JP2013136332A - Tire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To have air turbulence generation protrusions which are resistant to peeling or cracking caused by outer damage and have resistance to swinging in wind.SOLUTION: An air turbulence generation protrusion 40 includes: a protrusion 60 provided in a tire side part 14; and a protection part 62 covering the protrusion 60 and having an elongation modulus at 100% lower than that of the protrusion 60.

Description

  The present invention relates to a tire.

  Conventionally, in tires mounted on automobiles, particularly heavy-duty tires mounted on construction vehicles such as dump trucks, in order to suppress the temperature rise of the side portions due to traveling of the construction vehicles, the tire radial direction on the tire side portions A structure in which a fin-like projection for generating a turbulent flow extending along the line is provided. In this structure, the air flowing along the tire side portion overcomes the turbulent flow generation protrusion, and the air whose flow is disturbed is attached to the tire side portion again, thereby promoting the heat radiation of the tire side portion.

International Publication No. 2010/126091 Pamphlet

  By the way, the turbulent flow generation projection as described above can be weak against baldness and chipping due to trauma when its 100% elongation modulus is high. On the other hand, if the 100% elongation modulus of the turbulent flow generation projection is low, the turbulent flow generation projection can not withstand the wind received during rolling of the tire and flutters, and the heat dissipation performance can be reduced.

  In view of the above circumstances, an object of the present invention is to provide a tire having a turbulent flow generation projection that is resistant to flaking and chipping due to trauma and is difficult to flutter.

A tire according to a first aspect of the present invention is a turbulent flow generation projection comprising: a projection provided on a tire side portion; and a protection portion that covers the projection and has a 100% elongation modulus lower than that of the projection. , Having a tire.
The “covering the protruding portion” means covering all or a part of the protruding portion.

According to this configuration, since the surface of the turbulent flow generation projection is a protective portion having a modulus of expansion 100% lower than that of the projection, the turbulent flow generation projection is strong against baldness and chipping due to trauma.
Further, the protrusion has a 100% higher elongation modulus than the protection part, and the protrusion for turbulent flow generation as a composite structure is less likely to fly against the wind received when the tire rolls.

  In the tire according to the second aspect of the present invention, in the first aspect, the volume of the protrusion is larger than the volume of the protection part.

  According to this configuration, since the protrusion having a 100% elongation modulus higher than that of the protective part occupies more than half of the volume of the turbulent flow generation protrusion, the turbulent flow generation protrusion is affected by the wind received when the tire rolls. On the other hand, it becomes more difficult to fly.

  In the tire according to the third aspect of the present invention, in the first aspect or the second aspect, the protection portion covers the entire side surface of the protrusion.

  According to this configuration, the width of the turbulent flow generation projection can be increased compared to the configuration in which only the top surface of the projection portion is covered, and therefore, it becomes more difficult to fly against the wind received during tire rolling. Further, since the boundary between the protective portion and the protruding portion is eliminated with respect to the wind received during tire rolling, the protective portion and the protruding portion are difficult to separate.

  In the tire according to the fourth aspect of the present invention, in any one of the first aspect to the third aspect, the protection part covers the entire protrusion.

  According to this configuration, it is only necessary to attach a single rubber sheet or the like as a protective portion to the tire side portion, and thus it is easy to form the protective portion.

  In the tire according to the fifth aspect of the present invention, in any one of the first to fourth aspects, the turbulent flow generation projection has a rectangular cross section.

  According to this configuration, the resistance to wind received during rolling of the tire can be increased as compared with the case where the cross-sectional shape of the turbulent flow generation projection is a triangular shape, etc. The heat radiation effect of the side portion can be enhanced.

  In the tire according to the sixth aspect of the present invention, in any one of the first to fifth aspects, the tip of the protrusion has a curved shape.

  According to this configuration, since the protrusion has no corner, it is difficult to chip, and the protection part and the protrusion are difficult to separate.

  In the tire according to the seventh aspect of the present invention, in any one of the first aspect to the fifth aspect, the top portion of the protruding portion has a step shape.

  According to this configuration, the contact area between the protection part and the protrusion part is increased, so that the protection part and the protrusion part are difficult to separate.

  In the tire according to the eighth aspect of the present invention, in any one of the first to seventh aspects, the difference between the 100% elongation modulus of the protrusion and the 100% elongation modulus of the protection portion is 0. It is 5 MPa or more and 20 MPa or less.

  According to this structure, it can suppress that a projection part is missing with a protection part, or a projection part is swung by a protection part. Moreover, generation | occurrence | production of a baldness, distortion, a crack, etc. can be suppressed also in the interface surface of a protection part and a projection part.

  A tire according to a ninth aspect of the present invention is the tire according to any one of the first to eighth aspects, wherein a 100% expansion modulus is between the protrusion and the protection part. An intermediate layer having an intermediate value is provided.

  According to this configuration, even if there is an extreme 100% elongation modulus difference between the protrusion and the protection part, the intermediate layer is provided between the protrusion and the protection part, so that the protrusion and the intermediate layer are protected. 100% expansion modulus difference can be reduced between the intermediate part and the intermediate layer, and it is possible to suppress the occurrence of strain, cracks, baldness, etc. at the interface between the projection part and the intermediate layer and between the protective part and the intermediate layer. it can.

  Since the present invention has the above-described configuration, it is possible to provide a tire having a turbulent flow generation projection that is resistant to baldness and chipping and is difficult to flutter.

FIG. 1 is a side view of a tire 10 according to a first embodiment of the present invention. FIG. 2 is a partially exploded perspective view of the tire 10 according to the embodiment of the present invention. FIG. 3 is a cross-sectional view of the tire 10 according to the embodiment of the present invention. FIG. 4 is a partially exploded perspective view of the turbulent flow generation projection 40 of the tire 10 according to the embodiment of the present invention. FIG. 5 is an explanatory diagram of turbulent flow generation by the turbulent flow generation projection 40. FIG. 6 is a partially exploded perspective view of the turbulent flow generation projection 100 of the tire according to the second embodiment of the present invention. FIG. 7 is a partially exploded perspective view of the tire turbulent flow generation projection 200 according to the third embodiment of the present invention. FIG. 8 is a side view of a tire according to a modification. FIG. 9 is a cross-sectional view of a turbulent flow generation projection according to a modification. FIG. 10 is a cross-sectional view of a turbulent flow generation projection according to another modification.

  Hereinafter, a tire according to an embodiment of the present invention will be specifically described with reference to the accompanying drawings. In the drawings, members (components) having the same or corresponding functions are denoted by the same reference numerals and description thereof is omitted as appropriate. In addition, the terms “upper” and “lower” used in the following description are used for convenience and should not be constrained in a direction.

<First Embodiment>
The tire according to the first embodiment is a heavy duty pneumatic tire mounted on a construction vehicle such as a dump truck.

-Overall configuration-
FIG. 1 is a side view of a tire 10 according to a first embodiment of the present invention.

  As shown in FIG. 1, the tire 10 is divided into a tread portion 12 that contacts the road surface during traveling and tire side portions 14 on both sides of the tire 10 in the tire rotation axis direction. Further, the tire side portion 14 is divided into a bead portion 16, a shoulder portion 18, and a tire side portion 20 located between the bead portion 16 and the shoulder portion 18 along the tire radial direction.

  FIG. 2 is a partially exploded perspective view of the tire 10 according to the embodiment of the present invention.

  As shown in FIG. 2, the tire 10 includes a carcass 30 that forms a skeleton of the tire 10, a bead 32 that is disposed on a bead portion 16 and that fits a rim flange (not shown), which will be described later, and a carcass. 30 and a belt layer 34 disposed in the tread portion 12 on the outer side in the tire radial direction.

The carcass 30 includes a carcass cord and a layer made of rubber that covers the carcass cord. The beads 32 are disposed along the tire circumferential direction C, and are provided on both sides in the tread width direction W (tire rotation axis direction) via the tire equator line CL, and have a bead core 32A and a bead filler 32B. . Specifically, a steel cord or the like is used as the bead core 32A.
The belt layer 34 is configured by impregnating an organic fiber cord with a rubber component. The belt layer 34 includes a plurality of layers, and each layer is arranged along the tire radial direction D.

  In the present embodiment, turbulent flow generation projections 40 are provided at regular intervals around the entire circumference of the tire side portion 20 of the tire side portion 14 and extend along the tire radial direction D. The turbulent flow generation protrusion 40 includes a first protrusion 42 and a second protrusion 44 and a third protrusion 46 that are separate from the first protrusion 42.

  The second protrusion 44 is provided at a position different from the first protrusion 42 in the tire circumferential direction. The third protrusion 46 is provided at the same position as the first protrusion 42 in the tire circumferential direction. Specifically, the second protrusion 44 is adjacent to the first protrusion 42 and the third protrusion 46 in the tire circumferential direction, and a predetermined gap is formed between the first protrusion 42 and the second protrusion 44. Yes. Similarly, a predetermined gap is formed between the third protrusion 46 and the second protrusion 44. Thus, since the second protrusion 44 is provided at a position different from the first protrusion 42 and the third protrusion 46 in the tire circumferential direction C, the oil component adheres to the turbulent flow generation protrusion 40 and the tire radial direction D Even when it is deformed, the contact between the second protrusion 44 and the first protrusion 42 or the third protrusion 46 can be suppressed, so that further deformation of each protrusion 42, 44, 46 can be suppressed.

  FIG. 3 is a cross-sectional view of the tire 10 according to the embodiment of the present invention.

  As shown in FIG. 3, in the state where the tire 10 is assembled to the rim wheel 50, the distance d from the upper end 52 </ b> A of the rim flange 52 of the rim wheel 50 to the lower end 40 </ b> A of the turbulent flow generation projection 40 is From the standpoint that the turbulent flow generation projection 40 does not get in the way during assembly, it is 50 mm or more. The state where the tire 10 is assembled to the rim wheel 50 means a state where the tire 10 is assembled to a standard rim described in ETRTO with air pressure corresponding to the maximum load described in ETRTO. Further, the upper end 52A of the rim flange 52 indicates the end of the rim flange 52 outside the tire radial direction D. The lower end 40 </ b> A of the turbulent flow generation projection 40 indicates an end portion on the inner side in the tire radial direction D of the third projection 46 constituting the turbulent flow generation projection 40.

-Configuration of the turbulent flow generation projection 40-
FIG. 4 is a partially exploded perspective view of the turbulent flow generation projection 40 of the tire 10 according to the embodiment of the present invention.

  As shown in FIG. 4, each protrusion 42, 44, 46 of the turbulent flow generation protrusion 40 has a width w along the tire circumferential direction C, a length L along the tire radial direction D, and a height h. The width w is preferably 2 mm or more and 10 mm or less, for example. The length L is preferably set to, for example, 10 mm or more and 500 mm or less. The height h is preferably 3 mm or more and 25 mm or less, for example.

  The inner end in the tire radial direction D of the first protrusion 42 in the turbulent flow generation protrusion 40 overlaps the outer end in the tire radial direction D of the second protrusion 44 in the tire radial direction D. Similarly, the outer end portion of the third protrusion 46 in the tire radial direction D overlaps the inner end portion of the second protrusion 44 in the tire radial direction D in the tire radial direction D.

  These projections 42, 44, 46 are constituted by a projection portion 60 and a protection portion 62. The following description of the protrusion 60 and the protection part 62 is common to the protrusions 42, 44, 46.

  The protruding portion 60 protrudes from the tire side portion 20 in the tread width direction W, and the tip thereof has a curved surface shape. The material of the projecting portion 60 is an elastic body including rubber.

The protection part 62 covers the entire surface of the protrusion 60, and has a 100% extension modulus lower than that of the protrusion 60. As a result, the entire surface of the turbulent flow generation projection 40 becomes the protective portion 62 having a modulus of elongation that is 100% lower than that of the projection portion, so that the turbulent flow generation projection 40 is resistant to baldness and chipping due to trauma. Further, the protrusion 60 serving as the core of the turbulent flow generation protrusion 40 has a 100% higher modulus of elasticity than the protection part 62, and the turbulent flow generation protrusion 40 as a composite structure receives wind during tire rolling. It becomes difficult to flutter against.
Further, it is possible to sufficiently prevent a difference in the 100% expansion modulus between the protective part 62 and the protruding part 60 to prevent the protruding part 60 from being chipped together with the protective part 62 or from being swung by the protective part 62. From the viewpoint, it is preferable that the 100% elongation modulus of the protection portion 62 is lower than the 100% elongation modulus of the protrusion 60 by 0.5 MPa or more. Further, from the viewpoint of reducing the 100% expansion modulus difference (rigidity step) and suppressing the occurrence of baldness, distortion, cracks, etc. at the boundary surface between the protective portion 62 and the protrusion 60, the protective portion 62 is stretched 100%. The modulus is preferably lower by 20 MPa or less than the 100% elongation modulus of the protrusion 60. Further, the 100% elongation modulus of the protective portion 62 and the protrusion 60 is such that the rubber (the material of the protrusion 60) enters during vulcanization so that the protrusion 60 can be easily formed, and the difference in 100% elongation modulus. From the viewpoint that the (rigidity step) can be reduced, it is preferably lower than the 100% elongation modulus of the rubber material 10A (may be referred to as the tire body 10A) constituting the tire 10, for example, 1 MPa or more and 2 MPa or less. It is particularly preferred that it be lowered.
The height of the 100% elongation modulus of the protrusion 60 and the protection portion 62 and the height of the 100% elongation modulus of the rubber material 10A are the same materials as those constituting the protrusion 60, the protection portion 62, or the rubber material 10A, respectively. It can be confirmed by preparing a JIS No. 3 test piece using, performing a tensile test according to JIS K6251 and measuring the tensile stress (M100) at 100% elongation.
The 100% elongation modulus can be adjusted by selecting the material and composition of the protrusions 60 and the protection part 62, selecting the type and blending of the vulcanizing agent, and adding impurities. For example, as the vulcanizing agent, all those conventionally used in general rubber compositions can be used, for example, dicumyl peroxide, benzoyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5. -Di (t-butylperoxy) -hexane, 2,5-dimethyl-2,5-di (t-butylperoxy) -hexyne-3 and the like.

  The value of the 100% elongation modulus itself of the protrusion 60 and the protection part 62 is not particularly limited. For example, the 100% elongation modulus of the protrusion 60 is 0.8 MPa or more and 3.5 MPa or less. The% elongation modulus is preferably set to, for example, 0.3 MPa or more and 3.0 MPa or less.

  Further, the outer shape of the protection portion 62 is rectangular (that is, the shape of the turbulent flow generation projection 40 is rectangular). The formation method of the protection part 62 is not particularly limited. In the first embodiment, the rubber sheet 70 is attached to the entire circumference of the tire 10 from the viewpoint of easy formation of the protection part 62, and the protection part 62 has a rectangular shape. It is formed by scraping a part of the rubber sheet as appropriate.

Further, the volume of the protrusion 60 is made larger than the volume of the protection part 62 (in the first embodiment, it is not the entire volume of the rubber sheet 70 but only the component part of the turbulent flow generation protrusion 40). Yes. As a result, the protrusion 60 having a 100% elongation modulus higher than that of the protection part 62 occupies more than half of the volume of the turbulent flow generation protrusion 40, and the turbulent flow generation protrusion 40 receives wind during tire rolling. On the other hand, it becomes more difficult to fly.
In relation to this, from the maximum height of the protrusion 60 (the vertex of the curved surface shape in the first embodiment) to the maximum height of the protection portion 62 (the surface on the side of the rectangular tread width direction W in the first embodiment). The length P2 along the tread width direction W is the length along the tread width direction W from the surface of the tire side portion 20 (the boundary surface between the protrusion 60 and the rubber material 10A) to the maximum height of the protection portion 62. It is preferable that it is 1/4 or less with respect to P1. Since the protrusion 60 having a 100% elongation modulus higher than that of the protection part 62 occupies more than 3/4 of the height of the turbulent flow generation protrusion 40, the turbulent flow generation protrusion 40 as a whole flutters more with respect to the wind. It becomes difficult.
Further, the tread width direction from the maximum height of the protrusion 60 (the vertex of the curved surface shape in the first embodiment) to the maximum height of the protection portion 62 (the surface on the W side in the rectangular tread width direction in the first embodiment). The length along W is 4 / with respect to the length along the tread width direction W from the surface of the tire side portion 20 (the boundary surface between the protrusion 60 and the rubber material 10A) to the maximum height of the protection portion 62. It is preferably 20 or less, and more preferably 3/20 or less.

-Effect-
FIG. 5 is an explanatory diagram of turbulent flow generation by the turbulent flow generation projection 40.

  As the tire 10 rotates, the air flow S1 that has been in contact with the tire side portion 20 where the turbulent flow generation projections 40 are not formed is separated from the tire side portion 20 by the turbulent flow generation projections 40 to generate turbulence. Get over the protrusion 40. At this time, a portion (region) S <b> 2 in which the air flow stays is generated on the back side of the turbulent flow generation projection 40. Then, the air flow S <b> 1 whose flow is disturbed by the turbulent flow generation projection 40 is reattached to the bottom portion between the next turbulent flow generation projection 40 and promotes heat radiation of the tire side portion 20. The turbulent flow generation projection 40 peels off again. At this time, a portion (region) S3 in which the air flow stays is generated between the air flow S1 and the separation at the next turbulent flow generation projection 40 again.

A series of air flows S1 generated by the turbulent flow generation projection 40 as described above is a turbulent flow. Note that it is considered that increasing the velocity gradient (velocity) on the region in contact with the turbulent flow S1 is advantageous for increasing the heat dissipation rate.
In the first embodiment, the turbulent flow generation projection is provided on the tire side portion 20 where deterioration is likely to occur compared to other portions, so that the turbulent flow S1 of the air generated by the turbulent flow generation projection 40 is achieved. Therefore, the heat radiation of the tire side portion 20 can be promoted. This is because the rubber material 10 constituting the tire 10 is a material with poor thermal conductivity, so that the generation of the turbulent flow S1 is promoted and the turbulent air flow S1 is generated rather than enlarging the heat radiation area and promoting the heat radiation. It is considered that the heat dissipation effect is increased by direct contact with the tire side portion 20.
In particular, the tire side portion 20 in comparison with other portions in long-term use, such as a heavy load tire, a run flat tire having a tire side portion 20 provided with a crescent-shaped reinforcing rubber, and a TBR (track bus radial) In a pneumatic tire having a portion where failure is likely to occur, the effect of reducing the temperature of the tire side portion 20 is enhanced.

In the first embodiment, the turbulent flow generation projection 40 includes a first projection 42, a second projection 44, and a third projection 46, and an inner end portion of the first projection 42 in the tire radial direction D. Overlaps with the outer end of the second protrusion 44 in the tire radial direction D in the tire radial direction D. For this reason, the flow of the air flowing along the tire side portion 20 is disturbed by getting over the first protrusion 42 or the second protrusion 44. The air in which the flow is disturbed adheres to the tire side portion 20 again, whereby the heat dissipation effect of the tire side portion 20 can be obtained.
The second protrusion 44 is adjacent to the first protrusion 42 in the tire circumferential direction C, and a predetermined gap is formed between the first protrusion and the second protrusion 44. The flowing air is more likely to get over the first protrusion 42 or the second protrusion 44. That is, the heat dissipation effect of the tire side portion 20 by getting over the first protrusion 42 or the second protrusion 44 can be further improved. In addition, since a predetermined gap is formed between the first protrusion 42 and the second protrusion 44, the first protrusion 42 even when the first protrusion 42 and the second protrusion 44 are deformed in the tire radial direction D. And the second protrusion 44 can be prevented from contacting each other.
Since the relationship between the third protrusion and the second protrusion is the same as the relationship between the first protrusion and the third protrusion, the same effect as described above can be obtained.

  Here, in the conventional turbulent flow generation projection, if its 100% elongation modulus is high, it may be vulnerable to baldness and chipping due to trauma. On the other hand, if the 100% expansion modulus of the turbulent flow generation projection is low, the turbulent flow generation projections cannot withstand the wind received during tire rolling (during rotation), and the heat dissipation performance may be reduced.

  Therefore, the turbulent flow generation projection 40 (the first projection 42, the second projection 44, and the third projection 46) of the tire 10 according to the first embodiment includes the projection 60 provided on the tire side portion 20, and the projection The protective part 62 covers the entire 60 and has a modulus of expansion 100% lower than that of the protruding part 60.

  As a result, the entire surface in contact with the outside of the turbulent flow generation projection 40 becomes the protection portion 62 having a 100% lower expansion modulus than the projection portion 60, so that the turbulent flow generation projection 40 is resistant to flaking and chipping due to trauma. Further, the protrusion 60 constituting the core of the turbulent flow generation protrusion 40 has a 100% higher expansion modulus than the protection part 62, and the turbulent flow generation protrusion 40 receives wind during tire rolling. It becomes difficult to fly against.

  Further, in the first embodiment, since the protection part 62 covers the entire side surface of the protrusion 60, turbulence is generated compared to the case where the protection part 62 is not provided or only the top surface of the protrusion 60 is covered. The width of the projection 40 can be increased, and it becomes more difficult to fly against the wind received when the tire rolls. In addition, since the boundary between the protection part 62 and the protrusion part 60 is eliminated with respect to the wind received during tire rolling (wind in the tire circumferential direction C), the protection part 62 and the protrusion part 60 are difficult to separate.

  Further, since the turbulent flow generation projection 40 has a rectangular shape, it is possible to increase the resistance to wind received when the tire rolls compared to a triangular shape or the like, thereby generating a strong turbulent flow S1 in the tire side portion 20. Thus, the heat dissipation effect of the tire side portion 20 can be enhanced.

  In addition, since the shape of the tip of the protrusion 60 is a curved surface, the protrusion 60 has no corners and is difficult to chip, and the protection part 62 and the protrusion 60 are difficult to separate.

Second Embodiment
Next, a tire according to a second embodiment of the present invention will be described.

-Configuration of the turbulent flow generation projection 100-
FIG. 6 is a partially exploded perspective view of the turbulent flow generation projection 100 of the tire according to the second embodiment of the present invention.

  Similar to the turbulent flow generation projection 40 of the first embodiment, the tire turbulent flow generation projection 100 according to the second embodiment of the present invention is arranged on the entire circumference of the tire side portion 20 at regular intervals. It extends along the radial direction D. The turbulent flow generation protrusion 100 includes a first protrusion 102, a second protrusion 104, and a third protrusion 106.

  These protrusions 102, 104, 106 are composed of a protrusion 108 and a protection part 110. The following description of the protrusions 108 and the protection part 110 is common to the protrusions 102, 104, and 106.

  The protruding portion 108 protrudes from the tire side portion 20 in the tread width direction W, and has a rectangular cross-sectional shape along the tread width direction W (tire rotation axis direction). Similarly, the outer shape of the protection part 110 is also rectangular (that is, the shape of the turbulent flow generation projection 100 is rectangular).

Unlike the first embodiment, the protection unit 110 covers only the top surface (surface in the tread width direction W) of the projection 108, and has a 100% extension modulus lower than that of the projection 108.
In addition, it is preferable to make it the same as that of 1st Embodiment about the 100% expansion | extension modulus of a protection part 110 and the projection part 108, a difference, a value, etc. of a volume. Further, from the maximum height of the protrusion 108 (the surface on the W side in the rectangular tread width direction in the second embodiment) to the maximum height of the protection unit 110 (the surface on the W side in the rectangular tread width direction in the second embodiment). ) Along the tread width direction W up to the maximum height of the protection portion 110 from the surface of the tire side portion 20 (the boundary surface between the protrusion 108 and the rubber material 10A). It is preferable to be 1/4 or less with respect to the length P3.

-Effect-
According to the configuration of the second embodiment of the present invention, the top surface (surface in the tread width direction W) in contact with the outside of the turbulent flow generation projection 100 becomes the protection portion 110 having a 100% extension modulus lower than that of the projection portion 108. Therefore, the turbulent flow generation projection 100 is resistant to baldness and chipping due to trauma. In addition, the protrusion 108 constituting the core of the turbulent flow generation protrusion 100 has a 100% higher modulus of elasticity than the protection part 110, and the turbulent flow generation protrusion 100 receives wind during tire rolling. It becomes difficult to fly against.
In the second embodiment, in particular, since the cross-sectional shape of the protrusion 108 is rectangular, it has a corner, but the corner on the Tread width direction W side is covered with the protective portion 110, and therefore, due to trauma. The baldness and chipping at the corners of the protrusion 108 are suppressed.

  Moreover, since the protection part 110 covers only the top surface of the projection part 108, material cost can be suppressed.

<Third Embodiment>
Next, a tire according to a third embodiment of the present invention will be described.

-Configuration of the turbulent flow generation projection 100-
FIG. 7 is a partially exploded perspective view of the tire turbulent flow generation projection 200 according to the third embodiment of the present invention.

  Similar to the turbulent flow generation projection 40 of the first embodiment, the tire turbulent flow generation projections 200 according to the third embodiment of the present invention are arranged at regular intervals on the entire circumference of the tire side portion 20. It extends along the radial direction D. The turbulent flow generation projection 200 includes a first projection 202, a second projection 204, and a third projection 206.

  These protrusions 202, 204, and 206 include a protrusion 208 and a protection part 210. The following description of the protrusions 208 and the protection part 210 is common to the protrusions 202, 204, and 206.

  The protrusion 208 protrudes from the tire side portion 20 in the tread width direction W, and has a rectangular cross-sectional shape along the tread width direction W (tire rotation axis). Similarly, the shape of the protection part 210 including the protrusion 208 is also rectangular.

Unlike the first embodiment, the protection part 210 covers only the entire side surfaces (both sides in the tire circumferential direction C and both sides in the tire radial direction D) of the protrusion 208, and has a 100% extension modulus lower than that of the protrusion 208. Has been.
In addition, it is preferable that the height difference and the value of the 100% expansion modulus between the protection part 210 and the projection part 208 are the same as those in the first embodiment.

-Effect-
According to the configuration of the third embodiment of the present invention, the side surfaces (both surfaces in the tire circumferential direction C and both surfaces in the tire radial direction D) that are in contact with the outside of the turbulent flow generation projection 200 have a 100% expansion modulus than the projection portion 208. Since the protection portion 210 is low, the turbulent flow generation projection 200 is resistant to baldness and chipping due to trauma. Further, the protrusion 208 that forms the core of the turbulent flow generation protrusion 200 has a 100% higher modulus of elasticity than the protection part 210, and the wind that the turbulent flow generation protrusion 200 receives when the tire rolls. It becomes difficult to fly against.
In the third embodiment, in particular, since the cross-sectional shape of the protrusion 208 is rectangular, it has corners. However, the corner on the side surface side is covered with the protection part 210, and thus the protrusion 208 due to trauma. The baldness and chipping of the corners of the are suppressed.

Moreover, since the protection part 210 covers only the whole side surface of the projection part 208, material cost can be suppressed.
Furthermore, since the protection part 210 covers the entire side surface of the projection part 208, the width of the turbulent flow generation projection 200 can be reduced as compared with the case where the protection part 208 is not provided or only the top surface of the projection part 210 is covered. It can be widened, and it becomes more difficult to fly against the wind received when the tire rolls. In addition, since the boundary between the protection portion 210 and the projection portion 208 is eliminated with respect to the wind (wind in the tire circumferential direction C) received during tire rolling, the protection portion 210 and the projection portion 208 are difficult to separate.

<Modification>
Although the present invention has been described in detail with respect to specific embodiments, the present invention is not limited to such embodiments, and various other embodiments are possible within the scope of the present invention. It will be apparent to those skilled in the art, and for example, the plurality of embodiments described above can be implemented in combination as appropriate. Further, the following modifications may be combined as appropriate.

  For example, in the first to third embodiments, the case where the turbulent flow generation projections 40, 100, and 200 are provided on the tire side portion 20 has been described. Part 18) may be provided. However, from the viewpoint of preventing the turbulent flow generation protrusions 40, 100, and 200 from interfering when the rim wheel 50 is assembled, the turbulent flow generation protrusions 40, 100, and 200 are beaded in the tire side portion 14. It is preferable to provide the tire side portion 20 or the shoulder portion 18 other than the portion 16. Further, the turbulent flow generation projections 40, 100, 200 may be provided on both the bead portion 16 and the shoulder portion 18, the bead portion 16 and the tire side portion 20, the tire side portion 20 and the shoulder portion 18, etc. You may make it provide in the bead part 16, the shoulder part 18, and the tire side part 20 altogether.

In the first to third embodiments, the turbulent flow generation projections 40, 100, and 200 are each configured with a plurality of projections. However, as shown in FIG. The turbulent flow generation projections 300 that are arranged so as to extend substantially in the same direction as the tire radial direction and are formed as ridges may be provided intermittently along the tire circumferential direction. The number and arrangement are not particularly limited.
Here, the configuration of the protrusions of the turbulent flow generation protrusion 300 is not limited to a common configuration, and may not be the same. For example, you may combine the case where a projection part is covered with a protection part, and the case where it is not covered for every protrusion of the protrusion 300 for turbulent flow generation. Specifically, in FIG. 8, eight turbulent flow generation projections 300 are arranged at narrow intervals along the tire circumferential direction, and five such arrangements are made wider than the above-mentioned interval and the tire Although it is provided in the side part 20, about the protrusion of the forefront line (1st or 8th counting from the tire circumferential direction C) among the eight turbulent flow generation protrusions 300 in each set, the protrusion part and the protection part The other protrusions may be configured only by the protrusions. Of the eight turbulent flow generation projections 300 in each group, the front row is easily subjected to the strongest wind and is likely to be chipped. Therefore, it is considered suitable for carrying out the present invention.

  Similarly, the configuration of the protrusions 42, 44, and 46 has been described as being common, but only a part of the protrusions 42, 44, and 46 may be configured as in the embodiment. Only the configuration of the first embodiment may be used, and the second projections 44 and 46 may be replaced with the configuration of the second embodiment (the second projection 104 and the third projection 106). Of the protrusions 42, 44, 46, the protrusion on the side that receives the turbulent flow S1 first (the protrusion on the near side in the tire rotation direction G, the first protrusion 42 and the third protrusion 46, or the second protrusion). 44) may be composed of a protrusion and a protection part.

  In the first embodiment, the case where the protection unit 62 covers the entire surface of the projection 60 will be described. In the second and third embodiments, the protection units 110 and 210 are part of the projections 108 and 208. Although the case where (the entire top surface and side surface) is covered has been described, the protection unit may cover only a part of the top surface and side surfaces such as only the corners of the protrusions.

  Moreover, although the case where the front-end | tip of the projection part 60 was made into the curved surface shape was demonstrated, the cross-sectional shape of the projection part 60 may be triangular shape, square shape, pentagon shape etc., for example. Further, as shown in FIG. 9A, the entire surface may be covered with a protective portion 402, and the top portion may be a stepped protrusion 400. In this way, the contact area between the protection part 402 and the projection part 400 increases and it becomes difficult to separate them from each other.

  Further, as shown in FIG. 9B, in the tread width direction W, an intermediate layer in which the 100% expansion modulus is set to an intermediate value between the protruding portion 500 and the protecting portion 502 between the protruding portion 500 and the protecting portion 502. 504 may be provided.

  Further, the case where the turbulent flow generation projection 40 includes one projection portion 60 has been described, but as illustrated in FIG. 9C, a plurality of projection portions 600 covered with a protection portion 602 are provided. Also good. This makes it more difficult for the turbulent flow generation projection to fly against the wind received when the tire rolls.

Further, as shown in FIG. 10A, a part of the side surface and the top surface of the protrusion 700 may be covered with a curved protective portion 702. Here, a part of the side surface of the protrusion 700 will be described in detail. In FIG. 10 (A), the side surface (the front surface in the tire rotation direction G) that receives the turbulent flow S <b> 1 is covered with the protective portion 702 among some of the side surfaces of the protrusion 700. By doing in this way, the surface of the turbulent flow generation projection on the side that directly receives the turbulent flow S1 becomes the protection portion 702, so that the turbulent flow generation projection is prevented from debris flying with the turbulent flow S1. It becomes difficult to chip. That is, it can be said that it is effective to cover the side surface receiving the turbulent flow S <b> 1 with the protective portion 702 among the side surfaces.
From the same point of view, as shown in FIG. 10B, the entire protrusion 800 may be covered with a protective portion 802 having a different thickness in the tire circumferential direction C. Specifically, the thickness of the protective portion 802 on the side that receives the turbulent flow S1 (the front side in the tire rotation direction G) is thicker than the thickness of the protective portion 802 that faces the side that receives the turbulent flow S1. By doing so, the surface of the turbulent flow generation projection on the side that directly receives the turbulent flow S1 is covered with a thick protective portion, so that the turbulent flow generation projection against the dust flying along with the turbulent flow S1 In addition, since the thickness of the thick protective portion and the protective portion facing each other through the protrusion 800 is thin, the material cost can be suppressed.

  In addition, the case where the protection part 62 is attached to the protrusion 60 has been described. However, the protection part 62 is set in advance on the mold portion to be the protrusion, and the protection part 62 is formed at the same time as the protrusion is formed. You can also.

  Further, although the case where the tire 10 is a pneumatic tire has been described, the pneumatic tire is a tire filled with air at a predetermined pressure, but is filled with an inert gas such as nitrogen gas instead of air. Also good. Moreover, an airless tire may be sufficient.

  Moreover, although the case where rubber | gum was each included as a raw material of the projection part 60 and the protection part 62 was demonstrated, the material of the projection part 60 and the protection part 62, especially the material of the protection part 62 is not specifically limited, Resin etc. are used. be able to.

<Example>
Examples will be described below, but the present invention is not limited to these examples.

  A plurality of heavy-duty tires were prepared in which a turbulent flow generation protrusion having a difference in 100% elongation modulus between the protrusion and the protective portion of 0 MPa to 25 MPa was provided on the tire side portion. When the difference in 100% elongation modulus exceeds 0 MPa, the 100% elongation modulus of the protective portion is set lower than the 100% elongation modulus of the protrusion.

These tires were mounted on a vehicle and rotated until the turbulent flow generation protrusions of the tire provided with the turbulent flow generation protrusions having a 100% elongation modulus difference of 0 MPa fluttered. At this time, chipping and fluttering of each turbulent flow generation protrusion, baldness and distortion at the interface, and cracks were confirmed.
Table 1 shows the results of confirming the properties (chips, fluttering, etc.) of each turbulent flow generation protrusion in which the difference in 100% elongation modulus between the protrusion and the protective part is 0 MPa or more and 25 MPa or less. “X” in the table means that all fluttering and chipping occur, or baldness, distortion, and cracking all occur on the boundary surface, and “○” indicates that all fluttering and chipping do not occur or on the boundary surface. This means that no baldness, distortion, or cracks will occur, and “△” means that there is no flickering and chipping, or there is baldness at the interface and there is no cracking. means.

  As shown in Table 1, when there was no 100% elongation modulus difference between the protrusion and the protective part, both chipping and fluttering occurred. Further, when the difference in modulus of 100% elongation between the protrusion and the protective part was more than 0 MPa and less than 0.5 MPa, only chipping occurred. Further, when the 100% elongation modulus difference between the protrusion and the protective part exceeded 20 MPa, distortion and cracks occurred at the interface between the protrusion and the protective part.

  From the above, it is necessary to make the 100% extension modulus of the protective part lower than the 100% extension modulus of the protrusion part in order to make the turbulent flow generation protrusion resistant to flaking and chipping due to injury and difficult to fly. Furthermore, it was confirmed that it is preferable that the 100% elongation modulus of the protective part be lower by 0.5 MPa or more and 20 MPa or less than the 100% elongation modulus of the protruding part from the viewpoint of strengthening due to baldness or chipping.

10 Tire 14 Tire side portion 40, 100, 200 Turbulence generating protrusion (protrusion)
42, 102, 202 First protrusion (protrusion)
44, 104, 204 Second protrusion (protrusion)
46, 106, 206 Third protrusion (protrusion)
60, 108, 208, 400, 500, 600, 700, 800 Protruding part 62, 110, 210, 402, 502, 602, 702, 802 Protective part 504 Intermediate layer

Claims (9)

A turbulent flow generation projection, comprising: a projection provided on a tire side portion; and a protection portion that covers the projection and has a lower modulus of expansion by 100% than the projection,
Tire with. The volume of the protrusion is larger than the volume of the protective part.
The tire according to claim 1. The protection part covers the entire side surface of the protrusion,
The tire according to claim 1 or claim 2. The protective part covers the whole of the protruding part,
The tire according to any one of claims 1 to 3. The cross section of the turbulent flow generation projection is rectangular.
The tire according to any one of claims 1 to 4. The tip of the protrusion has a curved shape,
The tire according to any one of claims 1 to 5. The top of the protrusion has a staircase shape,
The tire according to any one of claims 2 to 5. The difference between the 100% elongation modulus of the protrusion and the 100% elongation modulus of the protective part is 0.5 MPa or more and 20 MPa or less.
The tire according to any one of claims 1 to 7. An intermediate layer having a 100% elongation modulus between the protrusion and the protection part is set to an intermediate value between the protrusion and the protection part.
The tire according to any one of claims 1 to 8.

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