlapping width in the tire axial direction is 10 to 10 to the land width in the tire axial direction of the outer middle land portion. It is preferably 30%.

In the tire according to the present invention, the plurality of main grooves are the inner crown main groove located inside the vehicle from the outer crown main groove and the inner side located inside the vehicle than the inner crown main groove when mounted on the vehicle. Including the shoulder main groove
The plurality of land portions are a crown land portion divided between the outer crown main groove and the inner crown main groove, and an inner middle land divided between the inner crown main groove and the inner shoulder main groove. Including the portion and the inner shoulder land portion partitioned between the inner shoulder main groove and the inner tread end.
The crown land portion has a first crown sipe having one end communicating with the outer crown main groove and the other end communicating within the crown land portion, and one end communicating with the inner crown main groove and the other end having the crown. A second crown sipe that terminates in the land is provided,
It is preferable that the first crown sipe and the second crown sipe are inclined in the same direction with respect to the tire axial direction.

In the tire according to the present invention, the angle θ1 of the first crown sipe with respect to the tire axial direction is preferably smaller than the angle θ2 of the second crown sipe with respect to the tire axial direction.

In the tire according to the present invention, the length L1 of the first crown sipe in the tire axial direction is preferably larger than the length L2 of the second crown sipe in the tire axial direction.

In the tire according to the present invention, the land portion of the crown is provided with a shallow crown groove extending from the outer crown main groove to the inner crown main groove and having a depth of less than 2 mm, and the bottom of the shallow crown groove. , The first crown sipe and the second crown sipe are preferably provided.

In the present specification, the sipe is a notch in which at least a part of the wall surface of the sipe can come into contact with each other at the time of touchdown, and the width is preferably less than 1.5 mm.

The present invention has focused on the outer shoulder land portion and the outer middle land portion, which have a large influence on the steering stability performance.

In the outer shoulder land, the outer shoulder lateral groove extending from the outer tread end terminates within the outer shoulder land. Therefore, the rigidity of the outer shoulder land portion is increased, and the steering stability performance can be improved. Further, each outer shoulder lateral groove communicates with the circumferential narrow groove, and the outer shoulder sipe extending from the outer tread end communicates with the outer shoulder main groove. This makes it possible to compensate for the decrease in drainage property caused by the termination of the outer shoulder lateral groove in the land portion of the outer shoulder, and to exhibit excellent wet performance.

Moreover, since the outer shoulder sipe crosses the outer shoulder land, torsional rigidity is appropriately generated when an input is applied to the outer shoulder land. This can contribute to the improvement of the initial responsiveness in particular.

Also in the outer middle land area, the outer middle short groove extending from the outer shoulder main groove and the outer middle sipe extending from the outer crown main groove are terminated in the outer middle land area, respectively. Therefore, the rigidity of the outer middle land portion can be increased while ensuring the wet performance. As a result, in cooperation with the above-mentioned outer shoulder land area, it becomes possible to achieve both steering stability performance and wet performance at a high level.

It is a development view of the tread part of the tire of one Embodiment of this invention. It is an enlarged view of the outer shoulder land part. It is an enlarged view of the outer middle land part. It is an enlarged view of the land part of the crown. It is an enlarged view of the inner middle land part and the inner shoulder land part. It is sectional drawing of the main groove.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a developed view of a tread portion 2 of a tire 1 showing an embodiment of the present invention. The tire 1 of the present embodiment can be used for various tires such as pneumatic tires for passenger cars and heavy loads, and non-pneumatic tires in which pressurized air is not filled inside the tires. The tire 1 of the present embodiment is particularly preferably used as a pneumatic tire for a passenger car.

As shown in FIG. 1, the tire 1 of the present embodiment has a tread portion 2 having a designated orientation for mounting on a vehicle. The tread portion 2 has an outer tread end To located on the outer side of the vehicle and an inner tread end Ti located on the inner side of the vehicle when the tire 1 is mounted on the vehicle. The direction of mounting on the vehicle is indicated by characters or symbols on the sidewall portion (not shown), for example.

In the case of a pneumatic tire, each tread end To and Ti are the most outer contact positions in the tire axial direction when a normal load is applied to the tire 1 in a normal state and the tire 1 touches a flat surface at a camber angle of 0 °. Here, the "normal state" is a no-load state in which the tire 1 is rim-assembled on the normal rim and adjusted to the normal internal pressure. Hereinafter, unless otherwise specified, the dimensions and the like of each part of the tire 1 are values measured in this normal state.

A "regular rim" is a rim defined for each tire in the standard system including the standard on which the tire is based. For example, "standard rim" for JATMA, "Design Rim" for TRA, and ETRTO. If there is, it is "Measuring Rim".

"Regular internal pressure" is the air pressure defined for each tire in the standard system including the standard on which the tire is based. For JATTA, "maximum air pressure", for TRA, the table "TIRE LOAD LIMITS AT" The maximum value described in "VARIOUS COLD INFLATION PRESSURES", or "INFLATION PRESSURE" for ETRTO.

"Regular load" is the load defined for each tire in the standard system including the standard on which the tire is based. "Maximum load capacity" for JATTA and "TIRE LOAD LIMITS" for TRA. The maximum value described in "AT VARIOUS COLD INFLATION PRESSURES", or "LOAD CAPACITY" for ETRTO.

The tread portion 2 of the present embodiment has a plurality of main grooves 3 extending in the tire circumferential direction and a plurality of land portions 4 divided by the plurality of main grooves 3. Each of the plurality of main grooves 3 has a groove width W1 to W4 of 2% or more of the tread width Tw. Here, the tread width Tw is the distance in the tire axial direction from the outer tread end To to the inner tread end Ti in the normal state.

The plurality of main grooves 3 of the present embodiment include an outer crown main groove 5 and an outer shoulder main groove 6 located outside the vehicle from the outer crown main groove 5 when mounted on the vehicle. The outer crown main groove 5 extends continuously and linearly in the tire circumferential direction, for example, between the tire equator C and the outer tread end To. The outer shoulder main groove 6 extends continuously and linearly in the tire circumferential direction between the outer crown main groove 5 and the outer tread end To.

The plurality of main grooves 3 of the present embodiment include an inner crown main groove 7 located inside the vehicle from the outer crown main groove 5 and an inner shoulder located inside the vehicle than the inner crown main groove 7 when mounted on the vehicle. Further includes the main groove 8. The inner crown main groove 7 extends continuously and linearly in the tire circumferential direction, for example, between the tire equator C and the inner tread end Ti. The inner shoulder main groove 8 extends continuously and linearly between the inner crown main groove 7 and the inner tread end Ti in the tire circumferential direction.

The outer tread region, which is outside the tire equator C when mounted on a vehicle, is a region in which a large load is applied when turning or changing lanes, and has a large effect on steering stability performance. Therefore, from the viewpoint of improving steering stability performance, it is effective to increase the land ratio to increase the rigidity in the outer tread region. Further, in order to secure the wet performance of the tire as a whole, it is effective to reduce the land ratio and improve the drainage property in the inner tread region inside the tire equator C.

From this point of view, the groove width W2 of the outer shoulder main groove 6 is smaller than the groove width W1 of the outer crown main groove 5, the groove width W3 of the inner crown main groove 7, and the groove width W4 of the inner shoulder main groove 8. Is desirable. Further, since it is more difficult to drain water on the tire equator C side than on the tread end To and Ti sides, the groove width W1 of the outer crown main groove 5 and the groove width W3 of the inner crown main groove 7 are the grooves of the inner shoulder main groove 8. It is desirable that the width is larger than W4. Further, the total of the groove widths W1 to W4 (W1 + W2 + W3 + W4) is preferably in the range of 22% to 28% of the tread width Tw from the viewpoint of the balance between steering stability and wet performance.

FIG. 6 shows a groove cross section orthogonal to the groove length direction of the main groove 3. As shown in FIG. 6, each main groove 3 includes an outer groove wall surface 3wo and an inner groove wall surface 3wi, respectively. In each main groove 3, the angle αo of the outer groove wall surface 3wo with respect to the normal of the tread tread 2S is set to be larger than the angle αi of the inner groove wall surface 3wi with respect to the normal of the tread tread 2S. As a result, the lateral rigidity against the lateral force acting on the vehicle when turning or changing lanes can be increased as compared with the case where the angles of the groove wall surfaces 3wi and 3wo are equal to each other at (αo + αi) / 2. can. That is, it is possible to improve steering stability while keeping the groove volume the same. The angle αo is preferably in the range of 10 to 12 °, and the angle αi is preferably in the range of 8 to 10 °. The angle difference (αo-αi) is preferably 2 ° or more. The groove depth of each main groove 3 can be appropriately adopted according to the custom.

As shown in FIG. 1, the plurality of land portions 4 are the outer middle land portion 10 divided between the outer crown main groove 5 and the outer shoulder main groove 6, and the outer shoulder main groove 6 and the outer tread end To. Includes the outer shoulder tread 11 partitioned between and. The plurality of land portions 4 are further divided between the crown land portion 12 divided between the outer crown main groove 5 and the inner crown main groove 7, and between the inner crown main groove 7 and the inner shoulder main groove 8. It includes an inner middle land portion 13 and an inner shoulder land portion 14 partitioned between the inner shoulder main groove 8 and the inner tread end Ti.

FIG. 2 is an enlarged view of the outer shoulder land portion 11. As shown in FIG. 2, the outer shoulder land portion 11 of the present embodiment is provided with one circumferential fine groove 15, a plurality of outer shoulder lateral grooves 16, and a plurality of outer shoulder sipes 17. ..

The circumferential narrow groove 15 extends in the tire circumferential direction between the outer shoulder main groove 6 and the outer tread end To. The circumferential narrow groove 15 is a groove wider than the outer shoulder sipe 17 and narrower than the main groove 3 and the outer shoulder lateral groove 16. The lower limit of the groove width W ₁₅ of the circumferential fine groove 15 is preferably 1.5 mm or more, and the upper limit is preferably 3 mm or less.

If the circumferential narrow groove 15 is too far from the outer shoulder main groove 6, the drainage property of the outer shoulder land portion 11 is adversely affected, and if it is too close, the rigidity of the outer shoulder land portion 11 is adversely affected. Therefore, the distance K15 in the tire axial direction between the circumferential narrow groove ₁₅ and the outer shoulder main groove 6 is preferably 15 to 30% of the land width K11 of the outer shoulder ₁₁ .

The outer shoulder lateral groove 16 extends from the outer tread end To toward the inside of the vehicle, communicates with the circumferential narrow groove 15, and terminates in the outer shoulder land portion 11. Further, the outer shoulder sipe 17 extends from the outer tread end To beyond the circumferential narrow groove 15 to the outer shoulder main groove 6.

As described above, in the outer shoulder lateral groove 16, since the tip portion 16e is terminated in the outer shoulder land portion 11, the rigidity of the outer shoulder land portion 11 can be maintained high.

Further, when the outer shoulder horizontal groove 16 communicates with the circumferential fine groove 15, an excellent drainage effect is exhibited. Further, when the outer shoulder sipe 17 crosses the outer shoulder land portion 11, a high wiping effect and an edge effect on the water film on the road surface are exhibited. The interaction between the drainage effect, the wiping effect, and the edge effect compensates for the decrease in drainage property caused by the termination of the tip portion 16e of the outer shoulder lateral groove 16 in the outer shoulder land portion 11, and provides excellent wet performance. It will be possible to demonstrate. Further, when a force is applied to the outer shoulder land portion 11 from the road surface, the outer shoulder sipe 17 appropriately generates torsional rigidity, which can contribute to the improvement of the initial response in particular.

In the present embodiment, the case where the tip portion 16e of the outer shoulder lateral groove 16 protrudes from the circumferential narrow groove 15 is shown. In this case, the protrusion amount δ is preferably 50% or less, more preferably ₃₀ % or less of the distance K15. The tip portion 16e may be terminated without protruding from the circumferential narrow groove 15.

The outer shoulder lateral groove 16 and the outer shoulder sipe 17 are preferably arranged alternately in the tire circumferential direction. Further, the outer shoulder lateral groove 16 and the outer shoulder sipe 17 are preferably inclined in the same direction with respect to the tire axial direction, and more preferably arranged substantially parallel to each other. The angle θ ₁₆ of the outer shoulder lateral groove 16 with respect to the tire axial direction and the angle θ ₁₇ of the outer shoulder sipe 17 with respect to the tire axial direction are preferably in the range of 3 to 20 °, respectively. "Approximately parallel" includes those that are parallel and those that are tilted at an angle within ± 5 ° with respect to the parallel.

FIG. 3 is an enlarged view of the outer middle land portion 10. As shown in FIG. 3, the outer middle land portion 10 of the present embodiment is provided with a plurality of outer middle short grooves 18 and a plurality of outer middle sipes 19.

The outer middle short groove 18 communicates with the outer shoulder main groove 6 at one end and terminates at the other end within the outer middle land portion 10. The outer middle sipe 19 communicates with the outer crown main groove 5 at one end and terminates at the other end within the outer middle land portion 10.

Such an outer middle short groove 18 and an outer middle sipe 19 can maintain high rigidity of the outer middle land portion 10 and contribute to improvement of steering stability. Further, the wet performance can be exhibited by the drainage effect of the outer middle short groove 18 and the wiping effect and the edge effect of the outer middle sipe 19. Since the outer middle short groove 18 is communicated with the outer shoulder main groove 6 having a small groove width W2, the wet performance can be exhibited in a well-balanced manner over the entire outer tread region.

The outer middle short groove 18 and the outer middle sipe 19 are preferably arranged alternately in the tire circumferential direction. Further, the outer middle short groove 18 and the outer middle sipe 19 are preferably inclined in the same direction with respect to the tire axial direction, and more preferably arranged substantially parallel to each other. The angle θ ₁₈ of the outer middle short groove 18 with respect to the tire axial direction and the angle θ ₁₉ of the outer middle sipe 19 with respect to the tire axial direction are preferably larger than the angles θ ₁₆ and θ ₁₇ , respectively, and are particularly 15 to 15. A range of 30 ° is more preferred. "Approximately parallel" includes those that are parallel and those that are tilted at an angle within ± 5 ° with respect to the parallel.

The tire axial length L ₁₈ of the outer middle short groove 18 is preferably 40 to 70% of the land width K ₁₀ of the outer middle land portion 10. If the length L ₁₈ is less than 40% of the land width K ₁₀ , the wet performance tends to be insufficient, and conversely, if it exceeds 70%, the rigidity of the outer middle land 10 tends to be insufficient. From the viewpoint of wet performance, the outer middle short groove 18 and the outer middle sipe 19 are preferably overlapped in the tire axial direction, and the overlapping width Ka is more preferably ₁₀ to 30% of the land width K10.

FIG. 4 is an enlarged view of the land portion 12 of the crown. As shown in FIG. 4, the crown land portion 12 of the present embodiment is provided with a plurality of first crown sipes 21 and a plurality of second crown sipes 22. One end of the first crown sipe 21 communicates with the outer crown main groove 5, and the other end ends within the crown land portion 12. One end of the second crown sipe 22 communicates with the inner crown main groove 7, and the other end ends within the crown land portion 12. The first crown sipe 21 and the second crown sipe 22 are alternately arranged in the tire circumferential direction.

Such a first crown sipe 21 and a second crown sipe 22 can maintain high rigidity of the crown land portion 12 and contribute to improvement of steering stability. In addition, wet performance can be exhibited by the wiping effect and the edge effect.

The first crown sipe 21 and the second crown sipe 22 are inclined in the same direction with respect to the tire axial direction. In particular, the angle θ1 of the first crown sipe 21 with respect to the tire axial direction is preferably smaller than the angle θ2 of the second crown sipe with respect to the tire axial direction. As a result, the wiping effect and edge effect of the first crown sipe 21 are relatively higher than the wiping effect and edge effect of the second crown sipe 22, and the outer tread region having a high land ratio and the inner tread region having a low land ratio are obtained. We are trying to balance the wet performance in. The angle θ1 is preferably in the range of 10 to 40 °, and the angle θ2 is preferably in the range of 30 to 45 °. The difference (θ2-θ1) is preferably 5 ° or more.

For the same purpose, it is preferable that the length L1 of the first crown sipe 21 in the tire axial direction is larger than the length L2 of the second crown sipe 22 in the tire axial direction. The length L1 is preferably in the range of 25% to 45% of the land width K ₁₂ of the crown land portion 12, and the length L2 is preferably in the range of 20% to 40% of the land width K ₁₂ of the crown land portion 12. ..

In the present embodiment, the first crown sipe 21 and the second crown sipe 22 are provided at the bottom of the crown shallow groove 23 having a depth of less than 2 mm. The crown shallow groove 23 extends from the outer crown main groove 5 to the inner crown main groove 7 along the first crown sipe 21 and the second crown sipe 22. Such a crown shallow groove 23 is useful for improving drainage while maintaining high rigidity of the crown land portion 12. The groove width of the crown shallow groove 23 is preferably 2 to 5 mm.

The crown shallow groove 23 can be removed. Further, the crown shallow groove 23 is formed only in the portion where the first crown sipe 21 and the second crown sipe 22 are arranged, and the crown shallow groove 23 is removed between the first crown sipe 21 and the second crown sipe 22. You can also do it. Conversely, the crown shallow groove 23 can be formed only between the first crown sipe 21 and the second crown sipe 22.

FIG. 5 is an enlarged view of the inner middle land portion 13 and the inner shoulder land portion 14. As shown in FIG. 5, a composite groove 26 composed of an inner middle short groove 24 and an inner middle sipe 25 is arranged in the inner middle land portion 13. One end of the inner middle short groove 24 communicates with the inner shoulder main groove 8 and the other end ends in the inner middle land portion 13. The inner middle sipe 25 extends from the other end of the inner middle short groove 24 to the inner crown main groove 7. The composite groove 26 can further exert the drainage effect, the wiping effect, and the edge effect as compared with the case where the inner middle short groove 24 and the inner middle sipe 25 are formed separately.

A second inner middle sipe 27 extending from the inner shoulder main groove 8 to the inner crown main groove 7 is further arranged on the inner middle land portion 13. The second inner middle sipe 27 and the composite groove 26 are alternately arranged in the tire circumferential direction. The composite groove 26 and the second inner middle sipe 27 are preferably inclined in the same direction with respect to the tire axial direction, and more preferably arranged substantially parallel to each other. "Approximately parallel" includes those that are parallel and those that are tilted at an angle within ± 5 ° with respect to the parallel.

The angle θ ₂₆ of the composite groove 26 with respect to the tire axial direction and the angle θ ₂₇ of the second inner middle sipe 27 with respect to the tire axial direction are preferably in the range of 30 to 45 °, respectively. In particular, it is more preferable that the difference from the angle θ2 is 5 ° or less.

The outer middle sipe 19, the first crown sipe 21, the second crown sipe 22, the composite groove 26, and the second inner middle sipe 27 are preferably inclined in the same direction with respect to the tire axial direction. In particular, in the present embodiment, the outer middle sipe 19, the first crown sipe 21, the second crown sipe 22, and the composite groove 26 are smoothly continuous via the main groove 3. Similarly, the outer middle sipe 19, the first crown sipe 21, the second crown sipe 22, and the second inner middle sipe 27 are smoothly continuous via the main groove 3. As a result, when a force acts on the tread portion 2 from the road surface, torsional rigidity is appropriately generated in the tread portion 2, and the initial responsiveness can be improved.

The inner shoulder land portion 14 is provided with a plurality of inner shoulder lateral grooves 28 extending from the inner tread end Ti to the inner shoulder main groove 8. The inner shoulder lateral groove 28 exhibits an excellent drainage effect by crossing the inner shoulder land portion 14. As a result, the wet performance in the inner tread region is relatively improved as compared with the outer tread region, and the wet performance of the tire as a whole is improved while exhibiting excellent steering stability.

In particular, in the present embodiment, the inner shoulder land portion 14 is provided with a plurality of inner shoulder sipes 29 extending from the inner tread end Ti to the inner shoulder main groove 8. The inner shoulder sipe 29 exhibits an excellent wiping effect and an edge effect by crossing the inner shoulder land portion 14, and the wet performance of the tire as a whole is further improved.

The inner shoulder lateral groove 28 and the inner shoulder sipe 29 are preferably arranged alternately in the tire circumferential direction. Further, the inner shoulder lateral groove 28 and the inner shoulder sipe 29 are preferably inclined in the same direction with respect to the tire axial direction, and more preferably arranged substantially parallel to each other. The angle θ ₂₈ of the inner shoulder lateral groove 28 with respect to the tire axial direction and the angle θ ₂₉ of the inner shoulder sipe 29 with respect to the tire axial direction are preferably in the range of 3 to 20 °, respectively. "Approximately parallel" includes those that are parallel and those that are tilted at an angle within ± 5 ° with respect to the parallel.

Although the particularly preferred embodiment of the present invention has been described in detail above, the present invention is not limited to the above-described embodiment and can be modified into various embodiments.

A tire having the basic pattern shown in FIG. 1 was prototyped based on the specifications shown in Table 1. The steering stability and wet performance of each test tire were tested. The common specifications and test methods for each test tire are as follows.

Tire size: 205 / 55R16
Rim size: 16 x 6.5JJ
Air pressure: 230 kPa
Test vehicle: Front-wheel drive vehicle, displacement 2000cc
Tire mounting position: All wheels

<Maneuvering stability performance>
The steering stability of the test vehicle when traveling on a dry road surface was evaluated by the driver's sensuality. The result is represented by an index with Comparative Example 1 as 100, and the larger the value, the better the steering stability performance.

<Wet performance>
(1) Hydro performance:
The above test vehicle travels on an asphalt road surface with a depth of 5 mm and a length of 20 m and a radius of 100 m, the lateral acceleration (lateral G) of the front wheels is measured, and the average lateral G at a speed of 50 to 80 km / h is obtained. Was done. The result is represented by an index with the value of Comparative Example 1 as 100, and the larger the value, the better the wet performance.
(2) Wet grip performance:
The test vehicle traveled on a wet road surface (sprinkled asphalt road surface), and the braking distance from an initial speed of 40 km / h was measured. The result is represented by an index with Comparative Example 1 as 100, and the larger the value, the shorter the braking distance and the better the wet performance.

As a result of the test, it was confirmed that the tires of the examples had both steering stability performance and wet performance (hydro performance and wet grip performance) in a high-dimensional and well-balanced manner as compared with the comparative example.

1 Tire 2S Tread tread 2 Tread part 3wi Groove wall surface 3wo Groove wall surface 3 Main groove 4 Land part 5 Outer crown main groove 6 Outer shoulder main groove 7 Inner crown main groove 8 Inner shoulder main groove 10 Outer middle land part 11 Outer shoulder land part 12 Crown land 13 Inner middle land 14 Inner shoulder land 15 Circumferential narrow groove 16 Outer shoulder lateral groove 17 Outer shoulder sipe 18 Outer middle short groove 19 Outer middle sipe 21 First crown sipe 22 Second crown sipe 23 Crown shallow groove 24 Inner middle short groove 25 Inner middle sipe 27 Inner middle sipe 28 Inner shoulder lateral groove

Claims (8)

A tire with a tread that is oriented to be mounted on a vehicle.
The tread portion has a plurality of main grooves extending in the tire circumferential direction and a plurality of land portions classified by the plurality of main grooves.
The plurality of main grooves include an outer crown main groove and an outer shoulder main groove located outside the vehicle with respect to the outer crown main groove when mounted on a vehicle.
The plurality of land portions are an outer middle land portion divided between the outer crown main groove and the outer shoulder main groove, and an outer shoulder land divided between the outer shoulder main groove and the outer tread end. Including the part
In the outer shoulder land portion, a circumferential narrow groove extending in the tire circumferential direction, an outer shoulder lateral groove extending from the outer tread end and communicating with the circumferential fine groove, and terminating in the outer shoulder land portion, and the outer side. An outer shoulder sipe extending from the tread end to the outer shoulder main groove is provided.
The outer middle land portion has an outer middle short groove having one end communicating with the outer shoulder main groove and the other end communicating with the outer middle land portion and one end communicating with the outer crown main groove and having the other end. A tire with an outer middle sipe that terminates within the outer middle land. The tire according to claim 1, wherein the outer shoulder lateral groove and the outer shoulder sipe are alternately arranged in the tire circumferential direction. The tire according to claim 1 or 2, wherein the outer middle short groove and the outer middle sipe are alternately arranged in the tire circumferential direction. The outer middle short groove and the outer middle sipe overlap in the tire axial direction, and the overlapping width in the tire axial direction is 10 to 30% of the land width in the tire axial direction of the outer middle land portion. The tire described in any of 3 to 3. The plurality of main grooves include an inner crown main groove located inside the vehicle from the outer crown main groove and an inner shoulder main groove located inside the vehicle than the inner crown main groove when mounted on the vehicle.
The plurality of land portions are a crown land portion divided between the outer crown main groove and the inner crown main groove, and an inner middle land divided between the inner crown main groove and the inner shoulder main groove. Including the portion and the inner shoulder land portion partitioned between the inner shoulder main groove and the inner tread end.
The crown land portion has a first crown sipe having one end communicating with the outer crown main groove and the other end communicating within the crown land portion, and one end communicating with the inner crown main groove and the other end having the crown. A second crown sipe that terminates in the land is provided,
The tire according to any one of claims 1 to 4, wherein the first crown sipe and the second crown sipe are inclined in the same direction with respect to the tire axial direction. The tire according to claim 5, wherein the angle θ1 of the first crown sipe with respect to the tire axial direction is smaller than the angle θ2 of the second crown sipe with respect to the tire axial direction. The tire according to claim 5 or 6, wherein the length L1 of the first crown sipe in the tire axial direction is larger than the length L2 of the second crown sipe in the tire axial direction. The land portion of the crown is provided with a shallow crown groove extending from the outer crown main groove to the inner crown main groove and having a depth of less than 2 mm, and the bottom of the shallow crown groove is formed with the first crown sipe. The tire according to any one of claims 5 to 7, wherein the second crown sipe is provided.

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