Tire for heavy load

Abstract

To provide a tire 2 for heavy load which is good at reading performance of data from RFID tag and moreover is good at endurance.SOLUTION: A tire 2 comprises a tread, a pair of side walls, a pair of beads, a carcass, a belt, a pair of chafers and a tag member which contains RFID tag. The bead of the tire 2 comprises a core and an apex. In the tire 2, the carcass comprises a carcass ply which contains a carcass cord and the carcass cord is composed of an organic fiber. The carcass ply comprises a ply body which crosses between a pair of beads and a pair of folding parts which links to the ply body and are folded by the beads. The tire 2 provides the tire of normal state with the load of 50% of the regular load and then end of the folding part is located on axial direction inside rather than axial direction outside of a rim in standard ground state that brings the tire into contact with a plane and the RFID tag is located on axial direction outside rather than axial direction the RFID tag is located axially outside of the rim's axial outer end and radially outside of the rim's radial outer end. The tire 2 is configured so that angle which determines between a length direction of the RFID tag and the carcass cord is 80° or more and 90°or less.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a heavy duty tire. [Background technology]

[0002] Tires equipped with RFID (Radio Frequency Identification) tags that read and write data via radio waves have been proposed for managing tire manufacturing control, customer information, driving history, etc. Various studies have been conducted on technologies for attaching RFID tags to tires (for example, Patent Document 1). Patent Document 1 proposes a technology for attaching RFID tags to heavy-duty tires used on trucks and buses.

[0003] Heavy-duty tires used on trucks and buses generally employ steel cords as tire cords such as carcass cords. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-046057 Summary of the Invention [Problem to be solved by the invention]

[0005] If an RFID tag is attached to a tire that uses steel cord as the carcass cord, the steel cord will act as a barrier to radio waves, making it difficult to read data from the RFID tag.

[0006] An object of the present invention is to provide a heavy-duty tire that has good performance in reading data from an RFID tag and also has good durability. In the present invention, a tire having good durability means that the tire can travel a long distance and the RFID tag is not easily damaged. [Means for solving the problem]

[0007] A heavy-duty tire according to one aspect of the present invention comprises: Tread and a pair of sidewalls connected to the ends of the tread and positioned radially inward of the tread; a pair of beads located radially inside the sidewall; a carcass located inside the tread and the pair of sidewalls and spanning between one bead and the other bead; a belt laminated on the carcass on a radially inner side of the tread; a pair of chafers located radially inside the sidewalls and in contact with the rim; A tire comprising a tag member including an RFID tag, The bead includes a core and an apex located radially outward of the core, The carcass includes a carcass ply including a plurality of carcass cords arranged in parallel, the carcass cord is made of organic fiber, The carcass ply includes a ply body that spans between the pair of beads, and a pair of turn-up portions that are connected to the ply body and turned up at the beads, The rim is a regular rim, The state in which the tire is mounted on the rim and the internal pressure of the tire is adjusted to a normal internal pressure is the normal state, A state in which a load of 50% of the normal load is applied to the tire in the normal state and the tire is brought into contact with a flat surface is the standard contact state, In the standard ground contact state, an end of the folded-up portion is located axially inward from an axially outer end of the rim, In the standard grounding state, the RFID tag is located axially outward from an axially outer end of the rim, and radially outward from a radially outer end of the rim; The angle formed between the length direction of the RFID tag and the carcass cord is 80 degrees or more and 90 degrees or less. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a heavy-duty tire that has good performance in reading data from an RFID tag and good durability. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a cross-sectional view showing a part of a heavy duty tire according to one embodiment of the present invention. [Figure 2] FIG. 2 is a cross-sectional view showing a part of the heavy duty tire of FIG. [Figure 3] FIG. 3 is a plan view of the tag member. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. [Figure 5] FIG. 5 is a cross-sectional view showing a part of a heavy duty tire in a ground contact state. [Figure 6] FIG. 6 is a diagram illustrating the angle formed between the length direction of the RFID tag and the carcass cord. [Figure 7] FIG. 7 is a cross-sectional view showing a part of a heavy duty tire according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0010] The tire of the present invention is mounted on a rim. The inside of the tire is filled with air, and the internal pressure of the tire is adjusted. A tire mounted on a rim is also called a tire-rim assembly. A tire-rim assembly includes a rim and a tire mounted on the rim.

[0011] In the present invention, a state in which a tire is mounted on a standard rim, the internal pressure of the tire is adjusted to a standard internal pressure, and no load is applied to the tire is referred to as a standard state.

[0012] In the present invention, unless otherwise specified, the dimensions and angles of each part of the tire are measured in a normal state. The dimensions and angles of each part of the tire's meridian cross section, which cannot be measured when the tire is mounted on a regular rim, are measured on a cut surface of the tire obtained by cutting the tire along a plane including the rotation axis. In this measurement, the tire is set so that the distance between the left and right beads matches the distance between the beads of the tire mounted on a regular rim. Note that the tire configuration, which cannot be confirmed when the tire is mounted on a regular rim, is confirmed on the cut surface.

[0013] A genuine rim is a rim specified in the standard on which the tire is based. The "standard rim" in the JATMA standard, the "design rim" in the TRA standard, and the "measuring rim" in the ETRTO standard are all genuine rims.

[0014] Normal tire pressure refers to the pressure specified in the standard on which the tire is based. The "maximum tire pressure" in the JATMA standard, the "maximum tire pressure" listed in the TRA standard's "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURE" and the "INFLATION PRESSURE" in the ETRTO standard are normal tire pressures.

[0015] Normal load refers to the load specified in the standard on which the tire is based. The "maximum load capacity" in the JATMA standard, the "maximum value" listed in the "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES" in the TRA standard, and the "LOAD CAPACITY" in the ETRTO standard are normal loads.

[0016] In the present invention, the crosslinked rubber is a molded article obtained by pressurizing and heating a rubber composition. The crosslinked rubber is a crosslinked product of the rubber composition. This rubber composition is a material obtained by mixing a base rubber and chemicals in a kneader such as a Banbury mixer. The base rubber of the rubber composition is not crosslinked. The base rubber of the crosslinked rubber is crosslinked. The crosslinked rubber is also called vulcanized rubber, and the rubber composition is also called unvulcanized rubber.

[0017] Examples of base rubbers include natural rubber (NR), butadiene rubber (BR), styrene butadiene rubber (SBR), isoprene rubber (IR), ethylene propylene rubber (EPDM), chloroprene rubber (CR), acrylonitrile butadiene rubber (NBR), and butyl rubber (IIR). Examples of chemicals include reinforcing agents such as carbon black and silica, plasticizers such as aromatic oil, fillers such as zinc oxide, lubricants such as stearic acid, antioxidants, processing aids, sulfur, and vulcanization accelerators. The selection of base rubber and chemicals, the content of the selected chemicals, etc. are determined appropriately depending on the specifications of each element to which the rubber composition is applied, such as the tread and sidewall.

[0018] In the present invention, the tire comprises a tread portion, a pair of bead portions, and a pair of sidewall portions. The tread portion is the portion of the tire that comes into contact with the road surface. The bead portions are the portions of the tire that fit onto the rim. The sidewall portions are the portions of the tire that bridge between the tread portion and the bead portions.

[0019] In the present invention, the complex modulus of an element made of crosslinked rubber among elements constituting a tire is measured in accordance with the provisions of JIS K 6394. The measurement conditions are as follows. Initial strain = 10% Dynamic strain = ±1% Frequency = 10 Hz Mode = Decompression mode Temperature=70℃ In this measurement, a test piece (length 40 mm x width 4 mm x thickness 1 mm) is sampled from the tire. The longitudinal direction of the test piece is aligned with the circumferential direction of the tire. If it is not possible to sample a test piece from the tire, the test piece is sampled from a sheet of crosslinked rubber (hereinafter also referred to as a rubber sheet) obtained by pressing and heating the rubber composition used to form the element to be measured at a temperature of 170°C for 12 minutes. In the present invention, the complex modulus is expressed as a loss tangent at 70°C.

[0020] [Findings that form the basis of the present invention] When attaching an RFID tag to a heavy-duty tire, the RFID tag is generally embedded in the bead portion, which is less susceptible to deformation. Heavy-duty tires used on trucks and buses are generally all-steel tires, which use steel cord as reinforcing material in both the carcass and belt due to their operating conditions. Because all-steel tires have a high amount of steel (metal), RFID tags attached to them are prone to interference with radio wave transmission due to the metal, resulting in poor reading performance.

[0021] Furthermore, when heavy-duty tires equipped with RFID tags are mounted on a vehicle, depending on the location of the RFID tag on the tire, there is a problem in that the transmission of radio waves may be obstructed by metal rims such as aluminum wheels, making reading the tag difficult.

[0022] As a solution to these problems, the latter problem can be solved by attaching the RFID tag at a position away from the metal wheel. On the other hand, regarding the former problem, it can be considered to replace steel cords (hereinafter referred to as steel cords) with organic fiber cords (hereinafter referred to as organic fiber cords). However, when organic fiber cords are used as carcass cords instead of steel cords, distortion near the ends of the folded-up portions of the carcass tends to increase, which creates a new problem in that the durability of heavy-duty tires tends to decrease.

[0023] Therefore, the present inventors have investigated means for ensuring good reading performance of RFID tags without impairing the durability of heavy-duty tires. As a result, the inventors discovered that by attaching a tag member including an RFID tag to a tire in a predetermined position and in a predetermined orientation, employing organic fiber cords as the carcass cords, and arranging the carcass so that the end of the folded-back portion of the carcass ply is in a predetermined position, it is possible to ensure good reading performance of the RFID tag without compromising the durability of the heavy-duty tire, and completed the invention described below.

[0024] [Details of the embodiment of the present invention] Hereinafter, the present invention will be described in detail based on preferred embodiments, with appropriate reference to the drawings. 1 shows a part of a heavy-duty tire 2 (hereinafter also simply referred to as "tire 2") according to one embodiment of the present invention. This tire 2 is mounted on vehicles such as trucks and buses. In FIG. 1, a tire 2 is mounted on a rim R (regular rim).

[0025] Fig. 1 shows a portion of a cross section (hereinafter referred to as a meridian cross section) of this tire 2 taken along a plane including the rotation axis of the tire 2. In Fig. 1, the left-right direction is the axial direction of the tire 2, and the up-down direction is the radial direction of the tire 2. The direction perpendicular to the plane of Fig. 1 is the circumferential direction of the tire 2. FIG. 2 shows a portion of the cross section shown in FIG.

[0026] 1, a dashed line CL extending in the radial direction represents the equatorial plane of the tire 2. A solid line BBL extending in the axial direction in Figures 1 and 2 is a bead base line. The bead base line is a line that defines the rim diameter of the rim R (see JATMA, etc.).

[0027] The tire 2 includes a tread 4, a pair of sidewalls 6, a pair of chafers 8, a pair of beads 10, a carcass 12, a pair of cushion layers 14, a pair of steel fillers 16, an inner liner 18, a reinforcing layer 20, and a tag member 26.

[0028] The tread 4 is located radially outward of the carcass 12. The tread 4 comes into contact with the road surface at a tread surface 24. At least three circumferential grooves 28 are formed in the tread 4. As a result, the tread 4 defines at least four land portions 30. 1 has three circumferential grooves 28 formed in the tread 4, which define four land portions 30. These land portions 30 are arranged in parallel in the axial direction and extend continuously in the circumferential direction.

[0029] Of the three circumferential grooves 28 cut in the tread 4, the circumferential groove 28 located on the outer side in the axial direction is the shoulder circumferential groove 28s. The circumferential groove 28 sandwiched between the two shoulder circumferential grooves 28s in the axial direction and located on the equatorial plane is the center circumferential groove 28c. In this tire 2, the three circumferential grooves 28 are configured by the center circumferential groove 28c and a pair of shoulder circumferential grooves 28s.

[0030] Of the four land portions 30 formed in the tread 4, the land portion 30 located on the outer side in the axial direction is the shoulder land portion 30s. The shoulder land portion 30s is located on the outer side of the shoulder circumferential groove 28s in the axial direction, and includes the edge PE of the tread surface 24. The land portion 30 located on the inner side of the shoulder land portion 30s in the axial direction is the middle land portion 30m. The middle land portion 30m is located between the center circumferential groove 28c and the shoulder circumferential groove 28s in the axial direction. In this tire 2, the four land portions 30 are formed by a pair of middle land portions 30m and a pair of shoulder land portions 30s.

[0031] The tread 4 includes a base portion 32 and a cap portion 34 located radially outward of the base portion 32. The base portion 32 is made of a cross-linked rubber with low heat buildup. The cap portion 34 is made of a cross-linked rubber that takes into consideration wear resistance and grip performance. As shown in FIG. 1 , the base portion 32 covers the entire reinforcing layer 20. The cap portion 34 covers the entire base portion 32. The cap portion 34 includes the tread surface 24.

[0032] 1, the position indicated by the symbol PC is the equator. The equator PC is the intersection of the tread surface 24 and the equatorial plane. When the grooves 28 are located on the equatorial plane, as in this tire 2, the equator PC is determined based on a hypothetical tread surface obtained assuming that the grooves 28 do not exist. The radial distance from the bead base line to the equator PC obtained in the tire 2 in a normal state is the section height of this tire 2 (see JATMA, etc.).

[0033] Each sidewall 6 is continuous with an edge of the tread 4. The sidewalls 6 are located radially inward of the tread 4. The sidewalls 6 are located axially outward of the carcass 12. The position indicated by the symbol PS is the inner end of the sidewall 6. The sidewall 6 is made of a crosslinked rubber that is cut-resistant. The complex modulus of elasticity of the sidewall is 2.0 MPa or more and 6.0 MPa or less.

[0034] The position indicated by the symbol PW is the axial outer end (hereinafter referred to as the outer end PW) of the tire 2. If there is a decoration such as a pattern or lettering on the outer surface, the outer end PW is determined based on a virtual outer surface obtained assuming that there is no decoration. The tire 2 has its maximum width at the outer end PW. The outer end PW is also called the maximum width position. In the present invention, the maximum width position PWb is the reference maximum width position PW of the tire 2 in a normal state. The axial distance from one reference maximum width position PWb to another reference maximum width position PWb (not shown) is the cross-sectional width of the tire 2 (see JATMA, etc.).

[0035] 1, the length indicated by the symbol H is the radial distance from the bead base line to the reference maximum width position PWb. The radial distance H is also called the radial height of the reference maximum width position PWb. In the tire 2 in a normal state, the ratio of the radial height H at the reference maximum width position PWb to the cross-sectional height is equal to or greater than 0.40 and is equal to or less than 0.60.

[0036] Each chafer 8 is located radially inward of the sidewall 6. The chafer 8 contacts the rim R. The position indicated by the symbol PB is the outer end of the chafer 8. The chafer 8 is made of a crosslinked rubber that is designed for wear resistance. The complex modulus of the chafer 8 is 10 MPa or more and 15 MPa or less. The chafer 8 is harder than the sidewall 6.

[0037] Each bead 10 is located axially inward of the chafer 8. The bead 10 is located radially inward of the sidewall 6. Each bead 10 includes a core 36 and an apex 38.

[0038] The core 36 extends in the circumferential direction and includes a core body 36m and a wrapping layer 36r. The core body 36m is a ring extending in the circumferential direction. The core body 36m includes a steel wire wound in the circumferential direction. The cross-sectional shape of the core body 36m is arranged by regularly winding the wire. As a result, in the cross section of the core body 36m, cross-sectional units each made of cross sections of a plurality of wires arranged in parallel in the approximately axial direction are stacked in multiple stages in the approximately radial direction. The cross-sectional shape of the core body 36m is represented by a line circumscribing the core body 36m. As shown in FIG. 1, the core body 36m has a hexagonal cross-sectional shape. This core body 36m may also have a quadrilateral cross-sectional shape.

[0039] The core body 36m has approximately six side surfaces 36ms. As shown in FIG. 1 , one side surface 36msb of the six side surfaces 36ms is arranged to face the seat Rs of the rim R. In this embodiment, the side surface 36msb arranged to face the seat Rs of the rim R is the bottom surface of the core body 36m. The core body 36m has a bottom surface 32msb arranged to face the seat Rs of the rim R. In a meridian cross section of the tire 2, the outline of the bottom surface 32msb is represented by a straight line.

[0040] The wrapping layer 36r surrounds the periphery of the core body 36m. The wrapping layer 36r covers the core body 36m. The wrapping layer 36r prevents the core body 36m from coming apart. The wrapping layer 36r is not particularly limited in configuration as long as it can prevent the core body 36m from coming apart. The wrapping layer 36r is made of a cord wound spirally around the core body 36m, a rubberized cloth wrapped around the core body 36m, or the like.

[0041] The apex 38 is located radially outward from the core 36. The apex 38 extends radially outward from the core 36. The apex 38 tapers outward. An outer end PA of the apex 38 is located radially outward from an outer end PB of the chafer 8.

[0042] The apex 38 includes an inner apex 40 and an outer apex 42. The inner apex 40 is located radially outward of the core 36. The outer apex 42 is located radially outward of the inner apex 40.

[0043] The inner apex 40 is tapered outward. The inner apex 40 is made of a hard crosslinked rubber. The complex modulus of elasticity of the inner apex 40 is 60 MPa or more and 90 MPa or less.

[0044] The outer apex 42 is thick near the outer end PU of the inner apex 40. The outer apex 42 tapers inward from this thick portion and then tapers outward. An inner end PG1 of the outer apex 42 is located near the core 36. An outer end PG2 of the outer apex 42 is also an outer end PA of the apex 38.

[0045] The outer apex 42 is made of crosslinked rubber and is softer than the inner apex 40. The complex modulus of elasticity of the outer apex 42 is 3.0 MPa or more and 6.0 MPa or less.

[0046] The carcass 12 is located inside the tread 4, the pair of sidewalls 6, and the pair of chafers 8. The carcass 12 bridges between the pair of beads 10. The carcass 12 of the tire 2 has a radial structure.

[0047] The carcass 12 includes at least one carcass ply 44. The carcass 12 of the tire 2 is made up of one carcass ply 44. The carcass ply 44 is turned up at each bead 10.

[0048] The carcass ply 44 includes a ply body 48 and a pair of turned-up portions 50. The ply body 48 spans between a pair of beads 10, i.e., between one bead 10 and the other bead 10 (not shown). Each turned-up portion 50 is continuous with the ply body 48 and turned up at the bead 10. The turned-up portions 50 of this tire 2 are turned up at the bead 10 from the inside to the outside in the axial direction. The turned-up portions 50 are turned up so that ends PF of the turned-up portions 50 are located axially outside the apex 38.

[0049] In the tire 2 according to this embodiment, the end PF of the turned-up portion 50 is located at a predetermined position. The specific position will be described later. In this tire 2, the bead 10 is sandwiched between the ply body 48 and the turned-up portion 50.

[0050] Although not shown in Figures 1 and 2, the carcass ply 44 includes a number of carcass cords arranged in parallel. These carcass cords are covered with a topping rubber. Each carcass cord crosses the equator plane. The material of these carcass cords is an organic fiber cord. Examples of the organic fiber include nylon fiber, polyester fiber, rayon fiber, and aramid fiber. In the tire 2, the carcass cord is an organic fiber cord, and therefore, the carcass cord is less likely to block the radio waves exchanged with the RFID tag 54.

[0051] As the organic fiber cord, a cord made of aramid fiber (hereinafter referred to as aramid cord) is preferred from the viewpoint of having durability and heat resistance similar to that of a steel cord. The aramid fiber that is the material of the aramid cord is preferably a para-aramid fiber. Therefore, the carcass cord used in the tire 2 is preferably a cord made of a para-aramid fiber (hereinafter referred to as a para-aramid cord).

[0052] 1, the length indicated by the symbol N is the radial distance from the bead base line to the end PF of the turned-up portion 50. The radial distance N is also called the radial height of the end PF of the turned-up portion 50. In the tire 2, the ratio (N / H) of the radial height N of the end PF of the turned-up portion 50 to the radial height H of the reference maximum width position PWb is equal to or greater than 0.20 and is equal to or less than 0.40.

[0053] Each cushion layer 14 is located at an end of the reinforcing layer 20 between the reinforcing layer 20 and the carcass 12. The cushion layer 14 is made of a soft crosslinked rubber.

[0054] Each steel filler 16 is located in the bead portion. The steel filler 16 is turned up around the core 36 from the axially inner side to the axially outer side along the carcass ply 44. The steel filler 16 is arranged so as to wrap around the radially inner portion of the bead 10 from the radially inner side of the turned-up portion 50.

[0055] Although not shown, the steel filler 16 includes a number of filler cords arranged in parallel. The filler cords are made of steel. The steel filler 16 includes steel cords. In the steel filler 16, the steel cords are covered with topping rubber.

[0056] The outer end 16f of the steel filler 16 is located axially outside the turned-up portion 50. The outer end 16f is located radially inside the end PF of the turned-up portion 50. The inner end 16s of the steel filler 16 is located axially inside the ply body 48. The radial position of the inner end 16s may be approximately the same as that of the outer end 16f, and the inner end 16s may be located radially outside or inside the outer end 16f.

[0057] The inner liner 18 is positioned inside the carcass 12. The inner liner 18 is joined to the inner surface of the carcass 12 via insulation (not shown) made of crosslinked rubber. The inner liner 18 forms the inner surface of the tire 2. The inner liner 18 is made of crosslinked rubber that has excellent air barrier properties.

[0058] The reinforcing layer 20 is located radially inside the tread 4. The reinforcing layer 20 is located between the carcass 12 and the tread 4. The reinforcing layer 20 includes a belt 62 and a band 70. The reinforcing layer 20 increases the rigidity of the tread portion.

[0059] The belt 62 includes a plurality of belt plies 64 arranged in the radial direction. Each belt ply 64 is arranged such that both ends thereof face each other across the equatorial plane. The belt 62 of the tire 2 includes four belt plies 64. The four belt plies 64 include a first belt ply 64A located on the inside in the radial direction, a second belt ply 64B located on the outside of the first belt ply 64A, a third belt ply 64C located on the outside of the second belt ply 64B, and a fourth belt ply 64D located on the outside of the third belt ply 64C.

[0060] In the tire 2, the second belt ply 64B has the widest axial width and the fourth belt ply 64D has the narrowest axial width. The first belt ply 64A and the third belt ply 64C have the same axial width, or the axial width of the first belt ply 64A is wider than the axial width of the third belt ply 64C.

[0061] The end 62e of the belt 62 of the tire 2 is represented by the end of the belt ply 64 having the widest axial width among the multiple belt plies 64 constituting the belt 62. In the tire 2, as described above, the second belt ply 64B has the widest axial width among the four belt plies 64 constituting the belt 62. The end 62e of the belt 62 of the tire 2 is represented by the end of the second belt ply 64B having the widest axial width.

[0062] 1, an end of the first belt ply 64A, an end of the second belt ply 64B, and an end of the third belt ply 64C are located outside the shoulder circumferential groove 28s in the axial direction, and an end of the fourth belt ply 64D is located inside the shoulder circumferential groove 28s in the axial direction.

[0063] In the tire 2, each belt ply 64 constituting the belt 62 includes a large number of belt cords arranged in parallel. The belt cords are covered with a topping rubber. The belt cords of the tire 2 are steel cords.

[0064] In the tire 2, the density of the belt cords in each belt ply 64 is 15 ends / 5 cm or more and 30 ends / 5 cm or less. The density of the belt cords is expressed by the number of cross sections of the belt cords included per 5 cm width of the belt ply 64 in a cross section of the belt ply 64 along a plane perpendicular to the extending direction of the belt cords.

[0065] The belt cords are inclined with respect to the circumferential direction in each belt ply 64. In the tire 2, the direction of inclination of the belt cords included in each belt ply 64 with respect to the circumferential direction (hereinafter referred to as the inclination direction of the belt cords) can be selected independently and arbitrarily for each belt ply 64. In the tire 2, from the viewpoint of ensuring a stable ground contact shape, it is preferable that the inclination direction of the belt cords of the second belt ply 64B is opposite to the inclination direction of the belt cords of the third belt ply 64C. The angle of inclination of the belt cords included in each belt ply 64 with respect to the circumferential direction is appropriately selected within a range of, for example, 10 degrees or more and 60 degrees or less.

[0066] The band 70 has two opposing ends 70e across the equator plane. The band 70 includes a spirally wound band cord. The band cord is covered with a topping rubber.

[0067] In the tire 2, the band cord is a steel cord or an organic fiber cord. Examples of the material of the organic fiber cord include nylon fiber, polyester fiber, rayon fiber, and aramid fiber. The band cord is preferably a steel cord.

[0068] As described above, the band 70 includes a spirally wound band cord. The band 70 has a jointless structure. In the band 70, the angle that the band cord forms with the circumferential direction of the tire 2 is preferably 5 degrees or less, and more preferably 2 degrees or less. The band cord of the band 70 extends substantially in the circumferential direction.

[0069] The density of the band cord in the band 70 is 20 ends / 5 cm or more and 35 ends / 5 cm or less. The density of the band cord is expressed by the number of cross sections of the band cord contained per 5 cm width of the band 70 in a cross section of the band 70 along a plane perpendicular to the extending direction of the band cord.

[0070] In the tire 2, an end of the second belt ply 64B and an end of the third belt ply 64C are each covered with a rubber layer 66. Two more rubber layers 66 are disposed between the end of the second belt ply 64B covered with the rubber layer 66 and the end of the third belt ply 64C. In the tire 2, an edge member 68 made of a total of four rubber layers 66 is configured between the end of the second belt ply 64B and the end of the third belt ply 64C. The edge member 68 is made of crosslinked rubber. The edge member 68 contributes to maintaining the gap between the end of the second belt ply 64B and the end of the third belt ply 64C. In the tire 2, changes in the positional relationship between the end of the second belt ply 64B and the end of the third belt ply 64C due to running are suppressed. The edge member 68 is part of the reinforcing layer 20. The reinforcing layer 20 of the tire 2 includes a pair of edge members 68 in addition to the belt 62 and the band 70.

[0071] As described above, the band 70 has two opposing ends 70e across the equatorial plane. The band 70 extends in the axial direction from the equatorial plane toward each end 70e. The ends 70e of the band 70 are located axially outward from the shoulder circumferential grooves 28s. The band 70 is located radially inward from the shoulder circumferential grooves 28s.

[0072] In this tire 2, the band 70 suppresses growth of the carcass 12 due to running, and suppresses changes in the shape of the tire 2. Therefore, it is possible to suppress an increase in distortion during running near the end PF of the folded-up portion 50 of the carcass 12. Therefore, durability is improved compared to a tire 2 not provided with the band 70.

[0073] In this tire 2, the end 70e of the band 70 is located inside the end 62e of the belt 62 in the axial direction. The belt 62 is wider than the band 70. The belt 62 restrains the end 70e of the band 70. The belt 62 contributes to suppressing tension fluctuations in the band cord included in the band 70. Since the occurrence of band cord breakage due to tension fluctuations is suppressed, the band 70 can stably exert its function of suppressing shape change. From this perspective, it is preferable that the end 70e of the band 70 is located inside the end 62e of the belt 62 in the axial direction.

[0074] A force acts on the band 70 of the tire 2 so as to expand from the inside to the outside in the radial direction. This force generates tension in the band cord of the band 70. In the tire 2, the second belt ply 64B is located radially inside the band 70, and the third belt ply 64C is located radially outside the band 70. In the tire 2, the band 70 is sandwiched between the second belt ply 64B and the third belt ply 64C. The second belt ply 64B is wider than the band 70. The third belt ply 64C is also wider than the band 70. The multiple belt plies 64 constituting the belt 62 of the tire 2 include two belt plies 64 having a width wider than the width of the band 70, and the band 70 is sandwiched between these two belt plies 64 having a wider width. In the tire 2, tension fluctuations in the band cords included in the band 70 are more effectively suppressed, so breakage is less likely to occur in the band cords of the band 70. The band 70 of the tire 2 can stably exhibit its function of suppressing shape deformation. From this viewpoint, in the tire 2, it is preferable that the plurality of belt plies 64 constituting the belt 62 include two belt plies 64 having a width wider than the width of the band 70, and that the band 70 is sandwiched between these two belt plies 64 having a wider width.

[0075] In the tire 2, the first belt ply 64A, the second belt ply 64B, and the third belt ply 64C have a width greater than the width of the band 70. The first belt ply 64A and the second belt ply 64B are located inside the band 70, and the third belt ply 64C and the fourth belt ply 64D are located outside the band 70 in the radial direction.

[0076] The tag member 26 is located axially outward of the bead 10. In this tire 2, the tag member 26 is provided only on one side of the sidewall 6. The tag member 26 may be provided on both one side of the sidewall 6 and the other sidewall 6. From the viewpoint of reducing the risk of damage, it is preferable that the tag member 26 be provided only on one side of the pair of sidewalls 6.

[0077] Fig. 3 is a plan view of the tag member 26. Fig. 4 is a cross-sectional view taken along line IV-IV in Fig. 3. The tag member 26 has a plate shape. The tag member 26 is long in the length direction and short in the width direction. As shown in FIG. 1 , the tag member 26 is disposed in the tire 2 such that a first end 26s in the width direction thereof is located on the radially outer side of the tire 2 and a second end 26u is located on the inner side. In this tire 2, the first end 26s is also referred to as the outer end, and the second end 26u is also referred to as the inner end.

[0078] The tag member 26 includes an RFID tag 54. In FIG. 3, the RFID tag 54 is shown with a solid line for ease of explanation, and is entirely covered with a protective body 56. The tag member 26 includes the RFID tag 54 and the protective body 56. The RFID tag 54 is located at the center of the tag member 26. The protective body 56 is made of cross-linked rubber. The protective body 56 has approximately the same rigidity as the outer apex 42. In this tire 2, the formation of a good communication environment is taken into consideration, and a cross-linked rubber with high electrical resistance is used for the protective body 56. The protective body 56 is made of rubber with high insulating properties.

[0079] Although not described in detail, the RFID tag 54 is a small, lightweight electronic component consisting of a semiconductor chip 58 that integrates a transmitter / receiver circuit, a control circuit, memory, etc., and an antenna 60. When the RFID tag 54 receives an interrogation signal, it uses the received signal as electrical energy and transmits the data stored in its memory as a response signal. This RFID tag 54 is a type of passive radio frequency identification transponder.

[0080] In the RFID tag 54, the antenna 60 extends from the semiconductor chip 58 in the length direction of the RFID tag 54 (left and right direction in FIG. 3). As shown in FIG. 3, the RFID tag 54 includes a pair of antennas 60 extending in the length direction thereof, and the semiconductor chip 58 located between the pair of antennas 60. The RFID tag 54 is arranged in the tag member 26 such that the length direction of the RFID tag 54 coincides with the length direction of the tag member 26. 3 is just an example, and the antenna 60 constituting the RFID tag 54 may have various shapes. The shape of the antenna 60 may be, for example, a shape that extends while bending, a spiral shape, or the like.

[0081] In the embodiment of the present invention, the external dimensions (length, width, and thickness) of the RFID tag 54 are represented by the length, width, and thickness of a circumscribing rectangular parallelepiped of the RFID tag 54. The length of the RFID tag 54 is equal to or greater than the width of the RFID tag 54. The width of the RFID tag 54 is equal to or greater than the thickness of the RFID tag 54. In the embodiment of the present invention, the length direction of the RFID tag 54 is also the length direction of the antenna 60 that constitutes the RFID tag 54. In other words, the length direction of the antenna 60 is the length direction of the RFID tag 54.

[0082] The tag member 26 is a plate-shaped member in which the RFID tag 54 is covered with cross-linked rubber (protector). From the viewpoints of reducing the risk of damage to the RFID tag 54 and creating a good communication environment, the thickness of the tag member 26 in the tire 2 is preferably 1.0 mm or more and 2.5 mm or less. The thickness of the tag member 26 in the tire 2 is represented by the maximum thickness of the tag member 26 in the semiconductor chip 58 of the RFID tag 54. The length TL of the tag member 26 before being embedded in the tire 2 is, for example, 60 mm or more and 80 mm or less, and the width TW is, for example, 10 mm or more and 20 mm or less.

[0083] Fig. 5 shows a portion of a meridian cross section of a tire 2 in a ground contact state. The cross section in Fig. 5 is a trace of a cross-sectional image of the tire 2 taken by, for example, computed tomography using X-rays (hereinafter referred to as X-ray CT) when a load of 50% of the normal load is applied to the tire 2 in a normal state and the tire 2 is brought into contact with a flat surface FS. In the present invention, a state in which a load of 50% of the normal load is applied to the tire 2 in the normal state and the tire 2 is brought into contact with the plane FS is also called the standard contact state. In the standard contact state shown in Figure 5, the tire camber angle is set to 0 degrees.

[0084] 5, the position indicated by the symbol PRa is the axially outer end of the flange Rf of the rim R. The dashed dotted line indicated by the symbol LRa is a straight line that passes through the axially outer end PRa and extends radially. The position indicated by the symbol PRr is the radially outer end of the flange Rf. The dashed dotted line indicated by the symbol LRr is a straight line that passes through the radially outer end PRr and extends in the axial direction. 5, the position indicated by the symbol PWs is the maximum width position of the tire 2 in a standard contact state. The dashed dotted line indicated by the symbol LWsa is a straight line that passes through the maximum width position PWs and extends in the radial direction. The dashed dotted line indicated by the symbol LWsr is a straight line that passes through the maximum width position PWs and extends in the axial direction. 5, the tire 2 is shown in a simplified manner, and some of the elements of the tire 2 shown in FIG. 1, such as the reinforcing layer 20, are omitted.

[0085] As shown in Fig. 5, in the tire 2 in the standard contact state, the RFID tag 54 is located radially outward from the radially outer end PRr of the rim R. Therefore, radio waves are not blocked by the rim R, and the performance of reading data from the RFID tag is good. In the standard contact state, the RFID tag 54 is preferably located radially inward from the maximum width position PWs of the tire 2. In this case, the RFID tag 54 is located in a position that is less likely to bend during running, so the RFID tag 54 itself is less likely to be damaged, and damage to the tire 2 originating from the location of the RFID tag 54 is also less likely to occur.

[0086] In the present invention, the RFID tag 54 being located outside the radial outer end PRr of the rim R means that the entire semiconductor chip 58 of the RFID tag 54 is located outside the radial outer end PRr of the rim R. In addition, the RFID tag 54 being located inside the maximum width position PWs of the tire 2 means that the entire semiconductor chip 58 of the RFID tag 54 is located inside the maximum width position PWs of the tire 2.

[0087] Furthermore, in the tire 2 in the standard ground contact state, the RFID tag 54 is located axially outward from the axial outer end PRa of the rim R, and the end PF of the folded-back portion 50 is located axially inward from the axial outer end PRa of the rim R. In this case, the RFID tag 54 and the end PF of the folded-back portion 50 are positioned apart from each other in the axial direction. This makes it possible to suppress an increase in distortion near the end PF of the folded-back portion 50, which may occur due to the presence of the RFID tag 54, a foreign object to the tire, in proximity. In the present invention, the RFID tag 54 being located outside the axial outer end PRa of the rim R means that the entire semiconductor chip 58 of the RFID tag 54 is located outside the axial outer end PRa of the rim R.

[0088] From the above viewpoints, the preferred attachment position of the tag member 26 attached to the tire 2 is a position within the regions surrounded by the dashed-dotted lines LWsr and LWsa, and the dashed-dotted lines LRr and LRa in the standard grounding state, where the entire semiconductor chip 58 of the RFID tag 54 is included.

[0089] Furthermore, in this tire 2, the RFID tag 54 is arranged at a distance from the vicinity of the end of the flange Rf and the vicinity of the maximum width position PWs where large distortion may occur if the RFID tag 54 is present. In this tire 2, it is suppressed that the presence of the RFID tag 54 promotes an increase in distortion. In this tire 2, the occurrence of damage caused by the presence of the RFID tag 54 is suppressed. Moreover, damage to the RFID tag 54 itself is also suppressed. In this tire 2, good durability is maintained even though the RFID tag 54 is built-in.

[0090] In FIG. 5, the double-headed arrow LA is the axial distance between the end PF of the folded-back portion 50 and the outer axial end PRa of the rim R. The double-headed arrow LB is the axial distance between the RFID tag 54 and the outer axial end PRa of the rim R. Here, the axial distance LB between the RFID tag 54 and the outer axial end PRa of the rim R refers to the shortest distance in the axial direction between the semiconductor chip 58 of the RFID tag 54 and the outer axial end PRa of the rim R.

[0091] In the tire 2, it is preferable that the axial distance LA and the axial distance LB satisfy LA < LB. As already explained, in order to suppress an increase in distortion near the end PF of the folded-back portion 50 while ensuring the reading performance of the RFID tag 54, the axial distance between the end PF of the folded-back portion 50 and the RFID tag 54 is preferably larger. However, from the viewpoint of more easily ensuring the reading performance of the RFID tag 54, it is more preferable that the RFID tag 54 is further away from the rim R in the axial direction. From the above viewpoints, the axial distance LB is more preferably 1.5 times or more and 8.0 times or less of the axial distance LA.

[0092] In the tire 2, in the standard contact state shown in FIG. 5, the edge PE of the tread surface 24 is located axially outward from the dashed line indicated by the symbol LRa. In the tire 2, in the standard ground contact state shown in FIG. 5, the outer end PU of the inner apex 40 is located axially inward of the dashed line indicated by the symbol LRa.

[0093] Fig. 6 is a diagram illustrating the angle formed between the length direction of the RFID tag and the carcass cord. Fig. 6 is a diagram illustrating the positional relationship between the RFID tag and the carcass cord when a portion of the tire 2 is viewed along the axial direction. Therefore, in Fig. 6, the direction penetrating the paper is the axial direction of the tire 2. The acute angle is used as the angle formed between the length direction of the RFID tag and the carcass cord, except when this angle is 90 degrees. The RFID tag is attached in a predetermined direction to the tire 2. Specifically, the angle θ formed between the carcass cord 46 included in the carcass 12 and the longitudinal direction of the RFID tag 54 is equal to or greater than 80 degrees and equal to or less than 90 degrees.

[0094] In the tire 2, organic fiber cords are used as the carcass cords 46. The sidewall portions of a tire using organic fiber cords as the carcass cords 46 are more susceptible to bending than tires using steel cords as the carcass cords. Therefore, when an RFID tag 54 is attached to a tire using organic fiber cords as the carcass cords, depending on the orientation of the RFID tag 54, the RFID tag 54 may be significantly affected by the bending of the sidewall portions and may be more susceptible to damage. Under such circumstances, if the RFID tag 54 is arranged so that the angle between its length direction and the carcass cord 46 approaches 90 degrees, the influence of the above-mentioned bending on the RFID tag 54 can be reduced. Therefore, in the tire 2, the angle θ formed between the length direction of the RFID tag 54 and the carcass cord 46 is set to be equal to or greater than 80 degrees and equal to or less than 90 degrees. The angle θ is preferably as close to 90 degrees as possible.

[0095] Here, the above θ means the angle between the length direction of the RFID tag 54 and the carcass cord 46A closest to the center of the semiconductor chip 58 of the RFID tag 54 when the tire 2 is viewed in the axial direction. Moreover, the center of the semiconductor chip 58 when the tire 2 is viewed in the axial direction means the center of the circumscribing rectangle of the semiconductor chip 58 when viewed in the axial direction (the intersection of the diagonals of the circumscribing rectangle).

[0096] 1, the length indicated by the double-headed arrow t is the shortest distance from the outer surface of the tire 2 to the RFID tag 54. The shortest distance t is the thickness of the rubber covering the RFID tag 54.

[0097] In this tire 2, the shortest distance t is preferably 3.5 mm or more. This allows the RFID tag 54 to be covered with rubber having a sufficient thickness. In this tire 2, the presence of the RFID tag 54 is effectively prevented from contributing to an increase in distortion. In this tire 2, the occurrence of damage caused by the presence of the RFID tag 54 is effectively prevented. From this perspective, the shortest distance t is more preferably 4.0 mm or more. Note that the upper limit of this shortest distance t varies depending on the position of the RFID tag 54, so no preferred upper limit is set for the shortest distance t.

[0098] In the tire 2, the tag member 26 is preferably located radially outward of the end PF of the turned-up portion 50 and axially outward of the outer apex 42. In this case, the tag member 26 contacts the outer apex 42. The boundary between the tag member 26 and the outer apex 42 forms part of the outer surface of the outer apex 42. In other words, the boundary between the tag member 26 and the outer apex 42 forms part of the outer surface of the apex 38. In the tire 2, the RFID tag 54 is located between the outer end PG2 of the outer apex 42 and the end PF of the folded-back portion 50 in the radial direction. The RFID tag 54 of this tire 2 is placed in a bead portion where the degree of bending is small. In this tire 2, the risk of damage to the RFID tag 54 is low.

[0099] In this tire 2, the outer apex 42, which is softer than the inner apex 40, is located axially inside of the RFID tag 54, and therefore the presence of the RFID tag 54 is effectively prevented from promoting an increase in distortion. In this tire 2, the occurrence of damage caused by the presence of the RFID tag 54 is prevented. Moreover, the occurrence of damage to the RFID tag 54 itself is also prevented. In this tire 2, good durability is maintained despite the inclusion of the RFID tag 54.

[0100] From the viewpoint of maintaining good durability while forming a good communication environment and reducing the risk of damage to the RFID tag 54, it is preferable that the tag member 26 contacts the outer apex 42 radially outside the end PF of the folded portion 50, and that the RFID tag 54 is located radially between the outer end PG2 of the outer apex 42 and the end PF of the folded portion 50. From the same viewpoint, it is more preferable that the RFID tag 54 be located radially between the outer end PG2 of the outer apex 42 and the outer end PB of the chafer 8.

[0101] In this tire 2, it is preferable that the entire tag member 26 is disposed radially outward of the outer end PB of the chafer 8. Interference of the tag member 26 with the outer end PB of the chafer 8 is effectively suppressed, thereby effectively suppressing waving of the outer end PB of the chafer 8 (i.e., the occurrence of creases). The presence of the RFID tag 54 is effectively suppressed from contributing to an increase in distortion. In this tire 2, the occurrence of damage due to the presence of the RFID tag 54 is suppressed. Moreover, damage to the RFID tag 54 itself is also suppressed. In this tire 2, good durability is maintained despite the incorporation of the RFID tag 54.

[0102] In the tire 2, it is preferable that the entire tag member 26 be located radially inward of the outer end PG2 of the outer apex 42. This effectively suppresses the influence of the tag member 26 on the deflection of the sidewall portion. In the tire 2, good durability and ride comfort are maintained. From this viewpoint, it is preferable that the outer end 26s of the tag member 26 be located radially inward of the outer end PG2 of the outer apex 42.

[0103] In the tire 2, it is preferable that the outer end PU of the inner apex 40 be located between the end PF of the turned-up portion 50 and the RFID tag 54 in the radial direction. This allows the hard inner apex 40 to effectively increase the rigidity of the bead portion. This effectively reduces distortion acting on the RFID tag 54. The presence of the RFID tag 54 is effectively prevented from contributing to an increase in distortion. From this perspective, it is preferable that the outer end PU of the inner apex 40 be located between the end PF of the turned-up portion 50 and the RFID tag 54 in the radial direction. In this case, from the perspective of more effectively preventing the presence of the RFID tag 54 from contributing to an increase in distortion, it is more preferable that the outer end PU of the inner apex 40 be located between the end PF of the turned-up portion 50 and the RFID tag 54 in the radial direction, and that the outer end PU of the inner apex 40 be located between the end PF of the turned-up portion 50 and the RFID tag 54 in the radial direction.

[0104] The bead portion of the tire 2 described so far is a heavy-duty tire in which the end PF of the folded portion 50 is located axially outside the apex 38, but in the heavy-duty tire according to the embodiment of the present invention, the structure of the bead portion is not limited to such a structure. FIG. 7 is a cross-sectional view showing a part of a heavy-duty tire 102 (hereinafter referred to as tire 102) according to another embodiment of the present invention. This tire 102 has a similar configuration to tire 2, except that the positions of the ends of the turned-up portions of the carcass ply in the bead portions are different. In Figure 7, the same reference numerals as in Figure 2 are used for elements other than the carcass ply 144 and the beads 110.

[0105] 7, the turned-up portion 150 of the carcass ply 144 is wound approximately one full turn around the core 136 while being turned back radially inside the bead 110 from the axially inner side toward the axially outer side, and has a structure (sometimes called a bead-wound structure) in which an end RF2 of the turned-up portion 150 aligned with a radially upper surface 136j of the core 136 is sandwiched between the core 136 and the apex 138. In this tire 102, the apex 138 has an inner apex 140 and an outer apex 142, and the end RF2 of the turned-up portion 150 is sandwiched between the radially upper surface 136j of the core 136 (wrapping layer 136r) and the inner apex 140. In FIG. 7, 136m is a core body, and 148 is a ply body.

[0106] In the tire 102, the end RF2 of the turned-up portion 150 is sandwiched between the core and the inner apex, which are harder than the outer apex and the chafer. Therefore, in the tire 102, distortion near the end RF2 of the turned-up portion 150 is particularly unlikely to occur.

[0107] Furthermore, the tire 102 employs organic fiber cords, which are more flexible than steel cords, as carcass cords. Therefore, the tire 102 is less susceptible to strong unbending (so-called springback) at folded-up portions during the green tire building process, which is likely to occur when steel cords are employed as carcass cords in a tire having a bead-wound structure. The tire 102 employing organic fiber cords as the carcass cords is less likely to experience the above-mentioned springback, and is therefore less likely to suffer from molding defects such as cavities in the bead portions during the green tire molding process.

[0108] In the tire 102, the tag member 26 having the RFID tag 54 is attached to a predetermined position, similar to the tire 2. Therefore, the tire 102 is also a heavy-duty tire with good performance in reading data from the RFID tag and good durability.

[0109] In the tire 102, the core 136 may be further covered with a vulcanized rubber layer around the wrapping layer 136r.

[0110] As is clear from the above description, according to the present invention, a heavy-duty tire 2 can be obtained that has good performance in reading data from an RFID tag and good durability. [Industrial Applicability]

[0111] The techniques described above can be applied to attaching RFID tags to various tires.

[0112] [Note] The present invention includes the following aspects.

[0113] [1] Tread and a pair of sidewalls connected to the ends of the tread and positioned radially inward of the tread; a pair of beads located radially inside the sidewall; a carcass located inside the tread and the pair of sidewalls and spanning between one bead and the other bead; a belt laminated on the carcass on a radially inner side of the tread; a pair of chafers located radially inside the sidewalls and in contact with the rim; A tire comprising a tag member including an RFID tag, The bead includes a core and an apex located radially outward of the core, The carcass includes a carcass ply including a plurality of carcass cords arranged in parallel, the carcass cord is made of organic fiber, The carcass ply includes a ply body that spans between the pair of beads, and a pair of turn-up portions that are connected to the ply body and turned up at the beads, The rim is a regular rim, The state in which the tire is mounted on the rim and the internal pressure of the tire is adjusted to a normal internal pressure is the normal state, A state in which a load of 50% of the normal load is applied to the tire in the normal state and the tire is brought into contact with a flat surface is the standard contact state, In the standard ground contact state, an end of the folded-up portion is located axially inward from an axially outer end of the rim, In the standard grounding state, the RFID tag is located axially outward from an axially outer end of the rim, and radially outward from a radially outer end of the rim; A heavy-duty tire, wherein the angle between the length direction of the RFID tag and the carcass cord is 80 degrees or more and 90 degrees or less.

[0114] [2] The heavy-duty tire according to the above-mentioned [1], wherein the carcass cord is made of aramid fiber.

[0115] [3] The heavy-duty tire according to [1] or [2] above, wherein, in the standard ground contact state, the RFID tag is located radially inward from the maximum width position of the tire.

[0116] [4] The heavy-duty tire according to any one of [1] to [3] above, further comprising a band positioned between the tread and the belt in the radial direction and having opposite ends across the equatorial plane.

[0117] [5] The heavy-duty tire according to any one of the above-mentioned [1] to [4], wherein an end of the folded-up portion is sandwiched between the core and the apex.

[0118] [6] An end of the folded portion is located axially outward of the apex, The heavy-duty tire according to any one of the above-mentioned [1] to [4], wherein the axial distance LB between the RFID tag and the axial outer end of the rim in the standard contact state is longer than the axial distance LA between the end of the folded-back portion and the axial outer end of the rim in the standard contact state. [Explanation of symbols]

[0119] 2, 102... Tires 4. Tread 6. Sidewall 8. Chafer 10, 110... beads 12. Carcass 14. Cushion layer 16···Steel filler 18···Inner liner 20. Reinforcement layer 24 Tread surface 26 Tag member 28...Circumferential groove 30... Rikubu 36, 136···core 38, 138···Apex 40, 140... Inner apex 42, 142...Outer apex 44, 144... Carcass ply 46···Carcass cord 48, 148... Ply body 50, 150... Folded section 54... RFID tags 56 Protective body 58. Semiconductor chip 60...antenna 62 Belt 64 Belt ply 66 Rubber layer 68 Edge member 70...Band

Claims

1. Tread and a pair of sidewalls connected to the ends of the tread and positioned radially inward of the tread; a pair of beads located radially inside the sidewall; a carcass located inside the tread and the pair of sidewalls and spanning between one bead and the other bead; a belt laminated on the carcass on a radially inner side of the tread; a pair of chafers located radially inside the sidewalls and in contact with the rim; A tire comprising: a tag member including an RFID tag, The bead includes a core and an apex located radially outward of the core, The carcass includes a carcass ply including a plurality of carcass cords arranged in parallel, the carcass cord is made of organic fiber, The carcass ply includes a ply body that spans between the pair of beads, and a pair of turn-up portions that are connected to the ply body and turned up at the beads, The rim is a regular rim, The state in which the tire is mounted on the rim and the internal pressure of the tire is adjusted to a normal internal pressure is the normal state, A standard contact state is a state in which a load of 50% of a normal load is applied to the tire in the normal state and the tire is brought into contact with a flat surface, In the standard ground contact state, an end of the folded-up portion is located axially inward from an axially outer end of the rim, In the standard grounding state, the RFID tag is located axially outward from an axially outer end of the rim, and radially outward from a radially outer end of the rim; A heavy-duty tire, wherein the angle formed between the length direction of the RFID tag and the carcass cord is 80 degrees or more and 90 degrees or less.

2. 2. The heavy duty tire according to claim 1, wherein the carcass cords are made of aramid fibers.

3. 3. The heavy-duty tire according to claim 1, wherein, in the standard ground contact state, the RFID tag is positioned radially inward from a maximum width position of the tire.

4. 3. The heavy-duty tire according to claim 1, further comprising a band positioned between the tread and the belt in the radial direction and having opposite ends across an equatorial plane.

5. The heavy-duty tire according to claim 1 or 2, wherein an end of the turned-up portion is sandwiched between the core and the apex.

6. an end of the folded portion is located axially outward of the apex; 3. The heavy-duty tire according to claim 1, wherein an axial distance LB between the RFID tag and the axial outer end of the rim in the standard ground contact state is longer than an axial distance LA between the end of the folded-back portion and the axial outer end of the rim in the standard ground contact state.

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