tire

Abstract

A tire (1) includes sidewall rubber (8), a bead filler (4b), a carcass (5), and a communication device (10). The communication device has an RF tag (10e) and a tag covering rubber portion (10f) covering the RF tag, and the communication device is arranged between the sidewall rubber and the bead filler. The 100% modulus M100 of the sidewall rubber is lower than the 100% modulus M100 of the tag covering rubber portion, and the 100% modulus M100 of the tag covering rubber portion is lower than the 100% modulus M100 of the contact bead filler portion that is part of the bead filler and contacts the communication device. The loss tangent tanδ of the sidewall rubber is greater than the loss tangent tanδ of the contact bead filler portion, and the thermal conductivity of the carcass cord is higher than the thermal conductivity of the contact bead filler portion and the tag covering rubber portion.

Description

Technical Field

[0001] The present disclosure relates to tires. Background Art

[0002] There already exists a tire including a communication device such as an RF tag (Patent Document 1).

[0003] This application claims priority from Japanese Patent Application No. 2021-199581, filed in Japan on December 8, 2021, the entire contents of which are incorporated herein.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2021-46057 Summary of the Invention

[0007] Problems to be solved by the invention

[0008] However, there is a need for improvement in suppressing damage to the communication device in conventional tires.

[0009] It would be helpful to provide a tire that can inhibit damage to the communication device.

[0010] Solutions for solving problems

[0011] The tire of the present application is the following tire, which comprises:

[0012] sidewall rubber;

[0013] Bead filler;

[0014] a carcass having a carcass ply including carcass cords; and

[0015] Communication device, wherein

[0016] The communication device includes an RF tag and a tag covering rubber portion covering the RF tag.

[0017] The communication device is arranged between the sidewall rubber and the bead filler.

[0018] The 100% modulus M100 of the sidewall rubber is lower than the 100% modulus M100 of the label covering rubber portion, and the 100% modulus M100 of the label covering rubber portion is lower than the 100% modulus M100 of the contact bead filler portion of the bead filler that contacts the communication device.

[0019] The loss tangent tanδ of the sidewall rubber is greater than the loss tangent tanδ of the part that contacts the bead filler, and

[0020] The thermal conductivity of the carcass cord is higher than that of each of the contact bead filler portion and the label covering rubber portion.

[0021] Effects of the Invention

[0022] The present application can provide a tire capable of suppressing damage to a communication device. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] [ Figure 1 ] Figure 1 So along Figure 2 A cross section taken along line AA in FIG. 1 shows a cross-sectional view in the tire width direction of a portion of a tire according to one disclosed embodiment.

[0024] [ Figure 2 ] Figure 2 It shows Figure 1 A side view of a portion of the tire when viewed from the outside in the tire width direction.

[0025] [ Figure 3 ] Figure 3 is a perspective view illustrating an example of a communication device that may be used in a tire according to any of the disclosed embodiments.

[0026] [ Figure 4 ] Figure 4 is shown disassembled Figure 3 An exploded perspective view of a communication device in FIG. DETAILED DESCRIPTION

[0027] The tire of the present application may be suitable for use in any type of pneumatic tire, in particular pneumatic tires for trucks / buses.

[0028] By way of example, embodiments of the tire of the present application will be described below with reference to the accompanying drawings.

[0029] Common components and parts appearing in the drawings are given the same reference numerals. In some of the drawings, the tire width direction is indicated by the reference symbol "WD," the tire radial direction is indicated by the reference symbol "RD," and the tire circumferential direction is indicated by the reference symbol "CD." In this specification, the side closer to the tire inner cavity is referred to as the "tire inner side," while the side farther from the tire inner cavity is referred to as the "tire outer side."

[0030] Figure 1 and Figure 2 A tire 1 according to one disclosed embodiment is shown. Figure 1 So along Figure 2 A cross section taken along line AA in FIG. 1 shows a cross-sectional view in the tire width direction of a portion of a tire according to one disclosed embodiment (specifically, a portion of the tire on a side relative to the tire equatorial plane CL). Figure 2 It shows Figure 1 A side view of a portion of the tire when viewed from the outside in the tire width direction.

[0031] according to Figure 1 and Figure 2 The tire 1 of the embodiment in FIG is a pneumatic tire for trucks / buses. In this respect, the tire 1 according to any of the disclosed embodiments may be any type of tire.

[0032] The tire 1 includes a tire body 1M and a communication device 10. The tire body 1M corresponds to a portion of the tire 1 excluding the communication device 10.

[0033] Unless otherwise specified, the positional relationships and dimensions of various elements are defined based on the reference condition of the tire 1 mounted on an applicable rim, set at a specified internal pressure, and unloaded. The width of the contact patch in the tire width direction that contacts the road surface when the tire 1 is mounted on an applicable rim, set at a specified internal pressure, and subjected to maximum load is referred to as the tire's contact patch width, and the ends of the contact patch in the tire width direction are referred to as contact edges.

[0034] In this specification, the term "applicable rim" refers to a standard rim of an applicable size specified or to be specified in the future in an industry standard effective in the region where pneumatic tires are produced and used (measurement rims in the ETRTO's standard manual and design rims in the TRA's yearbook). For example, the JATMA Yearbook of Japan's JATMA (Japan Automobile Tire Manufacturers Association), the standard manual of Europe's ETRTO (European Tire and Rim Technical Organization), or the yearbook of the U.S.'s TRA (Tire and Rim Association) are examples of applicable sizes. However, for sizes not specified in the above industry standards, the term "applicable rim" refers to a rim having a width corresponding to the bead width of the pneumatic tire. In addition to currently specified sizes, "applicable rim" also includes sizes to be specified in the above industry standards. Examples of "sizes to be specified" may include sizes designated as "FUTURE DEVELOPMENTS" in the 2013 edition of ETRTO.

[0035] In this specification, the term "specified internal pressure" refers to the air pressure (maximum air pressure) corresponding to the maximum load capacity of a single wheel for the applicable size and ply grade, as specified or to be specified in industry standards such as the aforementioned JATMA Yearbook. However, for sizes not specified in the aforementioned industry standards, the term "specified internal pressure" refers to the air pressure (maximum air pressure) corresponding to the maximum load capacity defined for each vehicle on which the tire is mounted. In this specification, the term "maximum load" refers to the load corresponding to the maximum load capacity of the tire of the applicable size defined in the aforementioned industry standards, or, for sizes not defined in the aforementioned industry standards, the load corresponding to the maximum load capacity defined for each vehicle on which the tire is mounted.

[0036] First, the tire body 1M will be described.

[0037] like Figure 1 As shown, the tire body 1M includes a tread portion 1a, a pair of sidewall portions 1b extending radially inward from both ends of the tread portion 1a in the tire width direction, and a pair of bead portions 1c provided at the radially inner end portions of each sidewall portion 1b. The tread portion 1a is the portion of the tire body 1M in the tire width direction between the pair of ground-engaging ends. The bead portions 1c are configured to contact the rim both radially inward and widthwise outward when the tire 1 is mounted on the rim.

[0038] The tire body 1M includes a pair of sidewall portions 1d extending from both ends of the tread portion 1a in the tire width direction toward the inner side in the tire radial direction. The sidewall portion 1d is composed of a sidewall portion 1b and a bead portion 1c.

[0039] The tire body 1M includes a pair of bead cores 4 a , a pair of bead fillers 4 b , a carcass 5 , a belt 6 , a tread rubber 7 , a sidewall rubber 8 , and an inner liner 9 .

[0040] The bead core 4a is embedded in the corresponding bead portion 1c. The bead core 4a includes a plurality of bead wires covered with rubber. The bead wire is preferably made of metal (eg, steel). The bead wire can be composed of, for example, a monofilament or a twisted wire.

[0041] The bead filler 4b is positioned on the outer side of the tire radial direction relative to the corresponding bead core 4a. The bead filler 4b extends toward the outer side of the tire radial direction in a tapered manner. The bead filler 4b is made of rubber.

[0042] Often, bead filler may also be referred to as a "reinforcement member".

[0043] like Figure 1 As shown, the bead filler 4b can be composed of multiple (in Figure 1In the example of the tire, the tire is provided with two bead fillers 4b1 and 4b2. The multiple bead fillers 4b1 and 4b2 differ in the composition of the rubber constituting the respective bead fillers 4b1 and 4b2. In this regard, the composition of the rubber constituting the respective bead fillers 4b1 and 4b2 is substantially uniform throughout the bead fillers 4b1 and 4b2. For example, the multiple bead fillers 4b1 and 4b2 may have different hardnesses. The multiple bead fillers 4b1 and 4b2 may be arranged (stacked) in the radial direction of the tire, for example. For example, among the multiple bead fillers 4b1 and 4b2, the bead filler 4b2 positioned on the outermost side in the radial direction of the tire may be softer than the bead filler 4b1.

[0044] Alternatively, the bead filler 4b may be composed of only one bead filler portion. In other words, the composition of the rubber constituting the bead filler 4b may be substantially uniform over the entire bead filler 4b.

[0045] like Figure 1 As shown, the bead filler 4b is in contact with the communication device 10. In this specification, among the one or more bead filler portions 4b1, 4b2 constituting the bead filler 4b, the bead filler portion in contact with the communication device 10 is referred to as a "contact bead filler portion 4bx". Figure 1 In the example shown in FIG. 5 , the contact bead filler portion 4bx is composed of the bead filler portion 4b2 positioned outermost in the tire radial direction among the one or more bead fillers 4b1 , 4b2 constituting the bead filler 4b.

[0046] The carcass 5 extends between a pair of bead cores 4a and has a ring shape. The carcass 5 is composed of one or more ( Figure 1 The example in FIG is a carcass ply 5a. Each carcass ply 5a includes one or more carcass cords 5c and a covering rubber 5r covering the carcass cords 5c. The carcass cords 5c can be formed of monofilaments or twisted yarns.

[0047] The carcass cords 5c are preferably made of metal (eg, steel).

[0048] The carcass ply 5a includes a ply main body 5M positioned between a pair of bead cores 4a. The carcass ply 5a may further include ply turnbacks 5T extending from both ends of the ply main body 5M and folded around the bead cores 4a from the inner side in the tire width direction toward the outer side in the tire width direction. In this regard, the carcass ply 5a may not include the ply turnbacks 5T.

[0049] The carcass main body 5M is positioned on the inner side in the tire width direction relative to the bead filler 4b and the bead core 4a, while the carcass turn-up portion 5T is positioned on the outer side in the tire width direction relative to the bead filler 4b and the bead core 4a.

[0050] The carcass 5 is preferably of a radial structure and may be of a bias structure.

[0051] The belt 6 is arranged on the outer side of the tire radial direction relative to the crown portion of the carcass 5. The belt 6 includes one or more ( Figure 1 In the example of the present invention, there are four belt layers 6a. Each belt layer 6a includes one or more belt cords and a covering rubber covering the belt cords. The belt cords can be formed of monofilaments or twisted yarns. The belt cords are preferably made of metal (e.g., steel), but can also be made of organic fibers (such as polyester, nylon, rayon, and aramid).

[0052] In the tread portion 1a, a tread rubber 7 is positioned outside the belt 6 in the tire radial direction. The tread rubber 7 constitutes a tread surface, which is a surface outside the tread portion 1a in the tire radial direction. A tread pattern is formed on the tread surface.

[0053] Sidewall rubber 8 is positioned on sidewall portion 1b. Sidewall rubber 8 forms the outer surface of sidewall portion 1b in the tire width direction. Sidewall rubber 8 is positioned outward in the tire width direction relative to carcass 5. Sidewall rubber 8 is positioned outward in the tire width direction relative to bead filler 4b. Sidewall rubber 8 is formed integrally with tread rubber 7.

[0054] The inner liner 9 is arranged on the inner side of the tire body and can be laminated on the inner side of the tire body 5, for example. The inner liner 9 is made of, for example, a butyl-based rubber having low air permeability. Examples of butyl-based rubbers include butyl rubber and halogenated butyl rubber, which is a derivative of butyl rubber. The inner liner 9 is not limited to butyl-based rubber and can be made of other rubber compositions, resins, or elastomers.

[0055] like Figure 1 As shown, the tire body 1M may include a reinforcing member 3 surrounding the bead core 4a. The reinforcing member 3 may be arranged on the opposite side of the tire body 5 from the bead core 4a. The reinforcing member 3 includes one or more ( Figure 1 In the example of the present invention, there are three reinforcing plies 3a. Each reinforcing ply 3a includes a reinforcing cord. The reinforcing cord can be made of metal (for example, steel) or organic fiber (for example, polyester, nylon, rayon, and aramid).

[0056] Next, the communication device 10 will be described.

[0057] The communication device 10 may be of any configuration as long as it enables wireless communication between the communication device 10 and a predetermined external device (eg, a reader or a reader / writer) located outside the tire 1 , and therefore, the configuration of the communication device 10 is not particularly limited.

[0058] The communication device 10 includes an RF tag. The RF tag is also called an "RFID tag." The RF tag is preferably a passive type, but may also be an active type.

[0059] Figure 3 and Figure 4 FIG. 1 shows an example of a communication device 10. The communication device 10 includes an RF tag 10e and a tag covering rubber portion 10f. The RF tag 10e includes an IC chip 10c and an antenna portion 10b. Figure 3 and Figure 4 In the example shown, the RF tag 10e is of a passive type.

[0060] The IC chip 10c operates by, for example, an induced electromotive force generated by radio waves received by the antenna portion 10b. The IC chip 10c includes, for example, a controller and a memory unit.

[0061] The memory unit can store any information. For example, the memory unit can store tire 1's identification information. Tire 1's identification information is unique to tire 1 and can be used to identify each tire from a group of tires, such as tire 1's manufacturer, tire 1's manufacturing plant, and tire 1's manufacturing date. The memory unit can also store tire history information, such as the tire's mileage, number of sudden braking, sudden starts, and sudden cornering. Sensors that detect, for example, tire internal temperature, tire internal pressure, and tire acceleration can also be installed within the tire cavity, and the memory unit can store information detected by the sensors. In this case, the RF tag 10e can wirelessly communicate with the sensors via the antenna unit 10b to obtain the information detected by the sensors.

[0062] The controller is configured to be able to read information from the memory unit.

[0063] The antenna portion 10b includes a pair of antennas 10b1, 10b2. The pair of antennas 10b1, 10b2 are connected to opposite ends of the IC chip 10c, respectively. The antenna portion 10b is configured to allow information to be transmitted to and received from the aforementioned predetermined external device located outside the tire 1. Figure 3 and Figure 4 In the example shown in FIG. 5 , the antennas 10 b 1 , 10 b 2 are both extended in a straight line, but the antennas 10 b 1 , 10 b 2 may be extended to have any shape, such as a wave shape.

[0064] The entire RF tag 10e is covered by the tag covering rubber portion 10f. The tag covering rubber portion 10f is made of rubber.

[0065] In this example, the tag covering rubber portion 10f includes a pair of sheet-like tag covering rubber members 10f1 and 10f2. The pair of tag covering rubber members 10f1 and 10f2 are stacked to sandwich the RF tag 10e between the pair of tag covering rubber members 10f1 and 10f2. The pair of tag covering rubber members 10f1 and 10f2 are preferably fixed to each other by, for example, adhesion.

[0066] In combination with the above, the label covering rubber portion 10f can be constituted by one member.

[0067] In this example, the label covering rubber portion 10f has a quadrangular shape in a plan view. However, the label covering rubber portion 10f may have any shape in a plan view.

[0068] By using the antenna portion 10b, the communication device 10 constructed as described above can receive information transmitted on radio waves or magnetic fields from the above-mentioned predetermined external device. Rectification (in the case of radio waves) or resonance (in the case of magnetic fields) generates power in the antenna portion 10b of the communication device 10, and the memory unit and controller of the IC chip 10c perform predetermined operations. For example, the controller reads the information in the memory unit and returns (transmits) the information on radio waves or magnetic fields from the antenna portion 10b to the above-mentioned predetermined external device. The above-mentioned predetermined external device receives the radio waves or magnetic fields from the communication device 10. The above-mentioned predetermined external device can obtain the received information to obtain the information stored in the memory unit of the IC chip 10c in the communication device 10.

[0069] In conjunction with the above, the communication device 10 may have any configuration other than the configuration shown in this example.

[0070] The communication device 10 may be provided with a longitudinal direction LD, a short side direction SD, and a thickness direction TD. The longitudinal direction LD, the short side direction SD, and the thickness direction TD are perpendicular to each other.

[0071] like Figure 3 and Figure 4 As shown, the longitudinal direction LD of the communication device 10 is parallel to the extension direction of the antenna portion 10b. When antennas 10b1 and 10b2 of the antenna portion 10b have a wave shape, the extension direction of the antenna portion 10b refers to the extension direction of the amplitude centerline of each antenna 10b1 and 10b2. In the communication device 10, the thickness direction TD of the communication device 10 refers to the thickness direction of the label covering rubber portion 10f.

[0072] The length of the RF tag 10e in the longitudinal direction LD is preferably, for example, 20 mm or more or 50 mm or more. The length of the RF tag 10e in the longitudinal direction LD is preferably, for example, 100 mm or less or 70 mm or less.

[0073] The length of the RF tag 10e in the short-side direction SD is preferably, for example, 10 mm or less or 8 mm or less.

[0074] The length of the RF tag 10e in the thickness direction TD is preferably, for example, 5 mm or less or 2 mm or less.

[0075] The length of the communication device 10 in the longitudinal direction LD is preferably, for example, 30 mm or more or 60 mm or more. The length of the communication device 10 in the longitudinal direction LD is preferably, for example, 110 mm or less or 80 mm or less.

[0076] The length of the communication device 10 in the short-side direction SD is preferably, for example, 20 mm or less or 15 mm or less.

[0077] The length of the communication device 10 in the thickness direction TD is preferably, for example, 6 mm or less or 3 mm or less.

[0078] The thickness of each of the label-covering rubber members 10f1 and 10f2 of the label-covering rubber portion 10f is preferably, for example, 0.5 mm or more. The thickness of each of the label-covering rubber members 10f1 and 10f2 of the label-covering rubber portion 10f is preferably, for example, 1 mm or less.

[0079] The entire communication device 10 is embedded in the sidewall portion 1d of the tire body 1M.

[0080] The communication device 10 is oriented so that the thickness direction TD of the communication device 10 is substantially along the tire width direction ( Figure 1 ).

[0081] When the tire 1 is produced, the green tire constituting the tire body 1M and the communication device 10 are housed in a mold for forming a tire and are subjected to vulcanization molding.

[0082] like Figure 1 As shown, the communication device 10 is embedded in the sidewall portion 1b. Specifically, the communication device 10 is positioned between the sidewall rubber 8 and the bead filler 4b (specifically, the bead filler contact portion 4bx) in the tire width direction. The communication device 10 contacts the outer surface of the bead filler 4b (specifically, the bead filler contact portion 4bx) in the tire width direction.

[0083] As described above, by embedding the communication device 10 in the tire body 1M, the communication device 10 can be suppressed from being detached from the tire body 1M or from being damaged, compared to a case where the communication device 10 is attached to the outer surface of the tire body 1M.

[0084] Generally, metal can weaken the radio waves between the communication device 10 and the above-mentioned predetermined external device (for example, a reader or a reader / writer), thereby reducing the communication performance regarding the communication between the communication device 10 and the above-mentioned predetermined external device, and thus the communication distance between the communication device 10 and the above-mentioned predetermined external device can be shortened. In the tire body 1M, metal (for example, steel) can be used in the carcass 5, the belt 6, the bead core 4a, the reinforcing member 3, etc. In addition, the sidewall portion 1b generally tends to have a smaller amount of metal than the tread portion 1a. Therefore, by arranging the communication device 10 in the sidewall portion 1b, the communication performance can be improved compared to the case where the communication device 10 is arranged in the tread portion 1a, and the communication distance between the communication device 10 and the above-mentioned predetermined external device can be extended.

[0085] By placing the communication device 10 between the sidewall rubber 8 and the bead filler 4b (specifically, the contact bead filler portion 4bx), communication performance can be improved, and the communication distance between the communication device 10 and the aforementioned predetermined external device can be extended. Furthermore, the communication device 10 can be placed in a portion of the tire body 1M that is subject to relatively little strain, for example, when the tire 1 is rolling. Consequently, the durability of the communication device 10, and thus the tire 1, can be improved.

[0086] like Figure 1 As shown, the communication device 10 is preferably in contact with the surface of the sidewall rubber 8 on the inner side in the tire width direction.

[0087] In conjunction with the above, a gap may exist between the communication device 10 and the sidewall rubber 8 .

[0088] Preferably, no other tire components exist between the communication device 10 and the sidewall rubber 8 .

[0089] The 100% modulus M100 of the sidewall rubber 8 is lower than the 100% modulus M100 of the label covering rubber portion 10f, and the 100% modulus M100 of the label covering rubber portion 10f is lower than the 100% modulus M100 of the contact bead filler portion 4bx.

[0090] In this specification, the "100% modulus M100" of a rubber member (such as the sidewall rubber 8, the label covering rubber portion 10f, and the contact bead filler portion 4bx) is determined as the modulus or tensile elastic modulus (MPa) when a vulcanized rubber test piece of the rubber member having a thickness of 2 mm is subjected to 100% elongation at 25° C. in accordance with JIS K 6251 (2017). As a general rule, as the value of the "100% modulus M100" is smaller, deformation becomes easier (specifically, the force required for the intended deformation is smaller).

[0091] Based on the magnitude relationship of the 100% modulus M100 described above, the sidewall rubber 8 is more easily deformed than the label covering rubber portion 10f, and the label covering rubber portion 10f is more easily deformed than the contact bead filler portion 4bx. In other words, the tire components are more easily deformed as the tire components are positioned further outward in the tire width direction. Generally, the tire components tend to deform more as the tire components are positioned further outward in the tire width direction. That is, the sidewall rubber 8 tends to deform to a greater extent than the label covering rubber portion 10f, and the label covering rubber portion 10f tends to deform to a greater extent than the contact bead filler portion 4bx. Therefore, based on the magnitude relationship of the 100% modulus M100 described above, the various tire components (the sidewall rubber 8, the label covering rubber portion 10f, and the contact bead filler portion 4bx) can deform to smoothly follow the deflection deformation of the tire 1 as the tire rolls. Therefore, damage to the communication device 10 caused by the rolling of the tire 1 can be suppressed.

[0092] By suppressing damage to the communication device 10, even if the tire body 1M experiences a failure, the loss of the communication function of the communication device 10 can be suppressed. From the perspective of managing the tire 1, it is desirable that the communication device 10 maintains its communication function even after the tire 1 is removed from the vehicle for disposal due to a failure or the like.

[0093] The 100% modulus M100 of the sidewall rubber 8 is preferably 0.6 to 0.9 times the 100% modulus M100 of the label covering rubber portion 10f. This can further reduce damage to the communication device.

[0094] The 100% modulus M100 of the contact bead filler portion 4bx is preferably less than or equal to 1.7 times the 100% modulus M100 of the label covering rubber portion 10f.

[0095] The loss tangent tan δ of the sidewall rubber 8 is preferably larger than the loss tangent tan δ of the portion contacting the bead filler 4bx.

[0096] The thermal conductivity of the carcass cord 5c is preferably higher than the thermal conductivity of the contact bead filler portion 4bx and the label covering rubber portion 10f.

[0097] In this specification, the term "loss tangent tan δ" specifically refers to the loss tangent measured using a spectrometer (Ueshima Seisakusho Co., Ltd.) at a temperature of 24°C, a strain of 2%, and a frequency of 52 Hz. As a general rule, the larger the value of "loss tangent tan δ", the greater the degree of heat generation due to deformation.

[0098] For the carcass cord 5c and rubber members such as the tread rubber 7, the sidewall rubber 8, the contact bead filler portion 4bx and the label covering rubber portion 10f, "thermal conductivity" should be determined according to JIS R 1611:2010, and "thermal conductivity" should be determined according to JIS A 1412-2:1999.

[0099] Based on the aforementioned relationship in terms of loss tangent tanδ, the sidewall rubber 8 tends to generate heat due to deformation during rolling of the tire 1 relative to the contact bead filler portion 4bx. However, since the sidewall rubber 8 is located at the outermost side of the tire, it has higher heat dissipation performance than the contact bead filler portion 4bx. This reduces the amount of heat applied to the communication device 10, thereby preventing thermal damage to the communication device 10.

[0100] Based on the aforementioned magnitude relationship of thermal conductivity, heat generated by deformation of the tread rubber 7 or the end of the belt 6 during rolling of the tire 1 can be transferred through the carcass cords 5c to the vicinity of the communication device 10. However, based on the aforementioned magnitude relationship of the loss tangent tanδ and the aforementioned magnitude relationship of thermal conductivity, the contact bead filler portion 4bx positioned between the carcass cords 5c and the communication device 10 shields the heat from the carcass cords 5c, effectively suppressing heat transfer to the communication device 10. This can also suppress damage to the communication device 10 due to heat.

[0101] The loss tangent tan δ of the sidewall rubber 8 is preferably less than or equal to 2.0 times the loss tangent tan δ of the contact bead filler portion 4bx.

[0102] Thereby, the heat generation at the sidewall rubber 8 can be suppressed, and damage to the communication device 10 can be further suppressed.

[0103] The thermal conductivity of the carcass cord 5 c is preferably higher than the thermal conductivity of each of all rubber members constituting the tire 1 (eg, the tread rubber 7 , the sidewall rubber 8 , the contact bead filler portion 4 bx , and the label covering rubber portion 10 f ).

[0104] In order to set the thermal conductivity of the carcass cord 5c higher than the thermal conductivity of each of the rubber members constituting the tire 1 (e.g., the tread rubber 7, the sidewall rubber 8, the contact bead filler portion 4bx, and the label covering rubber portion 10f), the carcass cord 5c can be made of metal (e.g., steel), for example. This is because metal has a much higher thermal conductivity than rubber.

[0105] The dynamic storage modulus E' of the sidewall rubber 8 is preferably lower than the dynamic storage modulus E' of the contact bead filler portion 4bx.

[0106] In this specification, the term "dynamic storage modulus E'" specifically refers to the elastic modulus determined using a spectrometer (manufactured by Ueshima Seisakusho Co., Ltd.) at a temperature of 24°C, a strain of 2%, and a frequency of 52 Hz. As a general rule, a larger value of "dynamic storage modulus E'" results in harder rubber and less deformation, thereby resulting in better durability.

[0107] In the event that interference with a protrusion or the like causes a side cut in the sidewall rubber 8 to reach the inside of the contact bead filler portion 4bx, and in addition, due to repeated opening and closing of the side cut when the tire 1 rolls, the communication device 10 is exposed at the cross-section of the side cut, and an unexpected force may be applied to the communication device 10, thereby damaging the communication device 10.

[0108] In this regard, as a general rule, based on the aforementioned magnitude relationship of the dynamic storage modulus E', the contact bead filler portion 4bx is harder than the sidewall rubber 8 and therefore has greater shear resistance. Therefore, just before a side cut in the sidewall rubber 8 caused by interference with a protrusion or the like reaches the interior of the contact bead filler portion 4bx, a side cut in the sidewall rubber 8 can be prevented. Consequently, undesirable forces applied to the communication device 10 during rolling of the tire 1 can be suppressed, and damage to the communication device 10 can be prevented.

[0109] The dynamic storage modulus E′ of the sidewall rubber 8 is preferably 0.70 to 0.95 times the dynamic storage modulus E′ of the portion contacting the bead filler 4bx.

[0110] Thereby, damage to the communication device 10 can be further suppressed.

[0111] As an example of a method of adjusting the 100% modulus M100, loss tangent tanδ and dynamic storage modulus E' of rubber members (such as the sidewall rubber 8, the label covering rubber portion 10f and the contact bead filler portion 4bx) to satisfy the corresponding numerical ranges mentioned above, in the rubber formulation, the diene polymer is selected from, for example, SBR, BR and NR, and the filler of 50 to 80 phr includes silica in the range of 30 to 80 phr, an accelerator in the range of 0.5 to 7 phr (a known vulcanization accelerator such as DPG, DM, CZ or NS), and sulfur (ordinary sulfur and insoluble sulfur) in the range of 0.5 to 10 phr, where these ranges are appropriately varied.

[0112] In the vicinity of the communication device 10, the volume of the contact bead filler portion 4bx is preferably greater than the volume of the sidewall rubber 8, and further, the volume of the sidewall rubber 8 is greater than the volume of the label-covering rubber portion 10f. This further enhances the aforementioned effects of the magnitude relationship of the 100% modulus M100, the magnitude relationship of the loss tangent tanδ, and / or the magnitude relationship of the dynamic storage modulus E', thereby further suppressing damage to the communication device.

[0113] From the above-mentioned viewpoint, when only the tire radial area KR ( ) extending over 10 mm in the tire radial direction with the tire radial position of the center of the IC chip 10c of the communication device 10 as the center is observed, Figure 1 and Figure 2 ) and a tire circumferential region KC ( Figure 2 ) in the case of overlapping overlapping areas, preferably, the volume of the contact bead filler portion 4bx is larger than the volume of the sidewall rubber 8, and in addition, the volume of the sidewall rubber 8 is larger than the volume of the label covering rubber portion 10f.

[0114] The term "center of the IC chip 10 c " refers to the center of gravity of the IC chip 10 c.

[0115] Specifically, the "tire radial region KR" ( Figure 1 and Figure 2 ) is a tire radial area defined by a tire radial position spaced 5 mm from the tire radial position of the center of the IC chip 10c toward the tire radial inside as its starting point and a tire radial position spaced 5 mm from the tire radial position of the center of the IC chip 10c toward the tire radial outside as its end point.

[0116] Specifically, the "tire circumferential region KC" ( Figure 2 ) is a tire circumferential area defined by a tire circumferential position spaced 35 mm from the tire circumferential position of the center of the IC chip 10c toward one side of the tire circumference as its starting point and a tire circumferential position spaced 35 mm from the tire circumferential position of the center of the IC chip 10c toward the other side of the tire circumference as its end point, wherein the extended length of the tire circumferential area is 70 mm when the extended length is measured along an arc passing through the center of the IC chip 10c and extending in the tire circumferential direction.

[0117] The entire IC chip 10c in the communication device 10 is preferably positioned in the above-mentioned overlapping region. Thus, damage to the communication device 10 can be further suppressed.

[0118] The entire RF tag 10e of the communication device 10 is preferably positioned in the above-mentioned overlapping region. Thus, damage to the communication device 10 can be further suppressed.

[0119] The direction in which the communication device 10 faces (the orientation of the communication device 10) is arbitrary. However, from the viewpoint of durability of the communication device 10, for example, the communication device 10 is preferably oriented so that the longitudinal direction LD of the communication device 10 is substantially along the tire circumferential direction, as shown in FIG. Figure 2 In this regard, the communication device 10 may be oriented in such a manner that the short side direction SD of the communication device 10 is substantially along the tire circumferential direction.

[0120] like Figure 1 As shown, the tire radial center 10m of the communication device 10 (more preferably, the entire communication device 10) is preferably located radially outward relative to the tire radially outer end 5e of the carcass 5's ply turn-up portion 5T. This improves communication performance and extends the communication distance between the communication device 10 and the aforementioned predetermined external device. Furthermore, the communication device 10 can be positioned in a portion of the tire body 1M, such as one that is subject to relatively low strain during rolling of the tire 1. Consequently, the durability of the communication device 10, and thus the tire 1, can be improved.

[0121] The above-described configuration is particularly preferred when the tire 1 is a pneumatic tire for trucks / buses.

[0122] The term "tire radial outer end 5e of the ply turn-up portion 5T of the carcass 5" refers to the tire radial outer end which is one of the tire radial outer ends of the ply turn-up portion 5T of each carcass ply 5a of the carcass 5 and is located at the outermost side in the tire radial direction.

[0123] like Figure 1 As shown in the example in , the tire radial center 10m of the communication device 10 preferably coincides with the tire radial position of the center of the IC chip 10c of the communication device 10, but the tire radial center 10m may not coincide with the tire radial position.

[0124] like Figure 1 As shown, the tire radial center 10m of the communication device 10 (more preferably, the entire communication device 10) is preferably located radially outward relative to the tire radially outer end 3u of the reinforcing member 3. This improves communication performance and extends the communication distance between the communication device 10 and the aforementioned predetermined external device. Furthermore, the communication device 10 can be positioned in a portion of the tire body 1M, such as one that is subject to relatively low strain during rolling of the tire 1. This improves the durability of the communication device 10, and thus the tire 1.

[0125] The above-described configuration is particularly preferred when the tire 1 is a pneumatic tire for trucks / buses.

[0126] The term “tire radial direction outer end 3 u of the reinforcing member 3 ” refers to a tire radial direction outer end that is one of the tire radial direction outer ends of the respective reinforcing plies 3 a of the reinforcing member 3 and is located outermost in the tire radial direction.

[0127] The tire radial distance between the tire radial center 10m of the communication device 10 and the tire radial outer end 4bu of the bead filler 4b is preferably 1 mm to 30 mm, more preferably 5 mm to 15 mm.

[0128] The above-described configuration is particularly preferred when the tire 1 is a pneumatic tire for trucks / buses.

[0129] like Figure 1 As shown, the tire radial direction outer end 5e of the ply turnup 5T of the carcass 5 is preferably positioned on the tire radial direction inner side relative to the tire radial direction outer end 4bu of the bead filler 4b. However, the tire radial direction outer end 5e of the ply turnup 5T of the carcass 5 may be positioned at the same tire radial direction position as the tire radial direction outer end 4bu of the bead filler 4b, or may be positioned on the tire radial direction outer side relative to the tire radial direction outer end 4bu of the bead filler 4b.

[0130] like Figure 1 As shown, the tire radial direction outer end 3u of the reinforcing member 3 is preferably positioned on the tire radial direction inner side relative to the tire radial direction outer end 4bu of the bead filler 4b. However, the tire radial direction outer end 3u of the reinforcing member 3 may be positioned at the same tire radial direction position as the tire radial direction outer end 4bu of the bead filler 4b, or may be positioned on the tire radial direction outer side relative to the tire radial direction outer end 4bu of the bead filler 4b.

[0131] like Figure 1 As shown in the example, the tire radial outer end 5e of the carcass 5's cord layer folded portion 5T can be positioned radially inward relative to the tire maximum width position of the tire body 1M, and can also be positioned at the same tire radial position as the tire maximum width position of the tire body 1M, and can also be positioned radially outward relative to the tire maximum width position of the tire body 1M.

[0132] The term "tire maximum width position of the tire main body 1M" refers to a tire radial position where the dimension of the tire main body 1M in the tire width direction becomes the largest.

[0133] like Figure 1 As shown in the example, the tire radial outer end 3u of the reinforcing member 3 can be positioned radially inside the tire relative to the tire maximum width position of the tire body 1M, and can also be positioned at the same tire radial position as the tire maximum width position of the tire body 1M, and can also be positioned radially outside the tire relative to the tire maximum width position of the tire body 1M.

[0134] The tire radial center 10m of the communication device 10 (more preferably, the entire communication device 10) is preferably positioned radially inward relative to the tire's maximum width position of the tire body 1M. This improves communication performance and extends the communication distance between the communication device 10 and the aforementioned predetermined external device. Furthermore, the communication device 10 can be positioned in a portion of the tire body 1M, such as one that experiences relatively little strain during rolling of the tire 1. This improves the durability of the communication device 10, and thus the tire 1.

[0135] The above-described configuration is particularly preferred when the tire 1 is a pneumatic tire for trucks / buses.

[0136] Industrial applicability

[0137] The tire of the present application may be suitable for use in any type of pneumatic tire, in particular pneumatic tires for trucks / buses.

[0138] Description of Reference Numerals

[0139] 1: Tires

[0140] 1M: tire body

[0141] 1a: Tread

[0142] 1b: Side wall

[0143] 1c: Bead

[0144] 1d: Sidewall

[0145] 3: Strengthening components

[0146] 3a: Reinforcement ply

[0147] 3u: Tire radial outer end of the reinforcement member

[0148] 4a: bead core

[0149] 4b: Bead filler

[0150] 4b1, 4b2: Bead filling part

[0151] 4bx: Contact with tire bead filler

[0152] 4bu: radial outer end of the tire bead filler

[0153] 5: Carcass

[0154] 5a: Carcass ply

[0155] 5c: carcass cord

[0156] 5r: Covering rubber

[0157] 5M: ply body

[0158] 5T: Carpet layer folding part

[0159] 5e: The radially outer end of the carcass ply foldback

[0160] 6: Belt

[0161] 6a: Belt

[0162] 7: Tread rubber

[0163] 8: Sidewall rubber

[0164] 9: Lining layer

[0165] 10: Communication device

[0166] 10e: RF tag

[0167] 10b: Antenna

[0168] 10b1, 10b2: Antenna

[0169] 10f: Label covering the rubber part

[0170] 10f1, 10f2: Label covering rubber member

[0171] 10c: IC chip

[0172] 10m: Tire radial center of the communication device

[0173] CL: Tire equatorial plane

[0174] WD: tire width direction

[0175] RD: Tire Radial

[0176] CD: Tire circumferential direction

[0177] LD: vertical direction of communication device

[0178] SD: Short side direction of the communication device

[0179] TD: thickness direction of the communication device

Claims

1. A tire comprising: sidewall rubber; Bead filler; a carcass having a carcass ply including carcass cords; and Communication device, wherein The communication device includes an RF tag and a tag covering rubber portion covering the RF tag. The communication device is arranged between the sidewall rubber and the bead filler, The 100% modulus M100 of the sidewall rubber is lower than the 100% modulus M100 of the label covering rubber portion, The 100% modulus M100 of the label covering rubber portion is lower than the 100% modulus M100 of the contacting bead filler portion of the bead filler that contacts the communication device. The loss tangent tanδ of the sidewall rubber is greater than the loss tangent tanδ of the bead filler contact portion, and the carcass cord has a thermal conductivity higher than that of each of the bead filler contact portion and the label covering rubber portion, The 100% modulus M100 is determined as the modulus or tensile elastic modulus when a vulcanized rubber test piece of a rubber member having a thickness of 2 mm is subjected to 100% elongation at 25° C. according to JIS K 6251 of 2017. The loss tangent tanδ specifically refers to the loss tangent determined using a spectrometer at a temperature of 24°C, a strain of 2% and a frequency of 52 Hz. For carcass cords, the thermal conductivity should be determined in accordance with JIS R 1611:2010, and for rubber members, the thermal conductivity should be determined in accordance with JIS A1412-2:1999.

2. The tire according to claim 1, wherein The RF tag includes an IC chip, and When observing only the overlapping area between the tire radial area KR extending over 10 mm in the tire radial direction with the tire radial position centered on the center of the IC chip and the tire circumferential area KC extending over 70 mm in the tire circumferential direction with the tire circumferential position centered on the center of the IC chip, the volume of the contact bead filler portion is greater than the volume of the sidewall rubber, and in addition, the volume of the sidewall rubber is greater than the volume of the label covering rubber portion.

3. The tire according to claim 1 or 2, further comprising: bead core; and a reinforcing member surrounding the bead core, the reinforcing member being arranged on a side opposite to the bead core relative to the carcass, wherein A tire radial direction center of the communication device is located outside in the tire radial direction relative to a tire radial direction outer end of the reinforcing member.

4. The tire according to claim 1, wherein The communication device is in contact with the sidewall rubber.

5. The tire according to claim 1, wherein The 100% modulus M100 of the sidewall rubber is 0.6 to 0.9 times the 100% modulus M100 of the label covering rubber portion, The 100% modulus M100 of the bead filler contacting portion is less than or equal to 1.7 times the 100% modulus M100 of the label covering rubber portion, The loss tangent tanδ of the sidewall rubber is less than or equal to 2.0 times the loss tangent tanδ of the bead filler contacting portion.

Images