阅读说明：本技术 斜交轮胎 (Cross-ply ) 是由 元满隆昌 于 2017-12-26 设计创作，主要内容包括：本发明提供一种能提高耐久性能的斜交轮胎。斜交轮胎具备：一对胎圈芯；配置在一对胎圈芯每个的轮胎径向外侧的胎边芯；以及架设在一对胎圈芯之间,并且包入胎圈芯以及胎边芯且端部被卷回而卡定的胎体层,其中,在轮胎子午线方向的剖面,在供斜交轮胎嵌入的轮辋的凸缘的高度的0.9倍以上且1.6倍以下的范围的任意位置处,胎体层的轮胎宽度方向最内侧的帘线的弯曲形状为向轮胎宽度方向的外侧凸出,并且,在轮胎子午线方向的剖面,在凸缘的高度的1.1倍以上且1.6倍以下的范围的任意位置处,胎体层的轮胎宽度方向最外侧的帘线的弯曲形状为向轮胎宽度方向的外侧凸出。(The present invention provides a kind of cross-ply that can improve endurance quality.Cross-ply has: a pair of bead core；Configure the bead-core in each tire radial outside of a pair of bead core；And it is erected between a pair of bead core, and it is packed in bead core and bead-core and end body piles locking by rollback, wherein, section in tyre equatorial direction, in any position of 0.9 times or more and 1.6 times range below of the height of the flange for the wheel rim being embedded in for cross-ply, the curved shape of the innermost cord of the tire width direction of body piles is to protrude to the outside of tire width direction, and, section in tyre equatorial direction, in any position of 1.1 times or more and 1.6 times ranges below of the height of flange, the curved shape of the outermost cord of the tire width direction of body piles is to protrude to the outside of tire width direction.)

1. a kind of cross-ply, has: a pair of bead core；Configuration is in the respective tire radial outside of the pair of bead core Bead-core；And it is erected between the pair of bead core, and be packed in the bead core and the bead-core and end quilt Rollback and locking body piles, wherein

Section in tyre equatorial direction, at 0.9 times or more of the height of the flange of the wheel rim for cross-ply insertion And any position of 1.6 times of ranges below, the curved shape of the innermost cord of the tire width direction of the body piles To be protruded to the outside of tire width direction, also,

Section in tyre equatorial direction, the height of the flange 1.1 times or more and 1.6 times ranges below it is any At position, the curved shape of the outermost cord of the tire width direction of the body piles is convex to the outside of tire width direction Out.

2. cross-ply according to claim 1, wherein

Section in tyre equatorial direction, at 1.5 times of the height of the flange of position, the tire of the body piles is wide Spend the radius of curvature R 1 and the maximum of the maximum height position from the body piles to the body piles of the innermost cord in direction The innermost curtain of tire width direction of the body piles at 1/3 position of the length along tire radial direction of width position The ratio between curvature of a curve radius R3 R1/R3 is 0.5 or more and 1.0 or less.

3. cross-ply according to claim 1 or 2, wherein

Section in tyre equatorial direction, the thickness of the tire width direction of the bead-core is with from the bead core direction Tire radial outside and successively decrease.

4. cross-ply according to any one of claim 1 to 3, wherein

Including the multipair bead core,

It respectively correspondingly include multiple bead-cores and the body piles with the bead core,

Multiple body piles are packed in the bead core and the bead-core corresponding with the bead core and respectively by rollbacks And it is locking,

Section in tyre equatorial direction, the height of the highest bead-core of height of tire radial direction is in multiple bead-cores 0.17 times or more and 0.23 times or less of carcass section height.

5. cross-ply according to claim 4, wherein

It further include other body piles of covering multiple body piles corresponding with the multipair bead core.

6. cross-ply according to any one of claim 1 to 5, wherein

Section in tyre equatorial direction, at 1.5 times of the height of the flange of position,

The radius of curvature R 1 of the innermost cord of the tire width direction of the body piles and the tyre width side of the body piles The ratio between radius of curvature R 2 to outermost cord R1/R2 is 1.0 or more and 1.8 or less.

7. cross-ply according to any one of claim 1 to 6, wherein

Section in tyre equatorial direction, at 1.5 times of the height of the flange of position,

The radius of curvature R 1 and tyre contour outline curvature of a curve radius R4 of the innermost cord of the tire width direction of the body piles The ratio between R1/R4 be 2.5 or less.

8. cross-ply according to any one of claim 1 to 7, wherein

The piece number of the respective included carcass of the body piles is 4 or more and 8 or less.

9. cross-ply according to any one of claim 1 to 8, wherein

The angle of the cord of the innermost body piles of tire width direction relative to tire be circumferentially 25 degree or more and 45 degree with Under.

10. cross-ply according to any one of claim 1 to 9, wherein

Section in tyre equatorial direction, the innermost cord of the tire width direction of the body piles have the Curved Shape becomes the inflection point protruded to the outside of tire width direction to the inside of tire width direction protrusion,

The inflection point is located at 0.25 times or more of the height of the flange and 0.75 times of range below.

11. cross-ply according to any one of claim 1 to 10, wherein

Section in tyre equatorial direction, the outermost cord of the tire width direction of the body piles have the Curved Shape becomes the inflection point protruded to the outside of tire width direction to the inside of tire width direction protrusion,

The inflection point is located at 0.60 times or more of the height of the flange and 1.15 times of ranges below.

Technical field

The present invention relates to a kind of cross-plies.

Background technique

In general, the load of industrial vehicle tire is high and is set to high pressure.For example, gantry for being used in bay etc. The cross-ply of the heavy load of crane (gantry crane) etc. is high load capacity setting and high center of gravity.Therefore, such oblique Tire is handed over to be easy by partial load, it some times happens that the vehicle as caused by excessive deflection shakes or tire fault.However, due to vehicle The problem of taking turns intensity, operational administrative, further high pressure are set at difficult situation.

Furthermore patent document 1 discloses radial.In the radial of patent document 1, in order to improve tyre bead Bead part, curvature of casing ply etc. are set as value appropriate by the durability in portion.

Summary of the invention

Problems to be solved by the invention

In heavy load cross-ply, as the bring torque of vehicle evolution in recent years improves, to the tire around tyre bead The load of body is in ascendant trend.In particular, the low WB of used flat ratio (the Wide Base: wide under the conditions of crossing load Base) size cross-ply in, it some times happens that cords break, casing ply separation (ply separation).Cords break (Cord Broken Up, hereinafter referred to as CBU) is casing ply at the innermost point of tire axial and the steel wire of bead core End forced contact is wound so that being broken.CBU is by the excessive drawing of the tyre bead and carcass of the inner surface side of tire width direction It stretches and occurs.

Casing ply separation is bead-core and contacts the stripping damage of the carcass of setting with the bead-core.Casing ply separation be by Close to the inner surface side body piles of equatorial plane and far from the outer surface side carcass of equatorial plane on tire width direction Layer between deformation and occur.

Patent document 1 discloses a kind of passenger car tire and is related to the technology of radial.Therefore, by patent document 1 The cross-ply that disclosed technology is applied to heavy load is inappropriate.

The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a kind of excessive drawings that can inhibit body piles It stretches, improves the cross-ply of endurance quality.

Technical solution

To solve the above-mentioned problems, purpose is realized, the cross-ply of some scheme of the invention is that one kind has: a pair of of tire Enclose core；Configure the bead-core in the respective tire radial outside of the pair of bead core；And it is erected at the pair of bead core Between, and it is packed in the cross-ply of the bead core and the bead-core and end body piles locking by rollback, In, the section in tyre equatorial direction, at 0.9 times or more of height of the flange of the wheel rim for cross-ply insertion and The curved shape of any position of 1.6 times of ranges below, the innermost cord of the tire width direction of the body piles is It is protruded to the outside of tire width direction, also, the section in tyre equatorial direction, at 1.1 times of the height of the flange Above and any position of 1.6 times of ranges below, the bending of the outermost cord of the tire width direction of the body piles Shape is to protrude to the outside of tire width direction.

Moreover it is preferred that the section in tyre equatorial direction, at 1.5 times of the height of the flange of position, The radius of curvature R 1 of the innermost cord of the tire width direction of the body piles and the maximum height position from the body piles The tire of the body piles to 1/3 position of the length along tire radial direction of the maximum width position of the body piles The ratio between the radius of curvature R 3 of the innermost cord of width direction R1/R3 is 0.5 or more and 1.0 or less.

Preferably, in the section in tyre equatorial direction, the thickness of the tire width direction of the bead-core with from The bead core successively decreases towards tire radial outside.

It preferably, including the multipair bead core, respectively correspondingly include multiple bead-cores with the bead core With the body piles, multiple body piles are packed in the bead core and the bead-core corresponding with the bead core simultaneously respectively And, section in tyre equatorial direction locking by rollback, the highest tire of height of tire radial direction in multiple bead-cores The height of side core is 0.17 times of carcass section height or more and 0.23 times or less.

It preferably, further include other carcasses of covering multiple body piles corresponding with the multipair bead core Layer.

Preferably, described at 1.5 times of the height of the flange of position in the section in tyre equatorial direction The radius of curvature R 1 of the innermost cord of the tire width direction of body piles and the tire width direction outermost of the body piles The ratio between the radius of curvature R 2 of cord R1/R2 be 1.0 or more and 1.8 or less.

Preferably, described at 1.5 times of the height of the flange of position in the section in tyre equatorial direction The ratio between the radius of curvature R 1 of the innermost cord of the tire width direction of body piles and tyre contour outline curvature of a curve radius R4 R1/R4 It is 2.5 or less.

Preferably, the piece number of the respective included carcass of the body piles is 4 or more and 8 or less.

It preferably, is circumferentially 25 degree relative to tire in the angle of the cord of the innermost body piles of tire width direction Above and 45 degree or less.

Preferably, in the section in tyre equatorial direction, the innermost cord of the tire width direction of the body piles Become the inflection point protruded to the outside of tire width direction to the inside of tire width direction protrusion with the curved shape, The inflection point is located at 0.25 times or more of the height of the flange and 0.75 times of range below.

Preferably, in the section in tyre equatorial direction, the outermost cord of the tire width direction of the body piles Become the inflection point protruded to the outside of tire width direction to the inside of tire width direction protrusion with the curved shape, The inflection point is located at 0.60 times or more of the height of the flange and 1.15 times of ranges below.

Beneficial effect

Cross-ply according to the present invention, by by the innermost cord of the tire width direction of body piles and outermost Cord curved shape be set as to the outside of tire width direction protrude, endurance quality can be improved.

Detailed description of the invention

Fig. 1 is the sectional view of the meridian direction of the cross-ply of present embodiment.

Fig. 2 is a part for omitting Fig. 1 and the figure that shows.

Fig. 3 is the sectional view in the tyre equatorial direction of the construction near the bead part of the cross-ply of explanatory diagram 1.

Fig. 4 is the figure of effect of the cross-ply of explanatory diagram 1 in high load capacity.

Fig. 5 is the sectional view for illustrating the tyre equatorial direction of the construction near the bead part of the cross-ply of comparative example.

Fig. 6 is the figure of effect of the cross-ply of explanatory diagram 5 in high load capacity.

Specific embodiment

Hereinafter, being based on attached drawing, the embodiment of cross-ply of the invention is described in detail.The present invention is not by this The restriction of embodiment.In addition, including that those skilled in the art can replace and be easy to set in the constituent element of the embodiment The element or substantially the same element changed.Multiple improvements described in the embodiment can be for art technology Any combination is carried out for personnel in apparent range.It should be noted that in the explanation of following figure, to other Scheme identical or same composition part and mark identical symbol, simply or the description thereof will be omitted.

The cross-ply of embodiments of the present invention is illustrated.Fig. 1 is the meridian of the cross-ply of present embodiment The sectional view in line direction.Fig. 1 shows the sectional view of tire radial direction.Fig. 2 is a part for omitting Fig. 1 and the figure that shows.In addition, As an example of cross-ply, figures 1 and 2 show that the cross-ply of heavy load.

In Fig. 1, the section in tyre equatorial direction refers to, to include the plane cutting of tire rotary shaft (illustration omitted) Section when tire.In addition, symbol CL is equatorial plane, refer to that the central point from the tire in tire rotary axis direction passes through And the plane vertical with tire rotary shaft.In addition, tire radially refers to the direction vertical with tire rotary shaft.Tire width direction Refer to the direction parallel with tire rotary shaft, tire circumferentially refers to around the direction of tire rotary shaft.

In Fig. 1, the cross-ply 1 of present embodiment has the ring-shaped structure centered on tire rotary shaft.This implementation The cross-ply 1 of mode have pair of right and left bead part 2,2 be embedded with respectively multiple (in Fig. 1 for 3) bead core 3a, 3b,3c.In Fig. 1, regulation wheel rim is represented by dashed line.Cross-ply 1 shown in FIG. 1 shows the state for not carrying out wheel rim assembling Shape, not to wheel rim 30 carry out wheel rim assembling in the case where, the position of the end of bead part 2,2 is more leaned on than the position of diagram Tire radial direction inner side.

Regulation wheel rim refers to that as defined in JATMA " applicable wheel rim ", " Design Rim (take turns by design as defined in TRA Rim) " or as defined in ETRTO " Measuring Rim (measurement wheel rim) ".Furthermore it, it is specified that internal pressure refers to, is provided by JATMA " highest air pressure ", " the TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES as defined in TRA The maximum value of (the loading of tire limit under various cold inflation pressures) " or " INFLATION as defined in ETRTO PRESSURES (the blowing pressure) ".In addition, ordinance load refers to, as defined in JATMA " maximum loadability " is provided by TRA " TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES " maximum value or by ETRTO Defined " LOAD CAPACITY (load-bearing capacity) ".

Cross-ply 1 has corresponding bead-core 4a, 4b, 4c in each bead core 3a, 3b, 3c.Bead-core 4a, 4b, 4c are Configure the rubber material in the respective tire radial outside of a pair of bead core 3a, 3b, 3c.Section in tyre equatorial direction, The thickness of the tire width direction of bead-core 4a, 4b, 4c is positioned against tire diameter with from corresponding bead core 3a, 3b, 3c Successively decrease outward.With the rigidity of bead-core 4a, 4b, 4c is gradually decreased towards tire radial outside, can prevent as a result, In deformed set when cross-ply 1 deflects, the separation of caused CBU and cord interlayer in local deformed set can be prevented.

Cross-ply 1 has in each bead core 3a, 3b, 3c makes cord-thread direction in the cross one another multiple body piles of interlayer 10a,10b,10c.Body piles 10a, 10b, 10c by cord-thread direction it is adjacent between it is cross one another in a manner of it is wide from tire It is rolled towards outside the inside in degree direction.Body piles 10a, 10b, 10c are respectively erected between a pair of bead core.At the same time, Body piles 10a, 10b, 10c are packed in bead core 3a, 3b, 3c and bead-core 4a, 4b, 4c corresponding with them, and end is rolled up Return and it is locking.

In addition, the section in tyre equatorial direction, the height of tire radial direction is highest in multiple bead-core 4a, 4b, 4c 0.17 times or more and 0.23 times below range of the height of bead-core in carcass section height CH.For by the height of tire radial direction The height for spending highest bead-core is set in for the range, in the top load with multipair bead core and high torque vehicle It prevents from being particularly effective in terms of the separation of CBU and cord interlayer.

Moreover, cross-ply 1 further include covering multiple body piles 10as corresponding with multipair bead core 3a, 3b, 3c, Other body piles 100 of 10b, 10c.Body piles 100 for end is not rolled-up and the tire radial direction inner side of bead part 2 terminate So-called fold (turndown) construction.But, body piles 100 are also possible to its end and are rolled-up, by multiple body piles 10a, 10b, 10c are integrally packed in and terminate.In addition, body piles 100 are also possible to its end in the side of bead core 3c i.e. tyre width The outside in direction terminates.It should be noted that a part is omitted to body piles 10a, 10b, 10c and 100 in Fig. 1 Diagram.

The piece number of the respective included carcasses in body piles 10a, 10b, 10c, 100 is preferably 4 or more and 8 or less.In In top load and the vehicle of high torque, when the piece number of body piles 10a, 10b, 10c, 100 respective included carcasses is less than 4 When, it being not enough to support tyre bead, and when the piece number of carcass is more than 8, the workability when molding of cross-ply 1 is significantly impaired, Therefore, not preferably.

In addition, body piles 10a, 10b, 10c, 100 casing ply using coating rubber cover by steel or organic fiber material Expect multiple body cords that (for example, aramid fiber, nylon, polyester, artificial silk etc.) is formed and roll to be process.Body piles 10a, 10b, 10c, 100 casing ply the identical casing ply of multi-disc can be used, be also possible to different casing plies and mix. For example, can be different from other casing plies by the sulphidity of outermost 1 casing ply of the multi-disc casing ply of rollback.In this way, Cross-ply 1 has 2 layers or more of body piles.

Cross-ply 1 has slot 11 in fetus face 5.In Fig. 1, the slot bottom of slot 11 is represented by dashed line.The tire of fetus face 5 The both ends of width direction are formed as shoulder portion 6, and the defined position from shoulder portion 6 to tire radial direction inner side is equipped with sidewall portion 7. Sidewall portion 7 is disposed at the two sides two of the cross-ply 1 on tire width direction.Sidewall portion 7,7 have a pair of sidewalls rubber 17, 17。

Moreover, cross-ply 1 the peripheral side of the body piles 100 of fetus face 5 have as fiber-reinforced layer banding 8, 8a.In the private side of cross-ply 1, liner 9 is formed with along body piles 100.

Tread-rubber 15 is configured at body piles 100 and banding 8, the tire outer radial periphery of 8a, constitutes the fetus face of tire 5.A pair of sidewalls rubber 17,17 be respectively arranged at body piles 10a, 10b, 10c, 100 tire width direction on the outside of, constitute left and right The sidewall portion 7 of two sides.A pair of of rim cushion rubber 20,20 is respectively arranged at bead core 3a, 3b, 3c and carcass of the left and right sides Layer 10a, 10b, 10c, 100 rollback portion tire radial direction inner side, constitute the left and right sides bead part 2 and wheel rim 30 flange The contact surface of 30F.

As shown in Fig. 2, at 1.5 times of the height FH of flange 30F of position (FH × 1.5), by body piles 10a, 10b, 10c, 100 the radius of curvature of the innermost cord 10in of tire width direction be set as R1.Also, by from body piles 100 most 1/3 position, that is, H/3 of the length H along tire radial direction of the position of big height CH to the maximum width position of body piles 100 The body piles 10a, 10b at place, 10c, 100 the radius of curvature of the innermost cord 10in of tire width direction be set as R3.Curvature Radius R3 is the radius of curvature in the carcass inner surface portion of shoulder portion 6.Preferably, the radius of curvature R 1 of cross-ply 1 and song The ratio between rate radius R3 R1/R3 is in 0.5 or more and 1.0 ranges below.By that will be set than R1/R3 within the above range, filling When internal pressure and when deflecting, deformation is not concentrated in any one in the position of radius of curvature R 1 and the position of radius of curvature R 3 Side can prevent CBU and casing ply from separating.

In addition, as shown in Fig. 2, at 1.5 times of the position of cross-ply 1, flange 30F height FH, by body piles 10a, 10b, 10c, 100 the radius of curvature of the innermost cord 10in of tire width direction be set as R1.In addition, in cross-ply 1, at 1.5 times of the position of the height FH of flange 30F, by body piles 10a, 10b, 10c, 100 tire width direction it is outermost The radius of curvature of the cord 10out of side is set as R2.At this point, the ratio between radius of curvature R 1 and radius of curvature R 2 R1/R2 be 1.0 or more and 1.8 following.In general, when cross-ply 1 deflects, compared with the tensile stress of 1 side of radius of curvature R, curved outside, that is, curvature The tensile stress of the side radius R2 is strong.Therefore, by the way that radius of curvature R 1 is set as radius of curvature R 2 same above and 1.8 times or less Range, can easily make 1 lateral bend of radius of curvature R.As a result, body piles 10a, 10b, 10c, 100 tensile stress in curvature The side radius R1 and 2 side of radius of curvature R are equal.Therefore, the deformation between body piles 10a, 10b, 10c, 100 is reduced, and can prevent cord Layer separation.

Moreover, as shown in Fig. 2, by cross-ply 1, body piles 10a, 10b, 10c, 100 tire width direction it is most interior The radius of curvature of the cord 10in of side is set as R1, and tyre contour outline curvature of a curve radius is set as R4.In the height FH of flange 30F At 1.5 times of position, the ratio between radius of curvature R 1 and radius of curvature R 4 R1/R4 are 2.5 or less.In cross-ply 1, R1/ will be compared R4 is located above range, and body piles 10a, 10b, 10c, 100 can follow the deflection of tyre contour outline and deflect as a result, can prevent CBU caused by degree stretches.Moreover, being more preferably 0.5 or more than R1/R4.When than R1/R4 less than 0.5, caused deformation of buckling A possibility that concentration, is high, therefore not preferably.

The innermost body piles 10a of tire width direction cord 10in angle relative to tire it is circumferential 25 degree with Upper and 45 degree of ranges below.When angle is less than 25 degree, when cross-ply 1 deforms, each cord is by excessive drawing It stretches, therefore not preferably.In addition, the deformation of the cross-ply 1 when by stress becomes excessive, therefore when angle is more than 45 degree Not preferably.It is further preferred that the angle of cord 10in is circumferential in 30 or more and 40 ranges below relative to tire.

Fig. 3 is the sectional view for illustrating the tyre equatorial direction of the construction near the bead part 2 of cross-ply 1.In Fig. 3 In, body piles 10a, 10b, 10c, 100 the innermost cord 10in of tire width direction have its curved shape to tire The inside protrusion of width direction becomes the inflection point Q protruded as shown in the arrow Y1 in figure to the outside of tire width direction. Also, inflection point Q is located at 0.25 times or more of the height FH of flange 30F and 0.75 times of range below.

In addition, in Fig. 3, body piles 10a, 10b, 10c, 100 the outermost cord 10out of tire width direction have Its curved shape becomes as shown in the arrow Y2 in figure to the inside of tire width direction protrusion to tire width direction Outside protrusion inflection point P.Also, inflection point P is located at 0.60 times or more of the height FH of flange 30F and 1.15 times of models below It encloses.

Here, the section in the tyre equatorial direction of cross-ply 1, in the convex of the wheel rim 30 being embedded in for cross-ply 1 Any position of 0.9 times or more the and 1.6 times range below of the height FH of edge 30F, body piles 10a, 10b, 10c, 100 The curved shape of the innermost cord 10in of tire width direction is to protrude to the outside of tire width direction.In addition, in oblique The section in the tyre equatorial direction of tire 1,1.1 times or more and 1.6 times in the height FH of the flange 30F of wheel rim 30 are below Any position of range, body piles 10a, 10b, 10c, 100 the outermost cord 10out of tire width direction Curved Shape is to protrude to the outside of tire width direction.

[example of actual size]

Here, radius of curvature R 1 is, for example, 418mm before filling internal pressure.In the feelings to the application regulation internal pressure of cross-ply 1 Under condition, radius of curvature R 1 for example becomes 800mm ± 40mm.Radius of curvature R 2 is, for example, 391mm before filling internal pressure.To oblique In the case where the application regulation internal pressure of tire 1, radius of curvature R 2 becomes 748mm ± 37mm.Radius of curvature R 3 is in filling internal pressure precedent For example 418mm or more and 836mm or less.To the application regulation internal pressure of cross-ply 1, radius of curvature R 3 for example becomes 800m ± 40mm or more and 1600mm ± 80mm or less.Radius of curvature R 4 is, for example, 355mm before filling internal pressure.To oblique wheel In the case where the application regulation internal pressure of tire 1, radius of curvature R 4 for example becomes 680mm ± 34mm.It should be noted that wheel rim 30 is convex Edge height FH is, for example, 89mm.

[effect when high load capacity]

Fig. 4 is the figure for illustrating effect of the cross-ply 1 in high load capacity.In Fig. 4, in cross-ply 1, to liner 9, Sidewall portion 7 applies as shown in arrow Y11, arrow Y12 including the stress towards the component on the outside of tire width direction.This Outside, in cross-ply 1, in high load capacity, bigger stress, therefore, liner are applied as shown in arrow Y21, arrow Y22 9, sidewall portion 7 deflects, and is moved to position shown in dotted line from position shown in solid.Liner 9 ', sidewall portion 7 ' are moved to Position shown in dotted line, as a result, as shown in the arrow Y11 in figure, the innermost cord 10in of tire width direction is from reality The position of line is moved to the position of dotted line.At this point, the radius of curvature R 1 of cord 10in is, for example, 418mm, tire width direction is most The radius of curvature R 4 of the cord 10out in outside is, for example, 355mm.Cord 10in ' is moved to position shown in dotted line, compares R1/R2 For 1.0 or more and 1.8 hereinafter, CBU, casing ply separation does not occur as a result,.

On the other hand, Fig. 5 is the tyre equatorial direction for illustrating the construction near the bead part of the cross-ply of comparative example Sectional view.Fig. 6 is the figure of effect of the cross-ply of explanatory diagram 5 in high load capacity.

In Fig. 5, in the cross-ply of comparative example, the innermost cord 10in of tire width direction is leaned on than inflection point Q The position of tire radial outside is protruded as shown in the arrow Y1 in figure to the outside of tire width direction.However, tire is wide The case where inflection point P of the degree outermost cord 10out in direction is located at than Fig. 3 more leans on the position of tire radial outside.Therefore, cord 10out is in the position for leaning on tire radial direction inner side than inflection point P, to the inside of tire width direction as shown in the arrow Y3 in figure Protrusion.In any position of 1.1 times or more the and 1.6 times ranges below of the height FH of the flange 30F of wheel rim 30, tire is wide The outermost cord 10out in direction is spent also to protrude to the inside of tire width direction.Therefore, to comparative example shown in Fig. 5 For cross-ply, in high load capacity, it is possible to casing ply separation 200 can occur.

In addition, in Fig. 6, in the cross-ply of comparative example, in addition to liner 9, sidewall portion 7 as shown in arrow Y13 that Sample application includes also applying packet as shown in arrow Y14, Y15 towards other than the stress of the component on the outside of tire width direction Include the stress of the component towards tire radial outside.In addition, in Fig. 6, in the cross-ply of comparative example, in high load capacity, It is applied bigger stress as shown in arrow Y23, arrow Y24 and Y25, therefore, liner 9, sidewall portion 7 deflect, And position shown in dotted line is moved to from position shown in solid.Liner 9 ', sidewall portion 7 ' are moved to position shown in dotted line, by This, the innermost cord 10in of tire width direction is moved to the position of dotted line from the position of solid line.It is being moved to shown in dotted line Position in the state of, cord 10in ' becomes substantially straight curvature of a curve radius R1 ' (for example, R1 '=1002mm).Tyre width The radius of curvature R 4 ' (for example, R4 '=355mm) of the outermost cord in direction is the value equal with the case where Fig. 4.In the state Under, tire radial outside is tilted to tire radial outside sometimes, causes by bigger stress, bead core 3a, 3b and 3c CBU。

In contrast, in the cross-ply of present embodiment 1, as described above, in the tyre equatorial side of cross-ply 1 To section, in 0.9 times or more and the 1.6 times of models below of the height FH of the flange 30F for the wheel rim 30 being embedded in for cross-ply 1 Any position enclosed, body piles 10a, 10b, 10c, 100 the innermost cord 10in of tire width direction curved shape To be protruded to the outside of tire width direction, also, in 1.1 times or more and the 1.6 times of ranges below of the height FH of flange 30F Any position, body piles 10a, 10b, 10c, 100 the curved shape of the outermost cord 10out of tire width direction be It is protruded to the outside of tire width direction.It can inhibit the mistake of the body piles 10a of the inner surface side close to equatorial plane CL as a result, Degree stretches, and can prevent CBU.In addition, the compression direction (moving direction) of adjacent casing ply is set as identical, to can be reduced curtain The shearing deformation of cloth interlayer, prevents casing ply from separating.

[summary]

In order to prevent CBU caused by the excessive tensile of carcass and close to equatorial plane inner surface side body piles with Casing ply caused by deformation between outer surface side body piles far from equatorial plane separates, can be with as general measure Expect: increasing carcass the piece number to be able to bear excessive stretching, increase carcass interlayer rubber thickness to be able to bear interlamellar deformation. However, these measures will lead to increased costs, weight increases.In addition, the carcasses the piece number, rubber such as tyre bead base widths of wheel rim The increase of thickness is limited.Cross-ply according to the present embodiment can inhibit bead part, the excessive tensile of body piles, energy Endurance quality is improved without will increase carcass the piece number, rubber thickness.