WO2019230771A1

WO2019230771A1 - Pneumatic tire

Info

Publication number: WO2019230771A1
Application number: PCT/JP2019/021236
Authority: WO
Inventors: 福島　敦
Original assignee: 株式会社ブリヂストン
Priority date: 2018-05-31
Filing date: 2019-05-29
Publication date: 2019-12-05
Also published as: JP2019209751A

Abstract

A pneumatic tire of the present invention has a tread portion provided with: a resin annular body formed of an annular end surface on one side in a tire axis direction of a first annular portion made of resin and an annular end surface on the other side in the tire axis direction of a second annular portion made of resin which are joined together; and a belt which is disposed on the outside in a tire radial direction of the resin annular body, and includes a cord covered with rubber or resin. The annular end surface of the first annular portion of the resin annular body and the annular end surface of the second annular portion of the resin annular body are arranged so as to at least partly overlap each other in the tire radial direction.

Description

Pneumatic tire

The present invention relates to a pneumatic tire.

Conventionally, an inclined belt including a metal cord inclined with respect to the tire circumferential direction on the outer side in the tire radial direction of the carcass disposed across the bead portions, and a circumference including a metal cord extending along the tire circumferential direction. There is known a pneumatic tire in which a belt including a directional belt is disposed.

Patent Document 1 discloses a carcass, an active reinforcing material composed of a single layer of reinforcing elements inclined by 4 ° to 7 ° with respect to the tire circumferential direction, and a flat surface positioned in the central portion of the crown of the carcass. A tire comprising a crown reinforcement comprising a circumferential polymer reinforcement element is disclosed.

Special table 2013-539734 gazette

According to the tire described in Patent Document 1, the weight of the tire can be reduced by using a part of the belt layer including the cord as a flat circumferential polymer reinforcing element as a resin annular body. However, the tire disclosed in Patent Document 1 still has room for improvement in terms of durability and productivity.

Therefore, an object of the present invention is to provide a pneumatic tire including a resin annular body that can improve durability and productivity.

The pneumatic tire as the first aspect of the present invention includes an annular end surface on one side in the tire axial direction of the resin-made first annular portion and an annular end surface on the other side in the tire axial direction of the resin-made second annular portion. A resin annular body formed by joining, and a belt including a cord disposed on the outer side in the tire radial direction of the resin annular body and covered with rubber or resin. The annular end surface of the first annular portion and the annular end surface of the second annular portion of the resin annular body are arranged so that at least a part thereof overlaps in the tire radial direction.

A pneumatic tire according to a second aspect of the present invention includes a resin annular body formed by joining one end surface and the other end surface in the longitudinal direction of a resin strip, and the resin annular body. A belt including a cord disposed on the outer side in the tire radial direction and covered with rubber or a resin, wherein the one end surface of the strip body and the other end surface of the strip body are at least partially Are overlapped in the tire radial direction.

According to the present invention, it is possible to provide a pneumatic tire including a resin annular body that can improve durability and productivity.

1 is a cross-sectional view of a pneumatic tire as an embodiment of the present invention in a cross section parallel to a tire axial direction including a tire center axis. It is a perspective view which shows the resin annular body shown in FIG. It is sectional drawing which shows the tire axial direction cross section of the resin annular body shown in FIG. It is the expanded sectional view which expanded a part of FIG. It is a figure which shows the modification of the cyclic | annular end surface shown in FIG. It is a figure which shows another modification of the cyclic | annular end surface shown in FIG. It is a perspective view which shows the modification of the resin annular body shown in FIG. It is a perspective view which shows the modification of the resin annular body shown in FIG. It is sectional drawing which shows the cross section orthogonal to the tire axial direction of the resin annular body shown to FIG. 7A.

Hereinafter, the pneumatic tire according to the present invention will be described with reference to FIGS. In each figure, the same code | symbol is attached | subjected to the common member and site | part.

Hereinafter, unless otherwise specified, the dimensions, length relationships, positional relationships, etc. of each element are measured in a standard state where a pneumatic tire is mounted on the applicable rim, the specified internal pressure is filled, and no load is applied. And

Here, “applicable rim” is an industrial standard that is effective in the area where pneumatic tires are produced and used. In Japan, JATMA (Japan Automobile Tire Association) JATMA YEAR BOOK, and in Europe, ETRTO (The European) STANDARDS MANUAL of TIRE and RIM Technical Organization, STANDARDS of ETRATO STANDARDS in the applicable size described in YEAR BOOK, etc. of TRA (The Tire and Rim Association, Inc.) in the United States or in the future Refers to Measuring Rim, and Design Rim on TRA's YEAR BOOK (i.e., "Applied Rim" above refers to future sizes in addition to the current size) Examples of “sizes to be described in the future” include the sizes described as “FUTURE DEVELOPMENTS” in the ETRTO 2013 edition). In the case of a size not described in the industry standard, it means a rim having a width corresponding to the bead width of the pneumatic tire.
The “specified internal pressure” refers to the air pressure (maximum air pressure) corresponding to the maximum load capacity of a single wheel in the applicable size / ply rating described in the above JATMA YEAR BOOK, etc. In the case of no size, the air pressure (maximum air pressure) corresponding to the maximum load capacity defined for each vehicle on which the tire is mounted is assumed. In addition, the “maximum load load” described later is defined for each vehicle on which a tire is mounted in the case of a tire maximum load capacity of the standard of JATMA or the like in the tire of an applicable size, or in the case of a size not described in the industrial standard. It means the load corresponding to the maximum load capacity.

FIG. 1 is a view showing a pneumatic tire 1 (hereinafter simply referred to as “tire 1”) as the present embodiment. FIG. 1 is a cross-sectional view of the tire 1 in a cross section parallel to the tire axial direction A including the tire center axis O (the same direction as the tire width direction). Hereinafter, this cross section is referred to as “tire axial direction cross section”. Since the tire 1 shown in FIG. 1 has a symmetric configuration with respect to the tire equator plane CL, only one side in the tire axial direction A is shown, but the configuration is asymmetric with respect to the tire equator plane CL. You can also.

As shown in FIG. 1, the tire 1 includes a tread portion 1a, a pair of sidewall portions 1b extending from both ends of the tread portion 1a in the tire axial direction A to the inside in the tire radial direction B, and each sidewall portion 1b. And a pair of bead portions 1c provided at the inner end in the tire radial direction B. The tire 1 of this embodiment is a tubeless type radial tire for a passenger car. Here, the “tread portion 1a” means a portion sandwiched between the tread ends TE on both sides in the tire axial direction A. Further, the “bead portion 1 c” means a portion where a bead member 3 described later is located in the tire radial direction B. The “sidewall portion 1b” means a portion between the tread portion 1a and the bead portion 1c. The “tread end TE” means a position on the outermost side in the tire axial direction of the ground contact surface in a state where the tire is mounted on the above-described applied rim, the above-mentioned specified internal pressure is filled, and a maximum load is applied. .

The tire 1 includes a bead member 3, a carcass 4, a resin annular body 5, a belt 6, a tread rubber 7, a side rubber 8, and an inner liner 9.

[Bead member 3]
The bead member 3 is embedded in the bead portion 1c. The bead member 3 includes a bead core 3a and a rubber bead filler 3b positioned on the outer side in the tire radial direction B with respect to the bead core 3a. The bead core 3a includes a plurality of bead wires that are covered with rubber. The bead wire is formed of a steel cord. The steel cord can be made of, for example, steel monofilament or stranded wire.

[Carcass 4]
The carcass 4 extends between the pair of bead portions 1c, more specifically between the bead cores 3a of the pair of bead members 3, and extends in a toroidal shape. The carcass 4 has at least a radial structure.

Further, the carcass 4 includes one or more carcass plies 4a in which carcass cords are arranged at an angle of, for example, 75 ° to 90 ° with respect to the tire circumferential direction C (see FIG. 1 and the like). Has been. The carcass ply 4a includes a ply body portion positioned between the pair of bead cores 3a, and a ply folding portion that is folded from the inside to the outside in the tire axial direction A around the bead core 3a at both ends of the ply body portion. ing. A bead filler 3b extending from the bead core 3a to the outer side in the tire radial direction B is disposed between the ply main body portion and the ply folded portion. As the carcass cord constituting the carcass ply 4a, a polyester cord is adopted in this embodiment, but other than this, an organic fiber cord such as nylon, rayon, aramid, or a metal cord such as steel is adopted as necessary. Also good. Also, the number of carcass plies 4a may be two or more.

[Resin ring 5]
FIG. 2 is a perspective view showing the resin annular body 5 shown in FIG. FIG. 3 is a cross-sectional view showing a cross section in the tire axial direction of the resin annular body 5. FIG. 4 is an enlarged cross-sectional view in which a part of FIG. 3 is enlarged. The resin annular body 5 is located on the outer side in the tire radial direction B of the crown portion of the carcass 4 in the tread portion 1a. Further, unlike the belt 6 described later, the resin annular body 5 does not include a cord. That is, no cord is arranged in the resin annular body 5.

2 to 4, the resin annular body 5 is formed by joining a resin-made first annular portion 5a and a resin-made second annular portion 5b. Specifically, as shown in FIGS. 3 and 4, the annular end surface 11 on the one side in the tire axial direction A of the first annular portion 5 a and the annular end surface 12 on the other side in the tire axial direction A of the second annular portion 5 b. And are joined.

As shown in FIGS. 3 and 4, the annular end surface 11 of the first annular portion 5 a of the resin annular body 5 and the annular end surface 12 of the second annular portion 5 b are arranged so that at least a part thereof overlaps with the tire radial direction B. And are joined in this state. Although details will be described later, the entire region of the annular end surface 11 of the first annular portion 5a and the entire region of the annular end surface 12 of the second annular portion 5b of the present embodiment are arranged so as to overlap with the tire axial direction A. It is joined. In addition, although the cyclic | annular end surface 11 of the 1st cyclic | annular part 5a of this embodiment is joined by welding with respect to the cyclic | annular end surface 12 of the 2nd cyclic | annular part 5b, it joins by adhere | attaching with an adhesive agent etc., for example. It is good also as a structure to be made.

More specifically, as shown in FIG. 4, the inner end edge 11 a in the tire radial direction B of the annular end surface 11 of the first annular portion 5 a of the resin annular body 5 corresponds to the second annular portion 5 b of the resin annular body 5. The annular end surface 12 is located on the inner side in the tire radial direction B than the outer end edge 12b in the tire radial direction B. As shown in FIG. 4, the outer end edge 11 b in the tire radial direction B of the annular end surface 11 of the first annular portion 5 a of the resin annular body 5 is formed on the annular end surface 12 of the second annular portion 5 b of the resin annular body 5. It is located outside the inner end edge 12a in the tire radial direction B in the tire radial direction B.

With such a configuration, the thickness of the resin annular body 5 in the tire radial direction B at the joint portion of the first annular portion 5a and the second annular portion 5b of the resin annular body 5 is suppressed and becomes a joint surface. The annular end surface 11 of the first annular portion 5a and the annular end surface 12 of the second annular portion 5b can be secured large. Therefore, the joint strength between the first annular portion 5a and the second annular portion 5b can be increased. In addition, when the thickness of the resin annular body 5 in the tire radial direction B is locally increased at or near the joint portion of the first annular portion 5a and the second annular portion 5b of the resin annular body 5, the above-described joint portion or It can suppress that stress concentration generate | occur | produces in the tread part 1a of the tire 1 in the position of the vicinity. As a result, destruction of the tread portion 1a can be suppressed, and the durability of the tire 1 can be improved.

Further, the resin annular body 5 is formed by joining the annular end surface 11 of the first annular portion 5a and the annular end surface 12 of the second annular portion 5b, so that the resin of this embodiment can be obtained. Even if it is the structure which has the diameter reduction parts 13 and 14 (refer FIG. 3) in the both ends of the tire axial direction A like the annular body 5, the core metal mold | die inside the resin annular body 5 in normal injection molding Can be eliminated in the tire axial direction A, and a plurality of annular parts divided in the tire axial direction A can be formed by using a mold without using a complicated mold, and the annular parts are thereafter The resin annular body 5 can be easily manufactured by joining.

As described above, the tire 1 with improved durability and productivity can be realized by using the resin annular body 5 of the present embodiment.

As the resin constituting the resin annular body 5, for example, a thermoplastic elastomer or a thermoplastic resin can be used, and a resin that is cross-linked by heat or an electron beam or a resin that is cured by thermal rearrangement can also be used. The resin constituting the resin annular body 5 does not include rubber (an organic polymer substance exhibiting rubber elasticity at room temperature).

As thermoplastic elastomers, polyolefin-based thermoplastic elastomer (TPO), polystyrene-based thermoplastic elastomer (TPS), polyamide-based thermoplastic elastomer (TPA), polyurethane-based thermoplastic elastomer (TPU), polyester-based thermoplastic elastomer (TPC) And dynamic crosslinkable thermoplastic elastomer (TPV). Examples of the thermoplastic resin include polyurethane resin, polyolefin resin, vinyl chloride resin, polyamide resin and the like. Further, as the thermoplastic resin, for example, the deflection temperature under load (at the time of 0.45 MPa load) specified in ISO75-2 or ASTM D648 is 78 ° C or more, and the tensile yield strength specified in JIS K7113 is used. A material having a tensile breaking elongation of 50% or more as defined in JIS K7113 and a Vicat softening temperature (Method A) as defined in JIS K7206 of 130 ° C. or more can be used.

In the present embodiment, the annular end surface 11 and the annular end surface 12 are arranged not only in the tire radial direction B but also in the thickness direction of the resin annular body 5. The thickness direction of the resin annular body 5 is a direction orthogonal to a tangent to the inner surface of the resin annular body 5 on the tire inner surface side in a tire axial direction sectional view (see FIG. 1) which is a sectional view along the tire axial direction A. Means.

[Belt 6]
The belt 6 includes a cord disposed on the outer side in the tire radial direction B of the resin annular body 5 in the tread portion 1a and covered with rubber or resin. Specifically, the belt 6 of the present embodiment includes one or more belt layers (one layer in the present embodiment) disposed on the outer side in the tire radial direction B with respect to the crown portion of the carcass 4. More specifically, as shown in FIG. 1, the belt 6 of the present embodiment is constituted by a circumferential belt 6 a composed of only one circumferential belt layer.

The circumferential belt 6a as the belt 6 of the present embodiment is a steel cord as a metal belt cord of 10 ° or less, preferably 5 ° or less, more preferably 2 with respect to the tire circumferential direction C (see FIG. 1 and the like). This is a spiral belt formed by spirally winding around the tire center axis O at an angle of less than or equal to 0 °. More specifically, the circumferential belt 6a as the belt 6 of the present embodiment is a rubber-coated belt formed by a rubber-coated cord made of a cord 10b such as a steel cord covered with a coated rubber 10a. That is, the circumferential belt 6a as the belt 6 is spirally wound around the outer surface of the resin annular body 5 across the reduced

diameter portions

13 and 14 at both ends in the tire axial direction A of the resin annular body 5. It is comprised by the rubber-coated code | cord | chord of the state made.

The rubber-coated cord is wound around the outer surface of the resin annular body 5 in the tire radial direction B while being joined to the outer surface of the resin annular body 5 in the tire radial direction B. In the present embodiment, the rubber-coated cord and the resin annular body 5 are joined by welding the covering rubber 10 a of the rubber-coated cord and the resin annular body 5. However, the covering rubber 10a of the rubber covering cord and the resin annular body 5 are not limited to welding, and may be joined by bonding with an adhesive or the like.

Further, the rubber-coated cords are joined at adjacent portions in the tire axial direction A. In the present embodiment, the portions of the rubber-coated cord that are adjacent to each other in the tire axial direction A are joined together by welding the coated rubber 10a. However, the portions of the rubber-coated cord adjacent to each other in the tire axial direction A are not limited to welding, and may be joined by bonding with an adhesive or the like.

The rubber-coated cord of the present embodiment includes two steel cords, but may be a rubber-coated cord including only one steel cord or a rubber-coated cord including three or more steel cords.

Further, the belt 6 of the present embodiment is a rubber-coated belt, but is not limited to this configuration, and the belt 6 is a resin-coated belt formed from a resin-coated cord made of a cord such as a steel cord coated with a coating resin. It is good. As the coating resin, a resin similar to the resin constituting the resin annular body 5 can be used.

The tensile elastic modulus (specified in JIS K7113: 1995) of the coating resin covering the cord is preferably 50 MPa or more. This is because the belt rigidity can be increased. Moreover, it is preferable that the tensile elasticity modulus of coating resin which coat | covers a cord shall be 1000 Mpa or less. This is because the ride comfort can be maintained well. The coating resin here does not include rubber (an organic polymer substance exhibiting rubber elasticity at room temperature). The resin-coated cord can be formed, for example, by coating a molten coating resin on the outer peripheral side of the cord and solidifying by cooling.

Since the resin has higher rigidity than the weight, the use of the resin-coated belt can improve the tire performance such as steering stability while reducing the weight.

コード Any known material can be used for the cord, for example, the above steel cord can be used. The steel cord can be made of, for example, steel monofilament or stranded wire. Moreover, an organic fiber, carbon fiber, or those strands can also be used for a cord.

The belt 6 has a configuration in which a rubber-coated cord or a resin-coated cord is spirally wound, but a plurality of belts 6 are arranged in the tire axial direction A and are 10 ° or less with respect to the tire circumferential direction C. There is no particular limitation as long as the cord 10b inclined at an angle or extending in parallel is covered with the covering rubber 10a or the covering resin. However, the belt 6 is a spiral belt formed in a state where a rubber-coated cord or a resin-coated cord made of a cord 10b coated with a coating rubber 10a or a coating resin is spirally wound as in the present embodiment. It is preferable that In this way, since the circumferential belt 6a can be formed by the continuous cord 10b having no joint portion in the tire circumferential direction C, the rigidity of the tire 1 in the tire circumferential direction C can be further increased.

[Tread rubber 7 and side rubber 8]
The tread rubber 7 constitutes an outer surface of the tread portion 1a in the tire radial direction B (hereinafter referred to as “tread outer surface”), and the tread outer surface of the present embodiment has a tire circumferential direction C (see FIG. A tread pattern including a circumferential groove 7a extending in the tire axial direction A and a widthwise groove (not shown) extending in the tire axial direction A is formed. The side rubber 8 constitutes an outer surface of the sidewall portion 1b in the tire axial direction A, and is formed integrally with the tread rubber 7 described above.

[Inner liner 9]
The inner liner 9 is laminated on the inner surface of the carcass 4 and is formed of butyl rubber having low air permeability in the present embodiment. The butyl rubber means butyl rubber and halogenated butyl rubber which is a derivative thereof.

Hereinafter, further details of the resin annular body 5 of the present embodiment will be described with reference to FIGS. 1 to 4.

As shown in FIG. 2, the resin annular body 5 of the present embodiment is composed of a first annular portion 5a and a second annular portion 5b. That is, both end portions in the tire axial direction A of the resin annular body 5 of the present embodiment are configured by the first annular portion 5a or the second annular portion 5b. Further, the joint between the annular end surface 11 of the first annular portion 5 a and the annular end surface 12 of the second annular portion 5 b is formed at a position in the tire axial direction A where the outer diameter of the tire 1 is maximum. As shown in FIG. 1, both ends of the resin annular body 5 in the tire axial direction A are located outside the tread end TE in the tire axial direction A. In other words, the resin annular body 5 extends to the outside in the tire axial direction A from the tread end TE.

As shown in FIGS. 1 and 2, in the resin annular body 5 of the present embodiment, the end portion on the other side in the tire axial direction A of the first annular portion 5 a (in the present embodiment, the annular end surface 11 in the tire axial direction A is The end portion on the opposite side to a certain side) is a reduced diameter portion 13 that decreases in diameter so as to approach the tire center axis O toward the outer end in the tire axial direction A. Further, as shown in FIG. 2, in the resin annular body 5 of the present embodiment, there is an end portion on one side of the second annular portion 5b in the tire axial direction A (in the present embodiment, there is an annular end surface 12 in the tire axial direction A). The end portion on the opposite side to the side) is a reduced diameter portion 14 that decreases in diameter so as to approach the tire center axis O toward the outer end in the tire axial direction.

That is, both end portions in the tire axial direction A of the resin annular body 5 of the present embodiment are constituted by the reduced

diameter portions

13 and 14 that are reduced in diameter so as to approach the tire center axis O toward the outer end in the tire axial direction A. ing. By providing such reduced

diameter portions

13 and 14, the tread end TE (see FIG. 1) is compared with the case where the reduced

diameter portions

13 and 14 are not provided and the resin annular body has a uniform inner diameter and outer diameter. It is possible to suppress the local contact pressure from locally increasing at a position in the vicinity, and to suppress the occurrence of uneven wear on the outer surface of the tread. The reduced

diameter portions

13 and 14 are reduced in diameter so as to substantially follow the carcass 4 in a cross-sectional view along the tire axial direction A.

More specifically, as shown in FIG. 2, the outer surface in the tire radial direction B of the resin annular body 5 of the present embodiment is a barrel shape, and the outer surfaces of the reduced

diameter portions

13 and 14 of the present embodiment are convex shapes. It is a curved surface that bends in a straight line. Thus, by making the outer surfaces of the diameter-reduced

portions

13 and 14 in the tire radial direction B convex curved surfaces, local fluctuations in the contact pressure are caused at positions near the tread end TE (see FIG. 1). Can be suppressed more.

As shown in FIG. 4, in the present embodiment, the annular end surface 11 of the first annular portion 5 a and the annular end surface 12 of the second annular portion 5 b of the resin annular body 5 are connected to the tire shaft of the resin annular body 5. In the tire axial direction sectional view which is a sectional view along the direction A, the inclined surface is inclined with respect to the tire axial direction A and the tire radial direction B.

In the cross-sectional view in the tire axial direction, the inclination angle θ1 of the annular end surface 11 of the first annular portion 5a with respect to the tire axial direction A is preferably close to 0 ° along the tire axial direction A from the viewpoint of expanding the joint surface. . Therefore, the inclination angle θ1 of the annular end surface 11 of the first annular portion 5a with respect to the tire axial direction A is preferably 45 ° or less, and more preferably 30 ° or less. The same applies to the inclination angle θ2 of the annular end surface 12 of the second annular portion 5b with respect to the tire axial direction A.

Further, as shown in FIG. 4, the entire region of the annular end surface 11 of the first annular portion 5 a of the present embodiment is in a position overlapping with the entire region of the second annular portion 5 b in the tire axial direction A. That is, the annular end surfaces 11 and 12 are not exposed on the inner surface side and the outer surface side in the tire radial direction B of the resin annular body 5. And the 1st annular part 5a and the 2nd annular part 5b are joined by welding between the annular end surface 11 of the 1st annular part 5a, and the annular end surface 12 of the 2nd annular part 5b. As described above, the annular end surfaces 11 and 12 are configured to include the inclined surface, whereby a large joint surface can be secured.

In addition, although the annular end surfaces 11 and 12 of this embodiment are comprised only by the inclined surface inclined with respect to the tire axial direction A, in addition to an inclined surface, the surface etc. extended in parallel with the tire radial direction B etc. An annular end face may be included. However, it is preferable to use only an inclined surface that is inclined with respect to the tire axial direction A, such as the annular end surfaces 11 and 12 of the present embodiment, because a large bonding surface can be ensured with a simple configuration.

Here, the first annular portion 5a of the present embodiment has a substantially uniform thickness at positions excluding the position of the annular end surface 11. The thickness of the first annular portion 5a of the present embodiment is set from a range of 0.3 mm to 1.0 mm, for example. The second annular portion 5b of the present embodiment also has a substantially uniform thickness at positions other than the position of the annular end surface 12. The thickness of the 2nd annular part 5b of this embodiment is set as the thickness substantially equal to the 1st annular part 5a.

FIG. 5 is a view showing a modification of the annular end faces 11 and 12 shown in FIG. An annular end surface 111 of the first annular portion 5a illustrated in FIG. 5 includes an inclined surface that is inclined with respect to the tire axial direction A in the tire axial direction sectional view that is a sectional view along the tire axial direction A.

More specifically, the annular end surface 111 of the first annular portion 5a shown in FIG. 5 has a first inclined surface 120a that is inclined with respect to the tire axial direction A and a tire axial direction A in the tire axial sectional view. A second inclined surface 120b inclined to the opposite side of the first inclined surface 120a. The first inclined surface 120a and the second inclined surface 120b form a top portion 121 of the annular end surface 111 by ridgelines intersecting each other.

Further, the annular end surface 112 of the second annular portion 5b shown in FIG. 5 includes an inclined surface that is inclined with respect to the tire axial direction A in the tire axial direction sectional view that is a sectional view along the tire axial direction A.

More specifically, the annular end surface 112 of the second annular portion 5b shown in FIG. 5 has a first inclined surface 122a that is inclined with respect to the tire axial direction A and a tire axial direction A in the tire axial sectional view. A second inclined surface 122b inclined to the opposite side of the first inclined surface 122a. The first inclined surface 122a and the second inclined surface 122b form a top portion 123 of the annular end surface 112 by ridge lines intersecting each other.

The first inclined surface 120a of the annular end surface 111 of the first annular portion 5a is disposed to face the second inclined surface 122b of the annular end surface 112 of the second annular portion 5b so as to overlap in the tire radial direction B. The first inclined surface 120a of the annular end surface 111 of the first annular portion 5a and the second inclined surface 122b of the annular end surface 112 of the second annular portion 5b are welded.

Moreover, since the 2nd inclined surface 120b is provided in the annular end surface 111 of the 1st annular part 5a shown in FIG. 5, the tire radial direction B of the resin annular body 5 of the junction part of the annular end surfaces 111 and 112 is provided. A groove 124 having a V-shaped cross section extending in the tire circumferential direction C, which is defined by the second inclined surface 120b of the annular end surface 111 and the second inclined surface 122b of the annular end surface 112, is formed on the outer surface side. Therefore, the bulging portion 125 that melts and bulges when the annular end surface 111 of the first annular portion 5 a and the annular end surface 112 of the second annular portion 5 b are welded can be received in the groove 124. As a result, when the annular end surface 111 of the first annular portion 5a and the annular end surface 112 of the second annular portion 5b are welded, the bulging portion 125 generated by melting the annular end surfaces 111 and 112 becomes the resin ring after welding. Protruding to the outer surface side of the body 5 can be suppressed. As a result, compared with the configuration of the annular end surfaces 11 and 12 shown in FIG. 4, the stress concentration of the tire can be further suppressed, and therefore the durability of the tire can be further enhanced.

Furthermore, since the first inclined surface 122a is provided on the annular end surface 112 of the second annular portion 5b shown in FIG. 5, the annular end surface is formed on the inner surface side of the resin annular body 5 at the joint portion of the annular end surfaces 111 and 112. A groove 126 having a V-shaped cross section extending in the tire circumferential direction C and formed by a first inclined surface 120a of 111 and a first inclined surface 122a of the annular end surface 112 is formed. Therefore, the bulging portion 127 that melts and bulges when the annular end surface 111 of the first annular portion 5 a and the annular end surface 112 of the second annular portion 5 b are welded can be received in the groove 126. As a result, when the annular end surface 111 of the first annular portion 5a and the annular end surface 112 of the second annular portion 5b are welded, the bulging portion 127 generated by the melting of the annular end surfaces 111 and 112 becomes the resin ring after welding. Protruding to the inner surface side of the body 5 can be suppressed. As a result, compared with the configuration of the annular end surfaces 11 and 12 shown in FIG. 4, the stress concentration of the tire can be further suppressed, and therefore the durability of the tire can be further enhanced.

FIG. 6 is a view showing another modification of the annular end faces 11 and 12 shown in FIG. An annular end surface 211 of the first annular portion 5a shown in FIG. 6 has a joint receiving surface 228 extending along the tire axial direction A of the resin annular body 5 in a cross-sectional view of the resin annular body 5 along the tire axial direction A. Including staircase.

More specifically, the annular end surface 211 of the first annular portion 5a shown in FIG. 6 is continuous with the joint receiving surface 228 and one end of the joint receiving surface 228 in the tire axial direction A and extends inward in the tire radial direction B. A proximal end surface 229 that is present, and a distal end surface 230 that is continuous with the other end of the joint receiving surface 228 in the tire axial direction A and extends outward in the tire radial direction B.

Further, the annular end surface 212 of the second annular portion 5b shown in FIG. 6 is a joint receiving surface that extends along the tire axial direction A of the resin annular body 5 in a cross-sectional view along the tire axial direction A of the resin annular body 5. This is a step surface including H.231.

More specifically, the annular end surface 212 of the second annular portion 5b shown in FIG. 6 is continuous with the joint receiving surface 231 and one end of the joint receiving surface 231 in the tire axial direction A and extends outward in the tire radial direction B. And a distal end surface 233 that is continuous with the other end in the tire axial direction A of the joint receiving surface 231 and extends inward in the tire radial direction B.

The joint receiving surface 228 of the annular end surface 211 of the first annular portion 5a is disposed to face the joint receiving surface 231 of the annular end surface 212 of the second annular portion 5b so as to overlap in the tire radial direction B. The joint receiving surface 228 of the annular end surface 211 of the first annular portion 5a and the joint receiving surface 231 of the annular end surface 212 of the second annular portion 5b are welded together.

As shown in FIG. 6, it is good also as the annular end surfaces 211 and 212 which are not provided with the inclined surface which inclines with respect to the tire axial direction A in the cross sectional view along the tire axial direction A. Even with such a configuration, a large joint surface can be secured.

Further, as shown in FIG. 6, a gap is formed between the distal end surface 230 of the annular end surface 211 of the first annular portion 5a and the proximal end surface 232 of the annular end surface 212 of the second annular portion 5b. This gap forms a groove 234 having a rectangular cross section that opens to the outer surface side in the tire radial direction B of the resin annular body 5 and extends in the tire circumferential direction C. Therefore, the bulging portion 235 that melts and bulges when the annular end surface 211 of the first annular portion 5a and the annular end surface 212 of the second annular portion 5b are welded can be received in the groove 234. As a result, when the annular end surface 211 of the first annular portion 5a and the annular end surface 212 of the second annular portion 5b are welded, the bulging portion 235 generated by melting the annular end surfaces 211 and 212 becomes the resin ring after welding. Protruding to the outer surface side of the body 5 can be suppressed. As a result, compared with the configuration of the annular end surfaces 11 and 12 shown in FIG. 4, the stress concentration of the tire can be further suppressed, and therefore the durability of the tire can be further enhanced.

Furthermore, as shown in FIG. 6, a gap is formed between the base end surface 229 of the annular end surface 211 of the first annular portion 5a and the distal end surface 233 of the annular end surface 212 of the second annular portion 5b. This gap constitutes a rectangular cross-sectional groove 236 that opens to the inner surface side of the resin annular body 5 and extends in the tire circumferential direction C. Therefore, the bulging portion 237 that melts and bulges when the annular end surface 211 of the first annular portion 5a and the annular end surface 212 of the second annular portion 5b are welded can be received in the groove 236. As a result, when the annular end surface 211 of the first annular portion 5a and the annular end surface 212 of the second annular portion 5b are welded, the bulging portion 237 generated by melting the annular end surfaces 211 and 212 becomes the resin ring after welding. Protruding to the inner surface side of the body 5 can be suppressed. As a result, compared with the configuration of the annular end surfaces 11 and 12 shown in FIG. 4, the stress concentration of the tire can be further suppressed, and therefore the durability of the tire can be further enhanced.

7A and 7B are perspective views showing modifications of the resin annular body 5. Specifically, FIG. 7A is a diagram illustrating a resin annular body 305 as a modification of the resin annular body 5. FIG. 7B is a view showing a resin annular body 405 as a modified example of the resin annular body 5. The resin annular body 305 shown in FIG. 7A and the resin annular body 405 shown in FIG. 7B are formed by forming one strip body in an annular shape and joining the end faces to each other as compared with the resin annular body 5 shown in FIGS. It differs in that it is formed.

The resin annular body 305 shown in FIG. 7A is formed by joining one end face 339 and the other end face 340 in the longitudinal direction of a resin strip 338. That is, the longitudinal direction of the strip body 338 is the same direction as the tire circumferential direction C.

At least a part of one end surface 339 of the strip body 338 and the other end surface 340 of the strip body 338 are arranged so as to overlap in the tire radial direction B. In the present embodiment, at least a part of one end surface 339 of the strip body 338 and the other end surface 340 of the strip body 338 are arranged so as to overlap in the thickness direction of the strip body 338.

FIG. 8 is a cross-sectional view showing a cross section of the resin annular body 305 shown in FIG. 7A perpendicular to the tire axial direction A (the same direction as the tire width direction) of the strip body 338. As shown in FIG. 8, the inner end edge 339a in the tire radial direction B of one end surface 339 of the strip body 338 is more in the tire radial direction than the outer end edge 340b in the tire radial direction B of the other end surface 340 of the strip body 338. Located inside B. Further, the outer end edge 339b in the tire radial direction B of one end surface 339 of the strip body 338 is located outside the inner end edge 340a in the tire radial direction B of the other end surface 340 of the strip body 338 in the outer side in the tire radial direction B. To do.

By adopting such a configuration, compared to the resin annular body 5 formed by joining a plurality of members shown in FIGS. 1 to 6 (joining two annular portions in FIGS. 1 to 6), The resin annular body 305 can be formed with one member, and the same effect can be obtained.

Further, the resin annular body 405 shown in FIG. 7B is different in the configuration of the joint portion from the resin annular body 305 shown in FIG. 7A, but the other configurations are the same. Specifically, one end surface 339 and the other end surface 340 of the resin annular body 305 shown in FIG. 7A extend along the tire axial direction A, whereas the strip body of the resin annular body 405 shown in FIG. 7B. One end surface 439 and the other end surface 440 of 438 extend inclined with respect to the tire axial direction A when the resin annular body 405 is viewed from the outside in the tire radial direction B. By setting it as such a structure, durability of a tire can be improved more.

As for the resin annular body 305 shown in FIG. 7A, as in the resin annular body 5 shown in FIG. 1, at least one end portion in the tire axial direction A extends toward the outer end in the tire axial direction A. It is a reduced diameter part which reduces in diameter so that it may approach. More specifically, both end portions in the tire axial direction A of the resin annular body 305 shown in FIG. 7A are constituted by reduced

diameter portions

313 and 314. The outer surface in the tire radial direction of each of the reduced

diameter portions

313 and 314 is a curved surface that curves into a convex shape.

7B, as in the case of the resin annular body 5 shown in FIG. 1, at least one end portion in the tire axial direction A is the tire center axis O as it goes toward the outer end in the tire axial direction A. It is a reduced diameter part which reduces in diameter so that it may approach. More specifically, both end portions in the tire axial direction A of the resin annular body 405 shown in FIG. 7B are constituted by reduced

diameter portions

413 and 414. The outer surface in the tire radial direction B of each of the reduced

diameter portions

413 and 414 is a curved surface that curves into a convex shape.

Note that the shapes of the annular end surfaces 11 and 12 shown in FIG. 4, the shapes of the annular end surfaces 111 and 112 shown in FIG. 5, and the shapes of the annular end surfaces 211 and 212 shown in FIG. The end face 339 and the other end face 340 can be adopted as shapes in a cross-sectional view (see FIG. 8) perpendicular to the tire axial direction A (the same direction as the tire width direction) of the strip body 338, and the same effect can be obtained. Can do. Further, the shape of the annular end surfaces 11 and 12 shown in FIG. 4, the shape of the annular end surfaces 111 and 112 shown in FIG. 5, and the shape of the annular end surfaces 211 and 212 shown in FIG. The end face 439 and the other end face 440 can be adopted as shapes in a cross-sectional view orthogonal to the tire axial direction A (the same direction as the tire width direction) of the strip body 438, and similar effects can be obtained.

The pneumatic tire according to the present invention is not limited to the specific configurations shown in the above-described embodiments and modifications, and various modifications and changes can be made without departing from the scope of the claims. For example, the resin annular body shown in FIGS. 1 to 7 has a barrel-shaped outer shape, but there are reduced diameter portions only at both ends in the tire axial direction A, and the central portion in the tire axial direction A has an inner diameter and It is good also as a resin annular body comprised by the cylinder part with a uniform outer diameter.

The present invention relates to a pneumatic tire.

1: pneumatic tire, 1a: tread portion, 1b: sidewall portion, 1c: bead portion, 3: bead member, 3a: bead core, 3b: bead filler, 4: carcass, 4a: carcass ply, 5, 305, 405: Resin annular body, 5a: first annular portion, 5b: second annular portion, 6: belt, 6a: circumferential belt, 7: tread rubber, 7a: circumferential groove, 8: side rubber, 9: inner liner, 10a: Covered rubber, 10b: cord, 11, 111, 211: annular end surface of the first annular portion, 11a: inner edge of the annular end surface of the first annular portion, 11b: outer edge of the annular end surface of the first annular portion, 12 112a, 212: the annular end surface of the second annular portion, 12a: the inner edge of the annular end surface of the second annular portion, and 12b: the outer end of the annular end surface of the second annular portion. , 13, 14, 313, 314, 413, 414: reduced diameter portion, 120a: first inclined surface of the annular end surface of the first annular portion, 120b: second inclined surface of the annular end surface of the first annular portion, 121: first The top of the annular end surface of one annular portion, 122a: the first inclined surface of the annular end surface of the second annular portion, 122b: the second inclined surface of the annular end surface of the second annular portion, 123: the top of the annular end surface of the first annular portion 124, 126: groove, 125, 127: bulging portion, 228: joint receiving surface of the annular end surface of the first annular portion, 229: proximal end surface of the annular end surface of the first annular portion, 230: annular shape of the first annular portion 231: base end surface of the annular end surface of the second annular portion, 233: distal end surface of the annular end surface of the second annular portion, 234, 236: grooves , 235, 237: bulge part, 3 8, 438: Strip body, 339, 439: One end face of the strip body, 339a: Inner edge of one end face of the strip body, 339b: Outer edge of one end face of the strip body, 340, 440: Strip body 340a: inner end edge of the other end face of the strip body, 340b: outer edge of the other end face of the strip body, A: tire axial direction, B: tire radial direction, C: tire circumferential direction (strip Body longitudinal axis), O: tire center axis, CL: tire equatorial plane, TE: tread edge, θ1, θ2: inclination angle of annular end face

Claims

A resin ring formed by joining an annular end surface on one side in the tire axial direction of the first annular portion made of resin and an annular end surface on the other side in the tire axial direction of the second annular portion made of resin. Body,
A belt including a cord that is disposed on the outer side in the tire radial direction of the resin annular body and is covered with rubber or resin, and is provided in the tread portion,
The annular end surface of the first annular portion of the resin annular body and the annular end surface of the second annular portion of the resin annular body are arranged such that at least a part thereof is overlapped in the tire radial direction. tire.
2. The pneumatic tire according to claim 1, wherein at least one end portion of the resin annular body in the tire axial direction is a reduced diameter portion that is reduced in diameter so as to approach the tire central axis line toward an outer end in the tire axial direction. .
The pneumatic tire according to claim 2, wherein an outer surface of the reduced diameter portion in a tire radial direction is a curved surface curved in a convex shape.
Each of the annular end surface of the first annular portion and the annular end surface of the second annular portion that are joined in the resin annular body is the resin annular body in a sectional view along the tire axial direction of the resin annular body. The pneumatic tire according to any one of claims 1 to 3, including an inclined surface that is inclined with respect to the tire axial direction.
Each of the annular end surface of the first annular portion and the annular end surface of the second annular portion that are joined in the resin annular body is the resin annular body in a sectional view along the tire axial direction of the resin annular body. The pneumatic tire according to any one of claims 1 to 3, wherein the pneumatic tire is a stepped surface including a joint receiving surface extending along the tire axial direction.
A resin annular body formed by joining one end face and the other end face in the longitudinal direction of the resin strip; and
A belt including a cord disposed on the outer side in the tire radial direction of the resin annular body and covered with rubber or resin,
A pneumatic tire in which at least a part of the one end surface of the strip body and the other end surface of the strip body are arranged to overlap each other in the tire radial direction.
7. The pneumatic tire according to claim 6, wherein at least one end portion of the resin annular body in the tire axial direction is a reduced diameter portion that decreases in diameter so as to approach the tire central axis line toward the outer end in the tire axial direction. .
The pneumatic tire according to claim 7, wherein an outer surface of the reduced diameter portion in a tire radial direction is a curved surface curved in a convex shape.
Each of the one end surface and the other end surface of the strip body joined among the resin annular bodies is inclined with respect to the longitudinal direction of the strip body in a cross-sectional view orthogonal to the tire axial direction of the strip body. The pneumatic tire according to any one of claims 6 to 8, comprising an inclined surface.
Each of the one end face and the other end face of the strip body joined among the resin annular bodies extends along the longitudinal direction of the strip body in a cross-sectional view orthogonal to the tire axial direction of the strip body. The pneumatic tire according to any one of claims 6 to 8, which is a stepped surface including an existing joint receiving surface.
The one end face and the other end face of the strip body joined among the resin annular bodies are inclined with respect to the tire axial direction in a plan view of the resin annular body viewed from the outside in the tire radial direction. The pneumatic tire according to any one of claims 6 to 10, wherein the pneumatic tire extends.