JP5886532B2 - tire - Google Patents

Description

  The present invention relates to a tire in which a plurality of turbulent flow generation projections extending along a tire radial direction are provided on a part of a tire side portion.

  Conventionally, in a pneumatic tire (hereinafter abbreviated as a tire as appropriate) mounted on a passenger vehicle, a construction vehicle, a truck, a bus, or the like, a tire diameter is suppressed in order to suppress a temperature rise in a tire side portion (tread end to bead portion). A structure in which fin-like turbulent flow generation protrusions extending in the direction are provided on the surface of the tire side portion is used (for example, Patent Document 1).

  According to such a tire, the air flowing along the surface of the tire side portion as the tire rolls is disturbed when the turbulent flow generation protrusion is overcome. That is, the turbulent flow generation projection generates turbulent flow on the surface of the tire side portion. When the generated turbulent flow hits the surface of the tire side portion, the tire side portion can be efficiently cooled.

International Publication No. 2007/032405 (page 6-7, Fig. 2)

  By the way, in tires installed on large vehicles such as construction vehicles and trucks and buses (hereinafter referred to as heavy-duty tires), the tires in the tread portion in the tire radial direction are compared to tires mounted on passenger vehicles (hereinafter referred to as passenger vehicle tires). The thickness along the line is thick. For this reason, the calorific value of the tread portion in the heavy duty tire is larger than the calorific value of the tread portion in the passenger car tire.

  In order to suppress the temperature rise of the tread portion of such a heavy load tire, a method of extending the turbulent flow generation projection provided on the tire side portion to the tread portion is conceivable. However, the diameter of the heavy duty tire is larger than that of the passenger car tire. Therefore, it is necessary to lengthen the length of the turbulent flow generation projection in the tire radial direction. In this case, since the volume of the turbulent flow generation projection itself increases, the turbulent flow generation projection itself generates heat, and the tire cooling effect is reduced.

  Therefore, an object of the present invention is to provide a tire that can improve the cooling effect of the tire while more reliably suppressing the temperature rise of the tread portion when the turbulent flow generation projection is provided.

  In order to solve the above-described problems, the present invention has the following features. First, a first feature of the present invention is that a tread end (tread end 51) located outside a tread width direction (tread width direction TW) of a tread portion (tread portion 50) in contact with a road surface is a bead portion (bead portion 10). For generating turbulent flow that protrudes from the tire side portion toward the outer side in the tread width direction and extends along the tire radial direction (tire radial direction TR) at a part of the tire side portion (tire side portion 60) up to A tire (heavy load tire 1) provided with a plurality of protrusions (turbulent flow generating protrusions 70), wherein the turbulent flow generating protrusions have a tire cross-sectional height (tire cross-sectional height from the tread end to the tread end). Is provided only within a range (tread side portion 60A) up to a position radially inward in the tire radial direction (tread innermost position P) by a length of ¼ with respect to (TH). When the height is h, the width orthogonal to the extending direction of the turbulent flow generation protrusion is w, and the distance between the turbulent flow generation protrusions adjacent in the tire circumferential direction is d, the relationship d> h> w is satisfied. This is the gist.

  According to such a feature, the turbulent flow generation projection is a tread end and a range from the tread end to a position radially inward in the tire radial direction by a quarter of the tire cross-section height (hereinafter, tread side portion). Are provided only inside and satisfy the relationship of d> h> w. According to this, since the turbulent flow generated by the turbulent flow generation projection hits the surface of the tread side portion, the tread side portion can be efficiently cooled. For this reason, since increase of the heat storage amount of a tread part can be suppressed and deterioration of a tread part can be controlled, the durability of a tread part can be improved more certainly.

  Further, since the turbulent flow generation projection is not provided on the tire side portion (hereinafter referred to as a sidewall portion) on the inner side in the tire radial direction than the tread side portion, the heat storage amount of the turbulent flow generation projection does not increase. The side portion can be efficiently cooled. Furthermore, the distance from the tire rotation axis of the tread side portion is far from the tire rotation axis of the sidewall portion. For this reason, the rotational speed of the tread side part is faster than the rotational speed of the sidewall part. Therefore, the tread side portion can be further efficiently cooled.

  A second feature of the present invention relates to the first feature of the present invention, and is summarized in that a height h of the turbulent flow generation projection is 3 to 10 mm.

  A third feature of the present invention relates to the first or second feature of the present invention, in a cross section perpendicular to the extending direction of the turbulent flow generation projection, at least one side surface of the turbulent flow generation projection, The gist of the present invention is that the angle formed by the surface of the tire side portion is larger than 90 degrees.

  A fourth feature of the present invention relates to the third feature of the present invention, and is summarized in that a cross-sectional shape perpendicular to the extending direction of the turbulent flow generation projection is trapezoidal.

  According to the characteristics of the present invention, when a turbulent flow generation projection is provided, it is possible to provide a tire that can improve the cooling effect of the tire while more reliably suppressing the temperature rise of the tread portion.

FIG. 1 is a perspective view showing a part of a heavy duty tire 1 according to the present embodiment. FIG. 2 is a cross-sectional view in the tread width direction TW of the heavy duty tire 1 according to the present embodiment. FIG. 3 is a perspective view showing a part of the turbulent flow generation projection 70 according to the present embodiment. FIG. 4 is a cross-sectional view of the turbulent flow generation projection 70 according to the present embodiment. FIG. 5 is a perspective view showing a part of the heavy duty tire A according to the first modification. FIG. 6 is a perspective view showing a part of the turbulent flow generation projection 70B according to the second modification. FIG. 7 is a cross-sectional view of a turbulent flow generation projection according to another embodiment. FIG. 8 is a cross-sectional view of a turbulent flow generation projection according to another embodiment. FIG. 9 is a cross-sectional view of a turbulent flow generation projection according to another embodiment.

  Next, an embodiment of a heavy duty tire according to the present invention will be described with reference to the drawings. Specifically, (1) overall configuration of heavy load tire, (2) detailed configuration of turbulent flow generation projection, (3) comparative evaluation, (4) action / effect, (5) modification example, (6) other The embodiment will be described.

  In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic and ratios of dimensions and the like are different from actual ones.

  Accordingly, specific dimensions and the like should be determined in consideration of the following description. Moreover, the part from which the relationship and ratio of a mutual dimension differ also in between drawings may be contained.

(1) Overall Configuration of Heavy Load Tire First, the overall configuration of the heavy load tire 1 according to the present embodiment will be described with reference to the drawings. FIG. 1 is a perspective view showing a part of a heavy duty tire 1 according to the present embodiment. FIG. 2 is a cross-sectional view of the heavy duty tire 1 according to the present embodiment in the tread width direction TW and the tire radial direction TR. The heavy load tire 1 may be filled with an inert gas such as nitrogen gas instead of air.

  As shown in FIGS. 1 and 2, the heavy duty tire 1 is a tire mounted on a large vehicle such as a construction vehicle tire (ORR) or a truck / bus tire (TBR). Specifically, the heavy duty tire 1 includes a bead portion 10, a carcass layer 20, an inner liner 30, a belt layer 40, and a tread portion 50.

  The bead portion 10 is in contact with a rim (not shown). The bead unit 10 includes at least a bead core 11 and a bead filler 13. The bead core 11 is a core of the bead unit 10. The bead filler 13 is provided between the carcass layers 20 where the bead core 11 is folded back, and suppresses deformation of the bead portion 10.

  The carcass layer 20 forms a skeleton of the heavy duty tire 1. The carcass layer 20 is formed in a toroidal shape in the cross section in the tread width direction. In addition, the carcass layer 20 has the bead core 11 folded back from the inner side to the outer side in the tread width direction TW.

  The inner liner 30 is formed of a highly airtight rubber layer that serves as a tube. The inner liner 30 is provided inside the carcass layer 20.

  The belt layer 40 retains the shape of the heavy load tire 1 and reinforces the tread portion 50. The belt layer 40 is provided outside the carcass layer 20 in the tire radial direction TR. A plurality of belt layers 40 are provided, and each belt layer 40 is provided along the tire circumferential direction TC.

  The tread portion 50 is in contact with the road surface. The tread portion 50 is provided outside the belt layer 40 in the tire radial direction TR.

  A tire side portion 60 is provided outside the heavy load tire 1 in the tread width direction TW. In the present embodiment, the tire side portion 60 is a region from the tread end 51 on the tire radial direction outer side of the tread portion 50 to the bead portion 10 (intermediate portion of the bead filler 13 in the tire radial direction TR) in the tread width direction TW cross section. It is. The tread end 51 is an intersection of an extension line of the surface of the tread portion 50 (surface in contact with the road surface) and an extension line of the surface of the tire side portion 60 (tread side portion 60A) in the tread width direction TW cross section.

  A part of the tire side portion 60 is provided with a turbulent flow generation projection 70 that protrudes outward from the tire side portion 60 in the tread width direction TW.

(2) Configuration of Turbulent Flow Generation Projection Next, the configuration of the above-described turbulent flow generation projection 70 will be described with reference to FIGS. FIG. 3 is a perspective view showing a part of the turbulent flow generation projection 70 according to the present embodiment. FIG. 4 is a cross-sectional view of the turbulent flow generation projection 70 according to the present embodiment.

  As shown in FIG. 1, a plurality of turbulent flow generation projections 70 are provided at predetermined intervals in the tire circumferential direction TC. The turbulent flow generation projection 70 continuously extends linearly along the tire radial direction. The turbulent flow generation projection 70 extends from the tread end 51 to a position radially inward of the tire radial direction from the tread end 51 to the tire cross-section height TH (hereinafter, tread innermost position P). It is provided in a range (hereinafter, tread side portion 60A). That is, the turbulent flow generation projection 70 is provided in a range from the tread end 51 to the tread innermost position P. In the present embodiment, the outer end portion in the tire radial direction of the turbulent flow generation projection 70 is located on the inner side in the tire radial direction from the tread end 51. The outer end portion in the tire radial direction of the turbulent flow generation projection 70 may be at the same position as the tread end 51.

  Here, the tire cross-sectional height TH refers to the tire cross-sectional height in the dread width direction cross-section defined by JATMA (Japan Automobile Tire Association). That is, the tire cross-sectional height TH is a height from the bead inner end 15 located on the innermost side in the tire radial direction TR of the bead part 10 to the outermost position 53 on the tread located on the outermost side in the tire radial direction TR of the tread part 50. It shows.

  Moreover, the tire side part 60 mentioned above is comprised by 60 A of tread side parts, and the side wall part 60B. As described above, the tread side portion 60A is a region from the tread end 51 to the innermost position P of the tread. On the other hand, the sidewall portion 60B is a region from the tread innermost position P to the bead portion 10 (intermediate portion of the bead filler 13 in the tire radial direction TR). The tread innermost position P is located on the surface of the tire side portion 60 in the tread width direction TW cross section. Specifically, the innermost position P of the tread is located at the boundary between the tread side portion 60A and the sidewall portion 60B. The tread innermost position P is located on the inner side in the tire radial direction from the tread end 51 by a length of 1/4 of the tire cross-section height TH along the tire radial direction in the tread width direction TW cross section.

  As shown in FIGS. 2 and 3, the turbulent flow generation projection 70 includes a pair of side surfaces 71 and an upper surface 72 connected to the pair of side surfaces 71. In a cross section (see FIG. 4) orthogonal to the extending direction of the turbulent flow generation projection 70 (that is, the tire radial direction), at least one side surface 71 of the turbulent flow generation projection 70 and the surface of the tread side portion 60A The formed angle θ is larger than 90 degrees. In this embodiment, the cross-sectional shape orthogonal to the extending direction of the turbulent flow generation projection 70 is a trapezoid.

  When the height of the turbulent flow generation projection 70 is h, the width perpendicular to the extending direction of the turbulent flow generation projection 70 is w, and the interval between the turbulent flow generation projections 70 adjacent to the tire circumferential direction TC is d, The relationship d> h> w is satisfied. The width w of the turbulent flow generation projection 70 indicates the widest width (the width of the lower side in the embodiment) along the extending direction of the turbulent flow generation projection 70.

  Specifically, the height h of the turbulent flow generation projection 70 is 3 to 10 mm. The width w of the lower side of the turbulent flow generation projection 70 is 2 to 8 mm. Further, when the height of the turbulent flow generation projection 70 is h, the width of the turbulent flow generation projection 70 is w, and the pitch of the turbulent flow generation projections 70 adjacent to the tire circumferential direction TC is “p”, 1 0.0 ≦ p / h ≦ 50.0 and 1.0 ≦ (p−w) /w≦100.0 are satisfied. Note that the pitch p indicates the distance from the center of one turbulent flow generation projection 70 to the center of the adjacent turbulent flow generation projection 70 at the center in the extending direction of the turbulent flow generation projection 70.

(3) Comparative Evaluation Next, in order to further clarify the effect of the present invention, comparative evaluation performed using heavy load tires according to the following comparative examples and examples will be described. Specifically, (3-1) Configuration of each heavy load tire and (3-2) evaluation result will be described. In addition, this invention is not limited at all by these examples.

(3-1) Configuration of Each Heavy Load Tire First, the heavy load tires according to Comparative Examples 1 and 2 and Examples will be briefly described. The data on the heavy duty tire was measured under the following conditions.

・ Tire size: 445 / 95R25
・ Rim size: 11.25 / 2.0
・ Internal pressure condition: Normal internal pressure (900 kpa)
・ Load condition: Normal load (7.4 ton)

  The heavy load tire according to Comparative Example 1 is not provided with a turbulent flow generation projection. In the heavy load tire according to the comparative example 2, the turbulent flow generation protrusion is provided only in the vicinity of the position of the tire maximum width. The heavy duty tire according to the example is the tire described in the above-described embodiment (see FIGS. 1 to 4). The configuration of each turbulent flow generation projection is as shown in Table 1.

(3-2) Evaluation Results After traveling for 12 hours at a speed of 41 km / h (constant speed) in a vehicle equipped with each heavy load tire, the temperature of the tread portion of each heavy load tire was measured. In Table 1, the temperature of the tread portion of the heavy load tire according to Comparative Example 1 is defined as a reference value (0), and the temperature difference of the other heavy load tires with respect to the reference value is shown.

  As a result, it was found that the heavy load tire according to the example has a reduced temperature of the tread portion, that is, the tread portion can be cooled, as compared with the heavy load tire according to Comparative Examples 1 and 2.

(4) Action / Effect In the embodiment, the turbulent flow generation projection 70 is provided only in the tread side portion 60A. According to this, as compared with the case where the turbulent flow generation projection 70 is provided on the entire tire side portion 60, the volume of the turbulent flow generation projection itself is reduced. Therefore, the turbulent flow generation projection 70 itself hardly generates heat, and the cooling effect of the heavy load tire 1 can be improved.

  The turbulent flow generation projection 70 is provided only in the tread side portion 60A and satisfies the relationship d> h> w. According to this, turbulent flow can be generated in the tread side portion 60 </ b> A by the turbulent flow generating projection 70 having a volume such that the heat generated by the turbulent flow generating projection 70 itself does not affect the heavy load tire 1. For this reason, 60 A of tread side parts can be cooled efficiently and the temperature rise of the tread part 50 can be suppressed more reliably.

  Here, since the diameter of the heavy load tire is larger than the diameter of the passenger vehicle tire, the distance from the tire rotation axis of the tread side portion 60A is longer than the distance from the tire rotation axis of the sidewall portion 60B. Thereby, the rotational speed of the tread side part 60A is faster than the rotational speed of the sidewall part 60B. For this reason, as described above, by providing the turbulent flow generation projection 70 on the tread side portion 60A, turbulent flow is easily generated in the tread side portion 60A, and the tread side portion 60A can be efficiently cooled. In particular, by providing the turbulent flow generation projection 70 at a position including the tread end 51 in the tread side portion 60A, the tread side portion 60A can be cooled more effectively.

  In the embodiment, the height h of the turbulent flow generation projection 70 is 3 to 10 mm. When the height h of the turbulent flow generation projection 70 is lower than 3 mm, the air flowing on the surface of the tread side portion 60A is hardly disturbed by the turbulent flow generation projection 70, and the tread side portion 60A cannot be efficiently cooled. There is. On the other hand, when the height h of the turbulent flow generation projection 70 is higher than 10 mm, the air over the turbulent flow generation projection 70 is difficult to hit the surface of the tread side portion 60A, and the tread side portion 60A cannot be efficiently cooled. There is.

  In the embodiment, the angle θ formed by at least one side surface 71 of the turbulent flow generation projection 70 and the surface of the tread side portion 60A is greater than 90 degrees, and is a cross section orthogonal to the extending direction of the turbulent flow generation projection 70. The shape is trapezoidal. That is, the lower side of the turbulent flow generation projection 70 is larger than the upper surface 72. According to this, the rigidity of the boundary (base portion) between the tread side portion 60A and the turbulent flow generation projection 70B is improved, and the durability of the turbulent flow generation projection 70 is improved.

  In the embodiment, the width w of the lower side of the turbulent flow generation projection 70 is 2 to 8 mm. If the width w of the lower side is smaller than 2 mm, the air flowing along the surface of the tread side portion 60A hits the turbulent flow generating projection 70, causing the turbulent flow generating projection 70 to vibrate and cracking at the base portion. (Cracking) may occur. On the other hand, when the width w of the lower side is larger than 8 mm, the heat storage amount of the turbulent flow generation projection 70 itself increases, and the tread side portion 60A may not be efficiently cooled.

  In the embodiment, 1.0 ≦ p / h ≦ 50.0 and 1.0 ≦ (p−w) /w≦100.0 are satisfied. Further, the relationship of 2.0 ≦ p / h ≦ 24.0 (10.0 ≦ p / h ≦ 20.0) and 4.0 ≦ (p−w) /w≦39.0 is satisfied. Further preferred.

  When the value of the ratio of the height h to the pitch p (p / h) is smaller than 1.0, the air that has overcome the turbulent flow generation projections 70 is the tread side portion 60A between the turbulent flow generation projections 70A. The tread side part 60A may not be efficiently cooled. On the other hand, if the value (p / h) of the ratio of the height h to the pitch p is greater than 20.0, the air flowing on the surface of the tread side portion 60A is less likely to be disturbed by the turbulent flow generation projection 70, and the tread side portion 60A. May not be cooled efficiently.

  When (p−w) / w is smaller than 1.0, the interval between the turbulent flow generation projections 70 adjacent in the tire circumferential direction TC becomes too narrow, and the tread side portion 60A between the turbulent flow generation projections 70A. It may be difficult to hit the surface. On the other hand, if (p−w) / w is larger than 100.0, the air flowing on the surface of the tread side portion 60A is hardly disturbed by the turbulent flow generation projection 70, and the tread side portion 60A may not be efficiently cooled. is there.

(5) Modification Example Next, a modification example of the heavy duty tire 1 according to the above-described embodiment will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected to the same part as the heavy load tire 1 which concerns on embodiment mentioned above, and a different part is mainly demonstrated.

(5-1) Modification 1
First, the configuration of the heavy duty tire A according to the first modification will be described with reference to the drawings. FIG. 5 is a perspective view showing a part of the heavy duty tire A according to the first modification.

  In the embodiment described above, the turbulent flow generation projection 70 extends along the tire radial direction. On the other hand, in the first modification, the turbulent flow generation projection 70A is inclined with respect to the straight line RL along the tire radial direction, as shown in FIG.

  Specifically, the inclination angle θ1 of the turbulent flow generation projection 70 with respect to the straight line RL is set in a range of −70 ° ≦ θ ≦ 70 °. Since the heavy load tire A is a rotating body, air flowing along the surface of the tire side portion 60 may be directed outward in the tire radial direction TR due to centrifugal force. For this reason, by setting the inclination angle θ1 in the range of −70 ° ≦ θ ≦ 70 °, the turbulent flow generation projection 70 can be arranged substantially orthogonal to the air flow, and the surface of the tread side portion 60A. The air that flows along is easily disturbed. Therefore, the tread side portion 60A can be cooled more efficiently.

(5-2) Modification 2
Next, the configuration of the turbulent flow generation projection 70B according to Modification 2 will be described with reference to the drawings. FIG. 6 is a perspective view showing a part of the turbulent flow generation projection 70B according to the second modification.

  In the above-described embodiment, the turbulent flow generation projection 70 continuously extends along the tire radial direction. On the other hand, in the modified example 2, as shown in FIG. 6, the turbulent flow generation projection 70B is provided with an intermittent portion along the tire radial direction.

  Specifically, through holes 75 are formed in the turbulent flow generation projection 70B at predetermined intervals in the tire radial direction. The through hole 75 penetrates along a direction orthogonal to the extending direction of the turbulent flow generation projection 70B (that is, the tire circumferential direction TC). As a result, the area of the boundary between the tread side portion 60A and the turbulent flow generation projection 70B (the lower side of the turbulent flow generation projection 70B) decreases, so that the shear strain generated at the boundary due to the deflection of the tread side portion 60A decreases. . Thereby, cracks are hardly generated at the boundary between the tread side portion 60A and the turbulent flow generation projection 70B, and the durability of the turbulent flow generation projection 70 is more reliably improved.

(6) Other Embodiments As described above, the contents of the present invention have been disclosed through the embodiments of the present invention. However, it is understood that the description and drawings constituting a part of this disclosure limit the present invention. Should not. From this disclosure, various alternative embodiments, examples, and operational techniques will be apparent to those skilled in the art.

  For example, the embodiment of the present invention can be modified as follows. Specifically, the tire has been described as being a heavy-duty tire 1 filled with air, nitrogen gas, or the like, but is not limited thereto, and may be a solid tire (no puncture tire). The heavy load tire 1 does not necessarily need to be a tire mounted on a large vehicle, and may be a tire mounted on a passenger car.

  In the embodiment, the configuration of the heavy load tire 1 is not limited to that described in the embodiment, and can be appropriately set according to the purpose.

  Further, the cross-sectional shape of the turbulent flow generation projection 70 has been described as a trapezoidal shape, but is not limited to this, for example, a regular square shape, a triangular shape, a stepped shape, a semicircular arc shape, and the like. It may be a simple shape. Specifically, the cross-sectional shape of the turbulent flow generation projection 70 may be the cross-sectional shape shown in FIGS. 7 to 9 are cross-sectional views in a direction orthogonal to the extending direction of the turbulent flow generation projection according to the other embodiment.

  7A and 7B, the cross-sectional shape of the turbulent flow generation projection 70 is a triangular shape. The angles formed between the side surface of the turbulent flow generation projection 70 and the surface of the tread side portion 60A are defined as an angle α and an angle β, respectively. As shown in FIG. 7A, the turbulent flow generation projection 70 may be provided so that the angle α and the angle β are larger than 90 degrees. As shown in FIG. 7B, the turbulent flow generation projection 70 is provided so that one angle (angle α) is 90 degrees and the other angle (angle β) is greater than 90 degrees. Also good. Further, the turbulent flow generation projection 70 may be provided so that the angle α is less than 90 degrees and the angle β is greater than 90 degrees.

  8A and 8B, the cross-sectional shape of the turbulent flow generation projection 70 is a stepped shape. As shown in FIG. 8A, the steps may be formed on both side surfaces of the turbulent flow generation projection 70. That is, in the cross section of the turbulent flow generation projection 70, the width between one side surface of the turbulent flow generation projection 70 and the other side surface of the turbulent flow generation projection 70 may be reduced stepwise. As shown in FIG. 8B, the step may be formed only on one side surface of the turbulent flow generation projection 70.

  The cross-sectional shape of the turbulent flow generation projection 70B according to Modification 2 is a trapezoidal shape. That is, the angle θ formed by at least one side surface of the turbulent flow generation projection 70B and the surface of the tread side portion 60A is greater than 90 degrees. As shown in FIG. 9A, the angle formed between the side surface of the turbulent flow generation projection 70B and the surface of the tread side portion 60A may be 90 degrees. Further, as shown in FIG. 9B, the cross-sectional shape of the turbulent flow generation projection 70B may be a stepped shape. That is, in the turbulent flow generation projection 70 shown in FIG. 8B, the shape is the same as the shape in which the through hole 75 is formed.

  Further, the turbulent flow generation projection 70 has been described as extending linearly along the tire radial direction, but is not limited to this, for example, zigzag or corrugated along the tire radial direction. It may extend and may be divided at predetermined intervals in the tire radial direction.

  As described above, the present invention naturally includes various embodiments that are not described herein. Therefore, the technical scope of the present invention is determined only by the invention specifying matters according to the scope of claims reasonable from the above description.

DESCRIPTION OF SYMBOLS 1,1A ... Heavy load tire, 10 ... Bead part, 11 ... Bead core, 13 ... Bead filler, 15 ... Bead inner end, 20 ... Carcass layer, 30 ... Inner liner, 40 ... Belt layer, 50 ... Tread part, 51 ... Tread grounding end, 53 ... outermost position of tread, 60 ... tire side portion, 60A ... tread side portion, 60B ... sidewall portion, 70, 70A, 70B ... turbulent flow generation projection, 71 ... side surface, 72 ... upper surface, 75 ... through hole

Claims (5)

A part of the tire side part from the tread end to the bead part located outside the tread width direction of the tread part in contact with the road surface protrudes outward from the tire side part in the tread width direction and extends along the tire radial direction. A tire provided with a plurality of existing turbulent flow generation projections,
The turbulent flow generation protrusion is provided only within a range from the tread end to a position radially inward of the tire cross-section height by a quarter of the tire cross-section height.
When the height of the turbulent flow generation projection is h, the width perpendicular to the extending direction of the turbulent flow generation projection is w, and the interval between the turbulent flow generation projections adjacent in the tire circumferential direction is d, d >H> w is satisfied,
A belt layer is provided on the inner side in the tire radial direction of the tread portion,
The tire radial direction outer end of the turbulent flow generation projection is provided on the tire radial direction outer side than the belt layer ,
A tire whose cross-sectional shape along the extending direction of the turbulent flow generation projection is a trapezoid whose inner side in the tread width direction is longer than the outer side in the tread width direction .   The tire according to claim 1, wherein a height h of the turbulent flow generation projection is 3 to 10 mm.   The cross section perpendicular to the extending direction of the turbulent flow generation protrusion, an angle formed by at least one side surface of the turbulent flow generation protrusion and the surface of the tire side portion is greater than 90 degrees. 2. The tire according to 2.   The tire according to claim 3, wherein a cross-sectional shape perpendicular to the extending direction of the turbulent flow generation projection is a trapezoidal shape.   The tire according to any one of claims 1 to 4, wherein an outer end portion of the turbulent flow generation protrusion in a tire radial direction is provided at a position equal to the tread end.

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