Bias tire

Abstract

To provide a bias tire 2 capable of suppressing a deterioration in durability due to incorporation of an RFID tag while constructing a satisfactory communication environment.SOLUTION: A bias time 2 includes a pair of beads 8, a carcass 10, a tread 4, a pair of sidewalls 6, and a tag member 12 including an RFID tag 32. A protrusion part 48 is disposed at a part including a boundary between the tread 4 and the sidewalls 6. The carcass 10 includes a carcass body 44 and a carcass jacket 46. The carcass body 44 includes at least two winding plies 40. The carcass jacket 46 includes at least one sheet of a hanger ply 42. The tag member 12 is laminated outside the carcass jacket 46 at a part with the protrusion part 48 disposed. The RFID tag 32 does not overlap an end 40te of a folding part 40t of each winding ply 40 in the thickness direction of the bias tire 2.SELECTED DRAWING: Figure 6

Description

[Technical field]

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

[0002] The incorporation of Radio Frequency Identification (RFID) tags into tires is being considered in order to manage data such as tire manufacturing management, customer information, and driving history. There are various types of tires, such as tires for trucks and buses, tires for passenger cars, etc. Patent Document 1 below discloses a safety tire as a passenger car tire with a built-in RFID tag. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2021-116027 A Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present invention is to provide a bias tire that can suppress a decrease in durability caused by incorporating an RFID tag while creating a good communication environment. [Means for solving the problem]

[0005] The bias tire according to the present invention is a bias tire having a nominal aspect ratio of 85% or less. The bias tire includes a pair of beads, a carcass spanning between the pair of beads, a tread located radially outward of the carcass and in contact with a road surface, a pair of sidewalls connected to the ends of the tread and located axially outward of the carcass, and a tag member including an RFID tag. A convex portion is provided in a portion including a boundary between the tread and the sidewall. In a meridian cross section of the bias tire, the convex portion has an extension along a side surface of the bias tire. The carcass is composed of at least three carcass plies including a large number of carcass cords arranged in parallel. In each of the carcass plies, each carcass cord is inclined with respect to the equatorial plane. The carcass includes a carcass body and a carcass jacket covering the carcass body from the outside. The carcass body includes at least two of the carcass plies, and the at least two carcass plies are wound plies folded back at each of the beads. Each of the wound-up plies includes a ply body and a pair of turn-up portions. The ply body spans between the pair of beads. Each of the pair of turn-up portions is connected to the ply body and turned up at the bead. A plurality of the turn-up portions are arranged in the axial direction on the axial outside of each of the beads. Between two adjacent turn-up portions among the plurality of turn-up portions, an end of one turn-up portion is located radially outside an end of the other turn-up portion. The carcass jacket includes at least one of the carcass plies, and the at least one carcass ply is a hanger ply that is not turned up at each of the beads. The tag member is laminated on the outside of the carcass jacket in a portion where the protrusion is provided. The RFID tag does not overlap with the ends of each of the turn-up portions in the thickness direction of the bias tire. Effect of the Invention

[0006] According to the present invention, a bias tire can be obtained that can suppress a decrease in durability caused by incorporating an RFID tag while establishing a good communication environment. [Brief description of the drawings]

[0007] [Figure 1] FIG. 2 is a cross-sectional view showing a portion of a bias tire. [Diagram 2] FIG. 2 is a cross-sectional view showing a portion of the tire of FIG. [Diagram 3] FIG. 2 is a schematic diagram illustrating a configuration of a carcass. [Figure 4] FIG. [Diagram 5] FIG. 5 is a cross-sectional view taken along line VV in FIG. [Figure 6] FIG. 2 is a cross-sectional view showing a portion of the tire of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] The tire of the present invention is mounted on a rim. Air is filled inside the tire, and the internal pressure of the tire is adjusted. The tire mounted on the rim is also called a tire-rim assembly. The tire-rim assembly includes a rim and a tire mounted on the rim.

[0009] 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 called a standard state.

[0010] 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 in the meridian section of the tire, which cannot be measured when the tire is mounted on a regular rim, are measured on the cut surface of the tire obtained by cutting the tire along a plane including the axis of rotation. In this measurement, the tire is set so that the distance between the left and right beads is the same as the distance between the beads of the tire mounted on a regular rim. The tire configuration that cannot be confirmed when the tire is mounted on a regular rim is confirmed on the aforementioned cut surface.

[0011] A genuine rim is a rim that is 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 genuine rims.

[0012] Normal tire pressure means the internal pressure specified in the standard on which the tire is based. The "maximum air pressure" in the JATMA standard, the "maximum value" listed in "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES" in the TRA standard, and the "INFLATION PRESSURE" in the ETRTO standard are normal tire pressures.

[0013] 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 "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES" in the TRA standard, and the "LOAD CAPACITY" in the ETRTO standard are normal loads.

[0014] In the present invention, the tread portion of a tire is the portion of the tire that comes into contact with the road surface. The bead portion is the portion of the tire that fits onto the rim. The sidewall portion is the portion of the tire that bridges between the tread portion and the bead portion. A tire has the following portions: a tread portion, a pair of bead portions, and a pair of sidewall portions. The portion consisting of the bead portion and the sidewall portion is also called a side portion. The boundary portion between the tread portion and the sidewall portion is also called a buttress.

[0015] In the present invention, the term "thickness direction of the tire" means a direction along a normal to the inner surface of the tire.

[0016] In the present invention, the "nominal aspect ratio" is the "nominal aspect ratio" included in the "tire designation" defined in JIS D4202 "Automobile tires - designation and specifications". In this specification, the "nominal aspect ratio" means the "nominal aspect ratio" unless otherwise specified.

[0017] [Foundations underlying the present invention] The tire carcass includes a number of parallel carcass cords. Each carcass cord spans between a pair of beads. The carcass cords cross the equator plane. Tire carcasses include radial carcasses and bias carcasses. In the radial structure, the crossing angle of the carcass cords is set in the range of 70 to 90 degrees. The carcass cords cross the equatorial plane almost perpendicularly. In the side portions of the tire, the carcass cords extend in the approximate radial direction of the tire. Therefore, for example, even if the carcass is composed of two carcass plies, the carcass cords included in one carcass ply and the carcass cords included in the other carcass ply do not constrain each other. In the radial structure, the side portions are less likely to deform in response to deformation of the tread portion. In contrast, in a bias structure, the carcass cords cross obliquely with respect to the equatorial plane. In the side portion of the tire, the carcass cords are inclined with respect to the radial direction of the tire. Therefore, for example, if a carcass is made up of two carcass plies with carcass cords with different inclination directions, the carcass cords in one carcass ply cross the carcass cords in the other carcass ply, so that the carcass cords of one carcass ply and the carcass cords of the other carcass ply are restrained by each other. The rigidity of the side portion is higher than that of a radial structure. However, if the tread portion deforms, the radially outer portion of the side portion also deforms. In the case of bias-structure tires (hereafter referred to as "bias tires"), deformation is more widespread than in the case of radial-structure tires (hereafter referred to as "radial tires"). Therefore, if RFID tags are placed in the same way as in radial tires, there is a risk that durability will be compromised. When the carcass includes multiple wraparound plies, the side portion of the tire includes multiple turned-up ends. The side portion of a bias tire having an aspect ratio of 85% or less (hereinafter also referred to as a low-profile bias tire) is shorter than that of a normal bias tire having an aspect ratio of 100%. Therefore, in a low-profile bias tire, the distance between the ends of the turned-up portions is narrower than that of a normal bias tire. In the case of a low-profile bias tire, it is difficult to place an RFID tag while avoiding the ends of the turned-up portions. There are concerns that placing an RFID tag near metal elements such as the rim or bead core could disrupt the radio waves, and because the sidewalls of low-profile bias tires are short, the RFID tag is more susceptible to interference from metal elements. Therefore, in order to obtain a bias tire that can suppress the decrease in durability caused by the incorporation of an RFID tag while creating a good communication environment, the inventors took into consideration the characteristics of a carcass with a bias structure and studied the location of the incorporation of the RFID tag, and have completed the invention described below.

[0018] [Overview of the embodiment of the present invention] [Configuration 1] A bias tire according to one aspect of the present invention is a bias tire having a nominal aspect ratio of 85% or less, comprising a pair of beads, a carcass spanning between the pair of beads, a tread located radially outward of the carcass and in contact with a road surface, a pair of sidewalls connected to ends of the tread and located axially outward of the carcass, and a tag member including an RFID tag, wherein a protrusion is provided in a portion including a boundary between the tread and the sidewall, and in a meridian cross section of the bias tire, the protrusion is provided on a side surface of the bias tire. the carcass is composed of at least three carcass plies including a large number of carcass cords arranged in parallel, in each of the carcass plies, each carcass cord is inclined with respect to the equatorial plane, the carcass includes a carcass body and a carcass jacket that covers the carcass body from the outside, the carcass body includes at least two of the carcass plies, the at least two carcass plies are turn-up plies that are turned up at each of the beads, and each of the turn-up plies includes a ply body and a pair of turn-up portions, The ply body spans between a pair of the beads, a pair of the turn-up portions are each connected to the ply body and folded back at the beads, a plurality of the turn-up portions are arranged in the axial direction on the axial outside of each of the beads, and between two adjacent turn-up portions among the plurality of the turn-up portions, an end of one of the turn-up portions is located radially outside the end of the other turn-up portion, the carcass jacket includes at least one of the carcass plies, and the at least one of the carcass plies is a hanger ply that is not folded back at each of the beads, the tag member is laminated on the outside of the carcass jacket in a portion where the convex portion is provided, and the RFID tag does not overlap with the ends of each of the turn-up portions in the thickness direction of the bias tire.

[0019] By arranging the bias tires in this way, the decrease in durability caused by incorporating RFID tags is suppressed.

[0020] [Configuration 2] Preferably, in the bias tire according to the above-mentioned [Configuration 1], the carcass cord included in the hanger ply is a cord made of an organic fiber.

[0021] [Configuration 3] Preferably, in the bias tire described in the above-mentioned [Configuration 1] or [Configuration 2], the convex portion includes a boundary between the tread and the sidewall, and the RFID tag is positioned radially inward of and away from the boundary.

[0022] [Configuration 4] Preferably, in the bias tire described in any one of the above-mentioned [Configuration 1] to [Configuration 3], the convex portion is composed of a circumferentially continuous convex stripe or a plurality of blocks arranged in the circumferential direction, and when the convex portion is composed of a circumferentially continuous convex stripe, the RFID tag overlaps with the convex stripe in the thickness direction of the bias tire, and when the convex portion is composed of a plurality of blocks arranged in the circumferential direction, the RFID tag overlaps with a block adjacent to the RFID tag in the thickness direction of the bias tire.

[0023] [Configuration 5] Preferably, the bias tire according to any one of the above-mentioned [Configuration 1] to [Configuration 4] is an industrial vehicle tire.

[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.

[0025] 1 shows a part of a bias tire 2 (hereinafter, referred to as tire 2) according to one embodiment of the present invention. This tire 2 is mounted on an industrial vehicle such as a forklift. The aspect ratio of this tire 2 is 80%. When a bias tire having an aspect ratio of 100% is considered to be a normal bias tire, the aspect ratio of this tire 2 is lower than that of the normal bias tire. This tire 2 is a low aspect bias tire. In the present invention, a bias tire having a nominal aspect ratio of 85% or less is also called a low aspect bias tire.

[0026] FIG. 1 shows a portion of a cross section of a tire 2 taken along a plane including the rotation axis (not shown) of the tire 2. The cross section shown in FIG. 1 is also called a meridian cross section. The direction indicated by the double arrow AD is the axial direction of the tire 2. The axial direction of the tire 2 means a direction parallel to the rotation axis of the tire 2. The direction indicated by the double arrow RD 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. In FIG. 1, a dashed dotted line CL extending in the radial direction represents the equatorial plane of the tire 2. The cross section shown in Fig. 2 is a part of the meridian cross section shown in Fig. 1. Fig. 2 shows a part of the sidewall portion and the bead portion. In Fig. 2, the solid line BBL extending in the axial direction is the 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 is mounted on a rim R. The inside of the tire 2 is filled with air, for example, and the internal pressure is adjusted. Although not described in detail, the rim R is a regular rim. Although not shown, a tube is inserted inside the tire 2, and the inside of the tube is filled with air. The tire 2 is a tube type. The tire 2 may be a tubeless type.

[0028] The tire 2 includes a tread 4 , a pair of sidewalls 6 , a pair of beads 8 , a carcass 10 , and a tag member 12 .

[0029] The tread 4 is located radially outside the carcass 10. The tread 4 extends in the circumferential direction. The tire 2 comes into contact with the road surface at a tread surface 14. The outer surface of the tread 4 includes the tread surface 14 that comes into contact with the road surface. The outer surface 2G of the tire 2 includes the tread surface 14. 1, the position indicated by the symbol PC is the intersection point between the tread surface 14 and the equatorial plane. The intersection point PC is also called the equator of the tire 2. The tread surface 14 includes the equator PC. The tread 4 is made of crosslinked rubber. Of the tread 4, a portion including a tread surface 14 is made of crosslinked rubber in consideration of grip performance. The tread 4 is a main element of the tread portion. Although not described in detail, the tread 4 is made of a cross-linked rubber that is generally used as a cross-linked rubber for the tread of a bias tire. The position indicated by the symbol RN in FIG. 2 is the radially inner end of the tread 4 .

[0030] Although not described in detail, a plurality of lug grooves 18 are formed in the tread 4 of the tire 2. The tread 4 includes a plurality of lug grooves 18. Each of the lug grooves 18 extends from the equatorial plane side toward the outside in the axial direction. The lug grooves 18 are also called lateral grooves. Although not shown, the tread 4 of the tire 2 is formed with two lug groove row 20 in which a plurality of lug grooves 18 are arranged in the circumferential direction. One lug groove row 20 (hereinafter, first lug groove row 20a) is formed in a region on the left side of the equatorial plane. The other lug groove row 20 (hereinafter, second lug groove row 20b) is formed in a region on the right side. The lug grooves 18 of the first lug groove row 20a and the lug grooves 18 of the second lug groove row 20b are arranged alternately in the circumferential direction.

[0031] Each sidewall 6 is continuous with an edge of the tread 4. The sidewall 6 is located radially inward of the tread 4. The sidewall 6 is located axially outward of the carcass 10. The sidewall 6 is made of crosslinked rubber. The sidewall 6 is softer than the tread 4. The sidewall 6 is a main element of the sidewall portion. The sidewall 6 constitutes a side surface 2S of the tire 2. The side surface 2S of the tire 2 forms part of the outer surface 2G of the tire 2. Although not described in detail, the sidewall 6 is made of a crosslinked rubber that is generally used as a crosslinked rubber for the sidewall of a bias tire. 2, the position indicated by the symbol RG is the radially outer end of the sidewall 6. A pair of sidewalls 6 are disposed on either side of the equatorial plane. In FIG. 1, the sidewall 6 located on the left side of the equatorial plane, i.e., on one side, is also called the first sidewall 6a. The sidewall 6 located on the right side, i.e., on the other side, is also called the second sidewall 6b. The sidewall 6 located on the right side of the equatorial plane may be called the first sidewall 6a, and the sidewall 6 located on the left side may be called the second sidewall 6b.

[0032] The sidewall 6 is joined to the tread 4. A boundary BL between the tread 4 and the sidewall 6 connects a radially inner end RN of the tread 4 and a radially outer end RG of the sidewall 6. The radially inner end RN of the tread 4 is the radially inner end of the boundary BL between the tread 4 and the sidewall 6. The radially outer end RG of the sidewall 6 is the radially outer end of this boundary BL. A radially outer end RG of the sidewall 6 is covered by the tread 4. A radially inner end RN of the tread 4 is included in the outer surface 2G of the tire 2.

[0033] Each bead 8 is located radially inward of the sidewall 6. The bead 8 is a main element of the bead portion. The bead 8 includes a core 22 and an apex 24. The core 22 extends in the circumferential direction. Although not shown, the core 22 includes a steel wire. The apex 24 is located radially outside the core 22. The apex 24 includes a radially outer end PA of the bead 8. In this tire 2, the radially outer end PA of the bead 8 is located radially outside the radially outer end PG of the rim R. The apex 24 tapers toward the radially outer end PA. The apex 24 is made of crosslinked rubber having high rigidity. A pair of beads 8 are disposed on either side of the equatorial plane. In Fig. 1, the bead 8 located on the left side of the equatorial plane is also called the first bead 8a. The bead 8 located on the right side is also called the second bead 8b. The bead 8 located on the right side of the equatorial plane may be called the first bead 8a, and the bead 8 located on the left side may be called the second bead 8b.

[0034] The carcass 10 is located on the inside of the tread 4 and the pair of sidewalls 6. The carcass 10 bridges between the pair of beads 8. The carcass 10 forms the framework of the tire 2. 1, the position indicated by the symbol PW is the axially outer end of the carcass 10. The axially outer end PW is also called the maximum width position of the carcass 10 (hereinafter, the carcass maximum width position).

[0035] The carcass maximum width position PW is determined in the tire 2 in a normal state. If the carcass maximum width position PW cannot be determined when the tire 2 is mounted on the rim R, the carcass maximum width position PW is determined on a cut surface of the tire 2 obtained by cutting the tire 2 along a plane including the rotation axis. In this determination, the tire 2 is set so that the distance between the left and right beads 8 matches the distance between the beads 8 in the tire 2 mounted on the rim R.

[0036] The carcass 10 of the tire 2 is composed of at least three carcass plies 26. The carcass 10 shown in FIG.

[0037] Fig. 3 shows the configuration of the carcass 10. The direction indicated by the double arrow AD is the axial direction of the tire 2. The direction indicated by the double arrow CD is the circumferential direction of the tire 2. The direction perpendicular to the paper surface of Fig. 3 is the radial direction of the tire 2. The configuration of the carcass 10 shown in Fig. 3 is the configuration of the carcass 10 on the radially inner side of the tread 4.

[0038] 3, each carcass ply 26 includes a number of parallel carcass cords 28. For ease of explanation, the carcass cords 28 are represented by solid lines, but in the carcass ply 26, the carcass cords 28 are covered with a topping rubber 30. In each carcass ply 26, the carcass cords 28 do not intersect perpendicularly to the equatorial plane, but intersect obliquely with respect to the equatorial plane. The carcass cords 28 are inclined with respect to the equatorial plane. The carcass 10 has a bias structure. The carcass 10 is a carcass with a bias structure.

[0039] 3, between two radially adjacent carcass plies 26, the inclination direction of the carcass cord 28 included in one carcass ply 26 is opposite to the inclination direction of the carcass cord 28 included in the other carcass ply 26. The carcass cord 28 included in one carcass ply 26 intersects with the carcass cord 28 included in the other carcass ply 26.

[0040] The tag member 12 is located radially outward of the maximum width position PW of the carcass 10. The tag member 12 is located axially inward of the sidewall 6. The tag member 12 is entirely covered by the sidewall 6.

[0041] In this tire 2, one tag member 12 is provided only on the second sidewall 6b side. The tag member 12 may be provided only on the first sidewall 6a side. The tag member 12 may be provided on both the first sidewall 6a side and the second sidewall 6b side. From the viewpoint of reducing the risk of damage, it is preferable that the tag member 12 is provided only on the side of either the first sidewall 6a or the second sidewall 6b, that is, on the side of only one of the pair of sidewalls 6. Although multiple tag members 12 may be provided at intervals in the circumferential direction, from the viewpoint of reducing the risk of damage, it is sufficient that one tag member 12 is provided on the side of one of the sidewalls 6.

[0042] Fig. 4 is a plan view of the tag member 12. Fig. 5 is a cross-sectional view taken along line VV in Fig. 4. The tag member 12 is plate-shaped. The tag member 12 is long in the length direction and short in the width direction. As shown in FIG. 1, in the tire 2, the tag member 12 is arranged such that one end in the width direction (hereinafter, the first end 12s) is disposed on the radial outside of the tire 2, and the other end (hereinafter, the second end 12u) is disposed on the inside. In this tire 2, the first end 12s is also called the outer end, and the second end 12u is also called the inner end. The second end 12u may be disposed on the radial outside, and the first end 12s may be disposed on the radial inside. In this case, in the tire 2, the second end 12u is also called the outer end, and the first end 12s is also called the inner end.

[0043] The tag member 12 includes an RFID tag 32. In FIG. 4, the RFID tag 32 is shown by a solid line for ease of explanation, and is entirely covered with a protective body 34. The tag member 12 includes an RFID tag 32 and a protective body 34. The RFID tag 32 is located at the center of the tag member 12. The protective body 34 is made of crosslinked rubber. The protective body 34 has a rigidity similar to that of the sidewall 6. In this tire 2, the formation of a good communication environment is taken into consideration, and a crosslinked rubber having high electrical resistance is used for the protective body 34. The protective body 34 is made of rubber with high insulating properties.

[0044] Although not described in detail, the RFID tag 32 is a small and lightweight electronic component consisting of a semiconductor chip 36 that integrates a transmitting / receiving circuit, a control circuit, a memory, etc., and an antenna 38. When the RFID tag 32 receives an interrogation radio wave, it uses the received signal as electrical energy and transmits the various data stored in the memory as a response radio wave. This RFID tag 32 is a type of passive radio frequency identification transponder.

[0045] The tag member 12 is a plate-shaped member in which the RFID tag 32 is covered with crosslinked rubber. From the viewpoints of reducing the risk of damage to the RFID tag 32 and forming a good communication environment, the thickness of the tag member 12 in the meridian cross section of the tire 2 is preferably 1.0 mm or more and 2.5 mm or less. The thickness of the tag member 12 in the tire 2 is represented by the maximum thickness of the tag member 12 in the semiconductor chip 36 of the RFID tag 32. The length TL of the tag member 12 before being embedded in the tire 2 is 60 mm or more and 80 mm or less, and the width TW is 10 mm or more and 20 mm or less.

[0046] 2, the position indicated by the symbol TU is the radially inner end of the RFID tag 32 (specifically, the semiconductor chip 36). The position indicated by the symbol TS is the radially outer end of the semiconductor chip 36, i.e., the radially outer end of the RFID tag 32. In the present invention, the case where the RFID tag 32 is located radially outward from the reference position is when the inner end TU of the RFID tag 32 in the tire 2 is located radially outward from a reference position (hereinafter, the reference position), that is, when the entire RFID tag 32 is located radially outward from the reference position. The case where the RFID tag 32 is located radially inward from the reference position is when the outer end TS of the RFID tag 32 in the tire 2 is located radially inward from the reference position, that is, when the entire RFID tag 32 is located radially inward from the reference position.

[0047] As described above, the carcass 10 is composed of at least three carcass plies. The carcass 10 of the tire 2 includes two different types of carcass plies 26. The first type of carcass ply 26 is a type of carcass ply 26 that is turned up at each bead 8. The carcass ply 26 that is turned up at each bead 8 is also called a turn-up ply. The second type of carcass ply 26 is a type of carcass ply 26 that is not turned up at each bead 8. The carcass ply 26 that is not turned up at each bead 8 is also called a hanger ply.

[0048] In the present invention, the turnup ply means the carcass ply 26 that is folded back at each bead 8 so that the ends of the carcass ply 26 are located radially outside the core 22 of the bead 8. If the ends of the carcass ply 26 are not located radially outside the core 22 as a result of folding back the carcass ply 26 at the bead 8, then the carcass ply 26 is not a turnup ply but a hanger ply.

[0049] As described above, the carcass 10 of the tire 2 is composed of six carcass plies 26. Of the six carcass plies 26, four carcass plies 26 located on the inner side are turned up at each bead 8. The four carcass plies 26 located on the inner side are turn-up plies 40.

[0050] Each of the four wound-up plies 40 is folded back at each bead 8. Each wound-up ply 40 includes a ply body 40m and a pair of turned-up portions 40t. The ply body 40m spans between the pair of beads 8. Each of the pair of turned-up portions 40t is connected to the ply body 40m and turned back at the bead 8. The turned-up portions 40t of this tire 2 are turned back at the bead 8 from the inside toward the outside in the axial direction.

[0051] The turn-up portions 40t of the respective turn-up plies 40 are aligned in the axial direction on the axial outside of the bead 8. A plurality of turn-up portions 40t are aligned in the axial direction on the axial outside of the bead 8. The carcass 10 of the tire 2 includes four turn-up plies 40, so the four turn-up portions 40t are aligned in the axial direction. In the tire 2, the turn-up portion 40t located on the outermost side in the axial direction is the first turn-up portion 40t1. The turn-up portion 40t located on the axial inside of the first turn-up portion 40t1 is the second turn-up portion 40t2. The turn-up portion 40t located on the axial inside of the second turn-up portion 40t2 is the third turn-up portion 40t3. The turn-up portion 40t located on the axial inside of the third turn-up portion 40t3 is the fourth turn-up portion 40t4. In the tire 2, the fourth turn-up portion 40t4 is the turn-up portion 40t located on the axial inside of the four turn-up portions 40t.

[0052] The roll-up ply 40 including the first turn-up portions 40t1 is also called a first roll-up ply 40a, and the ply body 40m of the first roll-up ply 40a is also called a first ply body 40m1. The first roll-up ply 40a includes a first ply body 40m1 and a pair of first turn-up portions 40t1.

[0053] The roll-up ply 40 including the second turned-up portions 40t2 is also called a second roll-up ply 40b, and the ply body 40m of the second roll-up ply 40b is also called a second ply body 40m2. The second roll-up ply 40b includes a second ply body 40m2 and a pair of second turned-up portions 40t2.

[0054] The roll-up ply 40 including the third turned-up portion 40t3 is also called a third roll-up ply 40c, and the ply body 40m of the third roll-up ply 40c is also called a third ply body 40m3. The third roll-up ply 40c includes a third ply body 40m3 and a pair of third turned-up portions 40t3.

[0055] The roll-up ply 40 including the fourth turned-up portion 40t4 is also called a fourth roll-up ply 40d, and the ply body 40m of the fourth roll-up ply 40d is also called a fourth ply body 40m4. The fourth roll-up ply 40d includes a fourth ply body 40m4 and a pair of fourth turned-up portions 40t4.

[0056] In this tire 2, of the four ply bodies 40m included in the carcass 10, a first ply body 40m1 is positioned on the inner surface 2N side of the tire 2, and a fourth ply body 40m4 is positioned on the outer surface 2G side of the tire 2.

[0057] In the tire 2, the portion of the carcass 10 that is configured with the turnup ply 40 is also called the carcass body 44. As described above, among the six carcass plies 26, the four carcass plies 26 located on the inner side are the turnup plies 40. The carcass body 44 of the tire 2 includes four turnup plies 40. The carcass body 44 may be configured with at least two turnup plies 40, and may be configured with three turnup plies 40, or may be configured with five or more turnup plies 40. That is, the carcass 10 of the tire 2 includes the carcass body 44. The carcass body 44 includes at least two carcass plies 26. And, the at least two carcass plies 26 included in the carcass body 44 are the turnup plies 40 that are folded up at each bead 8.

[0058] In the tire 2, of the six carcass plies 26 constituting the carcass 10, the two carcass plies 26 located on the outer side are not turned up at each bead 8. The two carcass plies 26 located on the outer side are hanger plies 42.

[0059] Each of the two hanger plies 42 is not folded back at the bead 8. Each hanger ply 42 extends from the equatorial plane toward the corresponding bead 8. An end 42e of each hanger ply 42 is located radially inward of the bead 8.

[0060] The carcass 10 of the tire 2 includes two hanger plies 42. Of the two hanger plies, the hanger ply 42 laminated on the outer side of the carcass body 44 is a first hanger ply 42a. The hanger ply 42 laminated on the outer side of the first hanger ply 42a is a second hanger ply 42b.

[0061] In the tire 2, the portion of the carcass 10 constituted by the hanger ply 42 is also called the carcass jacket 46. As described above, in the carcass 10 of the tire 2, the first hanger ply 42a is laminated on the outside of the carcass body 44, and the second hanger ply 42b is laminated further outside the first hanger ply 42a. The carcass jacket 46 covers the carcass body 44 from the outside. As described above, of the six carcass plies 26, the two carcass plies 26 located on the outer side are the hanger plies 42. The carcass jacket 46 of the tire 2 includes two hanger plies 42. The carcass jacket 46 may be composed of three or more hanger plies 42 as long as it is composed of at least one hanger ply 42. That is, the carcass 10 of the tire 2 includes the carcass body 44 described above and the carcass jacket 46 that covers the carcass body 44 from the outside. The carcass jacket 46 includes at least one carcass ply 26. At least one carcass ply 26 included in the carcass jacket 46 is the hanger ply 42 that is not folded back at each bead 8.

[0062] In Fig. 3, the angle indicated by the symbol α1 is the angle that the carcass cord 28 included in the first winding ply 40a makes with respect to the equatorial plane. The angle indicated by the symbol α2 is the angle that the carcass cord 28 included in the second winding ply 40b makes with respect to the equatorial plane. The angle indicated by the symbol α3 is the angle that the carcass cord 28 included in the third winding ply 40c makes with respect to the equatorial plane. The angle indicated by the symbol α4 is the angle that the carcass cord 28 included in the fourth winding ply 40d makes with respect to the equatorial plane. 3, an angle indicated by the symbol β1 is an angle that the carcass cord 28 included in the first hanger ply 42a makes with respect to the equatorial plane, and an angle indicated by the symbol β2 is an angle that the carcass cord 28 included in the second hanger ply 42b makes with respect to the equatorial plane.

[0063] As described above, the carcass 10 of the tire 2 has a bias structure. The angle α1 that the carcass cords 28 included in the first winding ply 40a make with respect to the equatorial plane, i.e., the inclination angle α1 of the carcass cords 28 included in the first winding ply 40a, is preferably 25 degrees or more and 45 degrees or less. The inclination angle α2 of the carcass cords 28 included in the second winding ply 40b is preferably 25 degrees or more and 45 degrees or less. The inclination angle α3 of the carcass cords 28 included in the third winding ply 40c is preferably 25 degrees or more and 45 degrees or less. The inclination angle α4 of the carcass cords 28 included in the fourth winding ply 40d is preferably 25 degrees or more and 45 degrees or less. The inclination angle β1 of the carcass cord 28 included in the first hanger ply 42a is preferably 25 degrees or more and 45 degrees or less. The inclination angle β2 of the carcass cord 28 included in the second hanger ply 42b is preferably 25 degrees or more and 45 degrees or less.

[0064] 2, the end 40t3e of the third turned-up portion 40t3 is located radially outward of the end 40t4e of the fourth turned-up portion 40t4 located adjacent to the third turned-up portion 40t3. In the tire 2, the end 40t4e of the fourth turned-up portion 40t4 may be disposed radially outward of the end 40t3e of the third turned-up portion 40t3. In the carcass 10, the end 40t2e of the second turned-up portion 40t2 is located radially outward of the end 40t3e of the third turned-up portion 40t3 located adjacent to the second turned-up portion 40t2. In the tire 2, the end 40t3e of the third turned-up portion 40t3 may be disposed radially outward of the end 40t2e of the second turned-up portion 40t2. In the carcass 10, the end 40t1e of the first turned-up portion 40t1 is located radially outward of the end 40t2e of the second turned-up portion 40t2 located adjacent to the first turned-up portion 40t1. In the tire 2, the end 40t2e of the second turned-up portion 40t2 may be disposed radially outward of the end 40t1e of the first turned-up portion 40t1. In other words, in this tire 2, of the multiple folded portions 40t lined up in the axial direction on the axial outside of the bead 8, between two adjacent folded portions 40t, the end 40te of one folded portion 40t is located radially outside the end 40te of the other folded portion 40t.

[0065] In this tire 2, between two adjacent folded-back portions 40t, the radial position of the end 40te of one folded-back portion 40t is prevented from coinciding with the radial position of the end 40te of the other folded-back portion 40t. In other words, between two adjacent folded-back portions 40t, the end 40te of one folded-back portion 40t does not overlap with the end 40te of the other folded-back portion 40t in the axial direction. In this tire 2, strain concentration caused by the end 40te of one folded-back portion 40t overlapping with the end 40te of the other folded-back portion 40t is suppressed.

[0066] Between two adjacent folded portions 40t, the end 40te of one folded portion 40t and the end 40te of the other folded portion 40t do not overlap in the axial direction, which means that the radial height of one folded portion 40t, represented by the radial distance from the bead baseline to the end 40te of one folded portion 40t, is different from the radial height of the other folded portion 40t, represented by the radial distance from the bead baseline to the end 40te of the other folded portion 40t.

[0067] In the tire 2, among the multiple folded-back portions 40t arranged in the axial direction, the end 40t1e of the first folded-back portion 40t1 is located radially outermost. Between two adjacent folded-back portions 40t, as long as the end 40te of one folded-back portion 40t is located radially outer than the end 40te of the other folded-back portion 40t, the end 40t2e of the second folded-back portion 40t2 may be located radially outermost. The end 40t3e of the third folded-back portion 40t3 may be located radially outermost. The end 40t4e of the fourth folded-back portion 40t4 may be located radially outermost.

[0068] As shown in FIG. 2, the radial position of the end 40t1e of the first folded portion 40t1 does not match the radial position of the end 40te of the other folded portions 40t. The radial position of the end 40t2e of the second folded portion 40t2 does not match the radial position of the end 40te of the other folded portions 40t. The radial position of the end 40t3e of the third folded portion 40t3 does not match the radial position of the end 40te of the other folded portions 40t. The radial position of the end 40t4e of the fourth folded portion 40t4 does not match the radial position of the end 40te of the other folded portions 40t. In this tire 2, the ends 40te of the multiple folded portions 40t arranged in the axial direction on the axial outer side of the bead 8 are distributed in the radial direction. In this tire 2, the concentration of strain on the ends 40te of the folded portions 40t is effectively suppressed. In the tire 2, the folded-back portion 40t can effectively reinforce the bead portion while suppressing concentration of strain at the end 40te of the folded-back portion 40t. The tire 2 can increase rigidity while ensuring durability. From this viewpoint, it is preferable that the ends 40te of the multiple folded-back portions 40t arranged in the axial direction on the axially outer side of the bead 8 are dispersedly disposed in the radial direction. In this case, it is more preferable that, between two adjacent folded-back portions 40t, the radial distance from the end 40te of one folded-back portion 40t to the end 40te of the other folded-back portion 40t is 10 mm or more and 50 mm or less.

[0069] 2, in the tire 2, the end 40t2e of the second turned-up portion 40t2 is located radially outward of the maximum width position PW of the carcass 10, and the end 40t1e of the first turned-up portion 40t1 is located radially outward of the end 40t2e of the second turned-up portion 40t2. The end 40t3e of the third turned-up portion 40t3 is located radially inward of the maximum width position PW of the carcass 10, and the end 40t4e of the fourth turned-up portion 40t4 is located radially inward of the end 40t3e of the third turned-up portion 40t3. The end 40t4e of the fourth turned-up portion 40t4, that is, the end 40te of the turned-up portion 40t that is located radially inward among the ends 40te of the multiple turned-up portions 40t arranged in the axial direction on the axial outside of the bead 8, is located radially outward of the radial outer end PA of the bead 8.

[0070] The third turned portion 40t3 is located axially outward of the fourth turned portion 40t4. An end 40t3e of the third turned portion 40t3 located axially outward of the fourth turned portion 40t4 is located radially outward of an end 40t4e of the fourth turned portion 40t4. Furthermore, the second turned-up portion 40t2 is located axially outward of the third turned-up portion 40t3. An end 40t2e of the second turned-up portion 40t2 located axially outward of the third turned-up portion 40t3 is located radially outward of an end 40t3e of the third turned-up portion 40t3. The first turned-up portion 40t1 is located axially outward of the second turned-up portion 40t2. An end 40t1e of the first turned-up portion 40t1 located axially outward of the second turned-up portion 40t2 is located radially outward of an end 40t2e of the second turned-up portion 40t2.

[0071] In this tire 2, among the multiple turn-up parts 40t arranged in the axial direction on the axial outside of the bead 8, between two adjacent turn-up parts 40t, the end 40te of the turn-up part 40t located on the axial outside is located radially outside of the end 40te of the turn-up part 40t located on the axial inside. The end 40te of the turn-up part 40t located on the axial inside is covered by the turn-up part 40t located on the axial outside. Therefore, the turn-up part 40t located on the outer side can effectively reinforce the bead part while suppressing the concentration of strain on the end 40te of the turn-up part 40t located on the inner side. This tire 2 can increase rigidity while ensuring durability. From this viewpoint, it is preferable that among the multiple turn-up parts 40t arranged in the axial direction on the axial outside of the bead 8, between two adjacent turn-up parts 40t, the end 40te of the turn-up part 40t located on the axial outside is located radially outside of the end 40te of the turn-up part 40t located on the axial inside.

[0072] The cross section of tire 2 shown in Fig. 6 is a part of the meridian cross section shown in Fig. 1. Fig. 6 shows a buttress portion of this tire 2. In Fig. 6, a two-dot chain line VS represents a hypothetical side surface obtained assuming that there is no decoration such as a pattern or lettering. The hypothetical side surface VS is a reference plane of side surface 2S. The portion of side surface 2S that protrudes from the reference plane is a bulge of side surface 2S, and the portion that is recessed from this reference plane is a depression of side surface 2S.

[0073] In this tire 2, a protrusion 48, which is a bulge of a side surface 2S of the tire 2, is provided in a portion including a boundary BL between the tread 4 and the sidewall 6, i.e., in a buttress. This tire 2 includes the protrusion 48 protruding from a reference plane of the side surface 2S. 6, the length indicated by the double-headed arrow TP is the thickness of the protrusion 48. The thickness TP of the protrusion 48 is 1 mm or more and 5 mm or less. The thickness TP is represented by the maximum thickness. Although not shown, the protruding portion 48 of the tire 2 is configured as a protruding stripe that extends continuously in the circumferential direction. The protruding portion 48 may be configured as a plurality of blocks that are arranged at intervals in the circumferential direction.

[0074] 6, the cross-sectional shape of the protrusion 48 is trapezoidal. In the meridian cross section of the tire 2, the protrusion 48 has an extension along the side surface 2S. It is sufficient that the protrusion 48 extends along the side surface 2S, and the cross-sectional shape of the protrusion 28 may be rectangular or bowl-shaped.

[0075] The protrusion 48 is pedestal shaped and includes a top surface 50 and a wall surface 52 that connects the top surface 50 to the reference surface of the side surface 2S. As described above, the protrusions 48 are continuous in the circumferential direction. The top surfaces 50 of the protrusions 48 extend in the circumferential direction. In this tire 2, an outer edge 50g of the top surface 50 is a radial outer end 48g of the protrusion 48. An inner edge 50n of the top surface 50 is a radial inner end 48n of the protrusion 48. The radial inner end 48n of the protrusion 48 is located radially outside the maximum width position PW of the carcass 10. 6, the length indicated by the double-headed arrow WP is the width of the protrusion 48. The width WP of the protrusion 48 is represented by the length of a top surface 50 in a meridian cross section of the tire 2. In this tire 2, the width WP of the protrusion 48 is 10 mm or more and 50 mm or less.

[0076] As described above, the carcass 10 of the tire 2 has a bias structure. The rigidity of the side portion is higher than that of a radial structure. However, if the tread portion deforms, the radially outer portion of the side portion also deforms. Since this tire 2 is a low-profile bias tire, the side portions are shorter than those of a normal bias tire, and the tread surface 14 is formed of a relatively flat surface. Since the movement of the tread portion is suppressed, the deflection of the tread portion is small. Therefore, the concentration of strain is unlikely to occur in the buttress of this tire 2, as in a normal bias tire. As described above, in the tire 2, the buttress is provided with the convex portion 48. The tag member 12 is layered on the outer side of the carcass jacket 46 in the portion where the convex portion 48 is provided.

[0077] In this tire 2, the RFID tag 32 is placed on the buttress. Therefore, the RFID tag 32 is placed away from metal elements such as the rim R and the core 22 of the bead 8. This tire 2 can form a good communication environment.

[0078] As described above, the buttress of a low aspect bias tire is less susceptible to strain concentration, as is the case with normal bias tires. Furthermore, the protrusions 48 increase the rigidity of the buttress. In this tire 2, even if the RFID tag 32 is disposed on the buttress near the tread portion, strain concentration on the RFID tag 32 is suppressed.

[0079] As described above, the carcass 10 of the tire 2 includes the carcass jacket 46 that covers the carcass body 44 from the outside. The carcass jacket 46 is composed of the hanger ply 42 that is not folded up at each bead 8. The carcass jacket 46 does not include a folded-up portion itself. The carcass jacket 46 covers the end 40te of the folded-up portion 40t included in the carcass body 44. The carcass jacket 46 suppresses the concentration of strain at the end 40te of the folded-up portion 40t. Moreover, in the tire 2, the tag member 12 is laminated on the outside of the carcass jacket 46 that does not include a folded-up portion. In other words, the tag member 12 is adjacent to the carcass jacket 46 on the outside of the carcass jacket 46. The carcass jacket 46 is interposed between the tag member 12 and the carcass body 44. The RFID tag 32 included in the tag member 12 is disposed away from the end 40te of the folded-up portion 40t. Since the RFID tag 32 and the end 40te of the folded-back portion 40t are prevented from interfering with each other, the concentration of distortion on the RFID tag 32 is prevented.

[0080] Furthermore, in this tire 2, as shown in Fig. 6, the RFID tag 32 is located radially outside the end 40t1e of the first folded-back portion 40t1, which is located radially outermost among the multiple folded-back portions 40t arranged in the axial direction. In other words, the RFID tag 32 does not overlap with the ends 40te of the folded-back portions 40t arranged in the axial direction on the axially outer side of the bead 8 in the thickness direction of the tire 2. Mutual interference between the RFID tag 32 and the ends 40te of the folded-back portions 40t is effectively suppressed. In this tire 2, distortion is unlikely to concentrate on the RFID tag 32.

[0081] In this tire 2, the concentration of distortion on the RFID tag 32 is suppressed. In this tire 2, the decrease in durability due to the incorporation of the RFID tag 32 can be suppressed. As described above, the tire 2 can form a good communication environment. Therefore, the tire 2 can suppress a decrease in durability caused by the incorporation of an RFID tag while creating a good communication environment.

[0082] As long as the end 40te of the folded-back portion 40t does not overlap with the RFID tag 32 in the thickness direction of the tire, the end 40te of the folded-back portion 40t may be disposed immediately below the protruding portion 48. However, when the folded-back portion 40t is disposed directly below the protruding portion 48, the rigidity of the buttress increases. The rigidity of the buttress affects the deflection of the tire 2. If the rigidity of the buttress increases excessively, there is a concern that performance such as ride comfort may be impaired.

[0083] In this tire 2, as shown in FIG. 2, among the ends 40te of the multiple turned-up portions 40t arranged in the axial direction on the axial outside of the bead 8, the end 40te of the turned-up portion 40t located at the radially outermost position, that is, the end 40t1e of the first turned-up portion 40t1, is located at the radially inner side of the protruding portion 48. In this tire 2, the turned-up portion 40t is not disposed directly below the protruding portion 48. The rigidity of the buttress is prevented from being excessively increased. This tire 2 can maintain a good ride comfort. Moreover, in this tire 2, the RFID tag 32 can be disposed away from the ends 40te of all the turned-up portions 40t. This tire 2 can prevent the RFID tag 32 and the ends 40te of the turned-up portions 40t from interfering with each other. Since the concentration of distortion in the RFID tag 32 is suppressed, this tire 2 can suppress the decrease in durability caused by the incorporation of the RFID tag 32. From this viewpoint, it is preferable that the end 40te of the folded portion 40t, which is located radially outward among the ends 40te of the folded portion 40t arranged in the axial direction on the axial outside of the bead 8, is located radially inside the protrusion 48.

[0084] The length indicated by the double-headed arrow DP in Figure 6 is the radial distance from the end 40te of the turn-up portion 40t, which is located radially outermost among the ends 40te of the multiple turn-up portions 40t lined up in the axial direction on the axial outside of the bead 8, to the radially inner end 48n of the convex portion 48. In this tire 2, from the viewpoint of suppressing the contribution of the folded-back portion 40t to the rigidity of the buttress and preventing interference between the RFID tag 32 and the end 40te of the folded-back portion 40t, the radial distance DP is preferably 10 mm or more. From the viewpoint of allowing the folded-back portion 40t to contribute to ensuring the rigidity of the side portion, the radial distance DP is preferably 50 mm or less.

[0085] In this tire 2, the radially inner end RN of the tread 4 is included in the top surface 50 of the convex portion 48. As described above, the radially inner end RN of the tread 4 is the radially inner end of the boundary BL between the tread 4 and the sidewall 6. The convex portion 48 includes the boundary BL between the tread 4 and the sidewall 6. As described above, the sidewall 6 is softer than the tread 4. Distortion is likely to occur in the boundary BL between the tread 4 and the sidewall 6. However, in this tire 2, as shown in FIG. 6, for example, the RFID tag 32 is disposed away from the boundary BL. In this tire 2, the occurrence of distortion in the RFID tag 32 is effectively suppressed. In particular, the RFID tag 32 of this tire 2 is disposed radially inward of the boundary BL and away from the boundary BL. Compared to a case in which the RFID tag 32 is disposed radially outward of the boundary BL, the occurrence of distortion in the RFID tag 32 is more effectively suppressed. In this tire 2, the decrease in durability due to the incorporation of the RFID tag 32 can be suppressed. From this viewpoint, when the protrusion 48 includes the boundary BL between the tread 4 and the sidewall 6, it is preferable that the RFID tag 32 is disposed radially inward of the boundary BL and away from the boundary BL.

[0086] As described above, in the tire 2, the buttress is provided with a protruding portion 48. The protruding portion 48 of the tire 2 is composed of a circumferentially continuous protruding stripe or a plurality of blocks lined up in the circumferential direction. For example, as shown in FIG. 6 , the RFID tag 32 overlaps with the protruding portion 48 in the thickness direction of the tire 2. Specifically, when the protruding portion 48 is composed of a circumferentially continuous protruding stripe, the RFID tag 32 overlaps with the protruding stripe in the thickness direction of the tire 2. When the protruding portion 48 is composed of a plurality of blocks lined up in the circumferential direction, the RFID tag 32 overlaps with the blocks in the thickness direction of the tire 2. Since the RFID tag 32 is reliably positioned in the portion reinforced by the ridges or blocks, distortion of the RFID tag 32 is more effectively suppressed. Since the ridges or blocks protect the RFID tag 32, the RFID tag 32 is less likely to be damaged even when subjected to an external impact. The tire 2 can suppress a decrease in durability due to the incorporation of the RFID tag 32. From this viewpoint, when the ridges 48 are formed of ridges that continue in the circumferential direction, it is preferable that the RFID tag 32 overlaps with the ridges in the thickness direction of the tire 2, and when the ridges 48 are formed of a plurality of blocks aligned in the circumferential direction, the RFID tag 32 overlaps with the blocks adjacent to the RFID tag 32 in the thickness direction of the tire 2.

[0087] As described above, the carcass ply 26 includes the carcass cords 28. The carcass 10 of the tire 2 includes, as the carcass ply 26, the wraparound ply 40 and the hanger ply 42. The wraparound ply 40 and the hanger ply 42 each include the carcass cords 28. In the tire 2, the tag member 12 is laminated on a carcass jacket 46 formed of at least one hanger ply 42. The carcass cord 28 included in the hanger ply 42 is located near the RFID tag 32.

[0088] In the tire 2, the carcass cord 28 included in the hanger ply 42 is not a steel cord but is a cord made of organic fiber. In the tire 2, the occurrence of disturbance in radio waves is suppressed, and a good communication environment is formed. As described above, the tire 2 can suppress the decrease in durability caused by the incorporation of an RFID tag. Therefore, the tire 2 can suppress the decrease in durability caused by the incorporation of an RFID tag, and can communicate well with the incorporation of the RFID tag. From this viewpoint, the carcass cord 28 included in the hanger ply 42 is preferably a cord made of organic fiber. From the same viewpoint, the carcass cord 28 included in the winding ply 40 is more preferably a cord made of organic fiber. Examples of organic fibers include nylon fiber, rayon fiber, polyester fiber, and aramid fiber. Among cords made of organic fiber, a cord made of nylon fiber is preferably used as the carcass cord 28.

[0089] The carcass jacket 46 forms the outer side of the carcass 10. When the tire 2 is bent, the tension of the carcass cords 28 included in the hanger ply 42 increases. As described above, in the tire 2, the end 42e of the hanger ply 42 constituting the carcass jacket 46 is located on the radially inner side of the bead 8. Therefore, for example, as shown in FIG. 2, when the tire 2 is assembled to the rim R, the end 42e of the hanger ply 42 is sandwiched between the core 22 of the bead 8 and the rim R. The core 22 tightens the rim R. This restrains the end 42e of the hanger ply 42. Therefore, when the tire 2 is bent, the tension of the carcass cord 28 included in the hanger ply 42 is effectively increased. Since the rigidity of the side portion is increased, distortion is less likely to concentrate on the RFID tag 32 arranged on the buttress. In the tire 2, the decrease in durability due to the incorporation of the RFID tag 32 can be suppressed. From this viewpoint, it is preferable that the end 42e of the hanger ply 42 is located on the radially inner side of the bead 8.

[0090] As is clear from the above description, the present invention provides a bias tire, more specifically, a low-profile bias tire having a nominal aspect ratio of 85% or less, which can suppress the deterioration of durability caused by the incorporation of an RFID tag while establishing a good communication environment. The present invention is particularly effective in industrial vehicle tires. [Industrial Applicability]

[0091] The technology described above, which can create a good communication environment while suppressing the decrease in durability caused by the incorporation of an RFID tag, can be applied to various bias tires. [Explanation of symbols]

[0092] 2.52···Tires 4. Tread 6, 6a, 6b...Sidewall 8, 8a, 8b... Bead 10. Carcass 12 Tag material 22 cores 24 Apex 26 Carcass ply 28 Carcass Cord 32 RFID tags 34 Protective Body 36 Semiconductor Chips 38 Antenna 40, 40a, 40b, 40c, 40d... Winding ply 40m, 40m1, 40m2, 40m3, 40m4...Ply body 40t, 40t1, 40t2, 40t3, 40t4... Folded part 42, 42a, 42b Hanger ply 44 Carcass body 46 Carcass Jacket 48 Convex

Claims

1. A bias tire having a nominal aspect ratio of 85% or less, A pair of beads; a carcass extending between the pair of beads; A tread is located radially outward of the carcass and comes into contact with a road surface; A pair of sidewalls connected to the ends of the tread and positioned axially outboard of the carcass; A tag member including an RFID tag; Equipped with A protrusion is provided in a portion including a boundary between the tread and the sidewall, In a meridian cross section of the bias tire, the convex portion has an extension along a side surface of the bias tire, The carcass is composed of at least three carcass plies including a large number of carcass cords arranged in parallel, and in each of the carcass plies, each carcass cord is inclined with respect to an equator plane, The carcass includes a carcass body and a carcass jacket that covers the carcass body from the outside, The carcass body includes at least two of the carcass plies, and the at least two of the carcass plies are turnup plies that are turned up at each of the beads; Each of the winding plies includes a ply body and a pair of turn-up portions, The ply body spans between the pair of beads, and the pair of turn-up portions are each connected to the ply body and turned up at the beads, A plurality of the turned-up portions are arranged in the axial direction on the axial outer side of each of the beads, Among the plurality of folded-back portions, between two adjacent folded-back portions, an end of one folded-back portion is located radially outward of an end of the other folded-back portion, The carcass jacket includes at least one carcass ply, and the at least one carcass ply is a hanger ply that is not turned up at each of the beads; The tag member is laminated on an outer side of the carcass jacket in a portion where the protrusion is provided, The RFID tag does not overlap with the ends of the folded-up portions in the thickness direction of the bias tire. Bias tire.

2. The carcass cord included in the hanger ply is a cord made of organic fiber.

2. The bias tire according to claim 1.

3. The convex portion includes a boundary between the tread and the sidewall, the RFID tag is positioned radially inward of and spaced from the boundary; 2. The bias tire according to claim 1.

4. The convex portion is composed of a circumferentially continuous convex stripe or a plurality of circumferentially arranged blocks, When the convex portion is configured as a circumferentially continuous convex stripe, the RFID tag overlaps with the convex stripe in a thickness direction of the bias tire, When the protrusion is composed of a plurality of blocks arranged in a circumferential direction, the RFID tag overlaps with a block adjacent to the RFID tag in a thickness direction of the bias tire.

2. The bias tire according to claim 1.

5. Industrial vehicle tires, A bias tire according to any one of claims 1 to 4.

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