JP2014151739A - Pneumatic tire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pneumatic tire which secures rigidity by a bead reinforcement layer for not deteriorating stability, and has improved rolling resistance performance by reducing weight of a tire, and in addition, has improved load durability by securing a flex zone on a side wall part sufficiently.SOLUTION: A bead reinforcement layer is a wave-shaped plate having variation in a tire width direction. The bead reinforcement layer is arranged on a region from 10 mm inside of the tire width direction to 10 mm outside of the tire width direction to base upon a center line of the tire width direction on a hoist part of a carcass ply. The bead reinforcement layer further has a through-hole.

Description

  The present invention relates to a pneumatic tire including a bead reinforcement layer.

  Conventionally, a pneumatic tire provided with a bead reinforcement layer is known (for example, refer to patent documents 1). The technique disclosed in Patent Document 1 includes a bead reinforcement layer made of a cord concentrically arranged with a bead core, a longitudinal wave portion that is uneven in the radial direction of the spiral, and an unevenness in a direction perpendicular to the radial direction of the spiral. This is a technique formed so as to include a transverse wave portion.

JP 2004-58685 A

  In the technique disclosed in Patent Document 1, since the bead reinforcement layer is composed only of a cord, the rigidity at the location where the bead reinforcement layer is disposed is not sufficient. For this reason, in order to ensure steering stability performance, it is necessary to provide the bead reinforcing layer over a wide range in the tire radial direction.

  Further, in the technique disclosed in Patent Document 1, since it is necessary to provide a bead reinforcing layer over a wide range in the tire radial direction, it is unclear whether an excellent rolling resistance performance can be realized by increasing the weight of the tire.

  Furthermore, in the technique disclosed in Patent Document 1, the formation of a bead reinforcement layer over a wide range in the tire radial direction may not be able to sufficiently secure a flexible flex zone in the sidewall portion, so that excellent load durability performance is achieved. It is unclear whether can be realized.

  The present invention has been made in view of the above circumstances, and on the premise that steering stability performance is not deteriorated by securing rigidity using a bead reinforcement layer, the tire resistance is reduced and rolling resistance performance is improved. In addition, an object of the present invention is to provide a pneumatic tire that sufficiently secures a flex zone in a sidewall portion and improves load durability.

  In order to solve the above-described problems, a pneumatic tire according to the present invention includes a bead filler disposed on the outer side of the bead core in a tire radial direction and between a main body portion and a winding portion of a carcass ply, and an extension of the bead filler. And a bead reinforcing layer disposed along the direction of movement. The bead reinforcing layer is a wavy plate having an amplitude in the tire width direction. The bead reinforcement layer is disposed in a region from the inner side 10 [mm] in the tire width direction to the outer side 10 [mm] in the tire width direction with respect to the center line in the tire width direction of the upper part of the carcass ply. Yes. The bead reinforcing layer includes a through hole.

  In the pneumatic tire according to the present invention, a bead reinforcement layer, which is a corrugated plate, is disposed in a predetermined region in the tire width direction with respect to the center line in the tire width direction of the upper part of the carcass ply, and the bead reinforcement layer is It has a through hole. As a result, by ensuring the rigidity due to the presence of the bead reinforcement layer itself, the steering stability performance is prevented from being deteriorated, the rolling resistance performance is improved by reducing the tire weight, and the flex zone in the sidewall portion is sufficient. The load durability performance is improved by securing.

FIG. 1 is a tire meridian cross-sectional view showing a region from a bead portion to a sidewall portion of a pneumatic tire according to an embodiment of the present invention. FIG. 2 is a perspective view showing a bead reinforcement layer used in the embodiment of the present invention. FIG. 3 is a diagram showing an angle θ formed by the tire radial direction and the ridge line of the bead reinforcing layer used in the embodiment of the present invention. FIG. 4 is a partial perspective view of the bead reinforcement layer, showing an enlargement of the encircled portion shown in FIG. 2.

  Hereinafter, embodiments of the pneumatic tire according to the present invention (basic modes and additional modes 1 to 4 shown below) will be described in detail with reference to the drawings. Note that these embodiments do not limit the present invention. In addition, the constituent elements of the above embodiment include those that can be easily replaced by those skilled in the art, or those that are substantially the same. Furthermore, various forms included in the above-described embodiment can be arbitrarily combined within a range obvious to those skilled in the art.

[Basic form]
Below, the basic form is demonstrated about the pneumatic tire which concerns on this invention. In the following description, the tire radial direction means a direction orthogonal to the rotational axis of the pneumatic tire, the tire radial inner side is the side toward the rotational axis in the tire radial direction, and the tire radial outer side is in the tire radial direction. The side away from the rotation axis. The tire circumferential direction refers to a circumferential direction with the rotation axis as a central axis. Further, the tire width direction refers to a direction parallel to the rotation axis, the inner side in the tire width direction is the side toward the tire equator in the tire width direction, and the outer side in the tire width direction is away from the tire equator in the tire width direction. Say the side. The tire equator plane is a plane that is orthogonal to the rotational axis of the pneumatic tire and passes through the center of the tire width of the pneumatic tire.

  FIG. 1 is a tire meridian cross-sectional view showing a region from a bead portion to a sidewall portion of a pneumatic tire according to an embodiment of the present invention. That is, the region shown in the figure is a region including a bead portion 10 on one side in the tire width direction and a sidewall portion 20 extending outward from the bead portion 10 in the tire radial direction. The sidewall portion 20 further includes a sidewall portion on the other side in the tire width direction that sequentially extends from the tread portion to the inside in the tire radial direction via a tread portion (not shown) extending outward in the tire radial direction. It is connected to a bead part (neither is shown). That is, in the pneumatic tire 1 according to the embodiment of the present invention, a pair of sidewall portions and a pair of bead portions are continuously formed around the tread portion in the tire meridian cross-sectional view. And a pair of bead part, a pair of side wall part, and a tread part are continuously extended in the tire peripheral direction, respectively, and the pneumatic tire 1 has comprised the toroidal shape as a whole.

  A bead core 12 having a ring shape extending in the tire circumferential direction is disposed in the bead portion 10. The bead core 12 is formed, for example, by bundling a plurality of bead wires made of high carbon steel, and the tire meridional cross-sectional shape of the bead core 12 can be selected from various shapes such as a quadrangle, a hexagon, and a circle.

  Further, in the region from the bead portion 10 to the tread portion (not shown) via the sidewall portion 20, at least one carcass ply 14 with a reinforcing ply cord embedded therein, as shown in FIG. It is installed. The carcass ply 14 is wound around the bead core 12 from the inner side in the tire width direction toward the outer side in the vicinity of the innermost end (end portion) in the tire radial direction, and the upper winding portion 14b on the outer side in the tire width direction with respect to the main body portion 14a. Is formed. Thus, since the carcass ply 14 is disposed in close contact with the bead core 12 in the vicinity of the end portion, the carcass ply 14 is separated from the bead core 12 due to the bending of the sidewall portion 20 or the tire filling air pressure. The carcass ply 14 does not easily deviate from the bead core 12 even when force is applied.

  The ply cord that is a component of the carcass ply 14 may extend at any angle with respect to the circumferential direction of the tire. The material of the ply cord can be selected from various materials, for example, organic fiber such as aramid, polyethylene and nylon, glass fiber, steel, and materials having rigidity equivalent to these. Can do.

  Further, the bead portion 10 is provided with a reinforcing layer 16 in which a reinforcing cord is embedded. The reinforcing layer 16 is a layer for preventing the carcass ply 14 from being worn when the pneumatic tire 1 rubs against a rim flange (not shown) during load rolling. The reinforcing layer 16 is disposed in close contact with the outer side in the tire width direction of the carcass ply 14 so as to cover a part of the winding portion 14b of the carcass ply 14. Thus, since the reinforcing layer 16 is disposed in close contact with the carcass ply 14, it is possible to suppress shear strain and circumferential strain in the reinforcing layer 16, particularly in the close contact portion.

  The reinforcing cord of the reinforcing layer 16 may extend at any angle with respect to the circumferential direction of the tire. Various materials can be selected for the reinforcing cord. For example, organic fibers such as aramid, polyethylene and nylon, glass fiber, steel, and materials having the same rigidity can be selected. it can.

  In addition, in the region outside the bead core 12 in the tire radial direction and between the main body portion 14a and the winding portion 14b of the carcass ply 14, the fall of the bead portion 10 due to the bending of the sidewall portion 20 is suppressed. For this purpose, a bead filler 18 is provided. The bead filler 18 is formed of a material having a rubber hardness higher than that of the surrounding rubber member. The tire meridian cross-sectional shape of the bead filler 18 is a substantially triangular shape that gradually decreases in thickness toward the outer side in the tire radial direction. Thus, by making the bead filler 18 into a substantially triangular shape in the tire meridional section, the rigidity gradually decreases from the inner side to the outer side in the tire radial direction, and the occurrence of shear strain due to the rigidity step in this direction is suppressed. be able to.

  Under such a premise, in the present embodiment, a bead reinforcing layer 30 is disposed along the extending direction of the bead filler 18 as shown in FIG.

  FIG. 2 is a perspective view showing a bead reinforcement layer used in the embodiment of the present invention. The bead reinforcing layer 30 shown in the figure is equivalent to metal materials such as carbon steel, stainless steel and aluminum alloy, fiber reinforced plastics such as CFRP (Carbon Fiber Reinforced Plastics) and GFRP (Glass Fiber Reinforced Plastics), and these materials. It can form with the material which exhibits the rigidity of.

  As shown in FIG. 1, the bead reinforcing layer 30 is a plate that is wavy in a tire meridian cross-sectional view and has a thickness in the tire width direction. Moreover, the said wave shape of the bead reinforcement layer 30 is a shape which has an amplitude in a tire width direction, as shown in FIG. The wave in the wave shape can be a sine wave, a rectangular wave, a triangular wave, a sawtooth wave, or any combination thereof. Among these, in particular, when a sine wave as shown in FIG. 1 is used, shear strain and circumferential strain that may be generated locally in the bead reinforcement layer 30 can be minimized.

  Thus, by using the bead reinforcement layer 30 as a corrugated plate made of a metal material or the like, the bead reinforcement layer 30 is compared with the case where the bead reinforcement layer made only of the cord disclosed in Patent Document 1 is used. The rigidity of itself can be significantly increased in the same size region in the tire radial direction. For this reason, even if the tire radial direction dimension of the bead reinforcing layer 30 is made smaller than before, it is possible to ensure the same steering stability performance as the conventional one. Further, by reducing the size of the bead reinforcing layer 30 in the tire radial direction, a wide flex zone can be secured in the sidewall portion 20, and the load durability performance can be improved.

  Further, in the present embodiment, the bead reinforcing layer 30 is formed from the tire width direction inner side 10 [mm] to the tire width direction with reference to the tire width direction center line CCL of the winding portion 14b of the carcass ply 14 shown in FIG. It is arrange | positioned in the area | region to outer 10mm. In addition, although the arrangement | positioning area | region of the bead reinforcement layer 30 is as above-mentioned, this is restricted to the part which does not overlap with the winding part 14b of the carcass ply 14 by tire meridian sectional view. The bead reinforcement layer 30 is disposed in the bead filler 18 by setting the tire width direction arrangement region of the bead reinforcement layer 30 from the tire width direction inner side 10 [mm] to the tire width direction outer side with reference to the tire width direction center line. It is possible to embed, and to improve the steering stability performance significantly. Further, by setting the above region from the tire width direction outer side 10 [mm] to the tire width direction inner side with respect to the tire width direction center line, the side rubber positioned on the outer side in the tire width direction of the winding portion 14b of the carcass ply 14 The bead reinforcement layer 30 can be embedded therein, and the load durability performance and the steering stability performance can be improved.

  Furthermore, in the present embodiment, bead reinforcement layer 30 includes through holes 30a. Thereby, the weight of the tire can be reduced, and as a result, the rolling resistance performance can be improved. Further, due to the presence of the through hole 30a, the rubber constituting the bead filler 18 flows through the through hole 30a to the outside in the tire width direction at the time of vulcanization, and adhesion between the bead filler 18 and the rubber located on the outer side in the tire width direction is increased. Can be increased. And by this adhesive improvement, it can suppress that the carcass ply 14 follows the bead reinforcement layer 30 at the time of load rolling of the pneumatic tire 1, and becomes wavy.

  As described above, in this embodiment, the bead reinforcing layer 30 shown in FIG. 2 is arranged as shown in FIG. In other words, in the present embodiment, the bead reinforcing layer 30 is a corrugated plate, the position in the tire width direction is defined, and the through hole 30 a is provided in the bead reinforcing layer 30. As a result, the rigidity due to the presence of the bead reinforcing layer 30 itself is ensured to prevent the deterioration of the steering stability performance, the rolling resistance performance is improved by reducing the tire weight, and the flex zone in the sidewall portion is sufficient. The load endurance performance is improved by ensuring the safety.

  The pneumatic tire 1 according to the present embodiment has normal manufacturing processes, that is, a tire material mixing process, a tire material processing process, a green tire molding process, a vulcanization process, and an inspection process after vulcanization. It is obtained through

[Additional form]
Next, additional embodiments 1 to 4 that can be optionally implemented with respect to the basic embodiment of the pneumatic tire according to the present invention will be described.

(Additional form 1)
FIG. 3 is a diagram showing an angle θ formed by the tire radial direction and the ridge line of the bead reinforcing layer used in the embodiment of the present invention. The pneumatic tire 1 on the left side of the figure is shown in a tire meridional section, while the bead reinforcement layer 30 on the right side of the figure is shown in a perspective view. In the basic mode, on the plane parallel to the tire equatorial plane, the angle θ formed by the ridge line L of the bead reinforcing layer 30 with respect to the tire radial direction is not less than 45 [°] and not more than 135 [°] (additional) Form 1) is preferred.

  When the angle θ is 90 [°] (the extending direction of the ridge line L is the tire circumferential direction), the bead reinforcing layer 30 exerts its role as an elastic body to the maximum when the pneumatic tire 1 rolls under load. To do. As a result, the region from the bead portion 10 to the sidewall portion 20 is easily bent, and excellent load durability can be realized. For this reason, the load endurance performance can be improved by setting the angle θ to a range of 45 [°] or more and 135 [°] or less, which is an angle range relatively close to 90 [°]. In addition, by setting the angle θ to a range of 60 [°] or more and 120 [°] or less which is closer to 90 [°], the region from the bead portion 10 to the sidewall portion 20 becomes more easily bent, and the load Durability can be remarkably improved.

(Additional form 2)
In the basic form and the like (the basic form and the form in which the additional form 1 is added to the basic form), the ratio of the area of the through hole 30a in the surface area of the bead reinforcing layer 30 is 10% to 60%. Some (additional form 2) is preferred. Here, the surface area of the bead reinforcing layer 30 means the surface (either the front surface or the back surface) of the through hole 30a of the bead reinforcing layer 30 when the through hole 30a is not formed. The area of 30 thick portions is not included.

  By setting the ratio to 10 [%] or more, the tire weight can be reduced and the rolling resistance performance can be further improved. Further, by setting the ratio to 10% or more, the rubber constituting the bead filler 18 at the time of vulcanization can more easily flow to the outer side in the tire width direction through the through hole 30a, and the bead filler 18 and the outer side in the tire width direction. Adhesiveness with the located rubber can be further enhanced. Further, by further improving the adhesiveness, it is further suppressed that the carcass ply 14 follows the bead reinforcement layer 30 and becomes wavy when the pneumatic tire 1 rolls under load.

  Further, by setting the ratio to 60 [%] or less, the rigidity of the bead reinforcing layer 30 itself is kept high, and even if the tire radial direction dimension of the bead reinforcing layer 30 is smaller than the conventional one, it is equivalent to the conventional one. Sufficient handling stability can be ensured. Further, by further reducing the size of the bead reinforcing layer 30 in the tire radial direction, a wide flex zone can be secured in the sidewall portion 20, and the load durability performance can be further improved.

  In addition, the said effect can be show | played by a higher level each by making the said ratio into 20 [%] or more and 45 [%] or less.

  In the additional form 2, it is more preferable that the ratio of the area of the through hole 30a in the surface area of the bead reinforcement layer 30 is larger at both ends in the tire radial direction of the bead reinforcement layer 30 than in the tire radial center. . Here, both ends in the tire radial direction are regions in which the bead reinforcement layer 30 is located within 25% of the tire radial direction inner side (outer side) from the tire radial direction outermost (innermost) position of the bead reinforcement layer 30. Say. The tire radial direction central portion refers to a region other than the tire radial direction both ends in the tire radial direction arrangement region of the bead reinforcing layer 30.

  Thus, by making the ratio of the area of the through hole 30a occupying the surface area of the bead reinforcement layer 30 larger than the center part in the tire radial direction at both ends in the tire radial direction of the bead reinforcement layer 30, particularly in the tire radial direction. At both ends, the rubber constituting the bead filler 18 flows sufficiently to the outside in the tire width direction through the through holes 30a during vulcanization, and the adhesion between the bead filler 18 and the rubber located on the outer side in the tire width direction is extremely increased. be able to. And by this significant improvement in adhesion, it is possible to further suppress the carcass ply 14 from following the bead reinforcing layer 30 and becoming wavy during the load rolling of the pneumatic tire 1.

(Additional form 3)
FIG. 4 is a partial perspective view of the bead reinforcement layer, showing an enlargement of the encircled portion shown in FIG. 2. In the basic form or the like (the form in which at least one of the additional forms 1 and 2 is added to the basic form and the basic form), the curvature radius R of the bent portion of the bead reinforcing layer 30 is 0. As shown in FIG. It is preferably 5 [mm] or more and 5.0 [mm] or less (additional form 3). By setting the radius of curvature R to 0.5 [mm] or more, it is possible to further improve the load endurance performance by suppressing the generation of cracks with the bent portion as the starting point when the pneumatic tire 1 is loaded and rolled. . Further, by setting the radius of curvature R to 5.0 [mm] or less, the bead reinforcing layer 30 is prevented from having a shape close to a straight line in the tire radial direction. Stability performance can be further improved.

  In addition, by setting the curvature radius R to 3.0 [mm] or less, the operational effects relating to the steering stability performance can be achieved at a higher level.

(Additional form 4)
In a basic form or the like (a form obtained by adding at least one of the additional forms 1 to 3 to the basic form and the basic form), as shown in FIG. 4, the thickness T of the bead reinforcing layer 30 is 0.1 [mm]. It is preferably 2.0 mm or less (additional form 4). By setting the thickness T to 0.1 [mm] or more, the steering stability performance can be further improved by securing sufficient rigidity by the bead reinforcing layer 30. Further, by setting the thickness T to 2.0 [mm] or less, the rolling resistance performance can be further improved without excessively increasing the tire weight.

  In addition, when the thickness T is 0.5 [mm] or more and 1.5 [mm] or less, each of the above-described effects can be achieved at a higher level.

  Each of the pneumatic tires configured according to the present embodiment described above (the basic form and the form in which any of the additional forms 1 to 4 including the basic form is optionally added) is the bead reinforcement layer 30. Is a pneumatic tire in which the position in the tire width direction is defined and the bead reinforcing layer 30 is provided with a through hole 30a. Therefore, according to these pneumatic tires, the rigidity due to the presence of the bead reinforcement layer 30 itself is ensured to prevent the deterioration of the steering stability performance, and the rolling resistance performance is improved by reducing the tire weight. The load endurance performance is improved by sufficiently securing the flex zone in the sidewall portion.

Various conditions shown in Table 1 (type of bead reinforcement layer, angle θ (angle θ) formed by the ridge line of the bead reinforcement layer with respect to the tire radial direction on a plane parallel to the tire equatorial plane, and the number of through holes in the surface area of the bead reinforcement layer Area ratio (through-hole ratio), radius of curvature R (curvature radius R) of the bent portion of the bead reinforcement layer, thickness T (thickness T) of the bead reinforcement layer, and tire radial width of the bead reinforcement layer (tire radial width) )), Pneumatic tires of Conventional Examples 1 and 2 and Examples 1 to 5 were produced. In the “type of bead reinforcement layer” in Table 1, the code means that a bead reinforcement layer of the type disclosed in Patent Document 1 (consisting only of a cord) is used. In Table 1, “type of bead reinforcement layer”, the plate is a wavy plate having an amplitude in the tire width direction, and is based on the center line in the tire width direction of the upper part of the carcass ply. It means that it is a bead reinforcement layer of a type provided in the region from the tire width direction inner side 10 [mm] to the tire width direction outer side 10 [mm] and having a through hole.

  For the tires (test tires) of Conventional Examples 1 and 2 and Examples 1 to 5, the tire size is 235 / 40R18 91Y, and the tire weight is measured for all these test tires (Conventional Example 1 is 100). As well as steering stability performance, rolling resistance performance and load durability performance. These results are also shown in Table 1. In Table 1, the thickness T of Conventional Examples 1 and 2 is the total gauge of the cord and cord coat compound (reinforcing material) in the tire meridian cross-sectional view.

(Maneuvering stability)
Each test tire is assembled to a rim of 18 × 8.5J as a front wheel at an air pressure of 230 kPa, and as a rear wheel is assembled to a rim of 18 × 8.5J at an air pressure of 210 kPa, and these are attached to a sedan type vehicle having a displacement of 2000 CC. A sensory evaluation was performed by two panelists when the vehicle was mounted and traveled on a dry road surface at a speed of 120 km / h, and the average value was calculated. And based on this calculation result, the index evaluation which used the prior art example 1 as a reference | standard (100) was performed. This evaluation shows that the larger the index, the higher the steering stability performance.

(Rolling resistance performance)
Each test tire is assembled on a rim of 18 x 8.5 J at an air pressure of 210 kPa, applied with a load of 8.01 kN, traveled on a drum at a speed of 80 km / h, and energy at a unit travel distance when the tire rolls on the drum The rolling resistance value of the tire was calculated from the loss amount. Based on this calculation result, index evaluation was performed using Conventional Example 1 as a reference (100). This evaluation shows that the larger the index, the higher the rolling resistance performance.

(Load durability)
Each test tire was assembled on an 18 × 9.5 J rim at an air pressure of 330 kPa, a load of 4.25 kN was applied, and the vehicle was run on a drum at 81 km / h, and the running distance when a visually observable failure occurred was measured. . And based on this measurement result, the index evaluation which used the prior art example 1 as a reference | standard (100) was performed. This evaluation shows that the greater the index, the longer the travel distance, that is, the higher the load durability performance.

  According to Table 1, all of the pneumatic tires of Examples 1 to 5 belonging to the technical scope of the present invention (using a predetermined plate as a bead reinforcing layer) fall within the technical scope of the present invention. It can be seen that, with respect to the pneumatic tires of Conventional Examples 1 and 2 that do not belong, deterioration of steering stability performance is prevented, rolling resistance performance is improved, and load durability performance is improved.

  The present invention includes the following aspects.

(1) A bead filler disposed outside the bead core in the tire radial direction and disposed between the main body portion and the upper part of the carcass ply, and a bead reinforcing layer disposed along the extending direction of the bead filler. In the pneumatic tire provided, the bead reinforcement layer is a corrugated plate having an amplitude in the tire width direction, and the bead reinforcement layer is in the tire width direction with respect to the center line in the tire width direction of the upper part of the carcass ply. A pneumatic tire provided in a region from an inner side 10 [mm] to an outer side 10 [mm] in the tire width direction, wherein the bead reinforcing layer includes a through hole.

  (2) The angle θ formed by the ridge line of the bead reinforcing layer with respect to the tire radial direction on a plane parallel to the tire equatorial plane is 45 ° or more and 135 ° or less. Pneumatic tires.

  (3) The pneumatic tire according to (1) or (2), wherein a ratio of an area of the through hole to a surface area of the bead reinforcing layer is 10 [%] to 60 [%].

  (4) The air according to (3), wherein the ratio of the area of the through hole to the surface area of the bead reinforcement layer is larger than the tire radial center at both ends in the tire radial direction of the bead reinforcement layer. tire.

  (5) The pneumatic according to any one of (1) to (4), wherein a curvature radius of a bent portion of the bead reinforcing layer is 0.5 [mm] or more and 5.0 [mm] or less. tire.

(6) The pneumatic tire according to any one of (1) to (5), wherein the bead reinforcing layer has a thickness of 0.1 [mm] to 2.0 [mm].

DESCRIPTION OF SYMBOLS 1 Pneumatic tire 10 Bead part 12 Bead core 14 Carcass ply 14a Main part 14b Winding part 16 Reinforcement layer 18 Bead filler 20 Side wall part 30 Bead reinforcement layer 30a Through-hole CCL Tire width direction center line L ridgeline R of the carcass ply winding part 14b The radius of curvature of the bent portion of the bead reinforcing layer T The thickness of the bead reinforcing layer 30 The angle formed by the tire radial direction and the ridge line L of the bead reinforcing layer 30

Claims (6)

A pneumatic system comprising a bead filler disposed outside a bead core in a tire radial direction and disposed between a main body portion and a winding portion of a carcass ply, and a bead reinforcing layer disposed along an extending direction of the bead filler. In the tire,
The bead reinforcing layer is a wavy plate having an amplitude in the tire width direction,
The bead reinforcement layer is disposed in a region from the tire width direction inner side 10 [mm] to the tire width direction outer side 10 [mm] with reference to the tire width direction center line of the upper portion of the carcass ply,
The bead reinforcing layer is a pneumatic tire having a through hole.   2. The pneumatic tire according to claim 1, wherein an angle θ formed by a ridge line of the bead reinforcing layer with respect to a tire radial direction on a plane parallel to the tire equatorial plane is 45 ° or more and 135 ° or less. .   The pneumatic tire according to claim 1 or 2, wherein a ratio of an area of the through hole to a surface area of the bead reinforcing layer is 10% to 60%.   4. The pneumatic tire according to claim 3, wherein a ratio of an area of the through hole to a surface area of the bead reinforcing layer is larger at both ends of the bead reinforcing layer in the tire radial direction than at a center portion in the tire radial direction.   The pneumatic tire according to any one of claims 1 to 4, wherein a radius of curvature of a bent portion of the bead reinforcing layer is 0.5 [mm] or more and 5.0 [mm] or less.   The pneumatic tire according to any one of claims 1 to 5, wherein a thickness of the bead reinforcing layer is 0.1 [mm] or more and 2.0 [mm] or less.

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