JP6952593B2 - tire - Google Patents

Description

The present invention relates to a tire having a shoulder block on the tread portion.

As a result of restrictions on the use of spiked tires having spikes or studs protruding from the surface of the tread portion, tires having improved performance on ice and snow without providing them (so-called studless tires) have become widespread.

As a tread pattern for such a studless tire, a plurality of land rows are formed by a plurality of main grooves extending in the tire circumferential direction, and a plurality of lug grooves or the like are provided in the land rows to divide the blocks into blocks. Block patterns that form various types of tires are widely used. In this block pattern, a plurality of blocks and sipes are formed on the surface of the tread portion to increase the edge amount (length) and enhance the edge effect, so that the traction performance and the braking performance on the ice and snow road surface are on ice and snow. It has improved performance.

FIG. 5 shows a plan view of the tire tread pattern described in Patent Document 1 as an example of the block pattern. In this tread pattern, four main grooves 110 and 111 extending in the tire circumferential direction, and among those main grooves, the outermost main groove (hereinafter referred to as shoulder main groove) 111 in the tire width direction and the tread end TE A shoulder block row 130 composed of a plurality of shoulder blocks 131 formed by partitioning the first lug groove 121 and the second lug groove 122 is provided.

FIG. 6 shows the shoulder block 131 and its vicinity in FIG. As shown in the figure, the first lug groove 121 has a portion having a relatively narrow width w10 extending from the shoulder main groove 111 side in the direction of the tread end TE (hereinafter referred to as the first portion), and the tread end TE having a large width w11. It has a relatively wide portion (hereinafter referred to as a second portion) that is open.

By providing a wide portion at the tread end TE in this way, it is possible to insert a chain when attaching a tire chain (hereinafter referred to as a chain) during snowfall. Further, by making the width (length in the tire circumferential direction) w10 of the first portion wider than the width of the chain corresponding to the tire, the chain slip resistance that makes it difficult for the mounted chain to slip during running is ensured. That is, when the chain enters the first lug groove 121, the chain becomes difficult to move with respect to the input when the vehicle is running.

On the other hand, if a lug groove having a large opening at the tread end TE is arranged in the shoulder block, the rigidity of the shoulder block is lowered, which causes an increase in deformation of the low rigidity block at the time of side force input. That is, the chain slip resistance and the uneven wear resistance are in conflict.

Here, the chain displacement resistance can be improved by the relationship between the phase of the tread pattern (position in the tire circumferential direction) and the shape of the chain. That is, for example, in a general chain for trucks and buses, as shown in FIG. 5, a ladder in which chains 202 cross at regular intervals in the width direction with respect to two chains 201 parallel to each other in the circumferential direction. It is formed in a mold. Therefore, by aligning the phases of the lug grooves (here, the first lug groove 121) that divide the shoulder blocks 131 on both sides in the tire width direction in the tire circumferential direction, the entire chain is firmly bitten into the tire and the chain shift is suppressed. can.

However, if the phases of the first lug grooves 121 in the shoulder blocks 131 on both sides in the tire width direction are aligned in the tire circumferential direction, workability when the chain is attached to the tire deteriorates. That is, when attaching a chain to a tire, the chain is usually laid on the ground near the front of the tire in a stretched state, the vehicle is slightly moved to the chain side, the tire is placed on one end side of the chain, and then the chain The other end side is wound around the upper part of the tire, and finally the chain is squeezed (tightened) and inserted into the first lug groove 121. At the time of this winding, the chain 202 may be caught in the first lug groove 121.

Japanese Unexamined Patent Publication No. 2008-12336

The present invention has been made to solve such a problem, and an object of the present invention is to ensure chain displacement resistance and chain mounting workability and bias resistance in a tire having a shoulder block in a tread portion. It is to improve the wear resistance.

The present invention comprises a plurality of main grooves extending in the tire circumferential direction and a plurality of shoulder blocks arranged in the tire circumferential direction by a plurality of lug grooves connecting the outermost main groove in the tire width direction and the tread end. A tire provided on a tread portion, the lug groove has a wide end portion due to a notch at a corner portion on the tread end side of the shoulder block, and the shoulder block has a width direction groove extending in the tire width direction. , The width of the wide end portion is equal to or larger than the wire diameter of the predetermined chain to be mounted, and the width of the portion other than the wide end portion is less than the wire diameter. the width of the groove, Ri width der following portions other than the wide end, out of phase on both sides of the lug grooves of the tire equatorial plane, a tire.
Further, the present invention includes a plurality of main grooves extending in the tire circumferential direction and a plurality of shoulder blocks arranged in the tire circumferential direction by a plurality of lug grooves connecting the outermost main groove in the tire width direction and the tread end. The lug groove has a wide end portion due to a notch at a corner on the tread end side of the shoulder block, and the shoulder block extends in the width direction of the tire. It is partitioned in the tire circumferential direction by a groove, the width of the wide end portion is equal to or larger than the wire diameter of the predetermined chain to be mounted, and the width of the portion other than the wide end portion is less than the wire diameter. The width of the groove in the width direction is equal to or less than the width of the portion other than the wide end portion, the shoulder block is partitioned in the tire width direction by the circumferential groove extending in the tire circumferential direction, and the width direction groove is defined by the tire width direction. A tire having different phases on both sides of the circumferential groove.

According to the present invention, in a tire having a shoulder block in the tread portion, it is possible to improve the workability and uneven wear resistance of chain mounting while ensuring the chain slip resistance.

It is a top view which shows the tread pattern of the tire which concerns on 1st Embodiment of this invention. It is an enlarged plan view of the shoulder block in FIG. It is a perspective view which looked at the shoulder block in FIG. 1 from the tread end side. It is a top view which shows the tread pattern of the tire which concerns on 2nd Embodiment of this invention. It is a top view which shows the tread pattern of a conventional tire. It is a figure which shows the shoulder block in FIG. 5 and its vicinity.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The tire according to the embodiment of the present invention is a pneumatic tire for a vehicle (for example, a heavy load tire, a passenger vehicle tire), and is formed into a well-known structure by general tire components. That is, the tire is a pair of bead portions, a pair of sidewall portions located outside the tire radius of the pair of bead portions, a tread portion in contact with the road surface, and a pair of tires located between the tread portion and the pair of sidewall portions. It has a shoulder part. Further, the tire includes a pair of bead cores, a carcass arranged between the pair of bead cores, a belt arranged on the outer peripheral side of the carcass, and a tread rubber having a predetermined tread pattern.

[First Embodiment]
<Tread pattern>
FIG. 1 is a plan view showing a tread pattern of a tire according to the first embodiment of the present invention, and schematically shows a part of the tread portion in the tire circumferential direction.

The tire according to the present embodiment is a studless tire (275 / 80R22.5) for trucks and buses used on ice and snow road surfaces, and the tread pattern thereof is a block pattern having a plurality of blocks.

As shown in the figure, this tire is provided with a plurality of (here, four) main grooves 10 and 11 extending in the tire circumferential direction S in the tread portion 1, and the tire circumferential direction is provided by these main grooves and the tread end TE. Five rows of land rows 30, 40, and 50 extending to S are formed.

Further, this tire is provided with a plurality of lug grooves 20, 21 and 22 arranged in the land rows 30, 40 and 50 extending in the tire width direction H, and the lug grooves thereof make each land row 30 30. , 40, 50 are divided into a plurality of blocks 31, 41, 51 arranged in the tire circumferential direction S.

The main grooves 10 are two main grooves arranged on the innermost side (the tire equatorial plane E side) in the tire width direction H with the tire equatorial plane E in between, and the main grooves 11 are in the tire width direction of the main groove 10. Two main grooves 11 arranged outside the H. Hereinafter, the main groove 10 and the main groove 11 will be referred to as a central side main groove 10 and a shoulder main groove 11, respectively.

The land row 30 is a land row located on the tire equatorial plane E arranged between the two central main grooves 10. Further, the land row 40 is two rows of land rows arranged between the central main groove 10 and the shoulder main groove 11. Further, the land row 50 is two rows of land rows located between the shoulder main groove 11 and the tread end TE and located on the outermost side (shoulder side) in the tire width direction H. Hereinafter, the land rows 30, 40, and 50 will be referred to as a central land row 30, an intermediate land row 40, and a shoulder land row 50, respectively.

The central land row 30 is partitioned in the tire width direction H by a dividing groove 12 extending in a zigzag shape in the tire circumferential direction S. Further, the central land row 30 is partitioned in the tire circumferential direction S by the lug groove 20 described above, and is partitioned into a plurality of blocks 31 by the dividing groove 12 and the lug groove 20. The block 31 has a sipe 32 extending in a zigzag shape in the tire width direction S.

The intermediate land row 40 is partitioned in the tire width direction H by a dividing groove 13 extending in a zigzag shape in the tire circumferential direction S. Further, the intermediate land row 40 is partitioned in the tire circumferential direction S by the lug groove 21 described above, and is partitioned into a plurality of blocks 41 by the dividing groove 13 and the lug groove 21. The block 41 has a sipe 42 extending in a zigzag shape in the tire width direction S.

The shoulder land row 50 is divided into a plurality of blocks 51 in the tire circumferential direction S by a lug groove 22 penetrating from the shoulder main groove 11 to the tread end TE described above. One block 51 on the left side of the tire equatorial plane E in the figure is shaded. Hereinafter, the block 51 is referred to as a shoulder block 51. Details of the lug groove 22 and the shoulder block 51 will be described later.

<Details of lug groove and shoulder block>
FIG. 2 is an enlarged plan view of the shoulder block in FIG. 1, and FIG. 3 is a perspective view of the shoulder block in FIG. 1 as viewed from the tread end side.

As shown in FIGS. 2 and 3, the shoulder block 51 has first to fourth grooves 51e extending linearly in the tire circumferential direction S and widthwise grooves 51f extending linearly in the tire width direction H. It is divided into four sub-blocks consisting of sub-blocks 51a to 51d. Here, the depth of the width direction groove 51f is 12 mm, which is the same as the depth of the lug groove 22, and the depth of the circumferential groove 51e is 2 mm.

The block shown in FIG. 2 corresponds to the shoulder block shaded in FIG. 1. However, for convenience, the plan-view shapes of the second subblock 51b and the third subblock 51c have been changed from the parallelogram in FIG. 1 to a rectangle, and the widthwise groove 51f has been changed from a polygonal line to a straight line. Of course, as a modification, a tread pattern in which the shoulder block 51 in FIG. 1 has the shape shown in FIG. 2 can also be configured.

In the present embodiment, the shoulder main groove 11, the lug groove 22, and the shoulder block 51 have the following features (i) to (vi).

(i) As described above, the lug groove 22 penetrates from the shoulder main groove 11 to the tread end TE. The depth of the lug groove 22 is more than half the depth of the shoulder main groove 11. In the present embodiment, the depth of the shoulder main groove 11 is 20 mm, and the depth of the lug groove 22 is 12 mm.

(ii) The lug groove 22 forms a notch at a portion extending from the shoulder main groove 11 with a constant width (hereinafter referred to as a base portion) and at the corners of the first subblock 51a and the fourth subblock 51d, and forms a notch at the tread end TE. It has a wide end that is open. The width of the base (length in the tire circumferential direction) w1 is 6.9 mm, which is an example of less than 7.0 mm, which is the wire diameter of the chain corresponding to the tire (275 / 80R22.5) according to the present embodiment. By making the width w1 of the base portion of the lug groove 22 smaller than the wire diameter of the chain to be mounted in this way, catching when the chain is wound around the tire is prevented, so that workability is improved.

Here, the wire diameter of the chain that matches the size of the tire will be described. Commercially available chains have one or more wire diameters corresponding to each size of tire to be mounted. Therefore, in the tire (275 / 80R22.5) according to the present embodiment, the width w1 of the base portion of the lug groove 22 is set to 6.9 mm, which is less than 7.0 mm, which is the thinnest wire diameter of the chain corresponding to the tire. For tires of smaller size, the wire diameter of the compatible chain is also smaller, so the width of the base of the lug groove is narrowed according to the wire diameter.

(iii) The width of the wide end portion of the lug groove 22 extends from the start point (inner end in the tire width direction: 51i, 51k described later) to the end point (intersection with the tread end TE: 51j, 51l described later). The width w2 at the end point is wider than the wire diameter of the chain. Preferably, w2 is set to about the width of the chain (wire diameter x 2 + wire spacing) or less. Further, the ratio of the tire circumferential length of the notch to the tire circumferential length L1 (see FIG. 1) of the shoulder block 51 is set to 50% or less. By providing the wide end portion in this way, it is possible to put the chain in the desired wide end portion when the chain is wound around the tire and then squeezed like a conventional tire. Further, since the chain is maintained in the wide end portion even when the vehicle is running, it is possible to secure the chain displacement resistance when the vehicle is running.

(iv) The phase difference L2 (see FIG. 1) of the lug grooves 22 on both sides of the tire equatorial plane E is 50% or less, preferably 15% or more and 35% or less of the tire circumferential length L1 of the shoulder block 51. If it is less than 15%, the phase difference is small, so that the effect of preventing catching when the chain is wound is reduced. If it exceeds 35%, the phase difference between the shoulder block 51 adjacent to the tire peripheral direction and the lug groove 22 becomes small, and the effect of preventing the chain from being caught is reduced.

(v) The start point and end point of the notch do not contact the circumferential groove 51e and the width direction groove 51f. That is, in the case of FIGS. 2 and 3, the notch start points 51i and 51k do not touch the circumferential groove 51e, and the notch end points 51j and 51l do not touch the width direction groove 51f.

(vi) Starting from the intersection of the circumferential groove 51e and the width direction groove 51f, the tire circumferential direction S is formed on both sides, the tire width direction H is formed only on the tread end TE side, and grooves 51g and 51h deeper than the other parts are formed. Has been done. The tire circumferential length of the groove 51g is 50% or less of the tire circumferential length of the shoulder block 51, and the tire width direction length of the groove 51h is 50% or less of the tire width direction length of the shoulder block 51.

Here, the shoulder block 51 is divided into four sub-blocks including the first to fourth sub-blocks 51a to 51d by the circumferential groove 51e and the width-direction groove 51f, and (v) and (vi). The effect obtained by the configuration will be described. With these configurations, the following effects a to c can be obtained.

a: Since the shoulder block 51 is provided with the width direction groove 51f, when the chain is wound around the tire and then squeezed, both ends of the sub block sandwiching the lug groove 22 in the tire circumferential direction are pressed by the chain to form the width direction groove. By deforming in the direction of 51f, the lug groove 22 expands and the chain enters. By maintaining this entry state even when the vehicle is running, chain slip resistance is ensured.

b: Since the shoulder block 51 is provided with the groove 51f in the width direction, the movement of the shoulder block 51 is divided in the tire circumferential direction. Therefore, the deformation difference of the stepping kick is suppressed, and the heel / toe wear is suppressed. Further, since the circumferential groove 51e and the width direction groove 51f are provided, the first subblock 51a and the fourth subblock 51d are deformed in the directions of P2 and P1 respectively when the vehicle is running, so that uneven wear resistance is obtained. Can be improved.

c: By arranging the circumferential groove 51e closed in the shoulder block 51 and the grooves 51g and 51h deeper than the width direction groove 51f, the shoulder block 51 can be easily moved when the chain is inserted into the lug groove 22, so that the shoulder block 51 can be fitted. Since it is easy to fit, the workability of attaching the chain is improved.

Further, as shown in FIG. 3, the corners of the first subblock 51a and the fourth subblock 51d, that is, the corners of the first subblock 51a and the fourth subblock 51d formed by the notches. The side walls 51m and 51n are preferably tilted by a predetermined angle (0 ° to 20 °) from the direction perpendicular to the bottom surface of the lug groove 22. By setting this range, the workability of attaching the chain to the lug groove 22 can be improved. If it is larger than 20 °, it may get caught in the lug groove 22 when the chain is wound and the workability may be deteriorated, which is not preferable.

As described in detail above, according to the tire according to the present embodiment, it is possible to improve the workability and uneven wear resistance of chain mounting while ensuring the chain slip resistance.

[Second Embodiment]
<Tread pattern>
FIG. 4 is a plan view showing a tread pattern of a tire according to a second embodiment of the present invention, and schematically shows a part of the tire circumferential direction S of the tread portion.

Similar to the first embodiment, the tire according to the present embodiment is also a studless tire (275 / 80R22.5) for trucks and buses used on ice and snow road surfaces, and its tread pattern is a block having a plurality of blocks. It is a pattern.

As shown in the figure, this tire is provided with a plurality of (here, four) main grooves 60 and 61 extending in the tire circumferential direction S in the tread portion 2, and the tire circumferential direction is provided by these main grooves and the tread end TE. Five rows of land rows 80, 90, and 100 extending to S are formed.

Further, this tire is provided with a plurality of lug grooves 70, 71, 72, 73 arranged in the land rows 80, 90, 100 and extending in the tire width direction H, and each land portion is provided with these lug grooves. Rows 80, 90, 100 are divided into a plurality of blocks 81, 91, 101 arranged in the tire circumferential direction S.

The main grooves 60 are two main grooves arranged on the innermost side (the tire equatorial plane E side) in the tire width direction H with the tire equatorial plane E in between, and the main grooves 61 are in the tire width direction of the main groove 60. Two main grooves 61 arranged outside the H. Hereinafter, the main groove 60 and the main groove 61 will be referred to as a central side main groove 60 and a shoulder main groove 61, respectively.

The land row 80 is a land row located on the tire equatorial plane E arranged between the two central main grooves 60. Further, the land row 90 is a two row of land rows arranged between the central main groove 60 and the shoulder main groove 61. Further, the land row 100 is two rows of land rows located between the shoulder main groove 61 and the tread end TE and located on the outermost side (shoulder side) in the tire width direction H. Hereinafter, the land row 80, 90, and 100 will be referred to as a central land row 80, an intermediate land row 90, and a shoulder land row 100, respectively.

The central land row 80 is partitioned in the tire width direction H by a dividing groove 62 extending in a zigzag shape in the tire circumferential direction S. Further, the central land row 80 is partitioned in the tire circumferential direction S by the lug groove 70 described above, and is partitioned into a plurality of blocks 81 by the dividing groove 62 and the lug groove 70. The block 81 has a sipe 82 extending in a zigzag shape in the tire width direction S.

The intermediate land row 90 is divided into a plurality of blocks 91 by the lug groove 71 described above. The block 91 has a sipe 92 extending in a zigzag shape in the tire width direction S.

The shoulder land row 100 is partitioned in the tire width direction H by a dividing groove (circumferential groove) 63 extending in the tire circumferential direction. Further, the shoulder land row 100 is divided into a plurality of blocks 101 by the lug grooves 72 and 73 described above. Hereinafter, the block 101 is referred to as a shoulder block 101.

The shoulder block 101 is composed of the width direction groove 101e connecting the shoulder main groove 61 and the dividing groove 63, the width direction groove 101f connecting the dividing groove 63 and the tread end TE, and the dividing groove 63, and the first to fourth subblocks. It is divided into 101a to 101d. Here, the width of the width direction groove 101e and the width direction groove 101f is equal to or less than the width of the lug groove 73.

Further, the phases of the width direction groove 101e and the width direction groove 101f are different. It is preferable that the phase shift of the shoulder block 101 with respect to the tire circumferential length is 15% or more and 35% or less. By setting this range, the effect of preventing catching on the widthwise grooves 101e and 101f when the chain is wound is enhanced. If it is out of this range, the effect is reduced, which is not preferable.

Further, the phases of the widthwise grooves 101f on both sides of the tire equatorial plane E are also out of phase. It is preferable that the phase shift of the shoulder block 101 with respect to the tire circumferential length is 15% or more and 35% or less. By setting this range, the effect of preventing the chain from being caught in the groove 101f in the width direction when the chain is wound is enhanced. If it is out of this range, the effect is reduced, which is not preferable.

Of the lug grooves 72 and lug grooves 73 that partition the shoulder block 101, the lug grooves 73 on the outer side in the tire width direction are a portion (hereinafter referred to as a base) extending with a constant width from the dividing groove 63, and the second subblock 101b and the third. It has a notch at the corner of the subblock 101c and a wide end that is open to the tread end TE. The width of the base is the same as the base of the lug groove 22 in the first embodiment, and is an example of less than 7.0 mm, which is the wire diameter of the chain suitable for the tire (275 / 80R22.5) according to the present embodiment. It is 6.7 mm. By making the width of the base of the lug groove 73 smaller than the wire diameter of the chain to be mounted in this way, it is possible to prevent the chain from being caught when the chain is wound around the tire, as in the first embodiment. Is improved.

Similar to the wide end portion of the lug groove 22 in the first embodiment, the width of the wide end portion of the lug groove 73 increases linearly from the start point to the end point of the notch, and the width of the end point increases in a chain. Wider than the wire diameter of. By providing the wide end portion in this way, it is possible to put the chain in the desired wide end portion when the chain is wound around the tire and then squeezed as in the first embodiment. Further, since the chain is maintained in the wide end portion even when the vehicle is running, it is possible to secure the chain displacement resistance when the vehicle is running.

Of the lug grooves 72 and lug grooves 73 that partition the shoulder block 101, the width of the lug groove 72 on the inner side of the tire width is equal to or less than the width of the base of the lug groove 73 (6.7 mm). It is possible to prevent the tire from getting caught when it is wrapped around the tire.

Of the four subblocks constituting the shoulder block 101, the second subblock 101b and the third subblock 101c on the TE side of the tread end are partitioned by the width direction groove 101f, so that after the chain is wound around the tire. When the tires are squeezed, the ends of the second subblock 101b and the third subblock 101c in the tire circumferential direction are pressed by the chain and deformed in the tire circumferential direction, so that the lug groove 73 expands and the chain enters. By maintaining this entry state even when the vehicle is running, chain slip resistance is ensured.

Further, since the movements of the second sub-block 101b and the third sub-block 101c on the outer side in the tire width direction of the shoulder block 101 in the tire circumferential direction are separated by the width direction groove 101f, the deformation difference of the treading kick is suppressed, and the heel / Toe wear leads to suppression.

The phase difference between the lug grooves 73 on both sides of the tire equatorial plane E is 50% or less, preferably 15% or more and 35% or less of the tire circumferential length of the shoulder block 101. If it is less than 15%, the phase difference is small, so that the effect of preventing catching when the chain is wound is reduced. If it exceeds 35%, the phase difference between the shoulder block 101 adjacent to the tire peripheral direction and the lug groove 73 becomes small, and the effect of preventing catching when the chain is wound is reduced.

As described in detail above, according to the tire according to the present embodiment, it is possible to improve the workability of chain mounting while ensuring the chain slip resistance.

10,11,60,61 ... Main groove, 20-22,70-73 ... Lag groove, 51,101 ... Shoulder block, 51e ... Circumferential groove, 51f, 101e, 101f ... Width groove, E ... Tire equatorial plane , TE ... Tread edge.

Claims (7)

The tread portion is provided with a plurality of main grooves extending in the tire circumferential direction and a plurality of shoulder blocks arranged in the tire circumferential direction by a plurality of lug grooves connecting the outermost main groove in the tire width direction and the tread end. Tires
The lug groove has a wide end due to a notch at the corner of the shoulder block on the tread end side.
The shoulder block is partitioned in the tire circumferential direction by a width direction groove extending in the tire width direction.
The width of the wide end portion is equal to or larger than the wire diameter of the predetermined chain to be mounted, the width of the portion other than the wide end portion is less than the wire diameter, and the width of the groove in the width direction is other than the wide end portion. der following parts of the width is,
Tire A tire whose lug grooves on both sides of the equatorial plane are out of phase . In the tire according to claim 1,
A tire having a phase shift of 15% or more and 35% or less of the tire circumferential length of the shoulder block . The tread portion is provided with a plurality of main grooves extending in the tire circumferential direction and a plurality of shoulder blocks arranged in the tire circumferential direction by a plurality of lug grooves connecting the outermost main groove in the tire width direction and the tread end. Tires
The lug groove has a wide end portion due to a notch at a corner portion on the tread end side of the shoulder block.
The shoulder block is partitioned in the tire circumferential direction by a width direction groove extending in the tire width direction.
The width of the wide end portion is equal to or larger than the wire diameter of the predetermined chain to be mounted, the width of the portion other than the wide end portion is less than the wire diameter, and the width of the groove in the width direction is other than the wide end portion. Is less than or equal to the width of the part
The shoulder block is partitioned in the tire width direction by a circumferential groove extending in the tire circumferential direction.
A tire in which the widthwise grooves have different phases on both sides of the circumferential groove. In the tire according to claim 3,
Of the widthwise grooves, the phase of the widthwise groove on the outer side in the tire width direction is different on both sides of the tire equatorial plane . In the tire according to claim 1 or 3.
A tire in which the ratio of the tire circumferential length of the notch to the tire circumferential length of the shoulder block is 50% or less . In the tire according to claim 1,
The shoulder block is a tire divided in the tire width direction by a circumferential groove extending in the tire circumferential direction . In the tire according to claim 1 or 3.
A tire in which the side wall of the notch is inclined by 0 ° or more and 20 ° or less from a direction perpendicular to the bottom surface of the lug groove.

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