JP6029957B2 - Pneumatic tire - Google Patents

Description

  The present invention relates to a pneumatic tire.

Conventionally, a pattern having a circumferential main groove and a width direction groove is known as a tread pattern that achieves both wet performance and on-snow performance of a tire (see, for example, Patent Documents 1 and 2).
According to such a tread pattern, while the drainage is improved by the circumferential main grooves and the width direction grooves having a large groove width, the snow traction performance and the snow braking performance are ensured by the edge effect of the block defined by these grooves. can do.

JP 2001-191740 A JP 2005-297695 A

  However, in the tire having the above tread pattern, in order to improve drainage performance, the groove width of the circumferential main groove is increased, and therefore the length of the block in the tire width direction is reduced and the edge is reduced. There was a problem that the component was shortened and the traction performance on snow was lowered. Furthermore, even when the width of the circumferential main groove or the width direction groove is increased, the drainage performance may not be sufficiently improved, and it has been found that there is still room for improvement.

  The present invention is intended to solve the above-described problems, and an object thereof is to provide a pneumatic tire that achieves both wet performance and on-snow performance of the tire.

The inventors have intensively studied to solve the above problems.
As a result, the inventors have found that it is important to suppress the turbulent flow in the water drainage process and improve the water flow in each groove.
That is, in order to improve drainage performance, the inventors have found that it is necessary to increase the groove width and groove depth of the circumferential main groove and the width direction groove. By reducing the height at the position connected to the other groove, it is possible to suppress the generation of turbulent flow that hinders the flow of water in the vicinity of the connection position, and to achieve the above-mentioned object advantageously. The present invention has been obtained and the present invention has been completed.

This invention is made | formed based on said knowledge, The summary structure is as follows.
The pneumatic tire of the present invention has at least one circumferential main groove extending continuously in the tread circumferential direction on the tread surface, and a plurality of tires extending inward in the tread width direction from the tread end and connected to the circumferential main groove. And a plurality of sub-grooves extending across the width direction groove,
A cross-sectional area of the connecting portion to the circumferential main groove at the inner end portion in the tread width direction of the width direction groove is A (mm ² ), and the end portion on the one side in the tread circumferential direction of the sub groove is connected to the width direction groove. When the cross-sectional area of the connecting portion is B (mm ² ), and the cross-sectional area of the connecting portion to the tread end of the tread width outer end of the widthwise groove is C (mm ² ), A <C, and B <C, meets, the ratio a / C is from 0 to 0.24 and the ratio B / C is from 0.07 to 0.60,
The widthwise groove has a bottom raised portion, and the groove depth of the widthwise groove is shallower than the groove depth of the circumferential main groove at the bottom raised portion, and the groove depth of the circumferential main groove at a portion not raised at the bottom. It is characterized by deepness .
Thereby, the wet performance of a tire and the performance on snow can be made compatible.
Here, the `` tread surface '' means that the tire is in contact with the road surface when the tire is assembled to the applicable rim, filled with the specified internal pressure, and rolled while applying a load corresponding to the maximum load capacity. It means the outer peripheral surface over the entire circumference of the tire. The “tread end” refers to the outermost position of the tread surface in the tread width direction.
Here, the “applicable rim” is a rim in which an industrial standard effective for the region where the tire is produced and used is determined for each tire, and is a standard for YEAR BOOK of JATMA (Japan Automobile Tire Association). Rim, “Design Rim” for YEAR BOOK of TRA (THE TIRE and RIM ASSOCIATION INC.), STANDARD MANUR for “ETERO (European Tire and Rim Technical Organization)” IM The “specified internal pressure” refers to the air pressure (maximum air pressure) corresponding to the maximum load of the tire specified according to the tire size in the above standards such as JATMA. Furthermore, the “maximum load capacity” refers to the maximum load capacity of a tire defined according to the tire size in the above standards such as JATMA.
In addition, the phrase “the circumferential main groove extends continuously in the tread circumferential direction” does not only mean that the circumferential main groove extends without tilting with respect to the tread circumferential direction, but also with respect to the tread circumferential direction. It also includes the case where it extends.
Further, the width direction groove “extends inward in the tread width direction and connects to the circumferential groove” does not only mean that the width direction groove extends inward in the tread width direction without being inclined in the tread width direction. Including the case where it is inclined relative to the direction and extends inward in the tread width direction.
The cross-sectional area A refers to the cross-sectional area of the tire circumferential cross-section of the connecting portion of the widthwise groove to the circumferential main groove, and the cross-sectional area B is the connection of the sub-groove to the widthwise groove. The cross-sectional area of the tire circumferential direction cross section of the tire portion is referred to, and the cross-sectional area C refers to the cross-sectional area of the tire circumferential direction cross section of the connecting portion to the tread end of the widthwise groove.

Furthermore, in the present invention, the ratio B / C is preferably 0.10 to 0.60.
It is because drainage can be further improved by setting it as said range.

  ADVANTAGE OF THE INVENTION According to this invention, the pneumatic tire which made the wet performance of a tire and the performance on snow compatible can be provided.

It is a development view showing a tread surface of a tire concerning one embodiment of the present invention. (A)-(c) It is a figure for demonstrating cross-sectional area A, B, and C. FIG. (A) It is a top view for demonstrating the case where a bottom raising part is provided in the width direction groove | channel. (B) It is DD sectional drawing of the figure shown to (a). It is an expanded view which shows the tread surface of the tire concerning other embodiment of this invention.

  Hereinafter, a pneumatic tire (hereinafter referred to as a tire) according to an embodiment of the present invention will be described in detail with reference to the drawings. Note that the internal structure of the tire is the same as that of a conventional tire, and thus the description thereof is omitted.

FIG. 1 is a development view showing a tread surface of a tire according to an embodiment of the present invention. FIG. 1 is a developed view of the tread surface when the tire is mounted on an applied rim, filled with a specified internal pressure, and brought into an unloaded state.
As shown in FIG. 1, the tire includes a tread tread surface 1 and at least one circumferential main groove 2 continuously extending in the tread circumferential direction and a plurality of width directions extending inward in the tread width direction from the tread end TE. A groove 3 and a plurality of sub-grooves 4 extending across the width direction groove 3 are provided.
In the illustrated example, this tire has one circumferential main groove 2 extending in the tread circumferential direction on the tire equatorial plane CL on the tread tread surface 1, and the plurality of widthwise grooves 3 are formed from the tread end TE. It extends inward in the tread width direction so as to incline in the tread width direction, and is connected to the circumferential main groove 2 and terminates. As shown in FIG. 1, the width direction groove | channel 2 has a groove width gradually increasing toward the tread width direction outer side, and the inclination angle with respect to the tread width direction is gradually decreased. Further, in the illustrated example, a plurality of sub-grooves 4 are connected to two widthwise grooves 3 adjacent in the tread circumferential direction, and the space between the two adjacent widthwise grooves 3 is in the tread circumferential direction. It extends at an angle.
A plurality of blocks 5 are defined by the circumferential main groove 2, the width direction groove 3, and the sub-groove 4, and a plurality of zipes 6 extending in a zigzag manner are provided on the surface of the block 5 in the illustrated example. It has been.

Here, as shown in FIGS. 2A to 2C, the cross-sectional area of the connection portion 7 a to the circumferential main groove 2 at the inner end portion in the tread width direction of the width direction groove 3 is defined as A (mm ² ), The end of the groove 4 on one side in the tread circumferential direction (in the illustrated example, the portion of the widthwise groove 3 that divides the block 5 extends in the tread width direction outward direction). The cross-sectional area of the connecting portion 7b to the widthwise groove 3 is B (mm ² ), and the cross-sectional area of the connecting portion 7c to the tread end TE of the outer end portion in the tread width direction of the widthwise groove 3 is C (mm ² ). The tire of this embodiment satisfies A <B <C.
Thus, in the tire of the present invention, it is important to satisfy A <C and B <C.
Hereinafter, the operation and effect when the tire is mounted on the vehicle so that “one side in the tread circumferential direction” is the kicking side of the block will be described.

According to the tire of the present embodiment, the cross-sectional area A on the inlet side of the water flowing in the width direction groove 3 is reduced, the cross-sectional area B of the junction with the sub groove 4 is reduced, and the water flowing in the width direction groove 3 Since the cross-sectional area C on the outlet side is increased, the generation of turbulent flow due to an increase in the amount of water that merges from the circumferential main groove 2 to the widthwise groove 3 and the subgroove 4 merges into the widthwise groove 3. Occurrence of turbulent flow due to an increase in the amount of water can be suppressed, and the drainage effect with the widthwise groove 3 as one main water channel can be enhanced, and the drainage of the tire can be improved.
Further, according to the tire of the present embodiment, by increasing the cross-sectional area C of the widthwise groove 3, the snow digging friction is increased and the traction performance on snow is improved.

Here, the ratio A / C is preferably 0.24 or less, and more preferably 0.17 or less. This is because generation of turbulent flow due to an increase in the amount of water that merges from the circumferential main groove 2 to the width direction groove 3 can be suppressed, and the drainage effect using the width direction groove 3 as the main water flow path can be further enhanced.
On the other hand, the ratio A / C is preferably set to 0 or more in order to secure the contact area and ensure the running performance on the dry road surface.
In the case of A = 0, the width direction groove 4 is connected to the circumferential main groove 2 with a groove width of 0 mm at the connection portion, and the block 5 partitioned by the width direction groove 4 at the connection portion. Is divided in the tread circumferential direction.

Further, the ratio B / C is preferably 0.60 or less, and more preferably 0.42 or less. This is because it is possible to suppress the generation of turbulent flow due to an increase in the amount of water that merges from the sub-groove 4 to the width direction groove 3 and to further enhance the drainage effect using the width direction groove 3 as the main water flow path.
On the other hand, in order to ensure the discharge amount of water from the sub-groove 4, it is preferable that the ratio B / C is 0.07 or more.

Here, the cross-sectional area A is preferably 0 to 18 mm ² .
This is because by setting the cross-sectional area A to 0 mm ² or more, the traction performance on snow can be improved, and the contact performance can be ensured to ensure the running performance on the dry road surface. On the other hand, by setting the cross-sectional area A to 18 mm ² or less, it is possible to suppress the generation of the above-described turbulent flow and further enhance the drainage effect using the widthwise groove 3 as the main water flow path.
Further, the cross-sectional area B is preferably 8~46mm ^2.
By setting the cross-sectional area B to 8 mm ² or more, snow clogging can be suppressed, and the amount of water discharged from the ^secondary groove 4 can be secured, while the cross-sectional area B is set to 46 mm ² or less. This is because the generation of the turbulent flow described above can be suppressed, and the drainage effect with the widthwise groove 3 as the main water flow path can be further enhanced.
Furthermore, the cross-sectional area C is preferably 77 to 110 mm ² .
By setting the cross-sectional area C to 77 mm ² or more, the flow rate of water flowing in the width direction groove 3 serving as the main water flow path can be secured to improve drainage, while the cross-sectional area C is set to 110 mm ² or less. By doing so, it is possible to secure a ground contact area and ensure traveling performance and the like on a dry road surface.

Moreover, as shown to Fig.2 (a), it is preferable that the groove width w1 in the cross section of the connection part 7a to the circumferential direction main groove 2 of the tread width direction inner side edge part of the width direction groove | channel 3 shall be 0-2 mm. . This is because, by setting it to 0 mm or more, the traction performance on snow can be improved, and the contact performance can be ensured to ensure the running performance on the dry road surface. On the other hand, by making it 2 mm or less, it is because generation | occurrence | production of the turbulent flow mentioned above can be suppressed and the drainage effect which used the width direction groove | channel 3 as the main water flow path can be heightened more.
Furthermore, the groove depth (maximum depth) h1 in the cross section of the connecting portion 7a of the width direction groove 3 is preferably 1 to 9.2 mm.
It is because drainage can be ensured by setting it as 1 mm or more, and on the other hand, block rigidity can be ensured and performance on snow can be ensured by setting it as 9.2 mm or less.
Here, as for the groove depth of the width direction groove, as shown in FIGS. 3A and 3B, the cross section of the connection portion 6 to the circumferential main groove 2 at the inner end portion in the tread width direction of the width direction groove 3. A bottom raised portion 8 can be provided. In this case, it is preferable that the maximum depth h4 of the portion where the bottom of the width direction groove is not raised is 1 to 9.2 mm. It is because drainage can be ensured by setting it as 1 mm or more, and on the other hand, block rigidity can be ensured and performance on snow can be ensured by setting it as 9.2 mm or less.
In the present specification, the “groove width” refers to the opening width to the tread tread when the tire is mounted on the applicable rim, filled with the specified internal pressure, and is in a no-load state.

In addition, as shown in FIG. 2B, the groove width w2 in the cross section of the connecting portion 7b to the widthwise groove 3 at the end on the one side in the tread circumferential direction of the sub-groove 4 is 2 to 5 mm. preferable. By setting it to 2 mm or more, snow clogging can be suppressed, and the amount of water discharged from the sub-groove 4 can be secured. On the other hand, by setting it to 5 mm or less, generation of the turbulent flow described above can be suppressed. This is because the drainage effect using the width direction groove 3 as the main water flow path can be further enhanced.
Moreover, as shown in FIG.2 (b), it is preferable that the groove depth (maximum depth) h2 in the cross section of the said connection part 7b of the subgroove 4 shall be 4-9.2 mm. It is because drainage can be ensured by setting it as 4 mm or more, and on the other hand, block rigidity can be ensured and performance on snow can be ensured by setting it as 9.2 mm or less.
Here, as shown in FIG. 1, for example, when two or more sub grooves 4 communicating between two width direction grooves 3 adjacent to each other in the tread circumferential direction are provided, the sub grooves 4 on the inner side in the tread width direction are used. It is preferable to make the depth of the groove deeper than the depth of the auxiliary groove 4 on the outer side in the tread width direction. This is because the edge effect of the block can be further exhibited and the performance on the snow of the tire can be improved.

Furthermore, as shown in FIG.2 (c), it is preferable that groove width w3 in the cross section of the connection part 7c to the tread end TE of the tread width direction outer side edge part of the width direction groove | channel 3 shall be 9-12 mm. By setting it to 9 mm or more, it is possible to secure the flow rate of water flowing in the width direction groove 3 that becomes the main water flow path and improve drainage, while by setting it to 12 mm or less, the grounding area is secured. This is because driving performance and the like on a dry road surface can be ensured.
Moreover, it is preferable that the groove depth (maximum depth) h3 in the cross section of the said connection part 7c of the width direction groove | channel 3 shall be 7.0-9.2 mm.
It is because drainage can be ensured by setting it as 7.0 mm or more, and on the other hand, block rigidity can be ensured and performance on snow can be ensured by setting it as 9.2 mm or less.

Here, in the present invention, the cross-sectional area A and the cross-sectional area B preferably satisfy A <B.
This is because by making the cross-sectional area B larger than the cross-sectional area A, the edge effect in the lateral direction can be further exhibited and the performance on snow can be improved.

Here, as shown in FIGS. 3A and 3B, the circumferential main groove 2 and the width direction groove 3 can have different groove depths, while the groove depths should be the same depth. You can also.
3A and 3B, a bottom raised portion 8 is provided in the widthwise groove 3, and the groove depth of the widthwise groove 3 is shallower than the groove depth of the circumferential main groove 2 in the bottom raised portion 8. However, in the portion where the bottom is not raised, the depth is made deeper than the groove depth of the circumferential main groove 2. The bottom raising portion 8 can block a large amount of water from the circumferential main groove 2 to the width direction groove 3 and suppress the generation of turbulent flow. This is because the drainage amount of the groove 3 is increased, and these effects are combined to improve the drainage performance of the tire.

Here, the circumferential main groove 2 is a tread contact width between both ends of the contact surface in the tire width direction in a state where a tire is mounted on an applicable rim, a specified internal pressure is filled, and a load corresponding to the maximum load capacity is applied. In this state, at least one of the tread contact widths in the tread ground width centered on the tire equator plane CL (10% of the tread contact width on both sides in the tread width direction from the tire equator plane) is disposed. Is preferred.
This is because the drainage at the tire center can be enhanced.
Moreover, it is preferable that the circumferential main groove 2 extends in the tread circumferential direction or inclines at an angle of 45 ° or less with respect to the tread circumferential direction.
Furthermore, as shown in FIG. 3, the groove width W of the circumferential main groove 2 is preferably 1 to 10 mm. This is because both drainage and block rigidity can be achieved.
The groove depth H of the circumferential main groove 2 is preferably 4 to 9.2 mm.
By setting the groove depth H of the circumferential main groove 2 to 4 mm or more, drainage can be ensured, while on the other hand, by setting the groove depth H of the circumferential main groove 2 to 9.2 mm or less, This is because driving performance on a dry road surface can be ensured.

Moreover, it is preferable that the width direction groove | channel 3 extends in the tread width direction, or inclines at an angle of 45 degrees or less with respect to the tread width direction.
Furthermore, as shown in FIG. 1, it is preferable that the groove width of the width direction groove | channel 3 increases gradually as it goes to a tread width direction outer side. This is because the water drainage from the tire center side to the shoulder side can be increased to further improve the drainage performance of the tire.
In addition, the width direction grooves 3 are preferably arranged at a pitch interval of 16 to 20 mm in the tread circumferential direction. This is because wet performance and performance on snow can be made more compatible.
Moreover, as shown in FIG. 1, it is preferable that the width direction groove | channel 3 provides a phase difference in the tread circumferential direction between the tread width direction half parts which make the tire equatorial plane CL a boundary. This is because pattern noise can be reduced.

Furthermore, the sub-groove 4 preferably extends in the tread circumferential direction or extends at an angle of 45 ° or less with respect to the tread circumferential direction.
It is because drainage can be improved.

Here, in the present invention, it is preferable to provide notches at least at one corner in the tread circumferential direction and outside in the tread width direction among the corners of at least one block 5. When the tire is mounted on the vehicle so that one side in the circumferential direction of the tread is the kicking side of the block, it is possible to suppress the turbulent water flow in the vicinity of the corner portion where the notch portion is provided. The drainage effect using the directional groove 3 as the main water flow path can be enhanced, and the drainage of the tire can be further improved. In addition, since the positions where the cutout portions are provided are corner portions, the actual contact area is hardly reduced, and traveling performance on dry road surfaces and traveling performance on icy and snowy road surfaces can be ensured.
Further, in the present invention, as shown in FIG. 1, it is preferable to provide a notch portion only at one corner of the at least one block 5 on one side in the tread circumferential direction and outside in the tread width direction. Notches are formed so that the corners are rounded). That is, it is preferable not to provide a notch at the corner on one side in the tread circumferential direction and on the inner side in the tread width direction and on the two corners on the other side in the tread circumferential direction.
If notches are provided in the corners on the stepping side of the block, the flow of water from the width direction groove 3 to the sub-groove 4 increases and turbulence occurs, and the drainage performance with the width direction groove 3 as the main water flow path is reduced. This is because the drainage can be further improved by providing a cutout portion only in the specific corner portion. In addition, if a notch is provided at one corner in the tread circumferential direction (block kick-out side) and inside the tread width direction, the drainage is improved, but the rigidity on the block kick-out side is reduced. This is because, in some cases, the running performance on the dry road surface may be deteriorated, so that the running performance on the dry road surface can be ensured by providing the notched portion only at the specific corner portion.

  Moreover, it is preferable that the corner | angular part which provided the said notch part has a roundness with a curvature radius of 0.5-4.0 mm. This is because, while ensuring drainage, it is possible to secure a ground contact area and ensure performance on snow.

In the present invention, in particular, when the corners of the block 5 are formed to be rounded with a predetermined radius of curvature as shown in FIG. 1, the tread width direction centered on the tire equatorial plane CL is used. In the at least one set of two blocks 5 adjacent to each other in the tread width direction in the same half portion, the two blocks 5 of the set are respectively at least the tread circumferences of the corner portions of the blocks 5. A cutout portion is provided at a corner on one side in the direction and on the outer side in the tread width direction, and the cutout portion of one block 5 located on the outer side in the tread width direction is provided among the at least one pair of the two blocks 5. The radius of curvature R1 (mm) of the roundness of the corner is the radius of curvature R2 (m of the roundness of the corner provided with the notch of the other block 5 located adjacent to the inside of the one block 5 in the tread width direction. ) Is preferably greater than.
This is because the drainage can be further improved by increasing the water flow on the outer side in the tread width direction.

  In the present invention, the negative rate of the tread surface (ratio of the groove area in the tread surface to the area of the tread surface) is preferably 33 to 40%. This is because, while ensuring drainage, it is possible to secure a ground contact area and ensure performance on snow. Furthermore, in the present invention, the groove area of the width direction groove is preferably larger than the groove areas of the circumferential main groove and the sub groove, in order to allow the width direction groove 3 to sufficiently function as the main water flow path. 50% or more of the width direction groove is preferably the groove area of the width direction groove.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to said embodiment at all. For example, FIG. 1 illustrates a case where there is only one circumferential main groove 2, but the tire of the present invention has a plurality of circumferential main grooves 2 on the tread surface 1, for example, FIG. 4. As described above, three of the three circumferential main grooves 2 may be connected to the circumferential main groove 2 at the center in the tread width direction. In this case, for example, as shown in FIG. 4, only one sub groove 4 can be provided between two width direction grooves 3 adjacent to each other in the tread circumferential direction. In this case, the cross-sectional area A is the cross-sectional area of the connecting portion to the circumferential main groove 2 at the center in the tread width direction among the three circumferential main grooves 2 of the width direction groove 3. That is, when the width direction groove 3 is connected to a plurality of circumferential direction main grooves 2, the cross-sectional area A is connected to the circumferential direction main groove 2 located on the innermost side in the tread width direction among the circumferential direction main grooves 2 The cross-sectional area of the part.

In order to confirm the effects of the present invention, tires according to invention examples and comparative examples were made on a trial basis.
The specifications of each tire are shown in Table 1.
For each of the tires described above, the tires of the tire size 205 / 55R16 are assembled to an applicable rim, the internal pressure is set to 220 kPa, and the vehicle is mounted on a passenger car to evaluate wet performance, performance on snow, and running performance on a dry road. A test was conducted.

<Wet performance>
On the test course with a water depth of 7 mm, the reciprocal of the braking distance from the 80 km / h speed until the vehicle completely stopped was taken.
The evaluation results are shown in Table 1. In Table 1, index evaluation is performed with a relative value where Comparative Example 1 is set to 100, and a larger numerical value indicates better wet performance.
<Snow performance>
The reciprocal of the time from the stop state to 30 km / h was taken.
The evaluation results are shown in Table 1. In Table 1, index evaluation is performed using relative values with Comparative Example 1 as 100, and a larger value indicates better performance on snow.
<Driving performance on dry road>
On the dry road surface, the reciprocal of the braking distance from the vehicle at 80 km / h until the vehicle completely stopped was taken.
The evaluation results are shown in Table 1. In Table 1, index evaluation is performed with a relative value with Comparative Example 1 being 100, and a larger value indicates better running performance on a dry road surface.

As shown in Table 1, the tire according to the invention example in which the relationship between A, B, and C is optimized has both wet performance and on-snow performance compared to the tire according to the comparative example . I understand.
Furthermore, compared with Comparative Examples 3 and 6 and Invention Examples 3 to 5, Invention Examples 3 to 5 in which the value of the ratio A / C is optimized are compared with Comparative Examples 3 and 6 in terms of wet performance and on-snow performance. It can be seen that both can be achieved at higher dimensions.
Further, by comparison of Inventive Examples 7-9 and Comparative Examples 4 and 5, invention examples 7-9 that optimization of the value of the ratio B / C, as compared with Comparative Examples 4 and 5, the wet performance and snow performance It can be seen that both can be achieved at higher dimensions.

  ADVANTAGE OF THE INVENTION According to this invention, the pneumatic tire which made the wet performance of a tire and the performance on snow compatible can be provided.

DESCRIPTION OF SYMBOLS 1 Tread surface 2 Circumferential main groove 3 Width direction groove 4 Sub groove 5 Block 6 Sipe 7a, 7b, 7c Connection part 8 Bottom raising part TE Tread edge CL Tire equatorial surface

Claims (5)

The tread tread has at least one circumferential main groove extending continuously in the tread circumferential direction, a plurality of widthwise grooves extending inward in the tread width direction from the tread end and connected to the circumferential main groove, and the width A plurality of sub-grooves extending across the direction groove,
A cross-sectional area of the connecting portion to the circumferential main groove at the inner end portion in the tread width direction of the width direction groove is A (mm ² ), and the end portion on the one side in the tread circumferential direction of the sub groove is connected to the width direction groove. When the cross-sectional area of the connecting portion is B (mm ² ), and the cross-sectional area of the connecting portion to the tread end of the tread width direction outer end portion of the width direction groove is C (mm ² ),
A <C and B <C
Meets, the ratio A / C is from 0 to 0.24 and the ratio B / C is from 0.07 to 0.60,
The widthwise groove has a bottom raised portion, and the groove depth of the widthwise groove is shallower than the groove depth of the circumferential main groove at the bottom raised portion, and the groove depth of the circumferential main groove at a portion not raised at the bottom. and wherein the deep, the pneumatic tire. The pneumatic tire according to claim 1 , wherein one side in the tread circumferential direction is a kicking side of a block defined by the circumferential main groove and the width direction groove . The pneumatic tire according to claim 1 or 2, wherein the width direction grooves are arranged at a pitch interval of 16 to 20 mm in a tread circumferential direction. The pneumatic tire according to any one of claims 1 to 3, wherein the pneumatic tire has notches at corners on one side in the tread circumferential direction and outside in the tread width direction. 5. The pneumatic tire according to claim 1, wherein the circumferential main groove extends in a tread circumferential direction, and the sub-groove extends while being inclined with respect to the tread circumferential direction.

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