Pneumatic tire

Abstract

The pneumatic tire according to the invention comprises: a plurality of sipes extending obliquely relative to the tire width direction are arranged in the land portion; when adjacent sipes in the tire circumferential direction protrude in the tire width direction, at least a portion thereof overlaps in the tire circumferential direction or is not spaced in the tire circumferential direction; and the number distribution of sipes is largest for the medium sipes among the large sipes, medium sipes and small sipes.

Description

Technical Field

[0001] This disclosure relates to an inflatable tire. Background Technology

[0002] Typically, it has been proposed to arrange sipes at intervals in the ribbed land section in the tire circumferential direction, with each sipe extending obliquely relative to the tire width direction (e.g., Patent Document 1). According to this configuration, it can be said that operating noise can be reduced.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Publication No. 2016-540675 Summary of the Invention

[0006] The problem the invention aims to solve

[0007] However, when a pitch variation is applied while arranging the sipes as described above, the circumferential length of the tread blocks separated by the sipes in the tire circumferential direction varies more significantly in the tire width direction. As a result, the tread blocks may exhibit uneven wear patterns, raising concerns about potential degradation in the tread blocks' resistance to uneven wear and, consequently, the tire's resistance to uneven wear.

[0008] Therefore, the purpose of this disclosure is to provide a pneumatic tire that can improve noise performance while suppressing the degradation of resistance to uneven wear.

[0009] Solution for solving the problem

[0010] The main structure of this disclosure is as follows.

[0011] (1) A pneumatic tire, comprising:

[0012] At least two circumferential grooves extending along the tire circumferential direction on the tread surface;

[0013] The ribbed landmass is confined between the circumferential grooves;

[0014] Multiple sipes are arranged in the land section, each sipe extending at an angle relative to the width of the tire;

[0015] When projected onto the tire width direction, adjacent sipes in the tire circumferential direction at least partially overlap in the tire circumferential direction, or have no spacing in the tire circumferential direction.

[0016] The sipes consist of three types: a large sipe with the maximum tilt angle relative to the tire width direction, a small sipe with the minimum tilt angle relative to the tire width direction, and a medium sipe with an intermediate tilt angle relative to the tire width direction between the large and small sipes.

[0017] Furthermore, among the large, medium, and small cutter grooves, the medium cutter groove has the largest number of grooves.

[0018] Here, "tread surface" refers to the surface of the tire that contacts the road surface in the entire circumferential direction when the pneumatic tire is mounted on an applicable rim, inflated to the specified internal pressure, and subjected to the maximum load.

[0019] In addition, the “groove” in “circumferential groove” refers to a groove with an opening width of 1 mm or more in the reference state, wherein the tire is mounted on the applicable rim, inflated to the specified internal pressure, and unloaded (hereinafter referred to as the “reference state”).

[0020] In addition, "sipes" refers to sipes with a sipe width such that when a pneumatic tire is mounted on an applicable rim, inflated to a specified internal pressure, and subjected to maximum load, a portion of the sipe wall is closed.

[0021] Furthermore, "no spacing in the tire circumferential direction" is intended to include cases where, taking into account manufacturing tolerances, the spacing in the tire circumferential direction is 5% or less of the sipe pitch length.

[0022] In this specification, "applicable rim" refers to an applicable rim of an applicable size that is already described or will be described in the industry standards in effect in the region where the tire is manufactured and used (such as the JATMA Yearbook of the Japan Automobile Tire Manufacturers Association (JATMA) in Japan, the standards manual of the European Tire and Rim Technology Organization (ETRTO) in Europe, and the Yearbook of the Tire and Rim Association (TRA) in the United States; i.e., in addition to the current size, the aforementioned "rim" also includes sizes that may be included in the aforementioned industry standards in the future. As an example of "sizes to be described in the future," sizes described as "FUTURE DEVELOPMENTS" in the 2013 edition of ETRTO can be cited). However, in the case of a size not described in the aforementioned industry standards, it refers to a rim having a width corresponding to the width of the tire's bead.

[0023] In addition, "specified internal pressure" refers to the air pressure (maximum air pressure) corresponding to the maximum load capacity of a single tire for the applicable size and ply rating described in JATMA, etc., and in the case of a size not described in the aforementioned industry standard, "specified internal pressure" refers to the air pressure (maximum air pressure) corresponding to the maximum load capacity specified for each vehicle on which the tire is mounted.

[0024] Furthermore, the “maximum load” described later refers to the load corresponding to the aforementioned maximum load capacity.

[0025] The effects of the invention

[0026] According to this disclosure, a pneumatic tire that can improve noise performance while suppressing the degradation of resistance to uneven wear can be provided. Attached Figure Description

[0027] Figure 1 This is a development view showing a portion of the tread surface of a pneumatic tire according to one embodiment of the present disclosure.

[0028] Figure 2 This is a diagram depicting an example configuration of a communication device.

[0029] Figure 3 This is a diagram depicting an example configuration of a communication device. Detailed Implementation

[0030] In the following, embodiments of the present disclosure will be illustrated and described in detail with reference to the accompanying drawings. The internal structure of a pneumatic tire (hereinafter also simply referred to as a "tire") can be constructed similarly to that of a conventional tire, and therefore its detailed description will be omitted. As an example, a tire may be provided with a pair of bead portions, a pair of sidewall portions extending between the pair of bead portions, and a tread portion extending between the sidewall portions. The tire may also include a carcass extending circumferentially between the pair of bead portions, and a belt disposed radially outward of the crown portion of the carcass. In the following, dimensions, etc., refer to the dimensions under the above-described standard condition.

[0031] Figure 1 This is a developed view showing a portion of the tread surface of a pneumatic tire according to one embodiment of the present disclosure. Figure 1 As shown, the tire has two or more (two in the range shown) circumferential grooves 2 (2a, 2b) extending in the circumferential direction on the tread surface 1.

[0032] In the example shown, the circumferential grooves 2 extend without tilting in the tire circumferential direction, but they may also extend at a tilt angle of 5° or less relative to the tire circumferential direction. Furthermore, in the example shown, the circumferential grooves 2 extend linearly, but they may also extend in a zigzag or curved shape. The groove width (opening width) of the circumferential grooves 2 is not particularly limited, but can be, for example, from 3 mm to 15 mm. The groove depth (maximum depth) of the circumferential grooves 2 is also not particularly limited, but can be, for example, from 4 mm to 10 mm.

[0033] The ribbed land portion 3 is defined between the circumferential grooves 2. That is, the land portion 3 is not completely separated by the width direction groove in the tire circumferential direction.

[0034] Multiple sipes 4, 5 and 6 are arranged in the land section 3, each sipe extending obliquely relative to the width direction of the tire.

[0035] Slots 4, 5, and 6 can be flat slots. Slots 4, 5, and 6 can extend linearly in a planar view or extend in a zigzag pattern. Slots 4, 5, and 6 can also be three-dimensional slots, wherein the slot wall surface forms an uneven shape along the depth direction. Three-dimensional slots can extend, for example, by bending along the depth direction or by extending in a wavy shape along the depth direction.

[0036] There are no particular restrictions on the width (opening width) of the grooves 4, 5 and 6, but it can be, for example, from 0.1 mm to 2 mm. There are also no particular restrictions on the groove depth (maximum depth) of the grooves 4, 5 and 6, but it can be, for example, from 0.1 mm to 10 mm.

[0037] The adjacent sipes 4, 5, and 6 in the tire circumferential direction are configured such that when projected onto the tire width direction, at least a portion of them overlap in the tire circumferential direction, or there is no spacing in the tire circumferential direction. Therefore, the sipes 4, 5, and 6 are densely arranged in the tire circumferential direction.

[0038] Sipes 4, 5, and 6 are composed of three types: a large sipe 4 with the maximum tilt angle relative to the tire width direction, a small sipe 5 with the minimum tilt angle relative to the tire width direction, and a medium sipe 6 with an intermediate tilt angle relative to the tire width direction between the large sipe 4 and the small sipe 5.

[0039] The angle of inclination of the large sipe 4 relative to the tire width direction is greater than the angle of inclination of the middle sipe 6 and the small sipe 5 relative to the tire width direction, and there are no particular restrictions, but it can be any value in the range of, for example, 12° to 83°.

[0040] The inclination angle of the center sipe 6 relative to the tire width direction is within the range of the intermediate inclination angle between the inclination angle of the large sipe 4 relative to the tire width direction and the inclination angle of the small sipe 5 relative to the tire width direction, and is not particularly limited, but can be any value in the range of, for example, 10° to 81°.

[0041] The inclination angle of the small sipe 5 relative to the tire width direction is smaller than that of the large sipe 4 and the middle sipe 6 relative to the tire width direction, and there are no particular restrictions, but it can be any value in the range of, for example, 8° to 79°.

[0042] Regarding the distribution of the number of sipes 4, 5, and 6, among the large sipe 4, medium sipe 6, and small sipe 5, the medium sipe 6 has the largest number. That is, in the entire circumferential direction of the tire, the number of medium sipes 6 is greater than the number of large sipes 4 and small sipes 5.

[0043] The number of medium-sized cutting grooves 6 relative to the total number of cutting grooves (the sum of the number of large cutting grooves 4, medium-sized cutting grooves 6 and small cutting grooves 5) is preferably 33.4% to 60%, more preferably 37% to 50%.

[0044] In this embodiment, among the distribution of the number of adjacent sipes in the tire circumferential direction, the number of adjacent large sipes 4 and small sipes 5 in the tire circumferential direction is the smallest. That is, among the pairs of adjacent sipes in the tire circumferential direction, the number of pairs of large sipes 4 and small sipes 5 is the smallest (smaller than the number of pairs of large sipes 4, pairs of medium sipes 6, pairs of small sipes 5, pairs of large sipes 4 and medium sipes 6, and pairs of medium sipes 6 and small sipes 5).

[0045] Furthermore, in this embodiment, among the distribution of the number of adjacent sipes in the tire circumferential direction, the number of adjacent sipes 6 in the tire circumferential direction is the largest. That is, among the pairs of adjacent sipes in the tire circumferential direction, the number of pairs of middle sipes 6 is the largest (larger than the number of pairs of large sipes 4, pairs of small sipes 5, pairs of large sipes 4 and middle sipes 6, pairs of large sipes 4 and small sipes 5, and pairs of middle sipes 6 and small sipes 5).

[0046] The operational effects of the pneumatic tire of this embodiment will be described below.

[0047] In the pneumatic tire of this embodiment, firstly, a plurality of sipes 4, 5, and 6 are arranged in the land portion 3, each sipe extending obliquely relative to the tire width direction, and adjacent sipes 4, 5, and 6 in the tire circumferential direction are configured such that when projected onto the tire width direction, at least a portion of them overlap in the tire circumferential direction, or there is no gap in the tire circumferential direction. As a result, the tire's noise reduction performance can be improved.

[0048] Furthermore, in the pneumatic tire of this embodiment, regarding the distribution of the number of sipes 4, 5, and 6, the number of medium sipes 6 is the largest among the large sipes 4, medium sipes 6, and small sipes 5. Therefore, the variation in the tire's circumferential length of the tread blocks defined between the sipes in the tire width direction can be suppressed, thereby suppressing the reduction in the resistance to uneven wear of the tread blocks, and thus suppressing the reduction in the tire's resistance to uneven wear.

[0049] As described above, the pneumatic tire according to this embodiment can improve noise reduction performance while suppressing the reduction in resistance to uneven wear.

[0050] Preferably, in the distribution of the number of adjacent sipes 4, 5, and 6 in the tire circumferential direction, the number of adjacent large sipes 4 and small sipes 6 is minimized. This is because the variation in the tire width direction of the tire circumferential length of the tread blocks defined between the sipes can be further suppressed, thereby further suppressing the reduction in the resistance to uneven wear of the tread blocks, and thus further suppressing the reduction in the tire's resistance to uneven wear.

[0051] Preferably, in the distribution of the number of adjacent sipes 4, 5, and 6 in the tire circumferential direction, the central sipe 6 has the largest number of adjacent sipes in the tire circumferential direction. This is because it can further suppress the variation of the tire circumferential length of the tread blocks defined between the sipes in the tire width direction, thereby further suppressing the reduction in the resistance to uneven wear of the tread blocks, and thus further suppressing the reduction in the tire's resistance to uneven wear.

[0052] Preferably, the number of center sipes 6 is 33.4% to 60% of the total number of sipes. Setting it to 34% or more can more effectively suppress the reduction in tire wear resistance due to uneven wear, and conversely, setting it to 50% or less can more effectively improve noise reduction performance. For the same reason, it is preferable that the number of center sipes 6 is 37% to 50% of the total number of sipes.

[0053] [Example Configuration of Communication Device]

[0054] Figure 2 and Figure 3This diagram illustrates an example configuration of a communication device. The tire may be equipped with an RF tag serving as communication device 100, 200. The RF tag includes an IC chip and an antenna. The RF tag may be arranged, for example, sandwiched between multiple components of the same or different types constituting the tire. Doing so makes it easier to attach the RF tag during tire production and improves the productivity of tires equipped with RF tags. In this example, the RF tag may be arranged, for example, sandwiched between the bead filler and another component adjacent to the bead filler. The RF tag may also be embedded within any component constituting the tire. Doing so reduces the load applied to the RF tag compared to arranging it between multiple components constituting the tire. As a result, the durability of the RF tag can be improved. In this example, the RF tag may be embedded, for example, in a rubber component such as the tread rubber or sidewall rubber. Preferably, in the circumferential direction (i.e., along the outer surface of the tire in a cross-sectional view in the tire width direction), the RF tag is not arranged at the boundary between components with different rigidities. By doing so, the RF tag is not arranged at locations where strain is easily concentrated due to rigidity differences. Therefore, the load applied to the RF tag can be reduced. As a result, the durability of the RF tag can be improved. In this example, the RF tag is preferably not positioned at the boundary between the end of the tire carcass in a cross-sectional view along the tire width direction and the adjacent component (such as the sidewall rubber). There is no particular limitation on the number of RF tags. The tire may have only one RF tag, or it may have two or more RF tags. Here, the RF tag is illustrated and described as an example of a communication device, but different communication devices may also be used.

[0055] The RF tag can be, for example, positioned within the tread of the tire. By doing so, the RF tag will not be damaged by tire sidecuts. The RF tag can also be, for example, positioned in the center of the tread in the tire width direction. The center of the tread is a location where deflection is less likely to concentrate. This reduces the load applied to the RF tag, thereby improving its durability. Furthermore, it can suppress differences in communication performance between the two outer edges of the tire and the RF tag in the tire width direction. In this example, the RF tag can be, for example, positioned within half the tread width centered on the tire's equatorial plane in the tire width direction. The RF tag can also be, for example, positioned at the tread end in the tire width direction. When the location of the reader communicating with the RF tag is predetermined, the RF tag can be, for example, positioned at the tread end closer to the reader. In this example, the RF tag can be, for example, positioned within one-quarter of the tread width in the tire width direction with the tread end as the outer edge.

[0056] The RF tag can be positioned, for example, on the inner side of the tire cavity relative to the tire carcass, which includes one or more carcass plies spanning between the bead portions. By doing so, the RF tag is less likely to be damaged by impacts, sidecuts, or punctures from outside the tire. As an example, the RF tag can be positioned in close contact with the inner surface of the tire carcass. As another example, when another component is present on the inner side of the tire cavity relative to the tire carcass, the RF tag can be positioned, for example, between the tire carcass and another component located on the inner side of the tire cavity relative to the tire carcass. An example of another component located on the inner side of the tire cavity relative to the tire carcass could be the inner liner forming the inner surface of the tire. As another example, the RF tag can be attached to the inner surface of the tire facing the tire cavity. By configuring the RF tag to be attached to the inner surface of the tire, the attachment of the RF tag to the tire and the inspection or replacement of the RF tag can be easily performed. That is, the attachability and maintainability of the RF tag can be improved. Furthermore, by attaching the RF tag to the inner surface of the tire, compared to a configuration where the RF tag is embedded in the tire, the RF tag is prevented from becoming the source of tire failure. In addition, when the carcass comprises multiple carcass plies and there are locations where multiple carcass plies are stacked, RF tags can be placed between the stacked carcass plies.

[0057] An RF tag can be arranged, for example, in the tread of a tire relative to a belt comprising one or more belt plies, radially outward of the tire. As an example, the RF tag can be arranged to be in close contact with the belt radially outward of the tire relative to the belt. As another example, when a reinforcing belt layer is provided, the RF tag can be arranged to be in close contact with the reinforcing belt layer radially outward of the tire relative to the reinforcing belt layer. As yet another example, the RF tag can be embedded in the tread rubber radially outward of the tire relative to the belt in the tread of the tire. By arranging the RF tag radially outward of the tire tread relative to the belt, communication with the RF tag from the outside of the tire in the radial direction is less likely to be obstructed by the belt. Therefore, communication performance with the RF tag from the outside of the tire in the radial direction can be improved. Furthermore, the RF tag can be arranged radially inward of the tire tread relative to the belt, for example. By doing so, the radially outward side of the RF tag is covered by the belt, so the RF tag is less likely to be damaged by impacts or punctures from the tread surface. As an example, an RF tag can be positioned in the tire tread between the belt and the tire carcass located radially inward relative to the belt. Furthermore, when the belt comprises multiple belt plies, the RF tag can be positioned in the tire tread between any two belt plies. By doing so, the radially outer side of the RF tag is covered by one or more belt plies, making the RF tag less likely to be damaged by impacts or punctures from the tread surface.

[0058] In the case of truck or bus tires, the RF tag can be arranged, for example, between the cushioning rubber and the tread rubber, or between the cushioning rubber and the sidewall rubber. By doing so, the impact on the RF tag is mitigated by the cushioning rubber, thus improving the durability of the RF tag. The RF tag can also be embedded in the cushioning rubber. Furthermore, the cushioning rubber can be composed of multiple adjacent rubber components of the same or different types. In this case, the RF tag can be arranged between the multiple rubber components constituting the cushioning rubber.

[0059] RF tags can be positioned, for example, on the sidewall or bead portion of the tire. Alternatively, the RF tag can be positioned, for example, closer to a reader capable of communicating with the RF tag on one side of the sidewall or bead portion. This enhances communication performance between the RF tag and the reader. As an example, the RF tag can be positioned between the tire carcass and sidewall rubber, or between the tread rubber and sidewall rubber. The RF tag can be positioned, for example, in the radial direction of the tire between the tire's maximum width and the tread surface. This enhances communication performance with the RF tag from the outside of the tire in the radial direction compared to a configuration where the RF tag is positioned radially inside the tire relative to its maximum width. The RF tag can be positioned, for example, radially inside the tire relative to its maximum width. This positions the RF tag near the bead portion, which has high rigidity. Therefore, the load applied to the RF tag can be reduced. Consequently, the durability of the RF tag can be improved. As an example, the RF tag can be positioned adjacent to the bead core in the radial or width direction of the tire. Strain concentration is less likely near the bead core. Therefore, the load applied to the RF tag can be reduced. As a result, the durability of the RF tag can be improved. In particular, it is preferable that the RF tag is arranged radially inside the tire at a position relative to the tire's maximum width, and radially outside the tire relative to the bead core of the bead portion. By doing so, the durability of the RF tag can be improved, and communication between the RF tag and the reader is less likely to be obstructed by the bead core, thereby enhancing the communication performance of the RF tag. Furthermore, when the sidewall rubber is composed of multiple identical or different types of rubber components adjacent in the tire's radial direction, the RF tag can be arranged to be sandwiched between the multiple rubber components constituting the sidewall rubber.

[0060] In the case of tires used in passenger cars, the RF tag can be arranged between the bead filler and a component adjacent to the bead filler. By doing so, the RF tag can be positioned where strain concentration is unlikely due to the configuration of the bead filler. Therefore, the load applied to the RF tag can be reduced. As a result, the durability of the RF tag can be improved. The RF tag can, for example, be arranged between the bead filler and the tire carcass. The portion of the tire carcass holding the RF tag together with the bead filler can be located outside the tire width direction relative to the bead filler, or it can be located inside the tire width direction. When the portion of the tire carcass holding the RF tag together with the bead filler is located outside the tire width direction relative to the bead filler, the load applied to the RF tag due to impacts or damage from outside the tire in the tire width direction can be further reduced. As a result, the durability of the RF tag can be further improved. Furthermore, the bead filler may include a portion arranged adjacent to the sidewall rubber. In this case, the RF tag can be arranged between the bead filler and the sidewall rubber. Furthermore, the bead filler may include a portion arranged adjacent to the rubber bead wrapping. In this case, the RF tag can be arranged between the bead filler and the rubber bead wrapping.

[0061] In the case of tires used in trucks or buses, the RF tag can be arranged between a reinforcement and a member adjacent to the reinforcement. By doing so, the RF tag can be positioned where strain concentration is unlikely due to the configuration of the reinforcement. Therefore, the load applied to the RF tag can be reduced. As a result, the durability of the RF tag can be improved. The RF tag can be arranged, for example, between the reinforcement and the sidewall rubber. Furthermore, the RF tag can be arranged, for example, between the reinforcement and the tire carcass. The portion of the tire carcass that holds the RF tag together with the reinforcement can be located outside the tire width direction relative to the reinforcement, or it can be located inside the tire width direction. When the portion of the tire carcass that holds the RF tag together with the reinforcement is located outside the tire width direction relative to the reinforcement, the load applied to the RF tag due to external impacts or damage from the tire in the tire width direction can be further reduced. As a result, the durability of the RF tag can be further improved. The reinforcement may include a portion arranged adjacent to the rubber bead wrap. In this case, the RF tag can be arranged between the reinforcement and the rubber bead wrap. The reinforcement may include a portion arranged adjacent to the cap-shaped rubber on the outside of the tire width direction. In this configuration, the RF tag can be arranged between a reinforcement and a cap-shaped rubber layer. The reinforcement can be composed of multiple rubber components with different hardnesses. The RF tag can then be arranged between these rubber components. Alternatively, it can be sandwiched between the cap-shaped rubber layer and adjacent components. For example, the RF tag can be arranged between the cap-shaped rubber layer and the tire carcass ply. By doing so, the impact on the RF tag can be mitigated by the cap-shaped rubber layer. Therefore, the durability of the RF tag can be improved.

[0062] The RF tag can be arranged, for example, sandwiched between the rubber bead wrap and the sidewall rubber. By doing so, the RF tag can be positioned where strain is less likely to concentrate due to the configuration of the rubber bead wrap. Therefore, the load applied to the RF tag can be reduced. As a result, the durability of the RF tag can be improved. The RF tag can also be arranged, for example, sandwiched between the rubber bead wrap and the tire carcass. By doing so, the load applied to the RF tag due to impacts or damage from the rim can be reduced. Therefore, the durability of the RF tag can be improved.

[0063] In the case of tires used on trucks or buses, the RF tag can be arranged between a nylon bead wrap and another component adjacent to the nylon bead wrap on the outer or inner side in the tire width direction. By doing so, the position of the RF tag becomes less likely to fluctuate during tire deformation. Therefore, the load applied to the RF tag during tire deformation can be reduced. As a result, the durability of the RF tag can be improved. The nylon bead wrap can, for example, include a portion arranged adjacent to a rubber bead wrap on the outer side in the tire width direction. In this case, the RF tag can be arranged between the nylon bead wrap and the rubber bead wrap. The nylon bead wrap can, for example, include a portion arranged adjacent to the sidewall rubber on the outer side in the tire width direction. In this case, the RF tag can be arranged between the nylon bead wrap and the sidewall rubber. The nylon bead wrap can, for example, include a portion arranged adjacent to a reinforcement on the inner side in the tire width direction. In this case, the RF tag can be arranged between the nylon bead wrap and the reinforcement. Furthermore, the nylon bead wrap can, for example, include a portion arranged adjacent to a cap-shaped rubber on the inner side in the tire width direction. In this configuration, the RF tag can be arranged between the nylon bead wrap and the cap-shaped rubber. Furthermore, the nylon bead wrap may include, for example, a portion arranged adjacent to the tire carcass on the inner side in the tire width direction. In this configuration, the RF tag can be arranged between the nylon bead wrap and the tire carcass. Furthermore, the nylon bead wrap may include, for example, a portion arranged adjacent to the steel wire bead wrap on the inner side in the tire width direction. In this configuration, the RF tag can be arranged between the nylon bead wrap and the steel wire bead wrap. As described above, the RF tag can be arranged between the nylon bead wrap and another member adjacent to the nylon bead wrap on the outer or inner side in the tire width direction. Specifically, by covering the outer side of the RF tag in the tire width direction with the nylon bead wrap, the load applied to the RF tag due to external impacts or damage from the tire in the tire width direction can be further reduced. Therefore, the durability of the RF tag can be further improved.

[0064] The RF tag can be arranged between the bead wrapping and another component adjacent to the bead wrapping on the inner or outer side in the tire width direction. By doing so, the position of the RF tag becomes less likely to fluctuate during tire deformation. Therefore, the load applied to the RF tag during tire deformation can be reduced. As a result, the durability of the RF tag can be improved. The other component adjacent to the bead wrapping on the inner or outer side in the tire width direction can be, for example, a rubber component, such as a rubber bead wrapping. The other component adjacent to the bead wrapping on the inner or outer side in the tire width direction can be, for example, the tire carcass.

[0065] In the case of tires used in passenger cars, the belt reinforcement layer can be further disposed on the radially outer side of the belt. For example, the belt reinforcement layer can be formed by continuously spirally winding cords made of polyethylene terephthalate in the circumferential direction of the tire. Here, the cords can be 6.9 × 10 -2 The belt reinforcement layer, subjected to adhesive treatment at a tension of N / tex or greater, and with an elastic modulus of 2.5 mN / dtex·% measured at 160°C under a load of 29.4 N, can be 2.5 mN / dtex·% or greater. Furthermore, the belt reinforcement layer can be arranged to cover the entire belt or only the two ends of the belt. Additionally, the winding density per unit width of the belt reinforcement layer can vary depending on its position in the width direction. By doing so, road noise and flat spots can be reduced without compromising high-speed durability.

[0066] [Contributions to the UN-led Sustainable Development Goals (SDGs)]

[0067] The SDGs have been advocated for the realization of a sustainable society. One implementation of this disclosure is considered a technology capable of contributing to, for example, “No. 12: Responsible Consumption and Production” and “No. 13: Climate Action”.

[0068] [Explanation of reference numerals in the attached figures]

[0069] 1: Tread surface,

[0070] 2: Circumferential groove,

[0071] 3: Land Division,

[0072] 4: Large blade groove,

[0073] 5: Small knife groove,

[0074] 6: Center groove.

Claims

1. A pneumatic tire, comprising: At least two circumferential grooves extending along the tire circumferential direction on the tread surface. The ribbed land portion is defined between the circumferential grooves. Multiple sipes are arranged in the land section, each sipe extending obliquely relative to the tire width direction. When projected onto the tire width direction, adjacent sipes in the tire circumferential direction at least partially overlap in the tire circumferential direction, or have no spacing in the tire circumferential direction. The sipes are composed of three types: a large sipe with a maximum tilt angle relative to the tire width direction, a small sipe with a minimum tilt angle relative to the tire width direction, and a medium sipe with an intermediate tilt angle relative to the tire width direction between the large sipes and the small sipes. Furthermore, among the large cutter groove, the medium cutter groove, and the small cutter groove, the number of the medium cutter groove is the largest in the distribution of the number of cutter grooves.

2. The pneumatic tire according to claim 1, wherein, In the distribution of the number of adjacent sipes in the entire tire circumferential direction, the number of adjacent large sipes and small sipes in the tire circumferential direction is the smallest.

3. The pneumatic tire according to claim 1 or 2, wherein the number of the central sipes is 33.4% to 60% of the total number of sipes.

4. The pneumatic tire according to claim 3, wherein the number of the central sipes is 37% to 50% of the total number of sipes.

5. The pneumatic tire according to any one of claims 1 to 4, wherein, In the distribution of the number of adjacent sipes in the entire tire circumferential direction, the middle sipe has the largest number of adjacent sipes in the tire circumferential direction.

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