Pneumatic tires

Abstract

The present invention provides a pneumatic tire that can achieve a high degree of both handling stability and durability during high-speed driving. The pneumatic tire (1) comprises: a carcass (6) extending between a pair of bead portions (4) through a tread portion (2) and a pair of sidewall portions (3); a belt layer (7) composed of at least two belt cords (7A, 7B) arranged on the tire radially outer side of the carcass; a band layer (8) arranged on the tire radially outer side of the belt layer; and a belt end rubber (9) arranged between the belt layer and the band layer in a manner that includes the tire axial outer end (7e) of the belt layer. The belt layer includes at least one full belt (8A) and an end belt (8B) covering the outer end of the belt layer. The end belt includes an organic fiber cord. The restraining force of the organic fiber cord of the end belt at a position on the tire radially outer side of the outer end of the belt layer is 5 to 35N.

Description

Technical Field

[0001] The present invention relates to a pneumatic tire including a carcass, a belt layer, and a band layer. Background Art

[0002] Conventionally, pneumatic tires are known that include a carcass, a belt layer disposed radially outward of the carcass, and a band layer disposed radially outward of the belt layer. For example, Patent Document 1 below proposes a tire that achieves both durability and grip performance by including a first reinforcing rubber layer between the belt layer and the band layer, covering the outer end of the belt layer in the tire's axial direction.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2019-006203

[0004] However, in the tire of Patent Document 1, the first reinforcing rubber layer becomes thinner due to the restraining force of the belt layer, and the outer end of the belt layer may pass through the first reinforcing rubber layer and damage the belt layer during high-speed driving. Therefore, further improvement is urgently needed in the tire of Patent Document 1 in terms of balancing steering stability and durability. Summary of the Invention

[0005] The present invention has been made in view of the above-mentioned actual situation, and a main object of the present invention is to provide a pneumatic tire capable of achieving a high degree of both steering stability and durability during high-speed running.

[0006] The present invention is a pneumatic tire, which is characterized in that it comprises: a carcass extending between a pair of bead portions in a manner passing through a tread portion and a pair of sidewall portions; a belt layer composed of at least two belt cords arranged on the tire radially outer side of the carcass; a band layer arranged on the tire radially outer side of the belt layer; and belt end rubber arranged between the belt layer and the band layer in a manner including a position of the tire axially outer end of the belt layer, the belt layer including an end belt covering the outer end of the belt layer and at least one full belt, the end belt including organic fiber cords, the restraint force of the organic fiber cords of the end belt at a position on the tire radially outer side of the outer end of the belt layer is 5 to 35N.

[0007] In the pneumatic tire of the present invention, preferably, in a tire cross-section including the tire rotation axis, the tread portion includes a pair of tread ends and a tread profile portion extending between the tread ends, and for the tread profile portion, the first straight line connecting the center position of the tire axial direction and the tread ends has an angle of more than 2° relative to the tire axial direction.

[0008] In the pneumatic tire of the present invention, it is preferred that the above-mentioned belt ply includes a first belt ply and a second belt ply arranged on the radially outer side of the tire of the above-mentioned first belt ply, and the above-mentioned outer end of the above-mentioned belt layer includes the first outer end of the above-mentioned first belt ply and the second outer end of the above-mentioned second belt ply, and the above-mentioned second outer end is located on the axially outer side of the tire than the above-mentioned tread end and on the axially inner side of the tire than the above-mentioned first outer end.

[0009] In the pneumatic tire of the present invention, it is preferable that a distance between the second outer end and the tread end in the tire axial direction is 5 to 20 mm.

[0010] In the pneumatic tire of the present invention, the tread portion preferably includes an outer contour portion extending from the tread end to the outer side in the tire axial direction. For the outer contour portion, the angle of the second straight line connecting the tread end and the outer position of the second outer end in the tire radial direction relative to the first straight line is 10 to 30 degrees.

[0011] In the pneumatic tire of the present invention, it is preferable that the belt end rubber extends from a position axially outward from the first outer end to a position axially inward from the second outer end.

[0012] In the pneumatic tire of the present invention, it is preferable that the width of the belt end rubber in the tire axial direction is 10 to 50 mm.

[0013] In the pneumatic tire of the present invention, it is preferable that the width of the end band in the tire axial direction is 20 to 50 mm.

[0014] In the pneumatic tire of the present invention, it is preferable that the distance between the outer end of the belt layer and the band layer in the tire radial direction is 0.2 to 2.0 mm.

[0015] In the pneumatic tire of the present invention, the total fineness of the organic fiber cord is preferably 900 to 5500 dtex.

[0016] In the pneumatic tire of the present invention, the number of the organic fiber cords woven into the tire per 5 cm is preferably 30 to 60.

[0017] In the pneumatic tire of the present invention, there is a belt end rubber arranged between the above-mentioned belt layer and the band layer in a manner so as to include the position of the outer end of the belt layer in the tire axial direction, the above-mentioned band layer includes at least one full belt and an end band covering the above-mentioned outer end of the above-mentioned belt layer, the above-mentioned end band includes organic fiber cords, and the restraint force of the above-mentioned organic fiber cords of the above-mentioned end band at the position outside the above-mentioned outer end of the belt layer in the tire radial direction is 5 to 35N.

[0018] Such a pneumatic tire utilizes a belt layer to enhance rigidity and exhibit excellent handling stability. Furthermore, the restraining force of the end belts is low, preventing the rubber at the belt ends from being compressed and thinned, thereby reliably preventing contact between the outer ends of the belt layer and the belt layer. Consequently, the pneumatic tire of the present invention achieves a high balance between high-speed handling stability and durability. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a cross-sectional view showing one embodiment of the pneumatic tire of the present invention.

[0020] Figure 2 It is a partial cross-sectional view of the tread portion.

[0021] Description of Reference Numerals

[0022] 1…pneumatic tire; 2…carcass; 3…sidewall; 4…bead; 6…carcass; 7…belt; 7A, 7B…belt fabric; 8…belt layer; 8A…full belt; 8B…end belt; 9…belt end rubber. DETAILED DESCRIPTION

[0023] Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings. Figure 1 This is a cross-sectional view showing a pneumatic tire 1 (hereinafter sometimes referred to simply as "tire 1") according to this embodiment in its normal state, including the tire's rotation axis (not shown). Tire 1 according to this embodiment is suitable for use as a low-profile tire suitable for racing vehicles. However, tire 1 is not limited to low-profile tires for racing.

[0024] Here, "normal state" refers to the unloaded state in which the tire 1 is assembled on a normal rim and adjusted to a normal internal pressure. In addition, in this specification, unless otherwise specified, the dimensions of each part of the tire 1 are values ​​measured in the normal state.

[0025] "Regulated rims" refer to rims with specifications specified for each tire, if a specification system exists that includes the specifications to which the tire 1 conforms. For example, JATMA refers to "standard rims," ​​TRA refers to "design rims," ​​and ETRTO refers to "measuring rims." If a specification system does not exist that includes the specifications to which the tire 1 conforms, "regular rims" refer to rims specified for each tire by the manufacturer or the like.

[0026] "Regulated internal pressure" refers to the air pressure specified for each tire according to a standard system, if a system exists that includes the standard to which the tire 1 conforms. For JATMA, this refers to the "maximum air pressure," for TRA, it refers to the maximum value listed in the table "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES," and for ETRTO, it refers to "INFLATION PRESSURE." If a system does not exist that includes the standard to which the tire 1 conforms, "regulated internal pressure" refers to the air pressure specified for each tire by the manufacturer, etc.

[0027] like Figure 1 As shown, the tire 1 of this embodiment includes a tread portion 2 that rotates to contact the ground, a pair of sidewall portions 3 located on both sides of the tread portion 2 in the tire axial direction, and a pair of bead portions 4 located radially inward of the sidewall portions 3 .

[0028] The tire 1 of this embodiment includes a carcass 6, a belt layer 7 arranged on the tire radially outer side of the carcass 6, and a band layer 8 arranged on the tire radially outer side of the belt layer 7. The tire 1 of this embodiment further includes a belt end rubber 9 arranged between the belt layer 7 and the band layer 8 so as to include the position of the outer end 7e of the belt layer 7 in the tire axial direction.

[0029] The carcass 6 is preferably composed of at least one carcass ply 6A extending between the pair of bead portions 4, through the tread portion 2, and through the pair of sidewall portions 3. Although not shown in the figure, the carcass ply 6A may be two or more. Furthermore, the axial end of the carcass ply 6A may extend from the bead portion 4 to the outside in the tire radial direction, for example, to the vicinity of the tread portion 2, or may terminate at the bead portion 4 without being wound up.

[0030] The carcass ply 6A includes, for example, carcass cords arranged at an angle of 60 to 90 degrees with respect to the tire circumferential direction. The carcass cords are preferably formed of organic fibers such as nylon, polyester, rayon, and aramid fibers.

[0031] Figure 2 2 is a partial cross-sectional view of the tread portion 2. Figure 2 As shown, the belt layer 7 is composed of at least two belt plies 7A and 7B, two belt plies in this embodiment. The belt plies 7A and 7B include, for example, a first belt ply 7A and a second belt ply 7B positioned radially outward of the first belt ply 7A. This tire 1 can achieve enhanced rigidity due to the belt layer 7 and exhibit excellent steering stability.

[0032] The belt plies 7A and 7B include belt cords arranged at an angle of, for example, 10 to 45 degrees relative to the tire circumferential direction. Highly elastic cords, such as steel cords, are preferably used as the belt cords. The belt cords of the first belt ply 7A and the second belt ply 7B are preferably inclined in opposite directions.

[0033] The belt layer 8 includes at least one full belt 8A, in this embodiment, one full belt, and an end belt 8B covering the outer end 7e of the belt layer 7. The full belt 8A and the end belt 8B in this embodiment each include organic fiber cords. The full belt 8A and the end belt 8B each preferably have organic fiber cords arranged at an angle of 5° or less relative to the tire circumferential direction. Examples of organic fiber cords include nylon, rayon, and aramid fibers.

[0034] The restraint force of the organic fiber cord of the end band 8B of this embodiment at the outer side of the outer end 7e of the belt layer 7 in the tire radial direction is 5 to 35 N. The restraint force of one organic fiber cord of the end band 8B can be measured by removing only the end band 8B from the tire 1.

[0035] In such a tire 1, the restraining force of the end band 8B is small, so the belt end rubber 9 is not compressed and thinned, and the outer end 7e of the belt layer 7 can be reliably suppressed from contacting the band layer 8. Therefore, the tire 1 of this embodiment can achieve a high degree of both steering stability and durability during high-speed driving.

[0036] By setting the restraining force of the organic fiber cords of the end band 8B to 5N or greater, the number of organic fiber cords in the end band 8B can be reduced, contact of the organic fiber cords in the end band 8B can be suppressed, and the durability of the tire 1 can be improved. From this perspective, the restraining force of the organic fiber cords of the end band 8B is preferably 10N or greater, and more preferably 15N or greater.

[0037] By setting the restraining force of the organic fiber cords of the end band 8B to 35 N or less, it is possible to reliably suppress contact between the outer end 7 e of the belt layer 7 and the band layer 8, thereby improving the durability of the tire 1. From this perspective, the restraining force of the end band 8B is preferably 30 N or less, and more preferably 25 N or less.

[0038] As a more preferred embodiment, the belt layer 7 adopts a cut-cord structure in which the outer end 7e thereof is not folded back. The outer end 7e of the belt layer 7 in this embodiment includes a first outer end 7a of a first belt cord 7A and a second outer end 7b of a second belt cord 7B.

[0039] The second outer end 7b is preferably located axially outward from the tread end Te and axially inward from the first outer end 7a. Such an outer end 7e is not in contact with the ground when the tire 1 is in contact with the ground, thereby reducing deformation of the outer end 7e and improving the durability of the tire 1.

[0040] Here, the "tread end Te" refers to the axially outermost contact point of the tire when a normal load is applied to the normal tire 1 and the tire contacts a flat surface at a camber angle of 0. The tire equator C is the center point between the pair of tread ends Te.

[0041] "Normal load" refers to the load specified for each tire according to a standard system, if a standard system exists that includes the standard to which the tire 1 conforms. For JATMA, this refers to the "maximum load capacity," for TRA, it refers to the maximum value listed in the "TIRELOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES" table, and for ETRTO, it refers to "LOAD CAPACITY." If a standard system does not exist that includes the standard to which the tire 1 conforms, the "Normal load" refers to the load specified for each tire by the manufacturer, etc.

[0042] The axial distance d1 between the second outer end 7b and the tread end Te is preferably 5 to 20 mm. By setting the distance d1 to 5 mm or greater, the second outer end 7b can be reliably prevented from contacting the ground when the tire 1 contacts the ground, thereby improving the durability of the tire 1. From this perspective, the distance d1 is more preferably 7 mm or greater, and even more preferably 8 mm or greater.

[0043] By setting the distance d1 to 20 mm or less, a sufficient contact patch width can be ensured, thereby improving the steering stability of the tire 1. From this viewpoint, the distance d1 is more preferably 15 mm or less, and even more preferably 10 mm or less.

[0044] like Figure 1 As shown, in a tire cross-section encompassing the tire's rotational axis, the tread portion 2 of this embodiment comprises a pair of tread ends Te, a tread profile portion 2a extending between the tread ends Te, and an outer profile portion 2b extending axially outward from the tread ends Te. The tread profile portion 2a and the outer profile portion 2b are each preferably formed by at least one circular arc. This tread portion 2 exhibits smooth axial shape changes, which is ideal for achieving a balance between the tire's handling stability and durability.

[0045] In the tread profile portion 2a, the angle θ1 of the first straight line L1 connecting the tire's axial center position P1 and the tread end Te relative to the tire's axial direction is preferably 2° or greater, more preferably 2.5° or greater, and even more preferably 3° or greater. With such a tread profile portion 2a, deformation at the tread end Te is small, further reducing deformation of the outer end 7e of the belt layer 7, thereby further improving the durability of the tire 1.

[0046] like Figure 2 As shown, in the outer contour portion 2b, an angle θ2 of a second straight line L2 connecting the tread end Te and the outer position P2 of the second outer end 7b in the tire radial direction with respect to the first straight line L1 is preferably 10 to 30°.

[0047] Setting the angle θ2 to 10° or greater can reduce deformation of the second outer end 7b when a large load acts on the tire 1, thereby improving the durability of the tire 1. From this viewpoint, the angle θ2 is more preferably 12° or greater, and even more preferably 15° or greater.

[0048] Setting the angle θ2 to 30° or less can reduce deformation of the second outer end 7b during molding, thereby improving the durability of the tire 1. From this viewpoint, the angle θ2 is more preferably 25° or less, and even more preferably 20° or less.

[0049] The band layer 8 of this embodiment has an end band 8B disposed between the full band 8A and the belt layer 7. It is preferable that the band layer 8 has an axially outer belt end 8e aligned with the first outer end 7a.

[0050] The belt ends 8e of this embodiment include a first belt end 8a of the full belt 8A and a second belt end 8b of the end belt 8B. Both the first and second belt ends 8a, 8b are preferably aligned with the first outer end 7a. This band layer 8 reliably covers the outer end 7e of the belt layer 7 while also preventing it from becoming excessively large. This is therefore suitable for achieving a balance between the handling stability and durability of the tire 1.

[0051] The tire axial width W1 of the end band 8B is preferably 20 to 50 mm. A width W1 of 20 mm or greater ensures reliable coverage of the outer end 7e of the belt layer 7, thereby improving the durability of the tire 1. From this perspective, the width W1 is more preferably 25 mm or greater, and even more preferably 30 mm or greater.

[0052] Setting the width W1 to 50 mm or less can reduce the overall weight, thereby contributing to lightweighting of the tire 1. From this viewpoint, the width W1 is more preferably 45 mm or less, and even more preferably 40 mm or less.

[0053] The third belt end 8c of the end belt 8B of this embodiment, located axially inward of the tire, is located axially inward of the tread end Te. Such an end belt 8B can increase the restraining force during contact with the ground, thereby reducing deformation of the outer end 7e of the belt layer 7 and improving the durability of the tire 1.

[0054] The total fineness of the organic fiber cord is preferably 900 to 5500 dtex. Here, the total fineness of the organic fiber cord defines the actual thickness of the organic fiber cord. In the case of an organic fiber cord formed by twisting a plurality of raw yarns, the total fineness is the sum of the finenesses of the raw yarns.

[0055] By setting the total fineness to 900 dtex or more, deformation of the outer end 7e of the belt layer 7 can be reduced, thereby improving the durability of the tire 1. From this viewpoint, the total fineness is more preferably 1500 dtex or more, and even more preferably 2000 dtex or more.

[0056] By setting the total fineness to 5500 dtex or less, energy loss can be reduced and the steering stability of the tire 1 can be improved. From this viewpoint, the total fineness is more preferably 5000 dtex or less, and even more preferably 4500 dtex or less.

[0057] For organic fiber cords, the number of cords woven per 5 cm, or the density, is preferably 30 to 60. A density of 30 or greater can reduce deformation of the outer ends 7e of the belt layer 7, thereby improving the durability of the tire 1. From this perspective, the density is more preferably 35 or greater, and even more preferably 40 or greater.

[0058] By setting the density number to 60 or less, energy loss can be reduced and the steering stability of the tire 1 can be improved. From this viewpoint, the density number is more preferably 55 or less, and even more preferably 50 or less.

[0059] The belt end rubber 9 of this embodiment extends from a position axially outward from the first outer end 7a to a position axially inward from the second outer end 7b. In other words, the belt end rubber 9 has the first end 9a on the outside of the tire axial direction located axially outward from the first outer end 7a, and the second end 9b on the inside of the tire axial direction located axially inward from the second outer end 7b.

[0060] The distance d2 between the first end 9a and the first outer end 7a in the tire axial direction is preferably 5 to 45 mm. A distance d2 of 5 mm or greater ensures reliable coverage of the first outer end 7a, thereby improving the durability of the tire 1. From this perspective, the distance d2 is more preferably 7 mm or greater, and even more preferably 10 mm or greater.

[0061] By setting the distance d2 to 45 mm or less, it is possible to suppress an excessive decrease in rigidity, thereby improving the steering stability of the tire 1. From this viewpoint, the distance d2 is more preferably 40 mm or less, and even more preferably 30 mm or less.

[0062] The distance d3 between the second end 9b and the second outer end 7b in the tire axial direction is preferably 5 to 45 mm. A distance d3 of 5 mm or greater ensures reliable coverage of the second outer end 7b, thereby improving the durability of the tire 1. From this perspective, the distance d3 is preferably 7 mm or greater, and more preferably 10 mm or greater.

[0063] By setting the distance d3 to 45 mm or less, it is possible to suppress an excessive decrease in rigidity, thereby improving the steering stability of the tire 1. From this viewpoint, the distance d3 is more preferably 40 mm or less, and even more preferably 30 mm or less.

[0064] The axial width W2 of the belt end rubber 9 is preferably 10 to 50 mm. A width W2 of 10 mm or greater ensures reliable coverage of the outer end 7e of the belt layer 7, thereby improving the durability of the tire 1. From this perspective, the width W2 is more preferably 15 mm or greater, and even more preferably 20 mm or greater.

[0065] By setting the width W2 to 50 mm or less, it is possible to suppress an excessive decrease in rigidity, thereby improving the steering stability of the tire 1. From this viewpoint, the width W2 is more preferably 45 mm or less, and even more preferably 40 mm or less.

[0066] The belt end rubber 9 preferably has a loss tangent tanδ at 70°C of 0.05 to 0.18. A loss tangent tanδ of 0.05 or greater at 70°C can improve impact absorption, thereby enhancing the ride comfort of the tire 1. From this perspective, the loss tangent tanδ at 70°C is more preferably 0.07 or greater, and even more preferably 0.09 or greater.

[0067] Setting the loss tangent tanδ at 70°C to 0.18 or less can suppress excessive heat generation, thereby improving the durability of the tire 1. From this viewpoint, the loss tangent tanδ at 70°C is more preferably 0.16 or less, and even more preferably 0.14 or less.

[0068] Here, the loss tangent tan δ is a value measured using a dynamic viscoelasticity measuring apparatus under the following conditions in accordance with the provisions of JIS-K6394.

[0069] Initial deformation: 10%

[0070] Amplitude: ±1%

[0071] Frequency: 10Hz

[0072] Deformation Mode: Stretch

[0073] Measurement temperature: 70°C

[0074] The distance d4 between the outer end 7e of the belt layer 7 and the belt ply 8 in the tire radial direction is preferably 0.2 to 2.0 mm. The distance d4 between the outer end 7e and the belt ply 8 is the distance in the tire radial direction between the first outer end 7a and the second outer end 7b and the belt ply 8, and preferably includes the distance in the tire radial direction between the first belt ply 7A located between the first outer end 7a and the second outer end 7b and the belt ply 8.

[0075] Setting the distance d4 to 0.2 mm or more reliably prevents the outer end 7e of the belt layer 7 from contacting the band layer 8, thereby improving the durability of the tire 1. From this viewpoint, the distance d4 is more preferably 0.3 mm or more, and even more preferably 0.4 mm or more.

[0076] By setting the distance d4 to 2.0 mm or less, the rigidity of the belt layer 7 near the outer end 7e can be increased, thereby improving the steering stability of the tire 1. From this viewpoint, the distance d4 is more preferably 1.5 mm or less, and even more preferably 1.0 mm or less.

[0077] As mentioned above, although the particularly preferred embodiment of the present invention was described in detail, the present invention is not limited to the above-mentioned embodiment, and can be implemented in various modified forms.

[0078] [Example]

[0079] Based on the specifications in Tables 1 to 4, we have produced Figure 1 These prototype tires were tested for handling stability and durability. The common specifications and testing methods for each prototype tire are as follows.

[0080] <Common Specifications>

[0081] Tire size: 290 / 680R18

[0082] Rim size: 18×11.0J

[0083] Air pressure: 200kPa

[0084] <Handling stability>

[0085] Each prototype tire was mounted on all wheels of a 3.5-liter rear-wheel drive vehicle with a negative camber angle of 3°. The vehicle's responsiveness to steering control was evaluated using the driver's sensory perception while a single test driver was seated on a dry, paved track. The results were displayed as an index, with Comparative Example 1 being 100, with larger values ​​indicating superior steering stability.

[0086] Durability

[0087] The duration until tire failure was measured for each prototype tire, mounted on a drum tester at a negative camber angle of 3° and loaded with a longitudinal load of 7 kN at a speed of 200 km / h. The results are displayed as an index, with Comparative Example 1 being 100, with larger values ​​indicating superior durability.

[0088] The test results are shown in Tables 1 to 4.

[0089]

Table 1

[0090] Comparative Example 1 Comparative Example 2 Comparative Example 3 Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Constraint force of organic fiber cord of end band (N) 50 2 20 5 12.5 20 27.5 35 20 Width of belt end rubber w2 (mm) 25 25 0 25 25 25 25 25 10 Angle θ1 of the first straight line (°) 3 3 3 3 3 3 3 3 3 Angle θ2 of the second straight line (°) 10 10 10 10 10 10 10 10 10 Distance d1 from the second outer end to the tread end (mm) 10 10 10 10 10 10 10 10 10 Distance d3 (mm) between the second end and the second outer end 20 20 20 20 20 20 20 20 20 Distance d4 (mm) between the outer end and the belt layer 0 1 0 1 1 1 0.6 0.2 1 Width of end band W1 (mm) 30 30 30 30 30 30 30 30 30 Total fineness of organic fiber cord (dtex) 4000 4000 4000 4000 4000 4000 4000 4000 4000 Density of organic fiber cords (pieces / 5cm) 40 40 40 40 40 40 40 40 40 Handling stability (index) 100 100 100 100 100 100 100 100 100 Durability (index) 100 100 105 110 120 130 120 110 115

[0091]

Table 2

[0092] Example 7 Example 8 Example 9 Example 10 Example 11 Example 12 Example 13 Example 14 Example 15 Constraint force of organic fiber cord of end band (N) 20 20 20 20 20 20 20 20 20 Width of belt end rubber w2 (mm) 20 40 50 25 25 25 25 25 25 Angle θ1 of the first straight line (°) 3 3 3 2 4 3 3 3 3 Angle θ2 of the second straight line (°) 10 10 10 10 10 5 30 40 10 Distance d1 from the second outer end to the tread end (mm) 10 10 10 10 10 10 10 10 0 Distance d3 (mm) between the second end and the second outer end 20 20 20 20 20 20 20 20 20 Distance d4 (mm) between the outer end and the belt layer 1 1 1 1 1 1 1 1 1 Width of end band w1 (mm) 30 30 30 30 30 30 30 30 30 Total fineness of organic fiber cord (dtex) 4000 4000 4000 4000 4000 4000 4000 4000 4000 Density of organic fiber cords (pieces / 5cm) 40 40 40 40 40 40 40 40 40 Handling stability (index) 100 99 98 100 98 100 100 100 100 Durability (index) 120 130 130 125 130 110 130 110 110

[0093]

Table 3

[0094] Example 16 Example 17 Example 18 Example 19 Example 20 Example 21 Example 22 Example 23 Example 24 Constraint force of organic fiber cord of end band (N) 20 20 20 20 20 20 20 20 20 Width of belt end rubber w2 (mm) 25 25 25 25 25 25 25 25 25 Angle θ1 of the first straight line (°) 3 3 3 3 3 3 3 3 3 Angle θ2 of the second straight line (°) 10 10 10 10 10 10 10 10 10 Distance d1 from the second outer end to the tread end (mm) 20 25 10 10 10 10 10 10 10 Distance d3 (mm) between the second end and the second outer end 20 20 5 10 30 45 20 20 20 Distance d4 (mm) between the outer end and the belt layer 1 1 1 1 1 1 0.2 2 1 Width of end band w1 (mm) 30 30 30 30 30 30 30 30 20 Total fineness of organic fiber cord (dtex) 4000 4000 4000 4000 4000 4000 4000 4000 4000 Density of organic fiber cords (pieces / 5cm) 40 40 40 40 40 40 40 40 40 Handling stability (index) 98 95 100 100 99 98 100 98 100 Durability (index) 135 130 115 120 130 130 110 120 120

[0095]

Table 4

[0096] Example 25 Example 26 Example 27 Example 28 Example 29 Example 30 Example 31 Example 32 Example 33 Constraint force of organic fiber cord of end band (N) 20 20 20 20 20 20 20 20 20 Width of belt end rubber w2 (mm) 25 25 25 25 25 25 25 25 25 Angle θ1 of the first straight line (°) 3 3 3 3 3 3 3 3 3 Angle θ2 of the second straight line (°) 10 10 10 10 10 10 10 10 10 Distance d1 (mm) between the second outer end and the tread end 10 10 10 10 10 10 10 10 10 Distance d3 (mm) between the second end and the second outer end 20 20 20 20 20 20 20 20 20 Distance d4 (mm) between the outer end and the belt layer 1 1 1 1 1 1 1 1 1 Width of end band w1 (mm) 40 50 30 30 30 30 30 30 30 Total fineness of organic fiber cord (dtex) 4000 4000 900 2000 4500 5500 4000 4000 4000 Density of organic fiber cords (pieces / 5cm) 40 40 40 40 40 40 30 50 60 Handling stability (index) 99 98 100 100 99 97 100 99 97 Durability (index) 130 130 115 120 131 133 120 131 133

[0097] The test results confirmed that the tires of the examples had a larger total value of steering stability and durability evaluation than the tires of the comparative examples, and that they were able to achieve a high and balanced balance between steering stability and durability during high-speed running.

Claims

1. A pneumatic tire, characterized in that: have: a carcass extending between the pair of bead portions so as to pass through the tread portion and the pair of sidewall portions; a belt layer composed of at least two belt cords arranged on the outer side of the carcass in the tire radial direction; a belt layer disposed on the outer side of the belt layer in the tire radial direction; and a belt end rubber disposed between the belt layer and the band layer so as to include a position of an outer end of the belt layer in the tire axial direction; The belt layer includes an end belt covering the outer end of the belt layer and at least one full belt. The end bands comprise organic fiber cords, The organic fiber cords of the end band have a restraining force of 5 to 35 N at a position outside the outer end of the belt layer in the tire radial direction. In a tire cross section including the tire rotation axis, the tread portion includes a pair of tread ends and a tread profile portion extending between the tread ends. In the tread profile portion, a first straight line connecting the center position in the tire axial direction and the tread end has an angle of 2° or more relative to the tire axial direction. The belt plies include a first belt ply and a second belt ply arranged on the outer side of the first belt ply in the tire radial direction. The outer end of the belt layer includes a first outer end of the first belt ply and a second outer end of the second belt ply, The second outer end is located axially outward from the tread end and axially inward from the first outer end. The distance between the second outer end and the tread end in the tire axial direction is 5 to 20 mm. The tread portion includes an outer contour portion extending from the tread end toward the outer side in the tire axial direction. In the outer contour portion, a second straight line connecting the tread end and the outer position of the second outer end in the tire radial direction has an angle of 10 to 30 degrees with respect to the first straight line. A belt end of the belt layer on the outer side in the tire axial direction is aligned with the first outer end.

2. The pneumatic tire according to claim 1, wherein: The belt end rubber extends from a position axially outward from the first outer end to a position axially inward from the second outer end.

3. The pneumatic tire according to claim 1 or 2, wherein: The width of the belt end rubber in the tire axial direction is 10 to 50 mm.

4. The pneumatic tire according to claim 1 or 2, wherein: The width of the end band in the tire axial direction is 20 to 50 mm.

5. The pneumatic tire according to claim 1 or 2, wherein: A distance between the outer end of the belt layer and the band layer in the tire radial direction is 0.2 to 2.0 mm.

6. The pneumatic tire according to claim 1 or 2, wherein: The total fineness of the organic fiber cord is 900 to 5500 dtex.

7. The pneumatic tire according to claim 1 or 2, wherein: The number of the organic fiber cords woven into each 5 cm ranges from 30 to 60.

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