Pneumatic tire and manufacturing method for the same

Abstract

To suppress a carcass ply disposed around an electronic component arranged outside in a tire axial direction of a bead filler from being damaged and positional accuracy of the electronic component from deteriorating.SOLUTION: A carcass ply 50 includes an up-ply 51 which has an up-ply main body part 51 extending from a tread 30 through a pair of side walls 20 to inside in a tire axial direction of a pair of beads 10 and a wound-up part 53 wound around a bead core 11 from the up-ply main body part 51 to fold-back and extend to outside in a tire radial direction, and a down-ply 55 extending from the tread 30 through the pair of side walls 20 to outside in the tire axial direction of the pair of bead parts 10. An RFID tag 100 as an electronic component is arranged at a position, between the wound-up part 53 of the up-ply 51 and the down-ply 55, which is closer to outside in the tire radial direction than a tip 21b inside in the tire radial direction of a side wall rubber 21.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a pneumatic tire having an electronic component such as an RFID tag embedded therein, and a method for manufacturing the same. [Background technology]

[0002] Conventionally, there is known a pneumatic tire in which an RFID tag equipped with an RFID chip and an antenna is embedded, and information stored in the RFID chip is read by an external device reader via wireless communication, thereby enabling various management of the tire. Types of management include manufacturing management, supply chain management, and usage history management, and for example, the tire's usage period, mileage, wear condition, damage history, air pressure, inspection time, etc. can be confirmed while the tire is attached to the vehicle. This type of RFID tag is, for example, sandwiched between the cord reinforcing layer and the ply end reinforcing rubber part on the axially outer side of the bead filler (Patent Document 1: Figure 4). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-49920 A Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, in manufacturing a pneumatic tire, there is a process of winding and rolling up (sometimes called "turning up") the axially outer parts of the components such as the cord reinforcing layer and the carcass ply that constitutes the framework of the tire around the bead. When an RFID tag is to be placed on the bead filler side of the rolled-up part of this type of component as in Patent Document 1, the RFID tag is placed in advance and then the rolled-up part is rolled up to cover the RFID tag. Here, when the rolled-up part is placed on the RFID tag, there is a concern that the rolled-up part that comes into contact with the RFID tag may be subjected to stress from the RFID tag, resulting in deformation or damage. In addition, the contact of the rolled-up part may cause the RFID tag to be misaligned, leading to a decrease in positional accuracy.

[0005] The present invention has been made in consideration of the above-mentioned problems, and its object is to provide a pneumatic tire and a manufacturing method thereof that can prevent both damage to the carcass ply around electronic components such as RFID tags that are arranged axially outside the bead filler and a decrease in the positional accuracy of the electronic components. [Means for solving the problem]

[0006] (1) A pneumatic tire of the present invention is a pneumatic tire including a pair of beads including a bead core and a bead filler extending radially outward from the bead core, a pair of sidewalls extending radially outward from each of the beads, a tread disposed between the pair of sidewalls, and a carcass ply spanning between the pair of beads and embedded inside the tire, wherein the sidewalls include sidewall rubber, and the carcass ply includes an up ply having an up ply main body portion extending from the tread through the pair of sidewalls to the axially inward side of the pair of beads, and a turned-up portion wound around the bead core from the up ply main body portion to extend radially outward from the tire, and a down ply extending from the tread through the pair of sidewalls to the axially outward side of the pair of beads, and an electronic component is disposed between the turned-up portion of the up ply and the down ply, and at a position radially outward of a radially inner tip of the sidewall rubber.

[0007] (2) A manufacturing method for a pneumatic tire of the present invention is a method for manufacturing the pneumatic tire of the present invention, comprising the steps of arranging a pair of the beads on the up ply, winding a portion of the up ply around the beads to form the rolled-up portion, arranging the electronic component on the tire radial outside of the rolled-up portion, and covering the electronic component with the down ply by placing the down ply over the rolled-up portion. Effect of the Invention

[0008] According to the present invention, it is possible to provide a pneumatic tire and a manufacturing method thereof that can suppress both damage to the carcass ply around electronic components such as RFID tags that are arranged axially outside the bead filler and a decrease in the positional accuracy of the electronic components. [Brief description of the drawings]

[0009] [Figure 1]1 is a cross-sectional view of a pneumatic tire according to an embodiment of the present invention taken along an axial direction of the tire. [Diagram 2] FIG. 2 is an enlarged view of part II in FIG. [Diagram 3] FIG. 2 is a partial perspective view showing a schematic structure of an up-ply of a carcass ply according to an embodiment of the present invention. [Figure 4A] FIG. 2 is a plan view of an RFID tag embedded in a tire according to the embodiment. [Figure 4B] FIG. 4B is a cross-sectional view of FIG. 4A. [Figure 4C] FIG. 4B is a cross-sectional view taken along line cc of FIG. 4A. [Diagram 5] 1 is a graph showing shear strain of a carcass ply by a simulation performed in an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment will be described with reference to the drawings. Fig. 1 is a diagram showing the internal structure of a tire 1, which is a pneumatic tire according to an embodiment, and shows a cross section in the tire axial direction. Fig. 2 is an enlarged view of a portion indicated by II in Fig. 1. The tire 1 according to the embodiment is, for example, a pneumatic tire for light trucks.

[0011] First, the internal structure of a tire 1 will be described with reference to FIGS.

[0012] The cross-sectional view of FIG. 1 is a cross-sectional view in the tire axial direction (cross-sectional view of the tire meridian) in an unloaded state in which a tire 1 is mounted on a regular rim (not shown) and inflated to a regular internal pressure. The regular rim is a rim that is determined for each tire by a standard system including the standard on which the tire is based, for example, a standard rim for JATMA, and a "Measuring Rim" for TRA and ETRTO. The regular internal pressure is an air pressure that is determined for each tire by each standard in a standard system including the standard on which the tire is based, and in the case of tires for trucks and buses and tires for light trucks, it is the maximum air pressure for JATMA, the maximum value listed in the table "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES" for TRA, and "INFLATION PRESSURE" for ETRTO. For tires for passenger cars, it is usually 180 kPa, but for tires marked "Extra Load" or "Reinforced", it is 220 kPa.

[0013] In Fig. 1, the symbol S1 denotes the tire equatorial plane. The tire equatorial plane S1 is a plane perpendicular to the tire rotation axis and located at the center in the tire axial direction. The basic internal structure of the tire 1 is symmetrical with respect to the tire equatorial plane S1 in the tire axial cross section.

[0014] Here, the tire axial direction is a direction parallel to the tire rotation axis, and is the left-right direction on the paper in Figs. 1 and 2. In Figs. 1 and 2, this is illustrated as tire axial direction X. The tire axial inner side is a direction approaching the tire equatorial plane S1, and is the center side on the paper in Figs. 1 and 2. The tire axial outer side is a direction away from the tire equatorial plane S1, and is the left and right sides on the paper in Figs. 1 and 2. The tire radial direction is a direction perpendicular to the tire rotation axis, and is the up-down direction on the paper in Figs. 1 and 2. In Figs. 1 and 2, this is illustrated as tire radial direction Y. The tire radial outer side is a direction away from the tire rotation axis, and is the upper side on the paper in Figs. 1 and 2. The tire radial inner side is a direction approaching the tire rotation axis, and is the lower side on the paper in Figs. 1 and 2.

[0015] As shown in FIG. 1, the tire 1 of the embodiment includes a pair of beads 10 provided on both sides in the axial direction of the tire, a pair of sidewalls 20 extending radially outward from each of the pair of beads 10, a tread 30 arranged between the pair of sidewalls 20, a pair of shoulders 40 which are portions where each of the pair of sidewalls 20 transitions to the tread 30, a carcass ply 50 arranged spanning between the pair of beads 10, and an inner liner 60 arranged on the tire cavity side of the carcass ply 50.

[0016] The bead 10 has a bead core 11 and a bead filler 12 extending outward from the bead core 11 in the tire radial direction.

[0017] The bead core 11 is an annular member in which a rubber-coated metal bead wire is wound multiple times in the tire circumferential direction. The bead core 11 is a member that serves to fix the tire 1 filled with air to the rim. The bead filler 12 has a tapered shape that decreases in thickness as it extends from the tire radial inner side to the tire radial outer side. The bead filler 12 is provided to increase the rigidity of the peripheral portion of the bead 10 and ensure high maneuverability and stability. The bead filler 12 is made of, for example, rubber that is harder than the surrounding rubber members.

[0018] The inner end of the bead 10 in the tire radial direction is surrounded by a chafer 13 with the carcass ply 50 sandwiched therebetween. Furthermore, a rim strip rubber 14 is arranged from the inner side in the tire radial direction of the chafer 13 to the outer side in the tire axial direction. The rim strip rubber 14 includes an area arranged axially outward of the bead core 11 and a part of the bead filler 12. The rim strip rubber 14 contacts the inner surface of the rim on which the tire 1 is mounted.

[0019] The sidewall 20 includes a sidewall rubber 21 disposed axially outward of the carcass ply 50. The sidewall rubber 21 constitutes the outer wall surface of the tire 1. As shown in Fig. 2, an end 21a of the sidewall rubber 21 on the inner side in the tire radial direction covers a part of the rim strip rubber 14. The sidewall rubber 21 is the part that bends the most when the tire 1 performs its cushioning function, and flexible rubber having fatigue resistance is usually used for the sidewall rubber 21.

[0020] The tread 30 has a tread rubber 35, and a belt 31 and a cap ply 34 embedded inside the tread rubber 35. The belt 31 is disposed on the outer side of the carcass ply 50 in the tire radial direction. The cap ply 34 is disposed on the outer side of the belt 31 in the tire radial direction.

[0021] The belt 31 is a member that reinforces the tread 30. The belt 31 of the embodiment has a two-layer structure including an inner belt 32 and an outer belt 33 laminated on the tire outer surface side of the inner belt 32. Each of the belts 32, 33 has a structure in which a plurality of belt cords such as steel cords are covered with rubber. The inner belt 32 is wider than the outer belt 33. By providing the belt 31, the rigidity of the tire 1 is ensured, and the contact of the tread 30 with the road surface is improved. Note that the belt 31 is not limited to a two-layer structure, and may have a single layer structure, or a three-layer or more layer structure.

[0022] The cap ply 34 is a member that reinforces the tread 30 together with the belt 31. The cap ply 34 covers the entire belt 31 from the tire outer surface side. The cap ply 34 has a structure in which a plurality of insulating organic fiber cords such as polyamide fiber are covered with rubber. By providing the cap ply 34, it is possible to improve durability and reduce road noise during driving. The cap ply 34 is not limited to a single-layer structure as in the embodiment, but may have a two-layer structure, or a three-layer structure or more. In addition, instead of the cap ply 34 that covers the belt 31, an edge ply that covers the end of the belt 31 in the tire axial direction may be used.

[0023] The tread rubber 35 is disposed on the outer side in the tire radial direction of the cap ply 34. The tread rubber 35 forms a tread surface 36 which is the outer surface of the tread 30 and comes into contact with the road surface. An end 35a on the outer side in the tire axial direction of the tread rubber 35 protrudes outward in the tire axial direction beyond the outer end of the cap ply 34 in the tire axial direction and bends inward in the tire radial direction, covering the outer end of the sidewall rubber 21 in the tire radial direction.

[0024] The shoulder 40 includes an area of ​​an axially outer end 35a of the tread rubber 35. In the tire 1 of the embodiment, a shoulder rubber 41 is sandwiched between the tread rubber 35 in an area corresponding to the shoulder 40 and the carcass ply 50. The tire outer surface side of the shoulder rubber 41 is covered with a part of each of the inner belt 32, the cap ply 34, the tread rubber 35, and the sidewall rubber 21.

[0025] The carcass ply 50 constitutes a ply that forms the framework of the tire 1. The carcass ply 50 is embedded in the tire 1 in a manner that passes between a pair of beads 10, a pair of sidewalls 20, a pair of shoulders 40, and the tire cavity side of the tread 30. In the tread 30, a belt 31 is disposed on the outer side of the carcass ply 50 in the tire radial direction.

[0026] The carcass ply 50 of the embodiment includes an up ply 51 and a down ply 55. In the region of the tread 30, the up ply 51 is disposed on the outer side of the inner liner 60 in the tire radial direction, and the down ply 55 is disposed on the outer side of the up ply 51 in the tire radial direction.

[0027] The up ply 51 has an up ply main body 52 that extends from the tread 30 through the pair of shoulders 40 and the pair of sidewalls 20 toward the axially inner side of each of the pair of beads 10, and a pair of turned-up portions 53 that are wound around each of the pair of bead cores 11 from the up ply main body 52 and extend radially outward from the pair of bead cores 11. The turned-up portions 53 extend from the bead cores 11 to the middle of the bead fillers 12 in the radial direction of the tire.

[0028] The down ply 55 extends from the tread 30 through the pair of sidewalls 20 and the pair of shoulders 40 to the axially outer side of each of the pair of beads 10. The down ply 55 overlaps the tire outer surface side of the up ply main body 52 of the up ply 51 from the tread 30 to the tire radially outer tip 12a of the bead filler 12, from which it branches off from the up ply main body 52 and extends to the tire radially outer side of the bead filler 12. The down ply 55 has a down ply main body 56 which is a portion between the tips 12a of the pair of bead fillers 12, and a descending portion 57 which is a portion from the down ply main body 56 to the tire radially inner side.

[0029] The down ply body 56 of the down ply 55 is disposed in an area extending from the tread 30 through the pair of shoulders 40 to the pair of sidewalls 20 and to the tip 12a of each of the pair of bead fillers 12. The descending portion 57 of the down ply 55 extends from the tip 12a of each of the pair of bead fillers 12 to the tire radially inward while overlapping the tire axially outer side of the bead filler 12, and further extends to the tire radially inward while overlapping the tire axially outer side of the turned-up portion 53 of the up ply 51. The tire radially inner end 57a of the descending portion 57 covers the tire axially outer part of the chafer 13. The tire radially inner tip 57b of the descending portion 57 is located between the chafer 13 and the rim strip rubber 14, and is located at approximately the same position as the tire radially inner tip 11b of the bead core 11 in the tire radial direction.

[0030] A shock absorbing rubber 15 is disposed on the axially outer side of the bead filler 12, between the descending portion 57 of the down ply 55 and the sidewall rubber 21 and the rim strip rubber 14. The shock absorbing rubber 15 is covered by the sidewall rubber 21 and the rim strip rubber 14, and is not exposed on the outer surface of the tire and does not come into contact with the rim. The hardness of the shock absorbing rubber 15 is set to be equal to or less than that of the bead filler 12, for example.

[0031] FIG. 3 is a partial perspective view showing the configuration of the up ply 51. The down ply 55 has the same configuration. That is, the up ply 51 and the down ply 55 have a configuration in which a plurality of ply cords 50A in a parallel state are covered with a topping rubber 50B as shown in FIG. The plurality of ply cords 50A extend, for example, along a plane along the tire axial direction, and are arranged side by side in the tire circumferential direction. The ply cords 50A are made of insulating organic fiber cords such as polyester and polyamide. It is preferable that the ply cords 50A of the up ply 51 and the ply cords 50A of the down ply 55 are made of the same material, and that the topping rubber 50B of the up ply 51 and the topping rubber 50B of the down ply 55 are made of the same material.

[0032] The inner liner 60 forms the tire cavity surface by covering the inner surface of the up-ply main body 52 of the up-ply 51 between the pair of beads 10. The inner liner 60 is made of air-permeable resistant rubber and prevents air in the tire cavity from leaking to the outside.

[0033] Here, the rubber used for the bead filler 12 has a hardness higher than at least the sidewall rubber 21 and the inner liner 60. The hardness of the rubber is a hardness tested according to "JIS K6253-3:2012 durometer hardness type A".

[0034] For example, when the hardness of the sidewall rubber 21 is used as a standard, the hardness of the bead filler 12 is preferably about 1.2 to 7 times the hardness of the sidewall rubber 21. By setting the hardness at such a level, it is possible to ensure a balance between the flexibility of the tire and the rigidity in the vicinity of the bead 10.

[0035] As shown in Figs. 1 and 2, a tire 1 according to the embodiment has an RFID tag 100 embedded therein as an electronic component.

[0036] 4A to 4C show an example of an RFID tag 100 according to the embodiment, where FIG. 4A is a plan view of the RFID tag 100, FIG. 4B is a cross-sectional view taken along line bb in FIG. 4A, and FIG. 4C is a cross-sectional view taken along line cc in FIG. 4A.

[0037] 4A to 4C, the RFID tag 100 is a passive radio frequency identification transponder equipped with an RFID chip 101 and an antenna 102 for communicating with an external device. The RFID tag 100 enables various management of the tire 1 by reading information stored in the RFID chip 101 with a reader of an external device via wireless communication. The types of management include manufacturing management, supply chain management, and usage history management. For example, the usage period, mileage, wear state, damage history, air pressure, inspection time, etc. of the tire can be confirmed while the tire is attached to the vehicle.

[0038] Note that various antennas such as a coil spring antenna, a plate-shaped antenna, a rod-shaped antenna, etc. may be used as the antenna 102. For example, the antenna may be formed by printing a predetermined pattern on a flexible substrate.

[0039] As shown in FIGS. 4A to 4C, the RFID tag 100 of the embodiment is covered with a protective member 200 and embedded inside the tire 1 in this state.

[0040] The protective member 200 is composed of two rubber sheets 201, 202 that sandwich and protect the RFID tag 100. The rubber sheets 201, 202 are preferably made of the same rubber, i.e., rubber with the same compounding. In this case, the rubber sheets 201, 202 may be integrated after the tire vulcanization process. Furthermore, the thickness t of each of the rubber sheets 201, 202 is preferably 0.5 mm or more and 1.5 mm or less.

[0041] The rubber sheets 201 and 202 of the protective member 200 may be made of raw rubber in an unvulcanized state or rubber in a vulcanized state. The rubber sheets 201 and 202 in a vulcanized state do not undergo plastic deformation like raw rubber, and therefore can adequately protect the RFID tag 100. In addition, it is preferable that the rubber sheets 201 and 202 of the protective member 200 are made of the same rubber, i.e., rubber having the same compounding, as the topping rubbers 50B of the up-ply 51 and the down-ply 55. In this case, the rubber sheets 201 and 202 may be integrated after the vulcanization process of the tire, and further, the topping rubbers 50B of the up-ply 51 and the down-ply 55 that are in contact with the rubber sheets 201 and 202 may be integrated with the rubber sheets 201 and 202.

[0042] The protective member 200 is not limited to being configured by two rubber sheets 201 and 202, and various other configurations can be adopted. For example, the protective member 200 may be configured by one rubber sheet 201, and the rubber sheet 201 may be provided on only one side of the RFID tag 100. When the protective member 200 is provided on only one side of the RFID tag 100, the overall thickness can be made thinner. The rubber sheet constituting the protective member 200 may be configured to cover at least a part of the RFID tag 100 as long as it has an effect of reducing stress or the like.

[0043] As shown in FIG. 2, the RFID tag 100 is disposed between the rolled-up portion 53 of the up ply 51 and the descending portion 57 of the down ply 55. In other words, the RFID tag 100 is disposed at a portion where the rolled-up portion 53 of the up ply 51 and the descending portion 57 of the down ply 55 overlap. In the embodiment, the RFID tag 100 contacts both the rolled-up portion 53 of the up ply 51 and the descending portion 57 of the down ply 55. The rolled-up portion 53 of the up ply 51 and the descending portion 57 of the down ply 55 are in close contact with each other around the RFID tag 100. The RFID tag 100 is disposed at a position on the outer side in the tire radial direction than the tip 21b on the inner side in the tire radial direction of the sidewall rubber 21.

[0044] A distance G in the tire radial direction between a rolled-up end 53a, which is the tip end on the outer side in the tire radial direction of the rolled-up portion 53 of the up-ply 51, and the RFID tag 100 is preferably 4 mm or more.

[0045] In addition, it is preferable that the turned-up end 53a of the turned-up portion 53 of the up-ply 51 is disposed radially outward of the outer tip 14a of the rim strip rubber 14 in the tire radial direction.

[0046] Furthermore, when the distance in the tire radial direction from the tip 11a on the outer side in the tire radial direction of the bead core 11 to the tip 12a on the outer side in the tire radial direction of the bead filler 12 is L, it is preferable that the turned-up end 53a of the up ply 51 is disposed in the tire radial direction between a position L1 that is 50% of the distance L from the tip 11a on the outer side in the tire radial direction of the bead core 11 and a position L2 that is 80% of the distance L. In other words, it is preferable that the turned-up end 53a of the up ply 51 is disposed in a range L3 that is 50% to 80% of the distance L from the tip 11a on the outer side in the tire radial direction of the bead core 11 in the tire radial direction.

[0047] The method for manufacturing the tire 1 having the above configuration includes the following steps.

[0048] That is, the process includes the steps of arranging a pair of beads 10 on the up ply 51, winding a portion of the up ply 51 around each of the pair of bead cores 11 and turning it up radially outward in the tire direction to form a pair of rolled-up portions 53, arranging an RFID tag 100 covered with a protective material 200 on the radially outward side of one of the pair of rolled-up portions 53, and arranging a down ply 55 on the up ply 51 and covering the rolled-up portion 53 with the downward portion 57 of the down ply 55, thereby covering the RFID tag 100 covered with the protective material 200 with the downward portion 57.

[0049] According to the tire 1 of the embodiment having the above configuration, the following effects are achieved.

[0050] (1) A tire 1 according to an embodiment includes a pair of beads 10 including a bead core 11 and a bead filler 12 extending from the bead core 11 to the outside in the tire radial direction, a pair of sidewalls 20 extending from each of the beads 10 to the outside in the tire radial direction, a tread 30 disposed between the pair of sidewalls 20, and a carcass ply 50 that is bridged between the pair of beads 10 and embedded inside the tire. The sidewalls 20 include a sidewall rubber 21, and the carcass ply 50 extends from the tread 30 through the pair of sidewalls 20 to the tyre of the pair of beads 10. The down ply 55 includes an up ply 51 having an up ply main body 52 extending axially inward and a rolled-up portion 53 that is wound around the bead core 11 from the up ply main body 52 and extends radially outward from the tire, and a down ply 55 that extends from the tread 30 through a pair of sidewalls 20 to the axially outward of a pair of beads 10, and an RFID tag 100 is disposed between the rolled-up portion 53 of the up ply 51 and the down ply 55, and at a position radially outward of the radially inward tip 21b of the sidewall rubber 21.

[0051] According to the tire 1 according to the embodiment, when the tire is manufactured by the above-mentioned manufacturing method, the RFID tag 100 is disposed on the axially outer side of the turned-up portion 53 of the up-ply 51 after the turning-up, and then the downward portion 57 of the down-ply 55 is placed on the turned-up portion 53 to cover the RFID tag 100 with the downward portion 57. Therefore, there is no process of turning up the turned-up portion 53 while covering the RFID tag 100. As a result, there is no risk that the turned-up portion 53 will receive stress from the RFID tag 100 during manufacturing. On the other hand, the down-ply 55 is only overlapped by placing the downward portion 57 on the turned-up portion 53 of the up-ply 51, so that it is unlikely to receive stress from the RFID tag 100. For these reasons, although the up-ply 51 and the down-ply 55 come into contact with the RFID tag 100, they are unlikely to receive stress from the RFID tag 100. Therefore, deformation or damage to the up-ply 51 and the down-ply 55 due to the RFID tag 100 is suppressed. In addition, since there is no process of turning up the roll-up portion 53 of the up-ply 51 while covering the RFID tag 100, the RFID tag 100 is less likely to become misaligned, and as a result, a decrease in the positional accuracy of the RFID tag 100 is suppressed.

[0052] (2) In the tire 1 of the above embodiment (1), it is preferable that the distance G between the RFID tag 100 and the rolled-up end 53a, which is the radially outer tip of the rolled-up portion 53 of the up-ply 51, is 4 mm or more in the tire radial direction.

[0053] This prevents the plies 51, 55 from being separated by the RFID tag 100 disposed between the rolled-up portion 53 of the up-ply 51 and the descending portion 57 of the down-ply 55. If the distance G is shorter than 4 mm, the RFID tag 100 is likely to cause the plies 51, 55 to peel off and separate. In addition, since the RFID tag 100 is securely held between the rolled-up portion 53 of the up-ply 51 and the descending portion 57 of the down-ply 55, deformation and damage to the RFID tag 100 are prevented even during driving, etc.

[0054] (3) In the tire 1 of the above embodiments (1) and (2), the rim strip rubber 14 is arranged axially outward of the bead 10, and it is preferable that the rolled-up end 53a, which is the radially outer tip of the rolled-up portion 53 of the up-ply 51, is arranged radially outward of the radially outer tip 14a of the rim strip rubber 14.

[0055] This ensures a distance between the rim on which the tire 1 is mounted and the RFID tag 100, thereby preventing the influence of the rim from causing a decrease in the communication performance of the RFID tag 100. In addition, since the overlap length between the rolled-up portion 53 of the up ply 51 and the descending portion 57 of the down ply 55 is ensured, separation of these plies 51, 55 is prevented.

[0056] (4) In the tire 1 according to the above embodiments (1) to (3), if the distance in the tire radial direction from the tire radially outer tip 11a of the bead core 11 to the tire radially outer tip 12a of the bead filler 12 is L, it is preferable that the turned-up end 53a, which is the tire radially outer tip of the turned-up portion 53 of the up ply 51, is positioned within a range L3 of 50% to 80% of the distance L from the tire radially outer tip 11a of the bead core 11 in the tire radial direction.

[0057] This ensures a distance between the bead core 11 and the RFID tag 100, thereby preventing the communication performance of the RFID tag 100 from being deteriorated due to the influence of the bead core 11. Also, a distance is ensured from the tip 12a on the outer side in the tire radial direction of the bead filler 12, where the up-ply main body portion 52 of the up-ply 51 and the down-ply main body portion 56 of the down-ply 55 branch off, to the rolled-up end 53a of the rolled-up portion 53 of the up-ply 51, thereby preventing the up-ply main body portion 52 and the down-ply main body portion 56 from being separated.

[0058] (5) In the tire 1 according to the above embodiments (1) to (4), each of the up ply 51 and the down ply 55 includes a ply cord 50A and a topping rubber 50B covering the ply cord 50A, and the RFID tag 100 is covered with a rubber protective member 200. It is preferable that the topping rubber 50B and the protective member 200 are made of the same rubber.

[0059] As a result, the RFID tag 100 is appropriately protected by the protective member 200. In addition, distortion of the up ply 51 and the down ply 55 around the RFID tag 100 caused by tire deformation during running is suppressed, and each ply 51, 55 is less likely to be deformed or damaged.

[0060] (6) In the tire 1 of the above embodiment (5), it is preferable that the ply cord 50A of the up ply 51 and the ply cord 50A of the down ply 55 are made of the same material, and that the topping rubber 50B of the up ply 51 and the topping rubber 50B of the down ply 55 are made of the same material.

[0061] This makes it difficult for uneven distortion to occur in the plies 51, 55 due to sandwiching the RFID tag 100, and thus deformation and damage to the plies 51, 55 are suppressed.

[0062] (7) In the tire 1 according to the embodiment (5) above, the protective member 200 covering the RFID tag 100 includes two rubber sheets 201, 202 sandwiching the RFID tag 100, and these rubber sheets 201, 202 are formed from the same type of rubber. It is preferable that each of these rubber sheets 201, 202 has a thickness of 0.5 mm or more and 1.5 mm or less.

[0063] This makes it difficult for uneven distortion to occur in the plies 51, 55 due to the RFID tag 100 being sandwiched between the protective member 200, and thus deformation and damage to the plies 51, 55 are suppressed.

[0064] (8) In the tire 1 according to the embodiment (5) above, the protective member 200 includes a rubber sheet that contacts at least a portion of the RFID tag 100, the rubber sheets being formed from the same type of rubber, and each rubber sheet preferably has a thickness of 0.5 mm or more and 1.5 mm or less.

[0065] This allows the overall thickness of the RFID tag 100 and the protection member 200 to be made thinner.

[0066] (9) A manufacturing method of tire 1 according to an embodiment is a method of manufacturing tire 1 according to the embodiment described above in (1) to (7), and includes the steps of arranging a pair of beads 10 on up ply 51, winding a portion of up ply 51 around bead 10 to form rolled-up portion 53, arranging RFID tag 100 on the tire radial outside of rolled-up portion 53, and placing down ply 55 over rolled-up portion 53 to cover RFID tag 100 with down ply 55.

[0067] According to this manufacturing method, the RFID tag 100 is disposed on the axially outer side of the rolled-up portion 53 of the up-ply 51 that has been turned up in advance, and then the downward portion 57 of the down-ply 55 is placed on the rolled-up portion 53 to cover the RFID tag 100 with the downward portion 57. Therefore, there is no process of turning up the rolled-up portion 53 while covering it with the RFID tag 100. This eliminates the risk that the rolled-up portion 53 will receive stress from the RFID tag 100 during manufacturing. On the other hand, the down-ply 55 is not easily subjected to stress from the RFID tag 100 because the downward portion 57 of the down-ply 55 is simply placed on the rolled-up portion 53 of the up-ply 51 and overlapped therewith. For these reasons, although the up-ply 51 and the down-ply 55 come into contact with the RFID tag 100, they are not easily subjected to stress from the RFID tag 100. As a result, a tire in which the up-ply 51 and the down-ply 55 are less likely to be deformed or damaged can be manufactured. In addition, since there is no process of turning up the rolled-up portion 53 of the up-ply 51 while covering it over the RFID tag 100, the RFID tag 100 is less likely to become misaligned, and as a result, a tire can be manufactured in which the positional accuracy of the RFID tag 100 is less likely to decrease.

[0068] The present invention is not limited to the above-described embodiment, and even if modifications and improvements are made within the scope of the present invention, they will still be included in the scope of the present invention.

[0069] For example, each of the up ply 51 and the down ply 55 constituting the carcass ply 50 in the embodiment has a single-layer structure, but may have a two-layer structure or a three-layer or more structure. The number of layers may be the same for the up ply 51 and the down ply 55, or may be different. In any case, the RFID tag 100 is disposed between the turned-up portion 53 of the up ply 51 and the down ply 55.

[0070] In the above embodiment, the RFID tag 100 is the electronic component, but the electronic component according to the present invention may be another electronic component such as an IC tag.

[0071] The RFID tag 100 does not necessarily have to be covered with the protective member 200 and embedded inside the tire 1. In other words, the RFID tag 100 consisting of only the RFID chip 101 and the antenna 102 may be embedded inside the tire 1 without using the protective member 200.

[0072] The configuration of the tire 1 according to the embodiment described above can be adopted for various vehicles such as passenger cars, trucks, buses, etc., in addition to light trucks. EXAMPLES

[0073] A simulation was performed to measure the shear strain occurring at the overlapping portion of the turned-up portion 53 of the up-ply 51 and the descending portion 57 of the down-ply 55 when a load of 1285 kgf was applied as 100% load to a pneumatic tire of "205 / 85R16" with normal internal pressure having the same configuration as the above embodiment. The results are shown in the graph of Fig. 5. The tire standard adopted was JATMA for normal internal pressure and 100% load.

[0074] In FIG. 5, the change in shear strain of the downward portion 57 of the down ply 55 is shown, starting from the inner end of the overlapping portion between the turned-up portion 53 of the up ply 51 and the downward portion 57 of the down ply 55 (indicated by the symbol P in FIG. 2) extending from the starting point to the outer side in the tire radial direction, that is, through the overlapping portion from the starting point to the turned-up end 53a of the up ply 51, and further to the vicinity of the outer tip 12a of the bead filler 12 in the tire radial direction. The "length" on the horizontal axis of FIG. 5 is the actual length along the deformation of each ply 51, 55 (sometimes called the peri length), and the shear strain was measured at predetermined intervals along that length. FIG. 5 also shows the positions of the inner tip 21b of the sidewall rubber 21 in the tire radial direction, the turned-up end 53a of the up ply 51, and the RFID tag 100.

[0075] 5, the overlapping portion of the turned-up portion 53 of the up ply 51 and the down ply 55 has almost equal shear strains, except for the vicinity of the starting point P, and decreases in a similar manner toward the outer side in the tire radial direction, reaching a minimum at the turned-up end 53a. From the viewpoint of being least susceptible to shear strain, therefore, it is desirable to place the RFID tag 100 near the turned-up end 53a between the turned-up portion 53 of the up ply 51 and the down ply 55. However, since there is a concern about separation of the plies near the turned-up end 53a as described above, it is desirable to place the RFID tag 100 close to the turned-up end 53a but at a predetermined distance inward in the tire radial direction from the turned-up end 53a, and this distance (distance G in FIG. 2) is preferably 4 mm or more as described above. [Explanation of symbols]

[0076] 1... tire, 10... bead, 11... bead core, 11a... tire radial outer tip of bead core, 12... bead filler, 12a... tire radial outer tip of bead filler, 14... rim strip rubber, 20... sidewall, 21... sidewall rubber, 21b... tire radial inner tip of sidewall rubber, 30... tread, 50... carcass ply, 50A... ply cord, 50B... topping rubber, 51... up ply, 52... up ply main body, 53... rolled up part, 53a... rolled up end, 55... down ply, 100... RFID tag (electronic component), 200... protective member, 201, 202... rubber sheet.

Claims

1. A pair of beads including a bead core and a bead filler extending from the bead core outward in a radial direction of the tire; A pair of sidewalls extending radially outward from each of the beads; a tread disposed between the pair of sidewalls; A carcass ply that is bridged between the pair of beads and embedded inside the tire, The sidewall includes a sidewall rubber, The carcass ply is an up-ply having an up-ply main body portion extending from the tread through the pair of sidewalls toward an axially inner side of the pair of beads, and a turned-up portion wound around the bead core from the up-ply main body portion and extending radially outward from the tire; a down ply extending from the tread through the pair of sidewalls to an axially outer side of the pair of beads, The pneumatic tire comprises an electronic component disposed between the turned-up portion of the up ply and the down ply, and at a position radially outward of a radially inner tip of the sidewall rubber.

2. The pneumatic tire according to claim 1 , wherein a distance between a turned-up end, which is a tip end on an outer side in the tire radial direction of the turned-up portion of the up-ply, and the electronic component is 4 mm or more in the tire radial direction.

3. A rim strip rubber is disposed on the outer side of the bead in the tire axial direction, 3. The pneumatic tire according to claim 1, wherein a turned-up end, which is a radially outer tip of the turned-up portion of the up-ply, is positioned radially outward of a radially outer tip of the rim strip rubber.

4. 3. The pneumatic tire according to claim 1, wherein, when a distance in the tire radial direction from a tip of the bead core on the outer side in the tire radial direction to a tip of the bead filler on the outer side in the tire radial direction is L, a turned-up end that is a tip of the turned-up portion of the up ply on the outer side in the tire radial direction is positioned within a range of 50% to 80% of the distance L from the tip of the bead core on the outer side in the tire radial direction in the tire radial direction.

5. Each of the up ply and the down ply includes a ply cord and a topping rubber covering the ply cord, The electronic components are covered with a rubber protective member. The pneumatic tire according to claim 1 , wherein the topping rubber and the protective member are made of the same rubber.

6. The pneumatic tire according to claim 5 , wherein the ply cord of the up ply and the ply cord of the down ply are made of the same material, and the topping rubber of the up ply and the topping rubber of the down ply are made of the same material.

7. the protective member includes two rubber sheets that sandwich the electronic component, The rubber sheet is made of the same rubber, The pneumatic tire according to claim 5 , wherein each of the rubber sheets has a thickness of 0.5 mm or more and 1.5 mm or less.

8. the protective member includes a rubber sheet in contact with at least a portion of the electronic component, The rubber sheet is made of the same rubber, The pneumatic tire according to claim 5 , wherein each of the rubber sheets has a thickness of 0.5 mm or more and 1.5 mm or less.

9. A method for manufacturing the pneumatic tire according to claim 1 or 2, disposing a pair of said beads on said up-ply; wrapping a portion of the up-ply around the bead to form the turnup; disposing the electronic component on an outer side of the rolled-up portion in a tire radial direction; and covering the electronic component with the down ply by placing the down ply over the turned-up portion.

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