tire

Abstract

To provide a tire capable of maintaining turning performance excellent on a snow road surface or a wet road surface even when wear of a tread part progresses.SOLUTION: A tread part of a tire includes at least one land part 4. The land part 4 includes: an outer region 41 positioned inside in a tire radial direction from a tread surface 40; an inner region 42 positioned inside in a tire radial direction; and at least one sipe 5. The sipe 5 includes: one outer sipe element 51 extending in the outer region 41 in a tire axial direction; and a plurality of inner sipe elements 52 extending in the inner region 42. The inner sipe element 52 includes a component 52A extending in the tire circumferential direction and is connected to the outer sipe element 51.SELECTED DRAWING: Figure 2

Description

Technical Field

[0004] ,

[0006] , ,

[0005] , ,

[0001] The present disclosure relates to a tire having a tread portion.

Background Art

[0002] Conventionally, a tire has been proposed in which a first inclined portion extending from the inner edge in the tire radial direction of the main portion of the sipe to the bottom of the sipe while being continuous with this inner edge and inclined to one side with respect to the center line in the depth direction of the main portion of the sipe and a second inclined portion inclined to the other side are alternately arranged in the length direction of the sipping (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Normally, as the tread portion wears, the rigidity of the land portion increases, so the edge effect of the sipping decreases, affecting the ice and snow performance and wet performance.

[0005] On the other hand, in the tire disclosed in Patent Document 1, by adopting the sipping having the above configuration, the increase in the rigidity of the land portion in the tire circumferential direction is alleviated. As a result, even when the tread portion wears, the edge effect at the edge of the block and the sipping during straight running acceleration and deceleration is maintained, and suppression of the deterioration of the ice and snow performance and wet performance is expected.

[0006] However, the siping disclosed in Patent Document 1 does not contain any components that extend in the circumferential direction of the tire (see Figures 1 and 2, etc.), and therefore cannot mitigate the increase in axial rigidity of the tire portion on land due to tread wear. Consequently, as tread wear progresses, the edge effect of the block edges during cornering decreases. Furthermore, since the edge effect of the siping itself cannot be expected, the ice and snow performance and wet performance during cornering decrease.

[0007] This disclosure was devised in light of the above-mentioned circumstances, and its primary purpose is to provide a tire that can maintain excellent cornering performance on icy, snowy, and wet road surfaces even as the tread wear progresses. [Means for solving the problem]

[0008] This disclosure relates to a tire having a tread portion, The tread portion comprises at least one land portion, The land portion includes an outer region located radially inward from the tread surface, an inner region located radially inward from the outer region, and at least one sipe. The at least one sipe includes one outer sipe element extending in the tire axial direction in the outer region and a plurality of inner sipe elements extending in the inner region. The aforementioned plurality of inner sipe elements include components that extend in the circumferential direction of the tire and are connected to the outer sipe elements. [Effects of the Invention]

[0009] In the tire of this disclosure, the sipes include one outer sipe element extending in the tire axial direction in the outer region and a plurality of inner sipe elements extending in the inner region, wherein the plurality of inner sipe elements include a component extending in the tire circumferential direction. Therefore, as wear progresses, the component of the inner sipe elements extending in the tire circumferential direction appears. This mitigates the increase in rigidity in the tire axial direction in the land portion, maintaining excellent cornering performance on icy, snowy, and wet surfaces. Furthermore, the edge effect of the inner sipe elements themselves provides excellent cornering performance on icy, snowy, and wet surfaces. [Brief explanation of the drawing]

[0010] [Figure 1] This is a cross-sectional view of the tread portion of one embodiment of the tire disclosed herein. [Figure 2] This is a cross-sectional view of the land area shown in Figure 1. [Figure 3] Figure 2 is an unfolded view of the land portion showing one form of the sipe. [Figure 4] Figure 2 is an unfolded view of the land portion showing another form of the sipe. [Figure 5] Figure 2 is an unfolded view of the land portion, showing yet another form of the sipe. [Figure 6] Figure 5 is a perspective view of the land area, showing the sipes from the outside in the radial direction of the tire. [Figure 7] Figure 5 is a perspective view of the land area, showing the sipes from the inside in the radial direction of the tire. [Figure 8] Figure 5 is a cross-sectional view of the land area including the sipes. [Modes for carrying out the invention]

[0011] One embodiment of the present invention will be described below with reference to the drawings. Figure 1 shows a cross-sectional view of the tread portion 2 of the tire 1 of this embodiment. Figure 1 is a meridian cross-sectional view including the tire rotation axis in the normal state of the tire 1. The tread portion 2 of this embodiment is suitably used, for example, as a pneumatic tire. However, it is not limited to this embodiment, and the tread portion 2 may also be used, for example, for an airless tire.

[0012] The "normal state" means that in the case of a pneumatic tire with various specifications defined, the tire is mounted on a normal rim and filled with the normal internal pressure, and moreover, it is in a no-load state. In the case of a tire without various defined specifications or a non-pneumatic tire, the "normal state" means a standard usage state corresponding to the purpose of using the tire and is a no-load state. In this specification, unless otherwise specified, the dimensions and the like of each part of the tire are values measured in the above normal state. It should be noted that each configuration described in this specification allows for normal errors included in rubber molded products.

[0013] The "normal rim" is the rim defined for each tire in a specification system including the specifications based on which the tire is designed. For example, in JATMA, it is the "standard rim", in TRA, it is the "Design Rim", and in ETRTO, it is the "Measuring Rim".

[0014] The "normal internal pressure" is the air pressure defined for each tire in a specification system including the specifications based on which the tire is designed. In JATMA, it is the "maximum air pressure", in TRA, it is the maximum value described in the table "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES", and in ETRTO, it is the "INFLATION PRESSURE".

[0015] As shown in FIG. 1, in the tread portion 2, for example, a plurality of main grooves 3 extending continuously in the tire circumferential direction and a plurality of land portions 4 divided by these are provided. The tread portion 2 may be configured by a single land portion 4 without forming the main grooves 3 in the tread portion 2.

[0016] The land portion 4 of the present embodiment is configured, for example, as a block row including a plurality of blocks in the tire circumferential direction. The blocks are divided by a plurality of transverse grooves crossing the land portion 4 in the tire axial direction. The land portion 4 of the present invention is not limited to such a mode, and may be formed, for example, in a rib shape extending continuously in the tire circumferential direction.

[0017] FIG. 2 shows a cross section of the land portion 4 cut in the tire circumferential direction DC. The land portion 4 includes an outer region 41 and an inner region 42.

[0018] The outer region 41 is a region from the tread surface 40 to the first distance (depth) D1 in the radially inner direction of the tire radius. The inner region 42 is located radially inward of the outer region 41 in the tire radius. The boundary 43 between the outer region 41 and the inner region 42 is separated from the tread surface 40 by the first distance D1 in the radially inner direction of the tire radius.

[0019] The outer region 41 constitutes the tread surface 40 from the new state to the midwear stage of the tread portion 2. The inner region 42 constitutes the tread surface 40 from the midwear stage to the endwear stage of the tread portion 2.

[0020] The land portion 4 includes at least one sipe 5. In the present disclosure, a "sipe" refers to a cut having a minute width, and the width between two sipe walls facing each other is 1.5 mm or less. The edge effect exerted by the edge where the tread surface 40 and the sipe wall intersect improves the snow and ice performance and wet performance of the tire 1 particularly. [[ID=​​​​​​​​​The outer sipe element 51 may be inclined with respect to the tire axis. In this case, the angle of the outer sipe element 51 with respect to the tire axis is preferably less than 45°. An angle of less than 45° of the outer sipe element 51 with respect to the tire axis improves acceleration and deceleration performance in the initial stages of wear. The outer sipe element 51 is not limited to a straight line, but may also extend in a curved or zigzag shape. Furthermore, the outer sipe element 51 may be inclined with respect to the tire radius.

[0024] Multiple inner sipe elements 52 are formed inward in the tire radial direction so as to branch off from the outer sipe elements 51 at the boundary 43 between the outer region 41 and the inner region 42. In other words, the multiple inner sipe elements 52 are connected to the outer sipe elements 51 at the boundary 43.

[0025] In the mid-to-late stages of wear, when the inner region 42 constitutes the tread surface 40, multiple inner sipe elements 52 appear on the tread surface 40. This mitigates the increase in rigidity of the land portion 4 from the mid-to-late stages of wear. In addition, the edge component that provides the edge effect increases, resulting in good ice and snow performance and wet performance.

[0026] The inner sipe element 52 includes a component 52A that extends in the tire circumferential direction DC. Here, "component extending in the tire circumferential direction DC" refers to a component that extends at an angle or perpendicular to the tire axial direction, i.e., a component that is not parallel to the tire axial direction.

[0027] The component 52A of the inner sipe element 52, which extends in the tire circumferential direction DC, appears on the tread surface 40 as wear progresses. This mitigates the increase in rigidity of the land portion 4 in the tire axial direction, maintaining excellent cornering performance on icy, snowy, and wet surfaces. Furthermore, the edge effect produced by component 52A of the inner sipe element 52 itself is expected to provide excellent cornering performance on icy, snowy, and wet surfaces. To obtain excellent cornering performance on icy, snowy, and wet surfaces, it is desirable that the angle of component 52A with respect to the tire axial direction be 45° or more.

[0028] It is desirable that the above-mentioned component 52A is non-parallel to the outer sipe element 51. Because component 52A is non-parallel to the outer sipe element 51, multiple inner sipe elements 52 with different shapes from the outer sipe element 51 appear as wear progresses, thereby increasing the degree of freedom of the inner sipe element 52 and providing even better turning performance on icy, snowy, and wet surfaces.

[0029] It is desirable that the above-mentioned component 52A increases toward the inner side in the tire radial direction. As component 52A increases toward the inner side in the tire radial direction, the amount of component 52A appearing on the tread surface 40 increases as wear progresses, resulting in even better cornering performance on icy and snowy roads and wet roads from the middle to the end of the wear stage.

[0030] Figure 3 is an unfolded view of the land portion 4 showing sipe 5A, which is one form of sipe 5. In this figure, the outer sipe element 51 is drawn with a solid line, and the inner sipe element 52 is drawn with a dashed line.

[0031] In the figure, sipe 5A has the form of a so-called open sipe, reaching both ends of the tire axial direction DA of the land portion 4. Sipe 5A may also have the form of a so-called semi-open sipe, reaching one end of the tire axial direction DA of the land portion 4, or it may have the form of a so-called closed sipe, having both ends of the tire axial direction DA inside the land portion 4. The same applies to sipes 5B and 5C described below.

[0032] In sipe 5A, the multiple inner sipe elements 52 include elements 54 that extend on the same plane as the outer sipe element 51 from a starting point 53 connected to the outer sipe element 51, and elements 55 that radiate outwards from the starting point 53 connected to the outer sipe element 51. With such sipe 5A, the component 52A extending in the tire circumferential direction DC of element 54 increases from the mid-to-late stages of wear, and excellent cornering performance on icy, snowy, and wet roads can be expected.

[0033] In addition, in sipe 5A, the multiple inner sipe elements 52 may be spaced apart from each other, or they may be connected via elements 54 that extend on the same plane as the outer sipe element 51.

[0034] Figure 4 is an unfolded view of the land portion 4 showing sipe 5B, another form of sipe 5. In this figure, the outer sipe element 51 is drawn with a solid line, and the inner sipe element 52 is drawn with a dashed line.

[0035] In sipe 5B, multiple inner sipe elements 52 include a closed element 56 that circulates from a starting point 53 connected to the outer sipe element 51. With such a sipe 5B, the component 52A extending in the tire circumferential direction DC of element 56 increases from the mid-to-late stages of wear, and excellent cornering performance on icy, snowy, and wet roads can be expected.

[0036] Element 56 is preferably formed in a polygonal shape (12-sided in the figure) when viewed from the radial direction of the tire. The polygon may also be a star shape including interior angles in which acute and obtuse angles are alternately arranged. With such a sipe 5B, the component 52A of element 56 extending in the tire circumferential direction DC increases further from the mid-to-late stages of wear.

[0037] In addition, in sipe 5B, the multiple inner sipe elements 52 may be spaced apart from each other, or they may be connected via elements 54 (see Figure 3) that extend on the same plane as the outer sipe element 51.

[0038] Furthermore, both sipes 5A and sipes 5B may be formed on a single land portion 4 of the tread portion 2.

[0039] Figure 5 is an unfolded view of the land portion 4 showing sipe 5C, which is yet another form of sipe 5. In this figure, the outer sipe element 51 is drawn with a solid line, and the inner sipe element 52 is drawn with a dashed line.

[0040] In sipe 5C, multiple inner sipe elements 52 include multiple bending elements 57.

[0041] Each of the multiple bending elements 57 includes a first offset element 57A, a second offset element 57B, and a joint element 57C.

[0042] The first offset element 57A is offset to one side in the tire circumferential direction DC relative to the outer sipe element 51 and extends in the tire axial direction DA.

[0043] The second offset element 57B extends in the tire axial direction DA, offset to the other side of the tire circumferential direction DC relative to the outer sipe element 51. The first offset element 57A and the second offset element 57B are offset to opposite sides of each other in the tire circumferential direction DC.

[0044] The joint element 57C connects the first offset element 57A and the second offset element 57B. The joint element 57C extends from one side to the other in the tire circumferential direction DC and constitutes the component 52A of the bending element 57 that extends in the tire circumferential direction DC.

[0045] The bending element 57, which includes a joint element 57C that is component 52A extending in the circumferential direction DC of the tire, provides excellent cornering performance on icy, snowy, and wet road surfaces from the mid-to-late stages of wear.

[0046] The multiple bending elements 57 are spaced apart from each other. This suppresses excessive reduction in the rigidity of the ground section 4, resulting in excellent handling stability on dry surfaces.

[0047] In this disclosure, it is desirable that the joint element 57C is inclined with respect to the tire circumferential direction DC. Such a joint element 57C constitutes a component 52B of the inner sipe element 52 that extends in the tire axial direction DA. This provides excellent acceleration and deceleration performance on icy, snowy, and wet road surfaces from the mid-to-late stages of wear.

[0048] In the flex elements 57 adjacent to each other in the axial direction DA of the tire, at least a portion of one first offset element 57A is positioned opposite at least a portion of the other second offset element 57B in the circumferential direction DC of the tire. This locally increases the density of the flex elements 57, resulting in excellent acceleration and deceleration performance on icy, snowy, and wet road surfaces from the mid-to-late stages of wear.

[0049] In this disclosure, it is preferable that in each of the multiple bending elements 57, the first offset element 57A is provided with a first discontinuing element 57D at the end opposite to the side to which the joint element 57C is connected. The first discontinuing element 57D extends toward the second offset element 57B of the adjacent bending element 57. The first discontinuing element 57D extends at an inclination with respect to the tire circumferential direction DC, in the opposite direction to that of the joint element 57C. Such a first discontinuing element 57D, in combination with the first offset element 57A and the joint element 57C, exhibits a key-shaped form, providing an excellent edge effect from the mid-to-late stages of wear, resulting in excellent acceleration / deceleration performance and cornering performance on icy, snowy, and wet road surfaces.

[0050] In this disclosure, it is preferable that in each of the multiple bending elements 57, the second offset element 57B is provided with a second discontinuing element 57E at the end opposite to the side to which the joint element 57C is connected. The second discontinuing element 57E extends toward the first offset element 57A of the adjacent bending element 57. The second discontinuing element 57E extends at an inclination opposite to that of the joint element 57C with respect to the tire circumferential direction DC. Such a second discontinuing element 57E, in combination with the second offset element 57B and the joint element 57C, exhibits a key-shaped form, providing an excellent edge effect from the mid-to-late stages of wear, resulting in excellent acceleration / deceleration performance and cornering performance on icy, snowy, and wet road surfaces.

[0051] It is desirable that, among the multiple bending elements 57, adjacent bending elements 57 in the tire circumferential direction DC partially overlap in the tire axial direction DA. In this disclosure, a portion of the first offset element 57A and the first interrupted element 57D, and a portion of the second offset element 57B and the second interrupted element 57E overlap in the tire axial direction DA. With such bending elements 57, the density of bending elements 57 is locally increased, and excellent acceleration and deceleration performance can be obtained on icy and snowy road surfaces and wet road surfaces from the mid to late stages of wear.

[0052] Figures 6 and 7 are perspective views of sipe 5C. In these figures, the outline of land area 4 is drawn with a dashed line, and the outline of sipe 5C is drawn with a solid line.

[0053] In sipe 5C, the first offset element 57A has an inclined element 58A that is inclined with respect to the tire radial direction DR. Similarly, the second offset element 57B has an inclined element 58B that is inclined with respect to the tire radial direction DR. Likewise, the joint element 57C, the first discontinuation element 57D, and the second discontinuation element 57E have inclined elements 58C, 58D, and 58E that are inclined with respect to the tire radial direction DR. The inclined elements 58A, 58B, 58C, 58D, and 58E are located outside the tire radial direction DR in the inner sipe element 52 and are connected to the outer sipe element 51.

[0054] The inclined elements 58A and 58B increase the offset amount of the first offset element 57A and the second offset element 57B as wear progresses, and the distance between the first offset element 57A and the second offset element 57B expands. Furthermore, the inclined elements 58C, 58D, and 58E increase the length of the joint element 57C, the first discontinuing element 57D, and the second discontinuing element 57E as wear progresses. As a result, the component 52A extending in the tire circumferential direction DC of the inner sipe element 52 increases, providing excellent cornering performance on icy, snowy, and wet surfaces from the mid-to-late stages of wear.

[0055] In sipe 5C, the first offset element 57A bends from the inclined element 58A and has a parallel element 59A parallel to the tire radial direction DR. Similarly, the second offset element 57B bends from the inclined element 58B and has a parallel element 59B parallel to the tire radial direction DR. Likewise, the joint element 57C, the first discontinuing element 57D, and the second discontinuing element 57E have parallel elements 59C, 59D, and 59E parallel to the tire radial direction DR. The parallel elements 59A, 59B, 59C, 59D, and 59E are located inside the tire radial direction DR in the inner sipe element 52 and are connected to the inclined elements 58A, 58B, 58C, 58D, and 58E.

[0056] By providing parallel elements 59A, 59B, 59C, 59D, and 59E on the inside of the inner sipe element 52 in the tire radial direction DR, the depth of the inner sipe element 52 is sufficiently ensured, while facilitating the release of the tread portion 2 from the vulcanization mold after the tire 1 is vulcanized. This suppresses damage to the blades used to form the sipes 5C formed in the vulcanized metal and to the rubber of the tread portion 2.

[0057] In sipe 5C, it is desirable that the ratio X / Y of the sum of lengths of the components 52A extending in the tire circumferential direction DC to the sum of lengths Y of the components 52B extending in the tire axial direction DA of the inner sipe element 52 is 0.3 to 0.7. Here, the lengths of the components 52B extending in the tire axial direction DA and the components 52A extending in the tire circumferential direction DC are measured at the inner ends of the inclined elements 58A, 58B, 58C, 58D, and 58E in the tire radial direction DR.

[0058] When the above ratio X / Y is 0.3 or higher, excellent cornering performance is obtained on icy, snowy, and wet road surfaces from the mid-to-late stages of wear. When the above ratio X / Y is 0.7 or lower, sufficient rigidity of the axial DA of the land portion 4 is ensured from the mid-to-late stages of wear. Therefore, the reduction in the actual contact area due to the deformation of the land portion 4 is suppressed, and excellent cornering performance is obtained on icy, snowy, wet, and dry road surfaces.

[0059] As shown in Figure 5, the angle θAD between the first offset element 57A and the first interruption element 57D is preferably between 90° and 130°.

[0060] When the angle θAD is 90° or greater, the first interruption element 57D, the first offset element 57A, and the joint element 57C form a key-shaped inner sipe element 52, providing excellent acceleration / deceleration performance and cornering performance on icy / snowy or wet road surfaces from the middle of wear onward. Sufficient distance is obtained between the opposing first interruption element 57D and the second interruption element 57E, ensuring sufficient rigidity of the axial direction DA of the tire of the land portion 4 from the middle to the end of wear. When the angle θAD is 130° or less, the component 52A extending in the circumferential direction DC of the tire of the first interruption element 57D easily increases.

[0061] Similarly, the angle θBE between the second offset element 57B and the second break element 57E is preferably between 90° and 130°. Also, the angle θAC between the first offset element 57A and the joint element 57C, and the angle θBC between the second offset element 57B and the joint element 57C are preferably between 90° and 130°.

[0062] Figure 8 shows a cross-section of the land portion 4, including the sipe 5C, cut along the tire circumferential direction DC. The ratio D1 / D of the depth D1 of the outer region 41 from the tread surface 40 to the total depth D of the sipe 5C is preferably 20% or less. With this configuration, the inner sipe element 52 branching from the outer region 41 appears on the tread surface 40 early, resulting in excellent cornering and acceleration / deceleration performance on icy, snowy, and wet road surfaces.

[0063] The ratio D2 / D of the depths D2 of the inclined elements 58A, 58B, 58C, 58D, and 58E from the tread surface 40 to the total depth D of the sipe 5C is preferably 95% or less. With this configuration, the spacing between the first offset element 57A and the second offset element 57B is increased in the final stages of wear. The lengths of the joint element 57C, the first discontinuing element 57D, and the second discontinuing element 57E are also increased. As a result, the component 52A extending in the tire circumferential direction DC of the inner sipe element 52 is increased, resulting in excellent cornering performance on icy, snowy, or wet roads in the final stages of wear.

[0064] The angle α of the inclined elements 58A, 58B, 58C, 58D, and 58E with respect to the tire radial direction DR is preferably 45° or less. By keeping the angle α at 45° or less, excessive spreading of the spacing between the parallel elements 59A and 59B is suppressed, making it possible to provide more sipes 5C in the tire circumferential direction DC. Note that the angle α is greater than 0°.

[0065] Although the tire 1 of this disclosure has been described in detail above, this disclosure is not limited to the specific embodiments described above and can be implemented in various modified forms.

[0066] [Note] This disclosure includes the following aspects.

[0067] [Disclosure 1] A tire having a tread portion, The tread portion comprises at least one land portion, The land portion includes an outer region located radially inward from the tread surface, an inner region located radially inward from the outer region, and at least one sipe. The at least one sipe includes one outer sipe element extending in the tire axial direction in the outer region and a plurality of inner sipe elements extending in the inner region. The aforementioned plurality of inner sipe elements include components that extend in the circumferential direction of the tire and are connected to the outer sipe elements. tire. [Disclosure 2] The tire according to claim 1, wherein the component extending in the circumferential direction of the tire is non-parallel to the outer sipe element. [Disclosure 3] The tire according to disclosure 1 or 2, wherein the component extending in the circumferential direction of the tire increases toward the radially inward direction of the tire. [Disclosure 4] The aforementioned plurality of inner sipe elements include a plurality of bending elements, Each of the aforementioned multiple bending elements is, A first offset element is offset to one side in the tire circumferential direction from the outer sipe element and extends in the tire axial direction, A second offset element is offset to the other side in the tire circumferential direction from the outer sipe element and extends in the tire axial direction, A tire according to any one of disclosures 1 to 3, comprising a joint element connecting at least one of the first offset elements and at least one of the second offset elements. [Disclosure 5] The tire according to disclosure 4, wherein the joint element is inclined with respect to the circumferential direction of the tire. [Disclosure 6] In each of the aforementioned multiple bending elements, The tire according to disclosure 5, wherein the first offset element comprises a first discontinuing element at the end opposite to the side to which the joint element is connected, extending toward the second offset element and inclined in the opposite direction to the joint element with respect to the tire circumferential direction. [Disclosure 7] In each of the aforementioned multiple bending elements, The tire according to disclosure 6, wherein the second offset element comprises a second discontinuing element at the end opposite to the side to which the joint element is connected, inclined toward the first offset element and in the opposite direction to the joint element with respect to the tire circumferential direction. [Disclosure 8] The tire according to disclosure 7, wherein among the plurality of bending elements, adjacent bending elements in the tire circumferential direction partially overlap in the tire axial direction. [Disclosure 9] The tire according to any one of disclosures 4 to 8, wherein the first offset element and the second offset element have inclined elements that are inclined with respect to the radial direction of the tire. [Disclosure 10] The tire according to disclosure 9, wherein the first offset element and the second offset element are bent from the inclined element and have parallel elements parallel to the tire radial direction. [Disclosure 11] The tire according to disclosure 9 or 10, wherein at the inner end of the inclined element in the tire radial direction, the inner sipe element has a ratio X / Y of 0.3 to 0.7 between the sum of lengths of the components extending in the tire circumferential direction and the sum of lengths of the components extending in the tire axial direction (Y). [Disclosure 12] The tire according to any one of disclosures 1 to 3, wherein the plurality of inner sipe elements include elements that radiate outward from a starting point connected to the outer sipe elements. [Disclosure 13] The tire according to any one of disclosures 1 to 3, wherein the plurality of inner sipe elements include closed elements that circulate from a starting point connected to the outer sipe elements. [Disclosure 14] The tire according to disclosure 1, 12, or 13, wherein the plurality of inner sipe elements include a plurality of elements spaced apart from each other. [Explanation of symbols]

[0068] 1: Tires 2: Tread section 4: Rikubu 5: Sipes 5A: Sipe 5B: Sipes 5C: Sipes 40: Tread 41 :Outer area 42: Inner area 51: External sipe element 52: Internal sipe element 52A: Ingredients 52B: Ingredients 53: Starting point 54: Element 55: Element 56: Element 57: Bending element 57A: First offset element 57B: Second offset element 57C: Joint element 57D: First interruption element 57E: Second interruption element 58A: Inclined element 58B: Inclined element 58C: Inclined element 58D: Inclined element 58E: Inclined element 59A: Parallel elements 59B: Parallel elements 59C: Parallel elements 59D: Parallel elements

Claims

1. A tire having a tread portion, The tread portion comprises at least one land portion, The land portion includes an outer region located radially inward from the tread surface, an inner region located radially inward from the outer region, and at least one sipe. The at least one sipe includes one outer sipe element extending in the tire axial direction in the outer region and a plurality of inner sipe elements extending in the inner region. The aforementioned plurality of inner sipe elements include components that extend in the circumferential direction of the tire and are connected to the outer sipe elements. The aforementioned plurality of inner sipe elements include a plurality of bending elements, Each of the aforementioned multiple bending elements is, A first offset element is offset to one side in the tire circumferential direction from the outer sipe element and extends in the tire axial direction, A second offset element is offset to the other side in the tire circumferential direction from the outer sipe element and extends in the tire axial direction, The system includes a joint element connecting at least one of the first offset elements and at least one of the second offset elements, The aforementioned joint element is inclined with respect to the circumferential direction of the tire. In each of the aforementioned multiple bending elements, The first offset element includes a first discontinuing element at the end opposite to the side to which the joint element is connected, which extends toward the second offset element and is inclined in the opposite direction to the joint element with respect to the tire circumferential direction. tire.

2. The tire according to claim 1, wherein the component extending in the circumferential direction of the tire is non-parallel to the outer sipe element.

3. The tire according to claim 1 or 2, wherein the component extending in the circumferential direction of the tire increases toward the radially inward direction of the tire.

4. In each of the plurality of bending elements, The tire according to any one of claims 1 to 3, wherein the second offset element includes a second discontinuous element at the end opposite to the side to which the joint element is connected, which extends toward the first offset element and is inclined in the opposite direction to the joint element with respect to the tire circumferential direction.

5. The tire according to claim 4, wherein adjacent bending elements in the tire circumferential direction partially overlap in the tire axial direction.

6. The tire according to any one of claims 1 to 5, wherein the first offset element and the second offset element each have an inclined element that is inclined with respect to the radial direction of the tire.

7. The tire according to claim 6, wherein the first offset element and the second offset element are bent from the inclined element and have parallel elements parallel to the tire radial direction.

8. The tire according to claim 6 or 7, wherein at the inner end of the inclined element in the radial direction of the tire, the ratio X / Y of the sum of the lengths of the components extending in the circumferential direction of the tire to the sum of the lengths of the components extending in the axial direction of the tire (X) is 0.3 to 0.

7.

9. The tire according to any one of claims 1 to 8, wherein the plurality of inner sipe elements include a plurality of elements spaced apart from each other.

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