Tire

Abstract

To provide a tire capable of suppressing damage to a communication device.SOLUTION: A tire 1 is equipped with a side rubber 8, a bead filler 4b, a carcass 5 that has a carcass ply 5a including a carcass cord 5c, and a communication device 10. The communication device has an RF tag 10e, and a tag coating rubber 10f covering the RF tag. The communication device is disposed between the side rubber and the bead filler. The 100% modulus M100 of the side rubber is smaller than the 100% modulus M100 of the tag coating rubber portion, and the 100% modulus M100 of the tag coating rubber portion is smaller than the 100% modulus M100 of a contact bead filler portion contacting with the communication device of the bead filler. A loss tangent tanδ of the side rubber is larger than a loss tangent tanδ of the contact bead filler portion, and heat conductivity of the carcass cord is higher than heat conductivity of each of the contact bead filler portion and the tag coating rubber portion.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a tire.

Background Art

[0002] Conventionally, there has been a tire provided with a communication device (such as an RF tag) (Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in conventional tires, there has been room for improvement in suppressing damage to the communication device.

[0005] An object of the present invention is to provide a tire capable of suppressing damage to a communication device.

Means for Solving the Problems

[0006] The tire of the present invention includes side rubber, a bead filler, a carcass having a carcass ply including a carcass cord, a communication device, and is a tire provided with the communication device has an RF tag and a tag covering rubber part covering the RF tag, the communication device is disposed between the side rubber and the bead filler, the 100% modulus M100 of the side rubber is smaller than the 100% modulus M100 of the tag covering rubber part, The 100% modulus M100 of the tag-coated rubber part is smaller than the 100% modulus M100 of the contact bead filler part that contacts the communication device among the bead fillers. The loss tangent tanδ of the side rubber is larger than the loss tangent tanδ of the contact bead filler part. The thermal conductivity of the carcass cord is higher than the thermal conductivities of the contact bead filler part and the tag-coated rubber part, respectively. According to the tire of the present invention, damage to the communication device can be suppressed.

[0007] In the tire of the present invention, the RF tag has an IC chip. When observing only the overlapping region of a tire radial region KR extending 10 mm in the tire radial direction centered on the tire radial position of the center of the IC chip and a tire circumferential region KC extending 70 mm in the tire circumferential direction centered on the tire circumferential position of the center of the IC chip, it is preferable that the volume of the contact bead filler part is larger than the volume of the side rubber, and the volume of the side rubber is larger than the volume of the tag-coated rubber part. Thereby, damage to the communication device can be further suppressed.

[0008] In the tire of the present invention, a bead core, a reinforcing member disposed on the side opposite to the bead core with respect to the carcass around the bead core, is further provided. It is preferable that the tire radial center of the communication device is outside the tire radial outer end of the reinforcing member in the tire radial direction. Thereby, communication performance and durability can be improved.

[0009] In the tire of the present invention, it is preferable that the communication device is in contact with the side rubber. Thereby, communication performance and durability can be improved.

[0010] In the tire of the present invention, the 100% modulus M100 of the side rubber is 0.6 to 0.9 times that of the 100% modulus M100 of the tag-coated rubber part, the 100% modulus M100 of the contact bead filler part is 1.7 times or less that of the 100% modulus M100 of the tag-coated rubber part, it is preferable that the loss tangent tanδ of the side rubber is 2.0 times or less that of the loss tangent tanδ of the contact bead filler part. Thereby, damage to the communication device can be further suppressed.

Advantages of the Invention

[0011] According to the present invention, it is possible to provide a tire capable of suppressing damage to a communication device.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0013] The tire according to the present invention can be suitably used for any type of pneumatic tire, and in particular, can be suitably used for pneumatic tires for trucks and buses.

[0014] Hereinafter, embodiments of the tire according to the present invention will be exemplified and described with reference to the drawings. Members and parts common to the respective figures are denoted by the same reference numerals. In some of the drawings, the tire width direction is indicated by the symbol "WD", the tire diameter direction is indicated by the symbol "RD", and the tire circumferential direction is indicated by the symbol "CD". In this specification, the side closer to the tire inner cavity is referred to as the "tire inner side", and the side farther from the tire inner cavity is referred to as the "tire outer side".

[0015] Figs. 1 to 2 are drawings for explaining a tire 1 according to an embodiment of the present invention. Fig. 1 is a cross-sectional view in the tire width direction showing a part of the tire according to an embodiment of the present invention (specifically, a part on one side with respect to the tire equatorial plane CL) by a cross-section along line A-A of Fig. 2. Fig. 2 is a side view showing a part of the tire of Fig. 1 as viewed from the outer side in the tire width direction. The tire 1 of the embodiment shown in Figs. 1 to 2 is configured as a pneumatic tire for trucks and buses. However, the tire 1 of any embodiment of the present invention may be configured as any type of tire.

[0016] The tire 1 includes a tire body 1M and a communication device 10. The tire body 1M corresponds to the part of the tire 1 other than the communication device 10.

[0017] Hereinafter, unless otherwise specified, the positional relationship, dimensions, etc. of each element are measured in a reference state in which the tire 1 is mounted on an application rim, filled with a specified internal pressure, and is unloaded. Further, in a state where the tire 1 is mounted on an application rim, filled with a specified internal pressure, and loaded with a maximum load, the width in the tire width direction of the ground contact surface in contact with the road surface is referred to as the ground contact width of the tire, and the end in the tire width direction of the ground contact surface is referred to as the ground contact end.

[0018] As used herein, the "applicable rim" refers to an industrial standard effective in the region where pneumatic tires are produced and used. In Japan, it refers to the standard rim (Measuring Rim in the ETRTO's STANDARDS MANUAL, Design Rim in the TRA's YEAR BOOK) for the applicable size described in the JATMA YEAR BOOK of JATMA (Japan Automobile Tire Manufacturers Association), in Europe, it refers to the standard rim for the applicable size described in the STANDARDS MANUAL of ETRTO (The European Tyre and Rim Technical Organisation), and in the United States, it refers to the standard rim for the applicable size described in the YEAR BOOK of TRA (The Tire and Rim Association, Inc.). However, for sizes not described in these industrial standards, it refers to a rim with a width corresponding to the bead width of the pneumatic tire. The "applicable rim" includes sizes that will be described in the aforementioned industrial standards in the future in addition to the current sizes. Examples of "sizes that will be described in the future" may include sizes described as "FUTURE DEVELOPMENTS" in the 2013 edition of ETRTO.

[0019] As used herein, the "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 rating described in industrial standards such as the JATMA YEAR BOOK mentioned above. For sizes not described in the aforementioned industrial standards, it refers to the air pressure (maximum air pressure) corresponding to the maximum load capacity specified for each vehicle on which the tire is mounted. Also, as used herein, the "maximum load" refers to the load corresponding to the maximum load capacity of a tire of the applicable size described in the aforementioned industrial standards, or, in the case of sizes not described in the aforementioned industrial standards, the load corresponding to the maximum load capacity specified for each vehicle on which the tire is mounted.

[0020] First, the tire body 1M will be described. As shown in FIG. 1, the tire body 1M includes a tread portion 1a, a pair of sidewall portions 1b extending radially inward in the tire diameter direction from both end portions in the tire width direction of the tread portion 1a, and a pair of bead portions 1c provided at the radially inner end portions of the respective sidewall portions 1b. The tread portion 1a is the portion in the tire width direction between the pair of grounding ends of the tire body 1M. The bead portion 1c is configured to contact the rim at the radially inner side and the outer side in the tire width direction when the tire 1 is mounted on the rim. The tire body 1M has a pair of tire side portions 1d extending radially inward in the tire diameter direction from both end portions in the tire width direction of the tread portion 1a. The tire side portion 1d is composed of the sidewall portion 1b and the bead portion 1c. Further, the tire body 1M includes a pair of bead cores 4a, a pair of bead fillers 4b, a carcass 5, a belt 6, a tread rubber 7, a side rubber 8, and an inner liner 9.

[0021] Each bead core 4a is embedded in the corresponding bead portion 1c. The bead core 4a includes a plurality of bead wires covered with rubber around the periphery. The bead wire is preferably composed of a metal (for example, steel). The bead wire can be composed of, for example, a monofilament or a stranded wire.

[0022] Each bead filler 4b is located radially outside the corresponding bead core 4a. The bead filler 4b extends in a tapered shape toward the radially outer side of the tire. The bead filler 4b is composed of rubber. Generally, the bead filler may be called a "stiffener". As shown in FIG. 1, the bead filler 4b may be composed of a plurality (two in the example of FIG. 1) of bead filler portions 4b1 and 4b2. The compositions of the rubber constituting these plurality of bead filler portions 4b1 and 4b2 are different from each other. However, for each of the bead filler portions 4b1 and 4b2, the composition of the rubber constituting it is substantially the same throughout the bead filler portions 4b1 and 4b2. These plurality of bead filler portions 4b1 and 4b2 may have different hardnesses, for example. These plurality of bead filler portions 4b1 and 4b2 are arranged (laminated) along the tire radial direction, for example. For example, among these plurality of bead filler portions 4b1 and 4b2, the bead filler portion 4b2 located outermost in the tire radial direction may be softer than the other bead filler portion 4b1. Alternatively, the bead filler 4b may be composed of only one bead filler portion, that is, the composition of the rubber constituting the bead filler 4b may be substantially the same throughout the bead filler 4b. As shown in FIG. 1, the bead filler 4b is in contact with the communication device 10. In this specification, among the one or more bead filler portions 4b1 and 4b2 constituting the bead filler 4b, the bead filler portion in contact with the communication device 10 is referred to as the "contact bead filler portion 4bx". In the example of FIG. 1, the contact bead filler portion 4bx is constituted by the bead filler portion 4b2 located outermost in the tire radial direction among the one or more bead filler portions 4b1 and 4b2 constituting the bead filler 4b.

[0023] The carcass 5 straddles between a pair of bead cores 4a and extends in a toroidal shape. The carcass 5 is composed of one or more (one in the example of FIG. 1) carcass plies 5a. Each carcass ply 5a includes one or a plurality of carcass cords 5c and a covering rubber 5r covering the carcass cords 5c. The carcass cord 5c can be formed of a monofilament or a stranded wire. It is preferable that the carcass cord 5c is made of metal (for example, steel). The carcass ply 5a includes a ply main body portion 5M positioned between a pair of bead cores 4a. The carcass ply 5a may further include a ply turned-up portion 5T that is turned up from both ends of the ply main body portion 5M around the bead core 4a from the inner side in the tire width direction to the outer side in the tire width direction. However, the carcass ply 5a may not include the ply turned-up portion 5T. The ply main body portion 5M is positioned on the inner side in the tire width direction than the bead filler 4b and the bead core 4a. The ply turned-up portion 5T is positioned on the outer side in the tire width direction than the bead filler 4b and the bead core 4a. The carcass 5 is preferably of a radial structure, but may also be of a bias structure.

[0024] The belt 6 is disposed on the outer side in the tire radial direction with respect to the crown portion of the carcass 5. The belt 6 includes one or more (in the example of FIG. 1, four) belt layers 6a. Each belt layer 6a includes one or a plurality of belt cords and a covering rubber that covers the belt cords. The belt cords can be formed of monofilaments or twisted wires. The belt cords are preferably composed of a metal (for example, steel), but may also be composed of organic fibers made of polyester, nylon, rayon, aramid, or the like.

[0025] The tread rubber 7 is positioned on the outer side in the tire radial direction of the belt 6 in the tread portion 1a. The tread rubber 7 constitutes a tread surface that is the outer surface on the outer side in the tire radial direction of the tread portion 1a. A tread pattern is formed on the tread surface.

[0026] The side rubber 8 is positioned in the sidewall portion 1b. The side rubber 8 constitutes the outer surface on the outer side in the tire width direction of the sidewall portion 1b. The side rubber 8 is positioned on the outer side in the tire width direction than the carcass 5. The side rubber 8 is positioned on the outer side in the tire width direction than the bead filler 4b. The side rubber 8 is integrally formed with the tread rubber 7.

[0027] The inner liner 9 is disposed inside the tire of the carcass 5 and may be laminated, for example, on the inner side of the tire of the carcass 5. The inner liner 9 is made of, for example, a butyl rubber with low air permeability. The butyl rubber includes, for example, butyl rubber and halogenated butyl rubber which is a derivative thereof. The inner liner 9 is not limited to butyl rubber and can be made of other rubber compositions, resins, or elastomers.

[0028] As shown in FIG. 1, the tire body 1M may include a reinforcing member 3 around the bead core 4a. The reinforcing member 3 may be disposed on the side opposite to the bead core 4a with respect to the carcass 5. The reinforcing member 3 includes one or more (three in the example of FIG. 1) reinforcing plies 3a. Each reinforcing ply 3a includes a reinforcing cord. The reinforcing cord may be made of metal (e.g., steel) or may be made of organic fibers such as polyester, nylon, rayon, or aramid.

[0029] Next, the communication device 10 will be described. The communication device 10 may be configured to be capable of wireless communication with a predetermined external device (e.g., a reader or a reader / writer) outside the tire 1, and the configuration of the communication device 10 is not particularly limited. The communication device 10 has an RF tag. The RF tag is also called an "RFID tag". The RF tag is preferably configured as a passive type, but may be configured as an active type.

[0030] FIGS. 3 to 4 show an example of the communication device 10. The communication device 10 includes an RF tag 10e and a tag covering rubber part 10f. The RF tag 10e includes an IC chip 10c and an antenna part 10b. In the example of FIGS. 3 to 4, the RF tag 10e is configured as a passive type.

[0031] The IC chip 10c operates, for example, by the dielectric electromotive force generated by the radio waves received by the antenna part 10b. The IC chip 10c has, for example, a control part and a storage part. The memory unit may store any information. For example, the memory unit may store the identification information of Tire 1. The identification information of Tire 1 is, for example, the unique identification information of Tire 1 that can identify each tire, such as the manufacturer, manufacturing factory, and manufacturing date of Tire 1. In addition, the memory unit may store tire history information such as the mileage of the tire, the number of hard braking times, the number of rapid acceleration times, and the number of sharp turning times. Further, for example, sensors for detecting the internal temperature, internal pressure, and acceleration of the tire are provided in the tire cavity, and the memory unit may store the detection information detected by these sensors. In this case, the RF tag 10e can obtain the detection information of the sensors by wirelessly communicating with the sensors through the antenna unit 10b. The control unit is configured to be able to read information from the memory unit.

[0032] The antenna unit 10b has a pair of antennas 10b1 and 10b2. The pair of antennas 10b1 and 10b2 are respectively connected to the ends located on opposite sides of each other in the IC chip 10c. The antenna unit 10b is configured to be able to transmit and receive signals with the above-mentioned predetermined external device outside Tire 1. In the examples of FIGS. 3 to 4, each of the antennas 10b1 and 10b2 extends linearly, but each of the antennas 10b1 and 10b2 may extend in any shape, such as a waveform.

[0033] The tag covering rubber part 10f covers the entire RF tag 10e. The tag covering rubber part 10f is made of rubber. In this example, the tag covering rubber part 10f has a pair of sheet-like tag covering rubber members 10f1 and 10f2. The pair of tag covering rubber members 10f1 and 10f2 are overlapped with each other with the RF tag 10e sandwiched therebetween. It is preferable that the pair of tag covering rubber members 10f1 and 10f2 are fixed to each other by adhesion or the like. However, the tag covering rubber part 10f may be composed of one member. In this example, the tag covering rubber part 10f has a rectangular shape in plan view, but the tag covering rubber part 10f may have any shape in plan view.

[0034] The communication device 10 configured as described above is configured to be able to receive information transmitted on a radio wave or a magnetic field from the above-mentioned predetermined external device by the antenna unit 10b. Electric power is generated in the antenna unit 10b of the communication device 10 by rectification (in the case of a radio wave) or resonance (in the case of a magnetic field), and the storage unit and the control unit of the IC chip 10c perform predetermined operations. For example, the control unit reads out the information in the storage unit and replies (transmits) it from the antenna unit 10b to the above-mentioned predetermined external device on a radio wave or a magnetic field. The above-mentioned predetermined external device receives the radio wave or the magnetic field from the communication device 10. The above-mentioned predetermined external device can acquire the information stored in the storage unit of the IC chip 10c of the communication device 10 by extracting the received information.

[0035] However, the communication device 10 may have an arbitrary configuration different from this example.

[0036] The communication device 10 may have 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. As shown in FIGS. 3 to 4, the longitudinal direction LD of the communication device 10 is parallel to the extending direction of the antenna unit 10b. When each antenna 10b1, 10b2 of the antenna unit 10b has a waveform, the extending direction of the antenna unit 10b refers to the extending direction of the amplitude center line of the waveform formed by each antenna 10b1, 10b2. In the communication device 10, the thickness direction TD of the communication device 10 refers to the thickness direction of the tag-coated rubber portion 10f.

[0037] The length of the longitudinal direction LD of the RF tag 10e is preferably, for example, 20 mm or more, or 50 mm or more. Also, the length of the longitudinal direction LD of the RF tag 10e is preferably, for example, 100 mm or less, or 70 mm or less. The length of the short-side direction SD of the RF tag 10e is preferably, for example, 10 mm or less, or 8 mm or less. The length of the thickness direction TD of the RF tag 10e is preferably, for example, 5 mm or less, or 2 mm or less. The length of the longitudinal direction LD of the communication device 10 is preferably, for example, 30 mm or more, or 60 mm or more. Also, the length of the longitudinal direction LD of the communication device 10 is preferably, for example, 110 mm or less, or 80 mm or less. The length of the short-side direction SD of the communication device 10 is preferably, for example, 20 mm or less, or 15 mm or less. The length of the thickness direction TD of the communication device 10 is preferably, for example, 6 mm or less, or 3 mm or less. The thickness of each of the tag-covering rubber members 10f1 and 10f2 of the tag-covering rubber portion 10f is preferably, for example, 0.5 mm or more. Also, the thickness of each of the tag-covering rubber members 10f1 and 10f2 of the tag-covering rubber portion 10f is preferably, for example, 1 mm or less.

[0038] The entire communication device 10 is embedded inside the tire side portion 1d of the tire body 1M. The communication device 10 is oriented such that the thickness direction TD of the communication device 10 substantially follows the tire width direction (FIG. 1).

[0039] During the manufacture of the tire 1, the green tire constituting the tire body 1M and the communication device 10 are housed inside a tire molding die and vulcanization-molded.

[0040] As shown in FIG. 1, the communication device 10 is embedded inside the sidewall portion 1b. Specifically, the communication device 10 is disposed between the side rubber 8 and the bead filler 4b (specifically, the contact bead filler portion 4bx) in the tire width direction. The communication device 10 is in contact with the outer surface of the bead filler 4b (specifically, the contact bead filler portion 4bx) in the tire width direction. In this way, by embedding the communication device 10 inside the tire body 1M, it is possible to suppress the communication device 10 from coming off or being damaged from the tire body 1M as compared with the case where the communication device 10 is attached on the outer surface of the tire body 1M. In general, metal may weaken the radio waves between the communication device 10 and the above-described predetermined external device (e.g., a reader or a reader / writer), reducing the communication performance between the communication device 10 and the above-described predetermined external device, and thus potentially shortening the communication distance between the communication device 10 and the above-described predetermined external device. On the other hand, in the tire body 1M, metal (e.g., steel) can be used for the carcass 5, belt 6, bead core 4a, reinforcing member 3, etc. And generally, the sidewall portion 1b tends to have less metal content compared to the tread portion 1a. Therefore, by disposing the communication device 10 on the sidewall portion 1b, the communication performance can be improved and the communication distance between the communication device 10 and the above-described predetermined external device can be lengthened compared to the case where the communication device 10 is disposed on the tread portion 1a. Also, by disposing the communication device 10 between the side rubber 8 and the bead filler 4b (specifically, the contact bead filler portion 4bx), the communication performance can be improved, the communication distance between the communication device 10 and the above-described predetermined external device can be lengthened, and the communication device 10 can be disposed in a portion of the tire body 1M that is relatively less distorted during rolling of the tire 1, etc., thus improving the durability of the communication device 10 and hence the tire 1.

[0041] As shown in FIG. 1, it is preferable that the communication device 10 is in contact with the inner surface of the side rubber 8 in the tire width direction. However, there may be a gap between the communication device 10 and the side rubber 8. It is preferable that no other tire constituent members exist between the communication device 10 and the side rubber 8.

[0042] The 100% modulus M100 of the side rubber 8 is smaller than the 100% modulus M100 of the tag-coated rubber portion 10f, and the 100% modulus M100 of the tag-coated rubber portion 10f is smaller than the 100% modulus M100 of the contact bead filler portion 4bx. Here, in this specification, the "100% modulus M100" of a rubber member (such as side rubber 8, tag covering rubber part 10f, contact bead filler part 4bx, etc.) is measured as the modulus tensile elastic modulus (MPa) when a vulcanized rubber test piece of the rubber member with a thickness of 2 mm is stretched by 100% at 25°C based on JIS K 6251 (2017). Generally speaking, the smaller the value of the "100% modulus M100", the easier it is to deform (specifically, a smaller force is required to cause a predetermined deformation). Due to the magnitude relationship of the above-mentioned 100% modulus M100, the side rubber 8 is more likely to deform than the tag covering rubber part 10f, and the tag covering rubber part 10f is more likely to deform than the contact bead filler part 4bx. That is, the tire constituent members located on the outer side in the tire width direction are more likely to deform. On the other hand, generally, when the tire 1 rolls, the tire constituent members located on the outer side in the tire width direction tend to have greater deformation. That is, the side rubber 8 has greater deformation than the tag covering rubber part 10f, and the tag covering rubber part 10f also tends to have greater deformation than the contact bead filler part 4bx. Therefore, due to the magnitude relationship of the above-mentioned 100% modulus M100, each tire constituent member (side rubber 8, tag covering rubber part 10f, contact bead filler part 4bx) can smoothly follow the bending deformation of the tire 1 during tire rolling. Thereby, damage to the communication device 10 caused by the rolling of the tire 1 can be suppressed. By suppressing damage to the communication device 10, even if the tire body 1M fails, it is possible to suppress the communication device 10 from losing its communication function. From the perspective of tire 1 management, etc., it is desirable that the communication device 10 still has a communication function even after the tire 1 is removed from the vehicle for disposal due to failure or the like.

[0043] It is preferable that the 100% modulus M100 of the side rubber 8 is 0.6 to 0.9 times the 100% modulus M100 of the tag covering rubber part 10f. Thereby, damage to the communication device can be further suppressed. Further, it is preferable that the 100% modulus M100 of the contact bead filler portion 4bx is 1.7 times or less of the 100% modulus M100 of the tag-coated rubber portion 10f. Thereby, damage to the communication device can be further suppressed.

[0044] It is preferable that the loss tangent tanδ of the side rubber 8 is larger than the loss tangent tanδ of the contact bead filler portion 4bx. Also, it is preferable that the thermal conductivity of the carcass cord 5c is higher than the respective thermal conductivities of the contact bead filler portion 4bx and the tag-coated rubber portion 10f. Here, in this specification, the "loss tangent tanδ" specifically refers to the loss tangent measured using a spectrometer (manufactured by Ueshima Seisakusho Co., Ltd.) under the conditions of a temperature of 24°C, a strain of 2%, and a frequency of 52 Hz. Generally speaking, the larger the value of the "loss tangent tanδ", the greater the heat generation due to deformation. Also, the "thermal conductivity" of the carcass cord 5c is measured in accordance with JIS R1611:2010, and the rubber members (such as the tread rubber 7, the side rubber 8, the contact bead filler portion 4bx, the tag-coated rubber portion 10f, etc.) are measured in accordance with JIS A1412-2:1999. Due to the above-mentioned magnitude relationship of the loss tangent tanδ, the side rubber 8 is more likely to generate heat due to deformation during the rolling of the tire 1 than the contact bead filler portion 4bx. However, since the side rubber 8 is located on the outermost side of the tire, it has higher heat dissipation performance than the contact bead filler portion 4bx. Thereby, the amount of heat applied to the communication device 10 can be reduced, and thus, damage to the communication device 10 due to heat can be suppressed. Further, due to the magnitude relationship of the above thermal conductivity, the heat generated by the deformation at the ends of the tread rubber 7 and the belt 6 when the tire 1 rolls may be transmitted to the vicinity of the communication device 10 via the carcass cord 5c. However, due to the magnitude relationship of the above loss tangent tanδ and the magnitude relationship of the above thermal conductivity, the contact bead filler portion 4bx located between the carcass cord 5c and the communication device 10 can shield the heat from the carcass cord 5c and effectively suppress the transmission of the heat to the communication device 10. This can also suppress damage to the communication device 10 caused by heat.

[0045] It is preferable that the loss tangent tanδ of the side rubber 8 is 2.0 times or less that of the contact bead filler portion 4bx. Thereby, heat generation in the side rubber 8 can be suppressed, and damage to the communication device 10 can be further suppressed.

[0046] It is preferable that the thermal conductivity of the carcass cord 5c is higher than the respective thermal conductivities of all the rubber members (tread rubber 7, side rubber 8, contact bead filler portion 4bx, tag coating rubber portion 10f, etc.) constituting the tire 1.

[0047] In order to make the thermal conductivity of the carcass cord 5c higher than the respective thermal conductivities of all the rubber members (tread rubber 7, side rubber 8, contact bead filler portion 4bx, tag coating rubber portion 10f, etc.) constituting the tire 1, for example, the carcass cord 5c may be made of metal (for example, steel). This is because metal has a much higher thermal conductivity than rubber.

[0048] It is preferable that the dynamic storage modulus E' of the side rubber 8 is smaller than that of the contact bead filler portion 4bx. Here, in this specification, the "dynamic storage modulus E'" specifically refers to the modulus of elasticity measured under the conditions of a temperature of 24°C, a strain of 2%, and a frequency of 52 Hz using a spectrometer (manufactured by Ueshima Seisakusho Co., Ltd.). Generally speaking, the larger the value of the "dynamic storage modulus E'", the harder the rubber and the more difficult it is to deform, which means excellent durability. If the side cut that has entered the side rubber 8 due to interference with a protrusion or the like penetrates into the inside of the contact bead filler portion 4bx and the communication device 10 is exposed on the cross-section of the side cut, during the rolling of the tire 1, as a result of the side cut repeatedly opening and closing, an unexpected force may act on the communication device 10, causing damage to the communication device 10. In that regard, according to the magnitude relationship of the above-mentioned dynamic storage modulus E', generally speaking, the contact bead filler portion 4bx is harder than the side rubber 8, so it will have better cut resistance. Therefore, the side cut that has entered the side rubber 8 due to interference with a protrusion or the like can be stopped before it penetrates into the inside of the contact bead filler portion 4bx. Thereby, it is possible to suppress the action of an unexpected force on the communication device 10 during the rolling of the tire 1, and suppress damage to the communication device 10.

[0049] It is preferable that the dynamic storage modulus E' of the side rubber 8 is 0.70 to 0.95 times the dynamic storage modulus E' of the contact bead filler portion 4bx. Thereby, damage to the communication device 10 can be further suppressed.

[0050] As a method for adjusting the 100% modulus M100, loss tangent tanδ, and dynamic storage modulus E' of the rubber members (such as the side rubber 8, tag coating rubber portion 10f, contact bead filler portion 4bx, etc.) to satisfy the above-mentioned numerical ranges respectively, for example, the rubber compounding can be selected by choosing a diene polymer from SBR, BR, NR, etc., and among the fillers of 50 to 80 phr, silica can be adjusted within the range of 30 to 80 phr, and the accelerator (known vulcanization accelerators such as DPG, DM, CZ, NS, etc.) can be adjusted within the range of 0.5 to 7 phr, and sulfur (ordinary sulfur, insoluble sulfur) can be adjusted within the range of 0.5 to 10 phr as appropriate.

[0051] In the vicinity of the communication device 10, it is preferable that the volume of the contact bead filler portion 4bx is larger than the volume of the side rubber 8, and the volume of the side rubber 8 is larger than the volume of the tag coating rubber portion 10f. Thereby, the effects due to 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 elastic modulus E’ described above can be further obtained, and thus, damage to the communication device can be further suppressed. From such a viewpoint, when observing only the overlapping region between the tire radial region KR (FIGS. 1 and 2) extending 10 mm in the tire radial direction centered on the tire radial position at the center of the IC chip 10c of the communication device 10 and the tire circumferential region KC (FIG. 2) extending 70 mm in the tire circumferential direction centered on the tire circumferential position at the center of the IC chip 10c, it is preferable that the volume of the contact bead filler portion 4bx is larger than the volume of the side rubber 8, and the volume of the side rubber 8 is larger than the volume of the tag coating rubber portion 10f. Note that the “center of the IC chip 10c” refers to the center of gravity of the IC chip 10c. Specifically, the “tire radial region KR” (FIGS. 1 and 2) is a tire radial region that extends from the tire radial position 5 mm radially inward from the tire radial position at the center of the IC chip 10c to the tire radial position 5 mm radially outward from the tire radial position at the center of the IC chip 10c. Specifically, the “tire circumferential region KC” (FIG. 2) is a tire circumferential region that extends from the tire circumferential position 35 mm in one tire circumferential direction from the tire circumferential position at the center of the IC chip 10c to the tire circumferential position 35 mm in the other tire circumferential direction from the tire circumferential position at the center of the IC chip 10c, and the length of the arc measured along the arc passing through the center of the IC chip 10c and extending in the tire circumferential direction is 70 mm.

[0052] It is preferable that the entire IC chip 10c of the communication device 10 is located within the above overlapping region. Thereby, damage to the communication device 10 can be further suppressed. Also, it is preferable that the entire RF tag 10e of the communication device 10 is located within the overlapping region. Thereby, damage to the communication device 10 can be further suppressed.

[0053] Note that the pointing direction (orientation) of the communication device 10 is arbitrary. However, from the viewpoint of the durability of the communication device 10 and the like, it is preferable that the communication device 10 is pointed so that the longitudinal direction LD of the communication device 10 substantially follows the tire circumferential direction as in the example of FIG. 2. However, the communication device 10 may be pointed so that the short-side direction SD of the communication device 10 substantially follows the tire circumferential direction.

[0054] As shown in FIG. 1, it is preferable that the tire radial center 10m of the communication device 10 (more preferably, the entire communication device 10) is located radially outside the tire radial outer end 5e of the ply turn-up portion 5T of the carcass 5. Thereby, communication performance can be improved, the communication distance between the communication device 10 and the predetermined external device can be lengthened, and the communication device 10 can be arranged in a portion of the tire body 1M where distortion is relatively small during rolling of the tire 1 or the like. Therefore, the durability of the communication device 10 and thus the tire 1 can be improved. This configuration is particularly suitable when the tire 1 is configured as a pneumatic tire for trucks and buses. Here, the "tire radial outer end 5e of the ply turn-up portion 5T of the carcass 5" refers to the tire radial outer end that is the most radially outside among the tire radial outer ends of the ply turn-up portions 5T of the respective carcass plies 5a of the carcass 5. Note that as in the example of FIG. 1, it is preferable that the tire radial center 10m of the communication device 10 coincides with the tire radial position of the center of the IC chip 10c of the communication device 10, but the two may be different.

[0055] As shown in FIG. 1, it is preferable that the tire radial center 10m of the communication device 10 (more preferably, the whole of the communication device 10) is located radially outside the tire of the outer end 3u of the reinforcing member 3. Thereby, the communication performance can be improved, and the communication distance between the communication device 10 and the predetermined external device can be lengthened. Moreover, among the tire body 1M, since the communication device 10 can be arranged in a portion with relatively little distortion during rolling of the tire 1 or the like, the durability of the communication device 10 and thus the tire 1 can be improved. This configuration is particularly suitable when the tire 1 is configured as a pneumatic tire for trucks and buses. Here, the "tire radial outer end 3u of the reinforcing member 3" refers to the tire radial outer end that is the most radially outside among the tire radial outer ends of each reinforcing ply 3a of the reinforcing member 3.

[0056] 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 to 30 mm, and more preferably 5 to 15 mm. This configuration is particularly suitable when the tire 1 is configured as a pneumatic tire for trucks and buses.

[0057] As shown in FIG. 1, it is preferable that the tire radial outer end 5e of the ply turn-up portion 5T of the carcass 5 is located radially inside the tire radial outer end 4bu of the bead filler 4b. However, the tire radial outer end 5e of the ply turn-up portion 5T of the carcass 5 may be located at the same tire radial position as the tire radial outer end 4bu of the bead filler 4b, or radially outside thereof.

[0058] As shown in FIG. 1, it is preferable that the tire radial outer end 3u of the reinforcing member 3 is located radially inside the tire radial outer end 4bu of the bead filler 4b. However, the tire radial outer end 3u of the reinforcing member 3 may be located at the same tire radial position as the tire radial outer end 4bu of the bead filler 4b, or radially outside thereof.

[0059] The tire diameter direction outer end 5e of the ply turn-up portion 5T of the carcass 5 may be located on the tire diameter direction inner side of the tire maximum width position of the tire body 1M, may be located at the same tire diameter direction position as the tire maximum width position of the tire body 1M, or may be located on the tire diameter direction outer side of the tire maximum width position of the tire body 1M, as in the example of FIG. 1. Here, the "tire maximum width position of the tire body 1M" is the tire diameter direction position where the dimension in the tire width direction of the tire body 1M is maximum.

[0060] The tire diameter direction outer end 3u of the reinforcing member 3 may be located on the tire diameter direction inner side of the tire maximum width position of the tire body 1M, may be located at the same tire diameter direction position as the tire maximum width position of the tire body 1M, or may be located on the tire diameter direction outer side of the tire maximum width position of the tire body 1M, as in the example of FIG. 1.

[0061] It is preferable that the tire diameter direction center 10m of the communication device 10 (more preferably, the whole of the communication device 10) is located on the tire diameter direction inner side of the tire maximum width position of the tire body 1M. Thereby, the communication performance can be improved, the communication distance between the communication device 10 and the predetermined external device can be lengthened, and the communication device 10 can be arranged in a portion of the tire body 1M where distortion is relatively small during rolling of the tire 1 or the like. Thus, the durability of the communication device 10 and thus the tire 1 can be improved. This configuration is particularly suitable when the tire 1 is configured as a pneumatic tire for trucks and buses.

Industrial Applicability

[0062] The tire according to the present invention can be suitably used for any type of pneumatic tire, and particularly can be suitably used for pneumatic tires for trucks and buses.

Explanation of Signs

[0063] 1: Tire, 1M: Tire body, 1a: Tread portion, 1b: Sidewall portion, 1c: Bead portion, 1d: Tire side portion, 3: Reinforcing member, 3a: Reinforcing ply, 3u: Tire radial outer end of the reinforcing member, 4a: Bead core, 4b: Bead filler, 4b1, 4b2: Bead filler parts, 4bx: Contact bead filler part, 4bu: Tire radial outer end of the bead filler, 5: Carcass, 5a: Carcass ply, 5c: Carcass cord, 5r: Covering rubber, 5M: Ply main body part, 5T: Ply turning-back part, 5e: Tire radial outer end of the ply turning-back part of the carcass, 6: Belt, 6a: Belt layer, 7: Tread rubber, 8: Side rubber, 9: Inner liner, 10: Communication device, 10e: RF tag, 10b: Antenna part, 10b1, 10b2: Antenna, 10f: Tag covering rubber part, 10f1, 10f2: Tag covering rubber member, 10c: IC chip, 10m: Tire radial center of the communication device, CL: Tire equatorial plane, WD: Tire width direction, RD: Tire radial direction, CD: Tire circumferential direction, LD: Longitudinal direction of the communication device, SD: Short transverse direction of the communication device, TD: Thickness direction of the communication device

Claims

1. A side rubber, a bead filler, a carcass having a carcass ply including a carcass cord, a communication device, A tire comprising: The communication device has an RF tag and a tag covering rubber part covering the RF tag. The communication device is disposed between the side rubber and the bead filler. The 100% modulus M100 of the side rubber is smaller than the 100% modulus M100 of the tag covering rubber part. The 100% modulus M100 of the tag covering rubber part is smaller than the 100% modulus M100 of the contact bead filler part of the bead filler that is in contact with the communication device. The loss tangent tanδ of the side rubber is larger than the loss tangent tanδ of the contact bead filler part. The thermal conductivity of the carcass cord is higher than the respective thermal conductivities of the contact bead filler part and the tag covering rubber part. The loss tangent tanδ is measured under the conditions of a temperature of 24°C, a strain of 2%, and a frequency of 52 Hz. The 100% modulus M100 is measured under the condition of a temperature of 25°C. A tire.

2. The RF tag has an IC chip. When viewing only the overlapping region of a tire radial region KR extending 10 mm in the tire radial direction with the center of the IC chip as the center in the tire radial direction and a tire circumferential region KC extending 70 mm in the tire circumferential direction with the center of the circumferential position of the IC chip as the center in the tire circumferential direction, the volume of the contact bead filler part is larger than the volume of the side rubber, and the volume of the side rubber is larger than the volume of the tag covering rubber part. The tire according to Claim 1.

3. A bead core, a reinforcing member disposed on the side opposite to the bead core with respect to the carcass around the bead core, Further comprising: The tire according to Claim 1 or 2, wherein the tire radial center of the communication device is outside the tire radial outer end of the reinforcing member in the tire radial direction.

4. The communication device is in contact with the side rubber. The tire according to any one of Claims 1 to 3.

5. The 100% modulus M100 of the side rubber is 0.6 to 0.9 times the 100% modulus M100 of the tag covering rubber part. The 100% modulus M100 of the contact bead filler part is 1.7 times or less the 100% modulus M100 of the tag covering rubber part. The loss tangent tanδ of the side rubber is 2.0 times or less of the loss tangent tanδ of the contact bead filler part, the tire according to any one of claims 1 to 4.

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