JP6969279B2 - tire - Google Patents

Description

The present invention relates to a tire having an uneven structure on the tire side portion.

Conventionally, various tires have been proposed which can suppress deterioration of rubber due to heat generation of the tire and improve the durability of the tire by improving the heat dissipation of the tire side portion. For example, Patent Document 1 below proposes a tire in which the surface area of the tire side portion is increased and the heat dissipation is improved by providing dimples arranged at equal pitches in the tire circumferential direction. In the tire of Patent Document 1, since turbulence is generated in the tire side portion due to the dimple, the heat dissipation efficiency is high and the durability of the tire can be improved.

Japanese Unexamined Patent Publication No. 2013-095211

However, in the tire of Patent Document 1, the rigidity of the portion provided with the dimple is lowered, so that the strain during running becomes large and the rubber may be cracked. Therefore, in the tire of Patent Document 1, deterioration of the rubber due to heat generation of the tire can be suppressed by improving the heat dissipation of the tire side portion, but as a result, the durability of the tire is not significantly improved due to the crack of the rubber. There was a problem.

The present invention has been devised in view of the above circumstances, and an object of the present invention is to provide a tire having improved durability by achieving both rigidity and heat dissipation of the tire.

The present invention is a tire having a concavo-convex structure on the tire side portion, and the concavo-convex structure includes a first concavo-convex portion in which first concave portions and first convex portions are alternately arranged in the tire circumferential direction, and the first concavo-convex portion. On the outside of the tire radial direction of the 1 uneven portion, the second concave-convex portion and the second convex portion are arranged alternately in the tire circumferential direction, and the first uneven portion is arranged over the second uneven portion. It is characterized by including a plurality of protrusions.

In the tire of the present invention, it is desirable that the plurality of protrusions are arranged from the first recess to the second recess, respectively.

In the tire of the present invention, it is desirable that the first convex portion and the second convex portion are arranged at positions where they do not overlap each other in the tire circumferential direction.

In the tire of the present invention, it is desirable that the plurality of protrusions are arranged between the first convex portion and the second convex portion in the tire circumferential direction, respectively.

In the tire of the present invention, the uneven structure includes an intermediate convex portion extending in the tire circumferential direction between the first uneven portion and the second uneven portion, and the plurality of protrusions are respectively on the intermediate convex portion. It is desirable that they are arranged apart from each other.

In the tire of the present invention, it is desirable that the plurality of protrusions extend to the bottom surfaces of the first recess and the second recess, respectively.

In the tire of the present invention, the height of the first concave portion of each protrusion from the bottom surface is 1.1 to 3.0 times the height of the first concave portion of the intermediate convex portion from the bottom surface. Is desirable.

In the tire of the present invention, it is desirable that each of the protrusions extends in the radial direction of the tire.

In the tire of the present invention, it is desirable that the length of each protrusion in the tire circumferential direction is smaller than the length of the first convex portion in the tire circumferential direction.

In the tire of the present invention, it is desirable that the first recess and the second recess are recesses recessed inward in the tire axial direction from the surface of the tire side portion, respectively.

In the tire of the present invention, the uneven structure includes a third uneven portion in which the third concave portion and the third convex portion are alternately arranged in the tire circumferential direction on the outer side of the second uneven portion in the tire radial direction. It is desirable that the plurality of protrusions include a first protrusion arranged from the first uneven portion to the second uneven portion, and a second protrusion arranged from the second uneven portion to the third uneven portion.

In the tire of the present invention, the uneven structure includes a first uneven portion in which the first concave portion and the first convex portion are alternately arranged in the tire circumferential direction, and a second concave portion on the outer side of the first uneven portion in the tire radial direction. And the second convex portion are arranged alternately in the tire circumferential direction, and includes a plurality of protrusions arranged from the first uneven portion to the second uneven portion.

In such a tire, the surface area of the tire side portion can be increased by the first uneven portion, the second uneven portion, and the plurality of protrusions, and the heat dissipation of the tire side portion can be improved. In addition, the protrusions can promote the generation of turbulent flow, and can further improve the heat dissipation of the tire side portion.

Further, since the protrusion can increase the rigidity of the tire side portion, the distortion of the tire side portion can be reduced. Therefore, the tire of the present invention can suppress the deterioration of the rubber due to the heat generation of the tire side portion and the cracking of the rubber due to the distortion of the tire side portion, and can improve the durability of the tire.

It is a tire meridian sectional view which shows one Embodiment of the tire of this invention. It is a partially enlarged view of FIG. It is a side view of a tire. It is a perspective view of the concavo-convex structure. It is sectional drawing of the line AA of FIG. It is a side view of the tire of another embodiment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 shows a cross-sectional view of a tire meridian including a rotation axis of the tire 1 of the present embodiment in a normal state. As shown in FIG. 1, the tire 1 can be suitably adopted for, for example, a pneumatic tire, particularly a run-flat tire capable of traveling a certain distance even in a punctured state.

Here, the "normal state" is a state in which the tire 1 is rim-assembled on a normal rim (not shown) and is adjusted to a normal internal pressure without load. Hereinafter, unless otherwise specified, the dimensions and the like of each part of the tire 1 are values measured in this normal state.

A "regular rim" is a rim defined for each tire in the standard system including the standard on which the tire 1 is based. For example, "standard rim" for JATTA and "Design Rim" for TRA. , ETRTO is "Measuring Rim".

"Regular internal pressure" is the air pressure defined for each tire in the standard system including the standard on which Tire 1 is based. For JATMA, "maximum air pressure", for TRA, the table "TIRE LOAD LIMITS". The maximum value described in "AT VARIOUS COLD INFLATION PRESSURES", or "INFLATION PRESSURE" for ETRTO.

The tire 1 of the present embodiment is arranged into a tread-shaped carcass 6 extending from the tread portion 2 through the sidewall portion 3 to the bead core 5 of the bead portion 4, and outside the tire radial direction a of the carcass 6 and inside the tread portion 2. The belt layer 7 and the tire tread layer 7 are included.

The carcass 6 has at least one carcass ply 6A, and in this embodiment, one carcass ply 6A. In the carcass ply 6A, carcass codes (not shown) are arranged at an angle of, for example, 75 to 90 degrees with respect to the tire circumferential direction b (shown in FIG. 3). As the carcass cord, for example, steel, aromatic polyamide, rayon and the like can be preferably adopted.

The carcass ply 6A includes, for example, a main body portion 6a and a folded portion 6b. The main body portion 6a of the present embodiment reaches the bead core 5 of the bead portion 4 from the tread portion 2 through the sidewall portion 3. The folded-back portion 6b of the present embodiment is connected to the main body portion 6a and is folded back around the bead core 5 from the inside to the outside in the tire axial direction c. Between the main body portion 6a and the folded-back portion 6b of the carcass ply 6A, for example, a bead apex rubber 8 having a triangular cross section extending from the bead core 5 to the outside in the tire radial direction a is arranged.

The belt layer 7 includes at least one belt ply 7A to 7C in the present embodiment. In each of the belt plies 7A to 7C, the belt cords (not shown) are arranged at an angle of preferably 10 to 40 degrees with respect to the tire circumferential direction b. As the belt cord, for example, steel, aromatic polyamide, rayon and the like can be preferably adopted. Such a belt layer 7 can improve the durability of the tire 1 by tightening the carcass 6 with a tag to increase the rigidity of the tread portion 2.

FIG. 2 is a partially enlarged view of FIG. 1, and FIG. 3 is a side view of the tire 1. As shown in FIGS. 2 and 3, the tire 1 of the present embodiment has a concave-convex structure 10 on the tire side portion 9. Here, the tire side portion 9 means a side surface portion of the tire 1 from the tread portion 2 to the bead portion 4 via the sidewall portion 3. The uneven structure 10 of the present embodiment is arranged on the sidewall portion 3.

The concavo-convex structure 10 of the present embodiment includes a first concavo-convex portion 11, a second concavo-convex portion 12, and a plurality of protrusions 13. It is desirable that the first uneven portion 11 is located inside the tire radial direction a, and the first concave portion 11A and the first convex portion 11B are alternately arranged in the tire circumferential direction b. It is desirable that the second uneven portion 12 is outside the tire radial direction a of the first uneven portion 11, and the second concave portion 12A and the second convex portion 12B are alternately arranged in the tire circumferential direction b.

In such a tire 1, the surface area of the tire side portion 9 can be increased by the first uneven portion 11, the second uneven portion 12, and the plurality of protrusions 13, and the heat dissipation of the tire side portion 9 can be improved. Can be done.

FIG. 4 is a perspective view of the concave-convex structure 10. As shown in FIGS. 2 to 4, the plurality of protrusions 13 of the present embodiment are arranged from the first uneven portion 11 to the second uneven portion 12, respectively. It is desirable that the protrusions 13 are arranged at the same position in the tire radial direction a and separated from each other in the tire circumferential direction b.

Such protrusions 13 can promote the generation of turbulent flow, and can further improve the heat dissipation of the tire side portion 9. Further, since the protrusion 13 can increase the rigidity of the tire side portion 9, the distortion of the tire side portion 9 can be reduced. Therefore, the tire 1 of the present embodiment can suppress the deterioration of the rubber due to the heat generation of the tire side portion 9 and the cracking of the rubber due to the distortion of the tire side portion 9, and improve the durability of the tire 1. Can be made to.

As shown in FIGS. 2 and 4, the first recess 11A and the second recess 12A of the present embodiment are each formed as a recess 14 recessed inward from the surface 9a of the tire side portion 9 in the tire axial direction c. There is. In the present embodiment, the first convex portion 11B and the second convex portion 12B are each formed as substantially the same surface as the surface 9a of the tire side portion 9. Such a tire side portion 9 can form the first uneven portion 11 and the second uneven portion 12 while reducing the weight of the tire 1.

In the first uneven portion 11 and the second uneven portion 12, the first convex portion 11B and the second convex portion 12B each project from the surface 9a of the tire side portion 9 to the outside in the tire axial direction c (not shown). It may be omitted). In this case, the first recess 11A and the second recess 12A may be formed as substantially the same surface as the surface 9a of the tire side portion 9, respectively. Such a tire side portion 9 can form the first uneven portion 11 and the second uneven portion 12 while improving the rigidity of the tire 1.

Further, the first uneven portion 11 and the second uneven portion 12 form the first concave portion 11A and the second concave portion 12A as a concave portion 14 recessed inward in the tire axial direction c from the surface 9a of the tire side portion 9, respectively. The first convex portion 11B and the second convex portion 12B may be formed as protrusions protruding outward from the surface 9a of the tire side portion 9 in the tire axial direction c, respectively. Such a tire side portion 9 can form the first uneven portion 11 and the second uneven portion 12 while achieving both weight reduction and rigidity of the tire 1 in a well-balanced manner.

As shown in FIG. 3, the length L1 of the first concave portion 11A in the tire circumferential direction b of the present embodiment is larger than the length L2 of the first convex portion 11B in the tire circumferential direction b. Further, the length L3 of the second concave portion 12A in the tire peripheral direction b of the present embodiment is larger than the length L4 of the second convex portion 12B in the tire peripheral direction b. Such the first uneven portion 11 and the second uneven portion 12 can efficiently generate turbulent flow and further improve the heat dissipation of the tire side portion 9.

As shown in FIGS. 3 and 4, it is desirable that the first convex portion 11B and the second convex portion 12B are arranged at positions that do not overlap each other in the tire circumferential direction b. The first convex portion 11B and the second convex portion 12B of the present embodiment are arranged at positions shifted by a half pitch in the tire circumferential direction b. Such an uneven structure 10 can generate turbulent flow in a dispersed manner in the tire circumferential direction b, and can efficiently cool the entire tire side portion 9.

As shown in FIGS. 2 to 4, it is desirable that the uneven structure 10 further includes an intermediate convex portion 15 extending in the tire circumferential direction b between the first uneven portion 11 and the second uneven portion 12. The intermediate convex portion 15 of the present embodiment continuously extends in the tire circumferential direction b. Such an intermediate convex portion 15 can improve the rigidity of the tire side portion 9.

The plurality of protrusions 13 of the present embodiment are arranged from the first recess 11A to the second recess 12A, respectively. It is desirable that the plurality of protrusions 13 are arranged between the first convex portion 11B and the second convex portion 12B in the tire circumferential direction b, respectively. The plurality of protrusions 13 of the present embodiment are arranged at intermediate positions between the first convex portion 11B and the second convex portion 12B in the tire circumferential direction b, respectively. Such an uneven structure 10 can generate turbulent flow more dispersedly in the tire circumferential direction b, and can more efficiently cool the entire tire side portion 9.

As shown in FIG. 3, it is desirable that the length L5 of each protrusion 13 in the tire circumferential direction b is smaller than the length L2 of the first convex portion 11B in the tire circumferential direction b. Further, it is desirable that the length L5 of each protrusion 13 in the tire circumferential direction b is smaller than the length L4 of the second convex portion 12B in the tire circumferential direction b. Such protrusions 13 have a small amount of rubber for forming the protrusions 13, and can suppress an increase in the weight of the tire 1.

Each protrusion 13 extends, for example, in the tire radial direction a. The plurality of protrusions 13 of the present embodiment are arranged on the intermediate convex portion 15 at equal intervals. Such protrusions 13 can efficiently generate turbulence.

FIG. 5 is a cross-sectional view taken along the line AA of FIG. As shown in FIGS. 4 and 5, it is desirable that the plurality of protrusions 13 extend to the bottom surfaces 11a and 12a of the first recess 11A and the second recess 12A, respectively. Since such a protrusion 13 also generates turbulent flow inside the first recess 11A and the second recess 12A, the tire side portion 9 can be cooled more efficiently. Further, since the protrusion 13 can reinforce the intermediate convex portion 15, the rigidity of the tire 1 can be improved.

As shown in FIG. 5, the height H1 of the first recess 11A of each protrusion 13 from the bottom surface 11a is preferably 1.1 of the height H2 of the first recess 11A of the intermediate convex portion 15 from the bottom surface 11a. ~ 3.0 times. Further, the height H3 of the second recess 12A of each protrusion 13 from the bottom surface 12a is preferably 1.1 to 3.0 times the height H4 of the second recess 12A of the intermediate convex portion 15 from the bottom surface 12a. be. Such protrusions 13 can efficiently improve the heat dissipation and rigidity of the tire side portion 9.

FIG. 6 is a side view of the tire 18 of another embodiment. As shown in FIG. 6, the tire 18 of this embodiment has a concave-convex structure 20 on the tire side portion 19. The concavo-convex structure 20 of this embodiment includes a first concavo-convex portion 21, a second concavo-convex portion 22, a third concavo-convex portion 23, and a plurality of protrusions 24. In such a tire 18, the surface area of the tire side portion 19 can be increased by the first uneven portion 21, the second uneven portion 22, the third uneven portion 23, and the plurality of protrusions 24, and the tire side portion 19 can have a large surface area. The heat dissipation can be improved.

It is desirable that the first uneven portion 21 is located inside the tire radial direction a, and the first concave portion 21A and the first convex portion 21B are alternately arranged in the tire circumferential direction b. It is desirable that the second uneven portion 22 is outside the tire radial direction a of the first uneven portion 21, and the second concave portion 22A and the second convex portion 22B are alternately arranged in the tire circumferential direction b. It is desirable that the third uneven portion 23 is outside the tire radial direction a of the second uneven portion 22, and the third concave portion 23A and the third convex portion 23B are alternately arranged in the tire circumferential direction b.

The plurality of protrusions 24 of this embodiment include a plurality of first protrusions 24A arranged from the first uneven portion 21 to the second uneven portion 22, and a plurality of protrusions 24 arranged from the second uneven portion 22 to the third uneven portion 23. It includes the second protrusion 24B.

Such protrusions 24 can promote the generation of turbulent flow, and can further improve the heat dissipation of the tire side portion 19. Further, since the protrusion 24 can increase the rigidity of the tire side portion 19, the distortion of the tire side portion 19 can be reduced. Therefore, the tire 18 of the present embodiment can suppress the deterioration of the rubber due to the heat generation of the tire side portion 19 and the cracking of the rubber due to the distortion of the tire side portion 19, and improve the durability of the tire 18. Can be made to.

The plurality of first protrusions 24A of this embodiment are arranged from the first recess 21A to the second recess 22A, respectively. Further, the plurality of second protrusions 24B are arranged from the second recess 22A to the third recess 23A, respectively. Each of the first protrusions 24A and each second protrusion 24B is arranged at a position where they overlap each other in the tire circumferential direction b, for example.

In this embodiment, the first convex portion 21B and the third convex portion 23B are arranged at positions where they overlap each other in the tire circumferential direction b, but the first convex portion 21B and the third convex portion 23B are tires. They may be arranged at different positions in the circumferential direction b. In this case, it is desirable that the first convex portion 21B, the second convex portion 22B, and the third convex portion 23B are arranged at positions where the pitch is divided into three equal parts in the tire circumferential direction b.

It is desirable that the plurality of first protrusions 24A extend to the bottom surfaces of the first recess 21A and the second recess 22A, respectively. Further, it is desirable that the plurality of second protrusions 24B extend to the bottom surfaces of the second recess 22A and the third recess 23A, respectively. Since such a protrusion 24 also generates turbulent flow inside the first recess 21A, the second recess 22A, and the third recess 23A, the tire side portion 19 can be cooled more efficiently. The first protrusion 24A and the second protrusion 24B may be connected inside the second recess 22A.

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

A prototype tire having the basic structure of FIG. 1 and having the uneven structure of FIGS. 2 to 5 on the tire side portion was prototyped. Further, for comparison, a tire of Comparative Example 1 having the basic structure of FIG. 1 and having no uneven structure and a tire of Comparative Example 2 having an uneven structure not including protrusions were prototyped. Each of these prototype tires was mounted on a testing machine and tested for durability. The common specifications and test methods for each tire are as follows.

Tire size: 205 / 85R16
Mounting rim: 16 x 5.5J
Tire internal pressure: 600 kPa
Load Load: 17.58kN
Speed: 80km / h

<Durability>
Each test tire mounted on the test machine was run, and the mileage until the tire was damaged was measured. The result is displayed as an exponent with Comparative Example 1 as 100, and the larger the value, the better the durability.

The results of the test are as follows.
<Durability result (index)>
Comparative Example 1: 100
Comparative Example 2: 125
Example: 135

As a result of the test, it was confirmed that the tire of the example had a longer mileage until the tire was damaged and was excellent in durability as compared with the comparative example.

1 Tire 9 Tire side portion 10 Concavo-convex structure 11 First concavo-convex portion 11A First concave portion 11B First convex portion 12 Second concavo-convex portion 12A Second concave portion 12B Second protrusion 13 Protrusion

Claims (11)

A tire that has an uneven structure on the side of the tire.
The uneven structure is
A first uneven portion in which the first concave portion and the first convex portion are alternately arranged in the tire circumferential direction,
A second uneven portion in which the second concave portion and the second convex portion are alternately arranged in the tire circumferential direction on the outer side of the first uneven portion in the tire radial direction.
A plurality of protrusions arranged from the first uneven portion to the second uneven portion , and
Includes an intermediate convex portion extending in the tire circumferential direction between the first uneven portion and the second uneven portion.
The first convex portion and the second convex portion are arranged at positions that do not overlap each other in the tire circumferential direction.
tire.
The tire according to claim 1, wherein the plurality of protrusions are arranged from the first recess to the second recess, respectively. The tire according to claim 1 or 2, wherein the intermediate convex portion continuously extends in the tire circumferential direction.
The tire according to any one of claims 1 to 3, wherein each of the plurality of protrusions is arranged between the first convex portion and the second convex portion in the tire circumferential direction.
Before SL plurality of protrusions, respectively, arranged spaced apart on the middle protrusion, tire according to claim 1.
The tire according to claim 5, wherein the plurality of protrusions extend to the bottom surfaces of the first recess and the second recess, respectively. The sixth aspect of the present invention, wherein the height of the first concave portion of each of the protrusions from the bottom surface is 1.1 to 3.0 times the height of the first concave portion of the intermediate convex portion from the bottom surface. Tires. The tire according to any one of claims 1 to 7, wherein each protrusion extends in the radial direction of the tire. The tire according to any one of claims 1 to 8, wherein the length of each protrusion in the tire circumferential direction is smaller than the length of the first convex portion in the tire circumferential direction. A tire that has an uneven structure on the side of the tire.
The uneven structure is
A first uneven portion in which the first concave portion and the first convex portion are alternately arranged in the tire circumferential direction,
A second uneven portion in which the second concave portion and the second convex portion are alternately arranged in the tire circumferential direction on the outer side of the first uneven portion in the tire radial direction.
It includes a plurality of protrusions arranged from the first uneven portion to the second uneven portion.
The first convex portion and the second convex portion are arranged at positions that do not overlap each other in the tire circumferential direction.
The first recess and the second recess are recesses recessed inward in the tire axial direction from the surface of the tire side portion, respectively.
Tires. The uneven structure includes a third uneven portion outside the tire radial direction of the second uneven portion, in which the third concave portion and the third convex portion are alternately arranged in the tire circumferential direction.
The plurality of protrusions include a first protrusion arranged from the first uneven portion to the second uneven portion, and a second protrusion arranged from the second uneven portion to the third uneven portion. The tire according to any one of 1 to 10.

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