JP2023087601A - pneumatic tire - Google Patents

Abstract

To readily fit an RFID tag in a pneumatic tire that includes: a bead filler having an outside surface made of a resin material; and a carcass ply including a cord covered with a coating rubber.SOLUTION: A pneumatic tire 10 includes: a carcass 16 including a cord covered with a coating rubber; a bead filler part 18 having an outside surface opposite to the carcass 16 and made of a resin that is harder than the coating rubber; and an RFID tag 50 installed to the bead filler part 18.SELECTED DRAWING: Figure 1

Description

The present invention relates to pneumatic tires.

Conventionally, an RFID tag is embedded inside a tire, and information is stored in the RFID tag by wireless communication, and the stored information is read. Various modes have also been proposed for the mounting position of the RFID. For example, in Patent Literature 1, an RFID tag is provided inside the tire belt portion in the tire radial direction and on the outside in the tire width direction.

It is a technique for a rubber tire such as Patent Document 1, and for a pneumatic tire in which a resin material is a part of the tire component, it is necessary to consider the position where the RFID tag is provided.

JP 2019-018717 A

SUMMARY OF THE INVENTION An object of the present invention is to easily attach an RFID tag to a pneumatic tire having a bead filler whose outer surface is made of a resin material and a carcass ply in which a cord is coated with coating rubber.

A pneumatic tire according to a first aspect includes a carcass having cords coated with a coating rubber, a bead filler portion having an outer surface facing the carcass formed of a resin harder than the coating rubber, and the bead filler portion. and an RFID tag provided in the .

In the pneumatic tire according to the first aspect, since the RFID tag is provided in the bead filler portion formed of resin, the RFID tag can be easily attached during manufacturing compared to the case where the RFID tag is provided in the rubber portion. . Therefore, an RFID tag can be easily attached to a pneumatic tire having a bead filler whose outer surface is made of a resin material and having a carcass ply in which a cord is coated with coating rubber.

In the pneumatic tire according to the second aspect, in the cross-sectional shape, the bead filler portion includes a thick portion in which the bead core is embedded and arranged inside in the tire radial direction, and the thick portion arranged outside in the tire radial direction. The RFID tag is arranged in the thin portion of the bead filler portion.

In the pneumatic tire according to the second aspect, the RFID tag is arranged in the thin portion in the tire radial direction of the bead filler portion. Since the thin portion in the tire radial direction of the bead filler portion is arranged at a position away from the bead core, it is possible to suppress interference between the bead core and the RFID tag during communication.

In the pneumatic tire according to the third aspect, the RFID tag is arranged on the inner peripheral portion of the bead filler portion in the tire width direction.

In the pneumatic tire according to the third aspect, the RFID tag is arranged on the inner peripheral portion in the tire width direction of the bead filler portion. The inner peripheral portion of the bead filler portion in the tire width direction is relatively resistant to deformation during running, and can suppress damage to the RFID tag.

In the tire according to the fourth aspect, the RFID tag has a resin coating portion in which the body chip and the antenna are embedded.

In the tire according to the fourth aspect, the resin coating portion of the RFID tag can be easily integrated with the bead filler portion by melting or the like.

As described above, according to the pneumatic tire of the present invention, the RFID tag can be easily attached to the pneumatic tire having the bead filler whose outer surface is made of a resin material and the carcass ply in which the cord is coated with coating rubber. be able to.

1 is a half cross-sectional view along a tire rotation axis showing a pneumatic tire according to an embodiment of the present invention; FIG. 4 is a cross-sectional view of a carcass ply and a bead filler portion; FIG. FIG. 4 is a cross-sectional view of the bead filler portion before being sandwiched between carcass plies; (A) is a plan view and (B) is a side view of the RFID tag provided on the tire of the present embodiment. It is a section perspective view showing a tire concerning this embodiment. FIG. 8 is a cross-sectional view of a bead filler portion before being sandwiched between carcass plies according to a modification; It is a half section view along a tire axis of rotation showing a pneumatic tire of other modifications. It is sectional drawing (A) and (B) of the bead filler part before inserting into a carcass ply which concerns on another modification.

A pneumatic tire 10 according to an embodiment of the present invention will be described with reference to FIGS. 1 to 5. FIG. In the drawings, the arrow R direction indicates the tire radial direction, and the arrow W direction indicates the tire width direction. A tire radial direction means a direction orthogonal to a tire rotation axis (not shown). The tire width direction means a direction parallel to the tire rotation axis. The tire width direction can also be called the tire axial direction.

The dimensional measurement method of each part is according to the method described in the 2021 edition of the YEAR BOOK issued by JATMA (Japan Automobile Tire Manufacturers Association). If TRA standards and ETRTO standards are applied at the place of use or manufacturing, follow the respective standards.

As shown in FIG. 1, a pneumatic tire 10 of the present embodiment is, for example, a so-called radial pneumatic tire used for passenger cars, and includes a pair of bead portions 20 in which bead cores 12 are embedded. A carcass 16 composed of one carcass ply 14 straddles between one bead portion 20 and the other bead portion 20 . FIG. 1 shows the shape of the pneumatic tire 10 attached to the standard rim 19 in its natural state before being filled with air (internal pressure=atmospheric pressure).

The carcass ply 14 is formed by coating a plurality of cords 13A (not shown in FIG. 1, see FIG. 2) extending in the radial direction of the pneumatic tire 10 with a coating rubber 13B (not shown in FIG. 1, see FIG. 2). formed by That is, the pneumatic tire 10 of this embodiment is a so-called radial pneumatic tire. The material of the cords 13A of the carcass ply 14 is, for example, PET, but other conventionally known materials may be used.

The carcass 16 has an end portion in the tire width direction folded over the bead core 12 outward in the tire radial direction. A portion of the carcass 16 extending from one bead core 12 to the other bead core 12 is called a body portion 16A, and a portion folded back from the bead core 12 is called a folded portion 16B.

A bead filler portion 18 is arranged between the body portion 16A of the carcass 16 and the folded portion 16B. The bead filler portion 18 gradually decreases in thickness from the bead core 12 toward the outside in the tire radial direction. In the pneumatic tire 10 of the present embodiment, the bead portion 20 is the entire portion of the bead filler portion 18 on the inner side in the tire radial direction from the tire radial outer end 18A.

(bead core)
As shown in FIG. 3, the bead core 12 of this embodiment has a bead cord 12B covered with a covering layer 12A. As an example, the bead core 12 of the present embodiment is coated with a coating layer 12A made of a coating resin material, and a single bead cord 12B to which the coating layer 12A is joined is wound multiple times in the tire circumferential direction. It is formed by joining the coating layers 12A of the adjacent bead cords 12B by welding while rotating. In other words, the bead core 12 of this embodiment has a structure in which the outer surface is the coating layer 12A and the bead cord 12B is embedded inside.

Here, as the bead cord 12B, it is preferable to use a monofilament (single wire) such as metal fiber or organic fiber, or a multifilament (twisted wire) obtained by twisting metal fiber or organic fiber. Metal fibers such as steel fibers may be used, and organic fibers such as aromatic polyamide fibers and aliphatic polyamide (nylon) fibers may be used. Metal fibers and organic fibers are not limited to the above fibers. In this embodiment, a steel monofilament is used as the bead cord 12B.

In this embodiment, the covering layer 12A is made of a thermoplastic material having thermoplasticity (for example, thermoplastic resin, thermoplastic elastomer, etc.). The coating layer 12A is made of a coating resin material having a higher tensile modulus than the coating rubber 13B that covers the cords 13A of the carcass ply 14. As shown in FIG.

(Bead filler part)
As shown in FIG. 1, the bead filler portion 18 is arranged between the main body portion 16A and the turnup portion 16B of the carcass 16. As shown in FIG. The bead filler portion 18 of the present embodiment is made of a resin material, and as an example, is made of a thermoplastic material having thermoplasticity (eg, thermoplastic resin, thermoplastic elastomer, etc.). The bead filler portion 18, the bead core 12, and an RFID tag 50, which will be described later, can be integrally formed in advance and sandwiched between the carcass 16 to mold the tire. Before vulcanization of the tire, the bead filler portion 18 has, as an example, as shown in FIG. A shape having a thin portion 18C that is arranged on the outside and elongated in the tire radial direction and that is thinner in the tire width direction than the thick portion 18B can be formed. It is designed so that the bead filler portion 18 will have the shape shown in FIG.

The bead filler portion 18 may be made of the same material as the coating resin material forming the coating layer 12A, or may be made of a different material.

The bead filler portion 18 is made of a resin material having a higher (in other words, harder) tensile modulus than the side rubber layer 24 in order to ensure the bending rigidity of the bead portion 20 . The bead filler portion 18 is made of a resin material having a higher tensile modulus than the coating rubber 13B covering the cords 13A of the carcass 16. As shown in FIG.

The tensile elastic modulus (Young's modulus) of the coating rubber 13B of the carcass 16 is set within a range of 10 to 200 MPa, for example.

The tensile elastic modulus of the resin material forming the coating layer 12A of the bead core 12 is higher than the tensile elastic modulus of the coating rubber 13B, and is set within a range of 100 to 1000 MPa, for example.

The tensile elastic modulus of the resin material forming the bead filler portion 18 is higher than that of the coating rubber 13B, and is set within a range of 100 to 1000 MPa, for example.

The tensile elastic modulus values of the coating layer 12A of the bead core 12 and the bead filler portion 18 are not limited within the above numerical range, and either one may be harder or may be the same.

An inner liner 22 made of rubber is arranged inside the pneumatic tire of the carcass 16 . On the other hand, a side rubber layer 24 is arranged on the outer side of the carcass 16 in the tire width direction. The side rubber layer 24 extends to part of the inner surface of the tire by folding back the radially inner portion of the bead core 12 .

In this embodiment, the bead core 12 , the carcass 16 , the bead filler portion 18 , the inner liner 22 and the side rubber layer 24 constitute a tire case 25 . The tire case 25 is, in other words, a tire skeleton member forming the skeleton of the pneumatic tire 10 .

(belt)
A belt 26 is arranged outside the crown portion of the carcass 16, in other words, outside the carcass 16 in the tire radial direction. The belt 26 of this embodiment is formed flat when viewed in cross section along the tire rotation axis. is in close contact with the outer peripheral surface of the carcass 16 except for a part of. The belt 26 of this embodiment is formed by winding a resin-coated cord 34 in which a plurality of (two in this embodiment) reinforcing cords 30 are coated with a resin 32 .

(layer)
The vicinity of the end portion 26A of the belt 26 in the tire width direction is covered with a strip-shaped layer 38 from the outside in the tire radial direction. The layer 38 preferably covers at least the outermost reinforcing cord 30 in the tire width direction of the belt 26 from the outside in the tire radial direction. covered. Also, the layer 38 extends outward in the tire width direction from the end portion 26A of the belt 26 .

(tread)
A tread 36 made of a rubber material is arranged outside the belt 26 in the tire radial direction. A conventionally known rubber material is used for the tread 36 . A drainage groove 37 is formed in the tread 36 . Further, the pattern of the tread 36 is also conventionally known.

(RFID tag)
An RFID tag 50 is provided on the bead filler portion 18 . The RFID tag 50 is arranged on the inner peripheral portion of the bead filler portion 18 in the tire width direction. As shown in FIG. 3, the RFID tag 50 can be bonded to the thin portion 18C of the bead filler portion 18 before tire vulcanization.

As shown in FIGS. 4A and 4B, the RFID tag 50 has a body chip 52 and an antenna 54 . The body chip 52 includes a processor including a CPU or MPU and a memory capable of storing various information. The antenna 54 extends from the body chip 52 to one side and the other side.

The body chip 52 and the antenna 54 are embedded in a resin coating portion 56 made of a resin material. The resin material forming the resin coating portion 56 is preferably the same type of resin material as the resin material forming the bead filler portion 18 . The embedding in the resin coating portion 56 may be performed by sandwiching between films, or by absorbing the thickness of the main body chip 52 with the resin coating portion 56 having a large thickness. The RFID tag 50 has flexibility in the thickness direction, as shown in FIG. 4(B).

As shown in FIG. 5, the RFID tag 50 is arranged such that the longitudinal direction in which the antenna 54 extends is along the tire circumferential direction. In this way, by arranging the RFID tag 50 along the longitudinal direction along the tire circumferential direction, deformation of the tire case 25 during running is reduced compared to a configuration where the longitudinal direction is arranged along the tire radial direction. It is possible to prevent the antenna 54 from being pulled and detached from the body chip 52 .

(action, effect)
Next, the action and effect of the pneumatic tire 10 of this embodiment will be described.
In the pneumatic tire 10 of the present embodiment, the RFID tag 50 is provided in the bead filler portion 18 made of resin, so compared with the case where the RFID tag is provided in the rubber portion, the RFID tag can be easily attached during manufacturing. can be installed. In particular, by embedding the body chip 52 and the antenna 54 of the RFID tag 50 in the resin coating portion 56 as in the present embodiment, bonding to the bead filler portion 18 made of resin material can be easily performed.

Further, in the present embodiment, the RFID tag 50 is arranged on the inner peripheral portion of the thin portion 18C of the bead filler portion 18 in the tire width direction. Since the thin portion 18C is generally arranged at a position away from the bead core 12, interference between the bead core 12 and the RFID tag 50 during communication can be suppressed. In addition, since the inner peripheral portion in the tire width direction is less likely to be deformed during running than the outer peripheral portion, damage to the RFID tag 50 can be suppressed.

In this embodiment, the RFID tag 50 is arranged on the inner peripheral portion of the thin portion 18C of the bead filler portion 18 in the tire width direction, but it does not necessarily have to be at this position. As shown in FIG. 6, an RFID tag 50 may be arranged on the outer peripheral portion of the thin portion 18C in the tire width direction. Further, as shown in FIG. 7, an RFID tag 50 may be arranged in the intermediate portion of the bead filler portion 18 in the tire width direction.

Further, in the present embodiment, the bead filler portion 18 has the thin portion 18C as the shape before being sandwiched between the carcasses 16 and molded. However, as shown in FIG. A short bead filler portion 18D may be used, and the RFID tag 50 may be arranged on the inner peripheral portion in the tire width direction. In this case, a concave portion may be provided in the bead filler portion 18D to make it flush with the surface of the bead filler portion 18D. Further, as shown in FIG. 8B, a short bead filler portion 18D may be used, and the RFID tag 50 may be arranged on the outer peripheral portion in the tire width direction.

Further, in the present embodiment, the RFID tag 50 is arranged so that its longitudinal direction is along the tire circumferential direction, but the RFID tag 50 may be arranged so that its longitudinal direction is along the tire radial direction.

The structure of the present invention can also be applied to run-flat pneumatic tires whose side portions are reinforced with reinforcing rubber, and can also be applied to pneumatic tires mounted on vehicles other than passenger cars.

10... pneumatic tire, 12... bead core,
13A... cord, 13B... coating rubber, 16... carcass 18... bead filler part, 18B... thick part, 18C... thin part 50... RFID tag, 56... resin coating part

Claims (4)

a carcass in which the cord is coated with coating rubber;
a bead filler portion whose outer surface facing the carcass is formed of a resin harder than the coating rubber;
an RFID tag provided in the bead filler portion;
pneumatic tires with In the cross-sectional shape, the bead filler portion has a thick portion in which the bead core is embedded and is arranged on the inner side in the tire radial direction, and a thin portion that is arranged on the outer side in the tire radial direction and is thinner in the tire width direction than the thick portion. has a part
The pneumatic tire according to claim 1, wherein the RFID tag is arranged in the thin portion of the bead filler portion. The pneumatic tire according to claim 1, wherein the RFID tag is arranged on the inner surface portion of the bead filler portion in the tire width direction. The pneumatic tire according to any one of claims 1 to 3, wherein the RFID tag has a resin coating portion in which a body chip and an antenna are embedded.

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