JP2022019563A - tire - Google Patents

Abstract

To provide a tire that is able to achieve both the cut resistance performance and mud drainage performance of a side wall.SOLUTION: A tire includes a tread 13 and a pair of side walls 12, and at least one of the pair of side walls 12 has a plurality of side blocks projecting from a side-wall reference surface. The plurality of side blocks includes first side blocks 2 and second side blocks 3 alternately arranged at intervals in a tire circumferential direction. Each first side block 2 has a groove 23 extending into a block from a side surface facing an adjacent second side block 3. Each second side block 3 has an inclined surface 35c whose height from the reference surface becomes lower toward adjacent first side block 2, and the inclined surface 35c extends into the groove 23 of the adjacent first side block 2.SELECTED DRAWING: Figure 2

Description

The present disclosure relates to tires, in particular to improvements in side blocks provided on the sidewalls of the tire.

Conventionally, a tire is known in which a sidewall is provided with a first protruding portion protruding in the tire width direction and a second protruding portion protruding in the tire width direction and separated from the first protruding portion in the tire circumferential direction. For example, Patent Document 1 discloses a tire in which a sidewall is provided with a connecting portion extending in the tire circumferential direction so as to connect the first protruding portion and the second protruding portion and projecting in the tire width direction. There is.

As a result, not only the regions of the first protruding portion and the second protruding portion but also the connecting portion can secure the rubber thickness of the region between the first protruding portion and the second protruding portion, so that the sidewall can withstand cutting. Performance can be improved. By the way, the protruding height of the connecting portion according to Patent Document 1 is the same over the entire area, and is the same as the protruding height of the first protruding portion and the second protruding portion. As a result, the mud drainage between the first protruding portion and the second protruding portion is hindered by the connecting portion, so that the mud draining performance is deteriorated.

Japanese Unexamined Patent Publication No. 2017-128267

An object of the present disclosure is to provide a tire capable of achieving both cut resistance and mud drainage performance of a sidewall.

The tire according to the present disclosure includes a tread and a sidewall, and at least one of the sidewalls is a tire having a plurality of side blocks protruding from the sidewall reference plane, and the plurality of side blocks are in the tire circumferential direction. Includes first and second side blocks that are spaced apart from each other. The first side block has a groove extending inward from the side surface facing the adjacent second side block, and the second side block has a lower height from the reference plane toward the adjacent first side block. The slope extends into the groove of the adjacent first side block.

Cross-sectional view of a main part of a tire according to an embodiment on the tire meridional surface A perspective view showing a main part of a tire according to the same embodiment. A perspective view showing a main part of a tire according to the same embodiment. Side view of the main part of the tire according to the same embodiment (tire width direction view) Enlarged sectional view taken along line III-III in FIG. Enlarged sectional view taken along line IV-IV in FIG. FIG. 4 is an enlarged sectional view taken along line VV. Enlarged sectional view of the main part of the side block Enlarged sectional view of the main part of the side block Enlarged sectional view of the main part of the side block Enlarged sectional view of the main part of the side block

Hereinafter, an embodiment of the tire according to the present disclosure will be described with reference to FIGS. 1 to 8.

As shown in FIG. 1, the tire 1 which is an example of the embodiment includes a pair of beads 11, a sidewall 12 extending outward from each bead 11 in the tire radial direction D2, and a tread 13. The tread 13 has a tread surface 13a in contact with the ground, and is connected to the outer end of each of the pair of sidewalls 12 in the tire radial direction D2. As will be described in detail later, the tire 1 has a plurality of side blocks protruding from the reference surface S2 in at least one of the pair of sidewalls 12. The tire 1 is mounted on a rim (not shown).

In FIGS. 1 and 4, the first direction D1 is the tire width direction D1 parallel to the tire rotation axis, and the second direction D2 is the tire radial direction D2 which is the diameter direction of the tire 1. The direction D3 of 3 is the tire circumferential direction D3, which is the direction around the tire rotation axis. The tire equatorial plane S1 is a plane orthogonal to the tire rotation axis and is located at the center of the tire width direction D1, and the tire meridional plane is a plane including the tire rotation axis and is a tire equatorial plane. It is a plane orthogonal to S1.

In the tire width direction D1, the inside is the side close to the tire equatorial plane S1, and the outside is the side far from the tire equatorial plane S1. Further, in the tire radial direction D2, the inner side is the side close to the tire rotation axis, and the outer side is the side far from the tire rotation axis.

The bead 11 includes a bead core 11a formed in an annular shape and a bead filler 11b arranged outside the tire radial direction D2 of the bead core 11a. For example, the bead core 11a is formed by laminating a rubber-coated bead wire (for example, a metal wire), and the bead filler 11b is formed by forming a hard rubber in a tapered shape tapering outward in the tire radial direction D2. ing.

Further, the tire 1 includes a carcass 14 bridged between the pair of bead cores 11a and 11a, and an inner liner 15 arranged inside the carcass 14 and facing the internal space of the tire 1 filled with air. There is. The carcass 14 and the inner liner 15 are arranged along the inner circumference of the tire over the bead 11, the sidewall 12, and the tread 13.

The bead 11 includes a rim strip rubber 11c arranged outside the carcass 14 in the tire width direction D1. The rim strip rubber 11c constitutes the outer surface of the bead 11 in contact with the rim. The sidewall 12 includes a sidewall rubber 12a arranged outside the carcass 14 in the tire width direction D1. The sidewall rubber 12a constitutes the outer surface of the sidewall 12.

The tread 13 includes a tread rubber 13b constituting the tread surface 13a and a belt 13c arranged between the tread rubber 13b and the carcass 14. The belt 13c includes a plurality of (four in FIG. 1) belt plies 13d. For example, the belt ply 13d includes a plurality of belt cords (for example, organic fibers or metals) arranged in parallel with each other and a topping rubber for covering the belt cords.

The carcass 14 is composed of at least one carcass ply 14a (two in FIG. 1). The carcass ply 14a is folded around the bead core 11a so as to involve the bead core 11a. Further, the carcass ply 14a includes a plurality of ply cords (for example, organic fibers and metals) arranged in a direction substantially orthogonal to the tire circumferential direction D3, and a topping rubber for covering the ply cords.

The inner liner 15 is excellent in a function of blocking gas permeation in order to maintain the air pressure of the tire 1. In the present embodiment, in the sidewall 12, the inner liner 15 is in close contact with the inner peripheral side of the carcass 14, and no other member is interposed between the inner liner 15 and the carcass 14. In addition, another member may be provided between the carcass 14 and the inner liner 15.

The thickness of the inner liner 15 on the sidewall 12 is, for example, 90% to 180% or 120% to 160% of the thickness of the inner liner 15 on the tread 13. When another member is provided between the carcass 14 and the inner liner 15, the shortest distance (Dm) from the carcass ply 14a arranged on the innermost peripheral side to the inner peripheral surface of the tire (inner peripheral surface of the inner liner 15). Satisfies the above relationship. That is, the distance (Dm) on the sidewall 12 may be 90% to 180% or 120% to 160% of the distance (Dm) on the tread 13.

As shown in FIGS. 1 to 3, the tread rubber 13b is partitioned by a plurality of main grooves 13e extending in the tire circumferential direction D3, a plurality of sub-grooves 13f extending in the tire width direction D1, and a main groove 13e and a sub-groove 13f. It is provided with a plurality of blocks 13 g to be formed. The plurality of blocks 13g are arranged so as to be lined up in the tire circumferential direction D3. The plurality of blocks 13g preferably include a plurality of shoulder blocks arranged along the ground contact end of the tread 13. Further, it is preferable that the plurality of auxiliary grooves 13f extend beyond the ground contact end of the tread 13 to the outer end of the tread 13 in the tire width direction D1. In this case, good drainage and mud drainage performance of the dread 13 can be obtained. In the present disclosure, the tread pattern is not particularly limited.

In FIGS. 2 and 3, the main rotation direction of the tire 1 is indicated by an arrow X. In the present specification, the "tire main rotation direction" means the rotation direction when the vehicle on which the tire 1 is mounted moves forward. In the present specification, the term "left and right" is used for the tire 1 and its components for convenience of explanation. The "right side" of the tire 1 means the right side when the tire 1 mounted on the vehicle is viewed from the front of the vehicle, and the "left side" means the tire 1 mounted on the vehicle in front of the vehicle. It means the left side when viewed from.

2 and 3 show the sidewall 12 on the right side of the tire 1. The sidewall 12 has a plurality of side blocks as described above. The block pattern of the left sidewall 12 may be the same as the block pattern of the right sidewall 12. The side blocks of the left and right sidewalls 12 are formed in a point-symmetric pattern that overlaps with the original shape when the tire 1 is rotated 180 ° about an axis along the tire radial direction D2 passing through the tire equatorial plane S1. It may be formed in completely different patterns from each other. In the tire according to the present disclosure, the first side block 2 and the second side block 3, which will be described later, are formed on at least one of the left and right sidewalls.

The side wall of each side block is not perpendicular to the upper surface of the block, but is curved so as to spread outward from the upper side to the lower side of the block. At least a part of the side wall is curved so as to be convex toward the inside of the block.

Hereinafter, the configuration of the sidewall 12 will be described in detail with reference to FIGS. 2 to 4. FIG. 4 is a diagram schematically showing the side view shape of each side block, assuming that the side wall of each side block is perpendicular to the upper surface of the block for convenience of explanation. 5 to 7 are views showing a part of the cross sections of line III-III, line IV-IV, and line VV in FIG. 4, respectively. In the following description, FIGS. 5 to 7 will be referred to as appropriate.

As shown in FIGS. 2 to 4, the plurality of side blocks formed on the sidewall 12 include the first side block 2 and the second side block 3 which are alternately arranged at intervals in the tire circumferential direction. It has been. Each side block is a protrusion protruding outward in the tire width direction from the reference surface S2 (see FIGS. 1, 5 to 7) of the sidewall 12, and is a sidewall rubber 12a constituting the outer surface of the sidewall 12. Is formed in. The sidewall rubber 12a is thickened in the portion where the side block is formed, and the durability against an external impact is high. That is, the sidewall 12 on which the side block is formed is strong against an impact from the outside and has excellent cut resistance.

Here, the reference surface S2 means the outer surface of the sidewall 12 when the side block does not exist. In other words, it is a virtual surface under the side block, which is a surface along the outer surface of the sidewall 12 in the portion where the side block is not formed. The reference plane of the sidewall 12 is also called a profile plane. In the cross section of the tire meridional surface, the outer surface of the sidewall 12 may be composed of a plurality of arcs having different radii of curvature.

As described above, the plurality of side blocks improve the cut resistance of the sidewall 12 and protect the sidewall 12 when traveling on a rough road such as a rocky road surface. Considering only the cut resistance, it is sufficient to simply arrange a large side block. However, considering the running performance of a muddy road surface with ruts, it is necessary to provide a side block that enhances the mud drainage performance of the tire and exhibits good side traction. In order to improve the mud drainage performance of the sidewall 12, it is necessary to form an appropriate uneven pattern along the tire circumferential direction. Therefore, in general, there is a trade-off relationship between the cut resistance performance and the mud drainage performance of the sidewall 12.

As a result of diligent studies on such issues, the present inventor has succeeded in achieving good mud drainage performance while ensuring excellent cut resistance by improving the side block. By forming the side block including the first side block 2 and the second side block 3 in the sidewall 12, the cut resistance performance and the mud drainage performance of the sidewall 12 are highly compatible with each other.

The first side block 2 and the second side block 3 are alternately arranged one by one in the tire circumferential direction with a gap 12d. The first side block 2 and the second side block 3 are both protrusions protruding from the reference surface S2, but have different shapes and sizes from each other. The sidewall 12 is provided with the same number of these two types of side blocks. The gap 12d formed between the side blocks is connected to the auxiliary groove 13f of the tread 13. In the side view of the tire 1, the gap 12d and the sub-groove 13f are arranged side by side in the tire radial direction, and the side block and the block 13g are arranged side by side in the tire radial direction.

As shown in FIG. 5, the sub-groove 13f and the block 13g of the tread 13 may be arranged over the sidewall 12. Specifically, the outer end portion of the auxiliary groove 13f in the tire width direction D1 and the outer end portion of the block 13g in the tire width direction D1 may be arranged on the sidewall 12, respectively. That is, the outer end portion of the auxiliary groove 13f in the tire width direction D1 and the outer end portion of the block 13g in the tire width direction D1 may be formed of sidewall rubber 12a, respectively.

The outer end of the first side block 2 in the tire radial direction D2 may be arranged outside the tire radial direction D2 with respect to the groove bottom of the auxiliary groove 13f. The outer end of the first side block 2 in the tire radial direction D2 may be connected to the outer end of the block 13g in the tire width direction D1. The outer end of the second side block 3 in the tire radial direction D2 may also be arranged outside the tire radial direction D2 with respect to the groove bottom of the auxiliary groove 13f. The outer end of the second side block 3 in the tire radial direction D2 may be connected to the outer end of the block 13g in the tire width direction D1.

It is preferable that the first side block 2 and the second side block 3 are arranged at least on the outer portion of the sidewall 12 in the tire radial direction D2. In the present embodiment, each side block is arranged outside the tire radial direction D2 from the bead end position 12c (see FIG. 1) of the sidewall 12. Further, it is preferable that each side block is arranged outside the tire radial direction D2 with respect to the tire maximum width position 12b (see FIG. 1) of the sidewall 12.

Here, the bead end position 12c means a position on the outer surface of the sidewall 12 along the outer end 11d of the bead filler 11b in the tire radial direction D2 and the tire width direction D1. The tire maximum width position 12b means a position on the outer surface of the sidewall 12 that is aligned with the position where the distance W1 is maximum and the tire width direction D1 shown in FIG. The distance W1 is a distance along the tire width direction D1 from the outer surface of the carcass 14 on the left sidewall 12 to the outer surface of the carcass 14 on the right sidewall 12.

By arranging each side block on the outer portion of the sidewall 12 in the tire radial direction D2, when the tire 1 sinks due to the weight of the vehicle in a muddy area or a sandy area, each side block comes into contact with the mud or sand. A large side traction can be realized. Also, in rocky areas, each side block touches the uneven rock. That is, each side block touches the ground on rough roads such as muddy areas, sandy areas, and rocky areas. In addition, each side block does not touch the ground during normal driving on a flat road.

The first side block 2 is larger than the second side block 3 and extends inward in the tire radial direction from the second side block 3. As will be described in detail later, the second side block 3 has a first portion extending in the tire radial direction and a second portion extending from the first portion in the tire circumferential direction and including a slope 35c. In the present embodiment, the first portion is the main portion 34 and the second portion is the inclined portion 35. The second side block 3 is connected to the first side block 2 located on the front side in the tire main rotation direction with respect to the second side block 3 via the inclined portion 35.

On the sidewall 12, two types of side block pairs connected via the inclined portion 35 are arranged at equal intervals along the tire circumferential direction. The regular repeated arrangement of the pair of side blocks achieves both excellent cut resistance and mud drainage performance, and improves steering stability when traveling on rough roads.

In the following, for convenience of explanation, the tire main rotation direction is referred to as “direction D31”, and the direction opposite to the tire main rotation direction is referred to as “direction D32” (see FIG. 4). The tire 1 is preferably used in the direction indicated by the arrow X as the main rotation direction, but it is also possible to use the direction opposite to the arrow X as the main rotation direction.

Both the first side block 2 and the second side block 3 extend inward in the tire radial direction from the tread 13 side. The portion of each side block located inside in the tire radial direction extends in the direction D31 (front side in the tire main rotation direction). The first side block 2 extends to a position aligned with the second side block 3 on the direction D31 side in the tire radial direction. That is, a part of the first side block 2 overlaps with the second side block 3 of another side block pair that is not connected by the inclined portion 35 in the tire radial direction. A part of the first side block 2 is arranged to face the second side block 3 with a gap 12d inside the tire radial direction from the second side block 3.

The first side block 2 has a third portion extending in the tire radial direction and a fourth portion extending from the third portion in the tire circumferential direction. In the present embodiment, the third portion is the main portion 24 including the second region 21 and the first region 22, and the fourth portion is inclined to extend to a position where it overlaps with the second side block 3 on the direction D31 side in the tire radial direction. Part 25. The first region 22 is a portion having a lower height from the reference plane S2 than the second region 21. The first side block 2 further has a groove 23 extending from the side surface of the block facing the second side block 3 adjacent to the direction D32 side to the inside of the block, and has a substantially sickle shape as a whole. As will be described in detail later, the inclined portion 35 of the second side block 3 is formed over the groove 23, and the tip end 35a thereof is located in the groove 23.

Similar to the first side block 2, the second side block 3 has a height from the reference surface S2 toward the adjacent first side block 2 and the main portion 34 including the fourth region 31 and the third region 32. It has an inclined portion 35 including a lowered inclined surface 35c. The third region 32 is a portion having a lower height from the reference plane S2 than the fourth region 31. The inclined portion 35 extends in the tire circumferential direction, is connected to the first side block 2, and is formed over the inside of the groove 23. In the second side block 3, the inclined portion 35 extends from the inner end side in the tire radial direction of the main portion 34 in the tire circumferential direction (direction D31), and exhibits a substantially L-shape as a whole.

In the present embodiment, in the main portions 24 and 34 of each side block, the region where the height from the reference surface S2 is high (high protrusion portion) and the region where the height from the reference surface is low (low protrusion portion) are in the tire circumferential direction. It is placed adjacent to. Further, in each of the main portions 24 and 34, the low protrusion portion is arranged on the direction D31 side, and the high protrusion portion is arranged on the direction D32 side. As a result, the sidewall 12 has the first region 22, the second region 21, the third region 32, and the fourth region 31 of the second side block 3 in this order along the tire circumferential direction. Arranged in, regular irregularities are formed. Further, there is a gap 12d between the side blocks, which is lower in height than the low protrusion. Such an uneven structure realizes a large side traction and highly achieves both cut resistance and mud drainage performance.

In the present embodiment, the second region 21 of the first side block 2 has a higher height from the reference surface S2 than the third region 32 of the second side block 3, and the fourth region 31 of the second side block 3 has a height higher than that of the third region 32. , The height from the reference plane S2 is higher than that of the first region 22 of the first side block 2. The relationship between the height of the second region 21 of the first side block 2 and the height of the fourth region 31 of the second side block 3 is not particularly limited, but in the present embodiment, the height of each high protrusion is from the reference surface S2. The heights are the same as each other. In this case, it is easy to obtain uniform cut resistance along the tire circumferential direction. Further, the height of the first region 22 of the first side block 2 from the reference surface S2 is the same as the height of the third region 32 of the second side block 3. In this case, uniform mud drainage performance can be easily obtained along the tire circumferential direction.

The sidewall 12 may have a side rib 8 protruding from the reference surface S2. The side ribs 8 are arcuate and fine line-shaped protrusions that extend in the tire circumferential direction and are gently curved, cross the gap 12d in the vicinity of the tread 13, and connect adjacent side blocks to each other. The height of the side ribs 8 is not particularly limited, but in the present embodiment, it is the same as the height of the high protrusions (second region 21 and fourth region 31) of each side block. The side ribs 8 further cross the low protrusions (first region 22 and third region 32) of each side block and connect the high protrusions of adjacent side blocks to each other. That is, the side rib 8 has a higher height from the reference surface S2 than the first region 22 and the third region 32, and connects the second region 21 and the fourth region 31. The side rib 8 contributes to the improvement of cut resistance and side traction performance together with the side block, for example.

Hereinafter, each of the first side block 2 and the second side block 3 will be described in more detail.

<1st side block 2>
The first side block 2 has a groove 23 extending in the direction D31 from the side surface facing the adjacent second side block 3. The groove 23 extends inside the main portion 24 of the first side block 2, is formed in a side view concave or U shape, and is terminated inside the first side block 2. The main portion 24 includes a first region 22 and a second region 21 having a height higher than the reference surface S2 than the first region 22. In the present embodiment, the groove 23 opens toward the direction D32, and the groove 23 is surrounded by the second region 21 on three sides other than the opening.

The first side block 2 has an inclined portion 25 extending in the direction D31 opposite to the groove 23 on the extension line of the groove 23. The first side block 2 is formed in a substantially sickle shape as a whole by the groove 23 extending in the tire circumferential direction, the main portion 24 extending in the tire radial direction, and the inclined portion 25. The substantially sickle-shaped first side block 2 has a long edge extending in the tire circumferential direction and the radial direction, and more effectively improves the side traction performance of the tire 1.

[Groove 23]
The groove 23 is a portion surrounded by the second region 21 on both sides in the tire radial direction and on three sides in the direction D31, and the height from the reference surface S2 is lower than the surroundings. The height of the deepest portion of the groove 23 may be the same as the height of the reference surface S2. Since the inclined portion 35 of the second side block 3 including the inclined surface 35c whose height from the reference surface S2 gradually decreases toward the tip end 35a is inserted in at least a part of the groove 23, the height of the bottom surface changes. There is an area to do. As will be described in detail later, the wall of the groove 23 is higher than the slope 35c from the reference surface S2.

The groove 23 is preferably formed longer in the tire circumferential direction than in the tire radial direction. The tire circumferential length of the groove 23 (hereinafter referred to as “length L23”) is not particularly limited, but as an example, it is 30% to 70% of the tire circumferential length of the main portion 24. The tire radial length of the groove 23 (hereinafter referred to as “width W23”) is preferably 50% or less of the length L23, and is, for example, 20% to 50%. The width W23 of the groove 23 may be constant over the entire length of the groove 23, but in the present embodiment, the width W23 gradually narrows from the opening toward the end.

The groove 23 may be formed parallel to the tire circumferential direction, but in the present embodiment, the groove 23 is inclined with respect to the tire circumferential direction so that the end thereof is located inside the tire radial direction with respect to the opening. That is, the groove 23 is terminated inside the first side block 2 and is inclined with respect to the tire circumferential direction so as to be gradually located inward in the tire radial direction as the distance from the base end 35b of the inclined portion 35 increases. Further, in the groove 23, there is a gap 9 surrounded by the second region 21 and the inclined portion 35 of the second side block 3 and having a height lower than the surroundings. An annular edge is formed around the gap 9, and the annular edge provides a traction effect in various directions.

As shown in FIG. 6, the bottom surface 9a of the gap 9 is formed at the same height as the reference surface S2, and constitutes the deepest portion of the groove 23, for example. In the present embodiment, the tip 35a of the inclined portion 35 exists at a position away from the end of the groove 23, and is located closer to the opening than the end of the groove 23. That is, the tire circumferential length of the gap 9 is longer than the tire circumferential length of the portion of the inclined portion 35 existing in the groove 23.

[Main part 24]
The main portion 24 extends inward in the tire radial direction from the main portion 34 of the second side block 3 and is formed larger than the main portion 34. The second region 21 of the main portion 24 is larger than the first region 22, and the portion of the main portion 24 located inside in the tire radial direction is composed of only the second region 21. As described above, the second region 21 and the first region 22 are adjacent to each other in the tire circumferential direction in the vicinity of the tread 13, the second region 21 is arranged on the direction D31 side, and the first region 22 is arranged on the direction D32 side. ing. In the vicinity of the tread 13, the second region 21 and the first region 22 are formed to have the same size, or the first region 22 is formed larger than the second region 21.

In the present embodiment, the second region 21 is also arranged inside the tire radial direction D2 of the first region 22 and is connected to the inner end of the tire radial direction D2 of the first region 22. The second region 21 may be provided with a recess 21a extending in the tire radial direction D2 at the end portion on the tire circumferential direction D3 side. The details of the recess 21a will be described later.

The second region 21 extends inward in the tire radial direction from the tread 13 side beyond the side ribs 8 and bends in the direction D31 side along the tire radial inner end of the first region 22. Further, the second region 21 is bent again in the direction D32 so as to face the portion of the first region 22 along the inner end in the tire radial direction with a groove-shaped gap. This gap is a groove 23, and the second region 21 has a substantially sickle shape as a whole, like the first side block 2. The portion of the second region 21 located inside the tire radial direction from the groove 23 extends to a position overlapping the main portion 34 of the second side block 3 on the direction D32 side in the tire radial direction.

As shown in FIG. 7, the height of the first region 22 may be, for example, about ½ of the height of the second region 21. The height of the first region 22 from the reference surface S2 is not particularly limited, but as an example, it is 30% to 70% of the height of the second region 21 from the reference surface S2. The first region 22 extends from the tread 13 side beyond the side ribs 8 inward in the tire radial direction, and has a substantially rectangular shape in the side view. The tire radial length of the first region 22 is shorter than the tire radial length of the second region 21, and a second region 21 bent toward the direction D31 is formed inside the tire radial direction of the first region 22. ing.

[Inclined portion 25]
The inclined portion 25 extends from the end portion of the main portion 24 on the direction D31 side. The inclined portion 25 has an inclined surface 25c whose height from the reference surface S2 becomes lower toward the tip end 25a. In the present embodiment, the inclined portion 25 is located on the extension of the groove 23, and like the groove 23, the tip 25a side is located inside the tire radial direction with respect to the base end 25b side connected to the main portion 24. It is tilted with respect to the tire circumferential direction. The inclined portion 25 has a substantially rectangular shape in a side view. The tire radial length of the inclined portion 25 is gradually shortened from the base end 25b toward the tip end 25a.

As described above, the inclined portion 25 extends to a position where it overlaps the second side block 3 on the direction D31 side in the tire radial direction, and is arranged so as to face the second side block 3 with a gap 12d. The inclined portion 25 is further arranged so as to face the main portion 24 of the first side block 2 on the direction D31 side with a gap 12d. The gap 12d is formed in a substantially L shape between the inclined portion 25 and the side block pair on the direction D31 side. Further, the side wall located at the inner end in the tire radial direction of the first side block 2 is inclined so as to be convex toward the outer side in the tire radial direction, and is bent at the boundary portion between the main portion 24 and the inclined portion 25. There is.

The slope 25c of the inclined portion 25 is inclined so that the height from the reference surface S2 gradually decreases from the base end 25b side toward the tip end 25a side. That is, the slope 25c is inclined so as to approach the reference surface S2 toward the tip 25a side. The inclined portion 25 including the slope 25c contributes to both the cut resistance performance and the mud draining performance of the sidewall 12 as in the inclined portion 35 including the slope 35c. The inclination angle of the slope 25c of the inclined portion 25 with respect to the reference surface S2 is, for example, gentler than the inclination angle of the slope 35c of the inclined portion 35 with respect to the reference surface S2 (see FIG. 6).

<Second side block 3>
The second side block 3 has a rectangular main portion 34 extending in the tire radial direction and an inclined portion 35 extending in the tire circumferential direction from the inner end side of the main portion 34 in the tire radial direction, and is substantially L as a whole. It has a character shape. The side wall of the main portion 34 and the side wall of the inclined portion 35 located at the inner end in the tire radial direction of the second side block 3 are formed on the same straight line. The inclined portion 35 extends in the tire circumferential direction, is connected to the first side block 2, and is formed over the inside of the groove 23. The inclined portion 35 is an extending portion extending from the end portion of the main portion 34 on the direction D31 side, and is connected to the first side block 2 in the groove 23.

The inclined portion 35, which is a portion including the inclined surface 35c, is connected to the first side block 2 in the groove 23 of the first side block 2. In the present embodiment, the slope 35c is formed over the entire length of the inclined portion 35, and the start end of the slope 35c coincides with the base end 35b of the inclined portion 35. The starting end of the slope 35c is a portion where the height of the slope 35c begins to decrease, and the height from the reference surface S1 is the highest. The base end 35b of the inclined portion 35 is the base of the inclined portion 35 connected to the main portion 34. Further, the end of the slope 35c, which is the end opposite to the start end, coincides with the tip 35a of the inclined portion 35, which is the end opposite to the base end 35b.

[Main part 34]
The main portion 34 is smaller than the main portion 24 of the first side block 2, and is surrounded by two first side blocks 2 on the inner side in the tire radial direction and on both sides in the tire circumferential direction via a gap 12d. The fourth region 31 of the main portion 34 is formed in a rectangular shape in a side view in which the length in the tire circumferential direction is gradually shortened from the tread 13 side toward the inside in the tire radial direction. On the other hand, the third region 32 has a tire circumferential length gradually increasing from the tread 13 side toward the inner side in the tire radial direction, and is formed in a substantially triangular shape in the side view.

The main portion 34 includes a third region 32 and a fourth region 31 having a height higher than the reference surface S2 than the third region 32. As described above, the fourth region 31 and the third region 32 are adjacent to each other in the tire circumferential direction, and the fourth region 31 is arranged on the direction D31 side and the third region 32 is arranged on the direction D32 side. In the present embodiment, the inclined portion 35 extends from the end portion of the third region 32 on the direction D31 side. That is, the third region 32 is interposed between the fourth region 31 and the inclined portion 35. The main portion 34 has a third region 32 whose height from the reference surface S2 is the same as or lower than the start end of the slope 35c (base end 35b of the inclined portion 35), and the third region 32 is on the slope 35c. Adjacent. The fourth region 31 of the main portion 34 exists at a position away from the slope 35c. In this case, good mud drainage performance can be easily ensured even between the two side blocks connected by the inclined portion 35.

As shown in FIG. 7, the height of the third region 32 may be, for example, about ½ of the height of the fourth region 31. The height of the third region 32 from the reference surface S2 is not particularly limited, but as an example, it is 30% to 70% of the height of the fourth region 31 from the reference surface S2. In the present embodiment, as described above, the height of the fourth region 31 and the height of the second region 21 of the first side block 2 are the same, and the protruding portions are connected in the tire circumferential direction via the side ribs 8. ing. Further, the height of the third region 32 and the height of the first region 22 of the first side block 2 are the same.

[Inclined portion 35]
As described above, the inclined portion 35 has a slope 35c whose height from the reference surface S2 gradually decreases from the base end 35b side connected to the third region 32 of the main portion 34 toward the tip end 35a side located in the groove 23. have. As a result, good mud drainage performance can be ensured between the two side blocks provided with the inclined portion 35 to improve the cut resistance. The height of the inclined portion 35 (slope 35c) from the reference surface S2 is, for example, the highest at the base end 35b and the lowest at the tip 35a.

The slope 35c may be a curved surface or a stepped uneven surface, but in the present embodiment, it is a flat slope without unevenness. The inclined portion 35 is formed with a slope 35c inclined at a constant angle over the entire length thereof. Further, the slope 35c is inclined with respect to the reference surface S2 at an angle larger than the inclination angle of the slope 25c of the inclined portion 25 of the first side block 2. The inclination angle of the slope 35c with respect to the reference surface S2 is not particularly limited, but is, for example, 10 ° to 40 ° as an example.

The height of the tip 35a of the inclined portion 35 is lower than the height of the second region 21 surrounding the groove 23 of the first side block 2. In other words, the wall of the groove 23 is higher than the end of the slope 35c located in the groove 23 from the reference surface S2. In this case, the tip 35a of the inclined portion 35 is completely accommodated in the groove 23, and even if the inclined portion 35 has a slope 35c in which the height of the inclined portion 35 gradually decreases toward the tip 35a, the excellent cut resistance performance is obtained. Can be secured. The height of the end of the slope 35c (the tip 35a of the inclined portion 35) may be zero.

In the present embodiment, the height of the starting end (base end 35b of the inclined portion 35) of the slope 35c is the same as the height of the third region 32. Further, the wall of the groove 23 is higher in height from the reference plane than the base end 35b of the inclined portion 35. In this case, the entire portion of the inclined portion 35 located in the groove 23 is completely accommodated in the groove 23, and excellent cut resistance can be ensured.

As described above, the inclined portion 35 is connected to the first side block 2 in the groove 23 of the first side block 2. Further, both sides of the slope 35c in the tire radial direction are connected to the wall of the groove 23. That is, a part of the first side block 2 and the second side block 3 is continuous in the tire radial direction. In this case, the rigidity of the side block becomes high, and the effect of improving the cut resistance becomes more remarkable.

The inclined portion 35 may be formed parallel to the tire circumferential direction, but in the present embodiment, the inclined portion 35 extends inward in the tire radial direction toward the direction D31 side. That is, the inclined portion 35 is gradually positioned inward in the tire radial direction so that the tip 35a on the direction D31 side is located on the inner side in the tire radial direction with respect to the base end 35b on the direction D32 side, in other words, as the distance from the start end of the slope 35c increases. So that it is tilted with respect to the tire circumferential direction.

The inclined portion 35 is formed, for example, longer in the tire circumferential direction than in the tire radial direction. In the present embodiment, the tire radial length (width) of the inclined portion 35 becomes narrower toward the first peripheral direction side D31. Further, the width of the inclined portion 35 is wider than the width of the side rib 8.

The configuration of the tire 1 according to the present embodiment is as described above, and next, the operation of the tire 1 according to the present embodiment will be described.

First, since the inclined portion 35 including the inclined surface 35c of the second side block 3 extends into the groove 23 of the first side block 2, the inclined portion 35 secures the rubber thickness of the region between the two side blocks. Can be done. As a result, the cut resistance of the sidewall 12 can be improved. In particular, it is preferable that both sides of the slope 35c in the tire radial direction are connected to the first side block 2 in the groove 23.

By the way, the mud drainage between the two side blocks may be hindered by the inclined portion 35. On the other hand, in the present embodiment, the inclined portion 35 has an inclined portion 35c whose height from the reference surface S2 gradually decreases toward the tip end 35a side of the inclined portion 35. As a result, mud can be smoothly discharged even in the portion where the inclined portion 35 is formed.

Moreover, the third region 32 of the main portion 34 having a low height from the reference surface S2 is arranged adjacent to the inclined portion 35. That is, the third region 32 is located between the second region 21 of the main portion 24 of the first side block 2 having a high height from the reference surface S2 and the fourth region 31 of the main portion 34 of the second side block 3. Is placed. As a result, mud can be drained between the second region 21 and the fourth region 31 via not only the inclined portion 35 but also the third region 32, and the mud drainage performance due to the block shape connected in the tire circumferential direction. The decrease in tires can be effectively suppressed.

Further, the height of the region on the base end 35b side connected to the third region 32 of the inclined portion 35 is higher than the height of the region on the tip 35a side of the inclined portion 35. As a result, the rubber thickness of the region on the third region 32 side of the inclined portion 35 can be sufficiently secured, and the cut resistance of the region on the third region 32 side of the inclined portion 35 can be improved.

The height of the region on the tip 35a side of the inclined portion 35 is lower than the region on the base end 35b side, but the region on the tip 35a side of the inclined portion 35 is in the groove 23 of the first side block 2. It is sandwiched by the second region 21 from both sides in the tire radial direction D2. As a result, by forming the slope 35c, excellent cut resistance can be ensured even if the height of the inclined portion 35 is gradually reduced toward the tip end 35a side of the inclined portion 35.

By the way, the first side block 2 and the second side block 3 include surface and edge components. Then, the uneven shape is formed in the portion in contact with the mud, sand, and rock, so that the area in contact with the mud, sand, and rock becomes large. In addition, the surface and edges due to the uneven shape make it easier to touch mud, sand, and rock at various positions. In this way, the traction performance is improved by forming the uneven shape in the portion in contact with the mud, sand, and rock.

Further, since the sidewall 12 includes the gap 9, it is possible to generate a traction effect due to the edges formed around the gap 9. As a result, for example, the mud drainage performance is further improved, and a large traction performance can be exhibited. Further, since the entire circumference of the gap 9 is surrounded by the second region 21 and the inclined portion 35 (slope 35c), the edge of the gap 9 also extends in an annular shape. Thereby, for example, the traction effect can be generated in various directions of the tire radial direction D2 and the tire circumferential direction D3.

As described above, the tire 1 according to the present embodiment includes a sidewall 12 on which a plurality of side blocks are formed. The plurality of side blocks include a first side block 2 and a second side block 3 which are alternately arranged at intervals in the tire circumferential direction. The first side block 2 has a groove 23 extending in the tire circumferential direction from the side surface facing the second side block 3, and the second side block 3 extends in the tire circumferential direction and has a groove 23 of the first side block 2. It has an inclined portion 35 formed inward. The inclined portion 35 includes an inclined surface 35c inclined so that the height from the reference surface S2 becomes lower toward the adjacent first side block 2.

According to such a configuration, the inclined portion 35 of the second side block 3 can secure the rubber thickness of the region between the first side block 2 and the second side block 3. Moreover, since the inclined portion 35 has a slope 35c whose height becomes lower toward the first side block 2, mud drainage between the first side block 2 and the second side block 3 is removed via the inclined portion 35. It can be carried out. As a result, it is possible to achieve both the cut resistance performance of the sidewall 12 and the mud drainage performance.

Further, in the tire 1 according to the present embodiment, the inclined portion 35 of the second side block 3 is connected to the first side block 2 in the groove 23.

According to such a configuration, it is possible to suppress the shortening of the edge length of the end portion of the first side block 2 on the rear side in the tire main rotation direction. As a result, it is possible to secure an edge length extending in the tire radial direction D2 of the first side block 2.

Further, in the tire 1 according to the present embodiment, the first side block 2 is formed to be larger inward in the tire radial direction than the groove 23 to which the inclined portion 35 is connected. Further, the first side block 2 has an inclined portion 25 including a slope 25c extending to the side opposite to the groove 23 and gradually decreasing in height from the reference surface S2 toward the tip end side.

According to such a configuration, the effect of improving the cut resistance becomes more remarkable due to the large first side block 2. Moreover, the tip portion of the inclined portion 35 whose height is lowered in order to improve the mud drainage performance exists in the groove 23 surrounded on three sides by the second region 21 of the first side block 2. As a result, excellent cut resistance can be ensured even if the height is gradually reduced toward the tip of the inclined portion 35. Further, since the inclined portion 25 has an inclined surface 25c inclined so that the height gradually decreases toward the tip side, the cut resistance is improved while ensuring good mud drainage performance.

Further, in the tire 1 according to the present embodiment, the groove 23 of the first side block 2 is surrounded by the second region 21 of the main portion 24 and the inclined portion 35 of the second side block 3, and is more than the surrounding area. A gap 9 having a reduced height is formed.

According to such a configuration, the edge formed around the gap 9 can be made circular, and the effect of improving the side traction performance becomes more remarkable.

Further, in the tire 1 according to the present embodiment, the third region 32 of the second side block 3 is interposed between the fourth region 31 and the inclined portion 35.

According to such a configuration, mud can be drained between the first side block 2 and the fourth region 31 of the second side block 3 via the third region 32.

The tire 1 is not limited to the configuration of the above-described embodiment, and is not limited to the above-mentioned action and effect. Further, the tire 1 may be modified in various ways without departing from the gist of the present disclosure. For example, one or a plurality of configurations according to the following various modification examples may be arbitrarily selected and adopted for the configuration according to the above-described embodiment.

(1) In the tire 1 according to the above embodiment, the inclined portion 35 of the second side block 3 is connected to the first side block 2 in the groove 23 of the first side block 2. However, the tire 1 is not limited to such a configuration. For example, the inclined portion 35 may not be connected to the first side block 2 in the groove 23, but may be connected to the first side block 2 outside the groove 23. That is, if the inclined portion 35 is connected to the first side block 2 outside the groove 23, there may be a gap between the side wall of the groove 23 and the inclined portion 35. Alternatively, the inclined portion 35 may be configured not to be connected to the first side block 2.

(2) In the tire 1 according to the above embodiment, the first side block 2 includes an inclined portion 25 having an inclined surface 25c. However, the tire 1 is not limited to such a configuration. For example, the first side block 2 may not include the inclined portion 25 having the inclined surface 25c.

(3) In the tire 1 engaged in the above embodiment, the inclined portion 35 of the second side block 3 is not formed up to the end of the groove 23 of the first side block 2. The groove 23 has a gap 9 having a bottom surface 9a having the same height as the reference surface S2. However, the tire 1 is not limited to such a configuration. For example, the inclined portion 35 may be formed up to the end of the groove 23.

(4) In the tire 1 according to the above embodiment, the first side block 2 includes a second region 21 and a first region 22 having different heights from the reference surface S2. However, the tire 1 is not limited to such a configuration. For example, the first side block 2 may have the same height over the entire area.

(5) In the tire 1 according to the above embodiment, the second side block 3 includes a fourth region 31 and a third region 32 having different heights from the reference surface S2. However, the tire 1 is not limited to such a configuration. For example, the second side block 3 may have the same height over the entire area.

(6) In the tire 1 according to the above embodiment, the first region 22, the second region 21, the third region 32, and the fourth region 31 are arranged in this order along the tire circumferential direction D3. That is, the high protrusions and the low protrusions are alternately arranged along the tire circumferential direction D3. However, the tire 1 is not limited to such a configuration.

For example, the first region 22 may be arranged between the second region 21 and the third region 32 in the tire circumferential direction D3. Further, the third region 32 may be arranged between the fourth region 31 and the first region 22 in the tire circumferential direction D3.

(7) In the tire 1 according to the above embodiment, the height of the second region 21 from the reference surface S2 is higher than the height of the third region 32 from the reference surface S2. However, the tire 1 is not limited to such a configuration. For example, the height of the second region 21 may be lower than the height of the third region 32. Further, the height of the second region 21 may be the same as the height of the third region 32.

(8) In the tire 1 according to the above embodiment, the height of the fourth region 31 from the reference surface S2 is higher than the height of the first region 22 from the reference surface S2. However, the tire 1 is not limited to such a configuration. For example, the height of the fourth region 31 may be lower than the height of the first region 22. Further, the height of the fourth region 31 may be the same as the height of the first region 22.

(9) In the tire 1 according to the above embodiment, there are two types of side blocks, a first side block 2 and a second side block 3, and the first side block 2 and the second side block 3 are in the tire circumferential direction. It is arranged alternately one by one in D3. However, the tire 1 is not limited to such a configuration.

For example, the first side block 2 (or the second side block 3) may have a region continuously arranged in the tire peripheral direction D3 in a part of the tire peripheral direction D3. Further, the sidewall 12 further includes a third side block different from the first side block 2 and the second side block 3, and the first side block 2, the second side block 3, and the third side block include. They may be arranged in this order along the tire circumferential direction D3.

(10) Further, in the tire 1 according to the above embodiment, the recesses 21a and 31a formed along the edge of the high protrusion of each side block are as shown in FIG. 8A (in FIGS. 8A and 8B). , Only the recess 21a of the first side block 2 is shown), and the curved surface 21b that is convex toward the inside of the first side block 2 is provided. The recesses 21a and 31a may be provided with planes 21c and 21d on both sides of the curved surface 21b, as shown in FIG. 8A, for example.

However, the tire 1 is not limited to such a configuration. For example, the recesses 21a and 31a may be provided with two intersecting planes 21e and 21f so as to be convex toward the inside of the protrusion 2 as shown in FIG. 8B. As shown in FIG. 8B, the intersection angle of the two planes 21e and 21f may be an obtuse angle or a right angle.

Further, in each side block, instead of the recesses 21a and 31a, as shown in FIGS. 8C and 8D (in FIGS. 8C and 8D, only the first side block 2 is shown), the end of the high protrusion portion is shown. A slope of 21 g may be provided along the edge. The slope 21g is, for example, a flat slope without unevenness, as shown in FIG. 8C. Further, as shown in FIG. 8D, the slope 21g may be gently curved so as to be convex toward the outside of the side block.

1 ... Tire, 2 ... 1st side block, 3 ... 2nd side block, 8 ... Side rib, 9 ... Gap, 9a ... Bottom, 11 ... Bead, 11a ... Bead core, 11b ... Bead filler, 11c ... Rim strip rubber, 11d ... outer end, 12 ... sidewall, 12a ... sidewall rubber, 12b ... tire maximum width position, 12c ... bead end position, 12d ... gap, 13 ... tread, 13a ... tread surface, 13b ... tread rubber, 13c ... belt, 13d ... belt ply, 13e ... main groove, 13f ... sub-groove, 13g ... block, 14 ... carcass, 14a ... carcass ply, 15 ... inner liner, 21 ... second region, 21a ... concave, 21b ... curved surface, 21c-21f ... plane, 21 g ... chamfered portion, 22 ... first region, 23 ... groove, 24 ... main portion, 25 ... inclined portion, 25a ... tip, 25b ... base end, 25c ... slope, 31 ... fourth region, 31a ... concave portion. , 32 ... 3rd region, 34 ... main part, 35 ... inclined part, 35a ... tip, 35b ... base end, 35c ... slope, D1 ... tire width direction, D2 ... tire radial direction, D3 ... tire circumferential direction, S1 ... Tire equatorial plane, S2 ... Reference plane

Claims (15)

A tire comprising a tread and a pair of sidewalls, wherein at least one of the pair of sidewalls has a plurality of side blocks protruding from a sidewall reference plane.
The plurality of side blocks include a first side block and a second side block alternately arranged at intervals in the tire circumferential direction.
The first side block has a groove extending into the block from a side surface facing the adjacent second side block.
The second side block has a slope whose height from the reference plane becomes lower toward the adjacent first side block, and the slope extends into the groove of the adjacent first side block. There are tires. The tire according to claim 1, wherein the portion of the second side block including the slope is connected to the first side block in the groove of the first side block. The groove is terminated inside the first side block and is inclined with respect to the tire circumferential direction so as to be gradually located inward in the tire radial direction as the distance from the start end of the slope of the second side block is increased. Item 2. The tire according to Item 1 or 2. The portion of the second side block including the slope is longer in the tire circumferential direction than in the tire radial direction, and is gradually located inward in the tire radial direction as the distance from the start end of the slope of the second side block increases. The tire according to any one of claims 1 to 3, which is inclined with respect to the tire. The tire according to any one of claims 1 to 4, wherein the groove wall of the groove has a height higher than the end of the slope of the second side block located in the groove. The tire according to claim 5, wherein the groove wall has a height higher than the starting end of the slope from the reference plane. The groove terminates inside the first side block and
The tire according to claim 5 or 6, wherein the end of the slope is located at a position away from the end of the groove. The tire according to any one of claims 5 to 7, wherein both sides of the slope in the tire radial direction are connected to the groove wall. The second side block has a first portion extending in the tire radial direction and a second portion extending from the first portion in the tire circumferential direction and including the slope.
The first portion has a region where the height from the reference plane is the same as or lower than the start end of the slope, and the region is adjacent to the slope, any of claims 1 to 8. The tire described in item 1. The tire according to claim 9, wherein the first portion has a region where the height from the reference plane is higher than the start end of the slope, and the region exists at a position away from the slope. The first side block has a third portion extending in the tire radial direction and a fourth portion extending from the third portion in the tire circumferential direction.
The tire according to any one of claims 1 to 10, wherein the fourth portion is inclined so as to have a lower height from the reference plane toward the end thereof. 11. The aspect of claim 11, wherein the slope of the second side block is inclined with respect to the reference surface at an angle larger than the inclination angle of the fourth portion of the first side block with respect to the reference surface. tire. The first side block has a first region and a second region having a height higher than the reference plane than the first region.
The second side block has a third region and a fourth region having a height higher than the reference plane than the third region.
The tire according to claim 1 to 12, wherein the first region, the second region, the third region, and the fourth region are arranged in this order along the tire circumferential direction. The second region of the first side block has a higher height from the reference plane than the third region of the second side block.
13. The tire according to claim 13, wherein the fourth region of the second side block has a higher height from the reference plane than the first region of the first side block. At least one of the sidewalls including the plurality of side blocks has side ribs protruding from the reference plane along the tire circumferential direction.
The side ribs are higher in height from the reference plane than the first region of the first side block and the third region of the second side block, and the second region and the second region of the first side block. The tire according to claim 13 or 14, which is connected to the fourth region of the two side blocks.

Images