JPWO2016043191A1 - Pneumatic tire - Google Patents

Abstract

A decorative region having a side pattern is provided in a region including the tire maximum width position of the pneumatic tire on the sidewall surface of the pneumatic tire. The decorative region includes a ridge region provided with a plurality of ridges extending in one direction, and a strip region extending in a plurality of strips. Each of the belt-shaped regions includes a belt-shaped first smooth surface surrounded by the ridge region and a plurality of dimple-shaped first recesses surrounded by the first smooth surface and recessed from the first smooth surface. Is provided. The first smooth surface extends so as to incline from the tire radial direction to the tire circumferential direction. Each of the belt-like regions is arranged in a distributed manner in the tire circumferential direction, and the dimple-like first recesses are arranged in a row so that the belt-like region extends in the belt-like direction.

Description

  The present invention relates to a pneumatic tire, and more particularly to a pattern on a sidewall surface of a pneumatic tire.

In recent years, in order to improve the fuel consumption of a vehicle equipped with a pneumatic tire and improve the maximum speed of the vehicle, it is required to reduce the rolling resistance of the pneumatic tire. In order to reduce the rolling resistance of a pneumatic tire, various forms in which the structure of the pneumatic tire, the tread pattern design, and the like are changed have been proposed.
It has also been proposed to reduce the air resistance of a pneumatic tire during rolling in order to improve vehicle fuel efficiency and vehicle maximum speed. The air resistance of the pneumatic tire is affected by the unevenness of the tread pattern provided on the surface of the tread portion and the unevenness of the mark or pattern provided on the sidewall surface.

  For example, a plurality of dimple-shaped recesses are provided in a first region including a tire maximum width position on a sidewall surface of a pneumatic tire, and each of the recesses is arranged in one direction so as to cover each of the recesses. There is known a pneumatic tire provided with a plurality of linear troughs extending to the surface and subjected to serration processing (Patent Document 1).

JP 2012-106583 A

  In the pneumatic tire described above in which a plurality of dimple-shaped recesses are provided on the sidewall surface, the air resistance is reduced and the fuel consumption can be improved. However, the recesses are uniform in the decorative region on the sidewall surface. The total number of recesses is extremely large. Accordingly, it is necessary to provide a large number of convex portions on the tire vulcanization mold. For this reason, there is a problem that the processing cost of the tire vulcanization mold is increased, and the manufacturing cost of the tire is increased.

  Accordingly, an object of the present invention is to provide a pneumatic tire capable of effectively reducing the air resistance during rolling of the tire while suppressing the tire manufacturing cost by suppressing the processing cost of the tire vulcanizing mold. And

The present technology includes the following various types of pneumatic tires.
[Form 1]
A pneumatic tire,
The tread part,
Including a side part,
In the region including the tire maximum width position of the pneumatic tire on the sidewall surface of the side portion, a decorative region having a side pattern is provided,
The decorative area is
A ridge region provided with a plurality of ridges extending in one direction;
A belt-shaped first smooth surface that does not have a ridge surrounded by the ridge region, and a plurality of dimple-shaped first surfaces surrounded by the first smooth surface and recessed from the first smooth surface. 1 concave portion, the first smooth surface extends in the shape of a belt on the sidewall surface from the tire radial inner side toward the tire radial outer side, and the first smooth surface extends outward in the tire radial direction. A plurality of strip-like regions configured to extend from the tire radial direction to the tire circumferential direction when extending toward the tire,
The belt-shaped region is disposed on the sidewall surface dispersed in the tire circumferential direction,
The pneumatic tire according to claim 1, wherein the first recesses are arranged in a row so that the belt-like region extends along the belt-like direction.

[Form 2]
Among the plurality of belt-like regions, a plurality of pairs of belt-like regions adjacent to each other in the tire circumferential direction are arranged in a dispersed manner in the tire circumferential direction, and the belt-like regions of the set are mutually compared to other belt-like regions. The pneumatic tire according to aspect 1, which is provided at a close position.

[Form 3]
The occupying area in the tire circumferential direction of the row of first recesses included in two adjacent belt-like areas adjacent to each other in the tire circumferential direction in the set is partially overlapped on the tire circumference. Pneumatic tire.

[Form 4]
At least one of the end of the belt-like region on the inner side in the tire radial direction of the first smooth surface and the end of the belt-like region on the outer side in the tire radial direction of the first smooth surface is pointed toward the tire circumferential direction. The pneumatic tire according to any one of Embodiments 1 to 3, which has a tip pattern.

[Form 5]
The direction of the inclination of the plurality of belt-like regions with respect to the tire circumferential direction is the same as each other, and the plurality of belt-like regions are provided so as to form a spiral around the tire rotation axis. Pneumatic tire described in one.

[Form 6]
When the extending direction of the ridge and the extending direction of the first smooth surface in the ridge region are viewed from the inside to the outside in the tire radial direction, the extending direction of the ridge and the first smooth surface The pneumatic tire according to any one of Embodiments 1 to 5, wherein the extending direction is directed to different directions in the tire circumferential direction.

[Form 7]
In addition to the decorative area, a mark display area for displaying a mark is provided on the sidewall surface,
The mark display area includes a second smooth surface that does not have a ridge surrounding the mark, and a plurality of dimple-like shapes that are surrounded by the second smooth surface and are recessed from the second plane. A second recess,
The plurality of second recesses are arranged in a row, and the row of the second recesses extends from the inner side in the tire radial direction toward the outer side in the tire radial direction and is inclined from the tire radial direction to the tire circumferential direction. The pneumatic tire according to any one of Embodiments 1 to 6, which is provided as described above.

[Form 8]
The direction of the inclination of the plurality of belt-like regions with respect to the tire circumferential direction is the same as each other, and the plurality of belt-like regions are provided so as to form a spiral around the tire rotation axis,
The pneumatic tire according to aspect 7, wherein the second recesses are provided in a row in the spiral direction of the spiral shape.

[Form 9]
The pneumatic tire according to any one of aspects 1 to 8, wherein the first smooth surface protrudes outside the sidewall surface from the ridge top of the ridge region.

  According to the pneumatic tire described above, it is possible to effectively reduce the air resistance during rolling of the tire while suppressing the manufacturing cost of the tire by suppressing the processing cost of the tire vulcanizing mold.

It is a profile sectional view of an example of a pneumatic tire of this embodiment. It is the figure which showed an example of the surface of the side part of this embodiment. (A) is the enlarged view which expanded a part of pattern (pattern) of the sidewall surface of the tire shown in FIG. 2, (b) is the cross section along the XX line shown to (a) of FIG. FIG. It is a figure explaining the flow of the air around the sidewall surface in the tire of this embodiment. It is a figure explaining the air resistance by the pattern of the sidewall surface in the tire of this embodiment. It is a figure which shows an example of the arrangement | positioning form from which the strip | belt-shaped area | region used for the tire of this embodiment differs.

Hereinafter, the pneumatic tire of the present embodiment (hereinafter simply referred to as a tire) will be described in detail.
The pneumatic tire of this embodiment described below is applied to, for example, a tire for a passenger car, but can also be applied to a tire for a small truck or a tire for a bus / truck. The pneumatic tire of this embodiment described below is a passenger tire.

  In the following description, the tire width direction is a direction parallel to the rotation axis of the pneumatic tire. The outer side in the tire width direction is the side away from the tire center line CL representing the tire equatorial plane in the tire width direction. Further, the inner side in the tire width direction is a side closer to the tire center line CL in the tire width direction. The tire circumferential direction is a direction in which the pneumatic tire rotates around the rotation axis of the pneumatic tire. The tire radial direction is a direction orthogonal to the rotation axis of the pneumatic tire. The outer side in the tire radial direction refers to the side away from the rotation axis. The inner side in the tire radial direction refers to the side approaching the rotation axis.

(Tire structure)
FIG. 1 shows a profile cross-sectional view of an example of a tire 10 of the present embodiment. The tire 10 includes a tread portion 10T having a tread pattern, a pair of bead portions 10B, and a pair of bead portions 10B and a pair of side portions 10S that are connected to the tread portion 10T. Prepare.
The tire 10 includes a carcass ply layer 12, a belt layer 14, and a bead core 16 as a skeleton material. Around these skeleton materials, a tread rubber member 18, a side rubber member 20, and a bead filler rubber member 22. And a rim cushion rubber member 24 and an inner liner rubber member 26.

  The carcass ply layer 12 is made of a carcass ply material in which organic fibers are covered with rubber, which is wound between a pair of annular bead cores 16 to form a toroidal shape. The carcass ply material is wound around the bead core 16 and extends outward in the tire radial direction. A belt layer 14 composed of two belt members 14a and 14b is provided outside the carcass ply layer 12 in the tire radial direction. The belt layer 14 is a member in which a rubber is coated on a steel cord disposed at a predetermined angle, for example, 20 to 30 degrees with respect to the tire circumferential direction, and the lower belt material 14a is replaced with the upper belt material 14b. The width in the tire width direction is longer than that. The inclination directions of the steel cords of the two-layer belt materials 14a and 14b are opposite to each other. For this reason, belt material 14a, 14b is a crossing layer, and controls expansion of carcass ply layer 12 by the filled air pressure.

A tread rubber member 18 is provided on the outer side of the belt layer 14 in the tire radial direction, and side rubber members 20 are connected to both ends of the tread rubber member 18 to form a side portion 10S. A rim cushion rubber member 24 is provided at the inner end in the tire radial direction of the side rubber member 20 and is in contact with a rim on which the tire 10 is mounted. The bead core 16 is sandwiched between the portion of the carcass ply layer 12 before being wound around the bead core 16 and the portion of the carcass ply layer 12 that is wound around the bead core 16 on the outer side in the tire radial direction. Thus, a bead filler rubber member 22 is provided. An inner liner rubber member 26 is provided on the inner surface of the tire 10 facing the tire cavity region filled with air surrounded by the tire 10 and the rim.
In addition, the tire 10 includes a two-layer belt cover layer 30 that covers the belt layer 14 from the outer side in the tire radial direction of the belt layer 14 and is coated with an organic fiber or a steel cord with rubber. Further, a bead reinforcing material may be provided between the carcass layer 12 wound around the bead core 16 and the bead filler rubber member 22. The tire structure of the present embodiment is as described above, but the tire structure is not particularly limited, and a known tire structure can be applied. Further, the tread pattern in the tread portion 10T of the tire 10 of the present embodiment is not particularly limited.

(Sidewall pattern)
FIG. 2 is a diagram illustrating an example of a sidewall surface of the side portion 10S. Fig.3 (a) is the enlarged view which expanded a part of pattern (pattern) of the sidewall surface of the side part 10S of the tire shown in FIG. 2, FIG.3 (b) is shown in Fig.3 (a). It is sectional drawing along XX.
An information display area 32, a mark display area 33, and a decoration area 34 are provided on the sidewall surface of the tire of the present embodiment. The mark of the combination of the letter “Y” and the letter “YOKOHAMA” in FIG. 2 is a registered trademark.
Information such as a tire size and a standard of the tire 10 is written in the information display area 32. In the mark display area 33, a brand name of the tire 10 or a mark such as a tire manufacturer is displayed.

The decoration region 34 is provided in a region including the tire maximum width position of the tire 10. The decoration area 34 is provided with the following pattern, which is a side pattern of the side portion 10S. The decoration region 34 includes a ridge region 36 and a strip region 38.
The ridge region 36 is a region provided with a plurality of ridges 36a extending in one direction. For example, by performing serration processing on the inner surface of the vulcanizing mold of the tire 10, ridge-shaped irregularities that become the ridge regions 36 are formed on the inner surface of the mold. As a result, the ridge 36a is formed. (In FIG. 2, the line of the ridge 36a in the ridge region 36 is blacked out and cannot be identified.)

A plurality of strip regions 38 are provided on the sidewall surface. The belt-like region 38 includes a belt-like first smooth surface 39 and a first recess 40 that do not have a ridge surrounded by the ridge region 36. A plurality of first recesses 40 are provided in a circular dimple shape. The circular shape of the first recess 40 is a perfect circle shape or an elliptical shape. As shown in FIG. 3B, the first recess 40 is surrounded by the first smooth surface 39 and is recessed from the first smooth surface 39 toward the inner side in the tire width direction (the tire cavity region side). Is provided. As shown in FIGS. 2 and 3A, the first smooth surface 39 extends in a band shape on the sidewall surface from the inner side in the tire radial direction toward the outer side in the tire radial direction, and the first smooth surface 39. When extending toward the outer side in the tire radial direction, the tire extends from the tire radial direction to the tire circumferential direction.
The belt-like regions 38 are distributed on the sidewall surface in the tire circumferential direction. The dimple-shaped first recesses 40 form a row, and this row extends along the direction in which the belt-like region 38 extends in a belt shape. In the present embodiment, the first recesses 40 are preferably arranged in one row, but are not limited to one row, and may be two or more rows.

  With such a pattern of the decoration region 34, the air resistance at the time of rolling of the tire can be efficiently reduced even if the number of the first dimple-shaped concave portions 40 is smaller than that of the conventional one. Accordingly, it is possible to efficiently suppress the air resistance during rolling of the tire while suppressing the processing cost of the tire vulcanizing mold and consequently the manufacturing cost of the tire.

FIG. 4 is a diagram illustrating the flow of air around the sidewall surface in the tire 10.
When the tire 10 assembled to the rim R is run in the direction of arrow F, there is a speed difference between the air flow slightly away from the sidewall surface and the air flow near the sidewall surface. As the running speed of the tire increases, the air flow A on the sidewall surface spirals and delaminates when it exceeds a certain limit. This peeling phenomenon remarkably increases the air resistance of the sidewall. In order to make the peeling phenomenon difficult to occur, that is, in order to position the peeling phenomenon downstream, when the row of the first recesses 40 extends outward in the tire radial direction, the row extends from the tire radial direction to the tire circumference. Along the extending direction of the band-shaped region 38 extending so as to incline in the direction. For this reason, in the tire that rotates and moves, the peeling phenomenon acts as downstream as possible in the traveling direction as much as possible in the same manner as the dimple-like recesses provided uniformly in the decorative region on the sidewall surface. For this reason, it is possible to reduce the air resistance by positioning the spiral flow generation position on the downstream side.
On the other hand, since the number of the first recesses 40 of the present embodiment is provided in the belt-like region 38, it is smaller than the total number of dimple-like recesses provided uniformly in the decoration region as in the prior art. For this reason, the processing cost required for preparation of the convex part of the tire vulcanization mold corresponding to the concave part can be suppressed. Thereby, the manufacturing cost of a tire can be held down. Therefore, the tire of this embodiment can effectively reduce the air resistance during tire rolling while suppressing the manufacturing cost of the tire.

  The belt-like regions 38 of the tire 10 according to the present embodiment may be uniformly distributed and spaced apart from each other by a certain distance on the tire circumference, but the following embodiments are preferable. That is, in the plurality of belt-like regions, a plurality of sets of belt-like regions adjacent to each other in the tire circumferential direction are arranged in a plurality dispersed in the tire circumferential direction. At this time, the pair of band-like regions are provided at positions closer to each other than the other band-like regions. In this embodiment, since the plurality of rows of the first recesses 40 are set corresponding to the set of adjacent belt-like regions, the set of the plurality of rows is accompanied by the movement of the tire as described above. The separation phenomenon in the air flow around the sidewall surface that occurs can be efficiently located downstream.

  When the belt-like regions 38 form a set, the occupied region in the tire circumferential direction of the row of the first concave portions 40 included in two adjacent belt-like regions adjacent to each other in the tire circumferential direction of the set is It is preferable that it overlaps partially. In the set of belt-like regions 38, the first recesses 40 are not interrupted on the tire circumference, so that when the tire rolls, the flow of air around the sidewall surface is a row of the first recesses 40 in the belt-like regions 38. By touching, the peeling phenomenon can be moved to the downstream side more efficiently.

In the present embodiment, the end portion of the belt-like region 38 on the inner side in the tire radial direction of the first smooth surface 39 (the end portion in the inclined direction inclined from the tire radial direction to the tire circumferential direction), and the tire diameter of the first smooth surface 39. It is preferable that at least one of the end portions (end portions in the inclined direction inclined from the tire radial direction to the tire circumferential direction) of the band-like region 38 on the outer side in the direction has a pointed tip pattern in the tire circumferential direction. In this case, as shown in FIG. 5, the rolling of the tire (rotation R ₁ direction in FIG. 5), when viewed first smooth surface 39 as a reference, the flow of air flows as straight arrows. Therefore, the air flow can be rectified and the air resistance can be reduced by making the end portion of the first smooth surface 39 a pointed tip pattern in the tire circumferential direction. In particular, the end portions of the belt-shaped regions 38 on the inner side and the outer side in the tire radial direction of the first smooth surface 39 are formed as pointed tip patterns in the tire circumferential direction, so that the tire mounting direction is reversed, as shown in FIG. Even in the case of rotating in the R2 direction shown in FIG. ₂ , the air flow can be rectified and the air resistance can be reduced. FIG. 5 is a diagram for explaining the air resistance due to the pattern of the sidewall surface in the tire of the present embodiment. The mark of the combination of the letters “Y” and “YOKOHAMA” in FIG. 5 is registered. Trademark.
The tip pattern pointed in the tire circumferential direction includes a pattern in which the leading edge is rounded with a curvature radius of 2.0 mm or less, in addition to a pattern in which the leading edge forms an acute angle.

  In the present embodiment, each of the plurality of belt-like regions 38 has the same inclination direction inclined from the tire radial direction to the tire circumferential direction, and the plurality of belt-like regions 38 are provided so as to form a spiral around the tire rotation axis. It is preferable that the air flow can be rectified. However, as long as the peeling phenomenon in the air flow around the sidewall surface shown in FIG. 4 caused by the movement of the tire 10 can be moved downstream, as shown in FIG. The direction of the inclination with respect to the circumferential direction may be different. FIG. 6 is a diagram showing an example of a different arrangement form of the band-like regions 38. Also in this case, the occupied area in the tire circumferential direction of the first recess 40 included in the C-shaped band-shaped area 38 shown in FIG. 6 is not shown in FIG. 6, but partially on the tire circumference. The overlapping is preferable from the viewpoint of more efficiently moving the peeling phenomenon downstream.

  Further, when the extending direction of the ridge 36a in the ridge region 36 and the extending direction of the first smooth surface 39 are viewed from the inner side to the outer side in the tire radial direction, the extending direction of the ridge 36a and the first smoothing surface The extending direction of the surface 39 is preferably directed in different directions in the tire circumferential direction (ie, directed in a clockwise direction and a counterclockwise direction) from the viewpoint of making the first smooth surface 39 stand out. When the first smooth surface 39 stands out in the decoration area 34, a person viewing the sidewall surface moves his / her line of sight along the inclination direction of the first smooth surface 39, and the mark in the mark display area 33 is displayed. Can be easily recognized. Further, since the spiral shape of the first smooth surface 39 and the row of the first concave portions 40 surrounded by the first smooth surface 39 is conspicuous, the air flow is rectified and the air resistance is reduced. It is easy to be recognized as a tire.

  In the present embodiment, as shown in FIG. 2, the mark display area 33 is surrounded by the second smooth surface 42 having no ridge surrounding the mark and the second smooth surface 42, and the second smooth surface 42. A plurality of dimple-shaped second recesses 44 provided so as to be recessed from the surface 42, the plurality of second recesses 44 being arranged in a row, and the row of the second recesses 44 is a tire diameter. It is preferably provided so as to extend from the inner side in the tire direction toward the outer side in the tire radial direction and to be inclined from the tire radial direction to the tire circumferential direction. Specifically, the direction of the rows of the second recesses 44 facing the tire circumferential direction is preferably the same as the direction of the rows of the first recesses 40 facing the tire circumferential direction. That is, the second recesses 44 are preferably provided in a row in the spiral direction of the band-like region 38 extending in a spiral shape and the first recess 40. In the mark display area 33, the mark portion is provided by the second smooth surface 42 so that the mark can be easily visually recognized. However, the 2nd smooth surface 42 makes it easy to produce the peeling phenomenon in the air flow mentioned above. For this reason, it is preferable that the dimple-shaped second recesses 44 are arranged in a row in the mark display area 33. At this time, the row of the second recesses 44 extends from the inner side in the tire radial direction toward the outer side in the tire radial direction so that the range in which the air flow contacts the row of the second recesses 44 is increased. From the direction to the tire circumferential direction.

  Further, as shown in FIG. 3B, the first smooth surface 39 of the present embodiment protrudes from the top of the ridge 36a in the ridge region 36 to the outside of the sidewall surface. This is preferable in terms of suppressing the resistance of air flow that is likely to occur. Thereby, the function of the 1st recessed part 40 provided so that it may be enclosed by the 1st smooth surface 39, ie, the generation | occurrence | production position of the peeling phenomenon in the flow of air, can be efficiently moved downstream.

The tire 10 may be provided with the decoration region 34 on each of the sidewall surfaces on both sides in the tire width direction, or may be provided with the decoration region 34 only on one side wall surface. Moreover, when the decoration area | region 34 is provided in the sidewall surface of both sides, it is preferable that the direction extended in the tire circumferential direction of the strip | belt-shaped area | region 38 is the direction of the same tire circumferential direction in the sidewall surface of both sides. In addition, the direction extending in the tire circumferential direction of the belt-like region 38 when the tire 10 is mounted on a wheel on one side of the vehicle, for example, the left wheel is a spiral shape corresponding to the direction of the rotational direction rotating in the forward direction of the vehicle. On the other hand, the direction extending in the tire circumferential direction of the belt-like region 38 when the tire 10 is attached to the wheel on the other side of the vehicle, for example, the right wheel, corresponds to the direction of the rotational direction rotating in the reverse direction of the vehicle. It may be a spiral shape. Even in this case, in the belt-like regions 38 of the tires 10 on both sides, the peeling phenomenon in the air flow moves downstream by the action of the first recess 40.
Each of the first recess 40 and the second recess 44 of the tire 10 has a circular opening shape, but is not limited to a circular opening shape, and may be a polygonal shape. Moreover, the 1st recessed part 40 and the 2nd recessed part 44 are not limited to the shape recessed in circular arc shape in the depth direction of a recessed part, The shape recessed in the rectangular shape may be sufficient.

(Examples, comparative examples, conventional examples)
In order to confirm the effect of this embodiment, various patterns were produced on the sidewall surface, and the manufacturing cost and air resistance of the tire were examined. The tire size was 195 / 65R15 91H, the front and rear wheel air pressure was 240 kPa, and a 15 × 6J rim was used.

The air resistance was measured by installing it on a vehicle (minivan type) and examining the fuel consumption. Specifically, the fuel consumption per predetermined distance was calculated from the fuel consumption by running 500 laps at a speed of 100 km / h on a 2 km round course. The higher the fuel consumption, the less air resistance.
On the other hand, the manufacturing cost was estimated by estimating the production cost of the mold. Specifically, the openings of the first recess 40 and the second recess 44 were circular, the diameter thereof was 3.6 mm, and the depth was adjusted to 0.7 mm. The manufacturing cost of the tire is affected by the production cost of the convex portions on the inner surface of the mold corresponding to the first concave portion 40 and the second concave portion 44.

The produced tire is 11 types, a conventional example, a comparative example, and Examples 1-9.
The conventional example includes a sidewall surface that does not have the first recess 40 and the second recess 44 among the sidewall surfaces shown in FIG.
The comparative example has a uniform dimple-like recess on the entire decoration region on the sidewall surface.
Examples 1 to 8 have the first recess 40 on the sidewall surface shown in FIG. 2, but do not have the second recess 44. Example 9 has the 1st recessed part 40 and the 2nd recessed part 44 in the sidewall surface shown in FIG.
In Tables 1 and 2, “Inclination direction” and “Inclination direction” in “Inclination direction of first recess” is the direction in the tire circumferential direction that is the same as the rotational direction when the tire advances in the forward direction, or is the opposite? Represents. In the table, “the same direction as the rotational direction” means that when the first row of recesses advances from the outer side to the inner side in the tire radial direction, the direction in which the row of first recesses extends in two directions in the tire circumferential direction. This means that the direction of rotation when traveling in the direction and the direction in the tire circumferential direction match. “The direction opposite to the rotational direction” means that when the first row of recesses advances from the outer side to the inner side in the tire radial direction, the direction in which the first row of recesses extends in two directions in the tire circumferential direction It is the direction opposite to the direction of rotation when moving in the direction. In addition, the “spiral shape” in the embodiment means that the arrangement direction of the band-shaped region 38 and the first recess 40 is arranged in a spiral shape as shown in FIG. It means that they are arranged in a shape as shown in FIG.
“Yes” in “Presence / absence of belt-shaped region groups” in Tables 1 and 2 indicates that two adjacent belt-shaped regions 38 form a group, and a plurality of these groups are distributed on the tire circumference. “None” means a form in which the belt-like regions 38 do not form a set and are evenly distributed on the tire circumference one by one.
In Tables 1 and 2, “existence of pointed tip pattern in the belt-like area” means “when present” means that the leading edge is an acute angle of 10 degrees, while “not” means that the leading edge is curved. It means that it is rounded with a radius of 3.5 mm.

  In Tables 1 and 2 below, the fuel consumption and the manufacturing cost are shown as indexes with the conventional example as 100. It means that the higher the fuel efficiency index is, the better the fuel efficiency is (the amount of fuel required to travel a certain distance is reduced), and the air resistance is reduced. A lower manufacturing cost index means a higher manufacturing cost.

From Table 1 above, in terms of fuel efficiency, Examples 1 to 8 are substantially equivalent to the comparative example (the amount of fuel required for traveling over a certain distance is substantially equivalent), while the manufacturing cost can be greatly reduced. . The decrease in fuel consumption by 1 or 2 points is extremely small and is at an acceptable level.
Moreover, although the manufacturing cost in Examples 1-9 rises compared with a prior art example (an index becomes low), the increase is very low compared with a comparative example.

  As mentioned above, although the pneumatic tire of this invention was demonstrated in detail, this invention is not limited to the said embodiment and Example, In the range which does not deviate from the main point of this invention, you may make a various improvement and change. Of course.

DESCRIPTION OF SYMBOLS 10 Pneumatic tire 10T Tread part 10B Bead part 10S Side part 12 Carcass ply layer 14 Belt layer 16 Bead core 18 Tread rubber member 20 Side rubber member 22 Bead filler rubber member 24 Rim cushion rubber member 26 Inner liner rubber member 28 Bead reinforcement member 30 Belt Cover layer 32 Information display area 33 Mark display area 34 Decoration area 36 Ridge area 38 Band-shaped area 39 First smooth surface 40 First recess 42 Second smooth surface 44 Second recess

Claims (9)

A pneumatic tire,
The tread part,
Including a side part,
In the region including the tire maximum width position of the pneumatic tire on the sidewall surface of the side portion, a decorative region having a side pattern is provided,
The decorative area is
A ridge region provided with a plurality of ridges extending in one direction;
A belt-shaped first smooth surface that does not have a ridge surrounded by the ridge region, and a plurality of dimple-shaped first surfaces surrounded by the first smooth surface and recessed from the first smooth surface. 1 concave portion, the first smooth surface extends in the shape of a belt on the sidewall surface from the tire radial inner side toward the tire radial outer side, and the first smooth surface extends outward in the tire radial direction. A plurality of strip-like regions configured to extend from the tire radial direction to the tire circumferential direction when extending toward the tire,
The belt-shaped region is disposed on the sidewall surface dispersed in the tire circumferential direction,
The pneumatic tire according to claim 1, wherein the first recesses are arranged in a row so that the belt-like region extends along the belt-like direction.   Among the plurality of belt-like regions, a plurality of pairs of belt-like regions adjacent to each other in the tire circumferential direction are arranged in a dispersed manner in the tire circumferential direction, and the belt-like regions of the set are mutually compared to other belt-like regions. The pneumatic tire according to claim 1, which is provided at a close position.   The occupied area of the tire circumferential direction of the row | line | column of the 1st recessed part contained in the two adjacent strip | belt-shaped area | regions mutually adjacent | abutted mutually in a tire circumferential direction among the said groups has overlapped on the tire circumference partially. Pneumatic tires.   At least one of the end of the belt-like region on the inner side in the tire radial direction of the first smooth surface and the end of the belt-like region on the outer side in the tire radial direction of the first smooth surface is pointed toward the tire circumferential direction. The pneumatic tire according to any one of claims 1 to 3, wherein the pneumatic tire has a tip pattern.   The direction of the inclination with respect to the tire circumferential direction of the plurality of belt-like regions is the same as each other, and the plurality of belt-like regions are provided so as to form a spiral around the tire rotation axis. The pneumatic tire according to item 1.   When the extending direction of the ridge and the extending direction of the first smooth surface in the ridge region are viewed from the inside to the outside in the tire radial direction, the extending direction of the ridge and the first smooth surface The pneumatic tire according to any one of claims 1 to 5, wherein the extending directions are directed in different directions in the tire circumferential direction. In addition to the decorative area, a mark display area for displaying a mark is provided on the sidewall surface,
The mark display area includes a second smooth surface that does not have a ridge surrounding the mark, and a plurality of dimple-like shapes that are surrounded by the second smooth surface and are recessed from the second plane. A second recess,
The plurality of second recesses are arranged in a row, and the row of the second recesses extends from the inner side in the tire radial direction toward the outer side in the tire radial direction and is inclined from the tire radial direction to the tire circumferential direction. The pneumatic tire according to claim 1, which is provided as described above. The direction of the inclination of the plurality of belt-like regions with respect to the tire circumferential direction is the same as each other, and the plurality of belt-like regions are provided so as to form a spiral around the tire rotation axis,
The pneumatic tire according to claim 7, wherein the second recesses are provided in a row in the spiral direction of the spiral shape.   The pneumatic tire according to any one of claims 1 to 8, wherein the first smooth surface protrudes outside the sidewall surface from the ridge top of the ridge region.

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