JP7172348B2 - tire - Google Patents

Description

TECHNICAL FIELD The present invention relates to a tire having a tread portion provided with blocks.

Patent Document 1 below describes a tire in which a tread portion is provided with a center main groove, an outer lateral groove extending axially outward from the center main groove, and an inner lateral groove extending axially inward from the center main groove. is described. The center main groove includes an outer groove portion, an inner groove portion, and an inclined portion connecting the outer groove portion and the inner groove portion. The inner lateral groove communicates with a first intersection portion where the inner groove portion and the inclined portion intersect, and the outer lateral groove communicates with a second intersection portion where the inclined portion and the outer groove portion intersect. In such a tire, the land portions on both sides of the center main groove maintain high rigidity, and the inner lateral grooves, the outer lateral grooves, and the intersections can form strong snow columns, resulting in high on-snow performance. have

JP 2017-121919 A

In recent years, it has been desired to further improve on-snow performance. For this reason, for example, it is conceivable to increase the angle of the inner lateral groove and the outer lateral groove with respect to the axial direction of the tire to increase the edge component thereof. However, such a tire has a problem that the wear resistance performance is deteriorated due to variations in the rigidity of the land portions where the inner lateral grooves and the outer lateral grooves are provided.

SUMMARY OF THE INVENTION The present invention has been devised in view of the above circumstances, and its main object is to provide a tire capable of improving performance on snowy roads while maintaining wear resistance performance.

The present invention relates to a tire, wherein a tread portion includes a first block, a second block adjacent to the first block in the tire axial direction and arranged in the tire circumferential direction, and the second block adjacent to the tire circumferential direction. The first block has a first block wall extending in the tire circumferential direction on the side of the lateral groove, and the first block wall has a recess recessed inwardly of the first block. The recess overlaps the opening of the lateral groove on the first block side in the tire circumferential direction, and the length of the recess in the tire circumferential direction is equal to the length of the first block wall in the tire circumferential direction. The distance in the tire circumferential direction between the intermediate position of the recess in the tire circumferential direction and the intermediate position of the first block wall in the tire circumferential direction is 30% to 70% of the height of the first block wall. It is 10% or less of the length in the tire circumferential direction.

In the tire according to the present invention, it is preferable that the concave portion has a rectangular shape when viewed from above the tread portion.

In the tire according to the present invention, it is preferable that the recess is tapered toward the inside of the first block in a plan view of the tread portion.

In the tire according to the present invention, the concave portion includes a pair of axial portions extending from the first block wall while being spaced apart in the tire circumferential direction, and a circumferential portion joining the pair of axial portions. The length of the axial portion in the tire axial direction is preferably 5% to 11% of the length of the circumferential portion in the tire circumferential direction.

In the tire according to the present invention, the distance in the tire circumferential direction between the intermediate position of the opening in the tire circumferential direction and the intermediate position of the recess in the tire circumferential direction is 40 times the length of the recess in the tire circumferential direction. % or less.

In the tire according to the present invention, the first block is provided with a sipe, and the sipe extends from the first block wall and ends before an intermediate position of the first block in the tire axial direction. It preferably contains one sipe.

In the tire according to the present invention, it is desirable that the first sipe extends without crossing the recess.

In the tire according to the present invention, the first sipe includes a first short sipe and a first long sipe having a longer axial length than the first short sipe, and the first short sipe and the opening It is preferable that a tire circumferential distance between the opening and the intermediate position in the tire circumferential direction is smaller than a tire circumferential distance between the first long sipe and the intermediate position of the opening.

In the tire according to the present invention, it is preferable that the first short sipe is separated from the first long sipe in the tire circumferential direction via the recess.

In the tire according to the present invention, the first block has a second block wall arranged on the opposite side of the first block wall in the tire axial direction, the sipe extends from the second block wall, and , including a second long sipe that is cut off before the intermediate position of the first block, and the separation distance between the end of the first long sipe and the end of the second long sipe is the length of the recess in the tire circumferential direction It is desirable to be 1/5 to 1/3 of the height.

In the tire according to the present invention, the first long sipe has a first portion extending parallel to the first short sipe, a second portion extending toward the center of the first block, and the first portion and the second portion. Preferably, it includes a bend that bends into two parts, said bend being provided with a tie bar with a raised sipe bottom.

In the tire according to the present invention, the sipes include a plurality of the first sipes extending from the first block wall and arranged in the tire circumferential direction, and the circumferential distance between the first sipes adjacent to each other in the tire circumferential direction is L9 preferably satisfies the following formula (1). However, n is the number of the first sipes.
La/n<L9<La/(n+1) (1)

In the tire of the present invention, a tread portion is provided with first blocks, second blocks adjacent to the first blocks in the tire axial direction, and lateral grooves extending between the second blocks. In the first block, a first block wall on the side of the lateral groove is provided with a recess that overlaps the opening of the lateral groove in the tire circumferential direction. The length of the concave portion in the tire circumferential direction is 30% or more of the length of the first block wall in the tire circumferential direction. Such a concave portion suppresses movement of the snow flowing from the lateral grooves in the tire circumferential direction and receives the snow to form a solid snow mass when the vehicle turns on a snowy road. Such snow masses exert a large shear force on the snow column, which enhances traction during cornering and suppresses skidding.

The length of the recess in the tire circumferential direction is 70% or less of the length of the first block wall in the tire circumferential direction. Since such recesses suppress a decrease in rigidity of the first block, the wear resistance performance of the first block is maintained at a high level.

In addition, the distance in the tire circumferential direction between the intermediate position of the recess in the tire circumferential direction and the intermediate position of the first block wall in the tire circumferential direction is 10 times the length of the first block wall in the tire circumferential direction. % or less. As a result, the snow flowing from the lateral grooves is held near the center of the first block in the tire circumferential direction, and is further suppressed from escaping to both sides in the tire circumferential direction. Therefore, the first block can form a stronger snow mass in the concave portion, thereby exhibiting excellent performance on snowy roads.

FIG. 2 is an enlarged development view of a part of the tread portion of the tire according to the embodiment of the present invention; FIG. 2 is an enlarged view of FIG. 1; FIG. 2 is an enlarged view of FIG. 1; FIG. 2 is an enlarged view of FIG. 1; FIG. 3 is a cross-sectional view taken along line AA of FIG. 2; FIG. 4 is an exploded view of a tread portion of another embodiment; FIG. 7 is an exploded view of the tread portion of FIG. 6;

An embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 is an enlarged development view of a part of the tread portion 2 of the tire 1 of this embodiment. INDUSTRIAL APPLICABILITY The present invention can be used for various tires such as pneumatic tires for passenger cars and heavy loads, and non-pneumatic tires in which the interior of the tire is not filled with pressurized air. The tire 1 of this embodiment is an all-season tire suitable for four-wheel drive vehicles.

The tread portion 2 of the present embodiment includes a first block 3, a second block 4 adjacent to the first block 3 in the tire axial direction and arranged in the tire circumferential direction, and second blocks 4, 4 adjacent in the tire circumferential direction. A transverse groove 5 is provided extending therebetween. The tread portion 2 includes a pair of longitudinal grooves 6A, 6A arranged on both sides of the first block 3 in the tire axial direction, and a pair of lateral grooves 6B, 6B arranged on both sides of the first block 3 in the tire circumferential direction. is provided.

The first block 3 includes a first block wall 7 extending in the tire circumferential direction on the lateral groove 5 side, and a second block wall 8 disposed on the opposite side of the tire axial direction from the first block wall 7 . Further, in this embodiment, the first block 3 includes a pair of third block walls 9, 9 extending in the axial direction of the tire by connecting both ends of the first block wall 7 and the second block wall 8. As shown in FIG. In this embodiment, the pair of third block walls 9 extend parallel to each other and are inclined with respect to the tire axial direction. The first block wall 7, the second block wall 8 and the third block wall 9 are formed as groove walls extending outward in the tire radial direction from the groove bottoms of the respective grooves 6A and 6B. The first block 3 is formed, for example, in a substantially parallelogram shape in plan view. The first block 3 is not limited to such a parallelogram shape, and various shapes such as a rectangular shape and a trapezoidal shape are adopted.

The first block wall 7 of this embodiment is provided with a recess 10 that is recessed inside the first block 3 . The first block wall 7 includes a recess 10 and a pair of ends 11 arranged on both sides of the recess 10 and connected to each third block wall 9 in this embodiment.

The end portion 11 extends linearly along the tire circumferential direction, for example. The end portion 11 is not limited to such a form, and may be formed, for example, in an arcuate shape or a wavy shape that protrudes toward the second block 4 side.

The recess 10 of the present embodiment overlaps the opening 5A of the lateral groove 5 on the side of the first block 3 in the tire circumferential direction. As a result, when turning on a snowy road, snow flowing from the lateral grooves 5 into the recesses 10 is suppressed from moving to both sides in the tire circumferential direction, and a strong snow mass is formed by the lateral force during turning. be. As a result, a large snow column shear force is exerted, which enhances traction during cornering and suppresses skidding. In this embodiment, the recess 10 overlaps the entire opening 5A of the lateral groove 5 in the tire circumferential direction. This allows the snow in the lateral grooves 5 to smoothly enter the recesses 10 . In addition, the recessed part 10 is not limited to such an aspect, It is sufficient that the recessed part 10 and at least a part of the opening 5A overlap in the tire circumferential direction.

FIG. 2 is an enlarged view of FIG. As shown in FIG. 2, the length (maximum length along the tire circumferential direction) L1 of the recess 10 in the tire circumferential direction is equal to the length La (shown in FIG. 1) of the first block wall 7 in the tire circumferential direction. 30% or more of Such recesses 10 increase the volume of the snow mass and increase the shear force of the snow column. Further, the length L1 of the recess 10 is 70% or less of the length La of the first block wall 7. As shown in FIG. As a result, a large decrease in rigidity of the first block 3 is suppressed, so the wear resistance performance of the first block 3 is maintained at a high level.

The distance Lb in the tire circumferential direction between the intermediate position 10c of the recess 10 in the tire circumferential direction and the intermediate position 7c of the first block wall 7 in the tire circumferential direction is 10% of the length La of the first block wall 7 in the tire circumferential direction. It is below. As a result, snow flowing from the lateral grooves 5 is held near the center of the first block wall 7 in the tire circumferential direction, and can escape to both sides of the first block 3 in the tire circumferential direction (outside the third block wall 9). Suppressed. Therefore, the first block 3 can form a stronger snow mass in the recess 10 . An intermediate position 10 c of the recess 10 is a position on the maximum length L1 of the recess 10 .

In this embodiment, the recess 10 is formed as a notch having the same depth in the tire radial direction as the depth (not shown) of the vertical groove 6A between the first block 3 and the second block 4. . Such a recessed portion 10 increases the volume of the snow mass, thereby improving performance on snowy roads. The recessed portion 10 is not limited to such an aspect, and may be formed as a stepped notch having a depth in the tire radial direction smaller than the depth of the vertical groove 6A.

In the present embodiment, the recessed portion 10 has a rectangular shape in a plan view of the tread portion 2 . Such recesses 10 can effectively store the snow in the recesses 10 . Also, excessive reduction in rigidity of the first block 3 is suppressed.

The concave portion 10 is, for example, tapered toward the inside of the first block 3 in a plan view of the tread portion 2 . Such recesses 10 help to keep the rigidity of the first block 3 high.

In this embodiment, the recessed portion 10 includes a pair of axial portions 13, 13 extending from the first block wall 7 while being spaced apart in the tire circumferential direction, and a circumferential portion 14 joining the pair of axial portions 13, 13. I'm in. The length L3 of the axial portion 13 in the tire axial direction is preferably 5% to 11% of the length L4 of the circumferential portion 14 in the tire circumferential direction. As a result, it is possible to prevent a decrease in the rigidity of the first block 3 while ensuring snow that can be stored in the recess 10 .

The axial portion 13 and the circumferential portion 14 extend linearly in this embodiment. Such an axial portion 13 serves to smoothly shear the snow mass. In addition, the circumferential portion 14 helps to firmly form snow masses in the concave portion 10 . In addition, the circumferential portion 14 is not limited to such an aspect, and may, for example, extend in a convex arcuate shape or a wavy shape toward the inside of the first block 3 .

FIG. 3 is an enlarged view of FIG. As shown in FIG. 3, the shortest distance L5 between the intermediate position 10c of the recess 10 and the imaginary line 5k obtained by extending the groove center line 5h of the lateral groove 5 toward the first block 3 is 30% of the length L1 of the recess 10. % or less. As a result, the snow in the lateral grooves 5 can smoothly flow into the recesses 10. - 特許庁In addition, by utilizing the pressing force of the snow flowing in the lateral grooves 5, the snow lumps in the concave portions 10 are further pressed and hardened, thereby suppressing skidding during turning. The groove center line 5h is a line segment that connects the intermediate position 5c of the opening 5A and the intermediate position 5d of the opening 5B on the side opposite to the first block 3 of the lateral groove 5 with a straight line.

An imaginary groove edge Vn obtained by smoothly extending the groove edge 5 a of the lateral groove 5 toward the first block 3 preferably intersects the recess 10 . As a result, the snow in the lateral grooves 5 flowing along the groove edges 5a exerts a pressing force on the snow in the recesses 10 to form hard snow masses. In this embodiment, imaginary groove edges Vn, Vn of the groove edges 5a, 5a on both sides of the lateral groove 5 intersect the circumferential portion 14 of the recess 10 . As a result, the above effects are effectively exhibited.

As shown in FIG. 1, the second block wall 8 of this embodiment, like the first block wall 7, has a recess 10 and end portions 11 connecting the recess 10 and the third block walls 9 on both sides thereof. is provided. In this embodiment, the recess 10 of the second block wall 8 is formed in the same manner as the recess 10 of the first block wall 7, so detailed description thereof will be omitted.

The first block 3 is provided with a sipe 15 in this embodiment. In this specification, a sipe 15 is an incision having a width w perpendicular to its length of less than 1.5 mm, to be distinguished from a groove having a width of 1.5 mm or more.

Sipe 15 of this embodiment contains the 1st Sipe 15A and the 2nd Sipe 15B. In this embodiment, the first sipe 15A extends from the first block wall 7 and is discontinued before the intermediate position 3c of the first block 3 in the tire axial direction. In this embodiment, the second sipe 15B extends from the second block wall 8 and is discontinued before the intermediate position 3c of the first block 3 in the tire axial direction. Such a sipe 15 exerts an edge effect (frictional force for excavating a snowy road) to improve performance on a snowy road, while suppressing an excessive decrease in stiffness of the first block 3 .

FIG. 4 is an enlarged view of FIG. As shown in FIG. 4, the first sipe 15A extends without crossing the recess 10 in this embodiment. That is, the first sipe 15A extends from the end portion 11 in this embodiment. As a result, a decrease in rigidity of the concave portion 10 of the first block 3 is suppressed, and a strong snow mass can be formed.

The first sipe 15A includes a first short sipe 16 and a first long sipe 17 longer than the first short sipe 16 in the tire axial direction.

In this embodiment, the first short sipe 16 is spaced apart from the first long sipe 17 via the recess 10 in the tire circumferential direction. Thereby, a decrease in rigidity of the end portion 11 is suppressed.

A distance L6 in the tire circumferential direction between the first short sipe 16 and the intermediate position 5c of the opening 5A in the tire circumferential direction is equal to the distance L6 between the first long sipe 17 and the intermediate position 5c of the opening 5A in the tire circumferential direction. is preferably smaller than the separation distance L7. That is, the first short sipe 16 is arranged closer to the lateral groove 5 than the first long sipe 17 is. A portion of the first block 3 in the vicinity of the first short sipe 16 is less rigidly lowered than a portion of the first block 3 in the vicinity of the first long sipe 17 . Therefore, when the separation distance L6 is smaller than the separation distance L7, the snow flowing from the lateral grooves 5 is firmly solidified in the recesses 10 near the first short sipes 16 . Although not particularly limited, the distance L6 is desirably 60% to 90% of the distance L7.

The first short sipe 16 extends linearly in this embodiment. The first short sipe 16 extends parallel to the third block wall 9, for example. The first long sipe 17, in this embodiment, has a first portion 22 extending parallel to the first short sipe 16, a second portion 23 extending toward the center of the first block 3, and a portion between the first portion 22 and the second portion. It includes a bent portion 24 that bends in tandem with the portion 23 . Such a first long sipe 17 exerts an edge effect in two directions and stabilizes turning traveling on a snowy road.

An angle θ1 formed between the first portion 22 and the second portion 23 is greater than 90 degrees. This suppresses a decrease in rigidity of the first block 3 due to the provision of the first long sipe 17 .

FIG. 5 is a cross-sectional view taken along line AA of FIG. As shown in FIG. 5, in the present embodiment, the first long sipe 17 is provided with a tie bar 26 at the bent portion 24 from which the sipe bottom 15s rises. Such a tie bar 26 suppresses a decrease in rigidity of the bent portion 24 on which a large stress acts.

Desirably, the length L8 of the tie bar 26 is, for example, 2 mm or more. Moreover, it is desirable that the height h1 of the tie bar 26 in the tire radial direction from the sipe bottom 15s is 1/3 or more of the sipe depth ha of the first long sipe 17 excluding the tie bar 26. This effectively suppresses a decrease in rigidity of the bent portion 24 . If the height h1 of the tie bar 26 is excessively large, the edge effect may be reduced and the improvement of snow road performance may be suppressed. For this reason, it is desirable that the height h1 of the tie bar 26 is 1/2 or less of the height ha of the first long sipe 17. As shown in FIG.

Although not particularly limited, the depth h of the sipe 15 is 50% or more of the block height H when the block height H of the first block 3 is greater than 3.2 mm. - (Minus) 1.6 mm or less is desirable. Further, the depth h of the sipe 15 is preferably 50% or less of the block height H when the block height H is 3.2 mm or less.

As shown in FIG. 1 , the second sipe 15B of this embodiment is symmetrical with the first sipe 15A at any point on the tread surface of the first block 3 . As a result, the difference in rigidity between both sides of the first block 3 in the axial direction of the tire is reduced, thereby suppressing a decrease in wear resistance and uneven wear resistance. Thus, the second sipe 15B is formed of the second short sipe 19 and the second long sipe 20 in this embodiment. Moreover, it is desirable that the second long sipe 20 is provided with a tie bar (not shown) at the bent portion 24 thereof, similarly to the first long sipe 17 .

The separation distance Lc between the end 17e of the first long sipe 17 and the end 20e of the second long sipe 20 is preferably 1/5 to 1/3 of the length L1 of the recess 10 in the tire circumferential direction. As a result, the above-described effects are exhibited more effectively.

In this embodiment, one recess 10 is formed in each of the first block wall 7 and the second block wall 8, but the present invention is not limited to this embodiment, and for example, a plurality of recesses 10 may be provided. can be Also in this case, when a plurality of sipes 15 are provided in the first block 3 , it is desirable that each sipe 15 extends without crossing each recess 10 . Moreover, it is desirable that the lateral groove 5 is closest to the sipe 15 having the shortest length in the tire axial direction among the sipes 15 .

The first sipe 15A may be formed so as to extend from the first block wall 7 and line up two or more in the tire circumferential direction. In this case, it is desirable that the distance L9 in the tire circumferential direction between the first sipes 15A, 15A adjacent in the tire circumferential direction satisfies the following formula (1). n is the number of first sipes 15A. Similarly to the first sipe 15A, when two or more second sipes 15B are arranged in the tire circumferential direction from the second block wall 8, it is desirable to satisfy the following formula (1).
La/n<L9<La/(n+1) (1)

FIG. 6 is a development view of the entire tread portion 2 of another embodiment. Components of this embodiment that are the same as those of the present embodiment shown in FIG. As shown in FIG. 6, the tread portion 2 of this embodiment is provided with a pair of crown main grooves 31, 31 and a pair of shoulder main grooves 32, 32. As shown in FIG. The crown main groove 31 is arranged outside the tire equator C and continuously extends in the tire circumferential direction. The shoulder main groove 32 is arranged outside the crown main groove 31 in the tire axial direction and extends continuously in the tire circumferential direction.

Further, the tread portion 2 of this embodiment is provided with a plurality of crown lateral grooves 33, middle lateral grooves 34, and shoulder lateral grooves 35, respectively. The crown lateral groove 33 connects between the pair of crown main grooves 31, 31 in this embodiment. The middle lateral groove 34 connects between the crown main groove 31 and the shoulder main groove 32 in this embodiment. In this embodiment, the shoulder lateral groove 35 connects the shoulder main groove 32 and the tread edge Te.

Due to the main grooves 31 and 32 and the lateral grooves 33 to 35, the tread portion 2 is provided with a plurality of crown blocks 36, middle blocks 37 and shoulder blocks 38, respectively. The crown block 36 is divided by a pair of crown main grooves 31 , 31 and crown lateral grooves 33 . The middle block 37 is divided by the crown main groove 31 , the shoulder main groove 32 and the middle lateral groove 34 . The shoulder block 38 is divided by the shoulder main groove 32 , the tread edge Te and the shoulder lateral groove 35 .

In this embodiment, the crown block 36 has a pair of crown circumferential walls 36e, 36e extending in the tire circumferential direction on both sides in the tire axial direction. In this embodiment, the middle block 37 has a middle first wall 37e extending in the tire circumferential direction on the crown block 36 side and a middle second wall 37i extending in the tire circumferential direction on the shoulder block 38 side. In this embodiment, the shoulder block 38 has a shoulder circumferential wall 38e extending in the tire circumferential direction on the middle block 37 side.

In this embodiment, the pair of crown circumferential walls 36 e , 36 e are provided with recesses 40 that are recessed inside the crown block 36 . The first middle wall 37e and the second middle wall 37i are provided with recesses 41 and 42 that are recessed inside the middle block 37, respectively. A recess 43 recessed inside the shoulder block 38 is provided in the shoulder circumferential wall 38e.

In this embodiment, the crown block 36, the middle block 37 and the middle lateral groove 34 respectively correspond to the first block 3, the second block 4 and the lateral groove 5 in the embodiment of FIG. referred to as "the first aspect"). Also, from a different point of view, in this embodiment, the middle block 37, crown block 36 and crown lateral groove 33 correspond to the first block 3, second block 4 and lateral groove 5 of the embodiment of FIG. , for convenience, this aspect will be referred to as a “second aspect”). In the first mode, the recess 40 provided in the crown circumferential wall 36e overlaps the opening 34A of the middle lateral groove 34 on the crown block 36 side in the tire circumferential direction. In the second mode, the recess 41 provided in the middle first wall 37e overlaps the opening 33A of the crown lateral groove 33 on the middle block 37 side in the tire circumferential direction.

As described above, in this embodiment, the snow flowing from the crown lateral groove 33 and the middle lateral groove 34 flows into two places, the recessed portion 40 of the crown block 36 and the recessed portion 41 of the middle block 37, during left or right turning on a snowy road. It is caught by and forms a solid snow mass.

The crown lateral groove 33 and middle lateral groove 34 include a pair of outer portions 45, 45 and a central portion 46 in this embodiment. In this embodiment, the outer portions 45 are inclined with respect to the tire axial direction, and are arranged on both longitudinal sides of the lateral grooves 33 and 34 . The central portion 46 joins the outer portions 45 , 45 and is inclined at a larger angle than the outer portion 45 with respect to the tire axial direction. Since the central portion 46 has a large circumferential component, it suppresses sideslip during turning. The outer portion 45 has a large axial component, thus facilitating snow evacuation during turns. In this embodiment, the crown lateral grooves 33 and the middle lateral grooves 34 are inclined in the same direction with respect to the tire axial direction (upward to the right in the figure).

FIG. 7 is a developed view of the tread portion 2 of the same embodiment as in FIG. As shown in FIG. 7, in this embodiment, each of the crown block 36, the middle block 37 and the shoulder blocks 38 is provided with a sipe 15. As shown in FIG. Sipes 15 extend from crown circumferential wall 36e, middle first wall 37e, middle second wall 37i, and shoulder circumferential wall 38e toward the interior of respective blocks 36-38 in this embodiment.

The sipes 15 of the crown block 36 and the middle block 37 include first sipes 15A and second sipes 15B in this embodiment. First sipe 15A includes, for example, first short sipe 16 and first long sipe 17 . Second sipe 15B includes, for example, second short sipe 19 and second long sipe 20 .

In this embodiment, the first short sipe 16 and the first portion 22 of the first sipe 15A of the crown block 36 and the middle block 37 extend in a zigzag shape, and the second portion 23 extends in a straight line. . The second sipes 15B of the crown block 36 and the middle block 37 are formed similarly to the first sipes 15A. Therefore, description of the second Sipe 15B of this embodiment is omitted.

The first sipe 15A of this embodiment extends across the recess 10 . In such a case, the rigidity of the portion of the first block 3 near the recess 10 where the first sipe 15A is provided is reduced. However, in this embodiment, the first short sipe 16 and the first portion 22 extending from the recess 10 extend in a zigzag pattern. Therefore, even if a lateral force is applied to the blocks 36, 37, the sipe walls mesh with each other to suppress axial deformation of the recesses 10 of the blocks 36, 37. Since it can firmly catch the snow that flows, it maintains high performance on snowy roads. In this embodiment, the first short sipe 16 and the first portion 22 are positioned close to the connection position between the axial portion 13 and the circumferential portion 14, that is, the first short sipe 16 and the first portion 22 are positioned relative to each other. are arranged at relatively spaced apart positions.

In this embodiment, the sipes 15 arranged in the crown block 36 and the middle block 37 are arranged symmetrically at any point on the tread surface of each block 36 , 37 .

An imaginary groove edge Vn obtained by extending the groove edge 34 e of the middle lateral groove 34 toward the shoulder block 38 intersects the recessed portion 10 of the shoulder block 38 . As a result, a strong snow mass is formed in the concave portion 10 of the shoulder block 38 as well, utilizing the lateral force during turning. In this embodiment, only one of the imaginary groove edges Vn of the middle lateral groove 34 crosses the recess 10 of the shoulder block 38 . It should be noted that the present invention is not limited to such a mode, and both imaginary groove edges Vn of the middle lateral groove 34 may intersect with the recessed portion 10 of the shoulder block 38 .

Although the embodiments of the present invention have been described in detail above, it is needless to say that the present invention is not limited to the illustrated embodiments, and can be implemented in various modifications.

A passenger car pneumatic tire of size 265/70R17 having the basic pattern shown in FIG. The main common specifications and test methods for each sample tire are as follows.
"A" in Table 1 is an embodiment in which each short sipe and each long sipe are shown in FIG.
"B" is the embodiment in which each short sipe and each long sipe are shown in FIG. again,
"C" in Table 1 is an embodiment in which the first short sipe and the first long sipe are shown in FIG.
"D" is an aspect in which the first short sipe is located at the base farther from the lateral groove than the first long sipe.

<Snow road performance / wear resistance performance>
Each test tire was installed on the following test vehicle, and the test driver ran the test course on snow and dry asphalt roads. At this time, snow road performance related to stability during cornering and wear resistance performance related to the occurrence of wear were evaluated by test drivers. The results are displayed as a score with the value of Comparative Example 1 being 50. Various performances are excellent, so that a numerical value is large.
Mounting rim: 17×7.5JJ
Tire internal pressure: 240kPa
Tire mounting position: All wheels Test vehicle: Table 1 shows the test results of a four-wheel drive vehicle with a displacement of 4300 cc.

As a result of the test, it was confirmed that the tire of the example had improved snow road performance while maintaining the wear resistance performance as compared with the tire of the comparative example.

1 Tire 2 Tread Part 3 First Block 4 Second Block 5 Lateral Groove 5A Opening 7 First Block Wall 7c Intermediate Position 10 Recess 10c Intermediate Position

Claims (9)

being a tire
The tread portion is provided with a first block, a second block adjacent to the first block in the tire axial direction and arranged in the tire circumferential direction, and a lateral groove extending between the second blocks adjacent in the tire circumferential direction,
The first block has a first block wall extending in the tire circumferential direction on the side of the lateral groove,
The first block wall is provided with a recess that is recessed inside the first block,
The recess overlaps an opening of the lateral groove on the side of the first block in the tire circumferential direction,
The length of the recess in the tire circumferential direction is 30% to 70% of the length of the first block wall in the tire circumferential direction,
The distance in the tire circumferential direction between the intermediate position of the recess in the tire circumferential direction and the intermediate position of the first block wall in the tire circumferential direction is 10% or less of the length of the first block wall in the tire circumferential direction. and
The first block is provided with a sipe,
The sipe includes a first sipe extending from the first block wall and discontinued before an axially intermediate position of the first block,
The first sipe extends without crossing the recess,
The first sipe includes a first short sipe and a first long sipe having a greater length in the tire axial direction than the first short sipe,
The distance between the first short sipe and the intermediate position of the opening in the tire circumferential direction is the distance between the first long sipe and the intermediate position of the opening in the tire circumferential direction. less than
tire. The tire according to claim 1, wherein the first short sipe is spaced from the first long sipe via the recess in the tire circumferential direction . The first block has a second block wall arranged on the opposite side in the tire axial direction from the first block wall,
the sipe includes a second long sipe extending from the second block wall and terminating before the intermediate position of the first block;
3. The distance between the end of the first long sipe and the end of the second long sipe is 1/5 to 1/3 of the length of the recess in the tire circumferential direction. tire. The first long sipe has a first portion that extends parallel to the first short sipe, a second portion that extends toward the center of the first block, and a bend that connects the first portion and the second portion. including bends that
The tire according to any one of claims 1 to 3 , wherein the bent portion is provided with a tie bar having a raised sipe bottom . being a tire
The tread portion is provided with a first block, a second block adjacent to the first block in the tire axial direction and arranged in the tire circumferential direction, and a lateral groove extending between the second blocks adjacent in the tire circumferential direction,
The first block has a first block wall extending in the tire circumferential direction on the side of the lateral groove,
The first block wall is provided with a recess that is recessed inside the first block,
The recess overlaps an opening of the lateral groove on the side of the first block in the tire circumferential direction,
The length of the recess in the tire circumferential direction is 30% to 70% of the length of the first block wall in the tire circumferential direction,
The distance in the tire circumferential direction between the intermediate position of the recess in the tire circumferential direction and the intermediate position of the first block wall in the tire circumferential direction is 10% or less of the length of the first block wall in the tire circumferential direction. and
The first block is provided with a sipe,
The sipe includes a first sipe extending from the first block wall and discontinued before an axially intermediate position of the first block,
The sipe includes a plurality of first sipes extending from the first block wall and arranged in a circumferential direction of the tire,
A circumferential distance L9 between adjacent first sipes in the tire circumferential direction satisfies the following formula (1):
tire.
La/n<L9<La/(n+1) (1)
However, n is the number of the first sipes. being a tire
The tread portion is provided with a first block, a second block adjacent to the first block in the tire axial direction and arranged in the tire circumferential direction, and a lateral groove extending between the second blocks adjacent in the tire circumferential direction,
The first block has a first block wall extending in the tire circumferential direction on the side of the lateral groove,
The first block wall is provided with a recess that is recessed inside the first block,
The recess overlaps an opening of the lateral groove on the side of the first block in the tire circumferential direction,
The length of the recess in the tire circumferential direction is 30% to 70% of the length of the first block wall in the tire circumferential direction,
The distance in the tire circumferential direction between the intermediate position of the recess in the tire circumferential direction and the intermediate position of the first block wall in the tire circumferential direction is 10% or less of the length of the first block wall in the tire circumferential direction. and
The recess includes a pair of axial portions extending from the first block wall and spaced apart in the tire circumferential direction, and a circumferential portion joining the pair of axial portions,
The length of the pair of axial portions in the tire axial direction is 5% to 11% of the length of the circumferential portion in the tire circumferential direction,
tire. The tire according to any one of claims 1 to 6 , wherein the concave portion has a rectangular shape in a plan view of the tread portion . The tire according to claim 7 , wherein the recess is tapered toward the inside of the first block in a plan view of the tread portion . 4. A distance in the tire circumferential direction between an intermediate position of the opening in the tire circumferential direction and an intermediate position of the recess in the tire circumferential direction is 40% or less of a length of the recess in the tire circumferential direction. 9. Tire according to any one of 1 to 8.

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