JP7472466B2 - tire - Google Patents

Description

The present invention relates to a tire with a belt layer disposed inside the tread portion.

Conventionally, various tires that have a belt layer disposed inside the tread portion and are suitable for high-speed driving used in automobile racing and the like are known. For example, the following Patent Document 1 proposes a pneumatic tire that achieves both steering stability and durability by adopting a folded ply structure in which the axial end of the belt layer is folded back and by having a tread portion with a specific profile.

Publication No. 2015-101256

However, tires with a folded ply structure have lower steering stability than tires with a cut ply structure in which the axial ends of the belt layers are not folded back, and further improvements are needed to achieve both steering stability and durability.

The present invention was devised in consideration of the above-mentioned circumstances, and its main objective is to provide a tire that can achieve a good balance between steering stability and durability.

The present invention is a tire having a tread portion, the tread portion including a pair of tread edges, a crown profile extending between them in the tire axial direction, and a shoulder profile extending axially outward from the tread edges, the crown profile being formed by a first arc having a first radius of curvature on the tire equator side and a second arc having a second radius of curvature on the tread edge side, the shoulder profile being formed by a third arc having a single third radius of curvature different from the second radius of curvature, a belt layer being disposed inside the tread portion, and the belt end located at the outermost position in the tire axial direction of the belt layer being located axially outward of the tread edges and radially inward of the shoulder profile.

In the tire of the present invention, it is preferable that the crown profile and the shoulder profile are connected by a continuous point.

It is desirable for the second radius of curvature to be smaller than the first radius of curvature.

It is desirable for the third radius of curvature to be smaller than the second radius of curvature.

It is desirable that the first radius of curvature is 1000 to 2000 mm, the second radius of curvature is 200 to 400 mm, and the third radius of curvature is 20 to 40 mm.

In the tire of the present invention, it is preferable that the crown profile and the shoulder profile are connected by a discontinuous point.

In the tire of the present invention, it is preferable that the center of the third arc is located radially outward of the shoulder profile.

The present invention is a tire having a tread portion, the tread portion including a pair of tread edges, a crown profile extending between them in the tire axial direction, and a shoulder profile extending axially outward from the tread edges, the crown profile being formed by a first arc having a first radius of curvature on the tire equator side and a second arc having a second radius of curvature on the tread edge side, the shoulder profile being formed by a straight line, the crown profile and the shoulder profile being connected by a discontinuous point, a belt layer being disposed inside the tread portion, and the belt end located at the outermost position in the tire axial direction of the belt layer being located axially outward of the tread edges and radially inward of the shoulder profile.

In the tire of the present invention, it is preferable that the discontinuity be chamfered in an arc shape.

In the tire of the present invention, it is desirable that the axial distance between the belt end and the tread end is 5 to 20 mm.

In the tire of the present invention, the belt layer includes at least one belt ply and an edge band arranged radially outward of the belt ply, and it is preferable that the axially inner edge end of the edge band is located axially inward of the tread end.

In the tire of the present invention, the crown profile has a first position in the center of the tire axial direction and a second position on the outside in the tire axial direction, and the shoulder profile has the second position and a third position located on the tire radial outside of the belt end, and it is desirable that an angle of 10 to 30 degrees be formed between a first line connecting the first position and the second position and a second line connecting the second position and the third position.

It is desirable that the angle θ1 of the first straight line connecting the first position and the second position with respect to the tire axial direction is 2 to 4 degrees.

The belt layer preferably includes at least one belt ply, and the portion of the belt ply that is axially outboard of the tread edge extends parallel to an imaginary extension of the second arc of the crown profile.

The belt layer includes a first belt ply, a second belt ply arranged radially outward of the first belt ply, and a third belt ply arranged radially outward of the second belt ply, and it is desirable that the axial width of the second belt ply is smaller than the axial widths of the first belt ply and the third belt ply.

In the tire of the present invention, the tread portion includes a pair of tread ends, a crown profile extending between them in the tire axial direction, and a shoulder profile extending axially outward from the tread ends, the crown profile being formed by a first arc having a first radius of curvature on the tire equator side and a second arc having a second radius of curvature on the tread end side, and the shoulder profile being formed by a third arc or a straight line having a single third radius of curvature different from the second radius of curvature.

Since the crown profile of this type of tread portion is formed by at least one arc, the contact area is large when a load is applied to the tire, improving the steering stability of the tire. In addition, since the inflection point between the second and third arcs of this tread portion is located at the tread end, the contact area of the tread portion does not change excessively even when a large load is applied to the tire, improving the steering stability of the tire.

In the tire of the present invention, a belt layer is disposed inside the tread portion, and the belt end located at the outermost position in the tire axial direction of the belt layer is located axially outward of the tread end and radially inward of the shoulder profile.

Such a belt layer can reduce distortion of the belt ends because the shoulder profile is prevented from coming into contact with the ground even when a large load is applied to the tire. This reduces damage to the tread portion originating from the belt ends, improving the durability of the tire. Therefore, the tire of the present invention can achieve a good balance between good steering stability and durability.

1 is a cross-sectional view showing one embodiment of a tire of the present invention. FIG. 2 is a diagram showing a profile of the tire of FIG. 1. FIG. 1 is a schematic front view showing a vehicle on which a tire is mounted. FIG. 4 is a diagram showing a profile of a tire according to a second embodiment. FIG. 11 is a diagram showing a profile of a tire according to a third embodiment.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
1 is a tire meridian cross-sectional view showing a tire 1 in a normal state according to this embodiment. The tire 1 according to this embodiment is preferably used as a low-profile pneumatic tire suitable for racing vehicles. The tire 1 is not limited to being a pneumatic tire for racing vehicles, and may be used, for example, as a pneumatic tire for passenger cars or a tire for heavy loads.

Here, "normal state" means, in the case of a pneumatic tire, a state in which the tire 1 is mounted on a normal rim, adjusted to the normal internal pressure, and unloaded. Unless otherwise specified in this specification, the dimensions of each part of the tire 1 are values measured in the normal state.

A "genuine rim" is a rim that is determined for each tire by the standard system that includes the standard on which tire 1 is based. For example, in the case of JATMA, it is called a "standard rim," in the case of TRA, it is called a "design rim," and in the case of ETRTO, it is called a "measuring rim."

"Normal internal pressure" is the air pressure set for each tire by each standard in the standard system, including the standard on which tire 1 is based. For JATMA, it is the "maximum air pressure." For TRA, it is the maximum value listed in the table "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES." For ETRTO, it is the "INFLATION PRESSURE."

As shown in FIG. 1, the tire 1 of this embodiment includes a carcass 6 that extends from the tread portion 2 through the sidewall portion 3 to the bead core 5 of the bead portion 4, and a belt layer 7 that is disposed radially outward of the carcass 6 and inside the tread portion 2. It is preferable that the tire 1 has a ring-shaped bead core 5 embedded in the bead portion 4. The bead portion 4 has, for example, a bead apex rubber 8 with a triangular cross section that extends radially outward from the bead core 5.

The tread portion 2 of this embodiment includes a pair of tread ends Te (one of the tread ends Te is not shown), a crown profile Pc extending between them in the tire axial direction, and a shoulder profile Ps extending from the tread ends Te outward in the tire axial direction. The crown profile Pc and shoulder profile Ps of this embodiment represent the profiles of the tire 1 in a normal state.

Here, the "tread end Te" is the axially outermost contact point when the tire 1 in a normal state is loaded with a normal load and contacts a flat surface with a camber angle of 0°. The axial center position between this pair of tread ends Te is the tire equator C.

"Normal load" is the load that is determined for each tire by each standard in the standard system, including the standard on which tire 1 is based. For JATMA, it is "maximum load capacity." For TRA, it is the maximum value listed in the table "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES." For ETRTO, it is "LOAD CAPACITY."

It is preferable that the crown profile Pc is formed by at least one arc. The crown profile Pc of this embodiment is formed by a first arc A1 having a first radius of curvature R1 on the tire equator C side and a second arc A2 having a second radius of curvature R2 on the tread edge Te side. It is preferable that the second radius of curvature R2 is a radius different from the first radius of curvature R1. In this embodiment, the second radius of curvature R2 is smaller than the first radius of curvature R1.

Since the crown profile Pc of this type of tread portion 2 is formed by at least one arc, the contact area is large when a load is applied to the tire 1, which can improve the steering stability performance of the tire 1.

The shoulder profile Ps of this embodiment is formed by a third arc A3 having a single third radius of curvature R3. It is preferable that the third radius of curvature R3 is different from the first radius of curvature R1 and the second radius of curvature R2. The third radius of curvature R3 of this embodiment is smaller than the second radius of curvature R2.

In this type of tread portion 2, the inflection point between the second arc A2 and the third arc A3 is located at the tread end Te, so even when a large load acts on the tire 1, the contact area of the tread portion 2 does not change excessively, and the steering stability performance of the tire 1 can be further improved.

In this embodiment, the belt end 7e located at the outermost position in the tire axial direction of the belt layer 7 is located axially outboard of the tread end Te and radially inboard of the shoulder profile Ps.

Even when a large load acts on the tire 1, such a belt layer 7 suppresses contact of the shoulder profile Ps with the ground, so that distortion of the belt end 7e can be reduced. As a result, damage originating from the belt end 7e in the tread portion 2 is suppressed, and the durability performance of the tire 1 can be improved. Therefore, the tire 1 of this embodiment can achieve a good balance between good steering stability performance and durability performance.

In a more preferred embodiment, the carcass 6 is composed of at least one ply, and in this embodiment, one ply 6A. The carcass ply 6A includes a main body portion 6a that spans a pair of bead cores 5 (one of the bead cores 5 is not shown) in a toroidal shape, and folded-back portions 6b that are connected to both sides of the main body portion 6a and are folded back around the bead core 5 from the inside to the outside in the tire axial direction.

The carcass ply 6A includes carcass cords that are inclined at an angle of 75 to 90 degrees with respect to the tire equator C. For example, organic fiber cords or steel cords are used for the carcass cords.

The belt layer 7 includes at least one belt ply 9, three in this embodiment, and an edge band 10 arranged on the radially outer side of the belt ply 9. It is preferable that the belt ply 9 has a cut ply structure in which the axial end of the belt layer 7 is not folded back.

The belt ply 9 includes, for example, a first belt ply 9A arranged on the carcass 6 side, a second belt ply 9B arranged radially outward of the first belt ply 9A, and a third belt ply 9C arranged radially outward of the second belt ply 9B. Such a belt ply 9 can maintain the rigidity of the tread portion 2 even when a large load acts on the tire 1, and improve the steering stability performance of the tire 1.

In this embodiment, the axial width of the second belt ply 9B is smaller than the axial widths of the first belt ply 9A and the third belt ply 9C. The axial outer end of the second belt ply 9B is preferably located axially outward of the tread end Te. In this type of belt layer 7, the outer ends of all belt plies 9 are located axially outward of the tread end Te, so damage originating from the outer ends of all belt plies 9 is suppressed, and the durability of the tire 1 can be improved.

It is desirable that the belt ply 9 extends axially outward of the tread end Te approximately parallel to the imaginary extension line of the second arc A2 of the crown profile Pc. Such a belt layer 7 can reduce distortion at the outer end of the belt ply 9 and improve the durability of the tire 1.

The distance L in the tire axial direction between the belt end 7e and the tread end Te is preferably 5 to 20 mm. If the distance L is less than 5 mm, it becomes difficult to position the outer ends of all the belt plies 9 axially outboard of the tread end Te, and the durability of the tire 1 may not improve. If the distance L is greater than 20 mm, the shoulder profile Ps becomes a large arc, and the steering stability of the tire 1 may not improve.

The inner edge end 10e of the edge band 10 on the axially inner side of the tire is preferably located axially more inward than the tread end Te. In such an edge band 10, the inflection point between the crown profile Pc and the shoulder profile Ps, where stress is concentrated, is separated from the inner edge end 10e, so damage originating from the inner edge end 10e is suppressed, and the durability of the tire 1 can be improved.

The width W of the edge band 10 in the tire axial direction is preferably 20 to 40 mm. If the width W is smaller than 20 mm, the edge inner end 10e and the tread end Te are close to each other, and the durability of the tire 1 may not be improved. If the width W is larger than 40 mm, the weight of the tire 1 becomes large, and the steering stability of the tire 1 may not be improved.

The first radius of curvature R1 of the first arc A1 is preferably 1000 to 2000 mm. The second radius of curvature R2 of the second arc A2 is preferably 200 to 400 mm. The third radius of curvature R3 of the third arc A3 is preferably 20 to 40 mm. Such a tread portion 2 is suitable for achieving both steering stability and durability of the tire 1.

Figure 2 is a diagram showing the profile of the tire 1 in Figure 1. As shown in Figure 2, in the tire 1 of this embodiment, the crown profile Pc and the shoulder profile Ps are connected by a continuation point. Here, a "continuation point" is a point where the second arc A2 of the crown profile Pc and the third arc A3 of the shoulder profile Ps have a common tangent.

The crown profile Pc has, for example, a first position P1 at the center in the tire axial direction and a second position P2 on the outer side in the tire axial direction. In this embodiment, the first position P1 is the intersection of the first arc A1 and the tire equator C. In this embodiment, the second position P2 is the intersection of the second arc A2 and the tread edge Te, and is the above-mentioned continuous point.

The shoulder profile Ps has, for example, a second position P2 on the inside in the tire axial direction and a third position P3 on the outside in the tire axial direction. In this embodiment, the third position P3 is located on the third arc A3 on the outside in the tire radial direction of the belt end 7e. The shoulder profile Ps may extend further outward in the tire axial direction than the third position P3.

A first straight line L1 can be drawn on the crown profile Pc, connecting the first position P1 and the second position P2. The angle θ1 of the first straight line L1 with respect to the tire axial direction is desirably greater than the negative camber angle θn (shown in FIG. 3) described below. The angle θ1 is preferably 2° or greater. Such a crown profile Pc reduces distortion of the belt end 7e even when the tire 1 is mounted on a vehicle V (shown in FIG. 3) with a large negative camber angle θn, improving the durability of the tire 1.

A second straight line L2 can be drawn on the shoulder profile Ps, connecting the second position P2 and the third position P3. The first straight line L1 and the second straight line L2 preferably have an angle θ2 of 10 to 30°. If the angle θ2 is less than 10°, the ground contact range of the tread portion 2 changes excessively when a large load acts on the tire 1, and the steering stability performance of the tire 1 may not be improved. If the angle θ2 is greater than 30°, the axial distance L between the belt end 7e and the tread end Te becomes small, and the durability performance of the tire 1 may not be improved.

Figure 3 is a schematic front view of a vehicle V equipped with a tire 1. The vehicle V is, for example, a racing vehicle. As shown in Figure 3, the tire 1 is equipped on the vehicle V with a negative camber angle θn. Such a tire 1 can provide excellent steering stability even when the vehicle V is traveling at high speeds.

The negative camber angle θn of the vehicle V is preferably 2° or more. When such a vehicle V turns a corner at high speed, the contact area of the tire 1 becomes large, allowing it to exhibit excellent grip performance.

Figure 4 is a diagram showing the profile of a tire 11 of the second embodiment. The same components as those of the above-mentioned embodiment are given the same reference numerals, and their description is omitted. As shown in Figure 4, the tread portion 12 of the tire 11 of this embodiment includes a crown profile Pc that extends axially between a pair of tread ends Te, and a shoulder profile Ps2 that extends axially outward from the tread ends Te.

The shoulder profile Ps2 in this embodiment is formed of a third arc A13 having a single third radius of curvature R13 different from the second radius of curvature R2. The center of the third arc A13 in this embodiment is located radially outward of the shoulder profile Ps2. Such a shoulder profile Ps2 is unlikely to come into contact with the ground even when a large load acts on the tire 1, and can reduce distortion of the belt end 7e and improve the durability of the tire 11.

In the tire 11 of this embodiment, the crown profile Pc and the shoulder profile Ps2 are connected by a discontinuous point. Here, the "discontinuous point" refers to a point where the second arc A2 of the crown profile Pc and the third arc A13 of the shoulder profile Ps2 are connected without having a common tangent. With such a tread portion 12, there is no risk of the ground contact area of the tread portion 12 changing even when a large load is applied to the tire 11, and the steering stability performance of the tire 11 can be improved.

The discontinuities are preferably chamfered in an arc shape with a radius of curvature of 10 mm or less. Such a tread portion 12 suppresses damage originating from the discontinuities, and can improve the durability of the tire 11. Therefore, the tire 11 of the second embodiment can achieve both good steering stability and durability at a high level.

Figure 5 is a diagram showing the profile of a tire 13 of the third embodiment. The same components as those of the above-mentioned embodiment are given the same reference numerals, and their description is omitted. As shown in Figure 5, the tread portion 14 of the tire 13 of this embodiment includes a crown profile Pc that extends axially between a pair of tread ends Te, and a shoulder profile Ps3 that extends axially outward from the tread ends Te.

The shoulder profile Ps3 in this embodiment is formed as a straight line. Therefore, the shoulder profile Ps3 in this embodiment is equal to the second straight line L2 (shown in FIG. 2). Such a shoulder profile Ps2 is unlikely to come into contact with the ground even when a large load acts on the tire 1, and it is possible to reduce distortion of the belt end 7e and improve the durability of the tire 1.

In the tire 13 of this embodiment, as in the second embodiment, the crown profile Pc and the shoulder profile Ps2 are connected by a discontinuous point. With such a tread portion 14, there is no risk of the ground contact area of the tread portion 14 changing even when a large load acts on the tire 13, and the steering stability performance of the tire 13 can be improved.

As in the second embodiment, the discontinuities are preferably chamfered in an arc shape with a radius of curvature of 10 mm or less. Such a tread portion 14 suppresses damage originating from the discontinuities, improving the durability of the tire 13. Therefore, the tire 13 of the third embodiment can achieve both good steering stability and durability at a high level.

The above describes in detail a particularly preferred embodiment of the present invention, but the present invention is not limited to the above-described embodiment and can be modified in various ways.

Pneumatic racing tires of the examples having the basic structure of FIG. 1 and the profiles of FIG. 2, FIG. 4, and FIG. 5 were prototyped based on the specifications in Tables 1 and 2. In addition, as a comparative example, a pneumatic racing tire in which the belt end is located radially inward of the tread end was prototyped based on the specifications in Table 1. The steering stability and durability performance of the prototype tires of these examples and comparative examples were evaluated. The common specifications and test methods of each prototype tire are as follows.

<Common specifications>
Tire size: 290/680R18
Rim size: 18 x 11.0J
Air pressure: 200kPa
First curvature radius: 1500 mm
Second curvature radius: 300 mm
Third curvature radius: 30 mm (except for Examples 15 and 16)

<Handling stability>
Each prototype tire was mounted on all wheels of a 3.5-liter rear-wheel drive vehicle with a negative camber angle of 3°, and one test driver was in the vehicle to drive on a dry paved course, and the vehicle's responsiveness to steering was evaluated by the test driver's senses. The results were expressed as an index with Comparative Example 1 set at 100, and the higher the value, the more excellent the handling stability performance.

<Durability>
Each prototype tire was attached to a drum testing machine with a negative camber angle of 3°, and the running time until the tire was destroyed when a vertical load of 7 kN was applied and the tire was run at a speed of 200 km/h was measured. The results are expressed as an index with Comparative Example 1 being 100, and the higher the value, the more excellent the durability performance.

The test results are shown in Tables 1 and 2.

The test results confirmed that the tire of the embodiment had a better balance of steering stability and durability than the comparative example.

Reference Signs List 1 Tire 2 Tread portion 7 Belt layer 7e Belt end Pc Crown profile Ps Shoulder profile A1 First circular arc A2 Second circular arc A3 Third circular arc

Claims (16)

A tire having a tread portion,
The tread portion includes a pair of tread ends, a crown profile extending therebetween in the tire axial direction, and a shoulder profile extending from the tread ends to an outer side in the tire axial direction,
The crown profile is formed by a first circular arc having a first radius of curvature on a tire equator side and a second circular arc having a second radius of curvature on a tread end side,
the shoulder profile is defined by a third arc having a single third radius of curvature different from the second radius of curvature;
A belt layer is disposed inside the tread portion,
a belt end of the belt layer positioned outermost in the tire axial direction is positioned outer than the tread end in the tire axial direction and inner in the tire radial direction of the shoulder profile,
The first radius of curvature is 1000 to 2000 mm;
The second radius of curvature is 200 to 400 mm;
the third radius of curvature is between 20 and 40 mm;
The crown profile and the shoulder profile are connected by a discontinuity.
tire. The tire according to claim 1 , wherein a center of the third arc is located radially outward of the shoulder profile . A tire having a tread portion,
The tread portion includes a pair of tread ends, a crown profile extending therebetween in the tire axial direction, and a shoulder profile extending from the tread ends to an outer side in the tire axial direction,
The crown profile is formed by a first circular arc having a first radius of curvature on a tire equator side and a second circular arc having a second radius of curvature on a tread end side,
The shoulder profile is formed by a straight line,
the crown profile and the shoulder profile are connected by a discontinuity;
A belt layer is disposed inside the tread portion,
a belt end of the belt layer located at the outermost side in the tire axial direction is located at the outer side of the tread end in the tire axial direction and at the inner side of the shoulder profile in the tire radial direction,
The discontinuity is chamfered in an arc.
tire. 3. The tire of claim 1 or 2, wherein the discontinuity is chamfered in an arcuate shape. 5. The tire according to claim 1, wherein the distance in the tire axial direction between said belt end and said tread end is 5 to 20 mm. The belt layer includes at least one belt ply and an edge band disposed on an outer side of the belt ply in the tire radial direction,
The tire according to claim 1 , wherein an inner edge end of the edge band on an axially inner side of the tire is positioned axially more inner than the tread end. The crown profile has an axially central first location and an axially outer second location,
The shoulder profile has the second position and a third position located outwardly of the belt end in the tire radial direction,
7. The tire according to claim 1, wherein a first line connecting the first position and the second position and a second line connecting the second position and the third position have an angle of 10 to 30 degrees. The tire according to claim 7, wherein an angle θ1 of a first straight line connecting the first position and the second position with respect to the tire axial direction is 2 to 4 degrees. The belt layer includes at least one belt ply,
The tire according to claim 1 , wherein a portion of the belt ply that is axially outboard of the tread end extends parallel to an imaginary extension line of the second arc of the crown profile . the belt layer includes a first belt ply, a second belt ply disposed on the outer side of the first belt ply in the tire radial direction, and a third belt ply disposed on the outer side of the second belt ply in the tire radial direction,
The tire according to claim 1 , wherein an axial width of the second belt ply is smaller than axial widths of the first belt ply and the third belt ply . A tire having a tread portion,
The tread portion includes a pair of tread ends, a crown profile extending therebetween in the tire axial direction, and a shoulder profile extending from the tread ends to an outer side in the tire axial direction,
The crown profile is formed by a first circular arc having a first radius of curvature on a tire equator side and a second circular arc having a second radius of curvature on a tread end side,
the shoulder profile is defined by a third arc having a single third radius of curvature different from the second radius of curvature;
A belt layer is disposed inside the tread portion,
a belt end of the belt layer located at the outermost side in the tire axial direction is located at the outer side of the tread end in the tire axial direction and at the inner side of the shoulder profile in the tire radial direction,
the crown profile and the shoulder profile are connected by a discontinuity;
The center of the third arc is located radially outward of the shoulder profile.
tire. A tire having a tread portion,
The tread portion includes a pair of tread ends, a crown profile extending therebetween in the tire axial direction, and a shoulder profile extending from the tread ends to an outer side in the tire axial direction,
The crown profile is formed by a first circular arc having a first radius of curvature on a tire equator side and a second circular arc having a second radius of curvature on a tread end side,
the shoulder profile is defined by a third arc having a single third radius of curvature different from the second radius of curvature;
A belt layer is disposed inside the tread portion,
a belt end of the belt layer located at the outermost side in the tire axial direction is located at the outer side of the tread end in the tire axial direction and at the inner side of the shoulder profile in the tire radial direction,
the crown profile and the shoulder profile are connected by a discontinuity;
The discontinuity is chamfered in an arc.
tire. A tire having a tread portion,
The tread portion includes a pair of tread ends, a crown profile extending therebetween in the tire axial direction, and a shoulder profile extending from the tread ends to an outer side in the tire axial direction,
The crown profile is formed by a first circular arc having a first radius of curvature on a tire equator side and a second circular arc having a second radius of curvature on a tread end side,
the shoulder profile is defined by a third arc having a single third radius of curvature different from the second radius of curvature;
A belt layer is disposed inside the tread portion,
a belt end of the belt layer located at the outermost side in the tire axial direction is located at the outer side of the tread end in the tire axial direction and at the inner side of the shoulder profile in the tire radial direction,
The crown profile has an axially central first location and an axially outer second location,
The shoulder profile has the second position and a third position located outwardly of the belt end in the tire radial direction,
A first straight line connecting the first position and the second position and a second straight line connecting the second position and the third position have an angle of 10 to 30 degrees.
tire. A tire having a tread portion,
The tread portion includes a pair of tread ends, a crown profile extending therebetween in the tire axial direction, and a shoulder profile extending from the tread ends to an outer side in the tire axial direction,
The crown profile is formed by a first circular arc having a first radius of curvature on a tire equator side and a second circular arc having a second radius of curvature on a tread end side,
the shoulder profile is defined by a third arc having a single third radius of curvature different from the second radius of curvature;
A belt layer is disposed inside the tread portion,
a belt end of the belt layer located at the outermost side in the tire axial direction is located at the outer side of the tread end in the tire axial direction and at the inner side of the shoulder profile in the tire radial direction,
The belt layer includes at least one belt ply,
A portion of the belt ply that is axially outward of the tread end extends parallel to an imaginary extension line of the second arc of the crown profile.
tire. A tire having a tread portion,
The tread portion includes a pair of tread ends, a crown profile extending therebetween in the tire axial direction, and a shoulder profile extending from the tread ends to an outer side in the tire axial direction,
The crown profile is formed by a first circular arc having a first radius of curvature on a tire equator side and a second circular arc having a second radius of curvature on a tread end side,
The shoulder profile is formed by a straight line,
the crown profile and the shoulder profile are connected by a discontinuity;
A belt layer is disposed inside the tread portion,
a belt end of the belt layer positioned outermost in the tire axial direction is positioned outer than the tread end in the tire axial direction and inner in the tire radial direction of the shoulder profile,
The crown profile has an axially central first location and an axially outer second location,
The shoulder profile has the second position and a third position located outwardly of the belt end in the tire radial direction,
A first straight line connecting the first position and the second position and a second straight line connecting the second position and the third position have an angle of 10 to 30 degrees.
tire. A tire having a tread portion,
The tread portion includes a pair of tread ends, a crown profile extending therebetween in the tire axial direction, and a shoulder profile extending from the tread ends to an outer side in the tire axial direction,
The crown profile is formed by a first circular arc having a first radius of curvature on a tire equator side and a second circular arc having a second radius of curvature on a tread end side,
The shoulder profile is formed by a straight line,
the crown profile and the shoulder profile are connected by a discontinuity;
A belt layer is disposed inside the tread portion,
a belt end of the belt layer positioned outermost in the tire axial direction is positioned outer than the tread end in the tire axial direction and inner in the tire radial direction of the shoulder profile,
The belt layer includes at least one belt ply,
A portion of the belt ply that is axially outward of the tread end extends parallel to an imaginary extension line of the second arc of the crown profile.
tire.

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