Pneumatic tire

Abstract

A pneumatic tire is provided, which improves the communication performance of the electronic components and the durability of both the pneumatic tire and the electronic components. The pneumatic tire (1) contains at least one electronic component (21). The electronic component (21) is subjected to a resistivity of 1.0 × 10⁻⁶. 10 The bead is covered with rubber of Ω·cm or more. When the height (Ha) of the bead triangle (8) in the tire radius direction from the outer surface (5a) of the bead core (5) is less than 25mm, the electronic component (21) is disposed in a region 5mm or more but less than 25mm from the outer surface (5a) of the bead core (5) in the tire radius direction. When the height (Ha) of the bead triangle (8) is 25mm or more, the electronic component (21) is disposed in a region 5mm or more from the outer surface (5a) of the bead core (5) in the tire radius direction but less than the outer end (8e) of the bead triangle (8) in the tire radius direction (A2).

Description

Technical Field

[0001] This invention relates to pneumatic tires. Background Technology

[0002] Patent Document 1 describes a pneumatic tire that incorporates internal electronic components, such as RFID (Radio Frequency Identification) tags, capable of communicating with the outside. In Patent Document 1, the electronic components are positioned axially outward from the tire carcass, and the silica content of the rubber components located axially outward from the electronic components is specified. Therefore, the tire of Patent Document 1 ensures sufficient readability of the electronic components and suppresses degradation of tire durability.

[0003] Patent Document 1: International Publication No. 2019-054227

[0004] In recent years, there has been a desire to improve the communication capabilities (readability) of electronic components and the durability of both the pneumatic tire and the electronic components in pneumatic tires as described above. Summary of the Invention

[0005] The present invention was proposed in view of the above-mentioned actual situation, and its main objective is to provide a pneumatic tire that can improve the communication performance of electronic components and the durability of pneumatic tires and electronic components.

[0006] This invention relates to a pneumatic tire, wherein the pneumatic tire includes a pair of bead portions and at least one electronic component, said electronic component having a resistivity of 1.0 × 10⁻⁶. 10 The tire has a rubber covering of Ω·cm or more, and each pair of bead portions is provided with a bead core and a bead triangle extending outward from the outer surface of the bead core in the tire radial direction. When the height of the bead triangle in the tire radial direction from the outer surface of the bead core is less than 25mm, the electronic component is located in a region 5mm or more but less than 25mm outward from the outer surface of the bead core in the tire radial direction. When the height of the bead triangle is 25mm or more, the electronic component is located in a region 5mm or more outward from the outer surface of the bead core in the tire radial direction and below the outer end of the bead triangle in the tire radial direction.

[0007] By employing the above-described structure, the pneumatic tire of the present invention can improve the communication performance of electronic components as well as the durability of the pneumatic tire and electronic components. Attached Figure Description

[0008] Figure 1 This is a radial cross-sectional view of an inflatable tire according to one embodiment of the present invention.

[0009] Figure 2 It is a magnified 3D view of the electronic components.

[0010] Figure 3 This is a radial cross-sectional view of an inflatable tire with a bead height of less than 25mm.

[0011] Figure 4 It is an enlarged cross-sectional view of the tire body, inner liner, and electronic components.

[0012] Figure 5 This is an enlarged cross-sectional view showing the bead portion of the first element.

[0013] Figure 6 This is a cross-sectional view of the electronic components when viewed from the direction of the tire's axis of rotation.

[0014] Figure 7 This is a radial cross-sectional view of the right half of an inflatable tire in another embodiment.

[0015] Figure 8 This is a front view of the reinforcing rubber layer formed as a pneumatic tire, viewed from the direction of the tire's axis of rotation.

[0016] Label Explanation

[0017] 1: Pneumatic tire; 4: Bead section; 5: Bead core; 5a: Outer surface; 8: Bead triangle; 8e: Outer end; Ha: Height of bead triangle; A2: Area; 21: Electronic components. Detailed Implementation

[0018] Hereinafter, one embodiment of the present invention will be described based on the accompanying drawings. To aid in understanding the invention, the drawings include exaggerated representations and show dimensions different from the actual construction. Furthermore, where multiple embodiments exist, the same or common elements are labeled with the same reference numerals in the specification, and repeated descriptions are omitted.

[0019] Figure 1 This is a radial cross-sectional view of a pneumatic tire 1 (hereinafter sometimes simply referred to as "tire") in its normal configuration, showing an embodiment of the present invention, including the tire's axis of rotation Tc. The present invention is suitable, for example, for use as a tire for passenger cars. Additionally, the present invention can also be used for heavy-duty tires and motorcycle tires.

[0020] The term "standard condition" refers to the state in which a tire, when inflated to a specified size, is assembled onto a standard rim, inflated to the specified internal pressure, and is unloaded. When tire sizes are not specified, the term "standard condition" refers to the standard operating condition corresponding to the tire's intended use and is unloaded. In this specification, unless otherwise specified, the dimensions of the tire are values ​​measured under the standard condition.

[0021] "Standard rim" refers to a rim that is specified according to the specifications of each tire within a specification system that includes the specifications on which the tire is based. For example, if it is JATMA, it is "standard rim"; if it is TRA, it is "Design Rim"; and if it is ETRTO, it is "Measuring Rim".

[0022] "Standard tire pressure" refers to the tire pressure specified for each tire according to the specifications system, including the tire's base specifications. If it is JATMA, it is the "maximum tire pressure". If it is TRA, it is the maximum value recorded in the table "TIRE LOAD LIMITS ATVARIOUS COLD INFLATION PRESSURES". If it is ETRTO, it is the "INFLATION PRESSURE".

[0023] like Figure 1 As shown, the tire 1 of this embodiment includes a pair of bead portions 4 and at least one electronic component 21. Additionally, the tire 1 includes a pair of sidewall portions 3 respectively connected to the pair of bead portions 4 and a tread portion 2 respectively connected to the pair of sidewall portions 3.

[0024] A bead core 5 and a bead triangle rubber 8 extending outward from the outer surface 5a of the bead core 5 in the tire radius direction are respectively provided in a pair of bead portions 4.

[0025] Figure 2 This is an enlarged 3D view of electronic component 21. (See image below.) Figure 2 As shown, electronic component 21 is covered by a rubber cover 22. The rubber cover 22 has a diameter of 1.0 × 10⁻⁶ cm. 10 The resistivity is above Ω•cm. This type of cover rubber 22 can suppress noise, radio wave interference, etc., generated in the electronic component 21, thus improving communication performance. Furthermore, the cover rubber 22 can suppress contact between the electronic component 21 and other tire components, improving the durability of the electronic component 21. In this specification, the component consisting of the electronic component 21 and the cover rubber 22 is the electronic module 20.

[0026] Furthermore, this invention is based on the discovery that: the height of the bead triangle rubber 8 in the tire radius direction from the outer surface 5a (outer end in the tire radius direction) of the bead core 5 ( Figure 1 , Figure 3 As shown, the regions with small circumferential shear strain in the tire are different when Ha is greater than 25 mm and when it is less than 25 mm. Figure 3 This is a cross-sectional view of the left half of the tire meridian of tire 1, where the height Ha of the bead triangle rubber 8 is less than 25mm. (Example) Figure 3 As shown, when the height Ha of the bead triangle rubber 8 is less than 25 mm, by arranging the electronic component 21 in a region A1 that is 5 mm or more and 25 mm or less from the outer surface 5a of the bead core 5 outward in the tire radius direction, the shear strain in the tire circumferential direction generated by the electronic component 21 can be reduced. Figure 1 This is a radial cross-sectional view of a tire 1 with a bead triangle rubber 8 height Ha of 25mm or more.

[0027] like Figure 1 As shown, when the height Ha of the bead triangle 8 is 25 mm or more, the electronic component 21 is disposed in region A2, which is at least 5 mm outward from the outer surface 5a of the bead core 5 in the tire radius direction and less than the outer end 8e of the bead triangle 8 in the tire radius direction. This reduces the circumferential shear strain generated by the electronic component 21. Therefore, damage to the tire 1 originating from the electronic component 21 and damage to the electronic component 21 itself can be suppressed, thus improving the durability of both the electronic component 21 and the tire 1. Furthermore, if the electronic component 21 is located too close to the bead core 5, its readability deteriorates due to the influence of the bead core 5. In particular, the readability of the electronic component 21 deteriorates when the bead line (not shown) of the bead core 5 is made of steel or other metal. Therefore, by not disposing of the electronic component 21 at a position less than 5 mm outward from the outer surface 5a in the tire radius direction, its readability can be maintained at a higher level.

[0028] like Figure 1 As typically shown, the tire 1 further comprises: an annular carcass 6 extending between bead cores 5 of a pair of bead portions 4; and an annular inner liner 10 extending between the pair of bead portions 4 inside the carcass 6. Additionally, the tire 1 comprises a sidewall rubber 3G forming the sidewall portion 3 and a bead rubber 4G with a known structure forming the bead portion 4. The sidewall rubber 3G and the bead rubber 4G are constructed using known structures.

[0029] In this embodiment, the tire carcass 6 is, for example, composed of a single tire carcass ply 6A. The tire carcass ply 6A includes, for example, a main body portion 6a and a folded-back portion 6b. The main body portion 6a extends, for example, between two bead portions 4. The folded-back portion 6b is connected to the main body portion 6a and folds back from the inner side to the outer side of the tire axial direction around the bead core 5. In this embodiment, the outer end 6e of the folded-back portion 6b in the tire radial direction is located outside the tire radial direction, beyond the maximum tire width position M. Alternatively, the outer end 6e of the folded-back portion 6b in the tire radial direction may also be located inside the tire radial direction, beyond the maximum tire width position M. The maximum tire width position M is determined by the outermost point of the tire carcass ply 6A in the tire axial direction. In the tread portion 2, a belt layer 7 with a known structure is provided on the outer side of the tire carcass 6 in the tire radial direction.

[0030] Figure 4 It is shown schematically. Figure 1 An enlarged view of the cross-section near the electronic component 21 shown. Figure 4 The diagram shows the tire carcass ply 6A, the inner liner 10, and the electronic components 21. (As shown...) Figure 4 As shown, the carcass ply 6A contains multiple carcass cords 15 (in... Figure 4 The diagram shows a single carcass cord 15 and an adhesive rubber layer 16 covering multiple carcass cords 15.

[0031] The carcass cords 15 are, for example, made of organic fibers such as aramid or rayon. The carcass cords 15 are preferably arranged at an angle of 70° to 90° relative to the tire equator C (illustration omitted).

[0032] Examples of rubber components used in the adhesive rubber layer 16 include isoprene rubber, styrene-butadiene rubber (SBR), butadiene rubber (BR), nitrile rubber (NBR), chloroprene rubber (CR), butyl rubber (IIR), and styrene-isoprene-butadiene copolymer rubber (SIBR). These can be used individually or in combination of two or more types. Isoprene rubber, SBR, and BR are preferred.

[0033] The inner liner 10 is disposed inside the tire carcass 6, forming the tire inner cavity surface 1i. In this embodiment, the inner liner 10 includes an inward surface 10a forming the tire inner cavity surface 1i and an outward surface 10b facing the tire carcass ply 6A in the opposite direction to the inward surface 10a. The inner liner 10 has extremely low air permeability, enabling it to maintain tire internal pressure. The inner liner 10 contains, for example, 80% by mass or more of butyl rubber or halogenated butyl rubber, or other butyl-based rubber. Thus, the inner liner 10 adopts a known structure.

[0034] The tire 1 of this embodiment includes an adhesive rubber layer 12 disposed on the outer side of the inner liner 10 in the tire axial direction. The adhesive rubber layer 12 is disposed, for example, between the inner liner 10 and the carcass 6 (carcass ply 6A). In this embodiment, the adhesive rubber layer 12 extends in a ring shape between a pair of bead portions 4. The adhesive rubber layer 12 improves the adhesion between the carcass ply 6A and the inner liner 10, thereby suppressing their peeling. The adhesive rubber layer 12 is preferably composed, for example, of an elastomer composition comprising natural rubber and styrene-butadiene rubber. In this embodiment, the adhesive rubber layer 12 employs a known structure.

[0035] like Figure 1 and Figure 3 As shown, the bead triangle 8 of this embodiment is formed of a hard rubber with a pointed cross-section that extends obliquely outward from the inner side of the tire axial direction toward the outer side in the tire radial direction. The outer end 8e of the bead triangle 8 is located on the inner side in the tire radial direction, closer to the maximum width position M of the tire. The bead triangle 8 is formed, for example, of a hard rubber with a hardness of 50 degrees or more, and further 60 degrees or more. The rubber hardness is the hardness A hardness measured using a type A hardness tester at 23°C according to JIS-K6253. In addition, the complex elastic modulus E* of the bead triangle 8 is preferably 2MPa to 40MPa, more preferably 10MPa to 30MPa. Furthermore, the loss tangent tanδ of the bead triangle 8 is preferably 0.08 to 0.15. In addition, the complex elastic modulus E* and the loss tangent tanδ are measured using test pieces collected from the bead triangle 8 under the conditions specified in JIS-K6394.

[0036] Initial strain: 10%

[0037] Amplitude: ±2%

[0038] Frequency: 10Hz

[0039] Deformation mode: Stretch

[0040] Measurement temperature: 70℃

[0041] Viscoelastic spectrometer: Manufactured by Iwamoto Manufacturing Co., Ltd.

[0042] The test piece has the following dimensions: length 20mm × width 4mm × thickness 1mm (the tire circumferential direction is the length direction of the test piece, and the tire axial direction is the thickness direction of the test piece).

[0043] The bead core 5, for example, has a polygonal cross-sectional shape obtained by winding multiple rows and layers of bead cord (not shown). In this embodiment, the bead core 5 has a generally quadrilateral cross-sectional shape. The bead core 5 includes an outer surface 5a adjacent to the bead triangle 8, an inner surface 5b facing inwards in the radial direction of the tire, opposite to the outer surface 5a, and a pair of side surfaces 5c connecting the outer surface 5a and the inner surface 5b. The bead cord uses a known structure, for example, made of steel.

[0044] To improve the reading performance of electronic component 21, when the height Ha of the bead triangle rubber 8 is less than 25mm ( Figure 3 (method), and when the height Ha of the bead triangle rubber 8 is 25mm or more ( Figure 1 In each case, the electronic component 21 is preferably positioned at a position 10 mm or more outward from the outer surface 5a of the bead core 5 in the tire radius direction, and more preferably at a position 12 mm or more outward. Furthermore, regarding the electronic component 21, it is preferable to position it in region A3 between the position 5 mm or more outward from the outer surface 5a in the tire radius direction and the tire's maximum width position M. Positioning the electronic component 21 in regions A1 to A3 means that the entire main body 21a (described later) is positioned within regions A1 to A3, and preferably the entire electronic component 21 is positioned within regions A1 to A3. Furthermore, it is more preferable to position the electronic component 21 in regions A1 to A3 as the entire electronic module 20 is positioned within regions A1 to A3.

[0045] Furthermore, the electronic component 21 is more preferably located in a low-strain region where the sum of strains is less than 60% of the maximum value of the sum of strains (illustration omitted). This further improves the durability of the tire 1 and the electronic component 21. The "strain" is numerical data output from the results of a tire simulation (a rolling simulation in which the tire model rolls at least one revolution) performed using a computer as described in Japanese Patent No. 4608306 (hereinafter referred to as the "Patent Patent") (e.g., finite element method). The "strain" is, for example, derived from the plurality of "first elements e1" (…) described in the Patent Patent. Figure 5 (As shown) Output. Furthermore, the "sum of strains" is the sum of six strain components described in the patent publication, consisting of the vertical strains in the tire radial direction, tire circumferential direction, and tire thickness direction, the shear strain due to shear deformation in the tire radial direction, the shear strain due to shear deformation in the tire circumferential direction, and the shear strain due to shear deformation in the tire thickness direction.

[0046] The first element e1 is, for example, assigned to the edge rubber 4G, sidewall rubber 3G, adhesive rubber layer 12, bead triangle rubber 8, and / or inner liner layer 10. Figure 1 (As shown). Figure 5This is an enlarged cross-sectional view showing the bead portion 4 of the first element e1 of this embodiment. (See attached image.) Figure 5 As shown, in this embodiment, a plurality of first elements e1 are assigned to the inner liner 10. In this embodiment, the first elements e1 are assigned to the first elements E1 constituting the outer surface 10b of the inner liner 10. The first elements E1 are arranged continuously, for example, throughout the inner liner 10 in the tire radial direction. In this embodiment, the first elements E1 are assigned at the tire radial height position of the outer surface 5a of the bead core 5 and the outer end 6e (in the tire radial direction) of the folded portion 6b of the carcass ply 6A. Figure 1 The height position in the radial direction of the tire (as shown). In addition, the first element e1 can also be assigned to the adhesive rubber layer 12 adjacent to the outward surface 10b.

[0047] Furthermore, the "boundary conditions" described in the aforementioned patent publication include, for example, a tire 1 under normal load conditions, a rotational speed based on the assumed maximum speed of the tire 1, and the coefficient of friction of the road surface on which the tire 1 travels. The low-strain region is further preferably characterized by a total strain of less than 50% of the maximum value of the total strain. Additionally, as... Figure 5 As shown, the calculation of the low strain region was performed in the tire 1 without the electronic component 21 installed.

[0048] The “normal load” is the load specified for each tire according to each specification in the specification system, including the specifications on which the tire is based. If it is JATMA, it is the “maximum load capacity”; if it is TRA, it is the maximum value recorded in the table “TIRE LOAD LIMITSAT VARIOUS COLD INFLATION PRESSURES”; if it is ETRTO, it is the “LOADCAPACITY”.

[0049] Electronic components 21 are disposed between the tire carcass 6 and the inner liner 10. In this embodiment, on one of the pair of bead portions 4 (in... Figure 1 An electronic component 21 is located on the left side of the tire. However, the location of the electronic component 21 is not limited to this; it can also be located on either side of the tire bead portion 4. Furthermore, multiple electronic components 21 can be provided along the tire circumference.

[0050] like Figure 4 As shown, the electronic component 21 is disposed between the inner liner layer 10 and the adhesive rubber layer 12 in a manner that does not contact the adhesive rubber layer 16. Therefore, the tire 1 of this embodiment can suppress damage caused by contact between the electronic component 21 and the tire carcass cord 15 even when repeated deformation occurs during driving.

[0051] The electronic component 21 may be composed of, for example, any of the following: an RFID tag, a pressure sensor, a temperature sensor, an acceleration sensor, and a magnetic sensor. In this embodiment, the electronic component 21 is an RFID tag. When the RFID tag receives an interrogation wave, it uses the electrical energy and transmits the data stored in its memory as a response wave. Such an RFID tag employs a known structure.

[0052] like Figure 2 As shown, the electronic component 21 of this embodiment includes a main body 21a having an IC chip and an antenna 21b extending in a coil shape. The IC chip is composed of, for example, a transceiver circuit, a control circuit, and a memory. In this embodiment, the antenna 21b includes a coil portion 24a in which metal wire is wound into a spiral shape and an internal space 24b of the coil with the coil portion 24a disposed on the coil central axis K1.

[0053] In the electronic component 21 of this embodiment, the antenna 21b is not directly connected to the main body 21a, and the main body 21a is disposed within the coil internal space 24b of the antenna 21b. Therefore, the main body 21a is protected by the antenna 21b, thus further improving the durability of the electronic component 21. The main body 21a is held in contact with, for example, the outer surface of the wire of the coil 24a. The spiral outer diameter d1 of the antenna 21b ( Figure 4 (As shown) For example, the length is 1.5mm to 2.5mm, preferably 1.8mm to 2.0mm. The total length of the electronic component 21 (including the total length of the antenna 21b) is, for example, about 35mm to 50mm.

[0054] The cover rubber 22 is appropriately made of a known rubber with excellent adhesion. The cover rubber 22 may also be made of an adhesive rubber layer 16 that is bonded to the carcass ply 6A. Figure 2 (As shown) the same rubber.

[0055] The covering rubber 22 has a total length greater than the total length of the electronic component 21, so as to completely cover the electronic component 21. The covering rubber 22 is, for example, formed in a cuboid shape. The length La of the covering rubber 22 is the length in the longitudinal direction of the antenna 21b (the direction of the coil central axis K1), for example, 45 mm to 70 mm. The width Lb of the covering rubber 22 is the length in a direction orthogonal to the longitudinal direction of the antenna 21b, and is smaller than the length La, for example, 8 mm to 15 mm. The thickness ta is the thickness in a direction orthogonal to the length La and the width Lb, and is smaller than the length La and the width Lb, for example, 2.0 mm to 3.0 mm, preferably 2.2 mm to 2.4 mm.

[0056] In this embodiment, the covering rubber 22 includes an adhesive rubber layer 12 ( Figure 4 The outer layer 26 (as shown) is in contact with the inner liner 10. Figure 4(As shown) the inner layer 27 in contact. Furthermore, in this embodiment, the electronic component 21 is disposed between the outer layer 26 covering the rubber 22 and the inner layer 27. The thickness t1 of the inner layer 27 and the thickness t2 of the outer layer 26 are preferably 0.8 mm to 1.5 mm, more preferably 1.0 mm to 1.3 mm. This further improves durability.

[0057] Figure 6 The tire 1 is positioned at the location of the electronic component 21, with the tire equator C ( Figure 1 (As shown) A cross-sectional view cut parallel to the grain. Figure 6 As shown, when viewed from the direction of the tire rotation axis Tc, the coil center axis K1 of the electronic component 21, configured as antenna 21b, is at an angle θ1 within 45 degrees relative to the tire circumference. This mitigates the load generated by the electronic component 21 during driving, thus improving the durability of both the electronic component 21 and the tire 1 (carcass cord 15). The angle θ1 is the angle between the tangent (not shown) to the tire circumferential line Y1 at the midpoint 21c of the length direction of antenna 21b and the coil center axis K1. The angle θ1 is preferably within 25 degrees, and in this embodiment, it is 0 degrees.

[0058] Figure 7 This is a radial cross-sectional view of the right half of tire 1 in another embodiment. (e.g.) Figure 7 As shown, the tire 1 of this embodiment includes a carcass 6 and a reinforcing rubber layer 30. The carcass 6 is, for example, composed of two carcass plies 6A and 6B disposed inside and outside the tire in the radial direction. In this embodiment, the outer end 6e of the folded portion 6b of the inner carcass ply 6A in the radial direction is located further outward in the radial direction than the outer end 6i of the folded portion 6b of the outer carcass ply 6B. Furthermore, the height Ha of the bead triangle 8 in this embodiment is 25 mm or more.

[0059] The reinforcing rubber layer 30 is located, for example, between the bead triangle 8 and the folded portion 6b of the outer carcass ply 6B. In this embodiment, the reinforcing rubber layer 30 extends inward and outward in the tire radius direction from the outer end 8e of the bead triangle 8. The outer end 30e of the reinforcing rubber layer 30 in the tire radius direction is located on the inner side of the tire radius direction, compared to the outer end 6e of the folded portion 6b of the inner carcass ply 6A. The inner end 30i of the reinforcing rubber layer 30 in the tire radius direction is located on the inner side of the tire radius direction, compared to the outer end 6i of the folded portion 6b of the outer carcass ply 6B, and on the outer side of the tire radius direction, compared to the outer surface 5a of the bead core 5. In this embodiment, the reinforcing rubber layer 30 is disposed, for example, on the sidewall portions 3 on both sides (in Figure 7 Only one side is shown in the image. The reinforcing rubber layer 30, for example, includes a plurality of reinforcing cords 30a ( Figure 8(As shown) and the adhesive rubber 30b covering these reinforcing cords 30a. This reinforcing rubber layer 30 increases the rigidity of the sidewall portion 3 or the bead portion 4, thereby improving the durability of the tire 1. In this embodiment, the reinforcing cords 30a are formed of metal, such as steel.

[0060] Figure 8 This is a front view of the reinforcing rubber layer 30 formed as tire 1, viewed from the direction of the tire's rotation axis Tc. (Example) Figure 8 As shown, the reinforcing cord 30a is preferably configured not to be parallel to the coil central axis K1 of the antenna 21b. This helps suppress electromagnetic interference generated in the electronic components 21. To maintain high communication performance, the angle θ2 between the reinforcing cord 30a and the coil central axis K1 is preferably 40 degrees or more, more preferably 65 degrees or more, preferably 140 degrees or less, and more preferably 115 degrees or less. Furthermore, the angle θa of the reinforcing cord 30a relative to the tire circumference is 19 to 26 degrees in this embodiment. Angle θa is the angle of the reinforcing cord 30a at its midpoint 30c in the length direction relative to the tangent line (not shown) of the tire circumference line Y2. Additionally, angle θ2 is the angle between the reinforcing cord 30a and the midpoint 21c in the length direction of the antenna 21b (…). Figure 5 (As shown) The angle between the nearest reinforcing cord 30a and the central axis K1 of the coil.

[0061] The above describes several embodiments of the present invention in detail, but the present invention is not limited to the specific embodiments described above, and can be implemented in various ways.

[0062] [Example]

[0063] Based on the specifications in Table 1, a prototype with... Figure 1 The basic construction of the passenger car tire (Tire A) is sized 285 / 65R17 116H, and it has... Figure 3 The basic construction of the tires is a passenger car tire with dimensions 225 / 30ZR20 85Y XL (Tire B). Each test tire includes... Figure 2 The electronic module is shown. Furthermore, communication performance and durability were tested on each test tire. The general specifications and test methods for the tires are described below.

[0064] Tire A

[0065] Wheel rim: 17×8.5J

[0066] Tire internal pressure: 250 kPa

[0067] Ha: 40mm

[0068] Tire B

[0069] Wheel rim: 20×8.0J

[0070] Tire internal pressure: 290 kPa

[0071] Ha: 15 mm

[0072] <Communication performance>

[0073] The communication performance is expressed exponentially according to the ISO 20912:2020 test method for the suitability of RFID - compliant tires. An RFID reader and an antenna for the RFID reader are used to read the RFID tags inside each test tire, and the reference read signal strength (RSSI: the magnitude of the amplitude of the radio wave) is set to 100. The larger the value of the test result, the stronger the radio wave, indicating better communication performance. Specifically, a value of "30" or more in the test result means sufficient communication and is qualified. In addition, a value less than "30" in the test result means insufficient communication and is unqualified.

[0074] RFID reader: Manufactured by Impinj, Inc. (Model: Speedway R420)

[0075] Antenna for RFID reader: Manufactured by Maspro Denki Kabushiki Kaisha (Model: RAF2031)

[0076] <Durability performance>

[0077] Each test tire travels on a drum test machine under the following specifications. After that, each test tire is disassembled, and the degree of damage to the carcass cords around the electronic components and the degree of damage to the electronic components are confirmed. The degree of damage is evaluated in three grades, A - C, as follows.

[0078] A: No damage or minor damage, and the state where continued use will not have an adverse effect on the tire life and the operation of the electronic components.

[0079] B: Damage greater than A, but a state where there are no problems in the practical use of the tire and the electronic components.

[0080] C: Damage greater than B, and a state that needs improvement.

[0081] Tire A

[0082] Longitudinal load: 14.35 kN

[0083] Tire B

[0084] Longitudinal load: 6.14 kN

[0085] Speed: 120 km / h (common for Tire A and B)

[0086] Travel distance: 20000 km (common for Tire A and B)

[0087] Comparative Examples 1 and 2 mean that the electronic components are located outside region A2, while Comparative Examples 3 and Examples 1-3 mean that the electronic components are located inside region A2. In addition, Comparative Examples 4 and 5 mean that the electronic components are located outside region A1, while Examples 4-6 mean that the electronic components are located inside region A1.

[0088] The test results are shown in Table 1.

[0089] Table 1

[0090]

[0091] As shown in Table 1, it can be understood that the tires of the embodiments exhibit superior durability of the tire (carcass cords) and electronic components compared to the tires of the comparative examples. Furthermore, the tires of the embodiments demonstrate superior communication performance.

[0092] [Postscript]

[0093] The present invention includes the following methods.

[0094] [Invention 1]

[0095] A pneumatic tire, comprising a pair of bead portions and at least one electronic component, the electronic component having a resistivity of 1.0 × 10⁻⁶. 10 The tire has a rubber covering of Ω·cm or more, and each pair of bead portions is provided with a bead core and a bead triangle extending outward from the outer surface of the bead core in the tire radial direction. When the height of the bead triangle in the tire radial direction from the outer surface of the bead core is less than 25mm, the electronic component is located in a region 5mm or more but less than 25mm outward from the outer surface of the bead core in the tire radial direction. When the height of the bead triangle is 25mm or more, the electronic component is located in a region 5mm or more outward from the outer surface of the bead core in the tire radial direction and below the outer end of the bead triangle in the tire radial direction.

[0096] [Invention 2]

[0097] According to the pneumatic tire of the present invention 1, wherein,

[0098] The electronic component is located in a low-strain region where the sum of strains in the region is less than 60% of the maximum sum of strains.

[0099] [Invention 3]

[0100] According to the pneumatic tire of the present invention 1 or 2, wherein,

[0101] The pneumatic tire also includes: an annular carcass extending between the bead cores of the pair of bead portions; and an annular inner liner extending between the pair of bead portions inside the carcass, wherein the electronic components are disposed between the carcass and the inner liner.

[0102] [Invention 4]

[0103] According to the pneumatic tire of the present invention 3, wherein,

[0104] The inner lining contains more than 80% by mass of butyl rubber.

[0105] [Invention 5]

[0106] According to any one of the pneumatic tires of the present invention 1 to 4, wherein,

[0107] The electronic component includes: a main body having an IC chip; and an antenna extending in a coil shape, the antenna not being directly connected to the main body, and the main body being disposed within the coil space of the antenna.

[0108] [Invention 6]

[0109] According to the pneumatic tire of the present invention 5, wherein,

[0110] When viewed from the direction of the tire's rotation axis, the electronic component is configured such that the central axis of the antenna coil is at an angle of less than 45 degrees relative to the tire's circumference.

Claims

1. A pneumatic tire, wherein, The pneumatic tire includes a pair of bead sections and at least one electronic component. The electronic component is covered with a rubber having a resistivity of 1.0 x 10 10 Ω·cm or more. Each of the pair of bead portions is provided with a bead core and a bead triangle extending outward from the outer surface of the bead core in the tire radial direction towards the outer side in the tire radial direction. When the height of the bead triangular rubber from the outer surface of the bead core in the tire radial direction is less than 25 mm, the electronic component is disposed in an area 5 mm to 25 mm outward from the outer surface of the bead core in the tire radial direction. When the height of the bead triangle is 25 mm or more, the electronic component is disposed in a region at least 5 mm outward from the outer surface of the bead core in the tire radius direction and below the outer end of the bead triangle in the tire radius direction.

2. The pneumatic tire according to claim 1, wherein, The electronic component is located in a low-strain region where the sum of strains in the region is less than 60% of the maximum value of the sum of strains.

3. The pneumatic tire according to claim 1 or 2, wherein, The pneumatic tire also includes: A ring-shaped tire carcass extending between the bead cores of the pair of bead portions; and An annular inner liner extends on the inner side of the tire carcass between the pair of bead portions. The electronic components are disposed between the tire body and the inner liner.

4. The pneumatic tire according to claim 3, wherein, The inner lining contains more than 80% by mass of butyl rubber.

5. The pneumatic tire according to claim 1 or 2, wherein, The electronic component includes: The main body, which has an IC chip; and The antenna extends in a coil shape. The antenna is not directly connected to the main body, and the main body is disposed within the coil space of the antenna.

6. The pneumatic tire according to claim 5, wherein, When viewed from the direction of the tire's rotation axis, the electronic component is configured such that the central axis of the antenna coil is at an angle of less than 45 degrees relative to the tire's circumference.

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