JP2013095369A - Pneumatic tire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pneumatic tire capable of improving run flat durability while maintaining tire weight.SOLUTION: The pneumatic tire includes: a reinforcement rubber member provided at a tire width direction inner side of a carcass layer at a tire side, forming a crescent shaped cross section along the carcass layer, and having a JIS hardness (20°C) of 70-85 and a loss factor tanδ (60°C) of 0.10 or lower; and a side rubber member provided at a tire width direction outer side of the carcass layer at the tire side. At least a part of the side rubber member positioned at the tire radial direction inner side than the tire maximum width position includes rubber having physical properties so that the JIS hardness (20°C) is 70-85 and the loss factor tanδ (60°C) is 0.10 or lower.

Description

  The present invention relates to a pneumatic tire.

  A so-called side-reinforcing run-flat tire is known in which a reinforcing rubber member having a crescent cross section is provided on the side of the tire inner surface facing the tire cavity region of the sidewall portion. In this run-flat tire, in order to secure side rigidity during run-flat running (during abnormal running with reduced air pressure) and at the same time to suppress heat generation due to tire deformation, a rubber with high modulus and low heat build-up is added to the reinforcing rubber member. It is used. In recent years, spare flat tires have been eliminated to increase the trunk space of vehicles that have been stored as spare tires, to improve trunk space design, or to improve fuel economy by reducing vehicle weight. More and more tires are installed on vehicles as genuine tires. Run-flat tires are currently mounted mainly on high-end sedan-type passenger cars and high-performance sports model passenger cars, but it is desired to be mounted on SUVs (Sport Utility Vehicles) as genuine tires.

  SUVs (Sport Utility Vehicles) are heavier than high-end sedan-type passenger cars and high-performance sport model passenger cars, and tire sizes for SUV tires are generally high-end sedan-type passenger cars and high-performance sports cars. Compared to run-flat tires used in model passenger cars, the aspect ratio is high, and the tire cross-section height (height from the bottom contacting the rim of the tire bead to the position having the maximum circumference of the tread) is high. Has been. For this reason, when the conventional run flat tire is applied to the run flat tire for SUV, the crescent-shaped reinforcing rubber member becomes large, and as a result, the weight of the run flat tire is significantly increased.

For example, as a run-flat tire having a tire flatness ratio of 60 or more, a pneumatic tire having a significantly improved run-flat durability is known (Patent Document 1).
The pneumatic tire includes a carcass that is rubber-coated with a one-ply radial array cord that reinforces a pair of sidewall portions and a tread portion between bead cores embedded in a pair of bead portions, and a tread on an outer periphery of the carcass. A bead filler rubber extending from the bead core toward the end of the tread portion, and a reinforcing rubber layer having a substantially crescent-shaped cross section on the inner surface of the innermost carcass ply. In this pneumatic tire, at least one protective rubber sheet that is relatively soft between the bead filler rubber and the carcass ply surrounding the bead filler rubber and / or between the reinforcing rubber layer and the carcass ply adjacent to the reinforcing rubber layer. Is placed.

JP 2000-21323 A

  When the known pneumatic tire is applied to an SUV run-flat tire, the tire cross-section height is further increased to withstand the heavy load of the vehicle. Therefore, the crescent-shaped reinforcing rubber layer must be enlarged. This will lead to a significant increase in weight of the run-flat tire.

  Then, an object of this invention is to provide the pneumatic tire which can improve run flat durability, maintaining a tire weight.

One aspect of the present invention is a pneumatic tire,
The crescent cross-sectional shape provided along the carcass layer is formed on the inner side in the tire width direction of the carcass layer in the tire side portion, the JIS hardness (20 ° C) is 70 to 85, and the loss coefficient tan δ (60 ° C) is A reinforced rubber member having physical properties of 0.10 or less;
A side rubber member provided on the outer side in the tire width direction of the carcass layer of the tire side portion.
Among the side rubber members, at least a portion located inward in the tire radial direction from the tire maximum width position has a JIS hardness (20 ° C.) of 70 to 85 and a loss coefficient tan δ (60 ° C.) of 0.10 or less. Includes rubber with physical properties.

  The pneumatic tire having the above-described configuration can improve run-flat durability while maintaining the tire weight.

It is a half sectional view of one side of the tire center line CL regarding the pneumatic tire for SUV of this embodiment. FIG. 2 is a pattern development view of an example in which a part of the tread pattern of the tread portion of the tire shown in FIG. 1 is developed on a plane. It is a figure explaining arrangement | positioning of the rubber | gum which has the predetermined rubber | gum physical property used for the side rubber member of the tire of this embodiment.

  The pneumatic tire of this embodiment will be described. The pneumatic tire according to the embodiment described below can be applied to, for example, a passenger car tire defined in Chapter A of JATMA YEAR BOOK 2009 (Japan Automobile Tire Association Standard). In addition, the pneumatic tire of the present invention can be applied to a small truck tire defined in Chapter B or a truck and bus tire defined in Chapter C.

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

FIG. 1 is a half cross-sectional view of one side of a tire center line CL regarding an SUV pneumatic tire (hereinafter simply referred to as a tire) 10 according to the present embodiment.
The tire 10 includes a carcass ply material 12 (12a, 12b), a belt material 14 (14a, 14b), and a bead core 16 as skeleton materials, and a tread rubber member 18 around these skeleton materials, It mainly has a side rubber member 20, a bead filler rubber member 22, a rim cushion rubber member 24, a reinforcing rubber member 25, and an inner liner rubber member 26.
The reinforcing rubber member 25 is a crescent-shaped member, and the carcass ply material 12 and the inner liner rubber member on the side of the tire cavity region with respect to the carcass ply material 12 from the shoulder side of the tread portion to the bead portion. 26 so as to be sandwiched between them. The reinforcement rubber member 25 is made of a rubber material having a high modulus and a low heat generation property so that the side portion does not bend more than necessary during run-flat running and at the same time suppresses heat generation due to tire deformation. That is, the tire 10 is a run flat tire whose side portions are reinforced with the reinforcing rubber member 25.

The carcass ply material 12 is a member in which an organic fiber is covered with rubber and is formed in a toroidal shape by winding between a pair of annular bead cores 16 and has two layers of ply materials 12a and 12b. The ply material 12a is wound by the bead core 16 and extends to the upper portion of the side portion on the outer side in the tire radial direction from the tire maximum width position, and ends. The ply material 12b is wound by the bead core 16 from the tire maximum width position. Also, it ends at the lower part of the side part in the tire radial direction.
Two belt members 14 a and 14 b are provided on the outer side of the carcass ply material 12 in the tire radial direction. The belt members 14a and 14b are members in which rubber is coated on a steel cord inclined at a predetermined angle, for example, 20 to 30 degrees with respect to the tire circumferential direction, and the lower belt member 14a is compared to the upper belt member 14b. Wide in the tire width direction. The inclination directions of the steel cords of the two-layer belts 14a and 14b are opposite to each other. For this reason, belt material 14a, 14b serves as a crossing layer, and it suppresses expansion of carcass ply materials 12a, 12b by the filled air pressure. Although not shown, a belt cover material obtained by coating organic fibers with rubber may be provided outside the belt material 14 in the tire radial direction so as to reinforce the above-described function of the belt material 14.

  A tread rubber member 18 is provided on the outer side of the belt material 14 in the tire radial direction to form a tread portion. Further, a side rubber member 20 is connected to an end portion of the tread rubber member 18 to form a side portion. The side rubber member 20 is provided on the outer side in the tire width direction of the carcass layer 14 at the tire side portion. A rim cushion rubber member 24 is provided at the inner end in the tire radial direction of the side rubber member 20 and is in contact with a rim on which the tire 10 is mounted. The bead core 16 is sandwiched between the portion of the carcass ply material 12b before being wound around the bead core 16 and the portion of the carcass ply material 12b after being wound around the bead core 16 outside the bead core 16 in the tire radial direction. Thus, a bead filler rubber member 22 is provided. An inner liner rubber member 26 is provided on the inner surface of the tire 10 facing the tire cavity region filled with air surrounded by the tire 10 and the wheel.

  FIG. 2 is a pattern development view of an example in which a part of the tread pattern 30 of the tread portion of the tire 10 shown in FIG. 1 is developed on a plane.

As shown in FIG. 2, the tread pattern 30 is a point-symmetric pattern centered on one point on the tire center line CL.
Inner circumferential main grooves 32a and 32b and outer circumferential main grooves 34a and 34b each having a groove center at the same distance away from the tire center line CL in the tire width direction.

  Between the inner circumferential main groove 32a and the inner circumferential main groove 32b, lug grooves 40 connected to the inner circumferential main grooves 32a and 32b are provided in a direction inclined with respect to the tire circumferential direction, and a plurality of centers are provided. A land portion 36 is provided. Each of the center land portions 36 is provided with a lug groove 42 extending from the inner circumferential main grooves 32a and 32b and is closed in the vicinity of the tire center line CL. A sipe 43 further extends from the closed end and is connected to the inner circumferential main grooves 32b and 32a. Of the center land portions 36, the lug grooves 42 of the center land portions 36 adjacent to each other in the tire circumferential direction are directed from the inner circumferential main grooves 32a and 32b, which are different from each other, into the center land portion 36. Extend at almost the same inclination angle.

  A lug groove 44a connected to the inner circumferential main groove 32a and the outer circumferential main groove 34a is provided between the inner circumferential main groove 32a and the outer circumferential main groove 34a in a direction inclined with respect to the tire circumferential direction. A plurality of intermediate land portions 38a are provided. Between the inner circumferential main groove 32b and the outer circumferential main groove 34b, lug grooves 44b connected to the inner circumferential main groove 32b and the outer circumferential main groove 34b are provided in a direction inclined with respect to the tire circumferential direction. A plurality of intermediate land portions 38b are provided. The configuration of the intermediate land portion 38b provided between the inner circumferential main groove 32b and the outer circumferential main groove 34b is an intermediate land portion 38a provided between the inner circumferential main groove 32a and the outer circumferential main groove 34a. In the following description, the intermediate land portion 38a provided between the inner circumferential main groove 32a and the outer circumferential main groove 34a will be mainly described. The intermediate land portion 38b provided between the main groove 32b and the outer circumferential main groove 34b will be described in parentheses.

  Each of the intermediate land portions 38a (38b) is provided with lug grooves 46a (46b) extending from the inner circumferential main grooves 32a (32b) and the outer circumferential main grooves 34a (34b), and the intermediate land portions 38a (38b). Is closed near the center position in the tire width direction. A sipe 47a (47b) further extends from the closed end, and is connected to the outer circumferential main groove 34a (34b) and the inner circumferential main groove 32a (32b). Among the intermediate land portions 38a (38b), the lug grooves 44a (44b) of the intermediate land portions 38a (38b) adjacent in the tire circumferential direction are the inner circumferential main grooves 32a (32b) and the outer circumferential main grooves 34a (34b). ) From different circumferential main grooves into the intermediate land portion 38a (38b).

  A shoulder land portion is provided outside the outer circumferential main groove 34a in the tire width direction. A shoulder land portion is provided outside the outer circumferential main groove 34b in the tire width direction. Since the configuration of these shoulder land portions is the same except that they are arranged point-symmetrically, the shoulder land portion provided outside the outer circumferential main groove 34a in the tire width direction will be mainly described below. The shoulder land portion provided outside the outer circumferential main groove 34b in the tire width direction will be described in parentheses.

  The shoulder land portion is formed by being surrounded by a plurality of shoulder lug grooves 50a (50b), outer circumferential main grooves 34a, and pattern ends Ea (Eb) provided along the tire circumferential direction. The shoulder lug groove 50a (50b) has a groove depth that gradually decreases from the outer circumferential main groove 34a (34b) toward the pattern end Ea (Eb). The shoulder land portion is provided with a shoulder groove 52a (52b) that connects two shoulder lug grooves 50a (50b) adjacent in the tire circumferential direction. Further, a sipe 54a (54b) that extends from the outer circumferential main groove 34a (34b) toward the shoulder groove 52a (52b) but is bent on a dogleg that does not reach the shoulder groove 52a (52b). A sipe 56a (56b) that extends outward from the shoulder groove 52a (52b) in the tire width direction but closes without reaching the pattern end Ea (Eb) is provided.

  In such a tire 10, the reinforcing rubber member 25 has a rubber physical property having a JIS hardness (20 ° C.) of 70 to 85 and a loss coefficient tan δ (60 ° C.) of 0.10 or less. The JIS hardness (20 ° C.) specifically refers to the result of testing at 20 ° C. using JIS K 6253 durometer hardness tester type A. The loss factor tan δ (60 ° C.) is a condition of a frequency of 20 Hz, initial strain of 10%, dynamic strain of ± 2%, temperature of 60 ° C. using a JIS K 6934 viscoelastic spectrometer (for example, a spectrometer manufactured by Toyo Seiki Seisakusho). This is the result of the measurement.

The reason why the reinforcing rubber member 25 has such rubber physical properties is that the tire 10 has run-flat durability.
Further, at least a portion of the side rubber member 20 located inward in the tire radial direction from the tire maximum width position has a JIS hardness (20 ° C.) of 70 to 85 and a loss coefficient tan δ (60 ° C.) of 0.10. It has the following rubber properties. The tire maximum width position refers to a position having the tire maximum width in the tire width direction of the tire 10 when it is mounted on a normal rim and filled with a normal internal pressure. The regular rim refers to a “standard rim” defined in JATAMA, “Design Rim” defined in TRA, or “Measuring Rim” defined in ETRTO. The normal internal pressure means “maximum air pressure” defined by JATMA, the maximum value of “TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES” defined by TRA, or “INFLATION PRESSURES” defined by ETRTO.
The rubber physical property of the side rubber member 20 at least in the portion inward of the tire radial direction from the tire maximum width position is made equal to the rubber physical property of the reinforcing rubber member 25 at least inward of the tire radial direction from the tire maximum width position. This is because in the tire 10, the reinforcing rubber member 26 alone cannot have run-flat durability while maintaining the tire weight. That is, by making the rubber physical property of the side rubber member 20 equal to the rubber physical property of the reinforcing rubber member 25, run-flat durability can be ensured while maintaining the tire weight. The rubber properties of the side rubber member 20 of the tire 10 are higher in JIS hardness (20 ° C.) and lower in a loss coefficient tan δ (60 ° C.) than a normal tire that is not a run-flat tire.
If the JIS hardness (20 ° C.) is less than 70 in the portion located on the inner side in the tire radial direction of at least the tire maximum width position of the side rubber member 20, run flat running becomes difficult, that is, run flat durability is improved. If the JIS hardness (20 ° C.) is greater than 80, the spring characteristics of the tire become high, the vibration riding comfort performance decreases, and road noise increases. The loss coefficient tan δ (60 ° C.) is preferably as low as possible in terms of run flat durability, but the limit (upper limit) of the loss coefficient tan δ (60 ° C.) at which improvement in run flat durability is observed is 0.10.

Moreover, it is preferable that the rubber | gum of the part located inside a tire radial direction rather than the tire maximum width position among the side rubber members 20 of the tire 10 has a physical property whose 100% expansion modulus is 5.0-10.0 MPa. . The 100% elongation modulus refers to a measurement result of a modulus at 100% deformation when a tensile test is performed at room temperature on a rubber sample having a shape according to JIS K 6251 3 dumbbell.
In the side rubber member 20, the run flat durability is further improved by setting the 100% elongation modulus of the rubber in the portion located inward in the tire radial direction from the maximum tire width position to 5.0 to 10.0 MPa. .

Further, in the rubber of a portion of the side rubber member 20 that is located on the inner side in the tire radial direction from the position of the maximum tire width, it is preferable that the minimum thickness of the rubber is 2.0 to 8.0 mm. When the minimum thickness is less than 2.0 mm, the improvement in run-flat durability is small, and when it exceeds 8.0 mm, the tire weight increases, the vibration ride performance decreases, and road noise increases.
Furthermore, it is preferable that the rubber having the rubber physical properties of the side rubber member 20 extends outward in the tire radial direction to a range of 50 to 80% of the tire cross-section height H. As shown in FIG. 3, the tire cross-sectional height is a height H from a bottom portion contacting the rim R at the bead end of the tire 10 to a position having the maximum circumferential length of the tread portion when the tire is mounted on a regular rim. Therefore, the end portion of the rubber having the above-described rubber properties of the side rubber member 20 is 0.5 to 0.8 times the height H as measured from the bottom of the bead end in contact with the rim R toward the outer side in the tire radial direction. It is preferably located in the range of positions. Therefore, it is preferable that the rubber having the above-mentioned rubber physical properties of the side rubber member 20 is disposed in the hatched region shown in FIG. If the side rubber members 20 are all made of rubber having the above-mentioned rubber properties, vibration riding comfort performance is reduced and road noise is increased.

  Further, the aspect ratio of the tire 10 (ratio of the tire cross-section height to the maximum tire width) is preferably 60 or more from the viewpoint of effectively improving run-flat durability. When the flatness ratio is less than 60, the tire cross-section height is small, and the run-flat durability is ensured only by the reinforcing rubber member 25 without using the rubber having the rubber physical properties as in the present embodiment for the side rubber member 20. This is because the rubber properties of the side rubber member 20 do not have to be as described above.

〔Example〕
Hereinafter, in order to investigate the effect of the tire 10 of the present embodiment, tires changed to various specifications from the tire 10 shown in FIGS. The tire size of the prototype tire is 225 / 65RF17 102H.
In addition to this, tire weight was measured for run-flat durability, vibration riding comfort and road noise.
For the run flat durability, a run flat tire drum endurance test was performed using the run flat tire drum endurance test conditions described in ECE30. The rim size used was 17 x 6.5 J, the tire pressure was 0 atm, the running speed was 80 km / hour, the load on the tire was 65% of the maximum load capacity specified by JATMA or ETRTO, and the tire failed. I drove it until The evaluation was performed based on the distance traveled, and the conventional example was set as a standard (100) and expressed as an index. The higher the index, the higher the mileage.
As for vibration comfort and road noise, tires were mounted on four SUV wheels, and the vehicle was run at a running speed of 50 km / hour on the test course, and sensory evaluation was performed by the driver. The rim size of the rim used was 17 × 6.5 J, and the tire air pressure was a regular internal pressure specified by JATMA, and a load equivalent to two passengers was applied. The evaluation of the vibration riding comfort / road noise was a three-step evaluation of ○ (good), × (impossible), and Δ (possible) by sensory evaluation.
The tire weight was expressed as an index with the tire weight of the conventional example as a reference (100). The higher the index, the lighter the tire weight.

Table 1 below shows the specifications and evaluation results of Examples 1 to 6 and Comparative Examples 1 to 4.
Table 2 below shows the specifications and evaluation results of Examples 7 to 11, conventional examples, and comparative examples 5 and 6.
In addition, the rubber physical property of the side rubber member 20 demonstrated in the following Tables 1-4 says the physical property of the rubber used for the part located in a tire radial direction inner side from a tire maximum width position at least.
From the evaluation results of Examples 1 to 3 and Comparative Examples 1 and 2, and further from the evaluation results of Examples 4 to 6 and Comparative Examples 3 and 4, the JIS hardness (20 ° C.) is 70 to 85, and the loss coefficient tan δ JIS hardness (20 ° C.) is present at a portion located on the inner side in the tire radial direction of at least the tire maximum width position of the side rubber member 20 with respect to the reinforcing rubber member 25 having a rubber property of (60 ° C.) of 0.10 or less. By using rubber having a physical property of 70 to 85 and having a loss coefficient tan δ (60 ° C.) of 0.10 or less, the run-flat durability can be improved while maintaining the tire weight equal to that of the conventional example. I understand.
From the evaluation results of Examples 7 to 11, conventional examples, and comparative examples 5 and 6, reinforcement having rubber physical properties of JIS hardness (20 ° C.) of 70 to 85 and loss factor tan δ (60 ° C.) of 0.10 or less. The JIS hardness (20 ° C.) is 70 to 85 and the loss coefficient tan δ (60 ° C.) is 0 at a portion located on the inner side in the tire radial direction of at least the tire maximum width position of the side rubber member 20 with respect to the rubber member 25. It can be seen that Examples 7 to 11 using rubber having physical properties of 10 or less can improve run-flat durability while maintaining the tire weight equivalent to that of the conventional example.

Table 3 shows the specifications and evaluation results of Examples 12 to 19 and Comparative Examples 7 to 10.
In Examples 12 to 19 and Comparative Examples 7 to 10, the JIS hardness (20 ° C.) of the side rubber member 20 is fixed to 75, and the loss coefficient tan δ (60 ° C.) is changed. From the evaluation results of Examples 12 to 19 and Comparative Examples 7 to 10, rubber properties of the reinforced rubber member 25 having a JIS hardness (20 ° C.) of 70 to 85 and a loss coefficient tan δ (60 ° C.) of 0.10 or less. It can be seen that by setting the loss coefficient tan δ (60 ° C.) of the side rubber member 20 to 0.1 or less within the range, the run-flat durability can be improved while maintaining the tire weight equal to that of the conventional example. .

Table 4 shows the specifications and evaluation results of Examples 20-23.
In Table 4, when the JIS hardness (20 ° C.) of the reinforcing rubber member 25 and the side rubber member 20 is 70 to 85 and the loss coefficient tan δ (60 ° C.) is 0.10 or less, the 100% modulus of the side rubber member 20 is Various changes have been made. As shown in Examples 20 to 23, it can be seen that the run-flat durability is improved as the 100% modulus is increased. As shown in Examples 21 and 22, setting the 100% elongation modulus to 5.0 to 10.0 MPa is preferable in terms of improving the run-flat durability while maintaining the tire weight as in the conventional case. In Example 23 in which the 100% modulus exceeds 10.0 MPa, the run-flat durability is not improved even when the 100% modulus is increased, while the vibration ride quality and road noise are about “possible”. Accordingly, the 100% elongation modulus is preferably 5.0 to 10.0 MPa.

  As mentioned above, the effect of the tire 10 of this embodiment is clear.

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

10 SUV pneumatic tires 12, 12a, 12b Carcass ply materials 14, 14a, 14b Belt material 16 Bead core 18 Tread rubber member 20 Side rubber member 22 Bead filler rubber member 24 Rim cushion rubber member 25 Reinforced rubber member 26 Inner liner rubber member 30 Red patterns 32a, 32b Inner circumferential main grooves 34a, 34b Outer circumferential main grooves 36 Center land portions 38a, 38b Intermediate land portions 40, 42, 44a, 44b, 46a, 46b Lug grooves 43, 47a, 47b, 54a, 54b , 56a, 56b Sipe 50a, 50b Shoulder lug groove 52a, 52b Shoulder groove

Claims (5)

A pneumatic tire,
A crescent cross-sectional shape provided along the carcass layer in the tire width direction inward of the carcass layer in the tire side portion has a JIS hardness (20 ° C.) of 70 to 85, and a loss coefficient tan δ (60 ° C.). A reinforced rubber member having a physical property of 0.10 or less,
A side rubber member provided on the outer side in the tire width direction of the carcass layer of the tire side portion,
Among the side rubber members, at least a portion located inward in the tire radial direction from the tire maximum width position has a JIS hardness (20 ° C.) of 70 to 85 and a loss coefficient tan δ (60 ° C.) of 0.10 or less. A pneumatic tire comprising rubber having physical properties.   2. The air according to claim 1, wherein rubber in a portion of the side rubber member that is located inward in the tire radial direction from the tire maximum width position has a physical property that a 100% elongation modulus is 5.0 to 10.0 MPa. Enter tire.   The rubber | gum of the part located in the tire radial inside rather than a tire maximum width position among the said side rubber members WHEREIN: The minimum thickness of the said rubber is 2.0-8.0 mm, The Claim 1 or 2 Pneumatic tires.   Among the side rubber members, the rubber having physical properties of JIS hardness (20 ° C.) of 70 to 85 and loss factor tan δ (60 ° C.) of 0.10 or less is 50 to 80% of the tire cross-section height H. The pneumatic tire according to claim 1, which extends outward in the tire radial direction. The pneumatic tire according to any one of claims 1 to 4, wherein the tire flatness ratio is 60 or more.

Images